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A wind tunnel experiment is designed with the objective to obtain well-behaved limit cycle oscillations for a wing section with two degrees of freedom, translation and rotation, in two-dimensional flow. This is accomplished using a setup of linear springs so that the resulting moment is a nonlinear function of the rotation angle. The experimental setup is designed so that the amplitudes of the limit cycle oscillations are sufficiently low to motivate the use of linear aerodynamics in the analysis. The experimental results are compared to analyses for two different configurations, and the agreement is fairly good.
Active nozzle control is used to improve the stability of a beam subject to forces induced by fluid flow through attached pipes. The control system has a significant effect on the structural stability, making both flutter and divergence type of instabilities possible. The stability analysis is carried out using a state-variable approach based on a finite element formulation of the structural dynamics. The simultaneous design of the control system and the beam shape minimizing structural mass is performed using numerical optimization. The inclusion of the control system in the optimization gives a considerable reduction of the structural mass but results in an optimal design which is very sensitive to imperfections. Using a simple model of the control system uncertainties, a more robust design is obtained by solving a modified optimization problem. Throughout the study, the theoretical findings are verified by experiments.
A demonstration of integrated design optimization of an aeroservoelastic system was presented. It was shown that the simultaneous design of structural and control system required a two-step procedure to result in a minimum weight design and a control law that is well-designed for all operating conditions. The essential dynamics was predicted using a aeroservoelastic model, and final design with 42% less weight penalty was obtained using the integrated approach.
Various problems on the optimal design of elastic structures subject to nonconservative fluid-dynamic forces are considered. The optimal design problem istypically posed as minimizing structural weight subject to constraints on structural stability. Traditionally, structural dimensions and orientations of fibercomposite materials are common design variables. It is demonstrated that the structural weight can be reduced further by including the design of a stabilizingcontrol system in the structural design optimization, giving an integrated optimization problem where both structural and control system parameters are used as design variables. The integrated approach may result in a design with significantly improved performance compared to traditional methods, both in terms of reduced structural weight and control system performance. Using optimization for design of mechanical systems with nonconservative external load tends to increase the likelihood of obtaining a design which is very sensitive to imperfections. As a result, the predicted performance of the optimal design may not be achieved in practice. The importance of this fundamental difficulty is emphasized throughout the thesis by comparing numerically obtained results to experiments.
The first part of the thesis is concerned with the stability and optimal design of a beam subject to forces induced by fluid flow through attached pipes. A nozzle control system deflecting the fluid jet at the beam tip is used to improve the stability of the system. The simultaneous design of the control system and the beam shape minimizing structural mass is performed using numerical optimization. The inclusion of the control system in the optimization gives a considerable reduction of the beam weight but results in an optimal design which is very sensitive to imperfections. An optimal design with improved robustness is obtained by solving a modified optimization problem. The stability of a flexible wing structure with a controllable trailing edge flap is investigated. Due to uncertainties in the numerical stability analysis, the wing is predicted to become unstable at a significantly higher speed than what is observed in wind tunnel tests. Two different approaches to stabilize the wing in flutter is demonstrated. First, numerical optimization is used to design a controller which at each flow speed maximizes the damping of the flutter mode observed in the wind tunnel experiment. Second, an integrated approach is adopted, where a simultaneous mass balancing and control law design is performed. It is argued that a two-step procedure may be required to obtain a design with minimum weight and a control law that is well-defined for all operating conditions.
The stability and optimal design of a beam subject to forces induced by fluid flow through attached pipes is investigated. The structure is assumed to have the same dynamics as a fluid-conveying pipe, and the dynamic stability is analysed using a finite element formulation of the linear equation of motion. The optimal design problem of minimizing the structural mass at fixed critical flow speed is solved. The numerical results are compared to experiments with satisfactory agreement, provided that the lower bounds of the beam dimensions are properly chosen. The influence of structural damping on the critical flow speed is significant, and is found to be strongly design-dependent.
The aeroservoelastic behaviour of a thin rectangular wing with a controllable trailing edge flap is investigated. A rather high aspect ratio motivates a numerical model based on linear beam theory for the structural dynamics and strip theory for the unsteady aerodynamic loads. Experimental flutter testing shows good agreement with the numerical stability analysis, and the impact of the trailing edge flap on the dynamics is verified by open-loop testing. The problem of stabilizing the wing utilizing the trailing edge flap is posed, and the design of a fixed-structure feedback controller is performed using numerical optimization. The problem of maximizing closed-loop modal damping with constraints on actuator performance is solved for a sequence of flow speeds and the obtained controller is synthesized using gain scheduling. The fairly large predicted increase in critical speed is experimentally verified with satisfactory accuracy.
Injuries to the neck, or cervical region, are very importantsince there is a potential risk of damage to the spinal cord.Any neck injury can have devastating if not life threateningconsequences. High-speed transportation as well as leisure-timeadventures have increased the number of serious neck injuriesand made us increasingly aware of its consequences.Surveillance systems and epidemiological studies are importantprerequisites in defining the scope of the problem. Thedevelopment of mechanical and clinical tools is important forprimary prevention of neck injuries.
Thus, the main objectives of the present doctoral thesisare:- To illustrate the dimension of cervical injuries inSweden,- To develop a Finite Element (FE) model of the uppercervical spine, and- To study spinal stability for cervical injuries.
The incidence studies were undertaken with data from theinjury surveillance program at the Swedish National Board ofHealth and Welfare. All in-patient data from Swedish hospitals,ranging over thirteen years from 1987 to 1999, were analyzed.During this period 14,310 nonfatal and 782 fatal cervicalinjuries occurred. The lower cervical spine is the mostfrequent location for spinal trauma, although, this changeswith age so that the upper cervical spine is the most frequentlocation for the population over 65 years of age. The incidencefor cervical fractures for the Swedish population decreased forall age groups, except for those older than 65 years of age.The male population, in all age groups, has a higher incidencefor neck fractures than females. Transportation relatedcervical fractures have dropped since 1991, leaving fallaccidents as the sole largest cause of cervical trauma.
An anatomically detailed FE model of the human uppercervical spine was developed. The model was validated to ensurerealistic motions of the joints, with significant correlationfor flexion, extension, lateral bending, axial rotation, andtension. It was shown that an FE-model could simulate thecomplex anatomy and mechanism of the upper cervical spine withgood correlation to experimental data. Three studies wereconducted with the FE model. Firstly, the model of the uppercervical spine was combined with an FE model of the lowercervical spine and a head model. The complete model was used toinvestigate a new car roof structure. Secondly, the FE modelwas used for a parameter study of the ligament materialcharacteristics. The kinematics of the upper cervical spine iscontrolled by the ligamentous structures. The ligaments have tomaintain spinal stability while enabling for large rotations ofthe joints. Thirdly, the FE-model was used to study spinalinjuries and their effect on cervical spinal stability inflexion, extension, and lateral bending. To do this, the intactupper cervical spine FE model was modified to implementruptures of the various spinal ligaments. Transection of theposterior atlantooccipital membrane, the ligametum flavum andthe capsular ligament had the most impact on flexion, while theanterior longitudinal ligament and the apical ligamentinfluenced extension.
It is concluded that neck injuries in Sweden is a problemthat needs to be address with new preventive strategies. It isespecially important that results from the research on fallaccidents among the elderly are implemented in preventiveprograms. Secondly, it is concluded that an FE model of thecervical region is a powerful tool for development andevaluation of preventive systems. Such models will be importantin defining preventive strategies for the future. Lastly, it isconcluded that the FE model of the cervical spine can increasethe biomechanical understanding of the spine and contribute inanalyses of spinal stability.
The focus throughout this thesis is on the fatigue characteristics of core materials used insandwich structures. Three sandwich configurations are investigated, two with cellular foamsand one with honeycomb core material These corresponds to typical materials and dimensionsused in the marine and aeronautical industry.A modified four-point bending rig, which enables reversed loading, is successfully used forconstant amplitude fatigue tests of all material configurations. The core materials are tested asused in composite sandwich beams and through the design of the specimens the desiredfailure is in shear of the core. Analyses and inspections during and after the tests supports thetheory that the fracture initiation and fatigue failure occurs in a large zone of the core withwell distributed micro cracks rather than a single propagating crack. The fatigue test resultsare plotted in stress life diagrams including a Weibull type function which provides a goodaccuracy curve fit to the results. The fatigue life of the core materials is found to be reducedwith a increased load ratio, R.The influence on the strength and fatigue performance on sandwich beams with two types ofcore damages, an interfacial disbond and a flawed butt-joint, are experimentally investigated.The fatigue failure initiates at the stress intensity locations which are present due to the predamage.The specimens with flawed butt-joints display a fatigue crack propagation in theinterface between the core and face of the sandwich while the crack propagates through thethickness of the beams where an initial interface flaw is present. A fatigue failure predictionmodel is suggested which utilises the fatigue performance of undamaged beams and thestrength reduction due to the damages. The approach is correlated with results from fatiguetesting and satisfactory correlation is found.A uni-axial fatigue tests method is developed which simplifies the rig and specimenscompared to the four point bend method. A comparison between the results from uni-axialtension/compression fatigue tests and shear fatigue tests shows good correlation, although theR-dependency differs in some cases.The fatigue crack propagation rates are investigated for two configurations: crackspropagating in pure foam core material and cracks propagating in the core material near andalong a sandwich face/core interface. The rate at which a crack propagates stable in the socalled Paris' regime is extracted for both Mode I and Mode II loading. The agreement betweenthe Mode I crack propagation rate in the pure foam and in the core/face sandwich interfacelayer supports the theory that the crack actually propagates in the sandwich core beneath astiffened resin rich layer present in the face/core interface. The stress intensity thresholds andthe limits at which the crack growth becomes unstable are further established.Acoustic Emission (AE) is used to monitor crack initiation and growth in the core, duringboth static and fatigue loading. It is found that the approximate location of AE-hits can bedetermined which demonstrates that AE has a potential both as an non destructive testing tooland to study the failure process of non-visible sub-surface damages in sandwich structures.
This paper deals with the problem of face/core interfacial disbonds in sandwich panels that are pressurised, i.e. the disbond has an initial fluid pressure that causes the disbond to deform. The problem is often referred to as a blister. The panel with a blister is then subjected to an in-plane compressive load. Four different panels are analysed and tested, having different size disbonds and different initial internal pressure. The cases are analysed using a finite element approach where the blister is modelled using fluid elements enabling the pressure inside the blister to vary as the in-plane load is applied. The analysis uses non-linear kinematics, and in each load step, the energy release rate is calculated along the disbond crack front. This model is used for failure load predictions. The four cases are then tested experimentally by filling a pre-manufactured disbond cavity with a prescribed volume of air. This air volume is then entrapped, and the panel is subjected to an in-plane compressive load. The load and blister pressures are measured throughout the test and compared with the finite element analysis. Surface strains and blister deformations are also measured using digital correlation measurements. The predicted failure loads compare well with the experimental results, and so does the blister pressures, the latter at least qualitatively.
The transition from stable periodic nonimpacting motion to impacting motion, due to variations of parameters, is observable in a wide range of vibro-impact systems. Recent theoretical studies suggest a possible scenario for this type of transition. A key element in the proposed scenario is fulfilled if the oscillatory motion involved in the transition is born in a supercritical Hopf bifurcation. If the onset of impacting motion is close to the Hopf bifurcation, the impacting motion is likely to be chaotic. A numerical simulation of a system of articulated pipes conveying fluid is used to illuminate the theory. An experimental setup is presented, where a cantilevered pipe conveying fluid is unilaterally constrained. Results from experiments are found to be in good qualitative agreement with the theory.
Injuries to the head and neck system are potentially amongthe most serious injuries in humans, since they may damage thespinal cord. It is therefore important to develop safetysystems that can prevent injuries to the neuro- system, therebyreducing human suffering and costs to society. In thedevelopment of new and improved systems for injury preventionin car accidents, accurate criteria for predicting injury dueto mechanical forces in different impact loading situations areneeded to guide the development of improved safety systems.
This thesis deals with three aspects related to theprevention of injury to the head and neck. First anexperimental and numerical study investigated how to reduce theforces on the head and neck in frontal car crashes. Secondly, afinite element model of the human neck was developed. Finally,head protection in oblique motorcycle crashes wasexperimentally and numerically studied.
Specifically, the first study is focused on a headprotection system for reducing the forces to the head and neckduring frontal car accidents. An Experimental Head RestraintConcept (EHRC), a safety belt for the head, was designed to actas a complement or alternative to the conventional airbag. TheEHRC was evaluated experimentally in frontal collision for acrash severity of 11 m/s, and numerically in frontal collisionfor crash severities of 11 and 15 m/s. Experimental dataobtained from a frontal barrier test (11 m/s) showed a 67%reduction in the HIC value from 411 (without EHRC) to 136 (withEHRC). The EHRC clearly has a potential role in the search forprimary prevention of neurotrauma injuries in frontal carcrashes. However, it should only be seen as an experimentaltool, although it clearly has a potential market for transportof disabled people.
The EHRC changed the characteristics of the response of theneck. The bending moment in the neck was shown to increase by afew percent when the EHRC was used. With available neck injurycriteria, it was not possible to determine whether this changein response is significantly negative. Therefore, there is astrong need for more advanced injury criteria for the neck inorder to optimize such a safety system.
To improve the knowledge of injury mechanisms and injurycriteria of the neck, a research was initiated to develop adetailed finite element model of the cervical spine. The modelis aimed to predict injuries in the neck for different types ofload modes and to work as a tool to create global injurycriteria from local tissue-based failure criteria.
The finite element model of the cervical spine excludingmuscles has been validated in compression-flexion where a goodcorrelation was found with experimental data. By the model itwas possible to predict experimentally found injuries as theHangman's fracture and the model was used to investigate a newcar roof structure.
In the last study a new helmet design was presented with animproved protection against tangential impacts. In this worktwo new oblique helmet testing methods were used to investigatethe behavior of the helmet. This study showed thatit ispossible to reduce the rotational energy by up to 50% by addinga low friction layer between the shell and the liner.
This thesis is concerned with stress analysis and strengthprediction in composite laminates containing bolt holes andopen holes. It covers both two- and three-dimensional analyses,and experiments have been carried out to determine criteriaparameters and to validate the analysis methods.The objective of the work on two-dimensional analysismethods has been to develop accurate and cost-efficient stressanalysis and failure prediction methods valid for complexloading conditions. Both the finite element method and a methodbased on Lekhnitskiis complex stress functions have beenused to determine the stress distribution around the hole. Inthe case of bolted laminates, the frictionless contact betweenthe bolt and the hole has been taken into account. Differentfailure criteria, including the Point Stress Criterion (PSC)and the Damage Zone Criterion (DZC) have been used to predictthe strength of test specimens subjected to complex loadingconditions. In the case of bolted laminates, simple failurecriteria for preliminary design are proposed. The validity ofthese criteria is demonstrated on multi-fastener tension- andshear-loaded test specimens. A comprehensive test programme wascarried out to establish criteria parameters and to generatedata to validate the stress analysis and strength predictionunder complex loading conditions. A special test fixture wasdesigned for this purpose. Good agreement was found betweenpredicted and measured results.The objective of the work on three-dimensional methodshas been to develop tools for three- dimensional stress andfailure analyses and to study the effect of various factors onthe strength of single-lap joints. An experimental programmewas conducted to characterize the failure mechanisms and tomeasure deformation, strain, and bending effects. Athree-dimensional finite element model of a bolted single-lapjoint has been developed to determine the non-uniform stressdistribution through the thickness of the laminate in thevicinity of the hole. The model was validated against measuredstrains and displacements from the experimental programme. Theagreement between predicted and experimental results wasgenerally good. In the failure characterisation part of theexperimental programme, it was found that the failure of thejoints was dominated by kinking. A failure analysis procedurefor the prediction of bearing failure dominated by kinking hasbeen developed. In this procedure, failure is predicted using aquadratic failure criterion evaluating fibre stress andtransverse shear stress at a characteristic distance from theedge of the bolt hole. Experimental results were used tovalidate the analysis procedure and good agreement was foundbetween predicted and experimental failure loads. The analysisprocedure were then used study the effect of eight differentparameters which affect the strength of bolted compositelaminates. The parameters studied were: laminate thickness,lay-up, bolt diameter, bolt configuration (countersunk orprotruding head), friction, clamping force, clearance andlateral support. The parametric study was organised as areduced two-level factorial test. The results from theparametric study show that laminate thickness, friction,clamping force and bolt configuration are the parameters whichhave the strongest influence on the strength of the joints.
Key words:Composite, laminate, bolted joints, openholes, static strength, failure characterization, damage,complex loading, stress analysis, three-dimensional analysis,contact analysis, failure prediction, factorial test
The research work presented here focuses on the subject oftransport aircraft design at the pre-design or conceptuallevel. The primary topics addressed are: (1) generation of avast array of new quasi-analytical expressions to permit aconceptual treatment of commercial and business transportaircraft with adequate sensitivity for more advanced tradestudies; (2) review and adoption of a method to predictstability and control characteristics (using the Mitchellmethod); (3) a study of the relative merits between variousmethods in facilitating an expedient and robust constrainedmulti-objective optimisation result within the context oftraditional conceptual design problems (Genetic Algorithms andNelder-Mead Simplex search); (4) creation of a software packageas a new and unique conceptual tool that permits the generationof design proposals in an accurate yet expeditious manner; and,(5) practical demonstration of the new conceptual designsoftware package by undertaking some actual aircraft designproposals.
The design problem is addressed using mostly closed formsolutions but transcendental expressions with much simplifiednumerical scheme algorithms have also been adopted for sake ofaccuracy. Various new models have been proposed for atmosphericproperties, geometry, gas-turbine engine performance, low-speedand high-speed aerodynamic characteristics, minimum controlspeed limited balanced field estimation, asymmetric flight,and, en route performance characteristics including definitionof operationally permissible speed schedules and flighttechniques for payload-range/fixed sector profiles optimised interms of maximum specific air range, minimum fuel, minimumtime, minimum direct operating cost and maximum profit/returnon investment. The work was extended further to include issuesrelating to the impact of vehicular attributes to pricing themarket is willing toabsorb. Useful information regarding howthese individual computational elements of the methodology maybe integrated for the purpose of constructing coherent modularsub-spaces and formulation of a basic inter-disciplinarycoupling is also presented. The mathematical foundationsderived in this work have lead to an array of tangibleconclusions that aid the conceptual designer via implicitguidelines to achieve truly balanced design concepts.
In an explicit demonstration of methodology effectivenessand relative simplicity, a software package called QCARD orQuick Conceptual Aircraft Research and Development was createdin the MATLAB environment. The new software system wasdeveloped to assist the designer in predicting, visualising andoptimising conceptual aircraft designs in a much moreinteractive and far-reaching manner than what is afforded withcontemporary applications whilst emphasising speed and economyof effort.
The methodology and software was employed for a 19 passengerturbofan commuter transport design using the cost effectiveWilliams International FJ44-2 engines. To complement this, afuselage stretch version of the baseline vehicle designed toaccommodate 31-34 passengers was also undertaken utilising agrowth version of the original FJ44 power plant. The minimumgoal for both of these concepts was to afford unparalleledcomfort through speed and spaciousness with a competitive edgeagainst turboprops in terms of economics and field performance.The final design effort involved proposal of a Trans-Atlantichigh-performance executive transport employing anunconventional Twin Oblique Lifting Surfaces, or, TOLSconfiguration. The intent here was to produce a new super-largebusiness jet able to operate up to low supersonic speeds withfield performance, en route fuel burn efficiency and costcomparable to that of contemporary business aircraft for thismarket segment.
Keywords: aircraft, conceptual, design, specifications,atmosphere, geometry, weight, aerodyanmics, propulsion,operational performance, stability and control, constrainedmulti-objective optimisation, computer aided design, regional,business, high-transonic, low-supersonic.
The purpose of the present study was to evaluate the variability in the annual head injury incidence rate in Sweden from 1987 to 2000. It was hypothesized that the annual incidence rate would decrease over time due to a variety of primary preventive strategies that have been introduced in Swedish society. We used the Hospital Discharge Register at the National Board for Health and Welfare and head injury codes 800-804, and 850-854 from ICD9 system and S2.0-S2.9, and S6.0-S6.9 codes from ICD-10 system. We evaluated the patterns of age, gender, external cause of injury (E-code), type of injury, length of hospital stay, and trends over time. Head injuries due to transportation collision were reduced over the 14-year period analysis. Falls persisted as the dominant cause of head injury. Overall, men had 2.1 times the incidence of head injury compared to women. There was a decline in younger ages experiencing a head injury over this interval, while the number of head injuries among elderly people increased over time. Concussion was about three times more frequent than fractures. Hematoma and diffuse or focal contusions had a much lower incidence rate than concussion. Concussions and fractures decreased over time. Diffuse or focal injuries showed a steady rate of occurrence over the study interval while hematoma increased. Although length of hospital stay varied widely from zero to more than 50 days, 73.6% of hospital days were confined to two days or less. The incidence rate is stable over this time frame. While head injuries attributable to transportation accidents decreased, falls made up an increasing proportion of head injuries. Since we observed an increase in head injuries among elderly, primary prevention strategies may need to be targeted at this age group, and at preventing falls.
This thesis treats various aspects of structural polymercomposites in aircraft applications. The mechanical performanceand quality of resin transfer molded (RTM) carbon fiberreinforced epoxy composites is studied. In a first part, the influence of manufacturing process parameters on the mechanicalbehavior of laminates is experimentally investigated. A number of process parameters are used as variables and performance ismeasured in terms of tensile and compressive strength as wellas interlaminar fracture toughness. The process parameters are concluded to have little affect on the measured properties. In a second part, the quality and structural performance of an entirely co-cured RTM manufactured aircraft control surfacedemonstrator is investigated. A series of quasi staticstructural tests using distributed loading is performed. Experimental results are compared with finite element analysis. Effects of impact damage on the performance are also studied.Good agreement is obtained between the predictions and the experiments.
A nondestructive method for determination of elasticmaterial properties of orthotropic plates using naturalfrequencies is developed and verified. Finite elementcalculations of the natural frequencies of the plate are matched to experimentally determined frequencies using theelastic constants as variables. The method is successfully verified even for nontrivial specimen geometries with cornersingularities. Emphasis is on practical utilization ofknowledge about numerical and modeling errors as well asexperimental uncertainties.
The optimal design of a thin orthotropic wing subject toaeroelastic constraints is studied using numerical methods andverified in low speed wind tunnel testing. The flutter speed ofthe wing is maximized using the laminate orientation asvariable. Further, the problem of increasing the flutter speed to a prescribed value using minimal amount of additional concentrated masses on a fixed wing design is investigated. The main objective of the study is to verify that the performance of the optimized design can be achieved also in experiments. It is found that the optimal design is very sensitive to uncertainties in material and structural properties.Consequently, this has to be accounted for in the problemformulation. It is shown, and experimentally verified, that the robustness requirements on the optimal design can be met byreformulating the optimization problem.
This thesis concerns various aspects of the durability offibre optic sensors embedded in composite. Since repair orreplacement of embedded sensors is not generally possible, thefunctional reliability of embedded sensors is one of the mostimportant prerequisites for successful use. The main researchobjective was to investigate the interaction between the sensorand the composite, and how this is affecting the mechanical andoptical sensor response. Fibre optic sensors embedded incomposite structures induce local stress concentrations whenthe composite is subjected to mechanical loads andenvironmental changes such as temperature and moisture. Acomplex transfer of stresses through the interfaces between theembedded sensor and the composite occurs and can result inlarge local stresses in the composite and a significant changein the response of the embedded sensor. These stressconcentrations make the interfaces susceptible todebonding.
The sensor performance was studied experimentally andnumerically. Some basic results were generated for the EFPI andBragg grating sensors. The phase-strain response was determinedduring static and fatigue loading. The results showed that thesensors were more reliable in compression than in tensilestatic and fatigue loading. Generally, the sensor reliabilityduring loading was significantly improved for the Bragg gratingsensors over that of the EFPI sensor, as an effect of thesensor geometry. This was also demonstrated in theinvestigations on impacts. Impacts do not necessarily result indamage in the composite, but might cause debonding or otherfailure modes in the sensor area. Large, local stressconcentrations occur at several positions in the EFPI sensor,which pointed out that this sensor type was not suitable forembedded applications.
The shift in focus from the sensor concept based on the EFPIsensor to that based on the Bragg grating sensor manifesteditself in several studies. The calculated deformation fieldaround an embedded optical fibre was verified in experimentsusing a high-resolution moiré interferometric technique.Furthermore, the improvement in the coating technology wasverified. A significant higher interfacial strength wasobtained with the silane-treated glass surface. The resultsindicated that at least a twofold improvement of the shearstrength was obtained.
To simultaneously measure the in-plane strain components andthe temperature change, embedded Bragg grating sensors werearranged in a rosette configuration. The relationship betweenthe optical response from each sensor and the strains in thelaminate was numerically and analytically established.
Damage lead to stress redistribution in the sensor region,which may influence the output from the embedded Bragg gratingsensor. The effect was numerically evaluated for interfacialdamage, and was compared to that of a sensor with undamagedinterface. The results showed that debonding might have asignificant influence, in particular for combined thermal andmechanical loading.
Keywords: composites, fibre optic sensor, embedded, EFPIsensor, Bragg grating sensor, durability, fatigue, impact,strain measurement, interface, stress analysis
The effect of hole drilling technique on tensile properties of COFIT plain weave composite using circular hole was investigated. As expected, the tensile properties of COFIT woven system decrease with increasing hole sizes. The laminate, which was drilled by orbital technique, seems to impart higher tensile properties and better damage resistance compared to those of conventional drilling technique. In order to predict the laminate strength with the presence of open hole, the Point Stress Criterion was used. Results indicate that good agreement was obtained between experimental and estimation tensile strengths.
The effects of underwater explosions on ships have beenstudied ever since it was realised that explosions under watercould be accomplished. In order to study the response of asandwich structure in water, exposed to an underwaterexplosion, we need to have knowledge about the whole chain ofevents, i.e. THE EXPLOSION, THE FLUID-STRUCTURE INTERACTION andTHE RESPONSE OF SANDWICH STRUCTURES.
There are several different kinds of loads generated by anunderwater explosion that might affect a vessel in water andthey are all very complex. At an explosion we have the initialshock wave that is transmitted through the water to thestructure. This initial shock wave, will give rise toadditional loads on the structure, when reflected on the watersurface and the sea bottom. The reflection on the water surfacecauses a zone of water just under the water surface to cavitateand the water surface to rise (spray dome). At the chargelocation we have the formation of the bubble, with itspulsation and migration towards the surface. At every bubbleminimum, a shock wave is generated which rapidly decreases inmagnitude for each pulsation. The bubble is also attracted tothe sea bottom and objects in the water, but rejected by thewater surface. However this is an area that is not covered inthis thesis. When the shock wave reaches a structure, thestructure moves away, but in the next instant when the pressureis applied, the structure is moving in the same direction asthe load and therefore the load pressure is decreased. As thewave hits the structure it bounces back and may causecavitation to occur at the fluid-structure interface. All thesephenomena must be taken into account when evaluating thepressure acting on a structural surface.
Finally we have the response of the sandwich structure whichdepends on the many parameters that a sandwich structure ismade up of. We have the faces with their different properties,i.e. depending on reinforcement (fibre) material, reinforcement(fibre) direction and thickness (number of fibre layers). Thecore may vary in density and thickness. This gives us a verylarge number of possible sandwich configurations. However,since we are dealing with fast loading sequences the mass andits distribution in the structure are very important.
Looking locally (transverse direction) at a sandwichstructure, the front face is first compressed into the corewhen hit by a shock wave. This initiates oscillation about thecore of the faces. This may cause significant transversetension in the faces and delamination may occur. This mode offailure has not been considered before and has to beinvestigated further in the future. Going from one dimension totwo dimensional problems leads to the study of sandwich beams.The change in behaviour of a sandwich beam when the parameterschange can in many cases be predicted by the use of a simpleexpression. In order to verify this, several numerical exampleswere analysed and some important conclusions were reached. Whenthe parameters of the sandwich beam change it is not only thestiffness of the beam that changes, but also the distributionof the energy between the faces and the core of the sandwich.This sometimes makes it very difficult to predict the completeresponse. For example, stiffer faces lead not only todecreasing deformation and face stress, but also to anincreasing core stress. This is due to the redistribution ofenergy between the faces and the core in the sandwich beam. Thebehaviour of three-dimensional structures, such as a sandwichpanel, is similar to that of a sandwich beam. One can use theexample of the beam to predict the change in the response of apanel when the parameters vary.This thesis does not try to cover the latest researchconcerning all the different phenomena occurring during anunderwater explosion. For some of the phenomena there are moreadvanced methods available. This is rather an attempt toprovide engineers with methods that can be used to solve thistype of problem.
Three dimensional (3D) fibre-reinforced composites have shown weight efficient strength and stiffness characteristics as well as promising energy absorption capabilities. In the considered class of 3D-reinforcement, vertical and horizontal weft yarns interlace warp yarns. The through-thickness reinforcements suppress delamination and allow for stable and progressive damage growth in a quasi-ductile manner. With the ultimate goal of developing a homogenised computational model to predict how the material will deform and eventually fail under loading, this work proposes candidates for failure initiation criteria. The criteria are evaluated numerically for tensile, compressive and shear tests. The extension of the LaRC05 stress based failure criteria to this class of 3D-woven composites is one possibility. This however, presents a number of challenges which are discussed. These challenges are related to the relative high stiffness in all directions, which produce excessively high shear components when projected onto potential off-axis failure planes. To circumvent these challenges, strain based criteria inspired by LaRC05 are formulated. Results show that strain based failure predictions for the simulated load cases are qualitatively more reasonable.
This thesis covers a selection of issues associated with impact response and delarknation of composite plates. The problems include contact problems, impact response and delankration testing. The interaction between Hertzian contact stresses and flexural stresses in a plate is studied by comparing a finite element solution with superposition of closed form solutions. Indentation of sandwich panels is studied experimentally and analytically by use of a novel solution which considers core crushing and large face sheet deflections. Wave controlled impact response caused by small mass impact on onhotropic plates is studied analytically and experimentally by use of a one-parameter dimensionless equation. A separate paper describes the extension of the model to sandwich plates. Analytical and experimental aspects of delamination testing are covered by an improved beam analysis of the double cantilever beam specimen and a study of analytical and experimental sources of error in the evaluation of the mixed mode bending specimen. Finally, an extensive experimental program to study the transferability of delamination growth criteria from standard coupen specimens to simple components is reviewed.
The objectives of the thesis work were to study theinteraction between embedded piezoceramic transducers andcomposite structures as well as determine techniques tosimplify the Lamb waves analysis. Firstly, this studyconsidered the design of the embedded piezoceramic transducers.Secondly, the effect of the embedded transducer on thecomposite strength as well as the influence of the mechanicallyloaded composite on the characteristics of the embeddedtransducer were investigated. Finally, to simplify the analysisof such complex Lamb wave responses, two techniques weredeveloped. They were based on the wavelet technique and amodelling technique, respectively.
The design of the embedded piezoceramic transducers wasimproved by reducing the stress concentrations in the compositeas well as in all components constituting the piezoceramictransducer, that is, the piezoceramic element, interconnectorand conductive adhesive. The numerical analysis showed that thethickness of the interconnector had no significant influence onthe stress state of the piezoceramic transducer. It was alsofound that a compliant conductive adhesive reduced the stressconcentration located at the edge of the piezoceramic element.The structural integrity of composites embedded with theimproved piezoceramic transducer was investigated. Theexperiments, performed in tensile and compressive staticloading, indicated that the strength of the composite was notsignificantly reduced by the embedded piezoceramic transducer.Further investigations were conducted to evaluate theperformance of the improved piezoceramic transducer used as aLamb wave generator embedded in composites subjected tomechanical loading. The tests were conducted in tensile andcompressive static loading as well as fatigue loading. Thestudy showed a large working range of the embedded piezoceramictransducer. A post processing technique based on the waveletswas further assessed in the detection of damage and in thedamage size evaluation. A new wavelet basis was developedspecially for processing the Lamb wave response. This method,focused on the wavelet coefficients from the decomposition Lambwave response, showed promising results in evaluating thedamage size. The wavelets offered a sensitive tool to detectsmall damage, compared to other detection methods, improvingthe damage detection capabilities. The other technique wasdevoted to the simplification of the generated Lamb waves bythe use of multi-element transducers. The transducers weredesigned using both a normal-mode expansion and a FE-method.This technique allowed reducing the effect of a Lamb wave modetowards another. This technique was successfully implemented ina damage detection system in composites.
Keywords:Embedded piezoceramic, transducer, composite,structural integrity, health monitoring, damage detection, Lambwaves, wavelets, normal-mode expansion, FE-method
The effects of hole machining defects on strength andfatigue life of carbon/epoxy laminates with open holes andpin-loaded holes subjected to static and fatigue loading havebeen investigated. Traditional drilling techniques causingvarying extent of damage and a novel method causing nodetectable damage were employed to machine the holes. Intrinsicdamage and propagation of damage during fatigue loading wasdetected using non destructive examination techniques. Theresults showed that intrinsic damage affect the strength andfatigue life considerably. They also show that during a largeportion of the fatigue life the growth of damage (mainlydelaminations ) do not affect the overall structural responseof the specimens.
Several factors affecting static strength and fatigue lifeof multiple-row bolted joints in carbon/epoxy laminates wereinvestigated experimentally and ranked in order of importance.the experiments were set up according to a design ofexperiments plan. Design factors such as the ratio between holediameter and spacing between fasteners, and type of fastenerhead proved to have significant influence on the strength andfatigue life.
The strain energy density used as a failure criterion hasbeen employed to predict delamination initiation in apin-loaded carbon/epoxy laminate. The finite element method wasused to determine the stress and strain fields in the vicinityof the pin-loaded hole. Experiments of pin-loaded specimens andsubsequent non destructive examination were used to validatethe analysis. The analytical results agree well with theexperiments.
Design variables such as hole to pin shape configuration andhole to edge distance were investigated experimentally andanalytically. Pin-loaded specimens instrumented with straingages determined the strains far and near the hole. Twodimensional analysis using the modified mapping collocationmethod was employed to determine the stresses and strains farand near the hole. The analytical predictions and experimentalmeasurements indicate that the load carrying capacity of apin-loaded hole can be altered by changing the pin-shape.
Key words:Composite, laminate, bolted-joints,pin-loaded, hole machining, damage, computerized tomography,fatigue, delamination, strength, strain energy density,boundary collocation method.
Composite sandwich structures find wide application in the aerospace sector thanks to their lightweight characteristics. However, composite structures are highly susceptible to low velocity impact damage and therefore thorough characterization of the impact response and damage process for the used material configurations is necessary. The present study investigates the effect of face-sheet thickness on the impact response and damage mechanisms, experimentally and numerically. A uni-directional, non-crimp fabric is used as reinforcement in the face-sheets, and a closed cell Rohacell 200 Hero polymer foam is used as core material. Low-velocity impact tests are performed in a novel instrumented drop-weight rig that is able to capture the true impact response. A range of impact energies are initially utilized in order to identify when low level damage (LLD), barely visible impact damage (BVID) and visible impact damage (VID) occur. A thorough fractography investigation is performed to characterize the impact damage using both destructive and non-destructive testing. The damage from the impacts in terms of dent depth, peak contact force, deflection and absorbed energy is measured. The results show bilinear responses in dent depth vs. impact energy and absorbed energy vs. impact energy. It is found than the BVID energy works well as an indication for the onset of excessive damage. Fractography reveals that there is a failure mode shift between the LLD and the VID energy levels, and that delaminations predominantly grow along the fiber direction and rotate in a spiral pattern through the thickness, following the laminate ply orientations. Finally, a progressive damage finite element model is developed to simulate both the impact response and the delamination extent, incorporating both intra- laminar and inter-laminar damage modes. The simulation shows good agreement with the experiments.


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Tonight's show is about time. We start with a look back at the beginnings of The Buzz. Then a look forward to the future: at NAB and beyond.
NAB 2016 is only a few weeks away. So tonight, we've assembled an All-Star team to predict what the hot news is going to be.

subset: commoncrawl


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More research on permanent supportive housing needed, report finds
Suzanne Wenzel has devoted years to studying homelessness – in particular, how putting a roof over someone's head can improve their entire well-being. However, a new report from the National Academies of Science, Engineering and Medicine concluded there's not been nearly enough research done on the topic.
The need for more study is urgent, said Wenzel, an author of the report and the Richard M. and Ann L. Thor Professor in Urban Social Development at the USC Suzanne Dworak-Peck School of Social Work.
She cited statistics, such as this one from the U.S. Census, that the housing-adjusted poverty rate in California (the poverty rate when factoring in housing costs) exceeds 20 percent.
"There's a lot of evidence that homelessness is horrific for people's health," Wenzel said. So if the chronically homeless are provided with housing, "how exactly is their health changing?" she said.
In October 2016, Wenzel was asked to join an 11-person expert panel convened by the National Academies to review and evaluate the research on whether permanent supportive housing (PSH) improves the health of the chronically homeless.
Despite combing the literature for answers, the committee could find very little research, outside of studies of people living with HIV/AIDS. "We were disappointed to learn that there isn't sufficient evidence out there yet," she said.
The National Academies report on permanent supportive housing, published in July, gave pointed directions for future studies. It called for collaboration on the issue between the federal departments of Health and Human Services and Housing and Urban Development; research into which health issues suffered by the chronically homeless would be most helped by PSH; studies of which supportive services are the most effective in these situations; a push for states to include housing-related services as part of their Medicaid-reimbursable benefits; and an increased effort by the federal government, working in concert with non-profits and state and local governments, to increase the supply of such housing.
Making a difference
Although peer-reviewed studies on the subject are scant, formerly homeless people can testify to the difference permanent supportive housing has made in their lives.
Magdalena De Leon fled Sacramento after losing a child custody battle, eventually landing on the streets of Los Angeles.
"You don't have a bathroom, you don't have a shower, you don't have a kitchen, you don't have a roof over your head," she said of the two years she stayed on the streets. "It's very difficult to live like that, especially on the rainy days. Lucky me, I had a tent."
Eventually, she learned of the Downtown Women's Center, an LA organization on Skid Row that serves and houses homeless and formerly homeless women, and stopped in for a meal. "The first day, I was impressed," she said. "So many tables. A clean place with a lot of lights. A front desk. I said, 'Here looks like a little palace.'"
By the next day, she had moved in; she's now been there six years. Since she began living at the center, she's gotten help learning to manage her asthma, diabetes, high blood pressure, depression and schizophrenia.
Before she came to the center, "I was almost losing all my hope," she said. Even now, "some days I still don't believe [I'm here, like it's] the first day," she said. "I keep thinking, 'This is not a dream.'"
De Leon's experience illustrates Wenzel's belief that PSH can make a profound difference in the life of society's most vulnerable. Studies, like the ones called for in the report, would show who best to target for housing, and what supports could most help them.
"We know that homelessness is really bad for people's health," Wenzel said. "So, what are the health benefits of being in housing?"
Explore further


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Pregnacare Tummy rub Oil 's unique formula is infused with a blend of organic oils, It help to reduce the appearance of stretch marks and contribute towards boosting elasticity, helping your body stretch safely. Its luxurious oil soothes itching for long-lasting comfort. It strengthened skin to improve its appearance. Pregnacare is suitable for even sensitive skin, you can experience a nourished, hydrated and silky soft tummy.
How to use - Apply twice a day throughout pregnancy from above bust to below the bum. Continue use for four months after the baby arrives.


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Tour Itinerary
Day 1: Srinagar
On arrival at srinagar, you will meet our representative at the airport and transfer to hotel. Evening lake trip, nehru park, open lake view, swimming boats, kabutar khana, shooting point mission kashmir, floating market, vegetable gardens of the lake, floating garden, meena bazar by a luxurious shikara. Overnight at hotel.
Day 2: Srinagar local sightseeing
Half day tour of world famous mughal gardens visiting the nishat bagh( the garden of pleasure) built by asif jha in 1636 and shalimar bagh (abode of love) built by jehangir for his beloved wife nur jahan in 1619. Visit shankracharya temple (shiva temple), over looking the magnificient srinagar city and lakes. Overnight at hotel.
Day 3: Srinagar- gulmarg ~srinagar
Full day tour of gulmarg which is one of the most beautiful summer resorts in the valley. Enjoy the splendor of nature and snowy mountain. One can have gondola ride (cable car) from gulmarg to khilanmarg ( at own cost ). In the evening return to srinagar, overnight at hotel.
Day 4: Srinagar
Afternoon transfer to the airport for onward destination.
Payments Terms
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Destinations Covered : Srinagar, Pahalgam, Gulmarg


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Elissa Denslow and Matthew Maloney of Louisville, Ky., are the parents of a daughter, Ava Grace, born July 10, 2007.
She weighed 8 pounds, 8 ounces.
Grandparent are Brenda Eloge of Savannah, Ga., Dan Denslow of Mansfield and Paul and Mary King of Louisville, Ky.
Great-grandparents are Virginia Johnson and the late Charles Johnson of Ashland. Charles Hensley and Maurise and Loraine King of Kentucky.
Jerry and Alicia Ables of Sullivan are the parents of a son, Tristan Scott, born July 11, 2007, at Samaritan Hospital.
He weighed 7 pounds, 14 ounces.
Grandparents are Randy and Kay Keener and Jerry and Jean Ables, all of Ashland.
Great-grandparents are Jeanette Kitchen, Virginia Weaver and Doris and Darryl Piatt, all of Ashland.
Wade and Suzanne Miller of Ashland are the parents of a son, Guardian Wade, born July 12, 2007, at MedCentral Mansfield.
He weighed 7 pounds, 9 ounces.
Grandparents are Jim and Jane Barr and Lonnie and Nancy Miller, all of Ashland.
Great grandparents are O'Rear and Kathleen Baker of Ashland.
Justin and Rebecca Calame of Ashland are the parents of a son, Spencer Lee Calame, born July 8, 2007, at Samaritan Hospital.
He weighed 7 pounds, 7 ounces.
Grandparents are Tim Brumbaugh, Tim and Luanne Calame and Renee Brumbaugh, all of Ashland.
Great-grandparents are Sue Crist and Louise Brumbaugh, both of Ashland, and Carol Salyers of Mansfield.
LaVerne E. III and Christine E. Norris of Lucas are the parents of a daughter, Olivia Elizabeth, born July 2, 2007, at Samaritan Hospital.
She weighed 7 pounds, 8 ounces.
Grandparents are Ron and Janet Foltz of Wooster, LaVerne and Kim Norris II of Ashland and Pearl Norris of Columbus.
Great-grandparents are Pearl Foltz of Wooster and LaVerne and Lucille Norris I of Ashland.
Jessica and Shaun Furlong, of Lansing, Mich., formerly of Ashland, are the parents of a son, Isaac Joshuwa Furlong, born Wednesday, July 18, 2007, at Ingham Medical Center in Lansing, Mich.
He weighed 8 pounds, 6 ounces.
Deb Mosher and Mike Brooks of Greenwich and William and Sheila Furlong of Lansing, Mich., are grandparents.


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Why Indiana Shouldn't Fall for Obamacare's Medicaid Expansion
Ever since the Supreme Court let states opt out of the new health‐care law's Medicaid expansion, supporters have been pressuring them to opt in. Before dissecting the supporters' unbelievable arguments, it's important to look at what they're asking states to expand.
Medicaid already spends $460 billion annually, ostensibly on health care for the poor. A lot of that money never reaches the poor. Shady providers, drug dealers, organized criminals, states and even middle‐class families all take a big slice. Medicaid fraud and abuse cost taxpayers maybe $100 billion annually.
Meanwhile, many enrollees can't even find a doctor. One‐third of primary care physicians won't take new Medicaid patients. Only 20 percent of dentists accept Medicaid. In 2007, 12‐year‐old Deamonte Driver died — yes, died — because his mother couldn't find one of those dentists.
Only one reliable study has tried to measure whether this 47‐year‐old program even improves health. It has so far found only questionable gains in self‐reported health and no evidence that Medicaid saves lives.
Rather than reform this unhealthy program, the health‐care law pulls millions of more patients into it. According to one estimate, more than 80 percent of adults who would enroll in the expansion currently have private coverage, where access to care is better.
Washington's 90 percent share of the cost totals $1 trillion over the next decade. According to economist Jagadeesh Gokhale, who advises Social Security on how to make such projections, the expansion would cost states such as Florida, Illinois and Texas $20 billion apiece — and that's if Washington keeps paying 90 percent. Politicians from both parties, including President Barack Obama, have proposed reneging on that commitment. To cover their share, states would have to raise taxes or cut existing services such as education, year after year.
It's not easy to sell such a rotten deal, but that hasn't stopped supporters from trying. Here are their main arguments:
• If we don't expand, other states will get our share of the money. Supporters pretend Congress has collected a fixed pot of money from all states that it will divide among states that participate in the expansion. Yet Congress hasn't collected or set aside a dime. When states choose to participate, the Treasury will borrow money to cover its share of the cost, which taxes future taxpayers, not current ones. States can therefore reduce federal deficits by not participating.
• Not expanding could hurt a state's credit rating. Perhaps, but according to Moody's, "sensitivity to federal spending reductions [and] dependence on federal transfers" also can hurt a state's credit rating.
• Not expanding will expose employers to penalties. In states where the expansion is a live issue, those penalties are illegal. If supporters care about employers, they should challenge those illegal penalties in court (as Oklahoma has).
• States can always drop out later. Even if federal law allows participating states to quit the expansion, which legal experts dispute, states almost never curtail Medicaid eligibility.
• God favors Medicaid expansion. Though Ohio Gov. John Kasich and others have made this claim, Jesus never instructed anyone to put Caesar in charge of healing the sick.
• Using expansion dollars to purchase private insurance would reduce costs. Arkansas hopes to use federal dollars to buy "private" coverage for expansion enrollees, yet estimates by the nonpartisan Congressional Budget Office suggest this option would increase costs for state and federal governments by 50 percent.
• Expanding Medicaid would create jobs. Dead wrong. Government spending eliminates jobs. Besides, as two Harvard economists write in the New England Journal of Medicine, "Treating the health care system like a (wildly inefficient) jobs program conflicts directly with the goal of ensuring that all Americans have access to care at an affordable price." The moment this health‐care program becomes a jobs program, we should eliminate it, not expand it.
The expansion would only worsen Medicaid's pre‐existing conditions, which include fraud, abuse, poor access to care, crowded emergency rooms, inefficient care, high taxes, deficit spending and dependence on government. No wonder supporters want to distract voters from how much the expansion would cost and how little it would help.


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Authorization & Financial Policy
Thank you for choosing Clyde Park Veterinary Clinic. Our primary mission is to deliver the best and most comprehensive veterinary care available for your pet. For some treatments or hospitalized care, a deposit of 50% will be required to begin treatment. We will gladly prepare a written estimate if you desire. ALL FEES ARE DUE AT TIME OF SERVICE. There is a $35 return check fee. If you have an account 90 days past due, Clyde Park Veterinary Clinic may take legal action to recover the balance of your account and additional fees. You agree to reimburse us the fees of any collection agency, which may be based on a percentage at a maximum of 30% of the debt, and all costs, and expenses, including reasonable attorneys' fees, we incur in such collection efforts. A $5 billing fee will be applied to all outstanding account balances older than 30 days. WE ACCEPT Cash, Check, Visa, MasterCard, Discover, and CareCredit.
To prevent the spread of infectious diseases and for the protection of all hospitalized patients and employees, all pets must be current on vaccines and free from internal and external parasites. If your pet is found to have fleas while here for grooming, your pet will be treated immediately with CapStar and you will be charged a small fee. The signature below authorizes this minimum level of preventative care.


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A CT scan of a McDonald's Filet O'Fish sandwich. [via Radiology Art]
Out of Good Options for Detroit. When G.M. and Chrysler asked for billions of dollars in government money last week, they argued that it would ultimately cheaper for taxpayers than if they filed for bankrutcy. But the Obama administration is looking into letting the automakers file for bankruptcy, but said that the efforts to line up a loan — which would be the largest bankruptcy loan ever — is just the administration performing "due diligence." There's no guarantee that either route will fix Detroit's serious problems and keep it from failing. But if it does fail, it would pretty much mean the economic devastation of the entire Midwest. Good times. (Related: One of the House Republicans who represents suburban Detroit defends his opposition to the stimulus.)
And a $2.50 ATM Surcharge The government mulls taking a 40% stake in Citigroup.
The Heartbeat Grows Fainter. The company that owns the Inquirer and the Daily News, my hometown papers, is going to file for bankruptcy. Sigh.
The Man Behind the Stimulus. You may have seen John Maynard Keynes ' name pop up a lot since the economy went in the toilet. The recently passed stimulus package was based on his theory that governments can spend their way out of downturns. Liberal economists like Paul Krugman point to the U.S. economy after the New Deal/WWII as proof that it worked. Conservative ones like Tyler Cowen aren't so sure. This American Life gives a typically brisk, sharp intro to Keynes (smart, weird, kind of a dickhead) and explains why his ideas still spawn so much disagreement all these decades later. (For the more advanced economists out there, you should holler at/follow Eric's blogging over at Edge of the West.)
Can I Get a …From Ryan Lizza'svery good New Yorker piece on Rahm Emmanuel: "He is a political John McEnroe, known for both his mercurial temperament and his tactical brilliance. In the same conversation, he can be wonkish and thoughtful, blunt and profane. (When Emanuel was a teen-ager, he lost half of his right middle finger, after cutting it on a meat slicer—an accident, Obama once joked, that rendered him practically mute.')"
Latest posts by G.D. (see all)
- Random Midday Hotness: Desiigner Freestyle. - June 24, 2016
- Affirmative Action Is Not Quite Dead Yet. - June 23, 2016
- Random Midday Hotness: No One Matches His Practical, Tactical Brilliance. - May 10, 2016


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Atlas Genius Talk Tour, New Single At Lollapalooza
Australian pop/rock powerhouse Atlas Genius — comprising brothers Keith and Michael Jeffery — seem at home on the road. Fresh off last night's showcase at Chicago's Subterranean and just before their set on the BMI Stage, we talked with Atlas Genius backstage at Lollapalooza about how art sometimes imitates life on the road and how their new single, "63 Days," was born out of their touring experience.
More Interviews: MØ On Writing "Nights With You"


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Art in Motion's mission is to make Lexington a more vibrant, livable city through the fusion of public art, public transit and public spaces. Our local, non-profit organization works to enhance Lexington's only public transit system—Lextran—through the design and construction of bus shelters that incorporate art murals and sculpture.
We're creating opportunities for citizens to connect with their neighborhoods through art while growing public transit in Lexington. Increased public transit ridership means less traffic congestion and fewer climate changing carbon emissions. Those environmental benefits, combined with a richer streetscape shaped by public art, means higher quality of life for our community.


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National Museum and Singapore Arts Museum are iconic museums around Bras Basah.
To capture night scenes, all you need is a tripod and "manual" setting :
- iso 100
- shutter 20 to 30s
- aperture F13 to F18
Beautiful illumination in the evenings.
Clouds rushing over National Museum's dome.
Fast flowing vehicular movement outside Majestic museum.
Chijmes, look so quiet externally.
Singapore Arts Museum, we always see people stopping to take photo at this spot.
The reflection pool above Bras Basah MRT is another popular spot to capture SAM's reflection.
More Night exposes can be found at our SengkangBabies Fanpage.
Do drop by our other night shots too :)
- Marina Bay @night
- ClarkeQuay @night
- Museum @night


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Viewpoint: Manmohan Singh has stayed on too long
India's Prime Minister Manmohan Singh is 80. Writer and historian Ramachandra Guha assesses his performance in office.
In April 1958, Jawaharlal Nehru went for a holiday in the hills to sort out his future.
After 10 bruising years as India's prime minister, he wanted a spell as a private citizen.
He thought he should give up his job, catch up with old friends and with his reading, and go on a "slow pilgrimage" to different parts of the country. In the end, Mr Nehru was persuaded to reconsider his decision, and stay on in office.
Had Mr Nehru retired in 1958 he would be remembered as not just India's best prime minister, but as one of the great statesmen of the modern world.
He had helped nurture a plural, multi-party democracy against massive opposition and in the face of widespread scepticism. He had forged innovative and independent-minded economic and foreign policies. He had made sure that India would not be a Hindu Pakistan.
After 1958, however, Mr Nehru's problems began.
Bruised reputation
The first major corruption scandal (the Mundhra affair) took place under his watch; then he acquiesced in the shocking dismissal of an elected Communist state government in Kerala.
A spate of border conflicts erupted, culminating in the humiliating defeat at the hands of the Chinese Army in 1962. When Mr Nehru died in May 1964, his reputation lay in tatters.
Manmohan Singh is no Mr Nehru; but his term in office bears some curious resonances with that of his illustrious predecessor. His well-wishers had hoped he would retire in 2009, and perhaps the thought crossed his mind itself.
After the Gujarat riots and the vulgar 'India Shining' campaign, his compatriots needed a safe, steady, understated hand; this Manmohan Singh and his government had provided.
Religious tempers had been calmed, government functioning made more transparent (through the right to information law), and a series of welfare measures for the rural poor (pre-eminently, the Mahatma Gandhi National Rural Employment Guarantee scheme) initiated. He had done his job; it was time now to make way for a younger man (or woman).
Had Manmohan Singh retired in 2009, history would have remembered him as one of the two main architects (PV Narasimha Rao being the other) of economic liberalisation in India; and as a moderately successful prime minister.
But, unable to resist the lure of office, he stayed on.
In his second term, he has presided over what is arguably the most corrupt government in Indian history.
The series of scandals - Commonwealth Games, telecoms spectrum, 'Coalgate' - that he has failed to prevent, detect or take prompt action over have massively damaged his party and his government and irretrievably dented his own reputation.
In the 1990s, in the first flush of the liberalisation he helped initiate, those entrepreneurs with the most creative ideas tended to do best; now, with him as prime minister, it is the cronies with the best contacts who flourish.
The corruption apart, the second term of the Congress-led government has also been marked by apathy and incompetence.
There have been no imaginative measures of the right to information law or the jobs for work scheme. In 2004, when Manmohan Singh, himself a trained economist, became prime minister, there were great hopes that he would modernise administration, bring well-qualified professionals into public service, and insulate civil servants and police officers from political interference.
He has done nothing of the kind; rather, he has been unwilling to disturb in any way the networks of patronage that have so grievously damaged the ability of the Indian state to provide decent education, health care and public safety to its citizens.
Political authority
Slow, timid, status quoist, and, above all, corrupt; these are the terms in which Manmohan Singh and his second government will be remembered.
It need not have turned out that way.
But then the Indian case is illustrative of a much wider phenomenon; of once competent, once admired politicians who stay on too long in office and see their reputation diminish as a result.
This may be why the United States introduced a two-term limit for their presidents.
Across the Atlantic, Margaret Thatcher and Tony Blair, seen as modernising go-getters in their early years in office, had eventually to be defenestrated by their own colleagues to save their party's reputation.
In August 2011, in an article for the Hindustan Times, I urged the prime minister to resign.
His apathy, age and lack of independent political authority were increasingly evident.
"It is time," I wrote, that Manmohan Singh "made way for a younger man or woman, for someone who has greater political courage, and who is a member of the Lok Sabha [lower house] rather than the Rajya Sabha [upper house]. As things stand, with every passing day in office his reputation declines further. So, more worryingly, does the credibility of constitutional democracy itself."
When I wrote this I knew that India was not the United Kingdom.
Unlike in the case of Mrs Thatcher or Mr Blair, the Congress party, itself timid and status quoist, was not likely to ask Manmohan Singh to leave office.
My appeal, rather, was to his own reason and background; surely, as a well read and historically minded intellectual himself, he knew it was now time to retire from politics?
The great Indian cricketer Vijay Merchant, when asked why he had retired from the game after scoring a century in his last Test innings, answered: "I wanted to go when people asked 'Why' rather than 'Why Not'?"
This is a lesson few cricketers have heeded, and even fewer politicians. In staying on so long in office - despite the cost to his party, his government, his country and himself - Manmohan Singh is in the rather elevated company of Winston Churchill, Charles de Gaulle, Margaret Thatcher and Jawaharlal Nehru.
Ramachandra Guha's books include India after Gandhi and Makers of Modern India. He lives in Bangalore. The views expressed in this article are his own.


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Despite the traditional summer slowdown, area gun retailers are seeing elevated handgun sales primarily from customers wanting to put new concealed-carry permits to use.
The heightened sales happening locally follows a national trend that has gun retailers selling more concealable, compact pistols to buyers interested in self-defense. CRT Capital, a national financial services firm, recently found that compact pistol sales are doubling the rate of overall handgun sales.
Gun manufacturer Colt is working to boost handgun production by 50 percent, while Smith & Wesson's handgun sales increased by nearly a third at the end of 2013. In Illinois, gun shops from Marengo, McHenry and East Dundee have seen the new concealed-carry law drive compact gun sales.
"Illinois has more gun rights than it did six months ago," Marengo Guns owner Dominic DeBock said. "That's reassuring people."
About 60,500 Illinois residents possess a concealed-carry license since the Illinois State Police began accepting applications Jan. 5, according to agency figures. In McHenry County, about 1,870 residents now have a concealed-carry permit, a steady increase from the 822 applicants in mid-January.
State Police spokesperson Monique Bond said the program's popularity has been trending upwards. Officials, she said, should see an additional spike in applications after the agency introduces a manual process within the coming weeks for gun owners who don't readily have access to a computer.
The loosened gun restrictions in a state that was the last in the nation to pass a concealed-carry law comes on the heels of unprecedented gun production in the United States.
During President Barack Obama's first term, the number of firearms manufactured in the country nearly doubled, going from 4.49 million in 2008 to 8.57 million in 2012, a recent report from the Bureau of Alcohol, Tobacco, Firearms and Explosives shows.
The yearly increases dramatically outpace production during George W. Bush's presidency. Firearm production increased from 3.79 million in 2000 to 4.5 million in 2008, according to the ATF.
Following the 2012 mass shooting in Newtown, Conn., gun retailers saw a major sales boost from customers who feared increased gun restrictions from Congress. The "frenzy" nearly emptied the shelves at HP Shooting Center in McHenry by the following spring, said owner Bill Preskar.
Although gun regulations languished in Congress, the McHenry store and indoor shooting range continues to see new customers interested in handguns. Preskar sees both the concealed-carry law and gun debate driving interest.
"We are seeing a lot more new customers, a lot of people who were on the fence before," he said. "When you tell people you can't have something, then all of the sudden they want it."
Marengo Guns has also benefited from Illinois' move toward concealed carry and heightened concern about gun control, although the fear has subsided since the aftermath of Sandy Hook, DeBock said.
"Guns laws themselves have become less restrictive during this time of paranoia," he said. "That's reassuring people to keep their firearms."


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Early-age thermal cracking occurs when the tensile strain, arising from either restrained thermal contraction or a temperature differential, exceeds the tensile strain capacity of the concrete. In high strength concretes autogenous shrinkage may also contribute to early contraction. Numerous factors influence the risk of early-age cracking including the temperature rise; the coefficient of thermal expansion of the concrete; the restraint to movement offered either by adjacent elements or by differential strain within an element; and the ability of the concrete to resist tensile strain. This guide provides a method for estimating the magnitude of crack-inducing strain and the risk of cracking; and where cracking will occur. Guidance is provided on the design of reinforcement to control crack widths. Significant changes since the last revision to this report in 1992 include compatibility with EN 1992-3:2006 and EN1992-1-1 with regard to the properties of concrete and the design of reinforcement.
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It may sound harsh but I see statements from some observers that after Sandy Hook massacre America accepted that even kids can be shot and no meaningful gun control can be introduced. Another day, and another shooting at high school in Parkland. Can we really say that at least part on American society simply accepts that those things happen on regular basis, is it possible to change this attitude? Read few comments.
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Filed under: Politics, Society, United States, US politics | Tagged: Crime, Gun Control, Gun violence, Mass shooting, Parkland shooting, Politics, Society, Unitid States, US politics, US society | Leave a comment »


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Exploring Inventory Struggles at Cannabis Dispensaries
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Profiles of Living
What is the Reams Biological Theory of Ionization (RBTI) and how does it apply to human digestive health and nutrition? This book will give you a complete overview of what RBTI is and how it may benefit you and your families health.
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By Grace Isaac
The Police in Osun State on Monday arraigned a 32 year old man who is also an ex convict, Shaheed Ganiyu before an Osogbo Magistrate Court in Osun State for burgling into a house and stealing the sum of N50,000.
Ganiyu was docked on four counts charge of stealing, felony and unlawful escape from police custody.
The prosecutor, Inspector Fagboyinbo Abiodun told the court that Ganiyu broke into the house of one Abosede Fayemi with the intent to commit felony on November 11 at Agunbelewo area in Osogbo.
Abiodun said the accused stole a Hp laptop, iPhone, Blackberry phone, Firstbank ATM card, jeweleries putting the value of items stolen from Abosede's residence to about N250,000.
The prosecutor also stated that the accused escaped from police custody where he was detained.
He stated further that the accused has been involved in different cases of house burglary and stealing with him granted bail on different occasions at the same Magistrarte Court.
Inspector Abiodun argued that the offense contravenes section 411(1)(2), 390(9) , 135(b) of the criminal code cap 34 volume 11.laws of Osun State 2002.
The accused pleaded not guilty to all the four counts charge.
The defense counsel Mr Okobe Najite prayed the court to grant his client bail in the most liberal and affordable terms.
He said the accused is ready to provide a reliable surety if granted bail.
The magistrate, Mrs Fatimoh Sodamade granted the accused bail in the sum of N200,000 with one surety.
She said surety must a civil servant level 12 and must provide evidence of three years tax clearance.
The case was adjourned to December 12 for hearing.


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Spotlight on the Class of 2018
Daniel Davis
Associate in Arts Degree
Liberal Arts/Psychology
Phi Theta Kappa Honor Society
Honors Program
He Left His Comfort Zone and Excelled at PCCC
When Daniel Davis first arrived at PCCC, he walked into what felt like a different world. "I was totally out of my comfort zone," he said.
A lifelong Passaic resident and the youngest of five siblings, Daniel had spent most of his life in tight-knit Jewish communities which included his high school in New York City, the Marsha Stern Talmudical Academy-Yeshiva University High School for Boys, known as MTA-YUHSB.
"Coming to PCCC was refreshing and scary. And it's the best decision I ever made," said Daniel.
"The classes are great, and I've met so many different people. It's a very diverse environment."
PCCC has been an academic stimulus for the former underachiever who, this month, will graduate with honors in the Class of 2018, receiving an Associate in Arts Degree in Liberal Arts/Psychology. He is also a member of both the Phi Theta Kappa (PTK) Honor Society and the Honors Program.
"My parents are really happy about that," said Daniel. "I was a mediocre student in high school, but "I had a brain change and matured," he said. "I was motivated by PCCC and enjoyed the energy of being around other students who were ambitious and working hard."
Daniel's journey to PCCC was indirect. Due to his undistinguished high school performance, Daniel was not accepted by Yeshiva University, the college that is affiliated with his high school. He decided, instead, to postpone college.
"I took a gap year," he said. "I went to Israel and attended a study program at a school called Aish-Gesher in Jerusalem." Daniel explained that the purpose of the program is to deepen Jewish students' understanding of their faith and culture. "You learn more about how to be Jewish," he said. "People come from all over the world to study there."
While at Aish-Gesher, Daniel had a different kind of education, living for ten months in the historic and sacred section of Jerusalem known as the Old City. "That was really awesome," he said. "It was incredible to be in that part of the world and visit places like Masada and the Temple Mount," said Daniel, referring to two of Israel's most significant ancient historical and religious sites.
When he returned home from Israel, Daniel knew it was "time for me to decide what my next step would be." He and his parents explored the options and decided that PCCC seemed like a good place to get started on a college education.
Daniel started his PCCC studies in developmental level classes in order to improve the level of his skills. "I was pleasantly surprised by the teaching and classes here," he said. "I really got better at writing papers, thanks to Professor (Diana) Blauvelt. She was amazing."
Gradually, his academic performance improved so much that Daniel was invited to join Phi Theta Kappa.
"It was a great surprise," he said.
As a member of PTK, Daniel was excited by the experience of studying and socializing with other high achieving students. "I was in a niche with people who were excited about their work. We discussed math, nutrition, science…just so many things. It was a great atmosphere."
He was also encouraged to enter the Honors Program which provides academically talented students with more challenging and enriching experiences. Enthusiastic about the recently redesigned Program, Daniel had the opportunity to compare his class experience in Western Civilization I with that of Western Civ II, which was offered in the new format featuring smaller, seminar-style classes.
"I had Professor (Martha) Brozyna for both," said Daniel. "She's exceptional, but I really enjoyed the second course better. There were only 10 of us in class, and we had more discussions, shared different perspectives in depth, and grew much closer. It was great to be with people who were so interesting and serious about their studies."
The psychology major is particularly attracted to the work of Carl Jung. "His concept of the collective unconscious fascinates me," said Daniel, who plans to pursue a bachelor's degree in psychology at Rutgers, New Brunswick.
His career plans are still wide open. "It's still early in the game," Daniel explained. "Being a psychologist sounds really great, but I'd like to wait before I make any career decisions. There's so much more I'd like to explore."


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This column is archived at: https://aardvark.co.nz/daily/2018/0712.shtml
Not that we needed any more proof... but doesn't this whole Amazon tax thing simply deliver further proof that our (and Australia's) politicians are arrogant, stupid and naive?
Hell, if someone as ill-versed in international politics and tax as myself could see the holes in it right from the get-go, surely Australaisia's best and finest minds could have also seen that this was never going to fly -- or does arrogance and power cloud one's vision to an even greater extent than I'd imagined?
It would appear that even in the 21st century (more tha two decades since we first said it) our politicians still "don't understand the internet" and how it effectively disempowers them in favour of "the people".
I can't help but remind folks that this political philistine still believes that the problem (in respect to contemporary politics) lies, not with the people but with the system. Cue plug for Recoverable Proxy


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The last in this series of guest blogs from Nexus Copywriting
Over the past 4 weeks we've looked at how to establish your new copywriting business. For the final instalment of this series I want to think about the future, ensuring you remain relevant and in touch. With each new job you will naturally develop in experience and grow as a freelance copywriter, but it's important to ensure this growth draws from sources beyond your own writing.
The danger in this profession is that you're isolated. Usually you will not work with other copywriters; instead your interaction will be with businesses who know little about writing copy – that's why they're hiring you! If you're not careful this process can become like a runner with a bag over his head – unleashing plenty of energy, but soon losing his sense of direction. And if he's not careful, running off a cliff.
It's tempting to feel once you've completed your training, that's it – you've triumphed over the learning and now you just need to apply it. However, as great as the Copywriting Apprentice course is, it can only ever be a primer. It sets you up to begin your copywriting career with confidence and credibility, but there is a huge world of information out there and it's constantly changing. You need to stay in touch with this and keep growing as a copywriter.
There isn't a single copywriter in the country who doesn't need to do this – no matter how experienced – because the world of marketing is forever evolving and what worked a year ago may not be the best approach today. Tap into all the information you can to ensure you know how Google's algorithms are changing, what the new advice on best practice for email campaigns is, which examples of copy are getting the marketing world talking, and on and on and on…
How do you do this? The easiest way is to join Twitter and follow other copywriters – there's actually a great community out there. Twitter will soon 'learn' you like following copywriters and will suggest new ones to add to your list. You'll find they share links to interesting articles or discussions and you can also follow their blogs.
One of the most popular is Copyblogger, which offers excellent insights into current issues and ideas applying to a wide range of copy. You'll get news on the latest developments and changes to Google straight from the horse's mouth at the Google Webmaster Central Blog, but keep in mind this is Google's mouthpiece. It's intended to be helpful but it's not going to flag up the potential downsides of algorithm changes, so you need to hunt around for the latest comments about this on independent blogs.
You should, of course, be contributing to these online conversations yourself and writing your own blog is a good excuse for research into the latest thinking about your chosen topics. And whilst the internet is clearly the source for the most current information, don't neglect the many excellent books on copywriting – there's a great deal of wisdom and experience waiting to be tapped.
As an ongoing process you should also be nosing into any copy you find, deconstructing what other writers have done and keeping examples of anything you think is successful. You should create a filing system into which you can gather and organise these examples, so when it comes to a new case study, for instance, you can quickly put your hands on examples you thought were inspiring. This applies electronically as well, with folders of powerful websites and emails.
And, of course, you can pop back to the graduate section of the Copywriting Apprentice Learning Gateway! You'll always be welcome.
Copywriting is such a fascinating career not only because of the variety of businesses you will deal with, but because it's a constantly changing field in itself. Never allow the demands of the former to overwhelm your determination to keep up to speed with the latter. Your success will depend upon being on top of your game, so be sure your copy-shots are never wide of the mark because you hadn't noticed everyone else moving the goalposts!
I hope you've found this series useful and I wish you the very best of luck with your new copywriting business!
[…] Five Things to Act on when Becoming a Freelance Copywriter – Part 5 from @NexusWords http://t.co/ebeWG86I […]
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Spanish formula one driver Fernando Alonso made an unofficial visit to Ferrari's factory at Maranello and went for a spin in a 458 Italia on Friday. As the driver is still fulfilling outstanding responsibilities to Renault, the team he represented last season, the visit could not be termed official. This means he has to wait before the official presentation by Ferrari.
Alonso, the 28 year old driver from Spain and two time world champion, also had a conversation with the technicians of the Ferrari team. He also met Ferrari president Luca di Montezemolo for about half an hour.
Alonso has moved over to Ferrari for the 2010 season after a disappointing season last year with Renault as he finished in 9th place in the drivers' standings with 26 points while Renault finished 8th in the team standings. Both his championship wins in the 2005 and 2006 seasons came while he was Renault.