bluuebunny/crossref_metadata_2025 huggingface dataset:
The Personal Threat of Environmental Problems as Predictor of Environmental Practices
Authors: Baldassare Mark , Katz Cheryl
Published: March 2007

In the 1990 Orange County (CA) Annual Survey, residents who perceive that environmental problems pose a very serious threat to their health and well-being are more likely to engage overall in environmental practices and, specifically, to recycle, conserve water, buy environmentally safe products, and limit their driving. Personal environmental threat is a better predictor of overall environmental practices than are demographic variables and political factors. Perceived environmental threat is highest among younger residents, women, liberals, and Democrats. Future directions for research on perceived environmental threat in particular, and environmental concern in general, are discussed.
Promoting Source Reduction Behavior
Authors: De Young Raymond , Duncan Andrew , Frank Jeffrey , Gill Nancy , Rothman Shereen , Shenot John , Shotkin Andrea , Zweizig Miriam
Published: March 2007

In a study of the conservation behavior of 103 grocery shoppers in Chelsea, Michigan, an information and prompting strategy was used to test various rationales for adopting source reduction behavior. The experimental intervention consisted of mailing an educational pamphlet to participants. The experimental design included four treatment groups: a control and three others. These three other treatment groups each received a pamphlet giving environmental, economic, or a combination of environmental and economic rationales to reduce waste at the source. From data collected in pre-and postintervention survey instruments, it was shown that both environmental and economic rationales for practicing source reduction led to significant increases in reported source reduction behavior. Additionally, the type of conservation behavior promoted (e.g., toxics use reduction) and the location in which it is practiced (i.e., at home, at a store) were found to have an impact on the success of the interventions. Participants were more likely to adopt home-based source reduction of nontoxics over either store-based activities or activities involving toxics use reduction.
Farmers' Environmental Attitudes and Behavior
Authors: Vogel Stefan
Published: March 2007

This paper contributes to the debate about attitudes and behavior of farmers in respect to the environment. The empirical base comprises a survey of 2,095 farmers in Austria. A complex model of environmental attitudes in the agricultural sector has been developed. Using path analysis, this model was confronted with the survey data both to test it and to explore some major questions of the current environmental debate. An important finding is the strong influence that practical knowledge and personal experience have on the farmer's behavior. Another major result of the model in comparison with other studies is the strong relationship derived between atfitude and behavior. The discussion of the study results considers links between socioeconomic, cognitive, and other contextual factors that form and influence farmers' environmental attitudes and behavior.
Connecting to the Information Age
Authors: Rollet Edouard
Published: March 2007

The European Union's communications policy has had mitigated results in addressing issues related to the Information Age. On one hand, deregulation had the positive outcome of building a unified market, with corporations capable of challenging the supremacy of the United States. On the other hand, deregulation has followed the US model and has ignored the European concept of interventionism, which helps safeguard diversity and pluralism that could be threatened by ultraliberalism. National interests and diversity of standpoints constitute a major obstacle for the success of the EU's communication policy. However, one might remain optimistic in view of some of the EU's important actions that have been achieved through cooperation. The strong, self-endowed leadership of the European Commission succeeded in responding to one of the EU's major challenges: overcoming a slow policy-making process that would be particularly inappropriate, considering the fast-paced nature of modern communications.
Geographic Distance and Us Newspaper Coverage of Canada and Mexico
Authors: Wu Haoming Denis
Published: March 2007

This case study examines the influence of geographic distance on news coverage of Canada and Mexico in 13 newspapers across the US from 1990 to 1996. The number of news stories about Mexico is found to be highly related to the distance to either the Mexican or the Canadian border. Yet the correlation between news stories about Canada and geographic distance is not statistically significant. When the total space is controlled, the correlations between distance and coverage about both countries turn out to be highly significant.
Making Chinese Journalists for the Next Millennium
Authors: Wu Wei , Weaver David H.
Published: March 2007

The study is based on a national survey of 1052 Chinese journalism students conducted in late 1996. It aims to develop a detailed profile of Chinese journalism students and to examine their professional socialization process in becoming the next generation of journalists in China. It also compares the professional values and attitudes of these students with those of practicing journalists in China. We find that, overall, Chinese students' college experiences play a more important role than their demographic characteristics in their professionalization, but the values that students bring to college interact with their socialization there to produce their professional values. Evidence from this survey shows some positive signs in Chinese students' perceptions of professional roles, but there are also some questionable trends in their professionalization. The article discusses some of these problems and their possible causes. It also provides some suggestions for future research on journalistic education in China.
Toward new global development
Authors: Mohan Brij
Published: March 2007

But there remains also the truth that every end in history necessarily contains a new beginning; this beginning is the promise, the only 'message' which the end can ever produce. Beginning, before it becomes a historical event, is the supreme capacity of man; politically, it is identical with man's freedom. (Arendt, 1979: 478-9)
A Fantasy Theme Analysis of Peter Senge’s Learning Organization
Authors: Jackson Bradley G.
Published: March 2007

When it was first articulated in The Fifth Discipline, Peter Senge’s vision of the learning organization was one of a number of competing conceptions. This article examines what it was about Senge’s vision that enabled it to catch on and be assimilated so rapidly and pervasively into everyday business discourse. The method used in this study is fantasy theme analysis, a dramatistically based method of rhetorical criticism developed by Ernest Bormann that is rooted in symbolic convergence theory. The analysis reveals four interrelated fantasy themes that form the dramatic building blocks of the rhetorical vision of the learning organization. The article examines the organizational and rhetorical strategies that Senge has deployed to sustain widespread interest in his vision.
Elastic Properties of Hollow-Sphere-Reinforced Composites
Authors: Lee K.J. , Westmann R.A.
Published: March 2007

This paper is concerned with determining the elastic properties of a composite material composed of hollow spherical inclusions em bedded in a matrix. Both inclusions and surrounding material are taken to be isotropic and elastic.

As the result of a straightforward extension of Hashin's work, upper and lower bounds have been developed for the gross shear modulus of the composite. In addition, a closed form expression is presented for the gross bulk modulus of the material. Numerical results have been presented illustrating the effect of wall thickness of the inclusion upon the elastic constants of the composite. As illus trated by example, control of the properties and geometry of the inclusions permits "design" of a material with prescribed elastic behavior.
Membrane Motion of a Thin, Single Layer, Generally Orthotropic, Cylindrical Shell
Authors: Reuter Robert C.
Published: March 2007

A membrane theory for thin, single layer, generally orthotropic, cylindrical shells experiencing harmonic, axi-symmetric motion is established. Shear-coupling in the plane of the middle surface of the shell results in coupled motion occurring in three dispersive modes of propagation. Long and short wavelength velocity limits in the three modes are analogous to those of an isotropic shell, however, the short wavelength limits are reversed in the first and second modes. Three discrete frequencies occur for which: (1). motion is predominantly radial; (2). motion becomes uncoupled in the first and second modes; (3). the type of wave changes from extension-shear to shear-extension (or vise-versa) for most off-angle orientations. These events occur within the range of wavelengths, established in the membrane theory for isotropic shells, which render the theory accurate. When the shell is specially orthotropic, the in-plane motion is uncoupled; the first mode is a non-dispersive shear mode, while the second and third are dispersive extensional modes.
The Charpy Impact Energy of Boron-Aluminum
Authors: Prewo Karl M.
Published: March 2007

The notched Charpy impact energy of boron-aluminum composites has been determined as a function of specimen orientation, fiber type, matrix composition and fabrication conditions. Both boron fiber and silicon carbide coated boron fiber have been used with 1100, 6061, 2024, 5052 and 5056 aluminum alloys It has been demonstrated that impact energy values in excess of 30 joules (22 ft-lbs) can be achieved and that high levels of energy are maintained without loss in composite axial or transverse strength.
Optimal Experimental Measurements of Anisotropic Failure Tensors
Authors: Wu Edward M.
Published: March 2007

The resolution of the components of strength tensors derived from experimental data is discussed. It is shown that the variations in the non- interaction components are independent of the tension-compression strength ratios and magnitudes and their relative scatter can be related directly to the scatter in the engineering strength. The variation in the interaction component F12, is dependent on both the magnitude of the biaxial strength and the magnitude of F12; it has no well defined relative scatter and only its absolute resolution can be determined from experi mental scatter. Optimal experiments for F12 using tubular specimens are discussed. Optimal biaxial stress ratios using compression-internal pressure and tension-torsion tests are discussed and experimentally demonstrated.
A Boundary Layer Theory - Part I: Laminated Composites in Plane Stress
Authors: Tang S.
Published: March 2007

The boundary layer theory of plane stress in isotropic elasticity devel oped by Reiss and Locke is extended here to the laminated composites, In the boundary layer region, equations are separated into two problems, i.e., torsion problem and plane strain problem. These two problems are coupled through the compatibility equations as well as the continuity condition at the interfaces of the laminates. This formulation provides a tool to obtain analytical solutions to predict the two interlaminar shear stresses as well as the normal or "peel" stress.
Alternate Hybrid-Stress Elements for Analysis of Multilayer Composite Plates
Authors: Spilker R.L. , Chou S.C. , Orringer O.
Published: March 2007

Two quadrilateral-shaped multilayer plate bending/stretching elements based on the assumed-stress hybrid finite-element model are presented. These elements may be applied to the analysis of fiber composite plates and shells composed of an arbitrary number of layers and arbitrary mate rial properties and fiber direction within each layer. Both elements incor porate the effects of transverse shear by including the transverse shear stresses τ xz and τyz, and by assuming independent rotations of the normals to the plate midsurface, so that normals to the midsurface in the un deformed state need not be normal to the midsurface after deformation. In the formulation of an element based on the assumed-stress hybrid model, the stress distribution in the interior of the element is expressed in terms of a finite number of stress parameters such that equilibrium is satisfied, and the displacement distribution on the boundary of the element is expressed in terms of generalized nodal displacements such that interelement displacement compatibility is maintained. The principle difference between the two elements presented is the level of approxima tion incorporated into the stress and displacement assumptions. For one element the stresses within each layer are related to a set of stress param eters within that layer, and the boundary displacement assumption allows for independent cross-sectional rotations within each layer (and is thus capable of modeling the severe cross-sectional warping often associated with thick laminated plates). For the other element, the stresses within each layer are related to a set of stress parameters associated with the entire laminate, and the boundarv displacement assumption allows for a uniform rotation of the cross section of the laminate (not necessarily normal to the plate midsurface).

To assess the behavior of the two elements, two laminated composite plate example problems are considered, for which analytic solutions are available. The accuracy of predicted stress and displacement results obtained by using the two hybrid elements are compared with the exact solutions for cases involving both thick and moderately thick plates. Com parisons of the relative accuracy and computing efficiency of the two elements are presented, and the limitations on the use of each element are also discussed.
Nonlinear Response of Composite Material Structures
Authors: Craddock James N. , Zak Adam R. , Majerus John N.
Published: March 2007

This paper describes an experimental and a theoretical investigation of structural response of composite, fiber-reinforced materials. The objective of this study is to develop a theoretical model which can predict the response of the composite material based on the behavior of the individual material components. The model is used to predict the response of lam inated, cylindrical models, and the calculated results are compared with experimental data. In the experimental study a number of six-ply cylin drical shells were subject to internal pressure all the way up to failure. The loading was performed in a specially constructed test fixture which per mitted pressurization of the cylinders with a minimum amount of end constraints. The pressure was applied by combustion of a small amount of propellant. The deformation of the specimens was measured in the longi tudinal, the circumferential, and the radial directions and these readings were correlated with the pressure-time history. The experimental results show a pronounced nonlinear response of the cylinders even at relatively small deformations. In order to explain this behavior, a theoretical model was developed, which accounts for large transverse stresses in the plies and permits gradual plastic yield of the matrix material. This model is com bined with finite-element method of stress analysis and it is shown that the experimentally observed nonlinear behavior can be explained by this approach.
Applications of the Average Stress Failure Criterion: Part II — Compression
Authors: Nuismer R.J. , Labor J.D.
Published: March 2007

Results are presented for the compressive fracture strength of several Gr/Ep (AS/3501-5) laminates containing countersunk holes with both loaded and unloaded fasteners in place. Finite element stress analyses are presented which approximate the countersink geometry and the elastic contact problem. The average stress failure criterion is successfully used to predict the observed strengths in all cases considered.
A Reusable Sandwich Beam Concept for Composite Compression Test
Authors: Gruber Mark B. , Overbeeke Johannes L. , Chou Tsu-Wei
Published: March 2007

A reusable sandwich beam for compression testing has been developed. Testing was performed to determine the longitudinal compressive modulus and ultimate compressive strength of a Kevlar® /glass intermingled hybrid composite. Results using this test method are reported and compared with results obtained using the IITRI test method.
Failure Strength of Nonlinearly Elastic Composite Laminates Containing a Pin Loaded Hole
Authors: Chang Fu-Kuo , Scott Richard A. , Springer George S.
Published: March 2007

A method is presented for calculating the failure strengths and failure modes of composite laminates containing a pin loaded hole for materials exhibiting nonlinearly elastic behavior. The analysis follows that proposed by Chang, Scott, and Springer for linearly elastic composites with two notable exceptions: a) the shear stress-shear strain relation in each ply is taken to be nonlinear with the form proposed by Hahn and Tsai, and b) the Yamada-Sun failure criterion is modified to include nonlinear effects. Numerical results, generated using a nonlinear finite element scheme, were compared to data. These comparisons show that for laminates exhibiting nonlinear behavior the present analysis provides the failure strengths and failure modes more accurately than the previous method employing a linear stress-strain analysis.
On the Prediction of the Initiation of Delamination in a [0/90]S Laminate with a Circular Hole
Authors: Ericson K. , Persson M. , Carlsson L. , Gustavsson A.
Published: March 2007

Two approaches to predict the initiation of delamination at the edge of a hole in a [0/90]S graphite/epoxy laminate under in-plane compression loading are presented. The first approach, which is used to analyse interlaminar stresses in a laminate without delamination, employs singular finite elements at the edge of the hole, the strength of the singularity being varied around the edge. The second analysis is a fracture mechanics analysis based on the strain energy release rate. Both analyses predict that the risk of delamination is highest about 60° away from the loading direction.
On the Impact of Initially Stressed Composite Laminates
Authors: Sun C.T. , Chen J.K.
Published: March 2007

The impact response behavior of initially stressed composite laminates is investigated using the finite element method. An experimentally established contact law is incor porated into the finite element program. The Newmark time integration algorithm is used for solving the time dependent equations of the plate and the impactor. Numerical results, including the contact force history, deflection, and strain in the plate, are presented. Effects of impact velocity, initial stress, and the mass and size of the impactor are discussed.
The Characterization of Boron/Aluminum Composite in the Nonlinear Range as an Orthotropic Elastic-Plastic Material
Authors: Kenaga D. , Doyle J.F. , Sun C.T.
Published: March 2007

Off-axis uniaxial testing is used to characterize the nonlinear behavior of boron/ aluminum composite. An orthotropic elastic-plastic formulation is used.
Elastic-Plastic Analysis of Boron/Aluminum Composite Under Constrained Plasticity Conditions
Authors: Rizzi S.A. , Leewood A.R. , Doyle J.F. , Sun C.T.
Published: March 2007

The modelling of Boron/Aluminum composites under constrained plasticity is in vestigated. Testing is performed on a tapered specimen and one with a centered circular hole. A finite element analysis is compared with the experimental strain gage results.
The Mechanics of Prepreg Conformance
Authors: Gutowski T.G. , Bonhomme L.
Published: March 2007

Experiments are reported and mathematical models are developed to describe the me chanics of prepreg conformance to a substrate. Two distinctly different behaviors are identi fied for graphite epoxy prepregs, called: 1) pressure driven lay-up behavior, and 2) surface tension driven lay-up behavior. In the first case it is shown that there is a force-velocity superposition principle that applies to the lay-up parameters. In the second case, the ap plied force is unimportant. For both cases an upper bound on the lay-up speed is observed and mathematical models are developed to describe the phenomena. Reasons for the dif ferent behavior, and applications to lay-up of prepregs in machine tools are discussed.
Characterization of Damage and Fracture Processes in Short Fiber BMC Composites by Acoustic Emission
Authors: Faudree M. , Baer E. , Hiltner A. , Collister J.
Published: March 2007

Acoustic emission (AE) and scanning electron microscope (SEM) techniques have been coupled with mechanical deformation to study the damage and fracture mechanisms in a short fiber BMC composite. During tensile deformation the initial damage process observed in the SEM was the formation of small cracks at filler particles and glass fibers. Damage due to this mechanism was identified with acoustic emission in the 40 dB ampli tude range. Onset of this damage mechanism occurred at very low strains and damage con tinued to accumulate until fracture. At higher strains the small cracks were observed in the SEM to coalesce to form large cracks spanned by pulled-out fibers. Formation of the large cracks was identified with a burst of AE in the 70 dB amplitude range just prior to fracture. Crack growth during stress relaxation fracture or in single loading tests occurred in a dis continuous manner due to the fiber reinforcement.
An Experimental Investigation into the Strength of Angle Ply GRP Tubes under High Rate of Loading
Authors: Al-Salehi F.A.R. , Al-Hassani S.T.S. , Hinton M.J.
Published: March 2007

Static and dynamic burst tests were carried out on filament wound glass reinforced plas tic (GRP) tubes. The tubes were loaded under internal pressure with minimum end con straints. In the static tests, the pressure was supplied to the rig by a Losenhausen servo hydraulic intensifier system, whereas in the dynamic tests a drop hammer apparatus was used to generate the pressure, giving medium strain rates of the order of 10 sec-1. Higher strain rate burst tests were carried out using suitable explosives. A system for fast data acquisition was developed so that during each test, the internal pressure and strains in the central section of the specimen could be recorded, the data processed and the results auto matically plotted in the form of pressure-time, strain-time and stress-strain curves. Some high speed photographs were also taken during the dynamic bursting of the tubes to record the failure mode for each winding angle.

The results showed no significant change in the strength, strain to failure or the secant modulus of the tubes at strain rates up to about 10 sec-1, typical to the drop hammer apparatus. There was, however, a large increase in burst strength as the strain rate was further increased to 150 sec-1 during the explosive tests. The values of strain to failure were also increased, thus leaving the secant modulus of the tubes virtually unaltered.
Ply-Slip During the Forming of Thermoplastic Composite Parts
Authors: Tam Albert S. , Gutowski Timothy G.
Published: March 2007

A model for the ply-slip deformation behavior of a laminate composite is presented which allows prediction of the stresses, displacements, and strains developed during the forming process. The model takes into account the viscous nature of the matrix and the stress relaxation achievable via ply slippage. The stress response is inherently time dependent and is strongly affected by the forming rate. Results calculated for the isother mal three point bending of a unidirectional lay-up agree well with previous experimental data. An important parameter, the maximum system time constant, is identified and related to the material properties and part geometry. Comparisons with experiments and simulation results for nonisothermal forming are also discussed.
Time Dependent Behavior of Laminated Composites at Elevated Temperatures
Authors: Ha Sung K. , Springer George S.
Published: March 2007

Models are presented for describing the time dependent viscoelastic and viscoplastic stress-strain relationships of unidirectional fiber reinforced thermoset matrix composites exposed to elevated temperatures. For Fiberite T300/976 graphite-epoxy com posite the constants in the stress-strain relationships were determined from data obtained in four point bend tests over the range 75 to 350°F. A procedure is also described which, together with the stress-strain models developed in this study, can be used to calculate the stresses and strains in loaded multidirectional laminates at high temperatures. Strains in loaded multidirectional Fiberite T300/976 laminates were measured as a function of time at temperatures varying from 75 to 350°F. Strains calculated by the models were compared to these data, and good agreements were found between the analytical and experimental results.
The Crush Behavior of Pultruded Tubes at High Strain Rates
Authors: Thornton P.H.
Published: March 2007

The effect of fiber diameter, trigger geometry and section geometry on the crush response of pultruded glass fiber reinforced plastic tubes, made with either polyester or vinyl ester resin, was determined at crush rates from 2.1 x 10-4 m/s to — 15 m/s. The rate dependence of the specific energy for the polyester resin tubes was positive, whereas that for the vinyl resin tubes could be either positive or negative, depending upon the par ticular tube geometry. Increases in the specific energy absorption, previously observed in quasi-static loading, caused by changes in the crush trigger geometry, were found also for dynamic loading. Reductions in the fiber diameter by one half (nominal), for the same glass content, decreased the specific energy by up to ∼20%. Differences in the resin affect the quasi-static crush resistance, the vinyl ester resin tubes having a significantly higher specific energy than that of the polyester resin tubes. These differences tend to diminish for dynamic crush. Fiber delamination occurs more profusely under dynamic loading con ditions, and it is suggested that a crush mode change occurs on passing from quasi-static to dynamic loading. A tendency to crush in an unstable manner was found for some square sections under dynamic loading, possibly due to the accumulation of crush debris in the tube interior.
Tensor Transformations and Failure Criteria for the Analysis of Fiber Composite Materials Part II: Necessary and Sufficient Conditions for Laminate Failure
Authors: Christensen Richard M.
Published: March 2007

Necessary and sufficient conditions for composite lamina failure within a laminate are derived from the separate criteria for fiber failure and for matrix failure.
Low-Velocity Impact Response of Foam-Core Sandwich Composites
Authors: Nemes J.A. , Simmonds K.E.
Published: March 2007

The low-velocity impact response of foam-core sandwich composites with fiberglass/epoxy face sheets is treated by a combination of computational and experimental methods. Linear elastic constitutive models are used for the face sheets and epoxy bond layer in conjunction with a foam constitutive model that includes nonlinear hardening plasticity and coupling between volumetric and deviatoric deformation. A transient finite- element code, utilizing four-noded uniform strain quadrilaterals, is used to explicitly solve the equations for balance of mass and momentum. The resulting deformation histories are compared to the experimental results and show qualitative agreement. The computed transverse shear stresses are used to correlate ultrasonic measurement of damage in the core/epoxy interface. Comparison of the plate stiffness prior to and after impact illustrates the effect of damage on subsequent behavior.
Residual Stresses in a Composite with Continuously Varying Young's Modulus in the Fiber/Matrix Interphase
Authors: Jayaraman Krishnan , Reifsnider Kenneth L.
Published: March 2007

The incorporation of a realistic interphasial region into the micromechani cal analyses of composite systems is critical to the understanding of composite behavior. The interphase is usually modeled as a homogeneous region, despite the fact that it may have spatial property variations. A representative volume element with three cylinders (concentric cylinder assemblage) is considered here for the determination of local thermal stresses in a composite. Three different expressions are used to simulate the Young's modulus variations in the interphase, while the Poisson's ratio and coefficient of thermal expansion of the interphase region are chosen to be constant. The governing field equa tions in terms of displacements are solved in closed form. It is found that, though the solu tion is "dilute," the Young's modulus variations have a distinct effect on the local thermal stresses.
Crippling of Titanium Matrix Composite Stiffeners
Authors: Fogarty John H.
Published: March 2007

Using established principles of laminate buckling theory and post buckling load redistribution, a theory is derived for crippling analysis of specially ortho tropic or very nearly specially orthotropic laminated composite stiffeners. Results from testing of SCS-6/Ti-15-3 titanium matrix composite (TMC) stiffener segments are also presented and show good correlation with theoretical predictions. The testing program in cludes three different layups, three different geometries, and a repetition of two tests for each possible geometry/layup combination for a total of 18 tests. The results of the theory are presented in the form of easy-to-use design curves.
Strength Prediction and Optimization of Composites with Statistical Fiber Flaw Distributions
Authors: Zhanjun Gao  , Reifsnider Kenneth L. , Carman Greg
Published: March 2007

For continuous fiber reinforced polymeric composites the process domi nating tensile strength is fiber fracture. This phenomena results in stress concentrations in adjacent fibers over some distance which is directly associated with the ineffective length. This length is the controlling factor in the theory of bundle strength for polymer-based composites. The associated stress concentration factor, C, is normally associated with fracture propagation in both the matrix and surrounding fibers, and should also be in cluded as an important part of any representation of the mechanism controlling tensile fail ure in fibrous composites. In this paper, we combine bundle theory with the mechanics of local stress concentration in the development of a mechanistic representation of tensile strength. The resulting analysis is applied to numerical studies of the influence of micromechanical properties and irregular fiber spacing on the tensile strength, and a dis cussion of optimal design parameters for composites.
On the Failure Mechanisms in Laminate Compression Specimens and the Measurement of Strengths
Authors: Wung E.C.J. , Chatterjee S.N.
Published: March 2007

Simple analytical models are utilized to quantify the effects of specimen geometry and layup, imperfections (initial curvature of specimens) as well as elastic and inelastic material properties on buckling or bending induced failures. Other possible mechanisms including ply or micro buckling and end effects are also considered. Results are correlated with test data from different specimen types and conclusions are drawn regarding the mechanism which appears to govern the failure in each case. Data obtained from a test program conducted as a part of the present study as well as those available in literature are utilized for this purpose. Some recommendations are made regarding choice of test specimens and an approach is suggested for determining the "true compressive strength" from test data, especially for unidirectional composites.
Effects of Casting Conditions and Deformation Processing on A356 Aluminum and A356-20 Vol. % SiC Composites
Authors: Rozak G.A. , Lewandowski J.J. , Wallace J.F. , Altmisoglu A.
Published: March 2007

An A356 aluminum-20 vol. % SiC composite and an unreinforced alloy were processed using either sand casting or squeeze casting techniques, followed by hot deformation processing via swaging. Hot deformation processing was conducted to reduc tions of 33, 50, 73, 90 and 95 % for both the unreinforced and composite specimens prior to aging to peak strength. The evolution of the microstructure and tensile properties were evaluated for the cast materials in each of the hot worked conditions. The squeeze cast composite exhibited a more homogeneous microstructure in comparison to the sand cast microstructure, while hot deformation produced additional changes in the microstructure of the composite. Deformation processing of the sand cast composite resulted in banding of the aluminum and the SiC particles within the microstructure; such features were not apparent in the squeeze cast microstructure. The tensile strength of the squeeze cast materials exceeded those of the sand cast for both the unreinforced and composite forms, while increased amounts of deformation were shown to improve the ductility of the com posite. Swaging to 95 % reduction produced an increase in the reduction of area from 2.7 % to 14.2 % for the squeeze cast composite and from 0.1 % to 11.0 % for the sand cast compos ite. The results are discussed in light of the microstructural changes accompanying the various processes employed.
Modeling Creep in Thermoplastic Composites
Authors: Chung Ilsup , Sun C.T. , Chang I.Y.
Published: March 2007

A creep model for unidirectionally reinforced fiber composites was devel oped based on a one-parameter potential function. The same potential function was used to describe plastic flow and time-dependent creep deformation. The material constants in the model were determined by using the uniaxial tension test of off-axis coupon specimens. In terms of effective stress and effective creep strain, the anisotropic creep behavior can be given by a stress-dependent master creep curve irrespective of loading direction relative to fiber orientation. DuPont's AS4/PEKK thermoplastic composites were used in the creep experiment. Results for both unidirectional and laminated composites were presented.
Synergistic Thermal-Moisture Damage Mechanisms of Epoxies and Their Carbon Fiber Composites
Authors: Zheng Q. , Morgan R.J.
Published: March 2007

Experiments were conducted measuring the changes in weight of neat epoxy resins and carbon fiber reinforced epoxy composites during immersion in distilled water in temperature range from 0.5°C to 80°C. From the weight change data, the values of maximum moisture contents and diffusion coefficients were determined. Systematic studies were carried out on the "reverse thermal effect" for both neat resin and composite. A critical temperature was observed below which the materials exhibit normal behavior (the rate of absorption of water into epoxy resin increases with increasing temperature) and once the materials saturated with water at temperatures above it, the reversibility of reverse thermal effect was observed. A possible mechanism involving moisture-induced elastic cavities is suggested to explain the effect. The effects of water on Tg, thermal expan sion and yield stress of neat epoxy resin were studied.
Pace of Life, Punctuality, and Coronary Heart Disease in Six Countries
Authors: Levine Robert V. , Bartlett Kathy
Published: March 2007

Cross-cultural differences in attitudes and behaviors concerning time, punctuality, and pace of life, and the relationship of these measures to coronary heart disease, were investigated in a series of studies in Japan, Taiwan, Indonesia, Italy, England, and the United States. Study 1 found that public clocks were most accurate in the most economically developed countries (Japan and the United States) and least accurate in the least developed country (Indonesia). Study 2 measured average walking speed during main business hours. Walking speed was fastest in Japan and slowest in Indonesia. Also, subjects in smaller cities tended to walk slower than those in larger cities. Study 3 measured average time taken to complete a standardized postal request. Work speed was again fastest in Japan. Italy was slowest. There were high intercorrelations within cities for the above three measures. Next, the findings from the first three studies were related to incidence of coronary heart disease. Despite the lack of available mortality statistics for Taiwan and Indonesia, some interesting trends questioning the cross-cultural generality of the relationship between Type A behaviors and coronary heart disease emerged. Finally, in a questionnaire study conducted mostly in the United States, the relationship between scores on a measure of Type A behavior characteristics and subjects' reported frequency of lateness, feelings after being late, perceptions of what constitutes late and early, attributions for lateness, and ratings of the importance of punctuality in a business person and in a friend were investigated.
Hofstede's Culture Dimensions
Authors: Hofstede Geert , Bond Michael H.
Published: March 2007

Ng et al. (1982) collected data among students in nine Asian and Pacific countries using a modified version of the Rokeach Value Survey. Their data were reanalyzed by the present authors through an ecological factor analysis that produced five factors. Six of the countries covered also appear in Hofstede's (1983) extended study of work-related values among employees of a multinational corporation in 53 countries and regions. For the overlapping countries a correlation analysis was done between the five factor scores of the Ng et al. reanalysis and the four dimension scores of Hofstede. This correlation analysis revealed that each of Hofstede's dimensions can be distinctly identified in the Ng et al. data as well. This article is presented as an example of synergy between different cross-cultural studies.
Sleep Habits in the Elderly
Authors: Domino George
Published: March 2007

Little information is available on the normal aspects of sleep in the elderly, and almost none from a cross-cultural perspective. The subjects of this study consisted of 562 elderly from Mexico, Spain, Venezuela, and the United States, who completed a 55-item Sleep Questionnaire, yielding scores on nine scales. Statistically significant differences between cultural groups on five scales and significant sex differences on three scales were obtained. These differences may reflect sample differences or cultural differences related to such themes as concern with death and attitudes toward sleep.
Sex and Culture in Burnout and Coping among Human Service Professionals
Authors: Etzion Dalia , Pines Ayala
Published: March 2007

In this study, burnout and coping were investigated among 503 human service professionals in the United States and Israel. A standardized self-report measure was used to determine burnout levels. The frequencies of use of 12 different coping strategies were assessed via a self-report questionnaire, differentiating coping efforts along two dimensions (active/inactive; direct/ indirect). A two-way analysis of variance yielded significant main effects for culture and for sex, but no significant interaction. It was found that Americans reported feeling more burned out than Israelis, and women reported feeling more burned out than men. As for coping, women reported using indirect and inactive coping strategies more than men, and Americans reported using them more than Israelis. The pattern of correlation between coping and burnout suggested that active-direct strategies were more effective in coping with stress than were the inactive and/or indirect behaviors. The discussion focuses on how sex role stereotypes and cultural values mediate the availability of various coping strategies, and thus affect the subjective experience of burnout.
Why Regimes Create Disorder
Authors: Ferrara Federico
Published: March 2007

Research on protest and repression has shown that state coercion may result in increased mobilization or effectively deter further challenges. The nature of dissident responses to repression is largely context-based. In Burma, as the military regime faced a massive uprising, although brutal coercion failed to quell the rebellion in August 1988, it succeeded in suppressing the democratic movement only a few weeks later. Such a difference is explained in terms of contextual transformations resulting from the government's strategic adaptation. Specifically, by suspending the supply of social order, the regime presented the population with Hobbes's dilemma. Forced to choose between dictatorship and anarchy, the Burmese people overwhelmingly defected from the democratic movement and reluctantly accepted the reestablishment of a highly oppressive order. This analytic narrative seeks to contribute to the understanding of the relationship between protest and repression and enrich the literature on strategic adaptation.
A Theory of Bounded Deterrence
Authors: Doran Charles F.
Published: March 2007

According to this analysis, the deterrent relationship is bounded by two concepts, the nuclear threshold and the level of unacceptable damage, each of which is a function of the utility of the threatened objective to both deterrer and aggressor. The crucial assumption of the theory, that the utility of foreign policy objectives varies with the objective, is tested empirically regarding American attitudes toward security commitments. Five variables loading on three dimensions predict the utility of these commitments. A consequence of the theory is that it calls into doubt government assertions that the nuclear umbrella provides as much security to allies as to the deterrer.
The Belfast Workshop
Authors: Doob Leonard W. , Foltz William J.
Published: March 2007

The Belfast Workshop brought together 56 Catholic and Protestant citizens of Belfast during August 1972. Through an intervention design which combined Tavistock and National Training Laboratory group dynamics approaches, a team of American social scientists attempted to assist the 56 to learn about their behavior in organized groups and better to understand their political opponents' situation. The workshop sought further to provide a protected setting wherein groups might explore modes of intercommunal cooperation that could later be implemented back in Belfast. This article describes the rationale behind the intervention, the methods employed, and the difficulties such enterprises encounter. It also offers a preliminary report on what was accomplished and suggests implications for long-term solutions of the conflict.
Simulation Methodologies in Experimental Research on Negotiations by Representatives
Authors: Klimoski Richard J.
Published: March 2007

This paper reviews recent experimental (primarily social-psychological) research on intergroup conflict resolution with an emphasis on methodology. Specifically, it focuses on the creation of conflict forces and representational role obligations in simulations. The resulting typologies clarify the numerous strategies used by investigators. The paper calls for a systematic evaluation of these strategies as researchers appear to be unaware of their potential impact. It is also argued that selected arrangements described would help to enhance simulations to be congruent with a model of intergroup bargaining processes.
The Impact of Binding Interest Arbitration on Negotiation and Process Outcome
Authors: Subbarao A.V.
Published: March 2007

The subject of conflict and the methods of conflict resolution are of central importance to collective bargaining. The major concern of policy makers and of negotiators in public sector labor relations, in particular, is to find a method of conflict resolution which not only would avoid work stoppages but also would be compatible with free collective bargaining. Binding interest arbitration is suggested as the method of conflict resolution which would accomplish both the purposes. Four systems of binding interest arbitration-namely, the final-offer-selection, last-offer-by-issue, open-award, and compromise—award—are being experimented with in several negotiation situations Some labor relations practitioners have expressed experiences in contradiction with the theoretical expectations of the impact of these four systems of binding interest arbitration on negotiation process and outcome This experimental study confirms the theoretical expectations, particularly of the final-offer-selection and last-offer-by-issue systems. The former system generates genuine negotiations, while the latter subverts collective bargaining.
Objective versus Subjective Aspects of Interpersonal Relations between Jews and Arabs
Authors: Amir Yehuda , Ben-Ari Rachel , Bizman Aharon , Rivner Miriam
Published: March 2007

Research has already revealed a number of variables affecting attitude change resulting from interethnic contact. These variables are invariably defined according to objective criteria (e.g., socioeconomic status). The present study concentrated on the effects of status and treatment, objectively as well as subjectively defined and measured, on attitudes of 302 West Bank Arabs working in 13 major industrial plants in Israel. Findings indicate that objective and subjective treatment of Arab workers correlates positively with attitude change towards Israeli Jews. However, workers with higher status at the plants showed less favorable attitudes toward Israelis. Arabs who subjectively evaluated their status at the plant as high expressed more positive attitudes towards Israelis than those who evaluated their status as low. Theoretical and applied implications of the findings are discussed.
Do Outbreaks of War Follow a Poisson-Process?
Authors: Houweling H. W. , Kuné J. B.
Published: March 2007

Richardson's finding that the distribution of war outbreaks in time conforms to the Poisson distribution has been repeated over and over again. In this article, we argue that the close correspondence between the two distributions does not imply that the mechanism generating the data is the Poisson process. Because the time sequence is broken down in Richardson's analysis, his finding does not imply that war outbreaks follow a distinct pattern in time. The Parzen test on arrival times revealed that war outbreaks are not generated by a Poisson random process.
International Conflict and Military Expenditures
Authors: Seiglie Carlos
Published: March 2007

This article analyzes the two-stage problem a country faces in first choosing the optimal amount of arms to acquire and then deciding whether it can improve upon the allocation that emerges after the first stage by engaging in a military conflict. A model is introduced based on the concept of economic externality to generate conflict situations in the first stage. Then comparative static results are derived by varying the parameters of this model, for example, the rate of technological progress in the military sector and the rate of economic growth, and examining whether the conflict situation improves or worsens as the social welfare of the nations change accordingly. Uncertainty is then introduced and the results are analyzed. Finally, the last part explores the conditions under which the conflict situations presented in the first stage actually lead to the outbreak of war.
Testing the Waters
Authors: Ward Hugh
Published: March 2007

Individuals often fail to cooperate because they are not sufficiently reassured that others involved share their desire for reciprocal cooperation. Such situations may be seen as Assurance games. The existing literature fails to examine the problems posed by lack of information about others' preferences, either assuming that information is perfect, or that it may be made perfect by mutual verbal reassurances. This article shows that in sequential public goods supergames, players with Assurance preferences may gather information about others' preferences from their game moves, and that it may pay them to take risks of short-term losses in order to do so. The most efficient information-gathering strategy for such a player is cooperation. The model helps us understand why players of Assurance often appear to take risks in order to “test the waters” with cooperative moves, and why the problem posed for collective action is sometimes successfully resolved.