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This study aims to quantitatively identify the impact of major economic and political factors on the US apparel imports from its 15 major trading partners between 1995 and 2006.

Ordinary‐least‐square (OLS) regression under a gravity model framework was utilized to construct the analysis. The determinants of US apparel imports were determined and their significance and direction of change over the period were quantified.

First, the growths of GDP and population both in the USA and within its trading partners have been drivers of US apparel import growth, while greater geographic distance between a trading partner and the USA significantly impedes its exports to the USA. Second, the positive impact on the US apparel imports from the supplying country's infrastructure development, literacy rate and its language commonality with the USA shows that these factors are pivotal to being a competitive US apparel supplier. Finally, preferential market access is proven to be crucial for suppliers to increase apparel exports to the USA.

In future work, the impact of these factors on disaggregated apparel categories could be investigated. Some emerging issues such as non‐tariff barriers could be exploited.

The findings reveal that the US apparel sourcing decisions are made on the basis of many different costs, not only labour cost, but also economic condition, government policy, infrastructure, transport time and cost, language/culture commonality etc.

The study provides a springboard for empirically analyzing the US apparel imports under a gravity model framework. The conclusions are drawn based on solid quantitative evidence.

The dual-phase-lag (DPL) model and Lord-Shulman theory with one relaxation time are applied to study the effect of the gravity field, the magnetic field, and the hydrostatic initial stress on the wave propagation in a two-temperature generalized thermoelastic problem for a medium with an internal heat source that is moving with a constant speed. The paper aims to discuss this issue.

The exact expressions of the considered variables are obtained by using normal mode analysis.

Numerical results for the field quantities are given in the physical domain and illustrated graphically in the absence and presence of the gravity field as well as the magnetic field. Comparisons are made between the results of the two different models with and without temperature dependent properties and for two different values of the hydrostatic initial stress. A comparison is also made between the results of the two different models for two different values of the time.

In the present work, the author shall formulate a two-temperature generalized magneto-thermoelastic problem for a medium with temperature dependent properties and with an internal heat source that is moving with a constant speed under the influence of a gravity field and a hydrostatic initial stress. Normal mode analysis is used to obtain the exact expressions for the displacement components, thermodynamic temperature, conductive temperature, and stress components. A comparison is carried out between the considered variables as calculated from the generalized thermoelasticity based on the DPL model and the L-S theory in the absence and presence of a magnetic field as well as a gravity field. Comparisons are also made between the results of the two theories with and without temperature dependent properties and for two different values of hydrostatic initial stress. A comparison is also made between the results of the two different models for two different values of the time.

The purpose of this paper is to examine the relationship between bilateral country reputation and export volume to the country in which that reputation is held.

The unique bilateral data set consists of 861 country pairs. Country reputation measures are from a global survey, in which respondents in 20 countries rate the reputation for products and people of 50 other countries. This data set is then analyzed against actual export data for each country-pair using the well-established structural gravity model of international trade.

The authors find that each improvement in a world ranking of a country’s reputation for products (in a target country) is associated with a 2 percent increase in exports to that particular country; the effect is equivalent to the importing country decreasing a tariff by as much as 2.9 percent. Furthermore, the authors find that different aspects of country reputation – for its products and its people – attenuate distinct forms of uncertainty, and thereby stimulate export volume in distinct ways.

This study shows that the relationship between country reputation and export volume is a substantive and empirically valid topic of study. For public policy makers looking to stimulate exports to a specific country, improving their respective country’s reputation in that country appears to be a viable alternative to other levers (e.g. trade negotiations, free trade agreements). For business leaders at international companies, the findings suggest that companies may consider country reputation as a factor when choosing to which countries they wish to expand.

The notion that country reputation can contribute to aggregate export volume has intuitive appeal. Yet, aside from research on country-of-origin effects which has concentrated on the individual consumer level, the notion of country reputation contributing to aggregate effects has so far been based mostly on conjecture and anecdotal evidence. This is the only study to the authors’ knowledge that empirically tests this relationship using a bilateral measure of reputation as a determinant of export volume within one of the most successful empirical frameworks, the structural gravity model of international trade. The findings suggest that for many countries, their reputation may contribute to billions of dollars in export volume.

The purpose of this paper is to obtain a general solution to the field equations of generalized thermo-diffusion in an infinite thermoelastic body under the effect of gravity in the context of the dual-phase-lag (DPL) model. The half space is considered made of an isotropic homogeneous thermoelastic material. The boundary plane surface is heated by a non-Gaussian laser beam.

An exact solution to the problem is obtained using the normal mode analysis.

The derived expressions are computed numerically for copper and the results are presented in graphical form.

Comparisons are made with the results predicted by Lord-Shulman theory and DPL model for different values of time and in the presence and absence of gravity as well as diffusion.

The purpose of this paper is to design an adaptation algorithm to facilitate pointing in electronic interfaces by users with motor impairment.

First, the algorithm was optimized using a simulator, then the algorithm was validated through a user study involving seven motor‐impaired and six able‐bodied users and three different pointing devices.

The algorithm significantly reduces pointing time overall and most participants pointed quicker with the gravity well than without it.

The adaptation algorithm can significantly reduce pointing time for both motor and situational impairment.

To demonstrate, through numerical models, that it is possible to simulated low‐gravity phase change (melting), of an electrically conducting material (gallium), in terrestrial conditions via the application of electromagnetic fields.

A complete three‐dimensional mathematical formulation governing a phase change process in the presence of an electromagnetic field has been developed. In addition a comprehensive parametric study has been completed to study the various effects of gravity, Stefan number, Hartmann number and electromagnetic pressure number upon the phase change process.

The results show that the application of an electromagnetic filed can be used to simulate key melting characteristics found for actual low‐gravity. However, the resulting three‐dimensional flow field in the melted region differs from actual low‐gravity. The application of an electromagnetic field creates a flow phenomenon not found in actual low‐gravity or previously seen in two‐dimensional problems.

Future work may include the use of oscillating electromagnetic fields to enhance convection in energy storage systems in a low‐gravity environment.

The ability to suppress unwanted convective flows in a phase change process without the high magnetic fields necessary in magnetic field only suppression systems.

This work fills a void in the literature related to conducting fluids and the effects of magnetic and electromagnetic fields.

The purpose of this study is to examine theoretically the axisymmetric flow of a steady free-surface jet emerging from a tube for high inertia flow and moderate surface tension effect.

The method of matched asymptotic expansion is used to explore the rich dynamics near the exit where a stress singularity occurs. A boundary layer approach is also proposed to capture the flow further downstream where the free surface layer has grown significantly.

The jet is found to always contract near the tube exit. In contrast to existing numerical studies, the author explores the strength of upstream influence and the flow in the wall layer, resulting from jet contraction. This influence becomes particularly evident from the nonlinear pressure dependence on the upstream distance, as well as the pressure undershoot and overshoot at the exit for weak and strong gravity levels, respectively. The approach is validated against existing experimental and numerical data for the jet profile and centerline velocity where good agreement is obtained. Far from the exit, the author shows how the solution in the diffusive region can be matched to the inviscid far solution, providing the desired appropriate initial condition for the inviscid far flow solution. The location, at which the velocity becomes uniform across the jet, depends strongly on the gravity level and exhibits a non-monotonic behavior with respect to gravity and applied pressure gradient. The author finds that under weak gravity, surface tension has little influence on the final jet radius. The work is a crucial supplement to the existing numerical literature.

Given the presence of the stress singularity at the exit, the work constitutes a superior alternative to a computational approach where the singularity is typically and inaccurately smoothed over. In contrast, in the present study, the singularity is entirely circumvented. Moreover, the flow details are better elucidated, and the various scales involved in different regions are better identified.

The purpose of the chapter is to test the hypothesis that food safety (chemical) standards act as barriers to international seafood imports. We use zero-accounting gravity models to test the hypothesis that food safety (chemical) standards act as barriers to international seafood imports. The chemical standards on which we focus include chloramphenicol required performance limit, oxytetracycline maximum residue limit, fluoro-quinolones maximum residue limit, and dichlorodiphenyltrichloroethane (DDT) pesticide residue limit. The study focuses on the three most important seafood markets: the European Union’s 15 members, Japan, and North America.Our empirical results confirm the hypothesis and are robust to the OLS as well as alternative zero-accounting gravity models such as the Heckman estimation and the Poisson family regressions. For the choice of the best model specification to account for zero trade and heteroskedastic issues, it is inconclusive to base on formal statistical tests; however, the Heckman sample selection and zero-inflated negative binomial (ZINB) models provide the most reliable parameter estimates based on the statistical tests, magnitude of coefficients, economic implications, and the literature findings. Our findings suggest that continually tightening of seafood safety standards has had a negative impact on exporting countries. Increasing the stringency of regulations by reducing analytical limits or maximum residue limits in seafood in developed countries has negative impacts on their bilateral seafood imports. The chapter furthers the literature on food safety standards on international trade. We show competing gravity model specifications and provide additional evidence that no one gravity model is superior.

A novel approach using artificial neural networks (ANNs) for predicting temperature profiles evaluated 27 wells in the Gulf of Mexico. Two artificial neural network models were developed that predict the temperature of the flowing fluid at any depth in flowing oil wells. Back propagation was used in training the networks. The networks were tested using measured temperature profiles from the 27 oil wells. Both neural network models successfully mapped the general temperature‐profile trends of naturally flowing oil wells. The highest accuracy was achieved with a mean absolute relative percentage error of 6.0 per cent. The accuracy of the proposed neural network models to predict the temperature profile is compared to that of existing correlations. Many correlations to predict temperature profiles of the wellbore fluid, for single‐phase or multiphase flow, in producing oil wells have been developed using theoretical principles such as energy, mass and momentum balances coupled with regression analysis. The Neural Network 2 model exhibited significantly lower mean absolute relative percentage error than other correlations. Furthermore, in order to test the accuracy of the neural network models to that of Kirkpatrick’s correlation, a mathematical model was developed for Kirkpatrick’s flowing temperature gradient chart.

The purpose of this paper is to examine the effects of gravity variables and trade costs on China's export margins.

Following the structural gravity model with firm heterogeneity, the paper measures the extensive margins and intensive margins of China's export across 46 export destinations and estimates the linkage between export margins and its potential determinants.

The empirical results confirm the gravity relationship hold for bilateral trade and export margins. Furthermore, trade costs have different influence on extensive margins and intensive margins as the structural gravity model with firm heterogeneity expected. The paper also shows the rapid growth of China's export is mainly along the intensive margins which are increasing in fixed cost for export.

The paper contributes to the measurements of China's export margins and the empirical research on effects of trade liberalization on China's foreign trade.