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Based on the general formula, which depends on the length and difficulty of the test, the number of respondents and the number of ability levels, this study aims to provide a closed formula for the adaptive tests with medium difficulty (probability of solution is p = 1/2) to determine the accuracy of the parameters for each item and in the case of calibrated items, determine the required test length given number of respondents.

Empirical results have been obtained on computerized or multistage adaptive implementation. Simulation studies and classroom/experimental results show that adaptive tests can measure test subjects’ ability to the same quality over half the test length compared to linear versions. Due to the complexity of the problem, the authors discuss a closed mathematical formula: the relationship between the length of the tests, the difficulty of solving the items, the number of respondents and the levels of ability.

The authors present a closed formula that provides a lower bound for the minimum test length in the case of adaptive tests. The authors also present example calculations using the formula, based on the assessment framework of some student assessments to show the similarity between the theoretical calculations and the empirical results.

With this formula, we can form a connection between theoretical and simulation results.

Computational elastica theory is used to model a simple test for the bending properties of fabrics. This test, entitled the “CLOAK” test, was designed to offer practical experimental advantages over the established cantilever bending, of bending length, test. Computational elastica theory offers a routine method for modelling fabrics in cantilever bending. In this case, the CLOAK test is simulated and shown to be equivalent to both the bending length test and to a related test method proposed in the 1960s.

As one natural fiber, yak cashmere has been used more and more widely on textile processing due to its excellent warmth retention property. Yarn spinning is the first and the most important step of textile processing. Yarn spinning is closely related to the fiber properties. That is, for giving the optimization spinning process of one new fiber, the properties of the new fiber should be studied firstly. Meanwhile, during the studying of the properties of the new fiber, comparative analysis method was usually used. That is, the property of the new fiber was common comparatively analyzed with other fibers. During the comparative analysis, the spinning process can be optimized. Therefore, in the paper, the properties of the yak cashmere were studied in detail and comparatively analyzed.

The brown yak cashmere, cyan yak cashmere, white cashmere fiber, purple cashmere fiber, cyan cashmere fiber, camel hair fiber and mohair fiber, were chosen as the samples. The fiber length, fineness, strength, curls, moisture regain, mass specific resistance, surface morphology, infrared spectrum, melting behavior, thermal weight loss, friction, x-ray, were tested and comparatively analyzed.

It is shown that the compositions of yak cashmere and cashmere are similar, and makes the physical properties of yak cashmere and cashmere fiber similar. Comparing with the mohair, camel hair and cashmere fiber, the average length of yak cashmere is smaller and the dispersion of length distribution is larger, and the dispersion of yak cashmere strength is larger, which makes the yarn spinning of yak cashmere difficult, especially the high count pure yarn. However, comparing with the mohair, camel hair and cashmere fiber, the friction coefficient and friction effect of yak cashmere is larger, and yak cashmere fiber has relatively less curls and larger crimp rate and crimp recovery rate, and can improve the fiber spinnability.

In the paper, taking the brown yak cashmere, cyan yak cashmere, white cashmere fiber, purple cashmere fiber, cyan cashmere fiber, camel hair fiber, mohair fibers as the samples, the properties of the yak cashmere were studied in detail. The fiber length, fineness, strength, curls, moisture regain, mass specific resistance, surface morphology, infrared spectrum, melting behavior, thermal weight loss, friction, x-ray, were tested and comparatively analyzed. The studies can establish foundation for the optimization of the yak cashmere spinning process, and also can provide information for the end uses of the fiber.

The purpose of this paper is to elucidate the stress-strain relationships of single-jersey knitted fabrics from uniaxial tensile test followed by deformation behavior using finite element analysis. In order to elaborate the study, high, medium and low tightness knitted fabrics were selected and deformation of fabrics analyzed in course, wales and bias directions (0, 45 and 90 degrees).

This study focussed on uni-axial tensile test of produced test samples using Instron 6021 tester and a development of single-jersey knitted loop model using Auto Desk Inventor software (ADI). The knitted fabric material properties and knitted loop model was imported to ANSYS 12.0 software.

Due to structural changes the tightness and thickness of knitted fabric decreases with increase in loop length The tensile result shows maximum breaking strength at course direction (13.43 kg f/mm2 at 2.7 mm) and maximum extension at wales direction (165.77 kg f/mm2 at 3.3 mm). When the loop length increases, the elongation of fabrics increased and load carrying capacity of fabrics reduced. The Young's modulus, Poisson's ratio and shear modulus of fabrics reduced with increase in loop length. The deformation of fabrics increased with increase in loop length. The increase in loop length gives large amount of structural changes and it is due to slacking or jamming in loops and loosening in dimensions. When comparing the deformation results, the variation within the fabric is higher and structural damage little more when increasing the loop length of the fabric.

From ANOVA test, stress and strain distribution was statistically significant among course, wales and bias directions at 95 percent confidence level. The values got from Instron test indicates that testing direction can alter its deformation. In deformation analysis, comparing both experimental and prediction, high amount of structural changes observed in wales direction. The used tetrahedral elements can be used for contact analysis with high accuracy. For non-linear problems, consistent approach was proposed which makes the sense to compare with experimental methods. The proposed model will make possible developments and the preliminary validation tests shows good agreement with experimental data.

Presents a study of the relationships between fabric drapeability and seam allowance, seam position and seam directions in terms of drape coefficient, bending length and draped profile. Concludes that by the results obtained from the sewn specimens, the draped profile of a fabric without a seam can be predicted and proved by extended experimental work. Suggests that the knowledge gained from present research on fabric drape will be useful in the determination of the drape profile on garment in practical use. Moreover, it has significant value in paving the way for establishing clothing CAD systems, and sheds light on fundamental mechanisms operating in fabric drape behaviour.

The purpose of this paper is to study the correlation between the dynamic features of the running-in attractor and the wear particle group, so as to characterize the running-in attractor by means of the wear particle group.

Wear particles are collected in phased wear experiments, and their dynamic features are investigated by the equivalent mean chord length L. Then, the correlation between the equivalent mean chord length L and the correlation dimension D of the running-in attractor is studied.

In the wear process, the equivalent means chord length L first decreases, then remains steady, and finally increases, this process agrees with the increase, stabilization and decrease of the correlation dimension D. Therefore, the wear particle group has a dynamic nature, which characterizes the formation, stabilization, and disappearance of a running-in attractor. Consequently, the dynamic characteristics and evolution of a running-in attractor can be revealed by the wear particle group.

The intrinsic relationship between the wear particle group and the running-in attractor is proved, and this is advantageous for further revealing the dynamic features of the running-in attractor and identifying the wear states.

ONE of the activities of the Deutsche Versuchsanstalt für Lufthfahrt has, naturally, been directed to the development of special instruments adapted for the peculiar needs of the experimental work carried out at Adlershof. Arrangements have recently been made whereby a wide range of these instruments is available in England and they can now be obtained from International Technical Developments, Ltd., of Thames House, Millbank, London, S.W.I.

This study aims to shed light on the experience of the United Arab Emirates (UAE) in balancing three main pillars: the environmental criteria, the reduction of CO₂ emissions and the economic growth. Based on the environmental Kuznets curve (EKC) framework, it will assess the causal relationship between economic indicators such as gross domestic product (GDP) per capita, trade openness and energy use and environmental indicators such as CO₂ emissions.

The analysis relies on a period of 40 years (1981–2020) where data is extracted from the World Bank database. This study uses the unit root test for time series stationarity, the optimal lag length test, the “Johansen” test for co-integration and the vector error correction model.

The paper concludes to two major findings. On a short-term basis, CO₂ emissions and economic indicators are negatively correlated, whereas on a long-term basis, there is no association between CO₂ emissions and economic indicators in the UAE.

The research ends with important recommendations. It illustrates the importance of rationalizing the use of primary resources and the necessity to embrace successful and efficient policies in the energy production.

More specifically, UAE is urged to address the problem of CO₂ emissions in the electricity sector and increase awareness of the use of environmentally friendly processes in the transport and industrial sectors. While setting their economic agendas, UAE are encouraged to meet environmental criteria and invest in renewable energy projects such as “Shams 1”, the largest solar power plant outside of Spain and the USA.

The current study is significant in its research on the environmental impact of economic development, trade openness and energy use policies in the UAE. It uses CO₂ emissions as an environmental proxy and evaluates the environmental policies adopted in the UAE to reduce its impact.

Observes that the timely and sufficient provision of industrial space helps to facilitate industrial activities that contribute to economic growth. An understanding of the interactions between the economy and the real estate market is useful to local policy decision makers and developers in ensuring the ready availability of industrial space without incurring unnecessary excess vacancy. This article hopes to build upon existing research by applying cointegration analysis and error‐correction modelling to examine the supply dynamics of Singapore’s industrial property market. The presence of long‐run equilibrium relationships between industrial property supply, economic and real estate variables is tested using cointegration analysis. The persistence profile examines the effect of system‐wide shocks to the cointegration relations to determine whether they are true cointegrating vectors.

Cognitive ability tests demonstrate strong relationships with job performance, but have several limitations; notably, subgroup differences based on race/ethnicity. As an alternative, the purpose of this paper is to develop a working memory assessment for personnel selection contexts.

The authors describe the development of Global Adaptive Memory Evaluation (G.A.M.E.) – a working memory assessment – along with three studies focused on refining and validating G.A.M.E., including examining test-taker reactions, reliability, subgroup differences, construct and criterion-related validity, and measurement equivalence across computer and mobile devices.

Evidence suggests that G.A.M.E. is a reliable and valid tool for employee selection. G.A.M.E. exhibited convergent validity with other cognitive assessments, predicted job performance, yielded smaller subgroup differences than traditional cognitive ability tests, was engaging for test-takers, and upheld equivalent measurement across computers and mobile devices.

Additional research is needed on the use of working memory assessments as an alternative to traditional cognitive ability testing, including its advantages and disadvantages, relative to other constructs and methods.

The findings illustrate working memory’s potential as an alternative to traditional cognitive ability assessments and highlight the need for cognitive ability tests that rely on modern theories of intelligence and leverage burgeoning mobile technology.

This paper highlights an alternative to traditional cognitive ability tests, namely, working memory assessments, and demonstrates how to design reliable, valid, engaging and mobile-compatible versions.