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Investigation was carried out on how the tensile and related properties of Siro yarns, spun from two separated rovings of different types of materials, were affected by the twist factor and draft. Comparison on Siro yarns and two-fold yarns of the same linear density and twist factor revealed that the former was better in tensile strength and related properties. The Siro yarns are believed to be able to bear extra tension during manufacturing processes such as weaving and knitting.

This chapter reviews the history of regulation and deregulation in international air transport and discusses the positive impacts of deregulation and open skies on the tourism sector in the Asia Pacific region. The Hong Kong–Bangkok market was examined, which shows that the granting of the fifth freedom rights has given the two places sufficient air service provisions to build tourism. Future reforms in air transport such as relaxing ownership restrictions and expanding air freedoms rights are explored.

Globally, diversity awareness is a vital aspect of schools. International perspectives on special education invite consideration of views of diversity and disability. Increased diversity in schools and communities has become commonplace and a 21st century norm. This chapter begins with an overview of diversity and multiculturalism. Disability as a category of diversity is explored. Special education and interventions designed to support the educational opportunities for students with disabilities are discussed. A framework for international perspectives on disability and intervention is described.

To develop a reliable methodology and procedure of simulating the jet‐in‐crossflow using the current turbulence models and numerically investigate the cooling performance of a new scheme for the engines of next generation.

A new advanced film cooling scheme is proposed based on the literature survey and a systematic methodology developed to successfully predict the right level of heat transfer in the CFD simulation of film cooling.

The proposed cooling scheme gives considerable lower heat transfer coefficient at the centerline in the near hole region than the traditional cylindrical hole, especially at a high blowing ratio when traditional cylindrical hole undergoes liftoff.

The number of cooling holes in the computational domain is limited by the speed of the computers used.

The new methodology can be used to numerically test new cooling schemes in the design of turbine blades and to provide useful information/data under actual working conditions to design engineers.

This paper provides some useful information on the simulation of film cooling in terms of the performance of different turbulence models and wall treatments and also sends some valuable messages regarding the design of cooling scheme of turbine blades to the technical community.

Maintaining the turbine blade’s temperature within the safety limit is challenging in high-pressure turbines. This paper aims to numerically present the conjugate heat transfer analysis of a novel approach to mini-channel embedded film-cooled flat plate.

Numerical simulations were performed at a steady state using SST k – ω turbulence model. Impingement and film cooling are classical approaches generally adopted for turbine blade analysis. The existing film cooling techniques were compared with the proposed design, where a mini-channel was constructed inside the solid plate. The impact of the blowing ratio (M), Biot number (Bi) and temperature ratio (TR) on overall cooling performance was also studied.

Overall cooling effectiveness was always shown to be higher for mini-channel embedded film-cooled plates. The effectiveness increases with increasing the blowing ratio from M = 0.3 to 0.7, then decreases with increasing blowing ratio (M = 1 and 1.4) due to lift-off conditions. The mini-channel embedded plate resulted in an approximately 21% increase in area-weighted average overall effectiveness at a blowing ratio of 0.7 and Bi = 1.605. The lower uniform temperature was also found for all blowing ratios at a low Biot number, where conduction heat transfer significantly impacts total cooling effectiveness.

To the best of the authors’ knowledge, this study presents a novel approach to improve the cooling performances of a film-cooled flat plate with better cooling uniformity by using embedded mini-channels. Despite the widespread application of microchannels and mini-channels in thermal and fluid flow analysis, the application of mini-channels for blade cooling is not explored in detail.

The purpose of this paper is to investigate the film cooling effectiveness and heat transfer coefficient in a flat plate with two rows of rectangular injection holes.

Experimental and numerical investigation of film cooling effectiveness in a flat plate with two rows which are rectangular injection holes. The liquid crystal technique has been used for measuring the heat transfer coefficients on the mixture region. Three injection holes in model are in a single row. The holes are rectangular cross section and they are 9 × 6.5 mm. The injection holes are inclined at 30° along the mainstream direction. The blowing ratios are from 0.5 to 2.0. The experiments and their computational models are established to investigate its effects at the 330 and 340 and 350 K injection temperatures and the different blowing ratios.

The results show that the film cooling effectiveness and heat transfer coefficient of a given flat plate surface, both along the mainstream and lateral direction, depend on the optimum selection of parameters. In this study, the highest effectiveness is determined at a blowing ratio of 0.5. Further increasing the ratio results in reverse effect on the film cooling effectiveness.

It is the fist time the film cooling effectiveness is compared at the rectangular injection holes with two rows as experimental and numerical.

The purpose of this paper is to propose a new approach to further obtain reduced Hamiltonian equations for certain nonlinear cases of finite amplitude.

Chebyshev polynomials are introduced to best approximate the primitive exact wave equations.

New results are derived for certain nonlinear cases of finite amplitude. Furthermore, ranges of applicability are determined in conjunction with the error analyses for various cases. In particular, the new structure can give a new highly accurate formula for determining the wave forces of the offshore structures.

New reduced Hamiltonian equations for nonlinear surface gravity waves have been derived for certain cases of finite amplitude for the first time. And the new structure can give a new highly accurate formula for determining the wave forces of offshore structures. These results extend the usual results for weakly nonlinear surface waves to nonlinear surface waves over certain finite ranges.

In this paper, the author proposed an optimization design for a step-stress accelerated life test (SSALT) with two stress variables for the generalized exponential (GE) distribution under progressive type-I censoring.

In this paper, two stress variables were considered. Progressive censoring and accelerated life testing were used to reduce the time and cost of testing. It was assumed that the lifetimes of the test units followed a GE distribution. The effects of changing stress were considered as a cumulative exposure model. A log-linear relationship between the scale parameter of the GE distribution and the stress was proposed. The maximum likelihood estimators and approximate and bootstrap confidence intervals (CIs) for the model parameters were obtained. An optimum test plan was developed using minimization of the asymptotic variance (AV) of the percentile life under the usual operating condition.

According to the simulation results, the bootstrap CIs of the model parameters gave more accurate results than approximate CIs through the length of CIs. The sensitivity analysis was performed to illustrate the effect of initial estimates on optimal values that has been studied. Simulation results also indicated that the optimal times were not too sensitive to the initial values of parameters; thus, the proposed design was robust.

In most studies, only one accelerating stress variable is used. Sometimes accelerating one stress variable does not yield enough failure data. Thus, two stress variables may be needed for additional acceleration. In this paper, two stress variables are considered. The inclusion of two stress variables in a test design will lead to a better understanding of the effect of two simultaneously operating stress variables. Also, the author assumes that the failure time of the test units follows a GE distribution. It is observed that the GE distribution can be used quite effectively to analyze lifetime data in place of gamma, Weibull and log-normal distributions. Also, most studies in this field have focused on the derivation of optimum test plans. In this paper, the author examined the estimation of model parameters and the optimization of the test design. In this paper, the asymptotic and bootstrap CIs for the model parameters are calculated. In addition, a sensitivity analysis is performed to examine the effect of the changes in the pre-estimated parameters on the optimal hold times. For determining the optimal test plan, due to nonlinearity and complexity of the objective function, the particle swarm optimization (PSO) algorithm is developed to calculate the optimal hold times. In this method, the research speed is very fast and optimization ability is more.

In many countries, innovation in building design for improving energy performance, reducing CO2 emissions and minimizing life cycle cost has received much attention for sustainable development. This paper investigates the importance of optimization tools for enhancing the design performance in the early stages of Vietnam's cooling-dominated buildings in hot and humid climates using an integrated building design approach.

The methodology of this study exploits the non-dominated sorting genetic algorithm (NSGA-II) optimization algorithm coupled with building simulation to research a trade-off between the optimization of investment cost and energy consumption. Our approach focuses on the whole optimization problem of thermal envelope, glazing and energy systems from preliminary design phases. The methodology is then tested for a case study of a non-residential building located in Hanoi.

The results show a considerable improvement in design performance by our method compared to current building design. The optimal solutions present the trade-off between energy consumption and capital cost in the form of a Pareto front. This helps architects, engineers and investors make important decisions in the early design stages with a large view of impacts of all factors on energy performance and cost.

This is one of the original research to study integrated building design applying the simulation-based genetic optimization algorithm for cooling-dominated buildings in Vietnam. The case study in this article is for a non-residential building in the north of Vietnam but the methodology can also be applied to residential buildings and other regions.

This paper aims to investigate the wear behaviors of aged metal matrix composites and of the as-cast Al-Si alloy by using a pin-on-disk wear testing machine at room temperature.

Hypoeutectic (Al-7Si) alloy reinforced with low volume fractions of SiC particles (SiC_p) and graphite (Gr) particles were prepared by the stir-casting process. It was found that the addition of 9 Wt.% of SiC_p and 3 Wt.% of Gr particles conferred a beneficial effect in reducing the wear rate of the composites.

The worn-out surfaces of the specimens were examined using scanning electron microscopy (SEM); the extensive micro cracking occurs on the surface of the Al-7Si alloy tested at lower loads. The growth of these microcracks finally led to the delamination of the base alloy surface. The reinforcements (SiCp and Gr) particles tended to reduce the extent of plastic deformation in the surface layer, thereby reducing extensively the occurrence of micro cracking in the composites.

From the results, it is revealed that the quantity of wear rate was less for aged specimens compared to the as-cast specimens. The worn-out surfaces were studied using electron dispersive spectroscopy, and wear debris was analyzed using SEM.