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The purpose of this study is to study the simultaneous effect of embedded reverting microchannels on the cooling performance and mechanical strength of the electronic pieces.

In this study, a new configuration of the microchannel heat sink was proposed based on the constructal theory to examine mechanical and thermal aspects. Initially, the thermal-mechanical behavior in the radial arrangement was analyzed, and then, by designing the first reverting channel, maximum temperature and maximum stress on the disk were decreased. After that, by creating second reverting channels, it has been shown that the piece is improved in terms of heat and mechanical strength.

Having placed the second reverting channel on the optimum location, the effect of creating the third reverting channel has been investigated. The study has shown that there is a close relationship between the maximum temperature and maximum stress in the disk as maximum temperature and maximum stress decrease in pieces with more uniform distribution channels.

The proposed structure has decreased the maximum temperature and maximum thermal stresses close to 35 and 50%, respectively, and also improved the mechanical strength, with and without thermal stresses, about 40 and 24%, respectively.

In the present research, a numerical investigation is carried out to study the fluid flow and heat transfer in a double-pipe, counter-flow heat exchanger exploiting metal foam inserts partially in both pipes. The purpose of this study is to achieve the optimal distribution of a fixed volume of metal foam throughout the pipes which provides the maximum heat transfer rate with the minimum pressure drop increase.

The governing equations are solved using the finite volume method. The metal foams are divided into different number of parts and positioned at different locations. The number of metal foam parts, their placements and their volume ratios in each pipe are sought to reach the optimal conditions. The four-piece metal foam with optimized placement and partitioning volume ratios is selected as the best layout. The effects of the permeability of metal foam on the Nusselt number, the performance evaluation criteria (PEC) and the overall heat transfer coefficient are investigated.

It was observed that the heat transfer rate, the overall heat transfer coefficient and the effectiveness of the heat exchanger can be improved as high as 69, 124 and 9 per cent, respectively, while the highest value of PEC is 1.36.

Porous materials are widely used in thermo-fluid systems such as regenerators, heat sinks, solar collectors and heat exchangers.

Having less pressure drop than fully filled heat exchangers, partially filled heat exchangers with partitioned metal foams distributed optimally enhance heat transfer rate more economically.

The purpose of this paper is to provide an attempt to evaluate the risk-adjusted performance of international mutual funds using the risk statistic generated by the mean absolute deviation (MAD) and promote the ability of portfolio managers and investors to make the logical decisions for selecting different funds using the new optimized measures.

This study evaluates the performance of 50 international mutual funds using optimized risk-adjusted measures by the MAD over the monthly period 2001-2010. Using 50 linear programming models, the MAD is first computed by the linear programming models, and then seven performance measures of Treynor, Sharpe, Jensen’s α, M2, information ratio (IR), MSR, and FPI are optimized and proposed by the MAD to evaluate the mutual funds.

The empirical evidence detects that the MAD is an important determinant to evaluate the funds’ performance. Using the MAD statistic, this paper shows that new optimized measures are mostly over-performed by the benchmark index; in addition, these optimized measures have close correlation with each other. The results, therefore, detect the importance of using new optimized measures in evaluating the mutual funds’ performance.

The result of this study can be directly used as an initial data for decision of investors and portfolio managers who are seeking the possibility of participating in the global stock market by the international mutual funds.

This paper is the first study which optimizes the variance of returns in the MAD framework for each fund to propose new seven optimized measures of Treynor, Sharpe, Jensen’s α, M2, IR, MSR, and FPI.

The purpose of this paper is to appraise the risk‐adjusted performance of international mutual funds using measures generated by the optimized variance (OV), and to promote ability of portfolio managers and investors in making logical decisions.

This study appraises the performance of 65 international mutual funds via the optimized risk‐adjusted measures during monthly period of 2001‐2010. Using 65 linear programming models, the OV is calculated to optimize the standard deviation of any funds. Then, another model is run to get the OV of market index. Consequently, seven optimized performance measures namely Treynor, Sharpe, Jensen's alpha, M‐squared, information ratio (IR), MSR, and FPI along with the optimized leverage factor are proposed to evaluate the performance of these mutual funds. Finally, the optimized measures are used to evaluate the funds during pre and post‐crisis periods in order to compare the funds' performance over the crisis periods.

The empirical evidence detects which OV, as measured by the Markowitz's linear programming model, is an important determinant in the performance evaluation measures. Using OV statistic and also its standard deviation, this paper shows that new optimized measures are mostly over‐performed rather than the benchmark index; in addition these optimized measures have close correlation with the conventional performance measures. The evidence shows that the average of the optimized measures during crisis has the lowest performance in comparison with other research periods. The results therefore highlight the importance of using the new optimized measures along with the conventional measures in the evaluation of mutual funds' performance.

It can be worthwhile to compare the optimized measure and also the conventional measures in identifying their superior measures.

The result of this study can be directly used as initial data to make decision by investors and portfolio managers who are seeking the possibility of participating in the global stock market through international mutual funds.

This paper is one of the first studies that optimizes the variance of return for any fund to suggest four optimized measures of Sharpe, IR, MSR, and FPI, and then proposes a new linear programming model to get OV of market index in introducing four optimized new measures of Treynor, M‐square, Jensen's alpha, and leverage factor.

The purpose of this paper is to propose a new and improved version of arbitrage pricing theory (APT), namely, downside APT (D-APT) using the concepts of factors’ downside beta and semi-variance.

This study includes 163 stocks traded on the Malaysian stock market and uses eight macroeconomic variables as the dependent and independent variables to investigate the relationship between the adjusted returns and the downside factors’ betas over the whole period 1990-2010, and sub-periods 1990-1998 and 1999-2010. It proposes a new version of the APT, namely, the D-APT to replace two deficient measures of factor's beta and variance with more efficient measures of factors’ downside betas and semi-variance to improve and dispel the APT deficiency.

The paper finds that the pricing restrictions of the D-APT, in the context of an unrestricted linear factor model, cannot be rejected over the sample period. This means that all of the identified factors are able to price stock returns in the D-APT model. The robustness control model supports the results reported for the D-APT as well. In addition, all of the empirical tests provide support the D-APT as a new asset pricing model, especially during a crisis.

It may be worthwhile explaining the autocorrelation limitation between variables when applying the D-APT.

The framework can be useful to investors, portfolio managers, and economists in predicting expected stock returns driven by macroeconomic and financial variables. Moreover, the results are important to corporate managers who undertake the cost of capital computations, fund managers who make investment decisions and, investors who assess the performance of managed funds.

This paper is the first study to apply the concepts of semi-variance and downside beta in the conventional APT model to propose a new model, namely, the D-APT.

The purpose of this paper is to provide the modified measures of risk-adjusted performance evaluation of Malaysian mutual funds using the downside risk concepts, and promote the ability of managers and investors in making logical decisions under the market asymmetry condition.

This study focusses on the performance evaluation of Malaysian mutual funds using eight modified measures of Sharpe, Treynor, M2, Jensen’s α, information ratio (IR), MSR, SPI, and leverage factor. These modified measures use the downside systematic risk and semi-standard deviation instead of systematic risk and conventional standard deviation, respectively, to evaluate the performance of Malaysian mutual funds over the period 2000-2011.

The results indicate that the conventional measures of performance evaluation do not have a crucial influence on the relative evaluation of mutual funds. Three modified measures of Sharpe, Treynor, and M2 have a high correlation with the conventional Sharpe measure and can be used instead of the conventional Sharpe measure. Since, two modified measures of Treynor and M2 display a high rank correlation coefficient with the conventional Treynor measure, they can be replaced with this traditional measure. In addition, two modified IR and MSR measures along with the modified SPI and conventional SPI show very high rank correlation coefficients in relation to each other. The results also document a modified leverage factor less than one for all funds. It can be concluded that the strategy of un-levering the investor’s holding must be followed.

The empirical evidence of this study can be utilized as inputs in the process of decision-making by different types of investors who are interested in participating especially in Malaysian stock market and generally in global stock market under the market asymmetry condition.

The contribution of this study is to modify five measures of M2, IR, MSR, FPI, and leverage factor in the downside risk framework which is a work on a rather under-researched area.

This paper aims to evaluate the risk‐adjusted performance of Malaysian mutual funds using optimized drawdown risk measures (ODRMs) based on modern portfolio theory, and to represent the results in a manner which is easily understood by average investors and portfolio managers.

This study evaluates the performance of 70 Malaysian mutual funds using risk‐adjusted returns during 2000‐2011. The ODRM is primarily calculated by 70 linear programming models, consequently seven new optimized risk‐adjusted performance measures including Sharpe, Treynor, M‐squared, Jensen's alpha, information ratio (IR), MSR, and FPI are proposed to evaluate these funds.

The results of this study have several implications. First, the ODRM can be an alternative risk measure to optimize the selection of mutual funds. Second, it proposes new seven optimized performance measures of Sharpe, Treynor, M‐square, Jensen's alpha, IR, MSR, and FPI. These measures help fund managers to evaluate the performance of Malaysian mutual funds optimally. Third, No‐Islamic funds have the upper performance than Islamic funds based on the results of optimized measures and robustness tests. Fourth, the majority of surveying funds over‐perform the benchmark indexes.

The research evidence reported by this study can be utilized as input in the process of decision making by small and average investors and portfolio managers who are seeking the possibility of participating in Malaysian stock market by mutual funds.

This paper is the first study that optimizes the drawdown risk measure to evaluate the performance of Malaysian mutual funds and propose seven optimized measures, Sharpe, Treynor, M‐Square, Jensen's alpha, IR, MSR, and FPI.

This paper aims to evaluate the risk‐adjusted performance of the management styles of Malaysian mutual funds using nine modified performance evaluation measures generated by the maximum drawdown risk measure (M‐DRM) based on the modern portfolio theory. The purpose is to report the findings in a manner which is realizable by the average investors and portfolio managers.

This paper evaluates the performance of more than 400 Malaysian mutual funds using risk‐adjusted returns over the two sub‐periods of 2000‐2005 and 2006‐2011. The M‐DRM, as a different measure from downside risk, is applied to improve nine risk‐adjusted performance measures of Sortino, Treynor, M‐squared, Jensen's alpha, information ratio (IR), MSR, upside partial ration (UPR), FPI, and leverage factor. It proposes a new single‐factor model to test the maximum drawdown beta and alpha in the M‐DRM framework.

The evidence clearly indicates that the replacement framework in terms of MDB, the maximum drawdown beta, and the maximum drawdown CAPM can be replaced by the conventional frameworks in terms of MVB, beta, and the CAPM and also MSB, downside beta, and D‐CAPM for modifying nine performance evaluation measures from the management styles of Malaysian mutual funds.

The research evidence reported in this paper can be applied as input in the process of decision making by small and average investors and portfolio managers who are seeking the possibility of participating in the global stock market through mutual funds.

This paper is the first study to estimate a new regression model in the M‐DRM framework to evaluate the performance of Malaysian mutual funds. In addition, it proposes nine modified performance evaluation measures in the M‐DRM framework for the first time.

Risk assessment is a very important step toward managing risks in various organizations and industries. One of the most extensively applied risk assessment techniques is failure mode and effects analysis (FMEA). In this paper, a novel fuzzy multiple-criteria decision-making (MCDM)-based FMEA model is proposed for assessing the risks of different failure modes more accurately.

In this model, the weight of each failure mode is considered instead of risk priority number (RPN). Additionally, three criteria of time, cost and profit are added to the three previous risk factors of occurrence (O), severity (S) and detection (D). Furthermore, the weights of the mentioned criteria and the priority weights of the decision-makers calculated by modified fuzzy AHP and fuzzy weighted MULTIMOORA methods, respectively, are considered in the proposed model. A new ranking method of fuzzy numbers is also utilized in both proposed fuzzy MCDM methods.

To show the capability and usefulness of the suggested fuzzy MCDM-based FMEA model, Kerman Steel Industries Factory is considered as a case study. Moreover, a sensitivity analysis is conducted for validating the achieved results. Findings indicate that the proposed model is a beneficial and applicable tool for risk assessment.

To the best of authors’ knowledge, no research has considered the weights of failure modes, the weights of risk factors and the priority weights of decision-makers simultaneously in the FMEA method.

In recent decades, the student population in dormitories has increased notably, primarily attributed to the growing number of international students. Dormitories serve as pivotal environments for student development. The coordination and compatibility among students can significantly influence their overall success. This study aims to introduce an innovative method for roommate selection and room allocation within dormitory settings.

In this study, initially, using multi-attribute decision-making methods including the Bayesian best-worst method and weighted aggregated sum product assessment, the incompatibility rate among pairs of students is calculated. Subsequently, using a linear mathematical model, roommates are selected and allocated to dormitory rooms pursuing the twin objectives of minimizing the total incompatibility rate and costs. Finally, the grasshopper optimization algorithm is applied to solve large-sized instances.

The results demonstrate the effectiveness of the proposed method in comparison to two common alternatives, i.e. random allocation and preference-based allocation. Moreover, the proposed method’s applicability extends beyond its current context, making it suitable for addressing various matching problems, including crew pairing and classmate pairing.

This novel method for roommate selection and room allocation enhances decision-making for optimal dormitory arrangements. Inspired by a real-world problem faced by the authors, this study strives to offer a robust solution to this problem.