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The purpose of this paper shows the effect of hot and humid weather conditions (HHWCs) on workers that has resulted in considerable loss in the construction industry, especially during the hottest periods due to decline in worker productivity (WP). Until the last few decades, there is very limited research on construction WP in HHWCs. Nevertheless, these studies have sparked interests on seeking for the most appropriate methods to assess the impact of HHWCs on construction workers.

This paper begins by reviewing the current measuring methods on WP in HHWCs, follows by presenting the potential impact of HHWCs on WP. The paper highlights the methodological deficiencies, which consequently provides a platform for scholars and practitioners to direct future research to resolve the significant productivity loss due to global warming. This paper highlights the need to identify the limitations and advantages of the current methods to formulate a framework of new approaches to measure the WP in HHWCs.

Results show that the methods used in providing real-time response on the effects of HHWCs on WP in construction at project, task and crew levels are limited. An integration of nonintrusive real-time monitoring system and local weather measurement with real-time data synchronisation and analysis is required to produce suitable information to determine worker health- and safety-related decisions in HHWCs.

The comprehensive literature review makes an original contribution to WP measurements filed in HHWCs in the construction industry. Results of this review provide researchers and practitioners with an insight into challenges associated with the measurements methods and solving practical site measurements issues. The findings will also enable the researchers and practitioners to bridge the identified research gaps in this research field and enhance the ability to provide accurate measures in HHWCs. The proposed research framework may promote potential improvements in the productivity measurements methods, which support researchers and practitioners in developing new innovative methods in HHWCs with the integration of the most recent monitoring technologies.

A finite element formulation for flexure of isotropic plates based on a recent refined theory is developed. The refined theory incorporates effects of transverse shear, transverse normal stress and transverse normal strain. The Galerkin finite element method was used to develop the finite element equations for both plate bending and inplane problems. The performance of the proposed finite element model was evaluated by solving problems of uniformly loaded thick plates with different support conditions. The results of the present formulation are compared with Mindlin/Reissner and elasticity solutions.

Outdoor localization is an important issue for many applications, such as autonomous mobile robotics and augmented reality. The purpose of this paper is to propose a budgeted dynamic exclusion heuristic based on signal phase shifts from multiple base stations.

The authors also propose an outdoor localization technique based on the particle filter for data fusion and present an overview of a potential target application of the proposed outdoor localization approach for the blind and visually impaired (BVI).

The combination of multiple sensor data tends to overcome the drawbacks of using one sensor technology in the localization process.

The novelty of the proposed approach stems from its ability to fuse data collected from different sensor technologies to converge to more accurate position estimation.

Developing an optimized project schedule that considers all decision criteria represents a challenge for project managers. The purpose of this paper is to provide a multi-objectives overall optimization model for project scheduling considering time, cost, resources, and cash flow. This development aims to overcome the limitations of optimizing each objective at once resulting of non-overall optimized schedule.

In this paper, a multi-objectives overall optimization model for project scheduling is developed using particle swarm optimization with a new evolutionary strategy based on the compromise solution of the Pareto-front. This model optimizes the most important decisions that affect a given project including: time, cost, resources, and cash flow. The study assumes each activity has different execution methods accompanied by different time, cost, cost distribution pattern, and multiple resource utilization schemes.

Applying the developed model to schedule a real-life case study project proves that the proposed model is valid in modeling real-life construction projects and gives important results for schedulers and project managers. The proposed model is expected to help construction managers and decision makers in successfully completing the project on time and reduced budget by utilizing the available information and resources.

The paper presented a novel model that has four main characteristics: it produces an optimized schedule considering time, cost, resources, and cash flow simultaneously; it incorporates a powerful particle swarm optimization technique to search for the optimum schedule; it applies multi-objectives optimization rather than single-objective and it uses a unique Pareto-compromise solution to drive the fitness calculations of the evolutionary process.

This paper aims to enable the analysts of reliability and safety systems to evaluate the risk and prioritize failure modes ideally to prefer measures for reducing the risk of undesired events.

To address the constraints considered in the conventional failure mode and effects analysis (FMEA) method for criticality assessment, the authors propose a new hybrid model combining different multi-criteria decision-making (MCDM) methods. The analytical hierarchy process (AHP) is used to construct a criticality matrix and calculate the weights of different criteria based on five criticalities: personnel, equipment, time, cost and quality. In addition, a preference ranking organization method for enrichment evaluation (PROMETHEE) method is used to improve the prioritization of the failure modes. A comparative work in which the robust data envelopment analysis (RDEA)-FMEA approach was used to evaluate the validity and effectiveness of the suggested approach and simplify the comparative analysis.

This work aims to highlight the real case study of the automotive parts industry. Using this analysis enables assessing the risk efficiently and gives an alternative ranking to that acquired by the traditional FMEA method. The obtained findings offer that combining of two multi-criteria decision approaches and integrating their outcomes allow for instilling confidence in decision-makers concerning the risk assessment and the ranking of the different failure modes.

This research gives encouraging outcomes concerning the risk assessment and failure modes ranking in order to reduce the frequency of occurrence and gravity of the undesired events by handling different forms of uncertainty and divergent judgments of experts.

The purpose of this paper is to investigate the tendency of leaders to select their followers depending on their human capital factors such as age, education level, previous working experience and training.

The participants were 1,388 employees working in a randomly selected sample of 289 small-sized businesses operating in Yemen. A self-reported questionnaire was used to collect the data. The correspondence analysis method was used to explore the tendency of leaders to select their followers depending on their human capital factors.

We found significant corresponding relationships between leadership styles and the selection of the followers' human capital factors. The passive avoidant style was found to select middle-age, long-experience and fully-trained followers. Transactional style on the other hand was found to select young, middle-level experience and non-trained followers. The transformational leadership style was found to have no selection preferences towards any of the human capital factors except for working experience.

Although, some previous studies tried to understand the leaders–followers relationships, no one investigated the tendency of leaders to select their followers according to their preferences. This study contributes significantly to the leaders–followers theory by studying the selection process of the leadership style of their followers' human capital factors. Understanding this phenomenon could help explain why some leadership styles are more effective than others, especially in very limited resources contexts such as micro-sized businesses.

While ISO 9001 standard certification is approaching saturation in developed countries, other nations are still struggling with the implementation of ISO 9001. This study provides insights into countries with a very low number of registered certifications to understand the reasons behind the limited implementations, more particularly using evidence from Yemen. The objective of the study is to assess: the awareness, understanding, motivations, barriers and the benefits of implementing ISO 9001.

A survey was conducted to measure awareness levels, understanding, driving factors, barriers and the benefits of ISO 9001. Data collection was carried out through the classification of targeted firms into two separate categories, certified and noncertified organizations. The classification of firms was conducted to enrich the understanding from two different perspectives. A total of 72 responses, from companies ranging in size from large to small, and in both the private and public sectors, were analyzed using the descriptive and multiple correspondence analysis (MCA).

The data analysis showed that the limited implementation of ISO 9001 certifications could be due to several internal and external factors such as the relatively low awareness level of the certification and guidelines, and the inconsistency of understanding the certification purpose. The benefits focused solely on improving the quality of systems efficiency and increasing quality awareness, and not on internationalization.

The findings of this work provide the groundwork for decision-makers to understand the drivers and challenges of ISO 9001 to plan corrective actions and contribute to promote and increase the number of certified organizations in similar countries and economies. While the data in this study were collected in the context of one country, the methodology and framework used in this study can be utilized by other researchers to collect data in similar countries with a low number of ISO 9001 certifications.

This research is one of the very few that addresses the limited implementation of ISO 9001 in the Middle East and North Africa region and Yemen in particular.

This paper aims to enable the analysts of reliability and safety system to assess the criticality and prioritize failure modes perfectly to prefer actions for controlling the risks of undesirable scenarios.

To resolve the challenge of uncertainty and ambiguous related to the parameters, frequency, non-detection and severity considered in the traditional approach failure mode effect and criticality analysis (FMECA) for risk evaluation, the authors used fuzzy logic where these parameters are shown as members of a fuzzy set, which fuzzified by using appropriate membership functions. The adaptive neuro-fuzzy inference system process is suggested as a dynamic, intelligently chosen model to ameliorate and validate the results obtained by the fuzzy inference system and effectively predict the criticality evaluation of failure modes. A new hybrid model is proposed that combines the grey relational approach and fuzzy analytic hierarchy process to improve the exploitation of the FMECA conventional method.

This research project aims to reflect the real case study of the gas turbine system. Using this analysis allows evaluating the criticality effectively and provides an alternate prioritizing to that obtained by the conventional method. The obtained results show that the integration of two multi-criteria decision methods and incorporating their results enable to instill confidence in decision-makers regarding the criticality prioritizations of failure modes and the shortcoming concerning the lack of established rules of inference system which necessitate a lot of experience and shows the weightage or importance to the three parameters severity, detection and frequency, which are considered to have equal importance in the traditional method.

This paper is providing encouraging results regarding the risk evaluation and prioritizing failures mode and decision-makers guidance to refine the relevance of decision-making to reduce the probability of occurrence and the severity of the undesirable scenarios with handling different forms of ambiguity, uncertainty and divergent judgments of experts.

The purpose of this paper is to discover the most important productivity determinants of Yemeni microfinance institutions. In addition, this study tests the most appropriate tool to measure productivity in such unique industry.

The authors applied data envelopment analysis (DEA) with the variable return to scale after testing the technology return to scale assumption. Then, they used DEA with bootstrapping technique to overcome the borne biasness in the conventional DEA analysis. Finally, the authors presented the Hicks–Moorsteen (total factor productivity [TFP]) as the most suitable tool for the technology presented in this study.

In this paper, the authors found a prolonged deterioration in the productivity scores of microfinance institutions in Yemen. This study highlights the importance of operating in rural areas to improve micro finance institutions’ (MFIs’) productivity. In contrast, they found no significant differences in productivity, neither between microfinance banks and non-governmental organizations nor between Islamic and non-Islamic MFIs.

This study extends previous research in the area of productivity and its determinants. It also adds to the body of productivity knowledge and methodology within the context of the microfinance industry in Yemen.

The study discovered new productivity determinants and re-assessed the importance of some already known ones. These determinants have been studied for the first time in Yemen’s microfinance industry and have contributed to answer the question of what is the most suitable productivity method that should be used. This study proved that the Hicks–Moorsteen TFP and the variable return to scale assumption are the only suitable methods to study productivity in the microfinance industry.

The purpose of this paper is to assess the TQM readiness level of Yemeni Organizations. In addition, this study compares the level of readiness between the various Yemeni organizations.

Based on the TQM literature, related and relevant information had been gathered to develop an assessment tool used in this research. The main content of the assessment focused on statements related to the most common TQM principles. Data were collected by an assessment team and analyzed using quantitative methods to answer the related research questions.

The analysis results showed some of the TQM principles were being practiced by Yemeni organizations, to some extent, and with variant levels. The most widely practiced principle was customer focus, and the lowest principle practiced was continuous improvement. Also, the data showed the level of TQM readiness in Yemeni organizations was 58.93 percent. This level of TQM readiness indicates there is a potential for successful adoption of quality management standards and models in Yemeni organizations.

This study extends previous limited research in TQM readiness level measurement. It also adds to the body of TQM knowledge within the context of Yemen. In addition, this study contributes to the understanding of TQM implementation in an least developed countries (LDC) environment, where LDC organizational culture has its particularities on implementing TQM.

This paper contributes to a better understanding of TQM in an LDC country, which is Yemen. The paper points out which of the TQM principles are important to potential adoption of quality management standards and models. This study could further expand research, regarding the TQM in Yemen.