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This paper reports a study carried out to compare the attitudes and perceptions of Hong Kong construction contractors and owners on the importance of various construction risks and also how the risks should be allocated between the parties to the contract. Data were collected by a questionnaire survey on industry professionals representing contractors and owners. Both the owners and the contractors have attached high importance to risk factors such as safety, quality and financial failures. Results also indicate a readiness on the part of the contractors to allocate a greater portion of risks to themselves.

To obtain a general opinion concerning the implementation of quality management systems (QMS) of construction‐related firms in the USA and Hong Kong, and to determine whether construction‐related firms have ever made an effort to measure quality improvement.

Two questionnaire surveys, one in the USA and one in Hong Kong, were conducted by sending out questionnaires to construction‐related companies. The surveys were then followed by 15 in‐depth, semi‐structured interviews with top management and quality managers of construction‐related firms in both the USA and Hong Kong.

The results of the study indicate that different perceptions towards the implementation of formal quality management systems existed between the two places. Mainly due to the lack of initiative and promotion from both clients and governments, construction companies in the USA have failed to see the need to obtain the ISO 9000 certification. In Hong Kong, however, the government's initiatives have resulted in a high percentage of companies having certified to the ISO 9000 standards. The results of the study also indicate that, though most companies used different tools for quality measurements, such measurements were mainly for monitoring and for recording purposes.

This is the first time that such a rigorous comparative study of quality management systems in the construction companies of two different countries has been conducted. It provides useful and practical insights into the differences and similarities between US and Hong Kong construction industries. This paper should be extremely valuable to practitioners in both countries, particularly the USA.

The purpose of this paper is to examine how effectively the cost appraisal system proposed measures the cost of poor quality (COPQ) in a construction project. The paper first formulates how COPQ can be measured and later clarifies the relationship between COPQ, labor productivity, and profitability.

In order to measure COPQ, the researchers prepared data entry forms for recording COPQ items on a daily basis and formulated the cost contribution of lost material, lost man-hours, lost machinery hours, and lost overhead on the overall COPQ for the project. The proposed method was then applied in a case study.

The results showed that, for the 60-days study period, COPQ decreased by about 24 percent while labor productivity and profitability increased by about 17 and 11 percent, respectively, after the implementation of COPQ measuring system. This study further supports the use of the COPQ system in construction projects as a mechanism to facilitate continuous improvement.

COPQ is a major cost that is often ignored in construction projects due to the difficulty of measuring it. This paper presents a COPQ measuring and recording system capable of identifying COPQ. The implementation of the system is shown to increase productivity and profitability as demonstrated by the project used for the case study.

This study attempts to examine how employee orientations and paranoid arousal intersect and influence the voice behaviors of employees, as they significantly influence workplace practices.

Drawing on a multi-source and multi-time-based survey, the data were collected from 37 supervisors and 270 employees in 80 branches of 11 microfinance banks. SmartPLS-4.1 was used to test the measurement and structural model. A total of 307 questionnaires were used for the data analysis.

This research presents the contrasting results of employee orientations with voice behavior. Results support the direct relationship between paranoid arousal and promotive-prohibitive voice behaviors. However, no support was found for approach-avoidance orientation and promotive-prohibitive voice behaviors.

Employees' ability to voice-out in organizations depends on several motivational factors, consolidated into three areas – organizational culture, leadership, and individual traits. Organizations must implement a culture of transparency and open communication. Participative and inclusive leadership styles increase the quality of relationships with employees, stimulating a promotive voice. A support system for employees is needed to advance in their careers, increasing promotive behaviors.

The study adds value to the existing body of knowledge by studying approach-avoidance orientations and voice behaviors through the lens of paranoid arousal in the framework.

Managerial shortfalls can considerably undermine the delivery performance of construction projects. This paper appraises the project management essentials (PMEs) for successful construction project delivery.

Following a detailed literature review, a questionnaire survey was developed encompassing 20 PMEs that were identified. An opinion questionnaire survey was used to facilitate data collection from key construction stakeholders in the Malaysian construction industry. The survey data were subjected to descriptive statistics and exploratory factor analysis.

Findings indicated that the leading PMEs are competency of the project team, competency of project manager, good leadership, effective planning and control and realistic cost and time estimate. Spearman’s rank correlation tests affirmed a good agreement on the ranking of PMEs across stakeholder groups. The present study found that PMEs for construction have a total of four dimensions, namely: scope, communication and competence management; stakeholder commitment and collaborative engagement; construction time–cost planning and control; and environment, health, safety and quality management.

The findings could potentially contribute to the development of appropriate project management best practices to address managerial shortfalls in Malaysia and other developing countries.

This paper bridges the identified knowledge gap about critical managerial dimensions for successful project management in construction. The present study adds to the existing body of knowledge around this under-explored area in the construction management literature.

The purpose of this paper is to develop a decision support tool for risk-based maintenance scheduling for a large heavily equipped gas sweetening unit in a Liquefied Natural Gas (LNG) plant. Two conflicting objectives, i.e., total maintenance cost and the reliability, are considered in the tool. The tool is tested with the real plant data and suggests several Pareto-optimal schedules for a decision maker to choose from. The financial impacts are assessed.

A bi-objective scheduling optimization model is developed for maintenance scheduling using a risk-based framework. The model is developed integrating genetic algorithm and simulation-based optimization to find Pareto-optimal schedules. The model delivered true Pareto front optimal solutions for given plant-specific data. The two conflicting objectives: the minimization of total expenditures incurred on maintenance-related activities and improving the total reliability are considered.

For large and complex processing facilities such as LNG plant, a shutdown of facility generates a significant financial impact, resulting in millions of dollars in production loss. The developed risk-based equipment selection strategy helps to minimize such an event of production loss by generating a thorough maintenance strategy for inspection, repair, overhaul or replacement schedule of the unit without initiating the shutdown. The proposed model has been successfully applied to obtain an optimize maintenance schedule for a gas sweetening unit.

A future work may consider the state-dependent models for various failure modes that will result in obtaining a better representation of the model. The proposed scheduling can further be extended to multi-criteria scheduling including availability, resource limitation and inflationary condition. A comparative analysis with other meta-heuristic techniques such as harmony search algorithm, tabu search, and simulated annealing will further help in confirming the schedule obtained from this application.

Maintenance scheduling using a conventional approach for special equipment generally does not consider the conflicting objectives. This research addresses this aspect using a bi-objective model. The usefulness of risk-based method is to assist in minimizing the financial and safety risk exposure to the operating companies, but some variation in results is expected due to varying risk matrix for different organizations.

Managing two objectives, i.e., minimizing the cost of maintenance-related activities, while at the same time maximizing the overall reliability dramatically, helps in mitigating adverse safety and financial risk due to fires, explosions, fatality and excessive maintenance cost.

Research develops a decision support tool for managing conflicting objectives for an LNG process. This research highlights the impact of utilizing the simulation-based approach coupled with risk-based equipment selection for complex processing unit or plant maintenance scheduling optimization.

Lower Indus Basin (LIB) region is the food basket of Pakistan, and climatic variation in response to global warming might severely affect the crop production and, thus, food security and ultimately to the economy of the country.

The authors analyzed the previous climatic factors data series of LIB region to investigate the past and present climatic trends and to predict the future changes. Climatic changes were monitored by studying temperature, rainfall and relative humidity (RH) dynamics at two locations (Lahore and Multan) of the LIB region, Pakistan, by using data from 1953 to 2006. The data were divided into two equal halves (1953-1979 and 1980-2006) and statistically compared for the aforementioned weather parameters.

The results suggested that mean minimum temperature (MMT) and overall mean temperature in winter were significantly increased, whereas few summer months had also experienced the reduction in both temperatures. However, few minor changes were also observed for the mean maximum temperature at both locations. The rainfall amount did not vary significantly at both locations, with the exception for the months of February and June at Lahore location, which experienced relatively higher rainfall in latter period (1980-2006). However, morning and evening RH was significantly increased at Multan throughout the year and for some selected months (February-March and May-July) at Lahore. However, the comparison of climatic data of both temporal halves suggested either dryer weather during winter months because of increase in MMT and/or increase in area under irrigated agriculture, resulting in more evaporation at both locations. Similarly, the data also indicated the early monsoon rainfall patterns in summer and late western depression rainfall spell during winter, which played key role to affect the crop yield because of irregular rain events.

The current manuscript would be very useful for the disaster management authorities and agriculture sector to predict the future irregular trends of climate change in Pakistan. Moreover, current findings can be important tool toward the management of climatic changes issues (i.e. floods and dryer spells) and to formulate the future strategies for the improved crop growth in arid and/or semi-arid developing nations such as Pakistan.

The current manuscript, for the very first time, provided detailed insights into key climatic factors changes for past seven decades, into the severely climate change-affected areas of the world. Furthermore, agricultural sector is likely to be severely affected because of minor seasonal change in temperature and moisture, and have a strong food security impact, which can be reflected with current data set to cope with both ecological and economic impacts of climate change in Pakistan. The current findings would be useful to manage the climate change-related issues in Pakistan, including the social, environmental and economic.

The aim of this research is to design a robust active disturbance attenuation control (RADAC) technique combined with an extended high gain observer (EHGO) and low pass filter (LPF).

For designing a RADAC technique, the sliding mode control (SMC) method is used. Since the standard method of SMC exhibits a chattering phenomenon in the controller, a multilayer sliding mode surface is designed for avoiding the chattering. In addition, to attenuate the unwanted uncertainties and disturbances (UUDs), the techniques of EHGO and LPF are deployed. Besides acting as a patch for disturbance attenuation, the EHGO design estimates the state variables. To investigate the stability and effectiveness of the designed control algorithm, the stability analysis followed by the simulation study is presented.

The major findings include the design of a chattering-free RADAC controller based on the multilayer sliding mode surface. Furthermore, a criterion of integrating the LPF scheme within the EHGO scheme is also developed to attenuate matched and mismatched UUDs.

In practice, the quadrotor flight is opposed by different kinds of the UUDs. And, the model of the quadrotor is a highly nonlinear underactuated model. Thus, the dynamics of the quadrotor model become more complex and uncertain due to the additional UUDs. Hence, it is necessary to design a robust disturbance attenuation technique with the ability to estimate the state variables and attenuate the UUDs and also achieve the desired control objectives.

Designing control methods to attenuate the disturbances while assuming that the state variables are known is a common practice. However, investigating the uncertain plants with unknown states along with the disturbances is rarely taken in consideration for the control design. Hence, this paper presents a control algorithm to address the issues of the UUDs as well as investigate a criterion to reduce the chattering incurred in the controller due to the standard SMC algorithm.

The purpose of this study is to adopt a supply chain performance measurement (SCPM) framework as proposed by (Dweiri and Khan 2012) to model a novel SCPM index (SCPMI) system to measure and improve supply chain performance (SCP).

The adopted SCPM framework developed by Dweiri and Khan (2012) is used to model a generic SCPMI framework aided by analytic hierarchy process (AHP) method and inputs from industrial experts. To exemplify the applicability and efficiency of the generic SCPMI system, an automobile assembling company from an emerging economy was used. This SCMPI system is used to measure, improve and measure post-improvement SCP guided by DMAIC (define, measure, analyze, improve and control) methodology.

The study’s initial measurement results showed an average SCP of the case company over a four-month period as 82 per cent. DMAIC methodology was used to identify inherent problems and proposed improvements. The post-improvement SCP measurement saw an improvement from an average of 82 to 83.82 per cent over the four-month period.

The proposed generic SCPMI framework aided by AHP-DMAIC has been successfully implemented in a case company. After implementation, managers and decision-makers saw an improvement in their SCP. The proposed SCPMI system and results can be useful for benchmarking by manufacturing organizations for continuous SCP improvement.

An original SCPMI framework proposed is general in nature and can be applied in any organization.

In this research paper, an adaptive output-feedback robust active disturbance rejection control (RADRC) is designed for the multiple input multiple output (MIMO) quadrotor attitude model subject to unwanted uncertainties and disturbances (UUDs).

In order to achieve the desired control objectives in the presence of UUDs, the low pass filter (LPF) and extended high gain observer (EHGO) methods are used for the estimation of matched and mismatched UUDs, respectively. Furthermore, for solving the chattering incurred in the standard sliding mode control (SMC), a multilayer sliding mode surface is constructed. For formulating the adaptive output-feedback RADRC algorithm, the EHGO, LPF and SMC schemes are combined using the separation principle.

The findings of this research work include the design of an adaptive output-feedback RADRC with the ability to negate the UUDs as well as estimate the unknown states of the quadrotor attitude model. In addition, the chattering problem is addressed by designing a modified SMC scheme based on the multilayer sliding mode surface obtained by utilizing the estimated state variables. This sliding mode surface is also used to obtain the adaptive criteria for the switching design gain parameters involved in the SMC. Moreover, the requirement of high design gain parameters in the EHGO is solved by combining it with the LPF.

Designing the flight control techniques while assuming that the state variables are available is a common practice. In addition, to obtain robustness, the SMC technique is widely used. However, in practice, the state variables might not be available due to unknown parameters and uncertainties, as well as the chattering due to SMC reduces the performances of the actuators. Hence, in this paper, an adaptive output-feedback RADRC technique is designed to solve the problems of UUDs and chattering.