Fuzzy MCDM Model for Selection of Infectious Waste Management Contractors

Healthcare supply chains are under pressure to drive down costs because of digital business,shifting customer needs and new competition.Medical waste generated from medical facilities includes medical activities and daily-life activities of patients and their family members.According to statistics of the Department of Health EnvironmentalManagement,Vietnam currently has more than 13,500 medical facilities,including hospitals from central to provincial and district levels and private hospitals and medical facilities.Preventive medicine generates about 590 tons of medical waste/day and is estimated to be about 800 tons/day.Medical waste includes ordinary medical waste and hazardous medical waste;in which ordinary medical waste accounts for about 80%–90%,only about 10%–20%is hazardous medical waste including infectious waste and non-infectious hazardous waste.This is an environmental and occupational health issue that needs attention in developing countries like Vietnam.Handling large amounts of medical waste to ensure environmental and personal hygiene,doing so inefficiently creates potential hazards to the environment and increases operating costs.However,hospitals lack objective criteria and methods to evaluate and select the most optimal infectious medical waste,relying instead on their own subjective assessment and prior experience.Therefore,the author proposed a fuzzy multicriteria decision making(MCDM)model including Fuzzy Analytic hierarchy process(FAHP)and the Weighted Aggregated Sum-Product Assessment(WASPAS)for infectious medical waste contractors’selection in this research.The proposed Fuzzy MCDM method is in-tended to provide a more efficient,accurate method in the selection of infectious medical waste contractors than subjective assessment methods,thus reduce potential risks to hospitals.The results of this study can be applied to evaluate and select contractors in other industries.

Distinguished Representation of Criteria Based on Trapezoidal Fuzzy Numbers and Fuzzy Memberships in Selection of Contractors

More attention has been drawn to the selection of contractors in recent years,but little research has been conducted on distinguishing representation of performance values for qualitative and quantitative criteria in one decision-making(DM) problem yet.Thus a novel method based on fuzzy number is proposed to solve the representation issue,in which linguistic terms and fuzzy memberships are used to separately describe qualitative and quantitative criteria,and then the linguistic terms are translated into fuzzy numbers which will be defuzzified and unified with fuzzy memberships.The novel method is used to develop a synthetic decision model for selection of contractors.The model is developed to verify the feasibility of the novel method,which(1) builds a twolevel criteria system based on survey and literature summary;(2)utilizes the analytic network process(ANP) to determine criteria weights;(3) uses the novel method to make different representations of performance values for qualitative and quantitative criteria in one DM problem and then unifies different representations for decision matrices;(4) utilizes three multi-criteria decision-making(MCDM) methods containing simple additive weighting(SAW),technique for order preference by similarity to ideal solution(TOPSIS) and complex proportional assessment(COPRAS) to deal with decision matrices.Besides,a case of contractor selection is given to check the novel method by applying developed model,and the case results show that the novel method can suitably solve the representation issue of the performance values for two types of criteria as well as simplify the processes of TOPSIS and COPRAS.

Evaluating Contractors’ Safety Record and Its Influence on Performance of Road Infrastructural Projects

A number of studies conducted in Kenya and internationally indicated that most of the construction firms and contractors do not seem to strictly observe safety administration in construction industry, hence compromised performance at implementation stage of projects and even later in the post implementation or post-delivery stage. The study aimed to examine the influence of contractors’ safety record on road performance. This is to create better understanding of how the safety record of contractors could either positively or negatively influence performance of roads during post-delivery stage. The study used both descriptive survey research design and correlation design based on a pragmatic mixed method approach. Through stratified sampling and proportionate sampling, a sample of 210 was drawn from a population of 460 comprising of registered contractors and Public Service Vehicles (PSV) drivers within Nairobi County in Kenya. Questionnaires were distributed using simple random sampling. The questionnaires returned were 153 in total representing 72.8% of all questionnaires distributed to the respondents. Data was descriptively analyzed using percentages, frequencies, means and standard deviations for measuring central tendency and variability. Inferential analysis was done by use of correlation and regression. The descriptive analysis revealed that safety policy management system, insurance policy, and adequacy of standards in addressing safety outcome are to some extent practiced and adhered to. However, compliance behavior to safety procedures is still weak and requires improvement. The null hypothesis was tested and the results obtained from a simple linear regression indicated that, R = 0.657, R2 = 0.431, B = 0.359, t = 10.703, F (1,151) = 114.558, p = 0.000 < 0.05. This means that contractors’ safety record has a strong positive and significant relationship with road performance and that 43.1% of variation in performance is explained by safety record. This study recommends that contractors’ safety record should be part, and parcel of the evaluation criteria used in selection of a suitable road contractor to ensure road performance is achieved even after construction is completed. The study is significant in that it contributes to the body of knowledge by providing empirical data on the need for safety procedures in urban road construction and beyond.

Investigating Challenges in Financing Contractors for Public Sector Projects in Ghana

Contractors working with the Public sector encounter numerous challenges in financing projects in Ghana. The challenges which have persisted over the years are both financial and managerial. This paper seeks to ascertain the extent to which contractors’ challenges in acquiring funds to execute public sector projects have been solved. The study involved both qualitative and quantitative methods to ascertain the various strategies the contractors go through to obtain public sector projects focusing on the challenges associated with the project execution. The study revealed that delayed payments and inadequate cash flow on the part of government, lack of credit worthiness and inadequate collateral security from contractors are key determinants to challenges associated with financing public sector projects in Ghana. This paper recommends the establishment of a Construction Development Authority (CDA), within the Ministry of Works and Housing to develop financial plans, policies and laws for this important sector of the economy.

Some Thoughts on the Regulation of VIP Room Contractors in Macao

This article gives a brief introduction of Macao’s VIP room contractors.With the rapid expansion of the gaming industry,it appears that,among the players involved in the VIP business segment,the share percentage of gross gaming revenue to the VIP room contractors has dropped considerably and this has raised the concern for the financial stability of VIP room contractors.It appears that Macao’s regulation of VIP room contractors falls heavily on gaming licensees which sell chips to them.Although gaming licensees can get the monthly sales volume of the VIP room contractors,they may not know clearly the internal operations of the contractors. Based upon this,additional information from the VIP room contractors would be beneficial to the contractors in their credit decisions and risk management,to the regulatory authority in its continuous assessment of the financial stability of the contractors,and to the industry to better meet the requirements of other gaming jurisdictions for sustainable development of the industry.

Prediction of Client Support on Contractor Performance as a Critical Success Factor

The aim of this study was to assess the influence of client support on performance of contractors within the road construction industry in Kenya. The study adopted descriptive survey research design and correlation research design. The target population was 156 selected from road contractors, engineers working in road authorities, technical auditors and consultants in the road sector. Stratified and proportionate sampling techniques were employed in coming up with a sample size of 62 respondents drawn from a target population of 156. From the simple linear regression conducted, the findings revealed that client support influences the performance of contractors in the road construction sector. Thus, we recommend that client support is highly needed to avoid issues such as delayed payment that would adversely affect performance of contractors in the road construction industry. This will subsequently lead to timely completion of roads, achieving cost effective and quality road projects.

Factors Inhibiting the Use of Bamboo in Building Construction in Ghana: Perceptions of Construction Professionals

There is a growing concern of the integration of bamboo as a material into the building construction industry even though its potential is underscored. Certain factors serve as barriers to the use of bamboo in building construction. This study employed a questionnaire survey which sought to investigate the perceptions of 84 Architects and 100 Senior Managers of small and medium scale Building construction firms on the factors that influence the use of bamboo in building construction. Relative Importance Index and Chi-squared tests were performed to identify the significant factors that influence the use of bamboo in building construction. The results showed that the building contractors considered nonspecification of bamboo for building projects by Architects, inadequate bamboo processing companies in Ghana and insufficient cooperation from government to be the key factors which influence the use of bamboo for building construction. The results further showed that the Architects considered lack of knowledge in bamboo detailing, limited knowledge of bamboo and lack of expertise to use it, and inadequate bamboo processing companies to be the key influential factors inhibiting the use of bamboo in building construction. The results are of value to the construction industry as it identifies significant factors which influence the usage of bamboo in building construction. Promotion of bamboo usage in building construction should be given the needed publicity to create the awareness of its potential as a building material.

Contractor Monitoring and Performance of Road Infrastructure Projects in Uganda: A Management Model

An understanding of the influence of contractor monitoring on performance of road infrastructural projects in Uganda provided an impetus for this study. The objectives of the study were to: assess the relationship between contractors monitoring and performance of national road infrastructure projects and the relationship between contractor monitoring components and performance of national road infrastructure projects in Uganda. Purposive sampling was employed in selecting the procurement professionals, engineers and simple random sampling was adopted in selecting private consultants, members of parliament and respondents from the civil society organizations. Data for this study were collected using a closed ended questionnaire and interviews. Some of the major finding from this study include: weak procurement rules which lead to awarding road projects to incompetent contractors;contractor monitoring being handled by unqualified, incompetent and inexperienced professionals;lack of contractors and contract supervisors appraisal system;delay of contractors payments which affects timelines in services delivery;lack of a strong internal project monitoring and evaluation mechanism at the Uganda National Roads Agency (UNRA). The research therefore recommends the establishment of an Independent Public Infrastructure Development and Monitoring Unit by government and adoption of systems that appraise both contractors and contract supervisors with clear disciplinary actions for unsatisfactory performance by the UNRA.

Evaluation of Lead Exposure by Hand Wipes: A Review of the Effectiveness of Personal Hygiene on Industrial Sites

To evaluate the effectiveness of personal hygiene (handwashing) amongst workers at industrial sites to remove lead from their hands, a retrospective analysis of hand wipe samples was conducted using data collected by two contractors from two bridge painting projects for total lead using method ASTM E-1979-17/EPA SW846 7000B. Exposures resulted from the removal of lead-based paint from the structure and trace elements of lead found in the abrasive blast media. In total, six work tasks were evaluated and sixty unique hand wipe samples were evaluated. Thirty samples were collected during the worker’s lunch break, after they had reportedly washed their hands with a further 30 collected at the end of the workday following the same protocol. To be included in this evaluation, the contractors were required to follow NIOSH Method 9105 (Lead in Dust Wipes-Dermal Surfaces) with subsequent analysis of samples for total lead by an American Industrial Hygiene Association (AIHA) accredited laboratory. All 60 samples contained detectable lead. The lead exposures ranged from 19.5 μg to 3420 μg. The geometric mean for the samples collected was 337 μg. These results indicate that current personal hygiene practices at the evaluated sites are not effective at removing lead from worker’s hands during and after the workday. They also suggest that the residual lead measured on the workers’ hands, at the end of the shift, is likely contributing to the elevated blood lead levels in this population.

Application of the PKPM-BIM construction management platform in project security management

This paper introduces the PKPM-BIM construction management platform and its applications in the construction security management. The PKPM-BIM platform is an integrated management system mainly developed for the contractors to implement the BIM-aided construction management. Application of BIM technology would bring many beneficial changes to the security management in construction.

Estimating harvest costs and projecting quantities of logging residues for small-scale forestry in Nasushiobara, Tochigi Prefecture, Japan

We used GIS on a regional scale to estimate and compare supply potentials and costs of small-scale logging systems, a mini-forwarder and a 4-ton truck operated by private logging contractors, and manual logging and a light truck operated by individual forest own- ers, with the mechanized operational system of the Forest Owners＇ Asso- ciation. Total potential yields of timber and logging residues were esti- mated as 418,895 m3 and 254,962 m3, respectively. The economic bal- ances were estimated and available amounts were projected as supply potentials from profitable sub-compartments. As a result, available amounts of timber and logging residues were estimated at 375,466 m3 （89.9%） and 203,850 m3 （80.0%）, respectively. Because their transport expenses were lower than for other systems the most profitable sub-compartments were operated by private logging contractors who sold logging residues at a plant. The profitable sub-compartments operated by individual forest owners were few because the extracting distances were usually greater than 20 m. Raising logging residue prices from 3,000 yen·m-3 to 4,080 yen·m-3 or 6,800 yen·m-3, and establishing forest roads, which reduced some extracting distances to less than 20 m, increased the number and area of profitable sub＊compartments, and increased available amounts of logging residues.

Synthetic Evaluation of Contractor's Performance in Outcome-Based Contract

Outcome-based contract( OBC) is a kind of contracting mechanism,which allows the customer to pay only when the firm has delivered outcomes,rather than activities and tasks involved. To achieve the higher demand of the delivering outcome of the contract,the evaluation of contractor's performance was focused on. A reasonable and objective contractor performance evaluation system is constructed by considering various uncertainties. The set pair theory is used to analyze the four-element connection of quality of service contractors. It aims to provide a theoretical basis for the decisionmaker to make confirmation of the equipment contractor who has a better performance and development trend.

A NOTE ON PROBABILISTIC CONTRACTOR COUPLE AND SOLUTIONS FOR A SYSTEM OF NONLINEAR EQUATIONS IN N A MENGER PN-SPACES

The concept of (Phi, Delta)-type probabilistic contractor couple was introduced which simplifies and weakens the definition of probabilistic contractor couple given by Zhang Shisheng. The existence and uniqueness of the solutions for a system of nonlinear operator equations with this kind of propabilistic contractor couple in N. A. Menger PN-spaces were studied. The works improve and extend the corresponding results by M. Altman, A. C. Lee, W. J. Padgett et al.

（Φ，△）－TYPE PROBABILISTIC CONTRACTOR AND SOLUTIONS FOR A NONLINEAR OPERATOR EQUATIONS IN MENGER PN－SPACES

The purpose of this paper is to introduce the coneept of (Φ,△)-type probabilistic contractor in Menger PN-spaces and to study the existence and uniqueness of solutions for the nonlinear operator equations with such probabilistic contractor in Menger PN-spaces.The results presented in this paper improve and extend the corresponding results in [1] and [4-8].

Contractor Selection Criteria in Ghanaian Construction Industry: Benefits and Challenges

Selecting a contractor for construction project is a difficult decision to be taken by a client because it may lead to construction delivery problems or successful delivery of the project. This study, therefore, investigated the contractor selection criteria in the Ghanaian construction industry, considering the benefits and challenges. A quantitative research method was adopted in this study through the use of a questionnaire. The target population for the study consisted of registered contractors and consultants in the Ashanti and Brong-Ahafo regions of Ghana. It was found that though the construction professionals are well vested with the prequalification selection criteria that are being used within the Ghanaian construction industry, they were not familiar with multi-criterial section methods. It was also found that the benefits of the contractor selection criteria include: enabling the client to select contractors who are performers for the project, saving the project owner a lot of time, minimizing the possibility of contractor default, and facilitating the achievement of project success and the objectives within the scheduled time. Furthermore, excessive cost and time overrun, poor quality standard, imprecise assessments due to lack of information, criteria being very complex and difficult to apply in practice, among others were identified as the challenges to the contractor selection criteria in Ghanaian construction industry. The study recommends for further studies to determine the impact of the identified challenges on construction projects, and ways to minimize the challenges.

Approximate Controllability of Fractional Order Retarded Semilinear Control Systems

In this paper, approximate controllability of fractional order retarded semilinear systems is studied when the nonlinear term satisfies the newly formulated bounded integral contractor-type conditions. We have shown the existence and uniqueness of the mild solution for the fractional order retarded semilinear systems using an iterative procedure approach. Finally, we obtain the approximate controllability results of the system under simple condition.

A Standard Framework for Effective Progress Reports in the State of Kuwait

The construction industry in the State of Kuwait has recently witnessed a rapid growth as the volume of construction projects increased significantly over the past decade. Because of the progress and growth of the industry and the size of the projects, the volume of disputes between the parties to the various contracts has increased accordingly. As projects become larger and more complex, their management and control become more difficult, especially in the absence of effective standard systems to for managing project progress and determining the delay, if any. Even the simple issues, as well as the large ones, if neglected and unaddressed in a timely manner, can cause huge problems that concerns to all project parties. Irrespective of addressing and managing construction delays legally, the resulting legal disputes always have other negative effects on the contracting parties. If the parties to the contract have an insight that enables them to forecast and identify the issues that may cause a conflict before it occurs, that eliminates a myriad of problems before they occur, and greatly reduces the chances of further conflict between contracting parties. This paper presents a framework for a novel progress reporting system that can help minimize contract disputes in the state of Kuwait.

Impact of Procurement Methods and Procurement Requirements on Cost Over-run of Public Building Projects in Uganda

Cost over-run in building projects is endemic and routinely increases construction cost to as high as 52%of contract sums in Uganda.The consequence of this is underachievement of investment objectives due to additional costs to complete projects.This research investigated how procurement requirements and procurement methods combine to determine cost over-run of building projects.Procurement requirements of bid time,performance bond,insurance,workload and experience of contractors were investigated within contexts of procurement methods of open domestic bidding,restricted domestic bidding,open international bidding,restricted international bidding and requests for quotations.Purposive and snow-ball sampling were used in identifying construction professionals,consultants and contractors of building projects with cost over-runs.Correlation and independence of procurement requirements on 37 cost over-run datasets were analysed by Spearman's bivariate correlation co-efficient at 5%level of significance and variable inflationary factor of less than 5 respectively.Bid time and performance bond were found to reduce cost over-run of building projects most followed by workload and experience.Insurance increased cost over-run marginally.The novel contribution of this research is a model that explains 63%of cost over-run with 9%margin of error.The variants of the model for each procurement method are presented.

A Maturing Seismic Contractor in the International Market

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Not really an aftermath.The role of actual construction in the design process of the Sydney Opera House roof

For the past 50 years,the Sydney Opera House has been the subject of a prodigious hagiography of the personalities involved in its realization and their legendary querelles.Yet it remains paradoxically unexplored when it comes to its operative construction decisions,particularly those that relate to the erection of its renowned superstructure.Through the analysis of a newly discovered set of shop drawings prepared for the innovative formwork system of the iconic roof sails,the paper contributes to the construction history of the building whilst shedding light on the hitherto unacknowledged role of the general contractor in the design process.In doing so,it questions the validity of conventional assumptions about the technical division of labour in complex projects,where construction and project management tend to be kept separate from architectural and structural design,furthermore suggesting the need for broader design exegeses,combining project-based and production-based concerns.In reflecting on its import for contemporary practice,the study suggests that the revealing picture of the Sydney Opera House project,as it emerged from the cumbersome archive-based crossanalysis of the manual documentation produced for it,is in principle much easier and perhaps important to obtain today.This is due,on the one side,to availability and diffusion of digital project collaborative platforms;on the other side,to the merging and the blurring of professional and non-professional design contributions.