scholarly journals Risk Evaluation of Sewage Treatment PPPABS Projects Using Combination Weight Method and D-S Evidence Theory

Complexity ◽  
2020 ◽  
Vol 2020 ◽  
pp. 1-12
Author(s):  
Hui Zhao ◽  
Zehui Bu ◽  
Shengbin Ma

In order to make up for the shortage of public-private partnership (PPP) model, more and more sewage treatment PPP projects have adopted the asset-backed securitization (ABS) model. To ensure success of sewage treatment PPPABS projects, risk evaluation, which has remained scarcity and unscientific, is becoming an urgent problem to be solved. Firstly, this paper identifies critical risk factors by literature analysis and expert interview. The final risk system is established from the perspectives of macrorisks, basic asset risks, transaction structure risks, operational risks, and other risks, which include 17 second risk factors. Then, the overall risk evaluation method is proposed based on combination weight method and Dempster–Shafer (D-S) evidence theory. Next, Beijing capital Co. Ltd. sewage treatment PPPABS project as a case is employed to verify the feasibility and effectiveness of the proposed method. Finally, awareness of existing risks, suggestions from law risk, quality risk, underwriting and issue risk, and credit enhancement are provided for sewage treatment PPPABS projects. All above studies are expected to provide helpful references for evaluating overall risk of sewage treatment PPPABS projects.

2020 ◽  
Vol 2020 ◽  
pp. 1-16
Author(s):  
Hui Zhao ◽  
Shengbin Ma ◽  
Zehui Bu

Construction of sponge city PPP projects is perceived as a feasible measure for achieving the sustainable urbanization. To ensure the success of sponge city PPP projects, reasonable sharing of risks among participants, which has remained scarce and unscientific, is becoming an urgent problem to be solved. In order to enable the individual participant to accurately grasp the situation of his own risks, specifically for the individual participant, this paper constructs a risk-sharing framework for sponge city PPP projects. Firstly, this paper identifies critical risk factors by the Delphi method. The final risk evaluation index system is established from the perspectives of political risks, economic risks, construction risks, and operational risks, which include 16 secondary risk factors. Then, risk factors’ weights are determined based on a combination weight method (combining the G1 method and the C-OWA operator). Next, in order to share risks reasonably, the first step is to obtain the risk factors that can be borne by one participant and define the risk factors that need to be shared among participants through the method of combining GCA method and TOPSIS method. The second step is to build a model based on the utility theory to determine the proportion of risks shared among participants. Finally, the sponge city PPP project in Qingshan demonstration area of Wuhan city as an example is employed to verify the feasibility and effectiveness of the constructed risk-sharing framework. All the aforementioned studies are expected to provide helpful references for reasonable risk sharing in sponge city PPP projects.


2021 ◽  
pp. 1-11
Author(s):  
Fu Shuai ◽  
Sheng Kai ◽  
Si Qingmin ◽  
Guo Xinyao ◽  
Wang Feiyin

Fatigue failure issues of runway at airports have become one of core tasks in airport safety management. How to recognize fatigue failure risk factors of concrete runways at airports and implement a quantitative assessment on failure risks of runways is a key topic that is studied in the industrial circle and academic circle at present. For this reason, an integral analysis on internal and external causes of fatigue failure of runways was carried out, which recognized and extracted 18 risk factors. Evaluation values of quantitative risk factors were calculated through a threshold method and evaluation values of qualitative factors were determined by expert scoring. Subsequently, weights of all risk factors were given by G1 method. Finally, the comprehensive risk evaluation value of concrete runways was gained through layer-by-layer coupling. A case study was carried out in the A airport. Results show that the calculated comprehensive risk evaluation value of fatigue failure of concrete runways at airports by the proposed method is basically consistent with engineering objective practical value. The proposed method is expected to be applicable in other airports. The comprehensive risk evaluation value of the concrete runway failure at A airport is 0.49, indicating certain risks of fatigue failure. It is necessary to adopt engineering and management measures according to risk factors with large evaluation values to control the fatigue failure risks. This study concludes that the proposed fatigue failure risk index system of concrete runway of airports is scientific and effective. Moreover, the proposed risk evaluation method is feasible and it provides a new idea and method to fatigue failure risk evaluation of concrete runways at airports.


Author(s):  
Guo-Niu Zhu ◽  
Jie Hu ◽  
Jin Qi ◽  
Tao He ◽  
Ying-Hong Peng

AbstractChange mode and effects analysis (CMEA) is a powerful technique for measuring product flexibility toward future changes and diminishing the cost of redesign as well as shortening time to market. As a systematic methodology, it provides an in-depth view for the investigation of potential changes, causes, and effects in designs, products, and processes. Traditional CMEA determines the risk priorities of change modes by using change potential number, which requires the risk factors of design flexibility, occurrence, and readiness to be precisely evaluated. However, this is not always possible in real applications due to the uncertainty and subjectivity involved in the early design stages. It has been criticized much for its deficiencies in criteria weighting of the risk factors, change potential number calculation, and risk priorities determination of the change modes. This paper presents a systematic evaluation approach for determining a more rational rank of change modes by combining with the entropy weight method, rough number, and grey relational analysis. In this study, the entropy weight method is adopted to calculate the relative importance of risk factors. Rough number is presented to aggregate individual weights and preferences, and to manipulate the vagueness in the evaluation process. Then a rough number enhanced grey relational analysis is proposed to evaluate the risk ranking of change modes. Finally, a practical example is put forward to validate the performance of the proposed method. The result shows that the proposed change mode evaluation method can effectively overcome the shortcomings of traditional CMEA and strengthen the objectivity of product flexibility measurement.


2011 ◽  
Vol 368-373 ◽  
pp. 2216-2219
Author(s):  
Wei Zhang ◽  
Leng Fei Sun

Engineering projects often face risks from technology, economy, nature, social and other aspects. Risk factors are of interdependence and interaction, so they are very difficult to be quantified. The paper describes a risk evaluation method for engineering projects based on fuzzy set theory which uses respective fuzzy numbers to evaluate the factors. The primary weights of factors and evaluation of alternatives are determined by applying fuzzy numbers. The results are consistent with the results calculated by conventional risk evaluation method. The research demonstrates that the method is objective and accurate, and is of an application value in the risk evaluation for engineering projects.


Author(s):  
Jin Han ◽  
Jing Zhan ◽  
Xiaoqing Xia ◽  
Xue Fan

Background: Currently, Cloud Service Provider (CSP) or third party usually proposes principles and methods for cloud security risk evaluation, while cloud users have no choice but accept them. However, since cloud users and cloud service providers have conflicts of interests, cloud users may not trust the results of security evaluation performed by the CSP. Also, different cloud users may have different security risk preferences, which makes it difficult for third party to consider all users' needs during evaluation. In addition, current security evaluation indexes for cloud are too impractical to test (e.g., indexes like interoperability, transparency, portability are not easy to be evaluated). Methods: To solve the above problems, this paper proposes a practical cloud security risk evaluation method of decision-making based on conflicting roles by using the Analytic Hierarchy Process (AHP) with Aggregation of Individual priorities (AIP). Results: Not only can our method bring forward a new index system based on risk source for cloud security and corresponding practical testing methods, but also can obtain the evaluation result with the risk preferences of conflicting roles, namely CSP and cloud users, which can lay a foundation for improving mutual trusts between the CSP and cloud users. The experiments show that the method can effectively assess the security risk of cloud platforms and in the case where the number of clouds increased by 100% and 200%, the evaluation time using our methodology increased by only by 12% and 30%. Conclusion: Our method can achieve consistent decision based on conflicting roles, high scalability and practicability for cloud security risk evaluation.


Author(s):  
Quanle Zou ◽  
Tiancheng Zhang ◽  
Wei Liu

In recent years, various large- and medium-sized shopping malls have been essential components of each city with the speed-up of China’s urbanization process and the improvement of residents’ living standard. A method for evaluating fire risk in shopping malls based on quantified safety checklist and structure entropy weight method was proposed according to related literatures as well as laws and regulations by analyzing the characteristics of fires occurring in shopping malls in recent years. At first, the factors influencing the fire risk in shopping malls were determined by carrying out on-site survey and visiting related organizations to construct an evaluation index system for fires occurring in shopping malls; afterwards, a quantified safety checklist composed of four parts (i.e. safety grade, grade description, scoring criterion and index quantification) was established based on related laws and regulations; subsequently, index weights were determined by utilizing structure entropy weight method, thus putting forward a method for assessing fire risk in shopping malls based on quantified safety checklist and structure entropy weight method. Eventually, the applicability of the evaluation method was validated exampled by Wal-Mart. The research result provides a theoretical basis for further improvement of the theoretical system for fire risk evaluation in shopping malls, and also exerts practical and guidance significance on timeous and effective early warning as well as prevention and control of building fires.


1981 ◽  
Author(s):  
W B Kannel

Coronary heart disease is a common, highly lethal, disease which frequently attacks without warning and too often presents with sudden death as the first symptom. Chances of an American male developing CHD before age 60 are one in five.Most angina, infarctions and sudden deaths represent medical failures which should have been forecasted and prevented. About 30% of first MI's will shortly develop angina and experience a per annum death rate, half of which will be sudden deaths. Reinfarctions will occur at 6% per year and half the recurrences will be fatal.No major innovations are needed to identify coronary candidates or to establish their risk from the joint effect of known risk factors. However, all have much to learn about motivating changes in behavior required to control the major risk factors such as cigarette smoking, faulty diet, overweight, sedentary living, abnormal lipids, hypertension and impaired glucose tolerance.Low density lipoprotein cholesterol promotes atherogenesis whereas HDL-cholesterol is protective, and the net effect is judged by their ratio. Hypertension, systolic or diastolic, labile or fixed, at any age in either sex is a powerful contributor to CHD. The impact of diabetes is greater for women, diminishes with age and varies depending on coexisting risk factors.Optimal risk evaluation requires quantitative combination of risk factors so as to include persons with multiple marginal risk factor abnormalities who are at high risk.


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