Alternative approach to credit scoring by DEA: Evaluating borrowers with respect to PFI projects

Private finance initiative (PFI), as a form of public/private partnership (PPP), helps to contract the private sector to governmental projects. In contrast to traditional public financed projects, PFI projects are procured by allowing a private sector entity to take the responsibility to design, build, finance, and operate (DBFO) an asset for a contract period of up to several decades. Moreover, banks are perceived to take the leading role in financing PFI projects. Since project financing involves credit assessment of loan applicants, banks have employed popular credit scoring models to assess their creditworthiness. Although the existing models are useful for credit scoring, new models have to emerge in response to ever-changing business practices. This paper therefore aims at introducing the application of data envelopment analysis (DEA) as an alternative credit-scoring model. Unlike traditional credit-scoring building on a formula where weights to a set of criteria are assigned subjectively, DEA will automatically generate the relative weights for analysis. However, incorporating DEA demands additional considerations, which are discussed in this paper. Finally, examples are demonstrated for illustrating this alterative approach to credit scoring by DEA.     

An interval-based possibilistic programming method for waste management with cost minimization and environmental-impact abatement under uncertainty

Considerable public concerns have been raised in the past decades since a large amount of pollutant emissions from municipal solid waste (MSW) disposal of processes pose risks on surrounding environment and human health. Moreover, in MSW management, various uncertainties exist in the related costs, impact factors and objectives, which can affect the optimization processes and the decision schemes generated. In this study, an interval-based possibilistic programming (IBPP) method is developed for planning the MSW management with minimized system cost and environmental impact under uncertainty. The developed method can deal with uncertainties expressed as interval values and fuzzy sets in the left- and right-hand sides of constraints and objective function. An interactive algorithm is provided for solving the IBPP problem, which does not lead to more complicated intermediate submodels and has a relatively low computational requirement. The developed model is applied to a case study of planning a MSW management system, where mixed integer linear programming (MILP) technique is introduced into the IBPP framework to facilitate dynamic analysis for decisions of timing, sizing and siting in terms of capacity expansion for waste-management facilities. Three cases based on different waste-management policies are examined. The results obtained indicate that inclusion of environmental impacts in the optimization model can change the traditional waste-allocation pattern merely based on the economic-oriented planning approach. The results obtained can help identify desired alternatives for managing MSW, which has advantages in providing compromised schemes under an integrated consideration of economic efficiency and environmental impact under uncertainty.     

A regulatory robust conditional approach to measuring the efficiency of wholesale water supply and wastewater treatment services

A benchmarking evaluation instrument was designed with a European Union country regulatory authority for water supply and wastewater treatment services to determine the efficient operating cost of its service providers that operated in the wholesale market segment in the 2017–2021 period. To this end, the non-parametric Data Envelopment Analysis technique was adapted to a robust and conditional approach. The results point to similar mean efficiency scores between water supply and wastewater services in the five-year period, despite the greater heterogeneity in the latter. Furthermore, the estimated potential cost savings for both services ranged from about 2% to 3%.     

Discrete time–cost–environment trade-off problem for large-scale construction systems with multiple modes under fuzzy uncertainty and its application to Jinping-II Hydroelectric Project

This paper presents a discrete time–cost–environment trade-off problem for large-scale construction systems with multiple modes under fuzzy uncertainty. A multi-objective decision making model is established in which the total project duration is regarded as a fuzzy variable. To deal with the uncertainty, the fuzzy numbers in the model are defuzzified by using an expected value operator with an optimistic–pessimistic index. The objective functions are to minimize the total project cost, project duration, crashing cost, and environmental impact. Furthermore, a fuzzy-based adaptive-hybrid genetic algorithm is developed to find feasible solutions. The one-point crossover and repairing strategy for mutations are designed to avoid infeasible solutions. Finally, the Jinping-II Hydroelectric Project is used as a practical example to demonstrate the practicality and efficiency of the model. Results and a sensitivity analysis are presented to highlight the performance of the optimization method, which proves to be very effective and efficient compared to other algorithms.     

基于深度访谈扎根分析的绿色建筑项目脆弱性与风险关系机理研究

脆弱性作为一个与风险密切相关的因素,由于其隐蔽性特性,在传统工程项目风险的研究中未得到足够的重视。因此,本文从风险管理的视角,试图对绿色建筑项目脆弱性的概念和内涵进行明确,探究绿色建筑项目脆弱性与风险的关系机理。首先运用经典扎根理论方法对访谈资料进行实质性编码,归纳和明确了项目脆弱性和风险2个核心范畴,进一步通过扎根理论的理论编码程序,构建绿色建筑项目脆弱性与风险的关系机理理论框架。整个研究运用扎根理论,通过深度访谈和案例分析,揭示脆弱性对项目风险的影响路径和机理,弥补现阶段绿色建筑项目风险研究忽略脆弱性的不足,研究成果可为绿色建筑项目风险管理提供科学依据。     

浅谈建筑工程屋面渗漏水原因分析及防治措施

建筑屋面渗漏水是建筑工程质量问题中最突出的问题之一,从设计、材料、施工三个方面阐述和分析了工程屋面渗漏水的原因,并提出了防治措施和治理办法,从而实现建筑工程屋面无渗漏的目标。     

Measuring and comparing the efficiency of water utility companies: A data envelopment analysis approach

This study provides an analysis of Italian water utilities to determine the effects on their efficiency of certain relevant variables that have been broadly discussed in the existing literature. We reviewed the annual financial statements of 43 Italian water utility companies and obtained other technical data from Co.n.vi.r.i., the Italian national authority for water. Using data envelopment analysis we assessed their cost efficiencies and, using non-parametric statistic methods, we discuss the significant differences among clusters.We found that ownership structure, size and geographical location had an impact on the performance of water utilities, although with different degrees of significance.     

A bidding decision index for construction contractors

Results from applying the model on a sample of contractors, the majority of whom were international and operating in Egypt, reinforces the credibility of the developed methodology, claim the authors.     

A fuzzy Bayesian belief network for safety assessment of oil and gas pipelines

Safety assessment of oil and gas (O&G) pipelines is necessary to prevent unwanted events that may cause catastrophic accidents and heavy financial losses. This study develops a safety assessment model for O&G pipeline failure by incorporating fuzzy logic into Bayesian belief network. Proposed fuzzy Bayesian belief network (FBBN) model explicitly represents dependencies of events, updating probabilities and representation of uncertain knowledge (such as randomness, vagueness and ignorance). The study highlights the utility of FBBN in safety analysis of O&G pipeline because of its flexible structure, allowing it to fit a wide variety of accident scenarios. The sensitivity analysis of the proposed model indicates that construction defect, overload, mechanical damage, bad installation and quality of worker are the most significant causes for the O&G pipeline failures. The research results can help owners of transmission and distribution pipeline companies and professionals to prepare preventive safety measures and allocate proper resources.     

A methodology for evaluation and classification of rock mass quality on tunnel engineering

In this paper a new methodology for evaluation and classification of rock mass quality that can be applied to rock tunneling is presented. An evaluation model based on combing the analytic hierarchy process (AHP) and the fuzzy Delphi method (FDM) for assessing the rock mass rating is the main procedure. This research treats rock mass classification as a group decision problem, and applies the fuzzy logic theory as the criterion to calculate the weighting of factors. The main advantage of this procedure is that it can effectively change the weighting of each rating parameter with the variation of geological conditions. The proposed method was evaluated and applied to the actual cases that are the two tunnels along the Second Northern Highway around Taipei area in Taiwan, namely Mu-Zha and Hsin-Tien tunnels. It was found that the determined results were in a good agreement with the original data assessed by the RMR. Results of the analyses show that it can be provided a more quantitative measure of rock mass and hence minimize judgmental bias. The proposed method should be more feasible for future tunnel construction and for suggestions of tunnel support design in the geological area of Taiwan.     

浅谈事业单位小中型项目建设管理中造价的计价与控制

事业单位基建管理中,如何做到工程造价的合理性,可从决策、设计造价编制、施工过程及结算阶段进行多方面的控制。     

A proposed methodology for analysis of ground settlements caused by tunneling, with particular reference to the “buoyancy” effect

A new analytical method is proposed in order to realistically estimate the ground settlements caused by shallow tunnel construction. In the estimation of these ground settlements with the finite element method (FEM), the weight of the ground which is removed at the tunnel excavation has a large effect on the value of the settlements, when the ground is assumed as an elastic body. Some problems related to the settlements estimated by FEM are pointed out through the elastic theory, a back analysis, and field measurement results. A new analytical method is proposed, which disregards the weight of the ground removed, at the estimation of the excavation forces acting on the tunnel boundary. The appropriateness of the method is confirmed through a comparison between the analytical and the field measurement settlements.     

谈施工方如何做好市政工程竣工结算审核工作

以太原市2008年滨河西路胜利桥立交工程竣工结算审核为例,探讨了作为一名施工方的造价员,做好市政工程竣工结算审核工作的方法,并进行了系统分析,从而为类似工程竣工结算审核提供指导。     

A methodology for energy-efficient renovation of existing residential buildings in China and case study

Energy-efficient renovation had been accepted widely as the best solution for aging residential buildings. In order to guide such real projects in China and maximize the benefits in energy, environmental and economic fields from these activities, this article developed a methodology to assist decision-makers to design energy-efficient renovation plan in the early stage of design phase, and used a case study to demonstrate how to apply it. Following it, a suitable energy-efficient renovation plan, integrating all effective and available energy-saving measures, could be put forward for the subject building, and its effects on reduction of energy consumption, CO₂ emission and cost be evaluated accurately. The results showed that from the viewpoint of reducing energy consumption and CO₂ emission, energy-efficient renovation was worth being implemented to upgrade the existing residential buildings in China, but from the economic view, governments should provide certain subsidy for such real projects and increase electricity price.     

The use of time and cost utility for construction contract award under European Union Legislation

Public Awarding Authorities around the world aim at procuring construction contracts that will achieve project completion within predefined cost, time and quality constraints.     

挣值理论在P3e／c软件中的应用探讨

对挣值理论的基本原理进行了分析,并结合道路工程项目,对项目挣值理论进行了分析与应用探讨,指出了挣值管理方法是一种很有实际意义的方法,但也有不足,最后,提出应该将挣值理论和关键路径法结合起来,并在原方法中引入质量成本变量,将三者结合起来对挣值理论进行改进,形成基于费用、进度及质量的综合控制分析方法。     

Analysis of a combined cooling, heating, and power system model under different operating strategies with input and model data uncertainty

Combined cooling, heating, and power (CCHP) system models have been used by many researchers to compare their performance with conventional systems. However, decisions based on the results of computer simulations need to take into account the uncertainty of these results to get insight into the level of confidence in the predictions. This paper presents an analysis of a CCHP system model under different operating strategies with input and model data uncertainty. However, the uncertainties that underlie the variation in input parameters such as the thermal load, natural gas prices and electricity prices are not readily available. Additionally, engine performance uncertainty can be difficult to characterize because of the nonlinearity of engine efficiency curves. This paper presents practical and novel approaches to estimating the uncertainty in these and other input parameters. A case study using a small office building located in Atlanta, GA, is described to illustrate the importance of the use of uncertainty and sensitivity analysis in CCHP system performance predictions, and how the primary energy consumption, operational cost, and carbon dioxide emissions are affected by the uncertainty associated with the model input parameters.     

基于缓冲区和挣值分析的项目成本与进度风险预警

为弥补挣值分析法不具有对项目成本与进度风险量进行测评的缺陷,在挣值分析法的基础上,提出了运用缓冲区定期监测项目成本与进度风险动态变化的定量方法。该方法定义了项目成本与时间的动态缓冲区,用于表示项目成本与工期在受控范围内的变化量,并运用蒙特卡罗仿真法获取动态缓冲区尺寸;在此基础上,结合挣值分析指标,构建了项目成本与进度风险动态预警指标,对预警指标值的范围进行划分与说明。并以某弹体分系统中尾段子系统初样研制项目为例演示了该方法的使用过程,表明该方法具有良好的有效性与可操作性。     

A city made of rooms. Revisiting the interactions between urban planning and building typology in Mario Ridolfi’s projects for Terni

ABSTRACT

Mario Ridolfi’s lifelong work in the area around the Corso del Popolo in the city of Terni has merited special attention among researchers because of its sensitiveness towards the historical surroundings, its ability to integrate town-planning and architecture and its capacity to transform the city’s skin and structure. The aim of the paper is to shed light on the origins, design strategies and translation into architecture that informed the approval of the Variante al Piano di Ricostruzione Corso del Popolo, piazza del Popolo e zone adiacenti in 1959. A comparative analysis of mainly unpublished, original sketches dating back to 1932 helps to understand the planning precedents that ultimately led to the decision to open the Corso del Popolo (1984–1932), the variations of the specific layout of this urban project from 1932 to its approval in 1959 and the unique application of planning strategies into Ridolfi’s buildings for central Terni. The study reveals the persistence of previous planning ideas that were not proposed but accepted by Ridolfi, the depiction of the ‘squared street’ as a new paradigm of open space, and the intrinsic paradoxes that informed the difficult embedding of the palazzina typology into the fragile urban fabric of the old city centre.     

基于联系期望的膨胀土和改良土胀缩性评价模型

膨胀土和石灰改良膨胀土的胀缩性评价,受分析指标不确定性的多样性和动态可变性与人类思维的局限性影响与控制,是一个极其复杂的难题。应用区间数理论与集对分析耦合方法,提出了基于联系期望概念的膨胀土和石灰改良土胀缩性评价新模型,以统一刻画区间形式胀缩性评价指标的确定性和不确定性及演化态势。实例应用及与其他方法对比分析结果表明,该模型应用于膨胀土和石灰改良膨胀土胀缩性评价是有效可行的,且能简化区间数关系的分析过程,此也为其他类似不确定性问题提供了新的参考。