Environmental Comfort Criteria: Weighting and Integration

This paper presents an integration method for evaluating environmental quality in office buildings based on a series of interviews with 50 experts in the field of environmental quality in the built environment. A structured questionnaire was completed by experts during the interviews. The categories of environmental quality considered in this evaluation include lighting comfort, acoustic comfort, thermal comfort, and acceptable indoor air quality. Each category includes a set of performance criteria. Sixty-five performance criteria covering the evaluation of environmental quality in office buildings were extracted from the interviewed experts. The development of this integration method for assessing the environmental quality of built environments is described and an illustration of its application is presented.     

Framework for Evaluating the Performance of Engineering Consultants

The evaluation of consultant’s performance is crucial to the success of a consulting assignment especially when today’s construction projects are becoming more sophisticated, large-scale, and risky. However, since individual clients have developed their own consultant’s performance evaluation (CPE) procedures, the sharing of performance information, though desirable, may not be too meaningful as the results of evaluation could be inconsistent. There is a need to examine whether a unified framework can be derived for CPE. The aim of this paper is to improve the transparency and rigorousness of CPE through the establishment of an evaluating framework for gauging the performance of engineering consultants. In this paper, a comprehensive set of evaluation criteria is identified, and the significance of these criteria is discussed through an empirical survey. Then, a multicriteria model for evaluating the performance of engineering consultants is presented. The results indicate that once an acceptable CPE framework is devised, the performance scores can be utilized for various purposes, including monitor and control, incentive and sanction, preselection, technical assessment, and bid evaluation.     

The use of chemotherapy resistance in cancer treatment

It is not inconceivable that everything except the basic structure of an office building could be prefabricated in the near future. Quality and schedule are nearly always improved with prefabrication due to the simple change from an uncontrolled work environment to a controlled one. One Ludgate Place, is a 23,600 m2, ￡30,000,000 speculative commercial development in central London. This high quality office building has an exposed structural steel frame, within which are fitted prefabricated cladding panels. This paper combines the results from two research programs. The first in the area of prefabrication and the second in the management of high quality cladding construction. The writers describe the Ludgate Place project, incorporating the cladding design, testing, assembly, and installation. Factors that influenced the decision to use prefabrication are presented and evaluated, namely, cost; time; quality; past experience; design; weather joints; performance tests; site logistics; and safety. Construction interfaces and tolerances, particularly between cladding and structure, are discussed, and the future of prefabricated cladding is considered.     

Vibration Serviceability of a Building Floor Structure. II: Vibration Evaluation and Assessment

People are generally very sensitive to unexpected vibrations. Very small levels of building floor movements due to activities such as walking can become annoying to occupants. Accurate prediction, evaluation, and assessment of vibrations can greatly assist engineers and architects to design cost-effective building structures without such problems. In an attempt to clarify some of the issues related to this common serviceability problem, this paper presents a study of the various parameters used for the evaluation and assessment of building vibrations. Provisions of several current standards and design guides commonly used in North America and U.K. to evaluate and assess building vibrations as related to human perception and comfort are reviewed. These provisions are then applied using the vibrations measured during a number of walking tests conducted on a large cantilevered office building floor. Based on the results of this study, it is concluded that the vibration dose value (VDV) recommended by some standards and design guides provides a consistent and reasonable method of evaluation of building floor vibrations. In addition, new relationships between VDV, peak frequency-weighted acceleration, and crest factor are established to estimate the VDV.     

IFC-Based Framework for Evaluating Total Performance of Building Envelopes

Evaluating the overall performance of buildings has emerged as a trend in building engineering in recent years. Several programs that evaluate building performance have been developed or are being developed in different regions of the world. The building envelope performance assessment tool was initiated at Concordia University based on the feedback received from manufacturers. After briefly introducing the development of the tool, this paper presents an integrated framework which applies information technology and the international standard Industry Foundation Classes (IFC) to ensure that the building envelope satisfies energy requirements as well as other requirements such as moisture and thermal performance, concurrently. The framework is designed to extract geometric and material layers’ data of a house from computer-aided design (CAD) drawings in IFC data model, link to performance evaluation applications, such as HOT2000 and MOIST3.0, and compare evaluation results with a set of criteria. To demonstrate the functionalities of this framework, a prototype system has been developed including a preprocessor that imports the building model from an IFC-compatible CAD application, an application integrator, and a postprocessor. Finally, a case study, which aims to validate this prototype system, is discussed in detail.     

Validation and Optimization of an Equilibrium Model of a Hot-Lime-Softening Treatment System

This paper describes the development and validation of an equilibrium model of an industrial hot-lime-softening boiler-water-treatment unit for a large-scale nickel processing facility in which approximately 6.6?ML per hour of water is processed. In the industrial process, multiple water sources of varying quality are combined before the softening treatment, which makes control and optimization of the softening unit complicated and has brought about the necessity of a robust numerical model of water treatment. In this paper, the numerical thermodynamic and adsorption relations describing the softening treatment process are presented. Lime, magnesia, and soda ash additions are modeled. Emphasis has been placed on calcium, magnesium, and silica treatments as these are of most relevance to the industry. Jar tests described in this paper are used to determine adsorption relations, estimate statistical uncertainties, validate the model performance, and optimize the model parameters. Parameter estimations for equilibrium constants are undertaken and provide insights into the range of model validity and interactions between additions and softened water quality. Further jar testing is utilized to evaluate the effectiveness of using the model to numerically derive optimal chemical additions.     

General Contractors' Management: How Subs Evaluate IT

A large set of criteria by which top quality subcontractors evaluate the managerial performance of general contractors under whose management they have worked during the construction process and by which they may differentiate their bids to different generals for the same future project are listed and described. These criteria can also be seen as the intrinsic managerial, cost‐and time‐sensitive factors by which general contractors or any manager of construction could improve performance, competitiveness and profitability. It also describes separate, “most important” and “super‐important” subsets of the foregoing criteria∕factors for office and site staff, etc., and the range of effects of the generals' good and bad managerial performance against these criteria∕factors on the costs and duration of the subcontractors' work. The cost and duration effects, etc., that each lump sum bidding general contractor and appointed construction management agent has on the subcontractors' work are compared, and the carefully formatted research process which produced these results is outlined.     

Effect of Live-Load Deflections on Steel Bridge Performance

This paper presents an evaluation of the influence of AASHTO live-load deflection criteria on the performance of steel I-girder bridges. Background information is provided regarding previous research studies focused at understanding the role and suitability of live-load deflection limits on steel bridge design. Further, the results of an extensive survey of state transportation departments regarding the use of these limitations is provided. The results of a computer analysis package developed to evaluate the variability of these survey results are also presented. Last, a series of analyses of existing steel bridges conducted to examine the effects of the live-load deflection limits on typical and damaged bridges to determine the role that these limits play in overall superstructure performance is provided.     

基于云理论的大坝整体性态评价模型

现有的大坝整体性态评价方法以定性评价为主,主观性较强。针对这一问题,以单测点监控模型的计算值与监测仪器实测值之间的残差为基础,提出采用多测点融合残差表征大坝整体性态。结合信息熵理论研究了不同测点的残差变化规律,从而对各测点残差的融合权重进行了分配,计算了融合残差。通过对融合残差进行分布分析,利用逆向云发生器、正向云发生器建立了表征大坝不同性态的概念云,即评价标准。在此基础上,结合云相似度算法,建立了大坝整体性态的评价模型。算例表明,该模型能够有效识别大坝监测资料中的异常测值,并能够定量、客观地评价大坝整体性态,评价结果合理、可靠,可为保障大坝安全运行提供重要参考。      

SuretyAssist: Fuzzy Expert System to Assist Surety Underwriters in Evaluating Construction Contractors for Bonding

In construction, many owners mitigate the risk of unforeseen contractor default by accepting only bonded contractors who must endure a rigorous evaluation process by surety brokers and surety underwriters. This evaluation process includes a financial analysis and a review of work on hand and past performance, all of which have reliable structured methods for their evaluation. Additionally, a number of subjective criteria are considered that are more difficult to capture and assess objectively but which can be modeled effectively using fuzzy logic. The purpose of this paper is to illustrate how fuzzy logic and expert systems can be combined to provide a structured approach to evaluating contractors for surety underwriting purposes. Fuzzy logic is used to model both the objective and subjective factors considered in contractor evaluation using linguistic terms, and expert rules are used to capture the surety experts’ reasoning process. A fuzzy expert system, SuretyAssist, is presented that can be used to provide an initial evaluation of general contractors as well as periodic reviews to determine whether or not to accept them as clients for bonding. SuretyAssist was validated using 31 actual cases of contractor evaluation and found to be accurate in 81% of the cases.     

Continuous Value Enhancement Process

The demand for sustainable buildings is an important emerging trend in the building industry. However, the task of delivering these facilities is more difficult than for traditional projects and existing project management techniques struggle to handle the high levels of complexity present. A process-based model, called the continuous value enhancement process (CVEP), was developed to systematically generate and evaluate project alternatives leading to high performance solutions that improve project performance and increase levels of sustainability. Developed specifically to address the challenges facing the Pentagon renovation—which will become the world’s largest green office renovation—CVEP is tested to research its ability to support project management decision making in ways that elevate sustainability and project performance. The key contributions of this model include the integration of sustainable objectives into project management practices, and the development of a metric for measuring the quality and focus of project team decisions.     

Benchmark Problem for Response Control of Wind-Excited Tall Buildings

This paper presents an overview and problem definition of a benchmark problem for the response control of wind-excited tall buildings. The building considered is a 76-story 306 m concrete office tower proposed for the city of Melbourne, Australia. The building is slender with a height to width ratio of 7.3; hence, it is wind sensitive. Wind tunnel tests for such a 76-story building model have been conducted at the University of Sydney and the results of across-wind data are used in the present benchmark problem. Either active, semiactive, or passive control systems can be installed in the building to reduce the wind response, although only an active control sample problem has been worked out to illustrate the control design. In the case of active control systems, either an active tuned mass damper or an active mass driver can be installed on the top floor. In the case of passive or semiactive systems, such as viscous dampers, viscoelastic dampers, electrorheological, or magnetorheological dampers, etc., control devices can be installed in selected story units. Control constraints and evaluation criteria are presented for the design problem. A simulation program based on the linear quadratic Gaussian technique has been developed and made available for the comparison of the performance of various control strategies.     

Evaluation of Knowledge Representation Schemes as a Prerequisite toward Development of a Knowledge-Based System

In developing a knowledge-based system, it is crucial to use an appropriate knowledge representation scheme (KRS) for efficient working of the developed system. However, it is difficult to select an appropriate KRS due to lack of a generalized method of comparison among the variety of schemes available. The objective of this paper is to discuss a generalized method for comparative evaluation of KRS, based on criteria of expressiveness and performance. The discussed method has been implemented for evaluation of four widely used KRSs: rule-based model, object-based model, relational model, and hybrid model. Evaluation is being carried out using a knowledge base for zonation of landslide hazard. Based on the criteria of expressiveness and performance, it has been found that hybrid-based KRS is best for representation of the domain knowledge available in the Indian Standard Code 14496-1998 (Part-II).     

A Fuzzy Decision Framework for Contractor Selection

Contractor selection is the process of selecting the most appropriate contractor to deliver the project as specified so that the achievement of the best value for money is ensured. Construction clients are becoming more aware of the fact that selection of a contractor based on tender price alone is quite risky and may lead to the failure of the project in terms of time delay and poor quality standards. Evaluation of contractors based on multiple criteria is, therefore, becoming more popular. Contractor selection in a multicriteria environment is, in essence, largely dependent on the uncertainty inherent in the nature of construction projects and subjective judgment of decision makers (DMs). This paper presents a systematic procedure based on fuzzy set theory to evaluate the capability of a contractor to deliver the project as per the owner’s requirements. The notion of Shapley value is used to determine the global value or relative importance of each criterion in accomplishing the overall objective of the decision-making process. The research reported upon forms part of a larger study that aims to develop a fuzzy decision model for construction contractor selection involving investigating multiple criteria selection tendencies of construction clients, relationship among decision criteria, and construction clients’ preferences of criteria in the contractor selection process. An illustration with a bid evaluation exercise is presented to demonstrate the data requirements and the application of the method in selecting the most appropriate contractor for the project under uncertainty. The proposed model is not intended to supplant the work of decision-making teams in the contractor selection process, but rather to help them make quality evaluations of the available candidate contractors. One major advantage of the proposed method is that it makes the selection process more systematic and realistic as the use of fuzzy set theory allows the DMs to express their assessment of contractors’ performance on decision criteria in linguistic terms rather than as crisp values.     

Grid-Enabled Simulation-Optimization Framework for Environmental Characterization

Many engineering and environmental problems that involve the determination of unknown system characteristics from observation data can be categorized as inverse problems. A common approach undertaken to solve such problems is the simulation-optimization approach where simulation models are coupled with optimization or search methods. Simulation-optimization approaches, particularly in environmental characterization involving natural systems, are computationally expensive due to the complex three-dimensional simulation models required to represent these systems and the large number of such simulations involved. Emerging grid computing environments (e.g., TeraGrid) show promise for improving the computational tractability of these approaches. However, harnessing grid resources for most computational applications is a nontrivial problem due to the complex hierarchy of heterogeneous and geographically distributed resources involved in a grid. This paper reports and discusses the development and evaluation of a grid-enabled simulation-optimization framework for solving environmental characterization problems. The framework is designed in a modular fashion that simplifies coupling with simulation model executables, allowing application of simulation-optimization approaches across problem domains. The framework architecture utilizes standard communications protocols and the message passing interface with an application programming interface to establish a connection between a centralized search application and simulation models running on TeraGrid resources. Sets of performance and scalability results for solving a groundwater source history reconstruction (SHR) problem are presented. The results show that for a given set of resources, parameters controlling the granularity at various levels of parallelism play an important role in the overall parallel performance. A production run for solving the SHR problem using three geographically distributed grid resources indicates that even in a cross-site grid environment a factor of 90 speedup is possible using 140 computer processors.     

Impressions of psychotherapists' offices.

For counseling settings, research suggests that softness, personalization, and order might affect the experience and the perceived expertness, trustworthiness, and social attractiveness of the therapist. This article discusses exploratory studies on college students' perception of the counseling office environment and whether the likely client experience was associated with the softness/personalization and order of the office. As stimuli, the studies used 30 color photographs of psychotherapists' offices viewed from the client's perspective. After obtaining ratings of the characteristics of each office, we obtained ratings from different groups of students of the quality of care and comfort expected in each office (Study 1) and how qualified, bold, and friendly the therapist in the office would be (Study 2). Additional studies examined the likelihood of choosing a therapist based on the office, and the first thought or feeling that came to mind about the office, the therapist, and the patient experience. There were strong correlations in response between groups (by whether they had experienced therapy; their level in school; their gender; and their major, location, and school size). The quality of care, comfort, therapist boldness, qualifications of the therapist, and the likelihood that one would choose a therapist based on the office improved with increases in the office's softness/personalization and order. Friendliness improved with increases in softness/personalization. The office choices, open-ended responses, and reported reasons for the ratings confirmed the importance of softness (comfort) and order. Research should test longer term exposure and behavior. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Budgeting for Facility Maintenance and Repair. II: Multicriteria Process for Model Selection

The second of two in a series, this paper presents an objective process for selecting an appropriate model for facility maintenance and repair budgeting. Three model evaluation criteria relating facility attributes to maintenance and repair costs—consideration of the facility's physical characteristics and environment, building system and component life cycles, and penalty costs brought on by deferral of maintenance—are introduced. The expense of supplying the necessary data for a model's implementation, given the model user's existing database, is presented as a fourth evaluation criterion. The relative merits of 18 available budgeting models are then assessed against these criteria using various multicriteria decision-making tools: Analysis of dominance, with results displayed via a Hasse diagram; lexicographic ordering; and the technique for order preference by similarity to ideal solution. The results of the evaluation demonstrate how the preferred alternative can change in response to a decision-maker's priorities. Conversely, the selection process can provide considerable insight into these models with very little knowledge about the value system or philosophy of the model users and the decision makers.     

Simulation Model for Level Furrows. II: Description, Validation, and Application

In a companion paper, experimental evidence was elaborated to confirm that in particular circumstances the performance of level-furrow irrigation can exceed that of level-basin irrigation. The application of a single furrow simulation model to an irrigation event in a level-furrow field resulted in large estimation errors. To overcome them, the development and validation of a numerical model of level-furrow irrigation is reported in this work. The model is based on the interconnection of a number of one-dimensional channels. The individual channels are connected using confluence or bifurcation points. Furrow infiltration is modelled through a Kostiakov infiltration equation including the furrow discharge as an independent variable. The proposed model is validated using the experimental level furrow evaluation presented in the companion paper. Finally, the model is applied to explore the conditions in which level furrow irrigation can outperform level basin irrigation. The proposed model stands as a valuable tool in the design and management of level furrow irrigation systems.     

Thermal comfort in offices:comfort values and optimization of indoor control variables

In order to search for reasonable air-conditioned indoor control variables and save energy consumption and meet tO need of personal thermal comfort,a method which is based on numerical simulation is employed to optimize indoor control variables.Computational fluid dynamics(CFD)is used to describe thermal state of office.An optimal method is proposed in this paper,dual neural network model is firstly used to acquire reliable information,data from CFD model are pre-processed,and the remaining data are used to train artificial neural networks(ANN),then CFD model is replaced by ANN model to reduce computational cost when is optimized,indoor control variables are optimized by genetic algorithm.Simulation results show that indoor thermal comfort is improved obviously,and the energy cost is decreased accordingly.     

Noise Control and Speech Privacy Guidelines for Office Building Design

Noise control is required to provide an indoor environment free from the stress of unwanted noise and to provide a measure of speech privacy. There is a need for the development of guidelines to be used by building designers to ensure that user comfort is taken into consideration. The focus of this paper is on the development of guidelines as advice to designers to facilitate systems replacement in new buildings and the introduction of new systems in the future. Some aspects of noise control and speech privacy in various locations in office buildings have been addressed. Responses from 92 design professionals (architects and engineers) in nine countries to a questionnaire on noise control and speech privacy in office buildings have been summarized in the form of guidelines for use by building designers.