Evaluation of Solid Waste Management System Using Fuzzy Composition

Evaluating the best alternative for a solid waste management system often requires decision makers to consider conflicting, vague, and uncertain information. Fuzzy set theory offers a possible means of managing these kinds of data or information. In this study, we propose a systematic approach to evaluating a solid waste management system in a fuzzy environment. The approach employs three main concepts: linguistic variables, fuzzy numbers, and an analytic hierarchy process. The linguistic variables are used to represent the degree of appropriateness of decision criteria, which are vague or uncertain. These linguistic variables are then translated into fuzzy numbers to reflect their uncertainties and aggregated into the final fuzzy decision value using a hierarchical structure. Through a case study, the approach is applied to the evaluation of a solid waste management system consisting of four different treatment alternatives. The results demonstrate that the developed approach can be a useful tool for evaluating a solid waste management system, where criteria are vague or imprecise.     

Decision analysis to optimize the outcomes for Class II Division 1 orthodontic treatment

Selection of the treatment method of choice in orthodontics is usually a question of the clinician's personal preference and is generally based on subjective criteria. Orthodontic treatment of malocclusions is unlike treatment of a disease and hence terms such as success and failure are relative and undefined. Ideally, both patients and providers should be able to arrive at treatment decisions that have the greatest potential for optimum outcomes at minimal cost and risks. This article applies the method of decision analysis to demonstrate how policy choices between "one-stage" or "two-stage" treatment of Class II Division 1 malocclusions for children between 11 and 14 years old can be based on objective criteria. A decision tree was designed to yield the value of payoffs, or outcomes, at each of the possible terminal nodes, and the probability of each payoff. Both positive (ie, improvement in malocclusion) and negative (ie, extraction of teeth and long treatment duration) attributes of outcomes were considered, and numerical values, or "utilities," were assigned to each outcome. For this model, one-stage nonextraction treatment yields the highest probability of maximum benefit. Further applications of decision analysis to resolve clinical uncertainties in orthodontics are discussed.     

Beyond lithium in the treatment of bipolar illness

Primary non-Hodgkin lymphoma of the stomach is a rare disorder for which clinical management has not yet been settled completely. Faced with the many uncertainties associated with the selection of a treatment for a patient with this disorder, it is difficult to determine the treatment that is optimal for the patient, as well as the prognosis to be expected. The development of a decision-theoretic model of non-Hodgkin lymphoma of the stomach is described. The model aims to assist the clinician in exploring various clinical questions, among others questions concerning prognosis and optimal treatment. Central to the model is a probabilistic network that offers an explicit representation of the uncertainties underlying the decision-making process. The model has been incorporated in a decision-support system. Preliminary evaluation results indicate that the performance of the model in its present form matches the performance of experienced clinicians.     

基于博弈论的主客观组合权重TOPSIS采矿方法优选

针对当前采矿方法优选过程中,权重计算时主观权重信息丢失较多且占比过大的问题,将主客观权重相结合,计算出综合权重,并运用于采矿方法优选体系。首先,利用模糊扩展层次分析法（FEAHP）计算主观权重,最大程度地保存主观信息;然后,利用CRITIC客观赋权法计算客观权重,并运用博弈论原理将主客观权重相结合,得到综合权重;最后,结合逼近理想解的排序方法（TOPSIS）,建立基于博弈论的主客观组合权重TOPSIS采矿方法优选模型。将所建立的基于博弈论的主客观组合权重TOPSIS采矿方法优选模型运用于工程实例中,对姑山露天铁矿驻留矿体的采矿方法进行优选,计算出4种备选方案（上向进路胶结充填法、浅孔留矿嗣后充填法、上向水平分层充填法和下向水平分层充填法）的相对贴近度分别为0.4547、0.4441、0.5872和0.4072,得出上向水平分层充填法为最优方案。研究结果与矿山工程实例相符,证明基于博弈论组合的主客观权重值比以往单一的赋权法得到的权重值更加合理,建立的模型更科学。     

Risk-Based Prioritization of Terrorist Threat Mitigation Measures on Bridges

This paper describes a risk-based methodology developed to facilitate prioritization of terrorist threat mitigation strategies on individual bridges. Numerous risk-based methods have been used for prioritization among a group of bridges or other assets. However, this methodology is unique in that it is specifically designed to focus on a single bridge and the risk associated with each of its many individual structural components. “Risk,” as discussed herein, describes the relative potential for a terrorist attack against a specific component and the associated consequence from the attack. It is based on such factors as the component’s importance to overall structural stability, its location and thus accessibility to terrorists, and its resistance to the specific threat. The component-specific risk factors and their modifying attributes are described. The result of the methodology is a rank-ordered list of components most at risk to an attack, allowing prioritization and optimization of the mitigation design for the bridge. Once mitigation schemes are identified, the methodology can then be utilized to recalculate mitigated risk, allowing for a direct indication of cost/benefit of the mitigation design. The methodology and comparison criteria are described and a simple application example is given to demonstrate the usefulness of the methodology.     

Risk for falls in the elderly. Role of activities of daily living and of the subjective assessment of health status. A case-control study

Prevention and treatment of falls in the elderly are today important questions the primary care physicians has to face. It is known that falls are associated with numerous factors related to health status and demographic variables. The role played by the activities of daily living (ADL) and by a negative subjective health rating of one's own health status, and how both could increase the incidence of diseases due to home accidents, is less known. This case-control study carried out in the accident ward of S. Camillo Hospital in Rome, studied 110 elderly patients, who suffered from fractures caused by falls. The main goal was to identify the possible associations among falls, ADL and lower limb mobility, as well as studying the importance of a positive subjective health rating to prevent these accidents. Controls have been selected in other wards of the same hospital and in an out-patient's department. Results show that the risk of falling is associated with previous falls (odds ratio = 3.81), with poor mobility at home (OR = 2.49), outside home (OR = 2.06), out of one's own area (OR = 1.74), and with a negative subjective health rating (OR 3.33). Multivariate analysis has pointed out that a negative subjective health rating keeps being a statistically significant risk factor for falls (OR = 2.86), independently from the objective health conditions of the subject. Such a negative subjective rating often develops itself just as a consequence of a previous fall without injuries.     

Fuzzy Logic Based Condition Rating of Existing Reinforced Concrete Bridges

Fuzzy logic is a means for modeling the uncertainty involved in describing an event/result using natural language. The fuzzy logic approach would be particularly useful for remedying the uncertainties and imprecision in bridge inspectors’ observations. This study explores the possibilities of using fuzzy mathematics for condition assessment and rating of bridges, developing a systematic procedure and formulations for rating existing bridges using fuzzy mathematics. Computer programs developed from formulations presented in this paper are used for evaluating the rating of existing bridges, and the details are presented in the paper. In this approach, the entire bridge has been divided into three major components—deck, superstructure, and substructure—each of which is further subdivided into a number of elements. Using fuzzy mathematics in combination with an eigenvector-based priority setting approach, the resultant rating set for the bridge has been evaluated based on the specified ratings and importance factors for all the elements of the bridge. Then the defuzzified value of the resultant rating fuzzy set becomes the rating value for the bridge as a whole. It is argued that the methodology presented in this paper would help the decision makers/bridge inspectors immensely.     

Contaminant Transport Model for Unsaturated Soil Using Fuzzy Approach

Contaminant transport in the unsaturated zone is important for managing water resources and assessing the damage due to contamination in the field of irrigation, water management, wastewater management, and urban and agricultural drainage systems. Deterministic modeling which is widely used for contaminant transport is not adequate because it considers model input parameters as well-defined crisp values and hence does not account for uncertainties and imprecision. This paper presents a contaminant transport model based on fuzzy set theory to simulate water flow and contaminant transport in the unsaturated soil zone under surface ponding condition. Among all soil hydraulic parameters that have uncertainty associated with them, saturated hydraulic conductivity was found to be the most sensitive to model outputs. Trapezoidal fuzzy numbers were used to express the uncertainties associated with saturated hydraulic conductivity. The incorporation of uncertainties into contaminant transport model is useful in decision making, as it yields scientifically and practically based estimates of contaminant concentration.     

Objective and subjective socioeconomic status and susceptibility to the common cold.

Objective: We ask whether subjective socioeconomic status (SES) predicts who develops a common cold when exposed to a cold virus. Design: 193 healthy men and women ages 21-55 years were assessed for subjective (perceived rank) and objective SES, cognitive, affective and social dispositions, and health practices. Subsequently, they were exposed by nasal drops to a rhinovirus or influenza virus and monitored in quarantine for objective signs of illness and self-reported symptoms. Main Outcome Measures: Infection, signs and symptoms of the common cold, and clinical illness (infection and significant objective signs of illness). Results: Increased subjective SES was associated with decreased risk for developing a cold for both viruses. This association was independent of objective SES and of cognitive, affective and social disposition that might provide alternative spurious (third factor) explanations for the association. Poorer sleep among those with lesser subjective SES may partly mediate the association between subjective SES and colds. Conclusions: Increased Subjective SES is associated with less susceptibility to upper respiratory infection, and this association is independent of objective SES, suggesting the importance of perceived relative rank to health. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Clinical and laboratory basis for the diagnosis and understanding of neonatal metabolic diseases

The evaluation, classification, and treatment of carpal instability continues to be one of the most controversial topics in hand surgery. One explanation is the lack of standardized findings and radiographic criteria. No good modality to date has been proposed to accurately aid in evaluating carpal instability. Wrist arthroscopy has become increasingly useful in the assessment of mechanical wrist pain. With this technology, specific patterns of injury can more accurately be identified by direct visualization. This will also aid in implementing a reproducible, less subjective means of describing wrist instability. The treatment can then be focused on management of the specific ligamentous injury responsible for the pattern of instability visualized. The following is an attempt to categorize these instability patterns as seen through arthroscopy and provide our proposed treatment options.     

项目管理在信息系统集成项目中的应用

以某饮用水源水质自动监测系统为例,从项目管理中的范围管理、质量管理、成本管理、时间管理、风险管理等方面,对项目管理在信息系统集成项目中的应用进行了阐述。     

Improving Objectivity in Procurement Selection

Selecting a procurement strategy for construction projects is inherently subjective. The decision is often intuitively based on the previous experience and knowledge of the decision maker. An objective-subjective procurement selection method is proposed. The method takes into account the need to have an objective base for strategy comparison through the use of multiattribute utility technology. Allowing the decision maker to assign importance ratings for the selection criteria also accommodates individual preferences and project specificities. The analytical hierarchical process based importance ratings assignment method improves both the objectivity and the reliability of the assessment. Applications in real cases suggest positive potential use of the method.     

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.     

Polysomnographic and subjective sleep predictors of alcoholic relapse

Previous studies indicate that subjectively reported and objectively measured sleep abnormalities at baseline can increase the risk of relapse in treated alcoholics. However, previous studies did not include both subjective and objective sleep measures in the same group of patients. We utilized polysomnography and the Sleep Disorders Questionnaire to determine if baseline polysomnography increased the ability to predict relapse beyond the prediction with subjective measures alone, after controlling for nonsleep variables that were associated with relapse. We followed 74 patients with a DSM-III-R diagnosis of alcohol dependence, of whom 36 relapsed to at least some drinking during an average follow-up interval of 5 months. Univariate analyses revealed that relapsed patients did not differ from abstinent patients at baseline in demographics or psychiatric co-morbidity, but they had more prior treatment episodes for alcoholism, more difficulty falling asleep, more complaints of abnormal sleep, and, on polysomnography, longer sleep latencies, shorter rapid eye movement sleep latencies, and less stage 4 sleep percentage than abstinent patients. With a series of logistic regression analyses, which controlled for age and gender, we demonstrated that sleep measures improved the prediction model compared with nonsleep variables alone, and that polysomnography-measured sleep latency was the most significant predictor variable. We conclude that subjective and objective measures of baseline sleep are predictors of relapse in treated alcoholic patients. These data also suggest that neurophysiological dysfunction contributes strongly to the etiology of relapse. Finally, sleep disturbance warrants clinical attention as a target of alcoholism treatment.     

Alcohol expectancies, problem drinking, and adverse health consequences

This study evaluated a measure of positive and negative expected effects of alcohol and their subjective evaluation in the identification of college freshmen at high risk for problem drinking and associated morbidities. It was hypothesized that greater expectations of positive outcomes and fewer negative evaluations of negative outcomes would be associated with reports of heavier drinking and more alcohol-related health problems. College freshmen (n = 328) completed a standardized measure of expectations and subjective evaluations of positive and negative outcomes associated with drinking, and a questionnaire assessing drinking patterns and common alcohol-related health problems. Fifty-two percent of students were male and the mean age was 17.9 years (SD = 0.5). Students' expectations of positive outcomes and their subjective evaluations of both positive and negative outcomes from drinking were significantly correlated with drinking and alcohol-related health problems indices (p < 0.001). Gender, expectation of positive outcomes, and evaluation of negative outcomes explained 29% of the variance in drinking and 15% of the variance in alcohol-related health problems indices. Heavier-drinking students and those reporting more health problems expected more positive effects on their sociability and sexuality (p < 0.03) and were less concerned about cognitive and behavioral impairment as a result of drinking (p < 0.001). Students with more health problems were less concerned that drinking would lead to risk-taking or aggressive behavior (p < 0.003). Positive and negative outcome expectancies and their subjective evaluations accounted for a significant portion of the variability in drinking and alcohol-related health problems.(ABSTRACT TRUNCATED AT 250 WORDS)     

Predictors of heavy drinking during and following treatment.

Alcohol dependence has been described as a relapsing condition and it has been proposed that alcohol lapses could potentially be explained by dynamic associations between contextual, interpersonal, and intrapersonal risk factors. Yet, few studies have tested the associations between risk factors in the prediction of lapse dynamics. The current study was a secondary analysis of data from the COMBINE study (n = 1,383; COMBINE Study Research Group, 2003). The goal of the current study was to examine static (alcohol dependence severity, treatment history, marital status, psychiatric symptoms) and dynamic (negative affect, craving, stress) predictors of heavy drinking during the course of treatment and up to one year following treatment. Results from dynamic latent difference score models indicated that higher levels of static and dynamic risk and increased dynamic risk over time were significantly associated with greater increases in heavy drinking. Likewise, more frequent heavy drinking and higher static risk predicted higher levels of dynamic risk. In addition, changes in dynamic risk factors significantly mediated the association between changes in heavy drinking and both psychiatric symptoms and treatment history. It is important to note that while the effects of static and dynamic risk factors in the prediction of heavy drinking were statistically significant, the magnitude of the effects were small. The current study provided partial support for a dynamic model of relapse; however future research using intensive longitudinal data collection and more advanced statistical techniques could further elucidate lapse dynamics and potentially improve relapse prevention planning. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Microdosimetric specification of the radiation quality of a d(48.5)+Be fast neutron therapy beam produced by a superconducting cyclotron

The proportional counter microdosimetric technique has been employed to quantify variations in the quality of a d(48.5)+Be fast neutron beam passing through a homogeneous water phantom. Single event spectra have been measured as a function of spatial location in the water phantom and field size. The measured spectra have been separated into component spectra corresponding to the gamma, recoil proton and alpha plus heavy recoil ion contribution to the total absorbed dose. The total absorbed dose normalized to the "monitor units" used in daily clinical use has been calculated from the measured spectra and compared to the data measured with calibrated ion chambers. The present measurements agree with the ion chamber data to within 5%. The RBE of the neutron beam is assumed to be proportional to the microdosimetric parameter y* for the dose ranges pertinent to fractionated neutron therapy. The relative variations in y*, assumed to be representative of variations in the RBE are mapped as a function of field size and spatial location in the phantom. A variation in the RBE of about 4% for points within and 8% for points outside a 10 cm x 10 cm field is observed. The variations in the RBE within the beam are caused by an increase in the gamma component with depth. An increase in the RBE of about 4% is observed with increasing field size which is attributed to a change in the neutron spectrum. Compared to the uncertainties in the prescribed dose, associated with uncertainties in the clinically used RBE, variation in the RBE between various tissues, and other dosimetric uncertainties caused by factors such as patient inhomogeneities, patient setup errors, patient motion, etc., the measured spatial RBE variations are not considered significant enough to be incorporated into the treatment planning scheme.     

Fuzzy Parametric Programming Model for Integrated Solid Waste Management under Uncertainty

Solid waste management (SWM) is increasingly becoming a challenging task for the municipal authorities due to increasing waste quantities, changing waste composition, decreasing land availability for waste disposal sites, and increasing awareness about the associated environmental risk. This paper presents a fuzzy parametric programming model for the selection of the treatment and disposal facilities and optimum capacity planning and waste allocation under uncertainty associated with the long-term planning for SWM. The model dynamically locates the facilities and allocates the waste considering fuzzy waste quantities and capacities of waste-management facility in a multiperiod planning for integrated SWM. The model addresses uncertainty in waste quantity as well as uncertainties in the operating capacities of waste-management facilities. An example problem has been presented to demonstrate the usefulness of the proposed model in making the planning decisions related to SWM and achieving an efficient plan. The model is solved at different levels of membership function for the alternative solutions with respect to objective. The example problem reveals that the uncertainty in the waste quantity is likely to affect the planning for waste treatment/disposal facilities more as compared with the uncertainty in the capacities of the waste-management facilities. The relationship between increase in waste quantity and increase in the total cost involved in waste management is found to be nonlinear. The modeling results are useful for generating a range of decision alternatives under various economic conditions. They are valuable for analyzing the existing waste-management practices, the long-term capacity planning for the city’s waste-management system, and the identification of desired policies regarding waste generation and management.     

Case-control study of bladder cancer and water disinfection methods in Colorado

A population-based case-control study of bladder cancer and drinking water disinfection methods was conducted during 1990-1991 in Colorado. Surface water in Colorado has historically been disinfected with chlorine (chlorination) or with a combination of chlorine and ammonia (chloramination). A total of 327 histologically verified bladder cancer cases were frequency matched by age and sex to 261 other-cancer controls. Subjects were interviewed by telephone about residential and water source histories. This information was linked to data from water utility and Colorado Department of Health records to create a drinking water exposure profile. After adjustment for cigarette smoking, tap water and coffee consumption, and medical history factors by logistic regression, years of exposure to chlorinated surface water were significantly associated with risk for bladder cancer (p = 0.0007). The odds ratio for bladder cancer increased for longer durations of exposure to a level of 1.8 (95% confidence interval 1.1-2.9) for more than 30 years of exposure to chlorinated surface water compared with no exposure. The increased bladder cancer risk was similar for males and females and for nonsmokers and smokers. Levels of total trihalomethanes, nitrates, and residual chlorine were not associated with bladder cancer risk after controlling for years of exposure to chlorinated water.     

Reliability Analysis of Partial Safety Factor Design Method for Cantilever Retaining Walls in Granular Soils

Uncertainties in the geotechnical design variables and design equations have a significant impact on the safety of cantilever retaining walls. Traditionally, uncertainties in the geotechnical design are addressed by incorporating a conservative factor of safety in the analytical model. In this paper, a risk-based approach is adopted to assess the influence of the geotechnical variable and design equation uncertainties on the design of cantilever retaining walls in sand using the “partial factor of safety on shear strength” approach. A random model factor based on large-scale laboratory test data from the literature has been incorporated into the reliability analyses to quantify the uncertainty in the geotechnical calculation model. Analyses conducted using Monte Carlo simulation show that the same partial factor can have very different levels of risk depending on the degree of uncertainty of the mean value of the soil friction angle. Calibration studies show the partial factor necessary to achieve target probability values of 1 and 0.1%.