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21.
刘强  吕晶  白文琦 《价值工程》2015,(11):163-166
本试验以砂浆性能为研究对象,采用Box-Behnken的中心组合实验设计及响应面分析方法对腻子粘结强度进行预测研究。试验选用三因素三水平的响应曲面分析法,建立了粘结强度的二次多项数学模型,并以粘结强度为响应值作响应面和等高线,考察了水粉比、灰粉比和胶粉比对粘结强度的影响,并根据实际选择响应曲面方程,利用最小二乘法估计相应的系数,剔除最不显著因素,建立最终的数学方程。结果表明:该预测模型能很好地描述粘结强度与水粉比、灰粉比和胶粉比之间的关系,可以对腻子粘结强度进行分析和预测,为砂浆性能研究提供一种新方法。  相似文献   
22.
Although the study of flow has recently received a lot attention, little is published about what factors controllable by firms influence its formation. Furthermore, there is a lack of knowledge between the relationship of website atmospheric cues and flow experience. Using a stimulus–organism–response framework (S–O–R framework) as the theoretical basis, this study examines the impact of consumer perceptions of website atmospheric cues (informativeness, effectiveness and entertainment) on the development of flow and its subsequent impact on purchase intention and satisfaction. A self-administered online survey was used for data collection through an internet market research firm which randomly selected individuals from its online panel. Our results support the validity of the S–O–R framework in the context of online tourism and indicate that flow fully mediates the three site atmospheric cues with regards to purchase intention and satisfaction with the travel website. This study enhances our understanding on the determinants of online purchase intention and satisfaction as well as on how a proper web atmospheric design alters consumer shopping experience which entices favourable purchase intention and generates satisfaction.  相似文献   
23.
The increasing use of demand‐side management, as a tool to reliably meet electricity demands at peak time, has stimulated interest among researchers, consumers and producer organiza‐tions, managers, regulators and policymakers. This research reviews the growing literature on models which are used to study demand, customer base‐line (CBL) and demand response in the electricity market. After characterizing the general demand models, the CBL, based on which the demand response models are studied, is reviewed. Given the experience gained from the review and existing conditions, the study combines an appropriate model for each case for a possible application to the electricity market; moreover, it discusses the implications of the results. In the literature, these aspects are studied independently. The main contribution of this survey is attributed to the treatment of the three issues as sequentially interdependent. The review is expected to enhance the understanding of the demand, CBL and demand response in the electricity market and their relationships. The objective is conducted through a combination of demand and supply side managements in order to reduce demand through different demand response programs during peak times. This enables electricity suppliers to save costly electricity generation and at the same time reduce energy vulnerability.  相似文献   
24.
Abstract

Patient-reported outcome measures (PROMs) are used to collect information directly from patients. They may cover several different types of outcomes ranging from symptoms, functioning, utility, satisfaction, through to quality-of-life (QoL). They generally consist of self-completed questionnaires that can be administered by means of hard copies or in a range of electronic formats. PROMs vary considerably in terms of the constructs they assess, the care with which they are developed, and their scientific quality. However, none of the PROMs available approach the quality of measurement achieved by measures/instruments used in physics. PROs are examples of latent variables. These are not directly observable, but can be inferred from, for example, responses to a questionnaire. The only measure of a latent variable that approaches the quality of measurement achieved by the physical sciences is the Lexile Framework for Reading. This framework is based on a construct theory that grew out of an analysis of several available reading measures. A specification equation was generated that was able to link the construct theory to scores obtained with the Lexile measure. A fundamental requirement of this quality of measurement is that the data collected with the model fit Rasch Measurement Theory (RMT). It is argued that PROM developers should aspire to match this level of measurement sophistication if their instruments are to provide valid insights into the impacts of disease and its treatment.  相似文献   
25.
This study conducted a large-scale survey in Dhaka, Bangladesh; the survey involved 95 major hospitals, more than 3000 emergency room patients, and 2 of the largest ambulance operators. Currently, most ambulances are parked within the vicinity of hospitals and are either dispatched or fetched by the acquaintances of the patient on demand, resulting in lengthy round trips. Reducing the response time of ambulances would certainly improve the emergency service, and pre-positioning of the ambulances could be a solution to reducing the response time. This study used two approaches to address the problem. First, the location-allocation problem was solved to find the optimal number of ambulance locations by maximising the demand coverage. Second, separate location-allocation for the peak and off-peaks, using K-means clustering, was applied to systematically optimise the ambulance positioning in small clusters near demand points. These approaches could substantially improve the existing emergency response time. Distributing ambulances near demand points yielded greater improvements in response time than when the ambulances are stationed near hospitals.  相似文献   
26.
Within the existing literature, the role of experience of risk on attitudinal and behavioural risk response has been relatively neglected. Recent research that draws on the psychological distance of climate change as a concept notes the importance of local, significant experience as a driver for encouraging appropriate response. The experience of flooding was used as the stimulus in this paper, and emphasis placed on whether direct and/or indirect experience of flood risk is associated with different responses to climate change risk. In order to explore the relationship between climate change risk experience and response in the form of on-farm mitigation and adaptation, this paper draws on a case study of farmers in England, many of whom have experienced flooding. Results from a quantitative survey undertaken with 200 farmers in Gloucestershire, England are discussed. Statistical analysis found experience of flooding to be significantly associated with a heightened concern for climate change. Although also finding an association between experience and behavioural response, the sample were most likely to be taking adaptive behaviour as part of normal practice, with factors such as lack of overall concern for climate change risk and absence of information and advice likely to be the main barriers to action. Risk communication needs to further emphasise the connection between climate change and extreme weather events to allow for farmers to perceive climate change as a relevant and locally salient phenomenon, and subsequent tailored information and advice should be offered to clearly illustrate the best means of on-farm response. Where possible, emphasis must be placed on actions that also enable adaptation to other, more immediate risks which farmers in this study more readily exhibited concern for, such as market volatility.  相似文献   
27.
刘琪 《价值工程》2015,(10):309-310
本文提出来在重要的不规则的工业结构设计过程中采用性能化抗震设计的方法及实现。主要阐述了结构抗震性能目标的确定方法,文章结合设计实例分析建筑结构的是否满足选定的抗震性能设计,旨在为其他建筑的抗震设计提供参考和借鉴作用。  相似文献   
28.
《Business Horizons》2021,64(6):735-741
South Korea has been evaluated as a country that is responding well to COVID-19. The Government of the Republic of Korea discloses where, when, and by which means of transportation people confirmed to have the virus have visited. Although disclosure of movement has contributed to flattening the curve and providing timely medical service, concerns about privacy infringement have also been raised. This article determines what factors influence privacy risk tolerance, looking specifically at threat severity, vulnerability, response efficacy, and response cost. We also provide implications for the preparation of better countermeasures for the government to implement.  相似文献   
29.
Using data on household consumer durables from the Asian Barometer Survey, this paper examines the evolution of inequality, poverty and welfare in six countries of South East Asia: Cambodia, Indonesia, Malaysia, the Philippines, Thailand and Vietnam. We start by deriving the most common order of acquisition of these durables, using first an algorithm proposed by Paroush (1965), and then Item Response Theory. We also compute the frequency distribution of the number of durables owned by households. We then use these results to compute inequality, poverty and achievement or welfare indices adapted to the case of ordinal variables.Our empirical results confirm the existence of an order of acquisition. The results show that inequality was higher in Cambodia, Indonesia and the Philippines and lower in Vietnam, Thailand and Malaysia. A similar classification of countries was obtained when computing multidimensional poverty indices.Finally, using the welfare or achievement index recently introduced by Apouey et al. (2019), we found that welfare was generally higher in Vietnam, Thailand and Malaysia and lower in Cambodia, Indonesia and the Philippines.  相似文献   
30.
We study a bilateral negotiation set-up where, at a bargaining impasse, the disadvantaged party chooses whether to escalate the conflict or not. Escalation is costly for both parties, and it results in a random draw of the winner of the escalated conflict. We derive the behavioral predictions of a simple social utility function, which is convex in disadvantageous inequality, thus connecting the inequity aversion and the prospect theory models. Our causal laboratory evidence is, to a large extent, consistent with the predicted effects. Among other things, the model predicts that the escalation rate is higher when escalation outcomes are riskier, and that the disagreement rate is lower when the cost of escalating the conflict is higher.  相似文献   
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