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71.
One of the most crucial constraints in operation of electrical power supply systems is the permanent balance between generation and load. Reserve power is held ready to be able to keep this balance also in case of the occurrence of unpredictable events like power plant outages or inevitable deviations of power injections from their predicted values. At this, the allocation of operating reserves is in the field of conflict between level of reliability and cost effectiveness. The amount of reserve generation capacity required in a control area heavily depends on prediction quality which constitutes the need for high quality predictions. This article is about the influence of prediction quality on the amount of reserve generation capacity required in a control area. The algorithms for the assessment of required reserve generation capacity known from literature use the variation calculus technique to account for the aforementioned unpredictable events and prediction errors. In this article, an extension to a convolution-based method is presented in which the uncertainties of the predictions are expressed using intervals. Each parameter is represented by an independent dimension, assuming statistical independence among them. This allows the distinct analysis of each parameter’s influence on the amount of required reserve generation capacity. In addition, two methods for the visualization of the multi-dimensional results are presented, allowing a comprehensive analysis of the parameters’ influences. Standard distribution functions are used to represent the parameters for the simulation and the results are shown as probability density functions of possible imbalances. Based on forecasts of the development of conventional power plants and regenerative generation in the years 2020, 2030 and 2040, the required control power of the future German transmission system is calculated. Influences and dependencies are identified with the extended convolution-based method.  相似文献   
72.
Generally valid scientific explanations of observable social phenomena are still hardly available. By applying philosophical insights generated by Quine and derived from semiotics to social research methodology three kinds of context dependencies accompanying theory formation within social science are identified. The third context dependency is mostly not attended in theory formation about social phenomena thereby producing a ``connotation fallacy', which leaves almost all social theories undetermined and fallible. These context dependencies should be taken into account in the research design and be tested for using statistical criteria comprising a new methodology presented in this article.  相似文献   
73.
Previous studies already established the idea of a partnership in which HR professionals and line managers share an organisation’s HRM responsibility. Yet, this relationship is often plagued by conflicts and other obstacles. As such, a perceptual discrepancy is likely to exist between both parties on the degree of HR devolution, which may eventually lead to bad performance. Using survey data, we empirically analyse which factors may explain a perceptual discrepancy between HR professionals and line managers on the latter group’s role in HRM. Results show that the HR-line discrepancy on the degree of HR devolution is rooted in differences in perception on several other factors, including organisational support, (personnel) red tape, the line’s individual capacity and age. Overall, though, it is a matter of understanding both HR’s expectations and the line’s experiences in all aspects of their partnership.  相似文献   
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75.
The business process management literature describes a multitude of approaches (e.g. imperative, declarative or event-driven) that each result in a different mix of process flexibility, compliance, effectiveness and efficiency. Although the use of a single approach over the process lifecycle is often assumed, transitions between approaches at different phases in the process lifecycle may also be considered. This article explores several business process strategies by analysing the approaches at different phases in the process lifecycle as well as the various transitions.  相似文献   
76.
In this paper, the firms within two pairs of complementors decide whether to merge and eventually bundle their products. Depending on the competitive pressure in the market, either the firms within both pairs merge, with or without bundling, or only one pair merges and bundles, whereas the other one remains independent. The latter case can be harmful for consumers as overall prices surge. We also consider the case where a pair moves before the other. Interestingly, we find a parametric region where the first movers merge, but refrain from bundling, to not induce rivals to merge as well. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
77.
This article, based on a postal survey and qualitative interview‐based research, examines the relationship between major private recruitment bureaux and their clients in the UK, with particular attention to the recruitment and selection of temporary workers. The private recruitment industry is growing and large bureaux are seeking closer partnership arrangements with clients. Contracts for labour services are being developed on a 'preferred' supplier basis – similar in type to the approach taken for the purchase or supply of goods or components. However, formal preferred supplier contracts with temporary work bureaux were used by only a minority of clients, usually larger organisations or those having projects or workplaces with high volume demand. While such bureaux seek models of relational contracting or partnering, many clients prefer less fully engaged or 'semi‐distanced' relations facilitated by the informal dimensions of inter‐organisational contacts.  相似文献   
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79.
We consider the theory of R-estimation of the regression parameters of a multiple regression models with measurement errors. Using the standard linear rank statistics, R-estimators are defined and their asymptotic properties are studied as robust alternatives to the least squares estimator. This paper fills the gap of the rank theory for the estimation of regression parameters with measurement error models. Some simulation results are presented to show the effectiveness of the R-estimators.  相似文献   
80.
With the globalization of trade and the increased understanding of transboundary problems such as global climate change, the need for understanding the consequences of technological change has never been higher. Institutional arrangements necessary to assess these changes and make decision makers aware of the consequences have not necessarily adapted to these world conditions. In response to this leading technology assessment and forecasting institutions formed an international association of technology assessment and forecasting institutions to assist in the diffusion of technology assessment in the decision-making process. This paper discusses the origins of the International Association of Technology Assessment and Forecasting Institutions (IATAFI) and the goals and vision for the organization. The following articles represent some of the topics discussed at the first IATAFI conference in Bergen, Norway in May 1994.  相似文献   
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