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51.
The aim of this paper is to analyse and compare injuries and injury sources in pedestrian and bicyclist non-fatal real-life frontal passengercar crashes, considering in what way pedestrian injury mitigation systems also might be adequate for bicyclists. Data from 203 non-fatal vehicle-to-pedestrian and vehicle-to-bicyclist crashes from 1997 through 2006 in a city in northern Sweden were analysed by use of the hospitals injury data base in addition to interviews with the injured. In vehicle-to-pedestrian crashes (n = 103) head and neck injuries were in general due to hitting the windscreen frame, while in vehicle-to-bicycle crashes (n = 100) head and neck injuries were typically sustained by ground impact. Abdominal, pelvic and thoracic injuries in pedestrians and thoracic injuries in bicyclists were in general caused by impacting the bonnet. In vehicle-to-pedestrian crashes, energy reducing airbags at critical impact points with low yielding ability on the car, as the bonnet and the windscreen frame, might reduce injuries. As vehicle-to-bicyclist crashes occurred mostly in good lighting conditions and visibility and the ground impact causing almost four times as many injuries as an impact to the different regions of the car, crash avoidance systems as well as separating bicyclists from motor traffic, may contribute to mitigate these injuries.  相似文献   
52.
We investigate optimal abatement strategies for cumulative and interacting pollutants. We show that different decay rates can cause non-monotonic behavior in the optimal paths of emissions, the aggregate level of pollution, and even the relative optimal price for emissions. This contrasts strikingly with the case of a single pollutant. The results are illustrated by numerical simulations, first for instructive fictitious and second for more realistic parameters mimicking the greenhouse problem. The results add to the skepticism existing about whether the concept of global warming potential is a useful indicator for the optimal relative abatement of different GHGs over time. In fact, we show that a constant index suitable for comparing dynamically different pollutants with respect to their economic harmfulness does not exist.  相似文献   
53.
In the analysis of stated preferences studies, it is often assumed that protesting is a discretely measured item only occurring among those who are not willing to pay. However, various studies have recently shown that protest beliefs are as well held by respondents who state a positive willingness to pay (WTP). Using latent class (LC) models, we investigate the extent of heterogeneity with respect to protest beliefs among all respondents of two contingent valuation studies. The advantage of LC models is that classes of individuals are endogenously identified and no selection bias is introduced by ad hoc definitions of protesters. Further we investigate whether it is possible to identify a class of non‐protesters. Finding a group of pure non‐protesters could indicate how strongly stated WTP in the whole sample is affected by protest beliefs. For both samples, we find a class with strong protest beliefs but no pure non‐protest class. Overall, our results suggest that LC models might not be the first choice to determine unbiased WTP measures, but they provide valuable insights into the degree of protesting expressed by different groups and corresponding determinants of group membership.  相似文献   
54.
Due to the age structure of the German generation system and the nuclear phase out, a significant amount of older power plants will be substituted during the coming years by newly built generation units. Such projects are frequently realized as combined gas and steam turbines, so-called Combined Cycle Power Plants or Combined Cycle Gas Turbines (CCGT). These power plants, mostly fired by natural gas, possess high efficiency factors combined with low specific CO2-emissions compared to other conventional power plants, e.g. fired by coal and moreover provide a high operational flexibility. As they represent a combination of several thermal processes, their generation planning and optimized dispatch are more demanding than those of existing steam or gas turbines. Therefore, a new formulation of the unit commitment problem is required, including all relevant technical and economic restrictions for scheduling CCGT. In this paper, the relevant characteristics of the different types of CCGT are analyzed. This especially includes part load efficiency and the permitted modes of operation. For modeling of these characteristics and for optimizing the CCGT dispatch, a decomposition approach as well as a linearized closed-loop formulation is introduced. In the decomposition the optimization problem is split into sub problems, which can be solved with specialized algorithms. As the recombination of these sub problems may result in a limitation of the overall solution quality, the closed-loop approach considers the entire problem, but has to linearize the formulation to ensure solvability. By applying both methods on an exemplary case the advantages and shortcomings of both approaches can be analyzed in detail. This comprises model accuracy, overall solution quality and a detailed schedule analysis and comparison. The paper??s results will also show the deviations caused by the different modeling approaches. Finally, the results show the added value of the adequate modeling of combined cycle power plants towards gas or steam turbines.  相似文献   
55.
Organizations routinely make choices when addressing conflicting stakes of their stakeholders. As stakeholder theory continues to mature, scholars continue to seek ways to make it more usable (and relevant), yet proponents continue to debate its legitimacy. Various scholarly attempts to ground stakeholder theory (empirically, instrumentally, or normatively) have not narrowed down this debate. We draw from the work of Juergen Habermas to theoretically advance stakeholder theory, and to provide practical examples to illustrate our approach. Specifically, we apply Habermas’ language-pragmatic approach (which places strong emphasis on dialogue, participation, and procedural justice) to extend stakeholder theory by advancing seven sets of normative axioms (10 axioms in total). We conclude that a deliberative approach, with its focus on the conditions of legitimation and deliberative democracy, has the potential to become a cornerstone of stakeholder theory. The need for global stakeholder discourse and its internalization in corporate structures and institutions is exemplified by a multitude of CSR and stakeholder initiatives that have mushroomed in response to global risk scenarios such as climate change, nuclear warfare, or terrorism. Further research may help to build a functioning global governance system in order to provide guidance for management in the 21st century.  相似文献   
56.
In many domains, consumers must deal with an increasing number of choices—spanning where, when, what, and how many items to buy; how many and which options to consider; and how best to weigh the pros and cons of these options. This paper considers how consumer and managerial goals and the ensuing tradeoffs affect the optimal design of assortments in order to help enhance our understanding of assortment choice, identify issues that merit particular attention, review some of the recent research in pertinent areas, and suggest directions for future research.  相似文献   
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58.
This paper investigates conceptually how new Greenfield subsidiaries develop relationships over time. We focus our analysis on the earliest start-up stage of new Greenfield subsidiaries, and on the dynamics of relationships development with five different groups of actors within the MNC and the local environment of the new Greenfield. We argue that relationship strength, or the intensity of interaction and resource exchange, depends on the new Greenfield's degree of dependence or interdependence within these relationships and develop propositions based on institutional theory, resource dependency theory and network approaches. In the concluding sections we suggest directions for future work to enhance understanding of the dynamics of relationship management in new Greenfield expansions.  相似文献   
59.
Parks provide benefits for the physical, psychological, and social well-being of residents in neighborhood environments. Multilevel logistic regression was used to examine associations between neighborhood- and individual-level characteristics and the lack of park use in Montreal. Data on park use were collected from 787 adults residing in 299 different neighborhoods. Results found that older adults who lived in areas with a younger age composition were more likely not to use their nearby parks as compared to older adults living in areas with an older age composition. Forms of social participation were also important for the park use of older adults. Public policies should consider targeting aspects of the social environment to improve neighborhood park use.  相似文献   
60.
This paper explores interorganizational cost management (IOCM) practices in the exchange process. IOCM can be defined as buyers’ and suppliers’ coordinated efforts to reduce costs. Past research has primarily argued that such practices depend on component characteristics, relationship characteristics, and characteristics of the transaction. Based on a study of three buyer–supplier relationships, this article also finds variations in IOCM practices between six main activities in the exchange process. In this process, the supplier's management accounting is found to be more important than recognized by prior research. The deepest collaboration around IOCM issues and the greatest joint use of suppliers’ management accounting in the three cases typically occurs in earlier activities in the exchange process, including supplier selection, joint product design and joint manufacturing process development. In later activities in the process, during full-speed production as well as in product and manufacturing process redesign, suppliers’ managerial accounting plays a lesser role in our study.  相似文献   
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