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621.
As companies continue to utilize co-production (customer participation in product or service creation) strategies with consumers, academic researchers have expanded their study on issues related to co-production. However, research has been scant on the issue of control in such situations. The underlying belief in increasing customer participation and involvement is it increases customers’ perceived control, thereby enhancing their experience and outcomes; this belief creates the necessity for further examination of control in co-production environments. This study examines consumers’ affective responses to differing levels of three types of control (cognitive, behavioral, and decisional) in low and high co-production conditions. Using two experimental contexts and one survey study, the results show increasing cognitive control will increase affect when co-production is low. Behavioral control can negatively or positively influence affect depending on specific situational contexts and perceptions of customization in low co-production conditions. Lastly, decisional control is found to be an important positive contributor to affect regardless of co-production level. Theoretical and practical implications are discussed.  相似文献   
622.
Since the 1980 Education Act, school caterers have been operating within a commercial context and therefore can only provide the foods that they know that children will eat. At the same time, nutritionists have been concerned that the greater degree of choice that children now have at lunchtime is resulting in the more frequent consumption of meals of poor nutritional quality. A knowledge of children's food preferences, the factors influencing them, and their perceptions of the healthiness of foods is needed if school caterers and those involved in nutrition education are to work together to help children choose a nutritionally balanced meal. This paper reports on children's perceptions of the healthiness or otherwise of foods commonly served at school lunches and the reasons for these perceptions. Children's knowledge of the sources of nutrients, their understanding of the relationship between food and health, and how their perceptions of healthiness relate to their preferences for the foods are also explored. The nutritional implications of food choices made by primary school children on the basis of preference rather than healthiness are examined. One hundred and twenty three children aged between nine and eleven from 14 different primary schools in SouthEast England took part. Using photographs of foods commonly served at school lunches, the children were asked to rank the foods in order of preference and then according to their perceptions of the healthiness of the foods and give their reasons in each case. The rankings were analysed numerically and the Wilcoxon's pairs signed rank test was used to determine the significance of the difference. The qualitative data on the reasons given for the rankings were analysed by assigning them to categories. The children were also asked which foods they would choose for the meal that they would be most likely to eat, and which ones for the meal that they thought would be the most healthy. The nutritional value of the two sets of meals were determined and compared. A student T- test was used to determine the significance of any difference between the two sets of meals.It was found that the children had a clear perception of the healthiness or otherwise of the foods. However, understanding of the relationship between foods or nutrients and health was only occasionally evident, as was the idea of moderation or balance. Some children perceived healthiness as the absence of fat while others saw it in terms of the presence of vitamins. It was also found that there was a strongly inverse relationship between children's perceptions of the healthiness of foods and their preferences for them. It was found that while the foods chosen for the ‘healthy’ meal were chosen least frequently for the ‘preferred’ meal, there was no significant difference between the percentage of energy provided by fat in the two sets of meals. However the ‘preferred’ meals did in fact provide a significantly higher percentage of the energy as starch, as well as containing greater amounts of some micronutrients. In other respects the ‘healthy’ meals were indeed ‘healthier’, in that they provided greater amounts per megajoule of some important nutrients.It was concluded that teaching about food in primary schools needs to focus on helping children of this age make balanced food choices. It was suggested that the ‘tilted plate’ model, adapted to use foods that children frequently eat and enjoy, could be the basis of such teaching. Such a model could also be used to help caterers plan menus and as the basis of co-operation between nutrition educators and caterers.  相似文献   
623.
Altering production systems and land management of tree crops is a costly, disruptive and ultimately irreversible decision. Using traditional valuation methods to appraise long‐term land management outcomes ignores the full impact of irreversible or delayed decisions. We employ a variant of the real options decision process to examine uncertainties around climatic effects on macadamia growers and the explicit decision to adapt via cultivar replacement. We examine the trade‐offs between the timing of the decision to replace macadamia cultivars by considering both the value of flexibility as well as the value of new information that can be used to resolve uncertainty. We compare the relative responses that generate the most value for growers across four geographical locations. We show that simple switching decisions using traditional valuation methods are found to be suboptimal and initiate poor decisions, potentially undermining adaptation efforts. As the rate of orchard degradation increases, the need to transition to higher‐yielding cultivars becomes greater, especially for Hawaii, California and Australia where gross margins are leaner. Investment decisions are thus highly dependent on both local conditions and the economic structure of existing production systems.  相似文献   
624.
Over 90% of exchange trading on crypto options has always been on the Deribit platform. This centralized crypto exchange only lists inverse products because they do not accept fiat currency. Likewise, other major crypto options platforms only list crypto–stablecoin trading pairs in so-called direct options, which are similar to the standard crypto options listed by the CME except the US dollar is replaced by a stablecoin version. Until now a clear mathematical exposition of these products has been lacking. We discuss the sources of market incompleteness in direct and inverse options and compare their pricing and hedging characteristics. Then we discuss the useful applications of currency protected “quanto” direct and inverse options for fiat-based traders and describe their pricing and hedging characteristics, all in the Black–Scholes setting.  相似文献   
625.
Journal of Productivity Analysis - The Debreu–Farrell measure of technical efficiency is widely used to benchmark firm performance. A limitation of this measure is that it is orientation...  相似文献   
626.
We use difference-in-differences approaches and parcel-level data from Minneapolis to estimate the effects of light rail on land use change using alternate definitions of treatment area. Results using circular buffers corroborate previous findings that light rail has virtually no effect on land use change in our study area. In contrast, light rail increases the likelihood of land use change along arterial streets that cross the line at station areas. To accurately model the effects of public transit projects on urban land use, one must consider how potential riders access station areas, rather than assuming accessibility improves radially around a station.  相似文献   
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