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1.
Based on the day-night PM2.5 difference of the nearest atmospheric monitoring points to measure whether there is illegal emission, this paper explores the impact of environmental protection officials' tenure (EPLT) on illegal emissions. The results show that there is a positive correlation between EPLT and illegal emissions. Stable EPLT can reduce illegal emissions by increasing environmental information disclosure and environmental subsidies. It can increase illegal emissions by weakening public pollution reporting and media supervision, environmental law enforcement and promoting corruption. In addition, EPLT can increase illegal emissions as EPLT is less than 3.55 years, while EPLT can increase illegal emissions as EPLT exceeds 6.21 years. Further, when mayor's tenure and EPLT are both stable, the promotion effect of EPLT on illegal emission is stronger. Stable company director's tenure can also aggravate the promotion effect of EPLT on illegal emissions.  相似文献   
2.
This paper aims to analyze and understand the impact of the corona virus disease (COVID-19) on aviation and also the role aviation played in the spread of COVID-19, by reviewing the recent scientific literature. We have collected 110 papers on the subject published in the year 2020 and grouped them according to their major application domain, leading to the following categories: Analysis of the global air transportation system during COVID-19, the impacts on the passenger-centric flight experience, and the long-term impacts on broad aviation. Based on the aggregated reported findings in the literature, this paper concludes with a set of recommendations for future scientific directions; hopefully helping aviation to prepare for a post-COVID-19 world.  相似文献   
3.
Fossil-fuel burning transportation methods significantly contribute to air pollution. During the COVID-19 pandemic, South Korea experienced a 10-20% decline in commuting flows, even without government-mandated stay-at-home orders. This paper quantifies the impact that decreased commuting flows have on PM2.5, PM10, NO2, CO, and SO2, using municipality level commuting data. We find that a 1% decrease in commuting flows decreases air pollutants by 0.08-0.17%, after controlling for seasonality and time-varying local production. The effect was higher in regions with high initial pollution, and people recognized air quality improvements. These results emphasize the importance of encouraging cleaner transportation methods after the pandemic.  相似文献   
4.
The outbreak of the COVID-19 pandemic has drastically disrupted the air cargo industry. This disruption has taken many directions, one of which is the demand imbalance which occurs due to the sudden change in the cargo capacity, as well as demand. Therefore, the random change leads to excessive demand in some routes (hot-selling routes), while some other routes suffer from a big shortage of demand (underutilized routes). Routes are substitutable when there are several adjacent airports in the Origin & Destination (O&D) market. In this market, demand imbalance between substitutable routes occurs because of the above reasons. To tackle the demand imbalance problem, a novel model is introduced to estimate the quantity combinations which maintains the balance between underutilized and hot-selling routes. This model is a variant of the classic Cournot model which captures different quantity scenarios in the form of the best response for each route compared to the other. We then cultivate the model by integrating the Puppet Cournot game with the quantity discount policy. The quantity discount policy is an incentive which motivates the freight forwarders to increase their orders in the underutilized routes. After conducting numerical experiments, the results reveal that the profit can increase up to 25% by using the quantity discount. However, the quantity discount model is only applicable when the profit increase in the hot-selling route is greater than the profit decrease in the underutilized route.  相似文献   
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6.
Drawing on social exchange and push–pull–mooring theories, this paper develops a taxonomy-based preferred-customer model for B2B air express markets. Our model extends the conventional bilateral customer-supplier relationship perspective of customer portfolio management to include competition effects for more comprehensive (trilateral) strategic decision making. Based on this unified framework, our a survey of 180 customers of air cargo express carriers identifies three distinctive groups of preferred customers. In addition to the effect of competitors on air express carriers’ prioritization of customers, which is further complicated by a satisfaction paradox and spurious loyalty, we further establish classification indicators for differentiating preferred from non-preferred customers. Notably, although commonly used in practice, we find sales volumes to be ineffective for that purpose.  相似文献   
7.
This research focuses on understanding the air taxi operations to determine the number of air taxis required to fulfill the demand for urban air mobility in New York City (NYC). We leverage the Define, Measure, Analyze, Design, and Verify (DMADV) framework and integrate it with the systems simulation approach. Upon investigation, we find that all the parameters linearly impact the vehicle utilization, while other measures are robust, specifically with respect to the seating capacity. It is also recommended to operate initially with 70 air taxis in NYC to achieve a trade-off between customer wait time and vehicle utilization. The proposed approach can act as a recommender system for air taxi companies.  相似文献   
8.
The coronavirus pandemic has had a devastating impact on the demand for air transport. One passenger segment that has received relatively little attention is ageing passengers (defined as aged 65+), in spite of the fact that this group has been disproportionately affected by COVID-19, and in recent years has been viewed as a potential growth market. Therefore, the aim of this brief paper is to analyse the attitudes of ageing passengers by assessing air travel plans in the next 12 months, examining the factors influencing future flying decisions, and investigating the impact of the coronavirus pandemic on perceived risks and experiences associated with flying. The findings show that over 60% of ageing passengers are planning to travel by air in the next 12 months, although the nature of their trips may change. Factors such as flexible ticket booking and quarantine rules do not appear to be key drivers affecting travel decisions and within the different stages of the air journey, getting to/from the airport is perceived as the safest stage. The findings suggest that there are various COVID-19 implications for airlines and airports serving this market segment, ranging from the use of self-service technology, the generation of commercial/ancillary revenues and the design of surface access policies.  相似文献   
9.
This paper discusses the situation of China's air cargo sector facing the COVID-19 pandemic. Based on the expectation that it can go out of recession more easily than China's air passenger sector, this paper analyzes four aspects that are favorable and unfavorable for its further development: (1) strengths (China's sustainable economic basis and proliferating cargo suppliers), (2) weaknesses (insufficient cargo capacity and less business internationalization), (3) opportunities (top authority support, rising e-commerce demand, and new technological momentum), and (4) challenges (uncertain trade environment and increasing profitability pressure). Then this paper suggests strategies for China's air cargo suppliers to adapt to the pandemic.  相似文献   
10.
Air transport deregulation has lead to an increase of air traffic, together with a reduction of air fares. Air fare reduction has narrowed operational margins of airlines, bringing financial and employment instability. This has brought airlines to pay increasing attention to flying costs reduction. Two important components of flying costs airlines can try to cut modifying the planned flight are en route charges and operational costs. We rely on Demand Data Repository (DDR2) data to calculate deviations from planned flight trajectories to analyse the extent to what airlines try to cut operational costs making shorter flights than planned if possible, and cut en route charges providing a planned flight with lower en route charges than the planned flight. Our findings show that there is no generalised strategy among airlines to reduce en-route charges asking for deviations of the planned route. On the other hand, airlines are achieving savings of operational costs regularly. Higher savings per nautical mile are obtained in night flights, with longer planned distance and operated by low cost carriers.  相似文献   
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