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91.
The need to measure and evaluate transit system performance has led to the development of numerous performance indicators. However, depending upon the indicator, we oftentimes reach different conclusions regarding transit system performance. The research reported in this paper uses factor analytic methods to generate a set of underlying attributes (factors) that capture the performance of public transit systems in Indiana. Similar to what is reported in the literature, this study finds three attributes that best describe transit system performance: efficiency, effectiveness, and overall performance. Based upon systemsÕ factor scores, the study finds that systems scoring highly on one attribute generally perform well on the remaining attributes. Further, there is an inverse relationship between system performance and subsidies, a finding that supports performance based subsidy allocations. 相似文献
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93.
水下混凝土灌注是钻孔灌注桩施工中易出现各种质量事故的一项重要隐蔽工程,为避免给工程带来隐患,应采取合理有效的措施对水下混凝土施工质量事故进行防治. 相似文献
94.
国务院在"关于加强地质工作的决定"中明确规定:"对发现有商业价值的探矿权人,依法维护其继续勘查、探矿权转让、采矿权取得等权利",这无疑是对地质工作的肯定和再发展注入了生机,但是随之而来的各种管理、经营及廉政范畴以外的问题也应用而生,为了顺利开展工作,效能检察此时就显得非常重要了。本文试从以下几个方面探讨一下效能监察与矿产开发的关系。 相似文献
95.
All developments on air pollution by ships are fairly recent. Annex VI of the international Marpol-convention, regulating
the emissions of CFCs, Halons, Volatile Organic Compounds (VOCs) from cargoes, emissions from incinerators and exhaust gas
emissions from engines (NOx and SOx) entered into force in May 2005. The International Maritime Organization is currently discussing an upgrade of the air pollution
issues covered by Annex VI and some that are not in Annex VI, such as greenhouse gas emissions. CO2 is the most important greenhouse gas emitted by ship. Fuel consumption by the world merchant fleet is expected to grow to
between 250–300 million tons per year with corresponding CO2 emissions of 800–960 million tons per year. In Western Europe land based measures have reduced sulphur emissions substantially,
leaving shipping as an important remaining source of these emissions. Average sulphur content of heavy fuel oils is 3%, with
a limit of 4.5% imposed by Annex VI. Both the Baltic- and the North Sea have the status of SOx emission control area, limiting sulphur content to 1.5%. 相似文献
96.
The nature of the global economy is one of dynamic change. Shipping is a service industry with its demand related to changes in international trade levels and patterns. As a consequence shipping is subject to sometimes unpredictable swings in demand so that the operator is required to make strategic planning decisions while navigating through boom or bust environments. While boom economies generate rising freight rates which are welcomed and encourage investment, ship operators may also have to face falling freight demand and declining freight rates that may have significant impact on profitability, often falling to uneconomic levels for extended periods. In such a period of uncertainty and declining profitability management will make operational decisions to reduce costs. However, shipping lines operate in a market environment so any decisions made to rationalize the trade may have significant long-term competitive implications. For example, traditional micro economic theory might suggest that the prudent strategy to adopt would be to close down the operation and reopen when the market conditions improve. In a world of certainty or when costs of taking this action are zero, this would be a valid strategy. However, because of fear of competitors taking up a line's market share if the shipping company exits, even temporarily, this strategy cannot be valued simply in terms of shut-down and start-up costs. A further consideration is the fact that standard capital budgeting techniques, such as Net Present Value (NPV), cannot incorporate the flexibility to respond to new information and strategic responses explicitly into their investment analysis. This paper will demonstrate the use of Real Option Analysis (ROA) to provide guidelines for decisions about closing operations in adverse market conditions. 相似文献
97.
98.
J. M. Weslawski J. Wiktor J. Koszteyn M. Zajaczkowski P. Wieczorek L. Kotwicki 《Journal of Marine Systems》1997,10(1-4)
Multidisciplinary, marine ecological observations were conducted at the shallow water edge of the Northeast Water in June, 1993. Although variable in size and shape, a small polynya was constantly present at Eskimonaes, at the fast-ice edge of Ingolfsfjord. A shallow stratified layer developed at the water sufface at negative water and air temperatures—an effect of sea ice melting in cold water early in the season. Nutrients were recorded in considerable quantities, although by mid July NO3 had become depleted. The chlorophyll and phytoplankton maxima at 8–12 m depth had peak values of 2 mg chl a m−3, typical for Arctic algal blooms. The phytoplankton included over 90 species and was dominated by the Fragillariopsis group. Zooplankton was poor in biomass and density, but over 23 taxa were found, with the copepods Oithona similis and Pseudocalanus acuspes being numerically dominant. Sedimentation was approximately 0.2 g dry weight m−2 d−1 and suspended matter concentrations ranged from 4 to 19 mg l−1. The benthos was represented by hard bottom forms only, with a surprisingly dense cover of macrophytes. Juvenile sea urchins (Strongylocentrotus droebachiensis), brittle stars (Ophiocten sericeum) and amphipods were dominant. Higher trophic levels were represented by benthic feeders, such as eiders and walruses. The area observed was more similar to high Arctic fjord ecosystems than to the offshore central Northeast Water polynya. 相似文献
99.
Container line supply chains, based on a near-frictionless international transport belief, have contributed to economic prosperity
and also rendered themselves uniquely vulnerable to various risks. 9/11 terrorists attacks, the lock-out of American West
Ports and the global breakout of SARS disease have gradually shown that a) the safety and reliability in the chains are facing
an unprecedented challenge and b) traditional engineeringbased risk assessment methods are inadequate to deal with the threats
from variational environments, especially in the era of terrorism rampancy. The purpose of this paper is, therefore, to develop
a conceptual risk assessment model for container line supply chains based on a modified Formal Safety Assessment (FSA) methodology
that takes risks from vulnerability rather than only hazards into account. It gives particular emphasis on the analysis of
the threats with a high level of uncertainty from both safety and economic viewpoints. The advantages of the vulnerability-based
risk analysis approach to the hazard-based one are clarified and both engineering-based and managerial risk assessments are
also discussed. 相似文献
100.