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361.
This paper develops three game-theoretical models to analyze shipping competition between two carriers in a new emerging liner container shipping market. The behavior of each carrier is characterized by an optimization model with the objective to maximize his payoff by setting optimal freight rate and shipping deployment (a combination of service frequency and ship capacity setting). The market share for each carrier is determined by the Logit-based discrete choice model. Three competitive game strategic interactions are further investigated, namely, Nash game, Stackelberg game and deterrence by taking account of the economies of scale of the ship capacity settings. Three corresponding competition models with discrete pure strategy are formulated as the variables in shipment deployment are indivisible and the pricing adjustment is step-wise in practice. A ɛ -approximate equilibrium and related numerical solution algorithm are proposed to analyze the effect of Nash equilibrium. Finally, the developed models are numerically evaluated by a case study. The case study shows that, with increasing container demand in the market, expanding ship capacity setting is preferable due to its low marginal cost. Furthermore, Stackelberg equilibrium is a prevailing strategy in most market situations since it makes players attain more benefits from the accommodating market. Moreover, the deterrence effects largely depend on the deterrence objective. An aggressive deterrence strategy may make potential monopolist suffer large benefit loss and an easing strategy has little deterrence effect. 相似文献
362.
In view of the ongoing discussions concerning the possible designation of the Mediterranean Sea as a Sulphur Emission Control Area (SECA), a modal split model was applied to a case involving the transportation of consolidated cargoes between Thessaloniki, Greece and industrial hubs of northern Germany. A road-only option was assessed against a combined-transport route involving a ferry (Greece–Italy) and a truck-on-train (Italy–Austria) service. The logit model used considers two variables as determinants of the modal selection: transport cost and time. The data are derived from interviews with a small transport service provider, typical for Greece, and are based on actual trips made (revealed preferences). The results predict that the designation of the Mediterranean as a SECA will cause a modal shift in favour of the road-only route by 5.2%, which under certain assumptions can reach 17.1%. However, the environmental implications of the resulting modal choices, calculated through the EcoTransIT World web based tool, are positive in relation to all emissions examined. This is attributed to the longer distance of the combined-transport option in comparison to the road-only one and, the poor environmental performance of the Ro-Pax vessels basically due to the need to maintain a relatively high speed. 相似文献
363.
甄远 《南通航运职业技术学院学报》2014,(2):81-86
长江口海运历史绵远,优势独具,这才成为下西洋船队的航海出发地。夏原吉治水,"制淞通娄",娄江口水势骤增,造就了刘家港,而郑和下西洋远航从这里始发也取得了丰厚的收获。 相似文献
364.
苏州河是上海市建设"卓越的全球城市"的代表性空间和标志性载体,具有丰富的人文资源和滨水景观.《苏州河沿岸地区建设规划》(2018-2035)将外环外郊区段定位为生态廊道,实现生态保育和休闲游憩功能.结合近年来苏州河(青浦区)堤防专项维修工程中的经验,分析苏州河郊区段存在的主要问题,并提出对策和建议. 相似文献
365.
文中通过分析尹公洲航段的复杂环境及航路航法,分析造成尹公洲航段事故多发的主要原因并探讨解决的方法。 相似文献
366.
贵州乌江大桥是国内首次采用预应力钢纤维混凝土(P.F.C)主梁建造的吊拉结构组合桥.结合乌江大桥运营期间的病害调查和检测结果,采用有限元计算分析方法对该桥主要构件的承载能力及工作性能进行评估,初步分析病害成因并给出初步的建议措施. 相似文献
367.
368.
The key features of the western Galician shelf hydrography and dynamics are analyzed on a solid statistical and experimental basis. The results allowed us to gather together information dispersed in previous oceanographic works of the region. Empirical orthogonal functions analysis and a canonical correlation analysis were applied to a high-resolution dataset collected from 47 surveys done on a weekly frequency from May 2001 to May 2002. The main results of these analyses are summarized bellow. Salinity, temperature and the meridional component of the residual current are correlated with the relevant local forcings (the meridional coastal wind component and the continental run-off) and with a remote forcing (the meridional temperature gradient at latitude 37°N). About 80% of the salinity and temperature total variability over the shelf, and 37% of the residual meridional current total variability are explained by two EOFs for each variable. Up to 22% of the temperature total variability and 14% of the residual meridional current total variability is devoted to the set up of cross-shore gradients of the thermohaline properties caused by the wind-induced Ekman transport. Up to 11% and 10%, respectively, is related to the variability of the meridional temperature gradient at the Western Iberian Winter Front. About 30% of the temperature total variability can be explained by the development and erosion of the seasonal thermocline and by the seasonal variability of the thermohaline properties of the central waters. This thermocline presented unexpected low salinity values due to the trapping during spring and summer of the high continental inputs from the River Miño recorded in 2001. The low salinity plumes can be traced on the Galician shelf during almost all the annual cycle; they tend to be extended throughout the entire water column under downwelling conditions and concentrate in the surface layer when upwelling favourable winds blow. Our evidences point to the meridional temperature gradient acting as an important controlling factor of the central waters thermohaline properties and in the development and decay of the Iberian Poleward Current. 相似文献
369.
370.
ABSTRACTThis paper investigates the cyclical nature of container shipping market represented by a containerized freight index and proposes a predictive cyclical model of the market. In contrast to the traditional spectral analysis (univariate), system dynamics reflect the drivers of the market in both supply and demand side, and therefore, it is a multi-variate system equilibrium approach consisting of various causal spillovers from sub-components of the market. This study is the first to analyze the cycle of container market using system dynamics. By utilizing system dynamics cyclicality approach, one-step ahead predictions are generated for monthly containerized freight index and compared to conventional benchmarks for post-sample validation. Our study can also help policymakers and shipping liners for better management and invest timing of container ship. 相似文献