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Harald Wagner 《隧道建设》2012,32(2):139-141
合同对地下工程非常重要。主要阐述地下工程的合同编制阶段、合同含义和项目组织。首先介绍合同模式及合同的主要构成,然后详细阐述合同编制中需要重点关注的几个方面,如不良地质应对、风险控制、施工前采取的措施、风险规避措施、工程勘探质量和施工前、施工中采取的勘探措施等。  相似文献   
2.

In intermodal logistics, combined transport operators and railway companies are engaged in the development of efficient block train concepts. The proportion of transport using single railway wagons is decreasing because of its poor time-quality ratio. In future, transport services will be focussed on industrial zones and large cities that offer the transport volumes required for direct train operation. In this regard, it will become more difficult for regions with smaller load volumes to be integrated into a combined transport network. In order to confront this trend, new concepts for bundling transport volumes have to be developed. One such concept is the 'mega hub'. The core idea is to interchange load units between several block trains during a short stop at an intermodal terminal. The paper provides an overview of the operating concept of the mega hub and the opportunities for intermodal transport operators.  相似文献   
3.
Abstract

Shifting cargo from land‐based modes to maritime transport has been a prioritized policy in many policy papers to make transport more environmental friendly. Traditional calculations of emissions per transport capacity unit have supported this. However, maritime transport may stand to loose its good environmental reputation in comparison to road transport due to (1) the sluggish processes in maritime environmental policies and the low ambition level of current regulations, (2) the much higher focus on improving the environmental efficiency of the road haulage industry, (3) the much longer economic life of vessels compared to trucks, and (4) focus on faster vessels that increase the average fuel consumption of the sea transport alternative. Through a realistic case study, the energy efficiency and emissions of alternative multimodal transport chains is presented to illustrate these points.  相似文献   
4.
The first railway package is being recast by the legislative bodies of the European Union. One point of departure in this paper is how Swedish agencies treat issues concerning marginal cost based charges, financing charges and allocation of scarce capacity and it discusses these issues from a welfare point of view, partly by use of theoretical modelling. It is seen here that the Swedish infrastructure manager (the Swedish Transport Administration) so far has no method for calculation of marginal costs as a base for charging, especially for costs of scarce capacity, and that the infrastructure manager is applying or discussing various methods for allocations of scarce track capacity. The EU-recast gives no guidance on principles for calculation of charges for scarce capacity, so we recommend the Swedish Transport Administration to develop such charges. The Administration seems to ignore important externalities that should be taken into consideration from a welfare point of view, with respect both to efficient charging and to allocation of scarce capacity. The analytical modelling part of the paper aims to derive these charges in principle, taking these externalities into account. If financing charges exceeding social marginal costs are applied, the model shows how to minimise the welfare loss of these increases. It also shows that financing charges should primarily be applied to market segments that cause large external costs from the operation of the train, where its customers have low valuation of wait time and delay time, where customers of other segments have high valuations of delay and where increased profits for other operators are induced.  相似文献   
5.
Function and object of existing control systems for traction and stability are described. The problem of rating and objective evaluation of the influence of such slip control systems on vehicle dynamics is demonstrated. Closed-loop manoeuvres with subjective assessment and open-loop tests with measured data are shown. Analysis of correlation results in characteristic values which allow assessment of dynamic performance of slip control systems. Tests on natural and synthetic μ-low road surface with two passenger cars, equipped with different slip control systems, demonstrate the objective test method and show their results.  相似文献   
6.
Optimal economic interventions in scheduled public transport   总被引:1,自引:0,他引:1  
This chapter analyses appropriate regulatory instruments for public transport markets under monopoly and competition, respectively. For the monopoly case, the operator chooses too low supply, compared to welfare optimum. In contrast, for the competition case the operators choose too high supply, at least for the competition model that we have considered most appropriate. It is found that under monopoly a subsidy should be applied, while under competition taxation should be applied.  相似文献   
7.
The strait between Novaya Zemlya and Frans Josef Land, here called the Barents Sea Exit (BSX) is investigated using data obtained from a current-meter array deployed in 1991–1992, and two numerical models (ROMS and NAME). Combining the observations and models the net volume flux towards the Arctic Ocean was estimated to 2.0 ± 0.6 Sv (1 Sv = 106 m3s? 1). The observations indicate that about half of this transport consists of dense, Cold Bottom Water, which may penetrate to great depths and contribute to the thermohaline circulation. Both models give quite similar net transport, seasonal variations and spatial current structures, and the discrepancies from the observations were related to the coarse representation of the bottom topography in the models. Also the models indicate that actual deployment did not capture the main in- and outflows through the BSX. A snapshot of the hydrographic structure (CTD section) indicates that both models are good at reproducing the salinity. Nevertheless, they react differently to atmospheric cooling, although the same meteorological forcing was applied. This may be due to the different parameterisation of sea ice and that tides were included in only one of the models (ROMS). Proxies for the heat transport are found to be small at the BSX, and it can not be ruled out that the Barents Sea is a heat sink rather than a heat source for the Arctic Ocean.  相似文献   
8.
ABSTRACT

Vehicle simulation has a long tradition in the automotive industry as a powerful supplement to physical vehicle testing. In the field of Electronic Stability Control (ESC) system, the simulation process has been well established to support the ESC development and application by suppliers and Original Equipment Manufacturers (OEMs). The latest regulation of the United Nations Economic Commission for Europe UN/ECE-R 13 allows also for simulation-based homologation. This extends the usage of simulation from ESC development to homologation. This paper gives an overview of simulation methods, as well as processes and tools used for the homologation of ESC in vehicle variants. The paper first describes the generic homologation process according to the European Regulation (UN/ECE-R 13H, UN/ECE-R 13/11) and U.S. Federal Motor Vehicle Safety Standard (FMVSS 126). Subsequently the ESC system is explained as well as the generic application and release process at the supplier and OEM side. Coming up with the simulation methods, the ESC development and application process needs to be adapted for the virtual vehicles. The simulation environment, consisting of vehicle model, ESC model and simulation platform, is explained in detail with some exemplary use-cases. In the final section, examples of simulation-based ESC homologation in vehicle variants are shown for passenger cars, light trucks, heavy trucks and trailers. This paper is targeted to give a state-of-the-art account of the simulation methods supporting the homologation of ESC systems in vehicle variants. However, the described approach and the lessons learned can be used as reference in future for an extended usage of simulation-supported releases of the ESC system up to the development and release of driver assistance systems.

Abbreviations: ABS: Anti-lock braking system; ADR: Australian design rules; ALB: Automatic load-dependent brake force controller; AMEVSC: Alternative method to assess the electronic vehicle stability control system; APP: Application; BSC: Brake slip controller; CAE: Computer-aided engineering; CAN: Controller area network; CAT: Category; CoG: Centre of gravity; DIN: Deutsches Institut für Normung (German Institute for Standards); EB+: Trademark of Haldex; EBD: Electronic brake force distribution; EBS: Electronic brake system; ECU: Electronic control unit; ESC: Electronic stability control; ECVWTA: European Community Whole Vehicle Type Approval; FMVSS: Federal motor vehicle safety standards; GPS: Global positioning system; GRRF: Groupe de travail en matiere de roulement et de freinage (Working Party on Braking and Running Gear); HiL: Hardware-in-the-Loop; HSRI: Highway Safety Research Institute; K&C: Kinematic and compliant (KnC); MBS: Multibody systems; MPV: Multipurpose vehicle; NHTSA: National Highway Traffic Safety Administration; OEM: Original equipment manufacturer; SiL: Software-in-the-Loop; ST: Summer tyres; STM: Single track model; StVO: Straßenverkehrsordnung (Government Highway Regulations); SUV: Sports utility vehicle; SW: Software; SwD: Sine with dwell manoeuvre; TC: Threshold consumption value; TCS: Traction control system; TRIAS: Test Requirements and Instructions for Automobile Standards; UN/ECE: United Nations Economic Commission for Europe; VAF: Value-added function; VDC: Vehicle dynamics controller; VTC: Vehicle test catalogue; WT: Winter tyres  相似文献   
9.
The image of the shipping industry plays a vital role in developing maritime transport as a major future, sustainable transport alternative. In particular, it is crucial to understand the image the shipping industry has among young people and the anatomy of the concept in order to be able to effectively promote careers in shipping, to cultivate shipping as an attractive labour market and to develop attractive educational programmes. The focus of this paper is the image of the shipping industry. This study reports on the findings of a large-scale survey of the image of shipping- and image-related concepts among upper secondary school pupils in Sweden, Norway and Greece. We define and analyse empirically by means of multivariate statistical analysis the anatomy of the image concept. We identify various image dimensions, estimate how young people rate the shipping industry along these dimensions and estimate their relative importance to young people who are planning their future careers. The results from this study can be used as a base for describing and explaining the images that young people have of the shipping industry. Such knowledge is fundamental for deriving and developing constructive strategies to promote careers in shipping, to adapt shipping to the expectations of young people and to develop creative and relevant educational programmes. Finally, understanding the image of shipping among young people is important not only for the shipping industry, but for other stakeholders as well, such as ship-owners associations, trade associations, labour unions, transport authorities and administrations and policy makers at the national and supra-national level.  相似文献   
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