政府介入有利于市场增长

<正>无论是从企业本身业务还是市场宏观角度来看,不得不说多数企业其实都希望能得到政府介入的帮助。这或许是人类的自然天性。特别是处于抓住新发展机遇的关键时刻,政府介入无疑是一剂强力的催化剂。上世纪60年代,政府介入汽车工业,推行碰撞安全相关的法律法规。当时,安全带在西欧、日本和美国被强制推行,也由此造就了     

Schlieren,Shadowgraph, Mie-scattering visualization of diesel and gasoline sprays in high pressure/high temperature chamber under GDCI engine low load condition

Three visualization methods, Schlieren, Shadowgraph, and Mie-scattering, were applied to compare diesel and gasoline spray structures in a constant volume chamber. Fuels were injected into a high pressure/high temperature chamber under the same in-cylinder pressure and temperature conditions of low load in a GDCI (gasoline direct injection compression ignition) engine. Two injection pressures (40 MPa and 80 MPa), two ambient pressures (4.2 MPa and 1.7 MPa), and two ambient temperatures (908 K and 677 K) were use. The images from the different methods were overlapped to show liquid and vapor phases more clearly. Vapor developments of the two fuels were similar; however, different liquid developments were seen. At the same injection pressure and ambient temperature, gasoline liquid propagated more quickly and disappeared more rapidly than diesel liquid phase. At the low ambient temperature and pressure condition, gasoline and diesel sprays with higher injection pressures showed longer liquid lengths due to higher spray momentum. At the higher ambient temperature condition, the gasoline liquid length was shorter for the higher injection pressure. Higher volatility of gasoline is the main reason for this shorter liquid length under higher injection pressure and higher ambient temperature conditions. For a design of GDCI engine, it is necessary to understand the higher volatility of gasoline.     

A dynamic CSTT model for the effects of added nutrients in Loch Creran, a shallow fjord

Despite a tendency for the complexity of physical–biological models to increase, simple coupled models remain useful for some applications and can provide insights into crucial links between physical and biological processes. This argument is illustrated with an account of a simple 3-box model intended to help assess the capacity of fjords to assimilate nutrients from fish farms. The model, a dynamic version of the UK “Comprehensive Studies Task Team” (CSTT) steady-state model for eutrophication, was applied to Loch Creran (Scottish Western Highlands) and was implemented using Stella 8 and tested using historical data from 1975 (before the installation of a salmon farm) and field data collected in 2003, during the period of operation of the farm. The model's biological state variables are chlorophyll, dissolved inorganic nitrogen (DIN) and dissolved inorganic phosphorus (DIP), and it includes a simple run-off model to convert rainfall into river discharge. The physical processes involved in exchange between the loch and the adjacent waters of the Firth of Lorne were parameterised as a constant daily exchange rate.Between 1975 and 2003, local inputs of nutrient increased but, despite this, there was little apparent increase in nutrient concentrations in the loch, and observed chlorophyll concentrations decreased substantially. Model simulations of chlorophyll and DIN agreed well with observations in 1975, as did DIN simulations in 2003. However, simulated chlorophyll was overestimated in 2003.Some of the agreement between observations and simulations come from the use of observed boundary conditions to force the model. However, even when boundary conditions are subtracted from simulations and observations, the simulations in most cases retain a significant correlation with observations, demonstrating that the model's ‘interior’ processes do add to its ability to replicate conditions in the loch.     

物流学的应用

Paul French上海报道，随国内日趋壮大的消费队伍电器购买需求的增长，激烈的价格战已经侵蚀了大量利润，而更加完善的物流和分销手段也许正是解决这一问题的关键所在。[编按]     

The challenge of liberalising domestic airline competition in a less developed country

A new wave of liberalisation of domestic airline competition is taking place in less developed nations, although the initial motivation in most cases is to supplement the capacity of the government's own airline. Liberalisation tends to begin with free market entry and a strong interest in privatisation while other regulatory controls are maintained. This position is untenable and policy makers in the less developed countries are having to learn quickly without the benefit of the detailed analyses that preceded liberalisation in the developed countries. This paper explores these problems and focuses on the lessons that policy makers in the less developed countries can draw from experiences elsewhere.     

Labour relations and the transfer of the Panama Canal[1]

The international maritime community is concerned about Panama's preparedness to undertake the responsibility of what many consider to be the world's greatest maritime asset, the Panama Canal. In accordance with treaty provisions, the longer within the dominion of the U.S. government and its attendant regulatory framework and policies. To a great extent, Panama's efforts to prepare for the transfer thus far have been driven by its objective of a seamless transfer, whereby the status quo (meaning the Canal's existing institutional and organizational framework and attendant policies and procedures) would be preserved as much as possible. This would assure the maritime community that it can expect the same service and cost standards traditionally enjoyed under the Panama Canal Commission's stewardship. Still of great concern, however, is the continued reliability and productivity of the Canal's labour force; the Canal's reliability and efficient performance in the past is often attributed to its history of harmonious labour management relations. This article addresses some of the critical labour relations issues that will need to be considered even if Panama's status quo objective for the transfer is achieved.     

Policy challenges of increasing automation in driving

The convergence of information and communication technologies (ICT) with automotive technologies has already resulted in automation features in road vehicles and this trend is expected to continue in the future owing to consumer demand, dropping costs of components, and improved reliability. While the automation features that have taken place so far are mainly in the form of information and driver warning technologies (classified as level I pre-2010), future developments in the medium term (level II 2010–2025) are expected to exhibit connected cognitive vehicle features and encompass increasing degree of automation in the form of advanced driver assistance systems. Although autonomous vehicles have been developed for research purposes and are being tested in controlled driving missions, the autonomous driving case is only a long term (level III 2025 +) scenario. This paper contributes knowledge on technological forecasts regarding automation, policy challenges for each level of technology development and application context, and the essential instrument of cost-effectiveness for policy analysis which enables policy decisions on the automation systems to be assessed in a consistent and balanced manner. The cost of a system per vehicle is viewed against its effectiveness in meeting policy objectives of improving safety, efficiency, mobility, convenience and reducing environmental effects. Example applications are provided that illustrate the contribution of the methodology in providing information for supporting policy decisions. Given the uncertainties in system costs as well as effectiveness, the tool for assessing policies for future generation features probabilistic and utility-theoretic analysis capability. The policy issues defined and the assessment framework enable the resolution of policy challenges while allowing worthy innovative automation in driving to enhance future road transportation.     

Strategic intent: Guiding port authorities to their new world?

Following the financial tsunami many organisations are facing greater risks to their sustainability. Strategic collaborations in logistics networks, of which ports are a significant node, reduce risks for all organisations in the network, increase an organisation's ability to access efficiencies such as economies of scale and create opportunities for learning. The knowledge learnt from collaborators is enhanced by managing the key relationships and forming a strategic intent to learn for mutual benefit. Mutual benefits may include market information or innovation. As Awad and Ghaziri (2004, p. 17) comment ‘Beyond efficiency and productivity, the real benefit of collaboration is innovation.’ The more central the port authority is in this network, the greater are the opportunities for learning. Three key factors are critical for port authorities to integrate knowledge from networks; firstly, there are levels of common knowledge that enable effective communication, including concepts, behavioural norms, language and experience. Secondly integrative efficiency requires organisational routines which foster knowledge sharing through frequent, coordinated activities that are repetitive. Thirdly efficient structures within the port authority help maintain effective and efficient communication to minimise the knowledge loss on integration. Strategising provides opportunities for port authorities to steer the critical path between maintaining their current sources of competitive advantage and developing future resilience through innovation opportunities provided by learning from their trading networks. Port authorities, by developing skills in reading the collective mind and interpreting information available in trading networks, can foster resilience into the future. Given the current risky prognosis for the short-medium term following the financial tsunami, instigating strategies that may lessen those risks may be an option for port authorities.     

Investigating effects of asphalt pavement conditions on traffic accidents in Tennessee based on the pavement management system (PMS)

Pavement maintenance is essential for ensuring good riding quality and avoiding traffic congestion, air pollution, and accidents. Improving road safety is one of the most important objectives for pavement management systems. This study utilized the Tennessee Pavement Management System (PMS) and Accident History Database (AHD) to investigate the relationship between accident frequency and pavement distress variables. Focusing on four urban interstates with asphalt pavements, divided median types, and 55 mph speed limits, 21 Negative Binomial Regression models were developed for predicting various types of traffic accident frequencies based on different pavement condition variables, including rut depth (RD), International Roughness Index (IRI), and Present Serviceability Index (PSI). The modeling results indicated that the RD models did not perform well, except for predicting accidents at night and accidents under rain weather conditions; whereas, IRI and PSI were always significant prediction variables in all types of accident models. Comparing the models goodness‐of‐fit results, it was found that the PSI models had a better performance in crash frequency prediction than the RD models and IRI models. This study suggests that the PSI accident prediction models should be considered as a comprehensive approach to integrate the highway safety factors into the pavement management system. Copyright © 2010 John Wiley & Sons, Ltd.