半导体存储器及发展趋势

半导体存储器的容量和速度决策着计算机系统运行速度。目前CPU芯片18个月一更新，为了赶上这个速度，半导体存储器的发展也日新月异。     

传统能源及碳交易价格与新能源股价——基于VAR和CAPM-GARCH模型的分析

文章构建VAR模型和CAPM-GARCH模型,分析检验了2010年7月初至2013年底期间传统能源和碳排放权交易价格对国内新能源上市公司股价波动的影响及新能源股票收益率的波动特点,研究发现:国内煤价对新能源公司股价有显著的正向影响,而国际油价的影响不显著;碳排放权交易价格也是引起新能源投资价值从而上市公司股价变动的重要因素;新能源公司股价指数对高科技股价指数并不敏感,反映出国内新能源上市公司科技含量不足,资本市场关注更多的是新能源的概念而非技术优势;国内新能源股票整体的系统风险在1.125~1.131之间,利好消息比利空消息能引起新能源股票收益率更大的波动。     

Exploring under-utilised low carbon land resources from multiple perspectives: Case studies on regencies in Kalimantan

Mobilising under-utilised low carbon (ULC) land resources for future agricultural production can help reducing pressure on high carbon stock land from agricultural expansion, particularly for deforestation hotspots like Kalimantan. However, the potential of ULC land is not yet well understood, especially at regency level which is the key authority for land-use planning in Indonesia. Therefore, this study explored ULC land resources for all regencies in Kalimantan. By analysing information from six monitoring domains, a range of indicators were derived to provide insights into the physical area of ULC land from various perspectives. It was found that these indicators show largely different values at regency level. For example, regency Pulang Pisau has a substantial area of ‘temporarily unused agricultural land’ but a very limited area of ‘low carbon land’ – this implies that not all ‘temporarily unused agricultural land’ is ready for future exploitation when assessing from different aspects. As a result of such diverging indicators, using a single indicator to quantify available ULC land resources is risky as it can either be an over- or under-estimation. Thus, ULC land resources were further explored in the present paper by taking four regencies as case studies and comparing all the indicators, supported with relevant literature and evidence collected from narrative interviews. This information was used to estimate ULC land area by possible land-use strategies. For example, Gunung Mas was found to have a large area of low carbon land which is not occupied and might be suitable for oil palm deployment. However, the major limitation is that physical estimates cannot provide a complete picture of ‘real’ land availability without considering a broader range of socio-economic factors (e.g. labour availability). Therefore, physical land area indicators from different domains must be combined with other qualitative and quantitative information especially the socio-economic factors underlying land under-utilisation to obtain better estimates.     

Is the protection of beach and dune vegetation compatible with tourism?

The paradox of development vs. protection and conservation of the coasts highlights the need to determine if tourism and conservation can be compatible rather than opposite activities. We analyzed the spatial and temporal changes in vegetation cover, composition and diversity in three beaches located in the state of Veracruz (Mexico) with different levels of tourism activity (Natural, Trailer Park and Hotels). We calculated tourist density and evaluated vegetation cover, species richness and diversity and analyzed the changes before and after three holiday seasons (winter, spring and summer). The Natural site had the highest vegetation cover (42.8 m²), species richness (14) and diversity (1.50), and Trailer Park the lowest (4.9 m², 8 species, and 0.897 respectively). The BACI (Before-After-Control-Design) analysis showed no significant differences before and after the holiday seasons. Our results show how low and medium density tourism can be compatible with the protection of beach and coastal dune vegetation.     

Socio-technical transition governance and public opinion: The case of passenger transport in Finland

As a governance perspective, transition management views the engagement of a wide variety of stakeholders in policy development as a necessary element in furthering sustainability through enhanced social learning. Yet as a literature it has paid relatively little attention to public consultation on socio-technical change. Here we set transition management in the context of longstanding debates in science and technology studies, technology assessment and deliberative democracy. Empirically, we use national survey data on Finnish public opinion of state support for future transport options. Showing how transport practices and attitudes to transport innovation policy vary with both demography and geography, we argue that these differences have implications for policy legitimacy. We suggest that, both given and despite the practical difficulties of deliberative democracy, use of participative opinion surveying to better understand social groups with needs and interests that differ from national averages, may help to enhance policy legitimacy and hence the success of transition management.     

Clustered airline flight scheduling: Evidence from airline deregulation in Korea

This paper explores the impacts of competition level on airline scheduling in the Korean domestic short-haul routes where a hub-and-spoke system is not the optimal air transport network strategy. The empirical findings using the Korean airline panel data for the period 2006–2010 suggest that competition leads to less differentiated departure flight times as expected from spatial competition theory. Unlike the previous study on the U.S airline industry, the degree of this tendency for less differentiation differs across the type of routes: the Jeju island routes (leisure type) and the inland routes (business type), in the deregulated period. Following the May 2008 Deregulation Act we find an increasingly clustered pattern of airline scheduling in the Jeju island routes where there have been competitive pressures associated with new low cost entrants. This recent evidence would imply that airline carriers strategically schedule departure flight times and allocate flights between routes as competition increases in the deregulated period.     

双线曲线铁路桥测量控制方法与分析

双线曲线桥的坐标计算及测量控制,是简支梁桥测量工作中的难点及重点部分,做好墩位及各部几何尺寸的控制是该桥的重难点工作。本文针对其测量控制方法进行分析。     

转变城市发展方式之低碳城市建设——基于德国经验借鉴

首先从产业能源体系、低碳交通网络及生态环境三方面梳理德国低碳城市建设实践,然后总结德国在低碳意识培养、战略目标制定、政策体系建设等方面值得借鉴的经验,最后从“公平-效率-质量”视角为我国低碳城市建设提出建设路径:加快创新驱动,提高建设效率;提供制度支持,注重建设公平;强调以人为本,提升建设质量。     

Potential economic impacts of zero thresholds for unapproved GMOs: The EU case

As the pipeline of new biotech crops has continued to expand, regulatory approvals of such crops across different countries have become less synchronized. As a result, some biotech crops can be cultivated in one or more countries but may not be approved for use in others. Under such circumstances, small amounts of unapproved biotech crops can be found in the food/feed supplies of some countries and under zero threshold policies they must be withdrawn and can lead to market disruptions. In this paper we examine the potential economic implications of regulatory asynchronicity and zero threshold policies for unapproved GMOs using the EU as a case study. To measure the potential economic impacts from possible trade disruptions between the EU and its major suppliers of soybeans, we develop a spatial equilibrium model and examine alternative scenarios where bilateral trade flows are set to zero. From our analysis we find that when asynchronous approvals become a systemic problem leading to trade disruptions with multiple trading partners the impacts can be severe. For instance, we find that if the EU were to stop imports from its three main suppliers the US, Brazil and Argentina, it would pay roughly 220% more for soybeans, 211% more for soybean meal and 202% more for soy oil.     

A study on the importance of airline selection attributes by airline type: An emphasis on the difference of opinion in between Korean and overseas aviation experts

The main purpose of this research is to understand the relative importance of airline selection attributes that are considered important by passengers when selecting an airline. Specifically, we analyzed how the attribute selections differed based on airline types, a Full Service Carrier (FSC) and a Low Cost Carrier (LCC). For this purpose, a Delphi analysis was performed with 34 Korean aviation experts and 32 overseas aviation experts as the target sample groups. Statistical tests including Mann-Whitney U Test and Wilcoxon Signed Rank Test, were used to analyze the selection attributes. In the case of FSCs, safety, flight schedule, cabin interior, and fast check-in processes were considered to be important selection attributes whereas for LCCs, air fare level, flight safety, the convenience of air ticket purchasing procedures, and additional charges were considered to be the important selection attributes. Additionally, there was a difference in the importance of airline selection attributes depending on whether it was a Korean or overseas aviation market. The result of these findings may be utilized as basic data in establishing a marketing strategy for an airline company to attract more passengers.