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141.
对国内某油田注水管线的结垢现象及水质和垢物成分进行了分析,探讨了强磁防垢机理,研究了磁处理的特点。通过室内晶相显微观察法。优化选择强磁处理的最佳磁参数,根据最佳磁参数设计出适合此油田现场使用的强磁防垢器,并在油田现场安装磁化器实施强磁防垢技术.观察磁防垢前后注水管线状况和结垢对比。现场实践表明,强磁防垢技术不但操作方便,而且可取得显著的效果和经济效益。 相似文献
142.
This special issue integrates eleven papers focussing on indicators able to convey the multiple expectations that society has concerning agricultural land. As scale issues have been so far overlooked within this research topic, a particular focus of this themed issue is to highlight the need for reconciling assessments across scales. The shared purpose of the contributions is to examine how the multiple societal expectations concerning agrarian landscapes might be incorporated into land use policy at different governance levels.A core set of these papers were presented in the symposium “Linking social indicators across scales”, to the European Congress of the International Association of Landscape Ecology (IALE) in September 2013 in Manchester, UK. This symposium was organized to create the time and space for a discussion on the issues of scale when capturing societal preferences concerning agrarian landscapes. While the landscape scale was specifically addressed by four papers, seven papers examined broader geographic units in addition to up-scaling and downscaling issues. 相似文献
143.
Land exploitation, as an important strategy to mitigate farmland loss and stabilize grain production, has been adopted to compensate farmland loss due to rapid urbanization in China. Bounded by the limited capacity and obvious spatial variations of national farmland reserves, it is essential to arrange land exploitation activities timely and reasonably. In this study, we propose an indicator for the status of regional land exploitation, the Exploitation Degree, to facilitate an overview of land exploitation programs in China at both provincial and prefectural levels based on project data from 2006 to 2012. To further our understanding of the regional features of land exploitation activities, we employ the Lasso model to identify and quantitatively assess influencing factors on land exploitation. Our study shows that: (1) contemporary land exploitation practices in China are significantly inconsistent across exploitable farmland reserves. Some areas are greatly over-exploited and such irrational land exploitation has been persistent; (2) related national land plans designed to guide land exploitation efforts centered on resource-rich regions and critical areas do not function as intended. Therefore, we suggest that Chinas land exploitation policy shall be improved by reconsidering the orientation of land exploitation policy, coordinating land exploitation activities with productivity improvements and eco-system protection, and enhancing the power and scope of the plans in controlling and guiding land resource management. 相似文献
144.
In a first for South Africa, this article draws on literature on infrastructure productivity to model dynamic economy-wide employment impacts of infrastructure investment funded with different fiscal tools. Using a dynamic computable general equilibrium model, the South African investment plan is modelled, given the infrastructure externality. Alternative fiscal scenarios to finance the policy are modelled in the article. In the long run, unemployment decreases for all types of workers under one of the scenarios. In the short run, only elementary occupation workers benefit from a decrease in unemployment; for the rest, unemployment rises. 相似文献
145.
This paper focuses on the estimation of direct damages caused by three flood scenarios with different return periods in the section Făgetul de Sus – Ghimeş – Palanca Pass of Trotuș River, with the aim of highlighting the need of improved land use plans. The damage for three land use classes (residential building, infrastructure and agriculture) were estimated using the damage curves developed by the European Joint Research Centre (JRC) as well as site specific maximum damage values. The data were processed with the help of the ArcMap 10.2 software and FloodRisk tool from QGIS software. Furthermore, the flood risk was assessed using the damage – probability curves, which associates the damage with the corresponding frequency of occurrence. This method was identified and adapted to the characteristics of the study area in order to develop a methodology of flood risk assessment that is answering the question: does the lack of land use plans increase the vulnerability and the flood damage? The results showed that the greatest damages are registered for the residential building land use class for a flood probability of 0.001. In this case the damages reach up to 60% on the scale range of deterioration factor, the total damage value being 2 million euros. For the same hazard probability the total registered damage value for roads is 7500 euro, for railways is around 12,000 euro, while for agriculture is around 84,000 euro. These results highlight the need of protection measures and land use plans development and implementation. Regarding the protection measures we consider that the egalitarianism would be the concept that should be applied in the study area and also an improved cooperation between government, specialized agencies and local authorities at local level would lead to a more efficient flood risk management process. The proposed methodology can be applied for micro-scale analysis, providing quantitative results regarding the flood damage and flood risk assessment. It includes a detailed vulnerability analysis of the elements-at-risk with the aim of developing a more comprehensive approach of flood risk assessment. 相似文献
146.
宋歌 《无锡商业职业技术学院学报》2014,14(5):110-112
在非时政类报刊陆续走向市场的大环境下,行业报刊的市场化势在必行。行业报刊的市场化经营,必须建立一支既懂行业报刊新闻业务,更懂行业报刊经营管理的人才队伍;必须建立与行业报刊市场化相适应的运作机制;必须注重实施行业报刊产业链发展战略。 相似文献
147.
A yard template determines the assignment of spaces in a yard for arriving vessels. Fluctuation of demand for freight transportation brings new challenges for making a robust yard template when facing uncertain maritime market. A model is proposed for yard template planning considering random numbers of containers that will be loaded onto vessels that visit the port periodically. Traffic congestions and multiple schedule cycle times for vessel arrival patterns are also considered. Moreover, a meta-heuristic method is developed for solving the model in large-scale cases. Numerical experiments are conducted to validate effectiveness and efficiency of the model. 相似文献
148.
A right of commoners to pastures existed since the Early Middle Ages in Anglo-Saxon England and the European mainland, including Tyrol in Austria. Lowland commons institutions were largely dissolved by the 19th century; however, in the European Alps contiguous commons remain alive. Some two thousand alpine commons institutions are registered in the Tyrolean parcel cadaster and land registry. A specific study of West-Tyrolean commons (known as Agrargemeinschaft or AGMs), framed by Ostrom's design principles is presented. General lessons for land policy and land administration are extracted. An interview period was split between the Inn valley and the Ötztal. Roughly half are considered independent: others are regulated by the Tyrolean Agricultural Authority. Some AGMs hold the full bundle of land rights: others only hold pastoral and forestry rights. AGMs consisted either of a single cadastral parcel or several contiguous parcels. In the Inn valley villages the pastoral commons were owned by the municipalities, while in the researched Ötztal, AGMs are frequently the full owners of the commons. AGM membership ranges between 5 and 60 farm households. The number of livestock units pastured was in most cases stipulated in approved regulations. Alpine commons larger than 200 ha are also hunting-zones: revenue is collected from the lease of hunting rights. Most of the alpine commons are designated and used as ski-zones. Upper portions of two alpine commons in the Ötztal are state protected natural areas. The number of farms with pastoral rights is declining at District and State level. Key lessons for land policy and land administration include: Ostrom's design principles being a precondition rather than a panacea; commons institutions requiring one clear ownership party; both public and collective ownership producing success; publically owned commons requiring a local representative; small membership numbers being preferable; small shareholdings not being preferable; decentralized governance being beneficial; internal democratic elections being beneficial; internal boundary records being superfluous; explicit sanctions being superfluous; mixed economies being acceptable; and geography being a significant influence on the longevity of pastoral commons. 相似文献
149.
The conception of impression management has been widely used for investigating issues such as presentation of staff and enterprise images, or the interaction between customers and service workers. The existing studies in tourism and hospitality tended to adopt an early framework of impression management, thus neglecting the recent development of impression management studies. To enhance the understanding of impression management in relation to tourist service, the present study was conducted to disclose the various strategies tour leaders use for image building or self-presentation. The data were drawn from in-depth interviews. The results showed that diverse tactics, verbal and nonverbal, were employed for impression management in tour operation. Another finding of this study was that the impression management strategies are not mutually exclusive; instead, various links exist among the strategies. The implications for future studies and industry practice were discussed. 相似文献
150.
The growing demand for a wide range of private and public goods and services from a finite land resource is increasingly challenging for planners at local, regional, national and international scales. The Scottish Government's development of a Land Use Strategy has given salience to resolving conflicts and enhancing synergies in land use. In Scotland, the poorest quality farmland is often designated for nature and landscape conservation and the highest quality farmland often protected for food production. This means that many of the competitive pressures on land are experienced in what we term the ‘squeezed middle’. The paper identifies the multiple (and not exclusively economic) drivers of land use choices and, through an ecosystem services lens, explores three particular areas of land use conflict. These are (i) the continued high level of public support for farming, which has done little to address the problem of low farm incomes; (ii) the pressure to increase woodland planting on farm (and other) land; and (iii) conflicts associated with intensive game management, especially on sporting estates. Using the Scottish situation as an example, the heterogeneity of land use pressures means that there is a danger of the principles of the Land Use Strategy becoming lost in translation from national policy to practical land use decision-making. The appropriate scale for delivery of integrated ecosystem services may therefore be more local than current pilot projects, and may require more active participation of land managers. It may also require policy instruments that are more flexible in adapting to the local context, including payments for ecosystem services. 相似文献