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91.
Land use change is strongly modifying the traditional landscape of hilly productive Mediterranean sites. An example of these circumstances is the Langhe region (Piemonte, NW Italy), where woody plantations such as vineyards and orchards have been cultivated on hillslopes for centuries. In this paper we assess landscape changes occurred in the Diano study area (2651 ha) in the 1954–2000 period and we ascertain land use transition paths and rates of this rural ecosystem. Land use mapping obtained from object-oriented analysis of aerial photographs was used to quantify land use changes between 1954 and 2000. To examine the spatio-temporal patterns of land use change over time, a set of spatial statistics capturing different dimensions of landscape change was identified. An increase of landscape heterogeneity from 1954 to the present was observed due to the expansion of orchards and the fragmentation of field crops. A significant portion (55%) of current orchards surface is represented by former field crops, 24% by vineyards and 15% by forests. The strong expansion of hazelnut orchards concurred to the fragmentation of traditional rural landscape was dominated by vineyards, field crops and forests. Hazelnut orchards expansion was mainly located in places where grapes cultivation was less remunerative. A further expansion of hazelnut in the area should be planned, discussed and carefully monitored through change detection studies in order to avoid potential unsustainable use of the land. 相似文献
92.
Delineating travel patterns and city structure has long been a core research topic in transport geography. Different from the physical structure, the city structure beneath the complex travel-flow system shows the inherent connection patterns within the city. On the basis of taxi-trip data from Shanghai, we built spatially embedded networks to model intra-city spatial interactions and to introduce network science methods into the analysis. The community detection method is applied to reveal sub-regional structures, and several network measures are used to examine the properties of sub-regions. Considering the differences between long- and short-distance trips, we reveal a two-level hierarchical polycentric city structure in Shanghai. Further explorations of sub-network structures demonstrate that urban sub-regions have broader internal spatial interactions, while suburban centers are more influential on local traffic. By incorporating the land use of centers from a travel-pattern perspective, we investigate sub-region formation and the interaction patterns of center–local places. This study provides insights into using emerging data sources to reveal travel patterns and city structures, which could potentially aid in developing and applying urban transportation policies. The sub-regional structures revealed in this study are more easily interpreted for transportation-related issues than for other structures, such as administrative divisions. 相似文献
93.
Hwasung Song 《Asia Pacific Journal of Tourism Research》2018,23(2):133-145
This study examined the travel motivation of international students in Korea using the theory of travel career pattern (TCP). In particular, latent profile analysis (LPA) was applied to identify latent classes within international students. Based on the results, four latent profiles were derived and named “Core,” “Longing,” “Middle,” and “Veteran.” The results described the travel motivation and patterns across these four profiles to enhance the understanding of international students in the context of tourism. There were significant differences in travel patterns (i.e. travel companion and information sources) among the profiles segmented by motivation. This study has expanded travel motivation research by (a) applying TCP to an understudied population (i.e. international students in a non-English-speaking country); (b) comparing travel careers between the home country, Korea (i.e. a study abroad destination), and the third countries; and (c) highlighting LPA as a clustering tool to understand travel motivation. 相似文献
94.
AbstractThe present study investigates how the most foundational factors to individual differences – personality traits and personal values – affect the perceived safety of genetic modification and their relative importance. Publicly available communication data from 522 Twitter accounts discussing genetically modified foods and their safety was processed in two steps. First, accounts were categorized by the researchers as viewing GM foods as either safe or not safe. Second, using the IBM Watson platform, the Twitter communication data were subjected to lexical analysis to assign scores according to the Five Factor Model for personality traits and Schwartz’s basic individual values to the individual accounts. Logistic regression analyses were performed to determine how perceived GM food safety is linked to personality traits and individual values. Although both traits and values significantly contribute to explaining GM attitudes, personality traits strongly moderate the effect of individual values on risk perception. 相似文献
95.
96.
基础会计学科是一门专业性和应用性较强的学科,因此学好它有着非常重要的作用。本文主要就是从基础会计课程的各章节入手,从原有的框架入手,然后对理论教学与实际工作中不同的经济业务运营手段进行研究,使学生易于把握其内在的规律,在学习和复习过程中能够抓住重点,做到提纲挈领,学习起来得心应手。 相似文献
97.
基于CGSS数据,利用Heckman样本选择模型对中国国有部门与非国有部门的工资差异和影响因素进行系统研究。回归结果显示,国有部门员工的教育收益率高于非国有部门,教育收益率与学历水平呈现正相关关系,与非国有部门相比,国有部门中大学本科及以上学历员工的教育收益率更高。工资差异分解结果表明,两部门全样本工资差异中市场歧视占比高于特征差异占比,与全样本相比,大学本科及以上学历员工的工资总差异和特征差异占比更高,系数差异占比更低,说明高学历群体中部门间工资差异更为明显,而且两部门中仍存在较严重的劳动力市场分割和就业歧视问题。因此,政府应努力消除劳动力的流动性障碍,深化国有部门市场化改革,制定更为合理的工资机制,以促进中国经济的持续健康稳定增长。 相似文献
98.
文章从正确认识我国现阶段基本国情和阶段性特征,准确把握社会主义初级阶段乃至整个中国特色社会主义基本路线,深刻领会科学发展观和十七届五中全会精神三个方面,论证了以经济建设为中心是中国特色社会主义的永恒主题。 相似文献
99.
100.
目的:探讨基础医学课程在护理专业的中存在的相关问题;方法:对其开设的合适与否以及后期临床课程的学习及临床工作的直接关系进行分析;结果:现阶段我校护理专业基础医学课程存在学时的分配、教材的选择、教师的教育背景及教学方法等不尽人意之处;结论:护理专业医学基础课程设置与安排有待进一步改进。 相似文献