Why I am a Psychology Major: An Empirical Analysis of Student Motivations

The underlying “architecture of the decision to pursue a degree in psychology was quantified using the Method of Sorting technique to identifying the critical issues necessary to make this choice. Multidimentsional scaling procedures were employed to construct a three-dimensional map representing the relationships between reasons for selecting psychology as a major. Freshman and senior psychology majors (N = 165) from a regional university and a large research-based institution rated the relative importance of items in their decision-making process. Hierarchical clustering procedures revealed seven different groups of students. Although significant differences associated with class standing were not found, institutional affiliation did influence cluster composition. Reflecting local emphases, students at the regional institution had a greater interest in Counseling Psychology, whereas those at the research-based school focused on Clinical Psychology. This semantic map and the associated item clusters arising from psychology student data provides an empirical basis for, amongst other things, course selection, faculty-initiated program design or revision, strategic niche marketing, and student retention.     

磁防垢除垢技术研究与应用新进展

回顾了磁防垢除垢技术的发展历程，介绍了磁防垢除垢技术的作用效果和应用情况，分析了磁防垢除垢技术研究现状和存在的问题，跟踪报道了磁防垢除垢技术研究的新进展。     

Addressing the social landscape dimensions: The need for reconciling cross scale assessments for capturing Cultural Ecosystem Services (CES)

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.     

Rural Residential Land Transition in the Beijing-Tianjin-Hebei Region: Spatial-Temporal Patterns and Policy Implications

Rural residential land transition (RRLT) dominates rural land use transition. Therefore, analysing the laws of transition and differentiation of land use is not only the basis for the differential management of rural residential areas but key to the sustainable use of rural land. This study constructs a conceptual model of RRLT using multi-period remote sensing monitoring data based on a comprehensive index method, ArcGIS, and FRAGSTATS landscape pattern analysis, among others. It also analyses the characteristics of the transition extent, transition trend, transition morphology, and transition intensity of rural residential land in the Beijing-Tianjin-Hebei (BTH) region from 1980 to 2018. The results show that, from a vertical comparison of long time series, the transition extent is characterised by a process of ‘slow growth—expanding start—fast expansion—slowing down’; the transition trend is characterised by an increase in the amount of cultivated land occupied by rural residential land, followed by a large number of rural residential land is reclaimed as cultivated land; the transition morphology is characterised by an increase in mean patch size and degree of irregularity, as well as aggregation; and the transition intensity is characterised by fluctuations in the process of ‘small-scale reduction—small-scale growth—substantial growth—small-scale growth and reduction’. A horizontal comparison of counties in the BTH region reveals a long-lasting and active growth trend in transition extent and transition intensity in the Beijing-Tianjin region, and a gradually slowing trend in the areas around the region. The transition morphology features of the northwest Hebei region are more prominent, and show that the scale of rural settlements is small, the plaques fragmented and irregular, and the layout more scattered. The BTH region should formulate a differentiated transition direction for rural residential areas based on the different functional areas, and play into the agglomeration, scale, and synergy effects of urban agglomerations. It should also coordinate and improve the human–land relationship in rural areas, and construct an orderly and densely distributed pattern of urban and rural spatial development with a reasonable layout and complementary functions.     

基于多维频谱地图的干扰规避

针对复杂电磁环境下卫星移动通信系统可靠通信需求，利用频谱地图多维数据呈现优势，提出了基于多维频谱地图的干扰规避方法。通过建立卫星移动通信系统波束、时隙、子频带、干扰强度等多维信息关联的频谱地图，利用数据挖掘方法对频谱可用情况进行预测，基于预测结果及用户QoS(Quality of Service)需求生成干扰规避策略，通过星地联合频谱资源调配实现系统干扰规避。该方法为卫星移动通信系统干扰规避提供了一种全新的思路，可提升卫星移动通信系统干扰防护能力。     

Reserves and cash flows under stochastic retirement

Uncertain time of retirement and uncertain structure of retirement benefits are risk factors for life insurance companies. Nevertheless, classical life insurance models assume these are deterministic. In this paper, we include the risk from stochastic time of retirement and stochastic benefit structure in a classical finite-state Markov model for a life insurance contract. We include discontinuities in the distribution of the retirement time. First, we derive formulas for appropriate scaling of the benefits according to the time of retirement and discuss the link between the scaling and the guarantees provided. Stochastic retirement creates a need to rethink the construction of disability products for high ages and ways to handle this are discussed. We show how to calculate market reserves and how to use modified transition probabilities to calculate expected cash flows without significantly more complexity than in the traditional model. At last, we demonstrate the impact of stochastic retirement on market reserves and expected cash flow in numerical examples.     

Influence of perceived risk on entrepreneurial desirability and feasibility: multidimensional approach for nascent entrepreneurs

This study examines the influence of perceived risk on entrepreneurial desirability and feasibility as determining factors in the intention to start a self-owned business. Specifically, a multidimensional approach is taken to examine the different types of risks associated with entrepreneurship: economic, social, time, health and personal risks. The results obtained from a sample of 376 new entrepreneurs in Mexico confirm the fact that the perceived desirability and feasibility have a significant and positive effect on the intentions to start their own company. On one hand, the empirical evidence obtained shows a heterogenic effect of the risk dimensions associated with entrepreneurship on the perceived desirability and feasibility in their behaviour. Therefore, it was found that the economic risk associated with entrepreneurship has a negative effect on the feasibility to start a business, but does not significantly influence the desirability of that behaviour. On the other hand, a significant effect from the risk related to health is not seen on desirability and feasibility, but the negative influence of personal risk is empirically supported for both variables. Finally, the results obtained related to social and time risk are contradictory. Social risk negatively influences entrepreneurship desirability, but a positive effect is observed on the feasibility to create a business. For its part, the empirical evidence obtained does not support any effect of the time risk on the perceived feasibility of starting a business, but there is a positive on entrepreneurship desirability. These results, which are contrary to the traditional concept of risk as a barrier to entrepreneurship, are justified by the vocational nature of this behaviour and by the social sacrifices that are sometimes necessary to be able to make a business work.     

浅谈中央空调循环水系统水处理的重要性和必要性

中央空调循环水处理是通过中央空调的循环水系统来实现的,这样的水处理之所以重要主要是因为没有经处理的水会使管道腐蚀、结垢等,使得设备的使用寿命大大缩短。