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91.
土地利用变化驱动力多尺度因素的定量影响分析 总被引:1,自引:0,他引:1
研究目的:揭示多尺度土地利用变化研究中尺度因素对驱动力的定量影响。研究方法:构建Logistic回归模型和二分类反应变量两水平Logistic回归模型,分别基于面向尺度对比的多尺度回归分析和基于系统观点的多水平模型分析两个角度,探讨多尺度土地利用变化核心驱动力及其定量影响关系,并对两类模型的分析结果进行对比分析。研究结果:面向尺度对比的多尺度回归分析法能够从更为微观的角度揭示各个尺度层级上地类变化的核心驱动因子,而基于系统观点的多水平模型分析方法则能够更好地顾及尺度因素的定量影响。研究结论:多水平模型分析方法揭示的各个地类的核心驱动因子集与多尺度回归分析法推导的对应地类的核心驱动因子集之间呈现子集关系,两者在多尺度土地利用变化驱动力的研究方法上能够形成互补。 相似文献
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以浙江电网企业转型现代能源综合服务的具体战略与发展规划为研究背景,针对能源综合服务系统的运行规划目标,开展基于运行规划的能源综合服务系统能效管理研究。从系统工程的视角出发,以能源流为纽带,基于多尺度能源系统建模方法,构建了能源综合服务系统模型,并结合系统综合能效,采用粒子群优化算法来优化系统各设备单元的运行策略,以实现基于运行规划的最优能效管理。通过能源综合服务系统模型计算表明,大规模清洁能源和可再生能源的接入,可以明显提高系统综合能效;随着区域用户总冷量和/或总热量需求占总电力需求的比值增大,系统最优综合能效逐渐增大;与使用内燃机、燃气轮机及汽轮机为原动机的热电联产系统相比,使用燃料电池为原动机的热电联产系统可以使能源综合服务系统综合能效更优。 相似文献
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Garry Chick Chih-Kuei Yeh Chi-Ming Hsieh So Young Bae Svitlana Iarmolenko 《Leisure Sciences: An Interdisciplinary Journal》2016,38(5):402-423
The purpose of this study threefold: to determine whether a shared cultural model of the importance of a set of leisure activities to a good leisure life existed in urban Taiwan, the degree to which cultural consonance in leisure mediates the relationship between leisure constraints and leisure satisfaction, and the degree to which leisure satisfaction affects life satisfaction and self-rated health. Results indicate that a cultural model of the importance of leisure activities to a good leisure life existed among sample members. Second, higher levels of self-reported participation in leisure activities that are culturally agreed upon as more important for a good leisure life are more strongly associated with leisure satisfaction than are activities culturally agreed upon as less important. Finally, leisure satisfaction strongly predicts both life satisfaction and self-rated health. 相似文献
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新能源汽车的发展进入重要战略机遇期,基于用户评论的文本挖掘能够明确消费者需求、把握产品优劣特性,从而促进市场良性发展。聚合多家汽车网站关于新能源汽车的在线评论数据,在情感倾向分类基础上进行深度挖掘。结果显示:用户对新能源汽车的整体情感倾向呈积极;用户在新能源汽车的空间舒适性、外观和驾驶感受等方面积极体验较高,尤其对其代步出行、外观及空间、节能环保等方面认可度高;而消极体验主要体现在续航能力、舒适性、内饰做工和硬件设施等方面,尤其对内饰做工、电力消耗等方面颇有微词;进一步的LDA主题分析发现,新能源汽车的加速动力、外观、操控、空间、节能环保等优势特征显著,但其智能网联、内饰做工、充电基础设施等方面劣势较为突出。基于此,提出针对性的新能源汽车生产及营销策略优化建议,以期有效提升用户体验,助益新能源汽车产业发展。 相似文献
98.
Chien-Cheng Chen Ying-Chun Liu 《International Journal of Human Resource Management》2013,24(15):2894-2910
This study investigates (1) the relationship between employees’ trait of negative affectivity (NA) and workplace deviance and (2) the moderating role of ethical climate in the above relationship. Data was collected from 310 employees in 40 Taiwanese companies, and hierarchical linear modeling was used to test the hypotheses. Results show that NA was positively related to workplace deviance. In addition, the rules climate weakened the relationship between NA and workplace deviance, and both the instrumental climate and the caring climate strengthened the relationship between NA and workplace deviance. Managerial implications and future research directions are also discussed. 相似文献
99.
Erin Morris Gerard T. Kyle Kenneth E. Wallen James Absher 《Leisure Sciences: An Interdisciplinary Journal》2013,35(6):494-507
ABSTRACTThe effects of gender on involvement in high-risk recreation have received limited research attention despite mounting evidence suggesting the learned interactions between people and places likely vary for men and women. The purpose of this study was to provide insights into how gender influenced the motivation-involvement relationship among whitewater recreationists on a Wild and Scenic River in California. Our results revealed the motivations of Risk, Escape, Learning, and Achievement/Stimulation positively influenced involvement in rafting activities. Although gender did not influence all dimensions of involvement, we found that identity expression varied between subgroups. Specifically, men were more likely to ascribe meaning to rafting than women because this activity allowed them to affirm and express their individual character. The implications emanating from this study advance theoretical understanding of the factors that influence enduring involvement and inform natural resource management decisions about maintaining the desired benefits of activities sought by nature-based recreationists. 相似文献
100.
ABSTRACTModeling multivariate time-series aggregate losses is an important actuarial topic that is very challenging due to the fact that losses can be serially dependent with heterogeneous dependence structures across loss types and business lines. In this paper, we investigate a flexible class of multivariate Cox Hidden Markov Models for the joint arrival process of loss events. Some of the nice properties possessed by this class of models, such as closed-form expressions, thinning properties and model versatility are discussed in details. We provide the expectation-maximization (EM) algorithm for efficient model calibration. Applying the proposed model to an operational risk dataset, we demonstrate that the model offers sufficient flexibility to capture most characteristics of the observed loss frequencies. By modeling the log-transformed loss severities through mixture of Erlang distributions, we can model the aggregate losses. Finally, out-of-sample testing shows that the proposed model is adequate to predict short-term future operational risk losses. 相似文献