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251.
We propose a new approach to the multivariate analysis of data sets with known sampling site spatial positions. A between-sites neighbouring relationship must be derived from site positions and this relationship is introduced into the multivariate analyses through neighbouring weights (number of neighbours at each site) and through the matrix of the neighbouring graph. Eigenvector analysis methods (e.g. principal component analysis, correspondence analysis) can then be used to detect total, local and global structures. The introduction of the D-centring (centring with respect to the neighbouring weights) allows us to write a total variance decomposition into local and global components, and to propose a unified view of several methods. After a brief review of the matrix approach to this problem, we present the results obtained on both simulated and real data sets, showing how spatial structure can be detected and analysed. Freely available computer programs to perform computations and graphical displays are proposed.  相似文献   
252.
本文论述了人的全面发展是个体发展与整体发展的统一,个体的发展是整体发展的基础,整体发展是个体发展的必然结果.提出了人类通过实践、创新、发展生产力,提高人的素质,促进人的全面发展.  相似文献   
253.
Studies of adsorption of cadmium by free bacterial and free actinomycete cells, alginate beads and immobilised bacterial or actinomycete cells in alginate beads were performed in ultrapure water. The immobilisation in alginate beads allows the survival of the microorganisms in non-ideal conditions. Here, we found the following affinity for the cadmium ion: R25 free cells<alginate beads<R25 immobilised cells<ZAN 044 immobilised cells<ZAN 044 free cells, obtained with the b Langmuir parameter. The maximum uptakes gave the series: ZAN 044 free cells<ZAN 044 immobilised cells<R25 free cells<alginate beads<R25 immobilised cells.  相似文献   
254.
在高温实验基础上,提出一种建立材料高温塑性成形全过程的唯象本构关系的方法,获得42CrMo及T3两种典型材料的热塑性加工过程应力-应变本构方程。为材料成形工艺及数值模拟提供不可缺少的基本保障条件。  相似文献   
255.
This paper describes the roles that dose-response andbiogeochemical-cycle models play in the comparative and integratedassessment of several atmospheric issues. The two approaches aredescribed briefly, as they are commonly used, and as they might beapplied when multiple stressors and receptors, and when interactingcycles, respectively, are involved. Examples are drawn from thecarbon and sulfur cycles to demonstrate how knowledge of a cycleprovides a useful link among various current pollution issues. Possibleinteractions and some shortcomings of the two approaches are given,leading to suggestions for the appropriate use of the two tools forscientific analysis and policy development for the various air issues.  相似文献   
256.
The relationship of polycyclic aromatichydrocarbons (PAH) and smoke concentrationwas analysed at four different locations in Zagreb during theheating season. At two sampling sitessmoke pollution came primarily from domestic heating while theother two sites were under a directinfluence of traffic. At locations away from trafficcorrelations between smoke and PAH concentrationswere stochastically significant at 0.01 level. Takingbenzo-a-pyrene (BaP) as a PAH representative itwas shown that for these two locations the smoke/BaPrelationship can be presented with a singleregression line which can serve for rough assessment of BaPlevels in the air. The BaP concentrationof 10 ng/m3 – proposed by the German FederalEnvironmental Agency as orientation < mark (Lahman et al., 1984) – might be expected to occurat smoke levels 60 g/m3,and above this level it is recommended to start measuringactual concentrations of PAH.  相似文献   
257.
基于现有的埋地管道缺陷自漏磁场计算方法把缺陷处的磁荷假设为均匀分布,对于计算结果与实际检测存在较大误差的问题,通过采用ANSYS软件对管道缺陷进行有限元分析,根据材料力磁关系和磁荷理论,提出1种考虑磁荷实际分布的缺陷自漏磁场计算方法,并将该计算方法应用在某埋地管道磁记忆检测中。研究结果表明:该方法计算结果与实际值之间的峰值相对误差为6.9%,相对于现有方法16.4%的相对误差,准确度更高。研究结果有助于在管道磁记忆检测中,提高管道缺陷量化的准确性,对埋地管道缺陷非开挖识别与剩余寿命评价有重要意义。  相似文献   
258.
Despite being based on the premise of a dynamic interpersonal process, studies on leader–member exchange theory often fail to acknowledge its dyadic and dynamic nature. We discuss how the interpersonal affect dynamics literature—and particularly its focus on the emergence of relationship patterns—may advance research on leader–follower interactions.  相似文献   
259.
Attributions are causal explanations made by individuals in response to important, novel, and/or unexpected events. Numerous attribution theories have examined how people use information to make attributions and how attributions impact an individual's subsequent emotions and outcomes. However, this research has only recently considered the implications of dyadic‐level attributions (i.e., relational attributions), particularly in the context of leader–follower relationships in organizations. Therefore, the purpose of this theoretical paper is threefold. First, we integrate research on attributional biases into the research on relational attributions. Second, we integrate and extend attribution theory to consider the implications of convergent and divergent internal, external‐person, external‐situational, and relational attributions for leader–member exchange (LMX) quality, relationship work, self‐work, and conflict. Third, we make the implicit ranking of attribution combinations and the resultant levels of relationship work explicit. In doing so, we contribute to attribution theory and research by proposing how attribution combinations produce positive and negative outcomes that are both intrapersonal and interpersonal. Further, we contribute to the LMX literature by explicating how leader–follower attribution combinations influence relationship quality.  相似文献   
260.
Despite the importance of apology in reconciling interpersonal transgressions, little research has focused on the people engaging in the behavior. Why do transgressors apologize in the workplace, and do apology motives shape transgressor perceptions of reconciliation? We conducted three field studies using qualitative and quantitative methodologies to examine these questions. In Studies 1 and 2 (total N = 781), we identified four distinct apology motives—self‐blame, relational value, personal expedience, and fear of sanctions—and developed self‐report scales to measure the motives. In Study 3 (N = 420), we examined relations between apology motives and transgressor perceptions of victim forgiveness and relationship reconciliation through the lens of motivated cognition. We found that apologizing due to self‐blame, relational value, and personal expedience increases perceptions of victim forgiveness, whereas apologizing due to fear of sanctions decreases perceived forgiveness. Moreover, mediation analyses revealed that motives indirectly influence transgressor perceptions of relationship reconciliation through perceived forgiveness. Taken together, our research presents a novel multidimensional perspective on apology‐giving in the workplace, suggesting that why transgressors apologize can affect their perceptions of reconciliation. Overall, our research highlights the need to incorporate transgressor cognitive and motivational processes into reconciliation research.  相似文献   
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