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121.
Predictions of the model of van Schaik (1989) of female-bonding in primates are tested by systematically comparing the ecology, level of within-group contest competition for food (WGC), and patterns of social behaviour found in two contrasting baboon populations. Significant differences were found in food distribution (percentage of the diet from clumped sources), feeding supplant rates and grooming patterns. In accord with the model, the tendencies of females to affiliate and form coalitions with one another, and to be philopatric, were strongest where ecological conditions promoted WGC. Group fission in the population with strong WGC was “horizontal” with respect to female dominance rank, and associated with female-female aggression during a period of elevated feeding competition. In contrast, where WGC was low, females’ grooming was focused on adult males rather than other females. Recent evidence suggests that group fission here is initiated by males, tends to result in the formation of one-male groups, and is not related to feeding competition but to male-male competition for mates. An ecological model of baboon social structure is presented which incorporates the effects of female-female competition, male-male competition, and predation pressure. The model potentially accounts for wide variability in group size, group structure and social relationships within the genus Papio. Socio-ecological convergence between common baboons and hamadryas baboons, however, may be limited in some respects by phylogenetic inertia. Received: 22 April 1994/Accepted after revision: 9 December 1995  相似文献   
122.
企业安全管理群体行为与动力理论探讨   总被引:7,自引:1,他引:7  
企业职工个体总是存在于某个群体之中 ,为了适应群体和群体环境 ,个体的安全行为与其单独行动时的行为有所不同。笔者首先讨论了群体的概念、特征和类型 ;然后给出了安全管理群体行为的概念 ,即群体行为主体在该群体组织内进行的与安全生产有关的活动就是安全管理的群体行为 ,以及安全管理群体行为的特征(群体行为的规律性、群体行为的可测量性、群体行为的可划分性、群体行为对个体的影响性 ) ;最后论述了安全管理中的群体动力理论和群体动力对职工安全行为的影响 ,包括对安全绩效的社会促进与促退作用、安全社会标准化倾向、群体压力和从众行为等  相似文献   
123.
苏北海州群云台组上段变火山岩富含碱性长石(60-70%)和钾长石(35-60%),黑云母为富铁黑云母,部分火山岩含霓辉石、萤石等.其岩石地球化学特征:高硅(SiO_2>6.41%),富碱(Na_2O+K_2O8.54%).高钾(K_2O4.52%),低铝(Al_2O_311.88%).贫钙、镁(CaO0.25%,MgO0.13%);富Nb、Zr、Y、Zn和Ga等元素;富REE、LREE和Eu强烈亏损.上述特征与世界和福建魁歧、浙江青田、江苏苏州、山东崂山等A型(或碱性)花岗岩的特征一致,为A型火山岩.其连云港市东部分布区是寻找与海相A型火山岩有关的Sn、W、Zn、Ph、Ag(Au)等华前型块状硫化物矿床和热液矿床的重要靶区.  相似文献   
124.
The emergence of unshared consensus decisions in bottlenose dolphins   总被引:1,自引:1,他引:0  
Unshared consensus decision-making processes, in which one or a small number of individuals make the decision for the rest of a group, are rarely documented. However, this mechanism can be beneficial for all group members when one individual has greater knowledge about the benefits of the decision than other group members. Such decisions are reached during certain activity shifts within the population of bottlenose dolphins residing in Doubtful Sound, New Zealand. Behavioral signals are performed by one individual and seem to precipitate shifts in the behavior of the entire group: males perform side flops and initiate traveling bouts while females perform upside-down lobtails and terminate traveling bouts. However, these signals are not observed at all activity shifts. We find that, while side flops were performed by males that have greater knowledge than other male group members, this was not the case for females performing upside-down lobtails. The reason for this could have been that a generally high knowledge about the optimal timing of travel terminations rendered it less important which individual female made the decision. This contribution is part of the special issue “Social Networks: new perspectives” (Guest Editors: J. Krause, D. Lusseau and R. James).  相似文献   
125.
我国桐油发展战略与对策   总被引:6,自引:0,他引:6  
桐油是我国的特产资源,其价值之高,用途之广,早已引起许多国家的重视;其化学结构之特殊,化学性质之活泼,引起许多化学工作者的兴趣,而致力于桐油化学科学的研究。我国种植油桐历史修久,远在公元前六世纪有文记载。新中国成立后,党 和政府非常重视,周总理曾亲自主持全国油桐工作会议,油桐得到了空前发展。  相似文献   
126.
127.
This study compared the actual and perceived social norms regarding road crossing behaviors, and aimed at uncovering a misperception of group norms. The basic notion underlying the study was that if children perceived the behaviors and attitudes of their friends regarding road crossing as more negative than they actually are, this might lead the children to adopt riskier behavior when crossing the road. The participants were comprised of 123 elementary school children (ages from 6 to 13; 78 boys - 65% and 42 girls - 35%) from Beitar-Ilit, a religious city in Israel. A questionnaire especially constructed for the study was administered to the participants. A t-test yielded a significant difference between the child’s own attitudes score and the perceived peers’ attitudes score. On average, children perceive their friends’ attitudes with regard to road crossing behaviors as being more negative compared to their own attitudes. A second t-test yielded a significant difference between the child’s own behavior score and the perceived peers’ behavior score. Children perceived the road crossing behavior of their friends as riskier relative to their own crossing behavior. A regression test revealed that the variables, perceived peers’ attitudes and perceived peers’ behaviors, contributed significantly to the explained variance: the more risky the perceived peers’ attitudes and behaviors with regard to road crossing, the more risky the child’s own behavior when crossing the road. It is hoped that an interventional educational program based on positive norms in the social group will encourage children to exhibit safe behavior in the roads.  相似文献   
128.
阐述了清洁生产的内涵,重点介绍了东风汽车公司清洁生产的成功做法和取得的成效。  相似文献   
129.
There is evidence that individuals in animal groups benefit from the presence of knowledgeable group members in different ways. Experiments and computer simulations have shown that a few individuals within a group can lead others, for a precise task and at a specific moment. As a group travels, different individuals possessing a particular knowledge may act as temporary leaders, so that the group will, as a whole, follow their behaviour. In this paper, we use a model to study different factors influencing group response to temporary leadership. The model is based on four individual behaviours. Three of those, attraction, repulsion, and alignment, are shared by all individuals. The last one, attraction toward the source of a stimulus, concerns only a fraction of the group members. We explore the influence of group size, proportion of stimulated individuals, number of influential neighbours, and intensity of the attraction to the source of the stimulus, on the proportion of the group reaching this source. Special attention is given to the simulation of large group size, close to those observed in nature. Groups of 100, 400 and 900 individuals are currently simulated, and up to 8,000 in one experiment. We show that more stimulated individuals and a larger group size both induce the arrival of a larger fraction of the group. The number of influential neighbours and the intensity of the stimulus have a non-linear influence on the proportion of the group arrival, displaying first a positive relationship and then, above a given threshold, a negative one. We conclude that an intermediate level of group cohesion provides optimal transfer information from knowledgeable to naive individuals.  相似文献   
130.
新时期的经济竞争,转向了以中心城市为核心的城市群综合实力的竞争.在运用SWOT分析法定性分析的基础上,引用QSPM矩阵,对影响滇中城市群一体化进程的内外条件做量化评价.结果表明,滇中城市群尚处于城市群发育的初期阶段.在其影响因素中,优势与劣势都很明显,机遇胜过威胁.从总体作用效能来看,滇中城市群发育的内部动力需要得到进一步强化,外部动力是难得的发展机遇,正在或将会成为滇中城市群成长的助推剂.  相似文献   
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