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激励,即调动积极性。西方国家的企业提倡并重视调动员工的积极性。常用的激励方式及其特点如下: 1、需求层次 需求层次理论是由马斯洛研究提出的。他把人的需求划分成通常所讲的五个层次,即“生理需求”、“安全需求”、“归属需求”、“尊重需求”和“自我实现需求”。依次由低向高,已满足了的需求不再具有激励效应。在个体员工转向更高层次  相似文献   
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Zheng  BS 束龙仓 《世界地质》1991,10(1):163-165
地方性氟中毒已被世界许多国家和地区所熟知,它也危及着许多中国居民的健康,到目前为止,关于氟中毒的实例报道大都起因于饮用高氟浓度的地下水。然而,根据作者的调查,中国西南部居民中发现的氟中毒情况是由于在室内烧煤而造成,食物和空气污染而至。作者对这一类型的氟中毒区,从致病途径和规律等方面进行系统的环境特征研究。  相似文献   
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This study examined perceptions of the impacts of the antinatalist (OPP) and pronatalist (NPP) policies in Singapore. Data were obtained from a sample of 209 men and 280 women under 45 years old who lived in Ang Mo Kio New Town in the center of the island. Findings indicate that 53.4% of women said that fertility decisions were joint ones. 50% of women and 65% of men said that family size was jointly determined. Over 70% were aware of the OPP "stop at 2" policy. Those who gave accurate, detailed knowledge were mostly over 35 years old. Knowledge of OPP did not vary by education, but did vary by awareness of incentives and disincentives. 45.4% of women believed that OPP was a necessary state policy; 25.4% did not. 36.4% thought that OPP was fair; 28.3% did not. 60.3% of women said that OPP did influence family size in society, but 63.8% said it did not influence their individual family size. Finances, education, and child care were explanatory factors in individual planning. OPP is viewed as a successful policy not because of ideology, but because of the value placed on improved socioeconomic standards. 58.2% of women and 55.5% of men knew the details about the NPP. 51.9% of women said the NPP would encourage larger family size, but 87.8% said it would not affect them personally. Findings suggest that personal freedoms and public ideology are not binary, public-private concepts in fertility decision making.  相似文献   
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A uniform terminology on bioinvasions: a chimera or an operative tool?   总被引:4,自引:0,他引:4  
A consensual set of definitions regarding bioinvasions is essential in order to facilitate discourse among the science, policy and management communities dealing with the issue. Considering both the mode of entry and the extent of the impact of an alien species into a new environment, a set of key terms is proposed as an operative tool for marine scientists.  相似文献   
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Analyses of living foraminiferal and environmental parameters near an outfall at Mar Grosso Beach (Laguna, SC, Brazil) demonstrate its usefulness as indicators of domestic sewage pollution. The low species diversity may be due to sand accumulation in the central part. Higher diversity was noted closer to the mouth of Laguna estuarine system where reduced salinity and higher temperatures indicate freshwater influence, suggesting a relationship between increased diversity and greater availability of terrestrial food. On the basis of foraminiferal diversity and average coliform count the higher values are closer to the mouth of the estuarine system and under the influence of the outfall. Due to the effect of local hydrodynamics, the particulate organic waste derived from the outfall does not settle down locally, and thus, do not accumulate nearby. Our hypothesis is that the fine material derived from the outfall is accumulating on the southwestern and northwestern parts of the beach.  相似文献   
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考虑土的成层性,假定桩周成层土弹性模量的不同不影响桩中性点位置,应用弹性理论和桩土位移协调条件及边界条件,推导了路堤荷载下复合地基加固区桩及桩周土压缩量计算的解析式,同时得到了各层土范围内桩、桩周土竖向应力及桩侧剪应力的表达式,并利用有限元分析了桩周土弹性模量的变化对桩中性点位置的影响规律,验证了假定。结果表明:使用该计算方法分析路堤荷载下复合地基加固区内桩和桩周土的变形,计算结果与有限元及实测结果比较接近,满足工程计算精度要求,能为类似地基土成层分布工程沉降分析提供有益参考。  相似文献   
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