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排序方式: 共有697条查询结果,搜索用时 15 毫秒
41.
基于PLC和变频器控制的毛条生产线   总被引:2,自引:0,他引:2  
某厂十多年前从法国引进一毛条生产线,由于设备老化,必须改造。本文叙述应用PLC和变频器技术对该生产线进行技术改造的技术设计思想。籍此说明对旧设备进行自动化技术改造的必要性和可行性。  相似文献   
42.
介绍了建筑工程中变形缝设置的特点,分析了变形缝标准图集在工程施工中的运用和存在的一些问题,介绍了在实践过程中对变形缝标准图集的探索和改进。  相似文献   
43.
农村集体资产管理关系着农村经济的发展,对于社会的稳定和谐也有着重要影响,乡镇政府应加强对集体资产的重视,平衡乡镇改革与资产管理之间的关系,分析农村集体资产管理中存在的一些问题,结合自身的特点,采取有效的措施来促进其发展,加快城镇化农村集体资产管理显得尤为重要。  相似文献   
44.
高维环网上的一种可扩展的全交换算法   总被引:1,自引:0,他引:1       下载免费PDF全文
刘刚  顾乃杰  任开新  熊焰 《电子学报》2005,33(9):1723-1728
全交换在并行计算领域中有着大量而且重要的应用,例如FFT和矩阵运算等.本文提出了一种适合环网结构的全交换算法.算法中采用了新的网络划分技术及通信模式,使高维环网上全交换算法的通信量的主项达到了理论下限,这是已知的其他相关算法未能达到的,且其启动次数与通信量均优于现有的其他同类算法.本文所述的算法并不要求环网每一维上的处理器结点数目是2的方幂或某一个数的平方.最后,该算法简单规范,易于硬件高效实现.  相似文献   
45.
Controllable actuation and coordinating motion of artificial self‐propelled micro/nanomotors to mimic the motile natural microorganism systems are of great significance for constructing intelligent nanoscale machines. In particular, inorganic oxide particles have shown considerable promise in implementation of synthetic micro/nanomotors, due to their unique features and active response to environmental stimuli. This work critically reviews the recent progress in inorganic oxide‐based micro/nanomotors and focuses on their propulsion response to chemical and physical stimuli, especially emphasizing and discussing operating principles in the single engine, adaptive navigation under composite‐driven powers, and intriguing collective behaviors. The impact of oxide structure, multiple fields in motion controllability, and interaction between grouped micro/nanomotors are explored. Practical applications of individual and assembled micro/nanomotors in environmental and biomedical fields are demonstrated, including the removal of pollutants, drug delivery, cancer therapy, and in vivo imaging. Finally, current challenges for the development of novel micro/nanomotors and possible constraints toward the defined structure and accumulated toxicity are discussed along with future opportunities and directions. Owing to their facile synthesis, impressive physicochemical performances, high biocompatibility, and versatile actuations, it is expected that the association of inorganic oxides with micro/nanomotors will bring new and unique capabilities to the field of active matter.  相似文献   
46.
Fire-fighters, paramedics, and emergency medical technicians routinely confront potentially traumatic events in the course of their jobs. The mediation role of coping strategies and collective efficacy in the relationship between stress appraisal and quality of life was examined (compassion satisfaction, compassion fatigue, and burnout) in a correlational study. Participants were 463 Italian rescue workers (fire fighters and different categories of emergency health care professionals). Participants filled out measures of stress appraisal, collective efficacy, coping strategies, and quality of life. The results showed that emotion and support coping, self-blame coping, and self-distraction mediated the relationship between stress appraisal and compassion fatigue. Moreover, collective efficacy, self-blame coping, and religious coping mediated the relationship between stress appraisal and burnout. Finally, collective efficacy, self-blame coping, and problem-focused coping mediated the relationship between stress appraisal and compassion satisfaction. Cognitive restructuring and denial did not mediate the relation between stress appraisal and any of the quality of life dimensions. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
47.
Collective intelligence has been an important research topic in many AI communities. With The big data phenomenon, we have been facing on many research problems on how to integrate the big data with collective intelligence. This special issue has selected 9 high quality papers covering various research issues.  相似文献   
48.
Metallochloronitrides are layered conductors that have recently been found to superconduct at critical temperatures up to T c 26 K. It is known that the electron–phonon interaction is small in these systems, so that the conventional pairing mechanism through exchange of phonons is unable to provide for such high T cs. We show that the dominant contribution to the pairing interaction in these materials comes from the exchange of low-energy collective modes, specific to layered conductors. The existence of such acoustic plasmons results from the incomplete screening of the Coulomb interaction perpendicular to the conducting planes which expresses itself in the dynamical nature of the screened Coulomb interaction.  相似文献   
49.
In the present research, we examine whether leader's self-sacrifice positively influences followers' self-esteem and whether followers' identification with the collective plays a role in this process. It was predicted that leader self-sacrifice would influence followers' self-esteem, but particularly so when followers exhibited strong (vs. weak) collective identification. Results from an organizational survey showed that leader self-sacrifice and collective identification interacted in predicting follower self-esteem, such that followers' self-esteem was higher when they identified strongly with the collective and when the leader was self-sacrificial (vs. self-benefiting). An experimental scenario study replicated this interactive effect between collective identification and leader's self-sacrifice on followers' self-esteem and also showed that this effect was (at least partly) mediated by followers' perceptions of whether the leader respected and valued the group. Implications with respect to the relationship between self-sacrifice and self-esteem are outlined, and possible integrations of leader self-sacrifice, identity, and empowerment are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
50.
在莫言中前期的小说中,存在着大量对动植物形象的描绘,并且作往往将之作为神化和崇拜的对象,这种动植物崇拜现象体现了长期积淀在人们集体无意识中的图腾情结。对莫言而言,这种情结的形成还与地域化、根性认同和生活经历有关。  相似文献   
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