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21.
On rough terrain, excessive wheel slippage is easily generated by changes of surface conditions such as soil types and geometries. It induces considerable loss of wheel traction and battery energy. To prevent this, wheeled robots should consistently recognize the current situation generated between wheel and surface. And also wheeled robots are required to optimally control wheel motion in limited wheel traction and battery capacity. Therefore, this paper proposes a novel wheel control algorithm based on slip optimization of traction and energy, which is adaptive to change of surface condition. Proposed wheel control algorithm is called Traction-Energy Balancing Adaptive Control (TEB) in this paper and TEB assigns optimized rotation speed to each wheel by observing wheel slip ratio which is a key parameter of TEB. As functions of TEB, TEB is largely divided into three main parts; (1) slip optimizer (2) slip controller (3) SC-compensator. In the slip optimizer, two optimal slip models were derived as a function of slip ratios regarding maximum traction and tractive efficiency using experimental data about wheel-terrain interaction in three types of soil (grass, gravel and sand). And the optimal slip models were employed in order to determine a desired slip value of wheel with observation of a change in actual robot velocity as control input in the slip controller. For optimal slip control, the proposed slip controller is based on conventional PID controller with compensating disturbance in the controller (SC-compensator) which occurs by change of surface shapes. In the SC-compensator, radial function networks (RBFN) was applied in the slip controller and RBFN was of help to readjust previously set PID gains depending on occurred slip error. Finally, TEB was experimentally verified by controlling a real robot having four wheels on various terrain types. 相似文献
22.
23.
Peter L. Kelley 《Zygon》2018,53(2):642-662
The income and careers that come with building wind turbines have become a lifeline for many factory towns and farming communities. Generating electricity from the wind puts increasingly cheap power on the grid, saving consumers billions a year. And it is one of the biggest, fastest, cheapest ways to reduce carbon pollution, reducing the threat of climate change. Yet as wind farms have rapidly spread to forty‐one states, their developers must make their case anew with each community that hosts them. Facts matter, but so do empathy, honoring deep connections to neighbors and landscape, and developing mutual respect. Successful wind farm developers listen first for shared values and speak with inclusive language, to communicate with potential opponents across divides of misunderstanding and motivate local residents to adapt to and benefit from change. 相似文献
24.
服务型领导对员工建言行为的影响:领导-成员交换和学习目标取向的作用 总被引:1,自引:0,他引:1
通过对191名员工及其领导的配对问卷调查,探讨了服务型领导对员工建言行为的作用机制。结果发现:(1)服务型领导对员工建言行为有积极影响;(2)服务型领导通过领导-成员交换的中介效应影响员工建言行为;(3)员工的学习目标取向对领导-成员交换与建言行为之间的关系具有调节效应,即员工的学习目标取向越强,领导-成员交换对建言行为的影响越大;(4)学习目标取向调节了领导-成员交换对服务型领导-建言行为的中介作用。 相似文献
25.
Mary Evelyn Tucker 《Zygon》2015,50(4):949-961
With the challenge of communicating climate science in the United States and making progress in international negotiations on climate change there is a need for other approaches. The moral issues of ecological degradation and climate justice need to be integrated into social consciousness, political legislation, and climate treaties. Both science and religion can contribute to this integration with differentiated language but shared purpose. Recognizing the limits of both science and religion is critical to finding a way forward for addressing the critical challenges of climate change. How we value nature and human–Earth relations is crucial to this. We need a broader environmental ethics in dialogue with the science of climate change. 相似文献
26.
Sexual harassment is a serious societal issue, with extensive economic and psychological consequences, yet it is also an ill-defined construct fundamentally defined in terms of subjective perception. The current work was designed to examine the ways in which individual differences between people are systematically related to different perceptions of sexual harassment scenarios, as well as reasoning about those harassment situations. Participants (N = 460) read several possible harassment scenarios and rated how uncomfortable they would find them. They then also evaluated a quid pro quo sexual harassment situation in terms of their interpretation of it as a threat or a social exchange and completed a deductive reasoning task about the same situation. Females and individuals with slow life history strategies were more uncomfortable with potential harassment situations and were more likely to interpret the quid pro quo scenario as a threat. Further, interpreting the scenario as a threat was associated with poorer performance on the deductive logic task, compared to those who interpreted the scenario as a social exchange. 相似文献
27.
ABSTRACTEngaging publics in participatory events has become a central means to introducing lay people's voices into processes of technoscientific innovation and governance. However, little attention has been paid to the role of aesthetics, especially in terms of opening up potential ways of critically and creatively engaging with technoscientific matters of concern. The terms semblamatic and matters of potentially are proposed as addressing this dimension of aesthetics. Drawing on practice-based design research, a probe workshop with members of energy communities was implemented. Three probe exercises served to open up potential re-articulations of such core themes as energy, communities and futures. Our goals were to examine the whether such probes enabled semblamatic responses and the emergence of matters of potentiality. Findings were mixed. The continued retention of standard meanings of these core themes suggested that such events can be anaesthetic, blunting access to the semblamatic aspects of engagement. Conversely, there was some opening up in which the core themes were creatively re-articulated. The present perspective, with its three novel terms - semblamatic, matters of potentiality, and anaesthetic - might prove useful in alerting scholars to the complex role of aesthetics in the methodological and analytic practices entailed in engagement with publics. 相似文献
28.
Giovanni Valdrè Massimo Antognozzi Alex Wotherspoon Mervyn J. Miles 《Philosophical Magazine Letters》2013,93(9):539-545
We report on the specific interaction between DNA and some mica-family minerals and other layered silicate structures. The interaction depends on mineral surface's crystallography, chemistry and potential. These properties are responsible for a remarkable variety of adsorption mechanisms and can be used to modulate surface self-assembly and nanopatterning of DNA. The controlled deposition of DNA onto non-conductive mineral regions with atomically flat boundaries has very attractive applications in nano-biotechnology (for example, microelectronics, microarrays and sensors). In addition, the extreme affinity discovered for some mineral surfaces, together with their ability to organize the DNA molecules, could be an indication of their catalytic potential. It may also have had relevance in the prebiotic environment, with important implications for the earth and life sciences. 相似文献
29.
赵驰 《医学与哲学(人文社会医学版)》2013,34(10):73-76
长期以来,对心衰和心衰机制的认识一直存在争议,所以心衰的治疗一直是国内外心血管领域中的一个挑战.为了澄清心衰机制的内涵,本文用弗兰克-斯塔灵定律以及能量守恒定律作为重建心脏理论以及心衰机制的依据,论证了心脏的做功是从动能向势能,又从势能向动能的转换过程.并根据临床事实等来证实心脏舒张是在作功,与收缩期作功是等同的.没有心脏的舒张就没有心脏的收缩,心脏功能下降实际上是舒张与收缩功能同时的下降.不存在有收缩功能正常的舒张功能下降.心功能的判定标准不能采用射血分数,而应该采取能量消耗的定量方法来测定. 相似文献
30.
Interpersonal trust is a vital component of social relationships. In this study the roles of parental attachment, perceived similarity of trustee to self, and social exchange processes in trust development were investigated longitudinally with randomly assigned, same-sex undergraduate roommates during emerging adulthood. A total of 214 first-year students completed weekly self-report measures during the first 5 weeks of the fall semester. Perceived similarity measured the second week and social exchange with roommates across the 5 weeks predicted participants’ trust in their roommate, with social exchange mediating the relation between perceived similarity and trust. Results highlight interrelations of social exchange and trust in established relationships. 相似文献