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151.
During the past 20 years, findings have indicated that nature plays an active role in helping people recover from stress and fatigue. Two of the most cited theories in this field are Rachel and Stephen Kaplan's theory of recovery from Directed Attention Fatigue in nature and Roger Ulrich's theory of aesthetic and affective responses to natural environments and stress recovery. One aim of the present study is to test whether being outdoors in a green recreational environment causes people to be more focused, compared to being in a room indoors (in line with hypotheses suggested by the Kaplans). Another aim is to test whether people experience stress reduction, i.e. as evidenced by changes in blood pressure and heart rate, if they are placed in an environment with many green elements (in line with hypotheses suggested by Ulrich). The overall study design is that of an intervention study. Fifteen elderly persons living at a home for very elderly people participated. Their powers of concentration, blood pressure and heart rate were measured before and after an hour of rest in a garden or in an indoor setting. Seven elderly people were randomly chosen to have their first series of tests in a garden, while eight elderly people had their first series of tests indoors. The results indicate that powers of concentration increase for very elderly people after a visit to a garden outside the geriatric home in which they live, compared to that after resting indoors in their favourite room. The results did not show any effects on blood pressure or heart rate. It is suggested that having a one-hour rest outdoors in a garden setting plays a role in elderly people's powers of concentration, and could thereby affect their performance of activities of daily living. One important factor in this study was that both the outdoor environment and the indoor environment at the home were highly valued by participants.  相似文献   
152.
This review paper contends that by paying attention to the quality of life issues raised by older people, planners may promote better places for all. Recent research in the UK that asked older people to identify quality of life criteria revealed that health, income, social networks, community participation, information, activities, home, neighbourhood and mobility are key areas where old age can be enriched. The paper argues that of these, home, neighbourhood and mobility are paramount for four reasons. Firstly, older people are seen as situated, even fixed, in domestic environments; secondly, society has responded to later life by creating age-segregated spaces; thirdly, lessening mobility may increase the importance of the local arena and fourthly the interplay between the self and the environment underpins or undermines independence. The significance of place means that planners, even more than other professionals, need to be age aware. Drawing on recent national and international research this paper contemplates what a more age-friendly place might be like and considers how issues of age can interact with the broader planning agendas of sustainability, cohesion and liveability to create places that promote well-being for every member of the community.  相似文献   
153.
The numbers of English public houses or “pubs” have reduced significantly in the last two decades. Politicians have called on the planning system to resist their closure but, at the same time, demand further controls over high-street bars. This paper explores the reasons for the decline and the rationale for supporting the continuation of the “traditional” English pub. Using evidence drawn from a wider study of the relationships between places and youth drinking cultures, the paper discusses young adults' use of pubs. While recognising the adverse effects of heavy drinking, arguments are put forward in support of the traditional pub as a site for restrained and responsible social interaction for young adults. The paper discusses the issues this raises for the UK planning system in the context of responsibilities for social sustainability and public health.  相似文献   
154.
朱昆 《中外建筑》2013,(7):143-145
本文研究医疗类建筑环境的设计思路.通过积极环境的塑造来满足相关患者心理和生理上的诉求,从而为病人痊愈提供额外帮助。积极环境蕴藏着更多正能量,应该成为此类建筑着重考虑的因素。  相似文献   
155.
异型深盲孔结构的加工是深盲孔结构加工领域的难题。针对一种具有异型深盲孔结构的零件,设计了一种具有导向功能的展开式刀具。详细叙述了展开式刀具的运动原理、结构特点、装配方法,并进行了工艺切削实验,表明展开式刀具设计合理,能够满足这类异型深盲孔结构的加工需求。  相似文献   
156.
采用盲孔法测量汽轮机转子近表面的残余应力,并与切环法进行比较。结果表明:不同加工阶段,汽轮机转子表面的残余应力大小及分布是不同的;盲孔法更能真实地反映汽轮机转子近表面的残余应力状况;盲孔法测量残余应力,破坏性小,操作便捷,测量精度高。  相似文献   
157.
为提高P91钢焊接接头蠕变超声检测灵敏度,提出一种相对性的超声检测信号处理方法。该方法使用未发生蠕变的P91钢焊接接头的检测信号生成零蠕变特征空间,将任意检测信号向该空间投影,以投影残差能量与原信号总能量的比例表征检测目标偏离零蠕变状态的程度,比例越高,则表明蠕变损伤越严重。推导了该方法的一般性数学表达,并提出利用盲源分离算法实现该方法的线性化处理。利用不同蠕变程度的P91钢焊接接头试块对该方法进行了验证试验,结果表明,与常规超声方法相比,该方法具有更好的蠕变检测能力。由于该方法为相对性检测,零蠕变特征空间的完备性对检测结果的准确性具有较大影响。该方法以评价检测目标偏离标准特征空间的程度为核心,因此对其他损伤也具有检测能力。  相似文献   
158.
云南五里冲水库是我国在岩溶地区利用盲谷采用以灌浆为主,结合堵、截进行防渗处理,首次建成的水深超百米的无坝中型水库.帷幕灌浆工程量21.6×104m,单层帷幕深160m,地下溶洞内建造了高100.4m,长50m,厚2.0~2.5m的钢筋混凝土防渗墙;在岩溶塌陷体内用高压灌浆建造帷幕.  相似文献   
159.
瞬变电磁法浅层探测技术   总被引:2,自引:1,他引:1  
从理论上推导发射电流关断时间对瞬变电磁法勘探结果的影响,给出均匀半空间大地模型重叠回线互阻抗计算方法,分析阶跃关断与线性关断早期瞬变响应的区别,讨论了线性非零关断瞬变电磁法发射信号对浅层探测结果的影响。利用IGBT(绝缘栅双极型晶体管)实现瞬变电磁法发射电路,减小发射机关断时间,使之接近理想的阶跃函数,消除非零关断的影响,解决了加大发射电流与快关断的矛盾。实验结果表明,减小发射电流关断时间,可以提高瞬变电磁浅层勘探结果分辨率,减小瞬变电磁法勘探盲区。  相似文献   
160.
用于数字电视的盲均衡技术研究   总被引:3,自引:3,他引:0  
对目前在接收端采用均衡技术时常用的CMA算法和子空间算法的原理和性能进行了详细的讨论和说明,并给出各自的适用场合.  相似文献   
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