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51.
设计并实现了一种基于单片机的家居安防远程通信控制系统,主芯片采用凌阳16位单片机,利用传感器和GPRS模块技术,通过手机短信的方式了解家用电器所处环境的温度情况;采用语音识别系统和传感器实时监测家庭安全状况,若有异常,系统会及时发送短信通知主人;利用单片机控制固态继电器并通过GPRS模块远程启动家用电器。设计引入手机短信,通过短信来远程控制家用电器的使用以及自动接收来自家庭安防的各种信息,给人们的家居生活带来便利性和时效性。给出系统总体设计方案、各子系统硬件电路实现和软件设计,并对系统的关键技术进行说明。  相似文献   
52.
国内外土壤种子库研究情况对比分析   总被引:1,自引:0,他引:1  
摘要:土壤种子库是植被更新和生态恢复的自然来源。对生物多样性维护和植被的演替过程具有重要作用。通过查阅近年来国内外发表的关于土壤种子库的代表性文献,运用文献分析与管理软件EndnoteX3、Refviz和Excel数据处理软件对该领域的国内外研究情况进行了分析。同时,对国内外研究领域的扩展、土壤种子库的鉴别方法、土壤种子库的个体特征及群落结构的变化、土壤种子库的研究内容进行了系统对比,最后提出国内外对土壤种子库研究存在的问题,并就这些问题提出展望,为今后土壤种子库的研究工作提供了参考策略。  相似文献   
53.
The growing interests in “local food” in recent years in public discussions, research and practice highlight its significant importance as a part of overall food system. This research compares spatially local food production potential of home gardens in nine residential neighbourhood case studies with varying physical densities at a local scale using geographic information systems and mathematical methods. This paper develops a “local food energy model” for measuring sustainability potential of growing local food mainly vegetables in the home gardens. The outcomes indicate that potential of the home gardens in supplying vegetables demand as a share of total dietary energy would depend on the morphological characteristics of urban forms, total resident population, total food demand and other related factors. Local food production in the home gardens could meaningfully contribute towards building a sustainable food future.  相似文献   
54.
Urban policymakers and sustainable food activists have identified urban agriculture as an important strategy for confronting a host of urban problems, including food insecurity, health disparities, access to urban green space and community economic revitalisation. Much recent work on urban agriculture has examined community and school gardens, but little research has been undertaken on home gardens as a solution to urban problems. This article examines a home-gardening programme in San Jose, California, La Mesa Verde, asking whether some of the benefits found in community gardens can be found in home gardens. Specifically, we look at financial, health and community benefits, examining the potential of home gardens to become forces for broader social change. We ask whether gardens can become agents of cultural preservation, self-determination, particularly for recent immigrants who use these spaces to build identities and work towards collective action and self-determination.  相似文献   
55.
实现乡村旅游可持续发展需要正确把握的七个关系   总被引:7,自引:0,他引:7  
乡村旅游可持续发展的两个基本标准是:保护乡村资源,延续历史文脉;保障经济效益,延长生命周期。作者以此为出发点,从实践中总结出了实现乡村旅游可持续发展需要正确把握的七个关系:即乡村旅游与城市旅游之间的关系、大力发展乡村旅游与发展机遇的关系、市场主导与政府引导之间的关系、旅游开发与生态和历史文化保护的关系、公共利益与个体利益之间的关系、宣传造势与乡村接待能力之间的关系、“农家乐”与“乡村旅游”的关系。  相似文献   
56.
This study investigates the impact of a refurbishment of two communal spaces —lobby and recreation room— of a care home in the Netherlands on residents’ subjective well-being. The refurbishments aimed to improve the aesthetic appearance of both spaces and to offer residents more possibilities for controlled interaction. Data were collected by means of pre- and post-intervention interviews among all residents that were able to respond (N = 39), and by means of observations. Results showed that most respondents evaluated the refurbishment of both spaces positively on residential quality, aesthetic quality, and possibility for controlled interaction. In addition, residents’ subjective well-being increased significantly. Subjective well-being appeared to be quite strongly related to the 3 evaluative aspects. Results suggest that the physical changes in care homes can help improve residents’ subjective well-being.  相似文献   
57.
卢颖  黄炎  姜学鹏 《火灾科学》2021,30(4):185-191
为预防养老院火灾事故,结合事故树法(FTA)和贝叶斯网络法(BN),建立了一套养老院火灾风险定量评估模型。首先,采用事故树法建立潜在的养老院火灾事故场景;其次,考虑到养老院火灾事故场景中不确定因素的影响,将事故树模型转化为贝叶斯网络模型,并结合有人员伤亡的养老院火灾事故发生发展实际优化模型;最后,以某市养老院为例,结合调研、文献及统计数据确定先验概率及条件概率,并用GENIE 2.0软件实现贝叶斯图形化,分析验证该模型逻辑可行性。结果表明:通过该模型和方法,不仅可以预测养老院火灾事故中各场景发生发展概率,还能对各风险因素敏感度和最大致因链进行分析,提高了风险因素辨识和评价的准确性,可以为养老院火灾风险分析和防控提供参考。  相似文献   
58.
Abstract:  Although species with large area requirements are sometimes used as umbrella species, their general utility as conservation tools is uncertain. We surveyed the species diversity of birds, butterflies, carabids, and forest-floor plants in forest sites across an area (1600 km2) in which we delineated large breeding home ranges of Northern Goshawk ( Accipiter gentilis ). We tested whether protection of the home ranges could serve as an effective umbrella to protect sympatric species of the four taxa. We also used an empirical habitat model of occupancy of home range to examine mechanisms by which the Northern Goshawk acts as an umbrella species. Among species richness, abundance, and species composition of the four taxa, only abundance and species composition of birds differed between sites located inside and outside home ranges, which was due to greater abundance of bird species that were prey of Northern Goshawks inside the home ranges. Thus, although home range indicated areas with high abundance of certain bird prey species, it was not effective as an indicator of the species diversity of all four taxa. We also did not find any difference in species richness, abundance, and species composition between sites predicted as occupied and unoccupied using the habitat model. In contrast, when we selected sites on the basis of each habitat variable in the model, habitat variables that selected sites either in agricultural or forested landscapes encompassed sites with high species richness or particular species composition. This result suggests that the low performance of the Northern Goshawk as an umbrella species is due to this species' preference for habitat in both agricultural and forested landscapes. Species that can adjust to changes in habitat conditions may not act as effective umbrella species despite having large home ranges.  相似文献   
59.
INTRODUCTION: While smoke alarm installation programs can help prevent residential fire injuries, the costs of running these programs are not well understood. METHOD: We conducted a retrospective cost analysis of a smoke alarm installation program in 12 funded communities across four states. Costs included financial and economic resources needed for training, canvassing, installing, and following-up, within four cost categories: (a) personnel, (b) transportation, (c) facility, and (d) supplies. RESULTS: Local cost per completed home visit averaged 214.54 dollars, with an average local cost per alarm installed of 115.02 dollars. Combined state and local cost per alarm installed across all four states averaged 132.15 dollars. For every 1% increase in alarm installation, costs per alarm decrease by 1.32 dollars. CONCLUSIONS: As more smoke alarms are installed, the average installation cost per alarm decreases. By demonstrating effective economies of scale, this study suggests that smoke alarm programs can be implemented efficiently and receive positive economic returns on investment.  相似文献   
60.
家用电器的更新换代使得废旧家电的资源化利用问题日益突出,不合理处置和回收会给环境造成极大污染。因此,广泛开展废旧电器回收利用方面的研究,使这些宝贵的二次资源得到科学合理的资源化和无害化处置,对保证人类所需生产和生活资源的永续利用,促进人类的可持续发展具有十分重要的意义。介绍了中国废旧家电年废弃量及回收利用价值,总结了处理废旧家电的基本技术特点及中国处置技术方面存在的问题。在此基础上,对中国废旧家电回收处理工艺提出建议和对策。  相似文献   
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