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排序方式: 共有112条查询结果,搜索用时 31 毫秒
51.
采用多种调查技术与方法 ,对尚勇自然保护区周边地区社会经济现状进行分析。该区存在群众文化素质偏低 ,医疗卫生状况较差 ,农业生产方式落后 ,保护区管理缺乏群众参与 ,保护区管理部门与周边乡村关系不够融洽等问题。针对这些问题 ,相应地提出了社区社会经济可持续发展的一系列对策  相似文献   
52.
The rapid rise of citizen science, with lay people forming often extensive biodiversity sensor networks, is seen as a solution to the mismatch between data demand and supply while simultaneously engaging citizens with environmental topics. However, citizen science recording schemes require careful consideration of how to motivate, train, and retain volunteers. We evaluated a novel computing science framework that allowed for the automated generation of feedback to citizen scientists using natural language generation (NLG) technology. We worked with a photo‐based citizen science program in which users also volunteer species identification aided by an online key. Feedback is provided after photo (and identification) submission and is aimed to improve volunteer species identification skills and to enhance volunteer experience and retention. To assess the utility of NLG feedback, we conducted two experiments with novices to assess short‐term (single session) and longer‐term (5 sessions in 2 months) learning, respectively. Participants identified a specimen in a series of photos. One group received only the correct answer after each identification, and the other group received the correct answer and NLG feedback explaining reasons for misidentification and highlighting key features that facilitate correct identification. We then developed an identification training tool with NLG feedback as part of the citizen science program BeeWatch and analyzed learning by users. Finally, we implemented NLG feedback in the live program and evaluated this by randomly allocating all BeeWatch users to treatment groups that received different types of feedback upon identification submission. After 6 months separate surveys were sent out to assess whether views on the citizen science program and its feedback differed among the groups. Identification accuracy and retention of novices were higher for those who received automated feedback than for those who received only confirmation of the correct identification without explanation. The value of NLG feedback in the live program, captured through questionnaires and evaluation of the online photo‐based training tool, likewise showed that the automated generation of informative feedback fostered learning and volunteer engagement and thus paves the way for productive and long‐lived citizen science projects.  相似文献   
53.
Abstract:  Without robust and unbiased systems for monitoring, changes in natural systems will remain enigmatic for policy makers, leaving them without a clear idea of the consequences of any environmental policies they might adopt. Generally, biodiversity-monitoring activities are not integrated or evaluated across any large geographic region. The EuMon project conducted the first large-scale evaluation of monitoring practices in Europe through an on-line questionnaire and is reporting on the results of this survey. In September 2007 the EuMon project had documented 395 monitoring schemes for species, which represents a total annual cost of about €4 million, involving more than 46,000 persons devoting over 148,000 person-days/year to biodiversity-monitoring activities. Here we focused on the analysis of variations of monitoring practices across a set of taxonomic groups (birds, amphibians and reptiles, mammals, butterflies, plants, and other insects) and across 5 European countries (France, Germany, Hungary, Lithuania, and Poland). Our results suggest that the overall sampling effort of a scheme is linked with the proportion of volunteers involved in that scheme. Because precision is a function of the number of monitored sites and the number of sites is maximized by volunteer involvement, our results do not support the common belief that volunteer-based schemes are too noisy to be informative. Just the opposite, we believe volunteer-based schemes provide relatively reliable data, with state-of-the-art survey designs or data-analysis methods, and consequently can yield unbiased results. Quality of data collected by volunteers is more likely determined by survey design, analytical methodology, and communication skills within the schemes rather than by volunteer involvement per se.  相似文献   
54.
This paper critically examines how public policy makers limit policy and other institutional design choices by a failure to appreciate (i) how situations may be characterised or framed; (ii) how practices that generate neologisms (invented terms or concepts) or reify (make into a thing) abstract concepts can displace understandings, and (iii) the epistemological bases of governance mechanism choices. An inquiry into the coining of the neologisms ‘wicked’ and ‘tame’ problems is reported and the implications for research and policy practice explored. As practices, neologising, reifying, categorising and typologising have unintended consequences – they remove us from the primary experiences and underlying emotions that provided the motivation for formulating these concepts in the first place. The failure to institutionalise the understandings and experiences that sit behind the invention of the terms ‘wicked’ and ‘tame’ problems (or similar framing choices such as ‘problematique’, ‘messes’, ‘lowland real-life swamps’, ‘resource dilemmas’ or ‘complex adaptive systems’) present systemic constraints to institutionalising social learning as an alternative yet complementary governance mechanism within an overall systemic and adaptive governance framework. Ultimately situations usefully framed as ‘wicked’,’ such as water managing and climate change are problems of relationship – of human beings with the biosphere. Re-framings, such as institutions as social technologies and other research and praxis traditions concerned with the breakdown of relationships may offer ways forward in the purposeful designing and crafting of more effective institutions.  相似文献   
55.
Abstract

In the past, many so-called management concepts were not very successful because of their fragmented approach. This is also true for topics like safety and quality. Here, technical aspects often predominated while disregarding the equally important need for a change of attitude. On the other hand, awareness was created by timely limited programmes.

The paper deals with integrating quality and safety in holistic (management) concepts, which are described first before being discussed in detail.  相似文献   
56.
高职院校大学生参加社区志愿活动具有重要的意义,有助于提高学生综合素质、增强学生社会责任感,但是其存在缺乏科学指导、缺乏持续性和学生及社区居民对其认识不足等问题。为了使高职院校学生顺利开展社区志愿服务活动,应该加强引导和管理,提高学生志愿服务意识,政府应该出台激励社区志愿活动政策,切实增强高职院校学生参加社区志愿活动的实效性。  相似文献   
57.
随着经济全球化、城市化进程的加剧,城市生态的规划建设对社会经济发展起着至关重要的作用。从可持续发展视域探讨当前城市规划建设中存在的由规划滞后、规划重复、规划片面、执法不严等造成的城市规划环境污染、资源浪费和生态破坏的问题,提出构建城市生态规划的现实必然性和基本原则,从强化机制、转变观念、以人为本、健全法制、合理规划等角度探讨可持续发展视阈下城市生态规划的途径。  相似文献   
58.
北京地区喀斯特景观是中国温带喀斯特发育最为壮观的典型地区之一.对北京地区典型喀斯特(石花洞、银狐洞、云水洞、京东大溶洞)岩溶洞穴特征进行了分析,并将其与全球涉及岩溶洞穴的世界自然遗产地进行对比,以此探讨北京地区喀斯特洞穴的自然遗产价值,指出北京地区喀斯特景观存在的问题,提出相关的保护对策,以推进世界遗产的可持续发展.  相似文献   
59.
快速工业化区域是工业化快速发展、工业化水平迅速提升、经济社会结构急剧变化的新兴地域类型。普遍存在着建设用地总量急剧扩张、空间无序分散、城乡缺乏统筹等问题。本文从佛山市南海区典型案例入手,运用新制度经济学原理。归纳和解析了快速工业化区域城乡建设用地的主要问题,认为双二元管理体制、农村土地产权不完善、城乡土地市场发育不平衡和部门规划不协调等是建设用地发展的主要体制性障碍因素,并从管理、产权、市场、规划等方面系统提出相应的制度优化对策。  相似文献   
60.
Abstract

Objective: The introduction of integrated safety technologies in new car models calls for an improved understanding of the human occupant response in precrash situations. The aim of this article is to extensively study occupant muscle activation in vehicle maneuvers potentially occurring in precrash situations with different seat belt configurations.

Methods: Front seat male passengers wearing a 3-point seat belt with either standard or pre-pretensioning functionality were exposed to multiple autonomously carried out lane change and lane change with braking maneuvers while traveling at 73?km/h. This article focuses on muscle activation data (surface electromyography [EMG] normalized using maximum voluntary contraction [MVC] data) obtained from 38 muscles in the neck, upper extremities, the torso, and lower extremities. The raw EMG data were filtered, rectified, and smoothed. All muscle activations were presented in corridors of mean?±?one standard deviation. Separate Wilcoxon signed ranks tests were performed on volunteers’ muscle activation onset and amplitude considering 2 paired samples with the belt configuration as an independent factor.

Results: In normal driving conditions prior to any of the evasive maneuvers, activity levels were low (<2% MVC) in all muscles except for the lumbar extensors (3–5.5% MVC). During the lane change maneuver, selective muscles were activated and these activations restricted the sideway motions due to inertial loading. Averaged muscle activity, predominantly in the neck, lumbar extensor, and abdominal muscles, increased up to 24% MVC soon after the vehicle accelerated in lateral direction for all volunteers. Differences in activation time and amplitude between muscles in the right and left sides of the body were observed relative to the vehicle’s lateral motion. For specific muscles, lane changes with the pre-pretensioner belt were associated with earlier muscle activation onsets and significantly smaller activation amplitudes than for the standard belt (P?<?.05).

Conclusions: Applying a pre-pretensioner belt affected muscle activations; that is, amplitude and onset time. The present muscle activation data complement the results in a preceding publication, the volunteers’ kinematics and the boundary conditions from the same data set. An effect of belt configuration was also seen on previously published volunteers’ kinematics with lower lateral and forward displacements for head and upper torso using the pre-pretensioner belt versus the standard belt. The data provided in this article can be used for validation and further improvement of active human body models with active musculature in both sagittal and lateral loading scenarios intended for simulation of some evasive maneuvers that potentially occur prior to a crash.  相似文献   
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