Results 41 to 50 of about 12,599 (118)

Engaging youth in biodiversity education through visual narrative

open access: yesConservation Biology, Volume 38, Issue 6, December 2024.
Abstract Engaging youth in early and sustained conservation education has important implications for promoting positive attitudes and behaviors in those who will become the future of conservation and management. Toward this goal, visual narratives (comic books, graphic novels) are an increasingly popular method used by conservation scientists to ...
Kyra Ricci   +3 more
wiley   +1 more source

Community perceptions of invasive species and environmental management in a US island territory

open access: yesConservation Biology, Volume 38, Issue 6, December 2024.
Abstract Environmental managers struggle with communicating accurate and relevant information and with gaining trust from the communities they serve, problems that are especially pronounced in minority and colonized communities. An important step in developing successful management strategies is partnering directly with the communities involved, but ...
Ann Marie Gawel   +2 more
wiley   +1 more source

深井型直流接地极散流机理研究

open access: yesDianci bileiqi, 2020
准确计算直流接地装置的散流性能及接地特性是优化设计直流接地极的基础。提出了基于恒定电场理论的直流接地装置性能有限元数值计算模型,针对求解区域和接地导体截面尺寸的差异导致的剖分困难、计算量大的问题,引入"薄壳"理论,在保证计算精度的前提下大大减小了计算量;通过与文献数据对比,验证了该方法的有效性。建立典型结构的深井型接地极模型,计算深井接地极散流过程产生的地中电流密度、电场强度、接地电阻和最大跨步电压等参数;分析电流注入点个数、接地极导体长度、接地极埋深、导体并联根数以及土壤电阻率等因素对接地性能的影响 ...
李景丽, 冯鹏, 栗超超
doaj  

The soft channels of policy diffusion: Insights from local climate change adaptation policy

open access: yesPolicy Studies Journal, Volume 52, Issue 4, Page 881-906, November 2024.
Abstract Diffusion has become both an important concept for studying policy spread and a popular governance approach, particularly where direct coercion is unavailable or undesirable. However, the prevailing mechanism‐centered concept is difficult to measure and poorly captures the governance potential of policy diffusion. To address these issues, this
Kai Schulze
wiley   +1 more source

城镇污水处理厂碳排放及碳中和路径分析

open access: yesJingshui jishu
【目的】为厘清污水处理厂的碳排放来源、特征和排放强度,提出可行的污水处理厂碳中和实施路径,本文以4座典型污水处理厂(涵盖地上/地下式、不同污水、污泥处理工艺)为例,系统分析污水处理厂的碳中和路径。【方法】本文基于政府间气候变化专门委员会(IPCC)计算方法,选取适合我国国情的排放因子,根据进出水水质、处理负荷、电耗、药耗等数据,系统核算了各污水厂碳排放强度及其影响因素,评估了不同碳汇措施的碳汇及其碳中和潜力。【结果】4座污水厂的碳排放强度为0.510~1.086 kg CO 2 ...
ZHU Jie
doaj   +1 more source

Cytological evaluation, culture and genomics to evaluate the microbiome in healthy rabbit external ear canals

open access: yesVeterinary Dermatology, Volume 35, Issue 5, Page 479-491, October 2024.
Background – Lop‐eared rabbits may be predisposed to otitis externa (OE) as a consequence of their ear conformation. Although otoscopy, otic cytological evaluation, and culture are valuable tools in dogs and cats, published data on rabbits remain lacking. Hypothesis/Objectives – This study aimed to assess the utility of otoscopy and cytological results
Nikoleta Makri   +8 more
wiley   +1 more source

直流配电系统闪变检测方法研究

open access: yesGaoya dianqi
与交流配电系统一样,表征直流配电系统特征指标的直流电压、直流电流也在时刻变化着且其变化幅度、变化频度均具有很强的随机性,导致接入电网的照明类负载灯光照度的随机变化,引起感受体—人对照度变化的视感即常说的闪变。相比于交流配电系统已有公认的、标准化的闪变测量方法,直流配电系统的闪变测量方法目前还处于研究探讨之中。文中基于直流配电系统的特点,在分析传统交流配电系统平方解调闪变测量方法的基础上提出了一种适用于直流配电系统的去平方解调闪变测量方法;仿真分析表明:该方法准确度高 ...
苏灿   +5 more
doaj  

受弯的冷弯卷边槽钢畸变屈曲强度和其相关屈曲承载力

open access: yesJianzhu Gangjiegou Jinzhan, 2009
受弯的冷弯薄壁卷边槽钢基本上有板件局部屈曲,截面畸变屈曲和构件弯扭屈曲三种屈曲模式,随后有它们之间的相关屈曲。由于畸变屈曲模式对缺陷的敏感度高,因此其屈曲后强度提高的幅度远低于局部屈曲模式。但是与局部屈曲模式相比,畸变屈曲模式抵抗破坏的能力却很强。可以用有限单元法计算受弯卷边槽钢截面的畸变屈曲强度。本文介绍了澳大利亚-新西兰标准AS/NZS4600-2005,用手算法计算受弯卷边槽钢截面的弹性畸变屈曲应力,並用直接强度法计算其相关的屈曲承载力。
陈骥
doaj  

自锁式单向高强螺栓预拉力与扭矩关系的试验研究

open access: yesJianzhu Gangjiegou Jinzhan, 2022
单向螺栓是一种仅在一侧操作便能完成安装的螺栓,因此在闭口截面构件中的连接具有优势。预拉力是保障高强度螺栓连接抗拉刚度的重要参数,但单向螺栓的预拉力和扭矩之间的关系尚不明确。分析了自锁式单向高强螺栓在安装过程与拉伸过程中的受力情况,给出了单向螺栓预拉力的计算方法。对于三种直径、两种强度的标准化自锁式单向螺栓和非标准化自锁式单向螺栓进行了拉伸试验,并基于拉伸试验的荷载-位移曲线,得到了不同型号自锁式单向螺栓在不同拉伸试验中的钢板分离荷载,并根据公式计算得到了单向螺栓在不同安装扭矩下的预拉力值 ...
蒋蕴涵, 李国强, 陈琛, 侯兆新
doaj  

特高压换流阀用水冷散热器热阻测试方法研究

open access: yesGaoya dianqi, 2017
晶闸管换流阀用水冷散热器是换流阀的关键器件,笔者在研制±800 k V/6 250 A特高压直流工程换流阀样机时,为了对水冷散热器性能评价的重要指标—热阻的测试进行更加准确的测量,在查阅资料和总结现有方法的基础上提出了一种多点布置和通过进出水温度计算耗散功率的简单可行、操作性强、相对更为直接的测试方法,此方法较为适合工程应用。通过仿真和试验验证了所用方法正确,可操作性强。
马元社   +6 more
doaj  

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