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The rainforests of Southeast Asia have a high diversity of animals, many of which eat fruit and disperse the seeds of forest plants. Several large‐bodied species occur in these forests; these animals are predicted to have especially important seed dispersal roles but are also among the species most threatened by defaunation.
Aurélie Albert‐Daviaud +8 more
wiley +1 more source
Adapting a Coparenting‐Focused Prevention Program for Latinx Adolescent Parents in a School Context
The current study utilized a three‐step cultural adaptation process to adapt a universal‐coparenting program for Latinx adolescent parents in a school‐based setting. First, focus groups were conducted with adolescent parents (n = 13; 100% Latinx; 69% female), their parents (n = 17; 94% Latinx; 82% female), and school staff (n = 7; 71% White; 100 ...
Norma J. Perez‐Brena +3 more
wiley +1 more source
In the BEF‐China experiment, metabolomics samples were collected from four different species and three organs (a). The metabolomes are species and organ specific (b), and the metabolome specificity is attributed to different chemical classes (c). Tree species diversity affects the metabolome composition (d), but more controlled interaction experiments ...
Alexander Weinhold +7 more
wiley +1 more source
水路及均压电极布置方式对MMC换流阀阀端间交直流耐压试验的影响研究
MMC换流阀阀端间交直流耐压试验时,换流器闭锁,电容电压控制算法未投入使用,因此,子模块的均压特性受系统阻容网络的影响。根据试验录波结果,阀塔层间子模块电压分布规律为顶层和底层高,中间层低,子模块电压先发散,后趋于平衡。经过分析得到水路及均压电极布置方式对系统阻容网络有很大的影响,是试验过程中造成层间子模块不均压的主要因素。通过搭建MMC换流阀阀端间交直流耐压试验详细仿真模型,仿真得到层间子模块电压分布规律与试验基本一致,10 s试验最大不均压度为3.9%,3 h试验最大不均压度8.9 ...
梁家豪 +7 more
doaj
目前模块化多电平换流器已经成为全球柔性直流输电工程建设的首选,并在直流配电技术领域得到了进一步的广泛应用。文中针对模块化多电平换流器在应用过程中需要面临的子模块检测工作量大、效果差、功能覆盖不全等问题,对其检测技术进行了研究。首先结合相关技术标准和实际生产需求分析了检测现状,然后基于目前两种主流检测方法的技术原理和特点提出了一种全新的模块化多电平换流器子模块检测方法,最后通过仿真验证了该方法的合理性和可行性,能够实现多个子模块的一次性自动检测,覆盖了子模块中除晶闸管外的所有功率组件 ...
杨贵军 +5 more
doaj
基于半桥结构的模块化多电平变流器(modular multilevel converter,MMC)因其具有功率大、电压等级高等特点,在柔性直流输电系统中被广泛应用。与载波移相调制(carrier phase shift modulation,CPS-PWM)相比,最近电平逼近调制(nearest level modulation,NLM)具有控制简单,开关频率低的显著优势。但在输出电平较少时,NLM调制输出电流谐波畸变率较大。因此,文中在传统MMC的每个桥臂中串入1个全桥子模块 ...
荣飞, 孙宗卿, 徐爽, 潘烙
doaj
Design and Implementation of Library Management System for NanCang Vocational College [PDF]
在这个计算机应用技术高速发展时代里,随着图书馆规模的不断扩大、图书数量的不断增加,读者需求也在不断地增加。在日常管理中,一个现代化的图书馆在日常管理中总是要面对大量的读者、图书以及借书、还书等活动。而传统的图书管理方法既浪费人力、物力、财力,又容易导致各种错误的产生。基于这些问题,拟建立一个图书管理系统,使图书管理工作规范化,程序化,系统化,避免图书管理的随意性,提高信息处理的速度和准确性,能够及时、准确、有效的查询和修改图书情况。 本文将以南昌职业学院图书馆目前图书的管理方式作为研究对象 ...
王海伦
core
Qilianshan National Park covers approximately 40% of core snow leopard habitat patches and 50% of movement corridors between patches. Including more of these important areas within the park boundaries should be considered, as the Qilianshan National Park sits at a pivotal juncture between critical snow leopard habitat in China and Mongolia, and may ...
Aliana Norris +6 more
wiley +1 more source
在多端柔性直流电网中,直流故障快速隔离和清除能力是系统可靠安全运行的保障。直流故障清除能力是制约基于半桥模块MMC发展的关键问题。文中提出了一种新型二极管箝位双子模块拓扑结构,在两个单子模块串联的基础上,增加了一个IGBT和一个二极管,利用子模块电容电压迫使导通的二极管反向截止,从而有效抑制MMC的不控整流效应,快速切断故障电流通路,具备直流故障自消除能力,具有很好的经济性和应用价值。
孙银山, 杨晓平, 任军辉
doaj
Design and Implementation of Customer Management System of Clothing Chain Business Management System [PDF]
因国家产业结构性调整以及客户群体购买方式的转变,各传统服装品牌的竞争已趋向于拼价格,而轻视服务。为了有效引导和规范各部门步入良性竞争轨道,常州某服饰企业决定舍弃现有用友T6系统,重新定制开发一套自上而下的产销服务一体的业务管理系统。 随着公司经营模式转变、管理制度的变革和信息技术的迅猛发展,使得现有用友T6系统无法满足目前常州某服饰连锁的业务发展需要,也无法与其他行业业务管理系统实现对接,业务管理系统已经成为公司创新发展的瓶颈。现有用友T6系统只涉及配送、零售、简单核算模块,生产、服务、人事等模块未涉及。
吴春晖
core

