Results 41 to 50 of about 1,872 (166)

Study of Sound Characteristics of Rain Noise at Sea [PDF]

open access: yes, 2012
海上降雨引起的噪声信号(简称降雨噪声)是海洋环境噪声背景场的一个重要干扰源,会极大地降低声呐的检测能力,影响水声通信的应用频段和降低水声设备的性能。考虑未来的海战极可能是在恶劣天气(往往伴随疾风暴雨)下进行,充分掌握降雨噪声的特性,不仅在军事上有利于检测海洋环境噪声背景中的干扰源,提升水声设备的作战效能,而且在民用上可拓展应用声学方法监测海上降雨的技术。近几十年来,美国等发达国家为了解释降雨噪声的产生机制,对自然界的降雨噪声开展了大量观测。前期的研究成果表明 ...
刘贞文
core  

Influence of interactive effects on long‐term population trajectories in multispecies reintroductions

open access: yesConservation Biology, Volume 38, Issue 3, June 2024.
Abstract Reintroduced populations are typically considered to progress through establishment, growth, and regulatory phases. However, most reintroduction programs do not monitor intensively enough to test this conceptual model. We studied population indices derived from track activity of 4 threatened species (greater bilby [Macrotis lagotis], burrowing
Katherine E. Moseby   +3 more
wiley   +1 more source

不同雨型下紫色土区坡耕地产流产沙特征

open access: yesShuitu Baochi Xuebao, 2017
利用遂宁水土保持试验站5个径流小区1984—2015年次降雨和径流输沙数据,基于降雨过程定量划分出4种雨型,分析了雨型对不同坡度坡耕地产流产沙的作用。结果表明:径流深与各时段最大雨强均呈极显著相关(p<0.01),随着坡度的增加,最大相关系数所对应的雨强时段越短;冲刷量均与I平均呈极显著相关,且相关系数最大。径流深、冲刷量与雨强拟合关系均为幂函数,分别为“凸型”和“凹型”增函数,且拟合度区间分别为[0.79,0.88]和[0.90,0.97],说明冲刷量和雨强的关系更密切 ...
马, 陈, 单志杰, 郎登潇, 廖
doaj  

Analysis on factors controlling shallow failures of the cut slopes and its prevention by bio-engineering measures: A case study of the cut slopes along the highway from Shuangcheng to Dajiali [PDF]

open access: yes
Understanding the primary and secondary relations of influencing factors is crucial for predicting deformation and controlling collapse in cutting slopes. Using a cutting slope along the Shuangcheng to Dalijia expressway in Gansu Province as the research
Changgen YAN   +4 more
core   +1 more source

Layered gravel soil slope stability of a waste dump considering long-term hard rain [PDF]

open access: yes, 2016
In order to examine the effect of long-term hard rain on the layered gravel soil slope stability of a waste dump, the for-mula derivation relating natural water content, natural unit weight and natural volumetric water content was conducted to help to ...
LUO Cheng-yan   +3 more
core   +1 more source

Ecology, status, and distribution of Temminck's pangolin (Smutsia temminckii) in Hwange National Park 万基国家公园南非地穿山甲 (Smutsia temminckii) 的生态、现状和分布

open access: yesWildlife Letters, Volume 2, Issue 1, Page 17-22, March 2024.
Temminck's pangolin faces conservation threats, mainly habitat fragmentation, poaching, and trafficking. The study assessed the ecology, status, and distribution of Temminck's pangolin in Hwange National Park and directly sighted seven specimens. Biotic and abiotic factors influence pangolin distribution inside and outside protected areas.
Kelly Sabashau   +4 more
wiley   +1 more source

喀斯特裸露坡耕地径流养分流失试验研究

open access: yesShuitu Baochi Xuebao, 2016
为揭示雨强对喀斯特坡耕地养分流失的影响,运用可调坡度、地下孔(裂)隙度试验钢槽装填土石模拟喀斯特裸露坡耕地,采用人工模拟降雨的方法研究不同雨强下喀斯特裸坡径流养分流失特征。结果表明:(1)雨强为15,30 mm/h时地表不产流,雨强50 mm/h时地表有产流;试验雨强下地下孔(裂)隙均有径流产生。(2)地表径流中全氮和全钾流失量均随雨强增大而增大,全磷流失量则先增大后减小;地下径流中全氮流失量随雨强增大呈先增大后减小趋势,全钾流失量与雨强正相关,全磷流失量与雨强关系不明显。(3)雨强为30,50 mm ...
靳 丽   +4 more
doaj  

Exploring thematic influences on theme park visitors' satisfaction: An empirical study on Disneyland China

open access: yesJournal of Consumer Behaviour, Volume 23, Issue 1, Page 90-106, January 2024.
Abstract This study aims to explore thematic influences on theme park visitors' satisfaction through user‐generated data. To this end, we first used an unsupervised machine learning method, structural topic modeling, and analyzed 112,000 reviews post by visitors to Shanghai Disney Resort from June 16, 2016 to March 4, 2022.
Shizhen Bai   +8 more
wiley   +1 more source

间歇降雨对红壤坡面土壤侵蚀特征的影响

open access: yesShuitu Baochi Xuebao, 2021
自然条件下降雨多以间歇形式出现,而坡面土壤侵蚀又是一个渐变发育的复杂过程。通过3个雨强(60,90,120 mm/h)、5个坡度(5°,10°,15°,20°,25°)下的15场室内模拟降雨,研究一、二次降雨条件下不同雨强、坡度及降雨量对红壤坡面径流和侵蚀过程的影响,探讨间歇降雨条件下坡面侵蚀发育过程及其主要影响因素的变化。结果表明:(1)二次降雨的产流时间相比一次降雨均提前,一次降雨径流总量受到雨强、坡度和降雨量的共同影响,15°坡度是径流总量变化的一个转折点,二次降雨时降雨量的作用减弱 ...
李霞   +6 more
doaj  

Impacts of storm event on DOM composition and flux in two Jiulong Tributaries with different watershed features [PDF]

open access: yes, 2016
通过调查2014年7月"麦德姆"台风影响期间福建九龙江北溪(流域以林地为主)和西溪(农业流域和城市背景)下游定点站DOM的时间序列,测定样品的DOC含量及其吸收光谱和三维荧光光谱,以评估不同流域背景对河流DOM动力学降雨响应的差异性,并为流域-河口系统的一体化管理提供重要参考。降雨期间,两条河流DOC浓度、吸收系数aCDOM(350)以及总荧光强度均随径流量升高而增大,并在水位下降期持续增加,且西溪增加量明显高于北溪,说明受人类活动扰动大的流域河流有机质对暴雨事件的响应更为灵敏 ...
徐静   +5 more
core  

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