Conflict of interest in research on anthropogenic noise and marine mammals: Does funding bias conclusions?     

Lucie Wade  Hal Whitehead  Linda Weilgart   《Marine Policy》2010,34(2):320-327

The U.S. Navy, whose sonars kill marine mammals, provides approximately 50% of the funds for marine mammal research worldwide. We examined six reviews of research on the effects of anthropogenic sound on marine mammals, as well as the primary papers cited in the reviews. These reviews cite references showing noise has no effect on marine mammals at an increasing frequency as their funding moves from a conservation organization to independent to partial U.S. military sources. Primary papers are 2.3 times more likely to be cited in the reviews as concluding no effect of noise if the research was militarily-funded than if not. Thus, conflict of interest may have led to a misrepresentation of the effects of noise on marine mammals in both the primary and secondary literature, and thus misinform public policy decisions.  相似文献   

NI4472在海洋噪声和传播损失测量中的应用   总被引：1，自引：0，他引：1  

崔华义  周长兴 《海洋技术学报》2003,22(3):74-75

利用NI公司的高性能数据采集板NI4472来进一步改善海洋噪声和传播损失的测量情况。  相似文献   

Recreational boat noise level evaluation     

Professor J. M. Vasconcellos  Professor R. G. Latorre   《Ocean Engineering》2001,28(9)

Recreational boats are constantly undergoing modifications and improvements in design, construction materials, and equipment. The boat builder mission is supply customers with a product with better quality, safety and onboard comfort. Onboard comfort should be evaluated along several points. Seakeeping is especially critical on long trips or operations in regions where harsh sea conditions occur. Over the years much attention has been given to boat behavior underway at sea. Recently onboard noise level has become a significant element of comfort and navigation safety. With high onboard noise a boater is unable to detect other boat whistles, horns and calls for help. This becomes a critical problem when sailing in fog and at night. Maintaining the internal noise level within limits is important. In order to address this noise problem, the paper presents a review of existing guidelines and the authors' proposal for Boat Noise Evaluation (BNE) procedure for recreational powerboats. This procedure has been used in a number of boat trials. The use of this procedure is discussed along with representative boat noise level results and a comparison with the acceptable values for passenger comfort and safety.  相似文献   

地震勘探基于波场分离的逆时偏移去噪方法     

张书杰  ;薛霆虓 《云南地质》2014,(2):250-253

基于双程波动方程的逆时偏移（RTM）具有原理简单、无倾角限制、可以适用于速度任意变化的模型,并具有对各类波正确成像等优点,是当今最好的偏移方法之一.本文阐述了逆时偏移存在的缺陷并分析了低频噪声的产生机制,重点探讨了使用波场分离的逆时偏移去噪方法,并通过模型的试算证明了该方法的有效性.  相似文献   

Human and policy dimensions of soundscape ecology     

《Global Environmental Change》2014

Soundscape ecology is an emergent and potentially transformative scientific discipline. However, the majority of research within the field has been conducted by natural scientists focused on quantifying the characteristics and dynamics of soundscapes and examining their effect on non-human biota. A more holistic approach to the science and management of soundscapes requires full integration with the social and policy sciences. To facilitate the development of this integration, we propose an integrative human and policy dimensions of soundscape ecology framework that conceptualizes the complex and dynamic relationships between humans and their acoustic environments. The framework is grounded in four distinct disciplines – health, psychology, economics and anthropology – that have used different methodologies and metrics to focus on certain aspects of human–soundscape interactions. We provide a review of previous empirical research within each of these fields. Along the way, we identify unexplored avenues of discipline-specific research that can further the field of soundscape ecology. The human and policy dimensions of soundscape ecology framework provide the logic and structure upon which an interdisciplinary body of scholarship can be built in the future. We conclude by utilizing our review and integrative framework to propose specific focused soundscape policy and management recommendations. We argue the anthropogenic dominance of soundscapes can be mitigated through more proactive, integrative and holistic soundscape policies and management practices.  相似文献   

叠前逆时深度偏移低频噪声压制策略研究   总被引：8，自引：5，他引：3       下载免费PDF全文

杜启振  朱钇同  张明强  公绪飞 《地球物理学报》2013,56(7):2391-2401

低波数噪音严重影响了逆时偏移的成像质量,选择合适的低波数噪音压制方法是进行逆时偏移时必然涉及到的一个重要方面.本文首先详细分析了逆时偏移中低波数噪音产生的本质原因,然后根据噪音的产生机制对目前各类低波数噪音压制方法进行了分析和归类:第一类低波数噪音压制策略的核心是在构建波场中避免发生背向反射;第二类低波数噪音压制策略的核心是进行选择性成像.最后通过对压噪方法进行合理的选择和搭配,构建了在不同实现条件和成像需求情况下逆时偏移去噪方法的最佳抉择策略.结合数值算例对几种压噪方案进行了测试和比较,实例表明了对噪音压制方法进行合理的搭配可以获得高信噪比逆时偏移成像结果.  相似文献   

基于双通道参考技术的磁共振地下水探测电磁噪声分布规律研究          下载免费PDF全文

林婷婷  于思佳  么晓康  韦萌  张扬 《地球物理学报》2021,64(1):355-362

磁共振地下水探测(MRS)技术能直接测量水中氢质子的拉莫尔进动,可表征地下水含水量和介质孔隙度等信息,因而获得了广泛应用.然而,MRS信号微弱,实际探测中电磁噪声强度大,若噪声未被有效去除,会导致后续水文参数解释不准确,采用“8”字形线圈或运用带参考线圈的噪声抵消等方法可抑制噪声干扰,但这些方法消噪效果的好坏取决于电磁噪声的空间分布.另外,在强噪声或多噪声源环境下应用MRS方法,选择恰当的探测位置对提高探测效率以及增加探测结果的有效性具有重要意义.因此,本文使用双通道噪声采集装置在实验前记录环境中的电磁噪声,通过双通道参考技术推导同一时刻不同测点的噪声强度,再得到测区电磁噪声分布结果,该噪声分布情况对MRS方法探测方式的选取具有指导性的作用.同时,可根据噪声分布情况为探测线圈选择最佳测点以避开噪声强度大的区域,进而提高采集信号的信噪比.最后,通过采集室外环境下的电磁噪声,验证本文提出的基于双通道参考技术的电磁噪声分布规律研究方法的有效性,为可靠高效地开展磁共振地下水探测提供了新的技术手段.  相似文献   

伪码捕获过程性能分析及计算机模拟     

吴士达  陈颖  张瑞桃 《成都信息工程学院学报》1996,(Z1)

根据伪码捕获系统的工作原理，建立了描述伪码捕获过程的数学模型。在此基础上详细分析了捕获性能并导出了完成捕获过程所需的步数，提出了缩短捕获时间的办法。本文还用计算机对捕获过程进行了模拟，模拟测试结果和理论分析结果相当吻合。  相似文献   

微波混频器噪声特性研究     

李庆 《成都信息工程学院学报》1989,(4)

本文讨论了在小信号下混频器内部参数Rs,Cj及混频器所有可能端口(ω_m=ω_o+ω_p) 对总的混频器噪声系数的影响、推导出了噪声系数公式、得出了镜像匹配及抑制下的噪声表达式。  相似文献   

图象中噪声的统计特性和模型     

曾文庆  杨为民  张柏荣 《天文研究与技术》1993,(2)

本文描述了图象中的噪声特性,着重讨论了与信号有关的噪声的模型及其统计特性,特别是颗粒噪粒噪声和光电散粒噪声。指出磁带记录噪声是一种与信号有关的噪声。在Naderi和Sawchuk图象中噪声模型的基础上,针对CCD摄象机的图象数字化,提出了底片数字化图象的模糊和退化模型。  相似文献