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Antenna design for a massive multiple input environmental sensor network 被引量:2
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作者 J. Craig Prather Michael Bolt +2 位作者 Haley Harrell John Manobianco Mark L. Adams 《Digital Communications and Networks》 SCIE 2016年第4期256-259,共4页
This article describes the design and simulation of a pair of antennas on a small PCB with minimal coupling for a massive multiple input sensor network. The two antennas are planar inverted-F antennas (PIFA) that ar... This article describes the design and simulation of a pair of antennas on a small PCB with minimal coupling for a massive multiple input sensor network. The two antennas are planar inverted-F antennas (PIFA) that are fed with microstrip feed lines. The critical design factors are minimizing mass while creating ISM band and GPS L1 band antennas and developing data transmission schemes for maximum usage of all communication channels. The designed board is a 60 mm diameter, 0.6 mm thick circular FR4 board that weighs approximately 5 g. 展开更多
关键词 ANTENNA environmental sensing Remote sensing Massive multiple input network
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A multiple case study on the cooperative governance model of treating environmental deterioration
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作者 Sheng Li Hu Jian +1 位作者 Ling Zhou Li Qiu 《Chinese Journal of Population,Resources and Environment》 2021年第1期56-64,共9页
Managing the acute problem of environmental deterioration due to the industrialization of modern China is necessary.Using three cases from a theoretical perspective of procedure-structure,this study explored how envir... Managing the acute problem of environmental deterioration due to the industrialization of modern China is necessary.Using three cases from a theoretical perspective of procedure-structure,this study explored how environmental deterioration is governed in three circumstances.Research findings revealed that the pattern to treat the worsening environment is associated closely with individual-specific circumstances,and thus three patterns of governance are developed:bureaucratic,contractual,and network-based cooperatives.The cases and the results are described the advantages and disadvantages of these models are discussed.Suggestions on how to more effectively manage these urgent problems are as follows:first,the governance must fit the circumstance,namely,its physical,biological,and social attributes;second,the regulations and conditions regarding the government-dominated pattern are came up from the perspective of mega-governance,mutual trust contracts,benefit sharing,and social capital;and third,the government should abandon the pattern based on the single subject and adopt a plural subject governance model to integrate all the relevant forces to facilitate the attainment of benign environmental governance. 展开更多
关键词 Procedure-structure environmental cooperative governance Model multiple case study
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Novel ensemble learning based on multiple section distribution in distributed environment
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作者 Fang Min 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第2期377-380,共4页
Because most ensemble learning algorithms use the centralized model, and the training instances must be centralized on a single station, it is difficult to centralize the training data on a station. A distributed ense... Because most ensemble learning algorithms use the centralized model, and the training instances must be centralized on a single station, it is difficult to centralize the training data on a station. A distributed ensemble learning algorithm is proposed which has two kinds of weight genes of instances that denote the global distribution and the local distribution. Instead of the repeated sampling method in the standard ensemble learning, non-balance sampling from each station is used to train the base classifier set of each station. The concept of the effective nearby region for local integration classifier is proposed, and is used for the dynamic integration method of multiple classifiers in distributed environment. The experiments show that the ensemble learning algorithm in distributed environment proposed could reduce the time of training the base classifiers effectively, and ensure the classify performance is as same as the centralized learning method. 展开更多
关键词 distributed environment ensemble learning multiple classifiers combination.
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Advancement Towards Spatial Justice:The Barrier-Free Environment Construction from a Gender Perspective
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作者 张万洪 赵金曦 NI Weisi(Translated) 《The Journal of Human Rights》 2024年第2期306-324,共19页
Space is both a product and a producer of social relations.In the spatial domain,gender blindness has long existed,limiting women’s rights of access to and use of space,leading to structural oppression of women’s ri... Space is both a product and a producer of social relations.In the spatial domain,gender blindness has long existed,limiting women’s rights of access to and use of space,leading to structural oppression of women’s rights,and giving rise to new gender inequalities.The barrier-free environment construction has the functions of eliminating physical barriers and generating societal norms,and when combined with social changes,can facilitate justice correction across multiple dimensions.However,barrier-free environment construction itself,as a means of justice correction,also suffers from gender blindness.There remains room for improvement in the areas of facility construction,information exchange,and social services within the realm of barrier-free environments.In response to this phenomenon,gender equality offers a new critical perspective.Therefore,integrating a gender perspective into the barrier-free environment construction,focusing on the spatial rights of women,especially groups with multiple vulnerabilities,such as disabled women and elderly women,can contribute to the advancement towards spatial justice. 展开更多
关键词 barrier-free environment construction gender equality spatial justice multiple vulnerabilities
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Cooperative Multi-Agent Control for Autonomous Ship Towing Under Environmental Disturbances 被引量:1
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作者 Zhe Du Rudy R.Negenborn Vasso Reppa 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2021年第8期1365-1379,共15页
Among the promising application of autonomous surface vessels(ASVs)is the utilization of multiple autonomous tugs for manipulating a floating object such as an oil platform,a broken ship,or a ship in port areas.Consid... Among the promising application of autonomous surface vessels(ASVs)is the utilization of multiple autonomous tugs for manipulating a floating object such as an oil platform,a broken ship,or a ship in port areas.Considering the real conditions and operations of maritime practice,this paper proposes a multi-agent control algorithm to manipulate a ship to a desired position with a desired heading and velocity under the environmental disturbances.The control architecture consists of a supervisory controller in the higher layer and tug controllers in the lower layer.The supervisory controller allocates the towing forces and angles between the tugs and the ship by minimizing the error in the position and velocity of the ship.The weight coefficients in the cost function are designed to be adaptive to guarantee that the towing system functions well under environmental disturbances,and to enhance the efficiency of the towing system.The tug controller provides the forces to tow the ship and tracks the reference trajectory that is computed online based on the towing angles calculated by the supervisory controller.Simulation results show that the proposed algorithm can make the two autonomous tugs cooperatively tow a ship to a desired position with a desired heading and velocity under the(even harsh)environmental disturbances. 展开更多
关键词 Cooperative control environmental disturbances multiple autonomous vessels robust control ship towing
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Sick Neighborhood Syndrome: Population with Multiple Chemical Sensitivity Adjacent to Bioethanol Distillery
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作者 Eduardo Maturano Bryan Mac Lean +2 位作者 Flavia Silvina Difilippo Juan Manuel Laino Medardo Avila-Vazquez 《Journal of Biosciences and Medicines》 2022年第4期87-98,共12页
The population of a neighborhood in the city of Córdoba presents general irritant symptoms since a bioethanol distillery began to operate there, from which formaldehyde, toluene, xylene mainly emanate. At the req... The population of a neighborhood in the city of Córdoba presents general irritant symptoms since a bioethanol distillery began to operate there, from which formaldehyde, toluene, xylene mainly emanate. At the request of the community, collective environmental health was evaluated with a cross-sectional study of prevalence of these conditions. 53% of the residents reported respiratory disorders, conjunctivitis 31%, headaches 27%, dermatitis 23% and dyspepsia 22%. 57% of children aged 6 - 7 use bronchodilators (an indicator of asthma). 66% of the population has one of these conditions, 46% has two and 26% has three;children are the most affected. The results coincide with the Consensus on Multiple Chemical Sensitivity Syndrome in that it is reproducible by repeated chemical exposure, is chronic and does not improve without eliminating exposure, affecting multiple organs and systems. 14.8% of newborns feature malformations, while in the rest of the city, only 1.7% did. Similar to the Sick Building Syndrome, the collective health picture found suggests a “Sick Neighborhood Syndrome”. 展开更多
关键词 multiple Chemical Sensitivity environmental Exposure Air Pollution environmental Health FORMALDEHYDE
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Modeling and simulation of torpedo acoustic homing trajectory with multiple targets
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作者 GU Hao KANG Feng-ju NIE Wei-dong 《Journal of Marine Science and Application》 2006年第2期30-35,共6页
The characteristics of a torpedo's acoustic homing trajectory with multiple targets were studied. The differential equations of torpedo motion were presented based on hydrodynamics. The Fourth order Runge-Kutta metho... The characteristics of a torpedo's acoustic homing trajectory with multiple targets were studied. The differential equations of torpedo motion were presented based on hydrodynamics. The Fourth order Runge-Kutta method was used to solve these equations. Derived from sonar equations and Snell' s law, a simple virtual underwater acoustic environment was established for simulating the torpedo homing process. The Newton iteration method was used to calculate homing range and ray tracing was approximated by pieccwise line, which takes into consideration distortions cause by temperature, pressure, and salinity in a given sea area. The influence of some acoustic warfare equipment disturb the torpedo homing process in certain circumstances, including decoys and jammers, was alsotaken into account in simulations. Relative target identification logic and homing control laws were presented. Equal consideration during research was given to the requirements of rcal-timeactivity as well as accuracy. Finally, a practical torpedo homing trajectory simulation program was developed and applied to certain projects. 展开更多
关键词 TORPEDO virtual underwater acoustic environment acoustic homing trajectory multiple targets distribute interaction simulation (DIS)
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RESEARCH ON INDOOR ELECTROMAGNETIC RADIATION FIELD OF MULTIPLE ANTENNA SYSTEM
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作者 Ma Li Lu Yanhui +1 位作者 Zou Peng Zhou Xiaoping 《Journal of Electronics(China)》 2012年第5期400-407,共8页
The complexity of the indoor environment brings great challenges to predict the electromagnetic radiation field of multiple antenna systems. Based on the Finite Difference Time Domain (FDTD) algorithm, using the mobil... The complexity of the indoor environment brings great challenges to predict the electromagnetic radiation field of multiple antenna systems. Based on the Finite Difference Time Domain (FDTD) algorithm, using the mobile phone shielding device as the multiple antenna systems example, the mobile phone shielding device's indoor electromagnetic radiation field is researched by measurment method and simulation method. The effectivity of prediction method is verified by comparing the prediciton results with the measurment results. About 80% of the error can be controlled less than dB. The quantitative research has certain guiding significance to the prediction of the multiple antenna systems radio wave propagation. 展开更多
关键词 Electromagnetic radiation field multiple antenna systems Field intensity prediction Finite Difference Time Domain (FDTD) Indoor environment
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Contribution of Multiple Cropping Systems to Greenhouse Gas Mitigation in the Municipality of Abomey-Calavi in Southern Benin
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作者 Vidédji Naéssé Adjahossou Baï Sêdami Adjahossou +4 位作者 Outéndé Toundou Babacar Thioye Dossou Firmin Adjahossou Julien Gaudence Mahutin Djego Michel Boko 《Agricultural Sciences》 2022年第2期117-129,共13页
In the world at large, while agricultural yields are increasing with constant land area, in Sub-Saharan Africa, more land is needed to increase production. In this region of Africa, agriculture therefore remains essen... In the world at large, while agricultural yields are increasing with constant land area, in Sub-Saharan Africa, more land is needed to increase production. In this region of Africa, agriculture therefore remains essentially extensive and contributes to environmental degradation, especially deforestation. Thus, the objective of this research is to assess and compare the quantities of greenhouse gases produced by multiple and mono-specific cropping systems. To this end, the quantity of greenhouse gases (GHG) produced by several cropping systems installed on an experimental farm in Kpotomey in the municipality of Abomey-Calavi (Benin) was estimated. The estimation of GHG quantities was made on the basis of IPCC work and data from the experiments carried out. Comparisons were made between mono-specific crops and multiple crops. The results show that the quantities of GHG emitted per ton of production are more or less identical and vary on average from 0.6 to 0.11 teqCO<sub>2</sub>. However, the advantage of multiple cropping systems is that they reduce the clearing of new land and thus avoid about 31.5 tons of CO<sub>2</sub> if the plant formation to be replaced was a forest. Multiple cropping with moderate fertilization in the presence of organic matter increases production while preserving the environment. 展开更多
关键词 multiple Cropping System Reduction of GHG DEFORESTATION environment AGROECOLOGY
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The Effect of Molybdenum Rate in Soil on Multiple Sclerosis:Case Study New Zealand and Isfahan(A Review)
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作者 Sousan Norouzi Mobarakeh 《Journal of Geological Research》 2020年第3期52-55,共4页
Scientists believe that Multiple Sclerosis disease occurs because of some of environmental factors such as soil pollution.In this paper,relationship among Multiple Sclerosis disease,Molybdenum and soil properties in N... Scientists believe that Multiple Sclerosis disease occurs because of some of environmental factors such as soil pollution.In this paper,relationship among Multiple Sclerosis disease,Molybdenum and soil properties in New Zealand and Isfahan,Iran has been investigated and from the point of view of nature of the soil for example pH and the distribution of disease was observed similarities. 展开更多
关键词 environmental factors multiple sclerosis New Zealand ISFAHAN MOLYBDENUM SOIL POLLUTION
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Research on Novel and Innovative Music Education Model based on Multiple Intelligences Theory and New Media
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作者 Li Xu Fei Li 《International Journal of Technology Management》 2015年第10期26-28,共3页
With the rapid development of new media and education theories, the combination of the two aspects is urgently needed. In this paper, we conduct theoretical analysis on novel and innovative music education model based... With the rapid development of new media and education theories, the combination of the two aspects is urgently needed. In this paper, we conduct theoretical analysis on novel and innovative music education model based on multiple intelligences theory and new media. The theory of multiple intelligence education concept is to change too pay attention to the tendency of knowledge. The novelty of new media, not only in the form of new information carrier and communication channel, also include technological progress brings new propagation mode. Our proposed combined model will enhance the performance of the current teaching activity which is meaningful. 展开更多
关键词 Music Education New Media multiple Intelligences Multimedia environment.
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The Environmental Impact of Plastic Waste
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作者 Boyu Jiang Jiming Yu Yihang Liu 《Journal of Environmental & Earth Sciences》 2020年第2期26-35,共10页
The pollution caused by disposable plastic products is becoming moreand more serious, and “plastic limit” has become a global consensus. Thisarticle mainly discusses the pollution problem from the following aspects:... The pollution caused by disposable plastic products is becoming moreand more serious, and “plastic limit” has become a global consensus. Thisarticle mainly discusses the pollution problem from the following aspects:Integrate all relevant important indicators to establish a multiple regressionmodel of the maximum amount of disposable plastic waste to estimatethe maximum amount of disposable waste in the future without causingfurther damage to the environment;Establish an environmental safety levelevaluation model and analyze the impact of plastic waste on environmentalsafety;Try to set the lowest level target that can be achieved by globalwaste at this stage, and conduct correlation analysis on the impact ofhumans, enterprises, and the environment;Select several countries basedon their comprehensive strengths, conduct a comparative analysis of theirplastic production, economic strength, and environment, and try to exploretheir responsibilities. 展开更多
关键词 multiple egression Fuzzy hierarchy Plastic waste environmental safety
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Water resources optimization and eco-environmental protection in Qaidam Basin
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作者 FANG Chuang-lin~1, BAO Chao~2 (1. Institute of Geographic Sciences and Natural Resources Research, CAS, Beijing 100101, China 2. Dept. of Geography, Peking University, Beijing 100871, China) 《Journal of Geographical Sciences》 SCIE CSCD 2001年第2期231-238,共8页
In order to realize sustainable development of the arid area of Northwest China, rational water resources exploitation and optimization are primary prerequisites. Based on the essential principle of sustainable develo... In order to realize sustainable development of the arid area of Northwest China, rational water resources exploitation and optimization are primary prerequisites. Based on the essential principle of sustainable development, this paper puts forward a general idea on water resources optimization and eco-environmental protection in Qaidam Basin, and identifies the competitive multiple targets of water resources optimization. By some qualitative methods such as Input-output Model & AHP Model and some quantitative methods such as System Dynamics Model & Produce Function Model, some standard plans of water resources optimization come into being. According to the Multiple Targets Decision by the Closest Value Model, the best plan of water resources optimization, eco-environmental protection and sustainable development in Qaidam Basin is finally decided. 展开更多
关键词 water resources optimization multiple Targets Decision by the Closest Value Model eco-environmental protection Qaidam Basin
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环境规制、数字赋能对产业结构升级的影响及机理 被引量:3
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作者 马海良 顾莹莹 +1 位作者 黄德春 贺正齐 《中国人口·资源与环境》 CSCD 北大核心 2024年第3期124-136,共13页
当前中国经济转型的重要路径为“绿色优先,数字赋能”。为探究绿色化与数字化在产业层面能否实现协同发展,该研究利用全国283个地级市的面板数据,验证数字经济在产业结构绿色转型过程中发挥的调节效应。首先使用多重门槛检验来寻找环境... 当前中国经济转型的重要路径为“绿色优先,数字赋能”。为探究绿色化与数字化在产业层面能否实现协同发展,该研究利用全国283个地级市的面板数据,验证数字经济在产业结构绿色转型过程中发挥的调节效应。首先使用多重门槛检验来寻找环境规制与产业结构调整之间的非线性关系,在利用高阶函数进行拟合的基础上,加入产业数字化与数字产业化两大调节变量剖析环境规制和数字赋能的协同作用。研究结果表明:①环境规制对于产业结构合理化不存在明显影响,但对产业结构高级化存在单门槛效应,即当环境规制力度越过门槛值后能够实现环境改善与产业结构升级共赢。②产业数字化与环境规制并行使得产业结构合理化出现了双门槛效应,随着两者融合程度加深,可通过逐步减轻环境规制力度来实现协同发展;但产业数字化与环境规制并行使得产业结构高级化的单门槛效应消失,交互项系数显著为正但并不稳定。③数字产业化与环境规制并行对于产业结构合理化不存在显著影响,但对于产业结构高级化产生了单门槛效应,且随着两者融合程度加深,生态与产业协同发展的强度区间会逐渐扩大。④从局部地区的异质性回归结果来看,主要结论仍然可以得到验证,但发现经济发达片区存在向欠发达片区进行污染转移的现象。据此,该研究提出,顶层设计过程中应考虑地方环境治理的短视行为及各区域产业层次的客观差异,引导发达地区政府更加关注绿色技术创新的长期驱动力,促进“绿色共识”与发展目标深度融合。 展开更多
关键词 环境规制 数字赋能 产业结构调整 多重门槛 “两化”融合
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道阻且长,“行”者将“治”:公共事务的行为治理之道 被引量:4
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作者 张书维 汪彦 秦枭童 《广西师范大学学报(哲学社会科学版)》 2024年第1期50-68,共19页
行为治理是将行为科学洞见应用于公共治理场域而发展出的治理新模式。行为治理关注政府、组织和公民三类核心治理主体在互动过程中的心理、认知及行为规律,并分析治理主体互动关系的元素特征如何影响主体行为,同时更全面地考虑环境因素... 行为治理是将行为科学洞见应用于公共治理场域而发展出的治理新模式。行为治理关注政府、组织和公民三类核心治理主体在互动过程中的心理、认知及行为规律,并分析治理主体互动关系的元素特征如何影响主体行为,同时更全面地考虑环境因素对微观行为的影响,以及个体行为汇聚为集体行动并产生更广泛治理结果的机制。行为治理呼吁治理工具的组合运用,强调“助推”和“助力”两大行为工具的内部融通,重视行为工具与传统工具的外部联动。行为治理脱胎于行为公共管理和行为公共政策,更强调各主体间的互动性,更重视环境的复杂性,更主张治理工具在内外部及各层次上的融会贯通。行为治理紧扣治理主体的行为要素,自下而上、从微观到宏观,丰富国家治理现代化的思想库和工具箱。 展开更多
关键词 行为治理 公共管理 公共政策 治理现代化 环境作用 工具组合
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通信受限条件下多无人机协同环境覆盖路径规划
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作者 陈洋 周锐 《中国惯性技术学报》 EI CSCD 北大核心 2024年第3期273-281,共9页
多无人机协同覆盖旨在有效分配多个无人机任务,实现给定区域的快速、高效全覆盖。然而,在现实应用场景中常常因为无人机之间距离超出通信范围,信号传输受阻,导致无人机之间的协作和信息交互面临极大挑战。为此,提出一种基于Deep Q Netwo... 多无人机协同覆盖旨在有效分配多个无人机任务,实现给定区域的快速、高效全覆盖。然而,在现实应用场景中常常因为无人机之间距离超出通信范围,信号传输受阻,导致无人机之间的协作和信息交互面临极大挑战。为此,提出一种基于Deep Q Networks(DQN)的多无人机路径规划方法。采用通信中断率和最大通信中断时间两个指标来评价路径质量,通过构建与指标相关的奖励函数,实现了无人机团队的自主路径决策。仿真实验表明,所提方法在最短路径上可以与传统优化算法效果保持一致,权衡路径下在增加20%路径长度的情况下可以降低80%通信中断率,在全通信路径下则可以实现100%的全过程连接通信,因此可以根据不同的通信环境生成高效覆盖所有环境节点的路径。 展开更多
关键词 环境覆盖 多无人机 通信约束 深度Q网络 路径规划
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基于环境DNA技术的黄河流域下游山区河流大型底栖动物群落多样性特征及其影响要素分析 被引量:1
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作者 赵茜 潘福霞 +2 位作者 李斌 臧小苗 丁森 《湖泊科学》 EI CAS CSCD 北大核心 2024年第2期523-535,共13页
河流生物群落组成由多种环境因子共同作用形成,但其影响机制尚不清楚。本研究基于环境DNA技术,选择黄河流域下游4条山区河流(锦绣川、锦阳川、锦云川和三川汇合后河流)的10个样点开展大型底栖动物监测。结果发现:不同溪段水质状况有所差... 河流生物群落组成由多种环境因子共同作用形成,但其影响机制尚不清楚。本研究基于环境DNA技术,选择黄河流域下游4条山区河流(锦绣川、锦阳川、锦云川和三川汇合后河流)的10个样点开展大型底栖动物监测。结果发现:不同溪段水质状况有所差异,锦云川盐化程度(以电导率EC表征)和营养盐浓度较高,锦阳川抗生素浓度较高,锦绣川水质较好。山区河流大型底栖动物群落组成差异明显,锦绣川以水生昆虫为主,软体动物占比较低。其中,昆虫纲的大蚊(Tipula abdominalis)、天角蜉(Uracanthella punctisetae)和寡毛纲的顠体虫(Aeolosoma sp.)是造成锦绣川与其他河流大型底栖动物群落结构差异的关键物种。冗余分析和变差分解分析结果表明,盐化、营养盐和抗生素均会对大型底栖动物群落组成产生影响。其中,EC的解释率为22.86%,营养盐中的TP、NH_(3)-N和TN的解释率分别为20.12%、13.25%和7.81%;此外,盐化可与营养盐和抗生素通过耦合效应对大型底栖动物群落组成产生影响,贡献率分别为21.60%和16.20%;抗生素与营养盐的贡献率为19.60%。逐步判别回归模型结果显示,Margalef指数(d)受盐化(EC)和营养盐(NH_(3)-N和NO_(3)^(-)-N)的共同影响;随着河流中EC浓度升高,d与NH_(3)-N之间的正响应关系及其与NO_(3)^(-)-N之间的负响应关系显著增强。因此,多环境因子对水生生物的影响不容忽视,在大型底栖动物生物多样性保护中应关注各类环境因子的影响贡献。 展开更多
关键词 环境DNA 多环境因子 耦合效应 大型底栖动物 山区河流 黄河流域下游
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网络视角下京津冀区域环境协同治理现状、成效及对策 被引量:2
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作者 李梅 杨萍 张敏 《中国环境管理》 2024年第1期82-87,81,共7页
当前,区域环境治理已进入多元行动主体之间广泛而深度合作的时代,网络特征越发明显。本文以京津冀区域为研究对象,运用网络治理、协同治理等相关理论,从府际关系网络、跨区域治理组织、合作协议体系、多主体协同效应、机制创新等方面总... 当前,区域环境治理已进入多元行动主体之间广泛而深度合作的时代,网络特征越发明显。本文以京津冀区域为研究对象,运用网络治理、协同治理等相关理论,从府际关系网络、跨区域治理组织、合作协议体系、多主体协同效应、机制创新等方面总结网络视角下环境协同治理现状及成效;结合存在问题,从治理模式转型、跨区域统筹能力、跨界协调机制市场化治理工具、政府网络管理能力五个方面提出对策建议,为京津冀区域环境治理体系和治理能力现代化提供科学依据。 展开更多
关键词 京津冀区域 环境协同治理 治理网络 多元共治
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基于多环境因素分析的猪舍温湿度预测模型
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作者 朱佳明 孙彬 +4 位作者 蒲施桦 潘学民 徐顺来 胡彬 齐仁立 《华南农业大学学报》 CAS CSCD 北大核心 2024年第5期709-721,共13页
【目的】针对环控设备调控滞后导致的密闭猪舍内温湿度波动大问题,提出合适的多元时间序列温湿度预测模型。【方法】采用皮尔逊相关性分析确定采集到的12种环境因子的相关性,初步筛选模型的输入特征。对已筛选的输入特征归一化,消除数... 【目的】针对环控设备调控滞后导致的密闭猪舍内温湿度波动大问题,提出合适的多元时间序列温湿度预测模型。【方法】采用皮尔逊相关性分析确定采集到的12种环境因子的相关性,初步筛选模型的输入特征。对已筛选的输入特征归一化,消除数据尺度的影响,选取DDGCRN、长短期记忆网络、支持向量回归和随机森林模型,对模型预测结果实例验证,筛选出性能最好的模型。【结果】筛选确定了温湿度预测模型的输入特征。经对比验证,DDGCRN模型预测精度最高,其预测温度和湿度的平均绝对误差分别为0.079和0.458,均方根误差分别为0.134和0.719,平均绝对百分比误差分别为0.392%和0.675%。模型输入配置比较分析表明,过多的输入特征并不能使得模型的预测能力提高,反而可能降低,且不同类型的模型以及不同的预测目标都有不同的合适的输入特征。【结论】使用DDGCRN温湿度预测模型对舍内的温湿度变换可以起到提前警告作用,为精准控制养殖环境温湿度提供参考。 展开更多
关键词 多环境因素 密闭猪舍 温湿度 预测模型 相关性分析
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政府环境信息披露提升环境治理成效
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作者 时培豪 吴传清 黄庆华 《经济理论与经济管理》 北大核心 2024年第2期17-30,共14页
本文基于2010—2020年污染物排放数据,采用多重差分模型,实证检验政府披露环境信息对微观主体环境治理的影响。研究发现:政府提高环境信息披露强度会激励企业开展环境整治行动,降低污染物排放总量,提升环境治理成效。政府环境信息披露... 本文基于2010—2020年污染物排放数据,采用多重差分模型,实证检验政府披露环境信息对微观主体环境治理的影响。研究发现:政府提高环境信息披露强度会激励企业开展环境整治行动,降低污染物排放总量,提升环境治理成效。政府环境信息披露发挥治理效应主要通过加大地区环保执法力度和强化公共环境监督两种途径实现。受政府环境信息披露的影响,企业改善环境治理成效的同时会提升创新能力、经营效率和财务绩效。 展开更多
关键词 环境信息披露 环境治理 经济高质量发展 多重差分模型
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