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Fine-grained grid computing model for Wi-Fi indoor localization in complex environments
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作者 Yan Liang Song Chen +1 位作者 Xin Dong Tu Liu 《Journal of Electronic Science and Technology》 EI CAS CSCD 2024年第1期42-52,共11页
The fingerprinting-based approach using the wireless local area network(WLAN)is widely used for indoor localization.However,the construction of the fingerprint database is quite time-consuming.Especially when the posi... The fingerprinting-based approach using the wireless local area network(WLAN)is widely used for indoor localization.However,the construction of the fingerprint database is quite time-consuming.Especially when the position of the access point(AP)or wall changes,updating the fingerprint database in real-time is difficult.An appropriate indoor localization approach,which has a low implementation cost,excellent real-time performance,and high localization accuracy and fully considers complex indoor environment factors,is preferred in location-based services(LBSs)applications.In this paper,we proposed a fine-grained grid computing(FGGC)model to achieve decimeter-level localization accuracy.Reference points(RPs)are generated in the grid by the FGGC model.Then,the received signal strength(RSS)values at each RP are calculated with the attenuation factors,such as the frequency band,three-dimensional propagation distance,and walls in complex environments.As a result,the fingerprint database can be established automatically without manual measurement,and the efficiency and cost that the FGGC model takes for the fingerprint database are superior to previous methods.The proposed indoor localization approach,which estimates the position step by step from the approximate grid location to the fine-grained location,can achieve higher real-time performance and localization accuracy simultaneously.The mean error of the proposed model is 0.36 m,far lower than that of previous approaches.Thus,the proposed model is feasible to improve the efficiency and accuracy of Wi-Fi indoor localization.It also shows high-accuracy performance with a fast running speed even under a large-size grid.The results indicate that the proposed method can also be suitable for precise marketing,indoor navigation,and emergency rescue. 展开更多
关键词 Fine-grained grid computing (FGGC) Indoor localization Path loss Random forest Reference points(RPs)
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Discussion on the relationship between Construction of Forest Towns and Reform & Development of State-owned Forest Farms
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作者 Sha Qiao 《Frontiers Research of Architecture and Engineering》 2018年第4期113-116,共4页
In recent years, China's social economy has continued to develop. While paying attention to the pursuit of the economy, people are paying more and more attention to the pursuit of quality of life. China has vast t... In recent years, China's social economy has continued to develop. While paying attention to the pursuit of the economy, people are paying more and more attention to the pursuit of quality of life. China has vast territory and abundant resources, forest resources are particularly rich, in order to make full use of forest resources and regulate the use and protection of forests, China has promoted the development of forestry by deepening the construction and reform of state-owned forest farms, and using forest resources to obtain benefits to meet people's living needs. This paper explores the necessity and advantages of building a forest town by analyzing the reform and development situation of state-owned forest farms. 展开更多
关键词 forest TOWNS state-owned forest farms REFORM and DEVELOPMENT
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A study on state-owned forest area stakeholders' behavior
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作者 ZHANG Ai-mei CHEN Shao-zhi +2 位作者 WU Wei-hong LI Wen-yu WANG Yang-yang 《Ecological Economy》 2014年第2期164-171,共8页
The development of state-owned forest area plays a very important role in the development of Chinese forest industry, and even in the construction of national economy. As the backbone of Chinese forestry development, ... The development of state-owned forest area plays a very important role in the development of Chinese forest industry, and even in the construction of national economy. As the backbone of Chinese forestry development, it contributes to Chinese economic development, ecological environment protection and social progress. How to balance all stakeholders' interest and behaviors remains as one of the focuses in the study of sustainable development of forest areas. On this basis, researches were carried out and described in the paper. Firstly, the paper goes through the concept and scope of state-owned forest area in China; Secondly, it defines the stakeholders of state-owned forest area, and discusses over the problems in stakeholders' behaviors from the aspect of responsibility, rights and interests; and Finally, it designs the stakeholders' behaviors on the basis of existing problems and provides constructive suggestions on deeper reform of state-owned forest areas. 展开更多
关键词 stakeholders' behaviors state-owned forest area China
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Local perceptions of the conversion of cropland to forestland program in Jiangxi, Shaanxi, and Sichuan, China 被引量:1
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作者 Guangyu Wang Oliver Z.Ma +7 位作者 Liguo Wang Anil Shrestha Baozhang Chen Feng Mi Shirong Liu Xiaomin Guo Sarah Eshpeter John L.Innes 《Journal of Forestry Research》 SCIE CAS CSCD 2019年第5期1833-1847,共15页
Numerous land-use policies have been implemented in China in recent decades for ecological restoration and conservation to reduce environmental disasters and promote environmental sustainability.Many of these policies... Numerous land-use policies have been implemented in China in recent decades for ecological restoration and conservation to reduce environmental disasters and promote environmental sustainability.Many of these policies follow a top-down approach to implementation and as such,emphasize the hierarchical control within government structures.An understanding of local perceptions of land-use policies is important if the disconnect between policy makers and the target population is to be reduced and if program support is to improve.This study aimed to help improve local implementation,attitude toward,and engagement by examining the influence of socio-economic characteristics on the target population’s(local farmers)perception of the conversion of cropland to forestland program(CFPP)land use policy in Jiangxi,Sichuan,and Shaanxi provinces.It uses logistical regression models,with robust aspects of perception including confidence,support,transparency,prospects,fairness,and willingness to participate.Results indicate that social aspects as well as economic aspects are most important in influencing farmers’perceptions towards the CFPP.The farmers who have received technical support,rural male habitants,educated,and non-middle-aged farmers exhibit more positive perceptions of the program and are much more likely to support it,whereas farmers without any technical support or formal education,and female and middle-aged farmers are less likely to support the program.Importantly,this study also reveals the differences in responses,experiences and perceptions of the farmers living across different provinces.These empirical results provide insight into the influence of socio-economic characteristics on the perception of farmers towards land-use policies,which has important implications for designing targeted policy instruments and increasing farmer support for these policies.This knowledge can be harnessed and further evaluated in future research to improve citizen engagement,support,and understanding in order to help ecological restoration and conservation objectives be more effectively achieved. 展开更多
关键词 forest policy ECOLOGICAL restoration local perception Social sustainability Land-use and change China
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Feature Selection with a Local Search Strategy Based on the Forest Optimization Algorithm 被引量:2
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作者 Tinghuai Ma Honghao Zhou +3 位作者 Dongdong Jia Abdullah Al-Dhelaan Mohammed Al-Dhelaan Yuan Tian 《Computer Modeling in Engineering & Sciences》 SCIE EI 2019年第11期569-592,共24页
Feature selection has been widely used in data mining and machine learning.Its objective is to select a minimal subset of features according to some reasonable criteria so as to solve the original task more quickly.In... Feature selection has been widely used in data mining and machine learning.Its objective is to select a minimal subset of features according to some reasonable criteria so as to solve the original task more quickly.In this article,a feature selection algorithm with local search strategy based on the forest optimization algorithm,namely FSLSFOA,is proposed.The novel local search strategy in local seeding process guarantees the quality of the feature subset in the forest.Next,the fitness function is improved,which not only considers the classification accuracy,but also considers the size of the feature subset.To avoid falling into local optimum,a novel global seeding method is attempted,which selects trees on the bottom of candidate set and gives the algorithm more diversities.Finally,FSLSFOA is compared with four feature selection methods to verify its effectiveness.Most of the results are superior to these comparative methods. 展开更多
关键词 FEATURE selection local SEARCH strategy forest optimization FITNESS function
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A pattern for partnership between LMDH and Perhutani to enhance local community prosperity and preserve the forest:a case study at RPH Besowo,Kediri Regency,Indonesia 被引量:1
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作者 Rustinsyah 《Chinese Journal of Population,Resources and Environment》 2015年第3期265-271,共7页
The deforestation in Indonesia is already alarming.One of the strategies used by the government to overcome forest deforestation is social forestry.This program is called PHBM(Pengelolaan Hutan Bersama Masyarakat/Join... The deforestation in Indonesia is already alarming.One of the strategies used by the government to overcome forest deforestation is social forestry.This program is called PHBM(Pengelolaan Hutan Bersama Masyarakat/Joint Forest Management) which is basically a partnership program.This study aims at describing the partnership program between a local organization(i.e.LMDH) and a government unit(i.e.RPH of Perhutani) within the PHBM program.The objectives of this study are to(a) describe the model of partnerships between LMDH and RPH Besowo for sustainable forest management and local community empowerment;(b) determine the contribution of the forest to the national economy and rural household income;and(c) determine the obstacles commonly found in Besowo forest that have to be faced during the implementation of the partnerships.The study shows that with good partnership between these two units,the prosperity of the local community can be enhanced and the forest preservation can be maintained.The model of the partnerships in this particular area in Indonesia is expected to be applicable as well in other rural areas in Indonesia,as well as in other developing countries. 展开更多
关键词 developing countries forest sustainable management local COMMUNITY local COMMUNITY EMPOWERMENT PARTNERSHIP social forestry
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The Role and Effectiveness of Local Institutions in the Management of Forest Biodiversity in New Dabaga-Ulongambi Forest Reserve,Iringa Region-Tanzania 被引量:1
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作者 Richard A.Giliba Zacharia J.Lupala +2 位作者 Canisius J.Kayombo Yobu M.Kiungo Patrick Mwendwa 《Chinese Journal of Population,Resources and Environment》 2012年第1期111-115,共5页
This paper examines the role and effectiveness of locacal institutions in the management of forest biodiversity in New Dabaga-Ulongambi Forest Reserve, Tanzania. Data were obtained through questionnaires, interviews, ... This paper examines the role and effectiveness of locacal institutions in the management of forest biodiversity in New Dabaga-Ulongambi Forest Reserve, Tanzania. Data were obtained through questionnaires, interviews, focus group discussions, participatory rural appraisal and field observations. The study revealed that the most remarkable local institutions connected to forest biodiversity management include: Village Natural Resources Man- agement Committee (92%), tree nursery group (79.4%), beekeep- ing groups (61.1%), fish fanning (43.3%), livestock rearing group (33.9%). Main activities carried out by local institutions which directly contribute to the sustainability Of forest reserve include: forest patrols, fire extinguish, preparation of fire breaks, plant- ing of trees along the forest boundaries, creation of awareness, arresting of forest defaulters, participation in income generation activities. For the purpose of realization that local communities are capable of managing forest biodiversity through their traditional institutions, the policy should provide tangible opportunity for local communities to meet their needs as they manage the forests. 展开更多
关键词 local institution participatory forest management forest biodiversity
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Forest cover change and its effects on the livelihood of the dependent local people:the case of Sesheke district of Zambia
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作者 Banda Arnold Sakala Enock Mulenga Mark 《宝鸡文理学院学报(自然科学版)》 CAS 2013年第4期44-49,共6页
Objective-To investigate forest cover change in Masese Local Forest Reserve and its effects on the livelihoods of the dependent communities;to establish the occurrence of forest cover change in Masese Local Forest Res... Objective-To investigate forest cover change in Masese Local Forest Reserve and its effects on the livelihoods of the dependent communities;to establish the occurrence of forest cover change in Masese Local Forest Reserve;to determine the extent of forest cover change in Masese from 1990to 2005;to determine the tree species that have been affected by forest cover change in Masese; and to assess the effects of forest cover change on the livelihoods of the dependent communities. Methods-Interviews and questionnaire were conducted with a proportion of 36households from Maondo and 84households from Mulimambango settlements.Scenes of landsat images of 1990,2000, 2005and Earth Google image for Masese were used for map analysis.Also remote sensing was used to analyze landsat images and Google image to detect forest and non-forest classes.Results and Conclusion-Forest cover change has adverse implication on the provision of wood forest products and nonwood forest products to the dependent local communities.The declining status of dominant Baikiaea Forest that has exploitable species for building materials and fuel wood has affected the livelihoods of the dependent local communities.There is also increased cost and shortage of fire wood and building materials due to deforestation in Masese Forest Reserve. 展开更多
关键词 forest cover change local communities livelihoods Masese forest reserve dependent communities
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Estimation of Economic Value of Agroforestry Systems at the Local Scale in Eastern Sudan
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作者 Bashir Awad El Tahir Akshay Vishwanath 《Journal of Geoscience and Environment Protection》 2015年第9期38-56,共19页
The objective of this paper is to institute farmers’ own perceptions of the on-and off-farm benefits of agroforestry systems (AFS). Using use value approach, this paper presents empirical evidence on the use values o... The objective of this paper is to institute farmers’ own perceptions of the on-and off-farm benefits of agroforestry systems (AFS). Using use value approach, this paper presents empirical evidence on the use values of three types of AFS practiced by the refugees and their hosting communities in Eastern Sudan. The total economic value (TEV) was applied as a framework to estimate the ecosystem values of AFS under study. Goods values were estimated using specific market values, while the services values were qualitatively described according to local perceived values of the local communities. Perceived TEV of AFS includes marketable and non-marketable goods and services. The main direct marketable and sustainable high value products include: food, cash crops, firewood, gum, fodder, NTFPs medicine, fodder, and honey. The valuation results reveal that AFS in the project sites have significantly contributed to the livelihoods of the local communities. Overall, the average net direct-use value of marketable products across all sites was estimated at 7,346,000.0 SDG (1,335,636.36 US$) HH/annum. Gum Arabic alone accounted for 38%, followed by sorghum grain and fodder 35%, and cash crops (sesame) 18%. This value would be many time higher if other indirect values (non-marketable) services such as shade, aesthetic and recreation, environmental protection, biodiversity and carbon sequestration are quantified. The goods and services mentioned above provide sustainable income to the farmer directly and viable benefits to the region indirectly. Hence, AFS in the study sites shows the way to reconcile two conflicting goals: short-term food and livelihood needs with long-term environmental conservation and improvement. The study provides evidence that the high local perceived values of AFS in the study sites constitute a central means of livelihood, whereas its contribution to the local economy. The study stresses the need to quantify the monetary values of non-marketed products to consistently account for resource availability and usage to further sound policy decisions. Tenure security, farmer support services and human capital development were major areas identified for policy development. 展开更多
关键词 local PERCEIVED VALUES Marketable PRODUCTS Natural PRODUCTS Gum ARABIC Non-Timber forest PRODUCTS
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Local People's Perception of Forest Resources Conservation in Ekiti State, Nigeria
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作者 Arowosoge Oluwayemisi Grace 《Journal of Environmental Science and Engineering(B)》 2015年第3期132-140,共9页
This study examines local people's perception of forest resources (FR) conservation around two plantation forest reserves (PFR) and two natural forest reserves (NFR) in Ekiti State in order to determine the fac... This study examines local people's perception of forest resources (FR) conservation around two plantation forest reserves (PFR) and two natural forest reserves (NFR) in Ekiti State in order to determine the factors that can contribute to sustainable FR conservation. Questionnaire and interview were used to collect data from 240 respondents. Data were analyzed using descriptive and inferential statistics. 75.0% and 86.1% of respondents around PFR recognized the importance of conserving the FR for economic benefits and biodiversity respectively, while 66.7% would not want the FR conserved for cultural values. 82.9% of respondents around NFR would want the FR conserved for economic benefits, while 74.3% and 66.7% would not want the forest conserved for cultural values and biodiversity respectively. For efficient conservation, participation in forest management and involvement in decision making with means of 3.45 and 3.52 ranked highest in PFR and NFR respectively. Probit regression analysis showed that in PFR and NFR, age, education and income were positively significant to FR conservation (p 〈 0.05). Creating an enabling environment that will make local people appreciate historical cultural values of the forest for tourism is essential for efficient FR conservation in the study area. 展开更多
关键词 forest resources conservation local people perception.
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Comparison of the local pivotal method and systematic sampling for national forest inventories
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作者 Minna Räty Mikko Kuronen +3 位作者 Mari Myllymäki Annika Kangas Kai Mäkisara Juha Heikkinen 《Forest Ecosystems》 SCIE CSCD 2020年第4期716-732,共17页
Background:The local pivotal method(LPM)utilizing auxiliary data in sample selection has recently been proposed as a sampling method for national forest inventories(NFIs).Its performance compared to simple random samp... Background:The local pivotal method(LPM)utilizing auxiliary data in sample selection has recently been proposed as a sampling method for national forest inventories(NFIs).Its performance compared to simple random sampling(SRS)and LPM with geographical coordinates has produced promising results in simulation studies.In this simulation study we compared all these sampling methods to systematic sampling.The LPM samples were selected solely using the coordinates(LPMxy)or,in addition to that,auxiliary remote sensing-based forest variables(RS variables).We utilized field measurement data(NFI-field)and Multi-Source NFI(MS-NFI)maps as target data,and independent MS-NFI maps as auxiliary data.The designs were compared using relative efficiency(RE);a ratio of mean squared errors of the reference sampling design against the studied design.Applying a method in NFI also requires a proven estimator for the variance.Therefore,three different variance estimators were evaluated against the empirical variance of replications:1)an estimator corresponding to SRS;2)a Grafström-Schelin estimator repurposed for LPM;and 3)a Matérn estimator applied in the Finnish NFI for systematic sampling design.Results:The LPMxy was nearly comparable with the systematic design for the most target variables.The REs of the LPM designs utilizing auxiliary data compared to the systematic design varied between 0.74–1.18,according to the studied target variable.The SRS estimator for variance was expectedly the most biased and conservative estimator.Similarly,the Grafström-Schelin estimator gave overestimates in the case of LPMxy.When the RS variables were utilized as auxiliary data,the Grafström-Schelin estimates tended to underestimate the empirical variance.In systematic sampling the Matérn and Grafström-Schelin estimators performed for practical purposes equally.Conclusions:LPM optimized for a specific variable tended to be more efficient than systematic sampling,but all of the considered LPM designs were less efficient than the systematic sampling design for some target variables.The Grafström-Schelin estimator could be used as such with LPMxy or instead of the Matérn estimator in systematic sampling.Further studies of the variance estimators are needed if other auxiliary variables are to be used in LPM. 展开更多
关键词 Auxiliary data Bias local pivotal method Matérn estimator National forest inventory Sampling efficiency Simple random sampling Spatially balanced sampling Systematic sampling Variance
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Contribution of Sumalindo Company:In Managing Forest Resources with Local Communities:Mahakam Ulu-East Kalimantan
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作者 Herman Hidayat Massa Jafar +4 位作者 David A.Sonnenfeld Stephen Wyatt Masatoshi Sasaoka Ndan Imang Martinus Nanang 《Journal of Environmental Science and Engineering(B)》 2022年第4期111-124,共14页
The role of HPH(Forest Logging Concession)in developing rural communities is very significant.SLJ(Sumalindo Lestari Jaya)as HPH company has an important contribution in empowering local communities,especially in openi... The role of HPH(Forest Logging Concession)in developing rural communities is very significant.SLJ(Sumalindo Lestari Jaya)as HPH company has an important contribution in empowering local communities,especially in opening land transportation in the interior and helping to build agriculture and gardens.The existence of Sumalindo company participates in developing forest resource management with local communities,among others,increasing livelihoods,maintaining and developing biodiversity conservation and maintaining climate change.These efforts are in accordance with the regulations of the KLHK(Ministry of Environment and Forestry),that every HPH holder is required(mandatory)to obtain a certificate of“PHAPL”(Sustainable Production Natural Forest Management)and an“eco label”from the Indonesian Eco Label Institute.Besides,it is recommended that the holders of HPH concessions and HTI(Industrial Timber Plantations)have an FSC(Forest Stewardship Council)certificate from the EU(European Union),and must meet three indicator elements,namely economic,social and ecological in SFM(Sustainable Forest Management).This article examines three critical questions that show the role of Sumalindo Company in economic,ecological and social development and managing forest resources with the community as follows:(1)The role of Sumalindo company contributes to the development of road infrastructure in the interior;(2)The role of Sumalindo in improving livelihoods and economic and social empowerment of local communities;(3)The role of Sumalindo with local communities in managing forest resources,including maintaining and developing biodiversity conservation and maintaining climate change. 展开更多
关键词 SLJ economic ecological and social forest resource management PHAPL management FSC local communities
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现代化生态文明建设中的林长制治理探析
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作者 范俊荣 李航 《齐齐哈尔大学学报(哲学社会科学版)》 2024年第5期72-75,81,共5页
林长制将保护发展森林草原资源落实为地方党政领导干部的主体责任,“属地管理,分级负责”作为一种重要的制度,是我国现代化生态文明建设不可或缺的组成部分。林长制以习近平生态文明思想为引领,具有特定的理论基础,全面推行林长制对现... 林长制将保护发展森林草原资源落实为地方党政领导干部的主体责任,“属地管理,分级负责”作为一种重要的制度,是我国现代化生态文明建设不可或缺的组成部分。林长制以习近平生态文明思想为引领,具有特定的理论基础,全面推行林长制对现代化生态文明建设的意义重大。论文通过对林长制治理地方实践的考察,对标林长制有关法律法规、林长制职权范围、林长制考核和激励机制、林长制监督体系,分析林长制治理中存在的问题,最后提出了优化林长制治理的对策。 展开更多
关键词 林长制 生态文明建设 制度创新 地方实践
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耦合DWT-IFLOF的大坝监测数据异常检测算法
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作者 王译羚 丁勇 李登华 《中国农村水利水电》 北大核心 2024年第7期203-209,共7页
基于数据驱动的模型已广泛应用于大坝运行状态建模与短期变形预测等领域中,而监测数据中存在的异常值会削弱甚至破坏数据驱动模型的可信度和鲁棒性。针对上述问题,提出一种耦合DWT-IFLOF的大坝监测数据异常检测算法。首先,采用小波降噪... 基于数据驱动的模型已广泛应用于大坝运行状态建模与短期变形预测等领域中,而监测数据中存在的异常值会削弱甚至破坏数据驱动模型的可信度和鲁棒性。针对上述问题,提出一种耦合DWT-IFLOF的大坝监测数据异常检测算法。首先,采用小波降噪技术减少监测数据集中采集噪声对模型建模的负面干扰。其次设计一种耦合孤立森林(iForest)异常检测算法与归一化局部离群因子值(LOF_(nor))的全新监测数据异常度量化表达式。最后通过引入拉伊达准则,依据计算得到的异常分数,对异常值进行定性筛查。试验结果表明,相较于热门异常检测算法,在查全率层面提升18.32%以上;查准率提升20.14%以上;准确率提升0.71%以上。可针对大坝安全监测数据中的异常值进行有效检测。 展开更多
关键词 异常检测 孤立森林 局部离群因子 评价指标
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Biodiversity responses to insular fragmentation in Amazonia: Two decades of research in the Balbina Hydroelectric Reservoir 被引量:1
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作者 Ana Filipa Palmeirim Maíra Benchimol +4 位作者 Danielle Storck-Tonon Anderson S.Bueno Isabel L.Jones Gilmar Klein Carlos A.Peres 《Zoological Research(Diversity and Conservation)》 2024年第2期106-116,共11页
As hydropower development expands across lowland tropical forests,flooding and concomitant insular fragmentation have become important threats to biodiversity.Newly created insular landscapes serve as natural laborato... As hydropower development expands across lowland tropical forests,flooding and concomitant insular fragmentation have become important threats to biodiversity.Newly created insular landscapes serve as natural laboratories to investigate biodiversity responses to fragmentation.One of these most iconic landscapes is the Balbina Hydroelectric Reservoir in Brazilian Amazonia,occupying>400000 ha and comprising>3500 forest islands.Here,we synthesise the current knowledge on responses of a wide range of biological groups to insular fragmentation at Balbina.Sampling has largely concentrated on a set of 22 islands and three mainland sites.In total,39 studies were conducted over nearly two decades,covering 17 vertebrate,invertebrate,and plant taxa.Although species responses varied according to taxonomic group,island area was consistently included and played a pivotal role in 66.7%of all studies examining patterns of species diversity.Species persistence was further affected by species traits,mostly related to species capacity to use/traverse the aquatic matrix or tolerate habitat degradation,as noted for species of vertebrates and orchid bees.Further research is needed to improve our understanding of such effects on wider ecosystem functioning.Environmental Impact Assessments must account for changes in both the remaining habitat amount and configuration,and subsequent long-term species losses. 展开更多
关键词 Habitat loss Hydropower dams Landbridge local extinctions Species-area relationships Species diversity Tropical forests
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基于局部线性嵌入和深度森林算法的电力客户投诉预测模型 被引量:1
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作者 张梅 保富 《电测与仪表》 北大核心 2024年第1期107-112,共6页
由于电力市场竞争日益激烈,用户对服务质量的要求不断提高,用户投诉量持续上升。在基于大数据的电力客户投诉预测模型的体系结构基础上,提出一种基于局部线性嵌入和深度森林算法的电力客户投诉预测方法。采用局部线性嵌入算法对客户投... 由于电力市场竞争日益激烈,用户对服务质量的要求不断提高,用户投诉量持续上升。在基于大数据的电力客户投诉预测模型的体系结构基础上,提出一种基于局部线性嵌入和深度森林算法的电力客户投诉预测方法。采用局部线性嵌入算法对客户投诉预测模型的输入特征向量进行降维处理,减少计算量和避免陷入局部最优解;对降维后的投诉预测特征向量进行多粒度扫描,提高其表征学习能力;基于级联森林建立深度森林算法模型,实现客户投诉预测。实际数据的仿真结果表明,与不进行降维处理及其他预测模型相比,文中所提出的预测模型可以更准确地预测客户投诉趋势,为电力企业客户投诉分析和预测提供了参考依据。 展开更多
关键词 电力客户 投诉预测模型 局部线性嵌入 深度森林算法
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基于IRF-PF算法的WLAN室内定位方法
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作者 柴海珑 王小鹏 龙良 《兰州交通大学学报》 CAS 2024年第1期44-50,82,共8页
针对室内复杂环境下无线局域网接收信号强度的时变波动性,提出一种基于改进随机森林算法并融合粒子滤波的室内定位方法。首先,通过自适应滑动窗口选取接收信号强度较为平滑的信号接入点作为定位指纹特征建立决策树,从而减少特征空间的噪... 针对室内复杂环境下无线局域网接收信号强度的时变波动性,提出一种基于改进随机森林算法并融合粒子滤波的室内定位方法。首先,通过自适应滑动窗口选取接收信号强度较为平滑的信号接入点作为定位指纹特征建立决策树,从而减少特征空间的噪声;然后,利用bagging抽样后的袋外数据赋予决策树不同的投票权重等级,增大决策树类别间判别差异性,优化随机森林算法在目标位置与接收信号强度间弱映射关联性场景下定位精度低的问题,依据改进的随机森林算法建立位置坐标与接收信号强度间的映射模型,计算定位点的位置;最后,为了提高定位准确性与稳定性,将依据改进随机森林算法计算出的位置作为粒子滤波的观测量,利用粒子滤波对目标位置进行估计和预测。在Zenodo数据集上的实验结果表明:提出的算法在定位误差2 m范围内精度达到75.8%,在4 m范围内精度已经高达94.8%;相比于传统随机森林算法,能够将2 m内的定位精度提高11.5%;与K近邻、岭回归和贝叶斯等室内定位算法相比,定位精度和算法实时性也得到明显提升。 展开更多
关键词 室内定位 随机森林 无线局域网 加权投票 粒子滤波
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Biodiversity of Edible Caterpillars of Imbrasia and Host Plants in Boukoko (Central African Republic)
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作者 Lucie Aba-Toumnou Solange-Patrica Wango +5 位作者 Denis Beina Jean-Pierre Moalbaye Gorgon Igor Touckia Rufin Reo-Ndouba Felix Allah-Barem Olga Diane Yongo 《Advances in Entomology》 2024年第1期38-55,共18页
In Central African Republic, edible caterpillars of Imbrasia gender are income of rural populations, present an opportunity to improve food security and belonging to the category of Non-wood forest products. The goal ... In Central African Republic, edible caterpillars of Imbrasia gender are income of rural populations, present an opportunity to improve food security and belonging to the category of Non-wood forest products. The goal of this study is to document the ecology of caterpillars of genre Imbrasia in relation to its host plants in Boukoko. The questionnaire was addressed to the actors of the collection and consumption of caterpillars in this Commune, to their local knowledge concerning this food resource as well as the plants of their locality on which caterpillars are collected. The survey took place in September to October 2022 and as a general rule, the 120 respondents were elderly people whose age range varied from 35 to 70 years old. Plant samples are collected in their natural environment. Based on local names;herbaria are mounted, plants photographed and samples collected. The types of edible caterpillars have been inventoried in the field in collaboration with the local populations who consume them. Based on local names, the caterpillars are captured manually from morphological traits and then stored in bottles containing 70% ethanol. The specimens were identified. The data was entered into the Excel spreadsheet which also made it possible to produce histograms with the frequencies of the plant species most valued by the different caterpillars. A Principal Component Analysis (PCA) was then performed using R software to highlight the correlation between caterpillars and host plants. The main economic importance trees hosting edible caterpillars of Imbrasia gender in Boukoko region are: Entandrophragma cylindricum, Pentaclethra macrophylla, Maesopsis eminii, Albizia ferruginea, Macaranga spinosa, Amphimas ferrugineus, Pentaclethra macrophylla, Racosperma auriculiforme, Eribroma oblonga. The Principal Component Analysis (PCA) carried out to assess the variability between the different species of caterpillars according to their host plants shows that the first two axes F1 and F2 explain 27.34% of the overall variability. The different variables along the two factorial axes are weakly correlated. The caterpillar species Imbrasia truncata, Imbrasia epimethea, Imbrasia obscura, Imbrasia petiveri, Imbrasia forda and Imbrasia alopia have more host plant diversity than the caterpillar species: Imbrasia melanops, Imbrasia eblis, Imbrasia anthina, Imbrasia wahlbergii and Imbrasia oyemensis. 展开更多
关键词 forest Degradation Losing Biodiversity of Consumed Insects local Population
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“双一流”视域下地方农林高校一流学科建设的机遇与策略
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作者 孙海涛 隋成竹 《青岛农业大学学报(社会科学版)》 2024年第2期116-119,125,共5页
地方农林高校是我国高等教育的重要组成部分,致力于为实现农业农村现代化和解决“三农”问题提供智力保障,但是其学科建设存在高水平学科和高层次人才数量少、高水平科研成果少、社会服务水平低等问题。“双一流”建设以解决以往重点建... 地方农林高校是我国高等教育的重要组成部分,致力于为实现农业农村现代化和解决“三农”问题提供智力保障,但是其学科建设存在高水平学科和高层次人才数量少、高水平科研成果少、社会服务水平低等问题。“双一流”建设以解决以往重点建设工程中产生的问题为导向,坚持在竞争中扶优扶强扶特,为地方农林高校学科建设的特色发展提供了机遇和保障。地方农林高校应充分抓住“双一流”建设提供的机遇,坚持农林特色和差异化发展,坚持开放办学,完善内部治理体系,努力建成优势突出、特色鲜明的一流农林学科。 展开更多
关键词 双一流 地方农林高校 学科建设
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RFS-RF的局部非线性模型辨识新方法
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作者 姜洋 马砚秋 +2 位作者 陈榕 刘景良 张羲岭 《武夷学院学报》 2024年第6期63-69,共7页
鉴于恢复力曲面法(Restoring Force Surface,RFS)和随机森林(Random Forest,RF)模型在参数辨识领域的优越性,结合上述两种方法提出一种新的基于RFS-RF的局部非线性模型辨识方法。首先,针对局部非线性模型求解其动力响应。其次,根据获得... 鉴于恢复力曲面法(Restoring Force Surface,RFS)和随机森林(Random Forest,RF)模型在参数辨识领域的优越性,结合上述两种方法提出一种新的基于RFS-RF的局部非线性模型辨识方法。首先,针对局部非线性模型求解其动力响应。其次,根据获得的动力响应计算恢复力曲面与边际谱,然后再通过边际谱求解非线性指标。再次,通过多次改变结构的刚度和阻尼参数生成若干组非线性指标并建立随机森林模型。然后,将新的非线性指标作为预测集输入已经建立的随机森林模型并判断系统的非线性类型和非线性函数形式。最后,采用最小二乘法对局部非线性系统的待求参数进行精确识别。通过一个四层剪切型框架结构模型对所提方法进行验证,研究结果表明:基于RFS-RF的多自由度局部非线性模型辨识方法能够准确识别结构系统的非线性类型、函数形式以及未知参数。 展开更多
关键词 恢复力曲面 随机森林 边际谱 模型辨识 局部非线性
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