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Can Digital Intelligence and Cyber-Physical-Social Systems Achieve Global Food Security and Sustainability? 被引量:1
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作者 Yanfen wang Mengzhen Kang +7 位作者 Yali Liu Juanjuan Li Kai Xue xiujuan wang Jianqing Du Yonglin Tian Qinghua Ni Fei-Yue wang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第11期2070-2080,共11页
Plants sequester carbon through photosynthesis and provide primary productivity for the ecosystem. However, they also simultaneously consume water through transpiration, leading to a carbon-water balance relationship.... Plants sequester carbon through photosynthesis and provide primary productivity for the ecosystem. However, they also simultaneously consume water through transpiration, leading to a carbon-water balance relationship. Agricultural production can be regarded as a form of carbon sequestration behavior.From the perspective of the natural-social-economic complex ecosystem, excessive water usage in food production will aggravate regional water pressure for both domestic and industrial purposes. Hence, achieving a harmonious equilibrium between carbon and water resources during the food production process is a key scientific challenge for ensuring food security and sustainability. Digital intelligence(DI) and cyber-physical-social systems(CPSS) are emerging as the new research paradigms that are causing a substantial shift in the conventional thinking and methodologies across various scientific fields, including ecological science and sustainability studies. This paper outlines our recent efforts in using advanced technologies such as big data, artificial intelligence(AI), digital twins, metaverses, and parallel intelligence to model, analyze, and manage the intricate dynamics and equilibrium among plants, carbon, and water in arid and semiarid ecosystems. It introduces the concept of the carbon-water balance and explores its management at three levels: the individual plant level, the community level, and the natural-social-economic complex ecosystem level. Additionally, we elucidate the significance of agricultural foundation models as fundamental technologies within this context. A case analysis of water usage shows that, given the limited availability of water resources in the context of the carbon-water balance, regional collaboration and optimized allocation have the potential to enhance the utilization efficiency of water resources in the river basin. A suggested approach is to consider the river basin as a unified entity and coordinate the relationship between the upstream, midstream and downstream areas. Furthermore, establishing mechanisms for water resource transfer and trade among different industries can be instrumental in maximizing the benefits derived from water resources.Finally, we envisage a future of agriculture characterized by the integration of digital, robotic and biological farming techniques.This vision aims to incorporate small tasks, big models, and deep intelligence into the regular ecological practices of intelligent agriculture. 展开更多
关键词 Carbon-water balance DECISION-SUPPORT digital intelligence(DI) foundation models PLANNING
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Origin of submarine canyon-channel systems along the middle segment of West Mariana Ridge,Philippine Sea
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作者 Guangxu ZHANG Shuang LI +4 位作者 Wei LI xiujuan wang Duanxin CHEN Dongdong DONG Wenlong wang 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2023年第3期881-896,共16页
Submarine canyon-channel systems have been documented in the Parece Vela Basin,West Mariana Ridge;however,the mechanism of the formation and controlling factors remain poorly understood.Based on high-resolution multib... Submarine canyon-channel systems have been documented in the Parece Vela Basin,West Mariana Ridge;however,the mechanism of the formation and controlling factors remain poorly understood.Based on high-resolution multibeam bathymetric data and two-dimensional(2D)seismic profiles,we identified and mapped the submarine canyon-channel system along the middle segment of West Mariana Ridge in the Philippine Sea.These submarine canyon-channels show a main W-E orientation at depth of 2000–4500 m.They are approximately 72–128 km in length and 1.3–15 km in width,and their canyon heads are adjacent to the seamounts with several branches.The upper reaches of submarine canyon-channels are characterized by deeply incised,narrow,V-shaped thalwegs,suggesting the powerful erosion of gravity flows.The distinguished sediment waves are suggested to be resulted from the interaction of turbidity currents and seafloor.Our observations demonstrate that gravity flows originated from the collapses of seamount flanks plays a vital role in developing the submarine canyonchannel system along the West Mariana Ridge.This work provides better understanding of erosion,transport,and deposition of sediments from subducting ridges to deep-water basins,and also new insights into the origin and evolution of submarine canyon-channel systems along subducting ridges. 展开更多
关键词 submarine canyon-channel system gravity flow subducting ridges West Mariana Ridge
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Physical characteristics of high concentrated gas hydrate reservoir in the Shenhu production test area,South China Sea
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作者 Jiapeng JIN xiujuan wang +7 位作者 Zhenyu ZHU Pibo SU Lixia LI Qingping LI Yiqun GUO Jin QIAN Zhendong LUAN Jilin ZHOU 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2023年第2期694-709,共16页
High concentrated and heterogeneous distribution of gas hydrates have been identified in the gas hydrate production test region in the Shenhu area,South China Sea.The gas hydrate-bearing sediments with high saturation... High concentrated and heterogeneous distribution of gas hydrates have been identified in the gas hydrate production test region in the Shenhu area,South China Sea.The gas hydrate-bearing sediments with high saturation locate at two ridges of submarine canyon with different thickness and saturations just above the bottom simulating reflection.The crossplots of gamma ray,acoustic impedance(P-impedance)and porosity at four sites show that the sediments can be divided into the upper and lower layers at different depths,indicating different geotechnical reservoir properties.Therefore,the depositional environments and physical properties at two ridges are analyzed and compared to show the different characteristics of hydrate reservoir.High porosity,high P-wave velocity,and coarse grain size indicate better reservoir quality and higher energy depositional environment for gas hydrate at Sites W18 and W19 than those at Sites W11 and W17.Our interpretation is that the base of canyon deposits at Sites W18 and W19 characterized by upward-coarsening units may be turbidity sand layers,thus significantly improving the reservoir quality with increasing gas hydrate saturation.The shelf and slope sliding deposits compose of the fine-grained sediments at Sites W11 and W17.The gas hydrate production test sites were conducted at the ridge of W11 and W17,mainly because of the thicker and larger area of gas hydrate-bearing reservoirs than those at Sites W18 and W19.All the results provide useful insights for assessing reservoir quality in the Shenhu area. 展开更多
关键词 reservoir properties gas hydrate production test region depositional environment South China Sea
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C2Net-YOLOv5: A Bidirectional Res2Net-Based Traffic Sign Detection Algorithm
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作者 xiujuan wang Yiqi Tian +1 位作者 Kangfeng Zheng Chutong Liu 《Computers, Materials & Continua》 SCIE EI 2023年第11期1949-1965,共17页
Rapid advancement of intelligent transportation systems(ITS)and autonomous driving(AD)have shown the importance of accurate and efficient detection of traffic signs.However,certain drawbacks,such as balancing accuracy... Rapid advancement of intelligent transportation systems(ITS)and autonomous driving(AD)have shown the importance of accurate and efficient detection of traffic signs.However,certain drawbacks,such as balancing accuracy and real-time performance,hinder the deployment of traffic sign detection algorithms in ITS and AD domains.In this study,a novel traffic sign detection algorithm was proposed based on the bidirectional Res2Net architecture to achieve an improved balance between accuracy and speed.An enhanced backbone network module,called C2Net,which uses an upgraded bidirectional Res2Net,was introduced to mitigate information loss in the feature extraction process and to achieve information complementarity.Furthermore,a squeeze-and-excitation attention mechanism was incorporated within the channel attention of the architecture to perform channel-level feature correction on the input feature map,which effectively retains valuable features while removing non-essential features.A series of ablation experiments were conducted to validate the efficacy of the proposed methodology.The performance was evaluated using two distinct datasets:the Tsinghua-Tencent 100K and the CSUST Chinese traffic sign detection benchmark 2021.On the TT100K dataset,the method achieves precision,recall,and Map0.5 scores of 83.3%,79.3%,and 84.2%,respectively.Similarly,on the CCTSDB 2021 dataset,the method achieves precision,recall,and Map0.5 scores of 91.49%,73.79%,and 81.03%,respectively.Experimental results revealed that the proposed method had superior performance compared to conventional models,which includes the faster region-based convolutional neural network,single shot multibox detector,and you only look once version 5. 展开更多
关键词 Target detection traffic sign detection autonomous driving YOLOv5
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Social Engineering Attack-Defense Strategies Based on Reinforcement Learning
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作者 Rundong Yang Kangfeng Zheng +2 位作者 xiujuan wang Bin Wu Chunhua Wu 《Computer Systems Science & Engineering》 SCIE EI 2023年第11期2153-2170,共18页
Social engineering attacks are considered one of the most hazardous cyberattacks in cybersecurity,as human vulnerabilities are often the weakest link in the entire network.Such vulnerabilities are becoming increasingl... Social engineering attacks are considered one of the most hazardous cyberattacks in cybersecurity,as human vulnerabilities are often the weakest link in the entire network.Such vulnerabilities are becoming increasingly susceptible to network security risks.Addressing the social engineering attack defense problem has been the focus of many studies.However,two main challenges hinder its successful resolution.Firstly,the vulnerabilities in social engineering attacks are unique due to multistage attacks,leading to incorrect social engineering defense strategies.Secondly,social engineering attacks are real-time,and the defense strategy algorithms based on gaming or reinforcement learning are too complex to make rapid decisions.This paper proposes a multiattribute quantitative incentive method based on human vulnerability and an improved Q-learning(IQL)reinforcement learning method on human vulnerability attributes.The proposed algorithm aims to address the two main challenges in social engineering attack defense by using a multiattribute incentive method based on human vulnerability to determine the optimal defense strategy.Furthermore,the IQL reinforcement learning method facilitates rapid decision-making during real-time attacks.The experimental results demonstrate that the proposed algorithm outperforms the traditional Qlearning(QL)and deep Q-network(DQN)approaches in terms of time efficiency,taking 9.1%and 19.4%less time,respectively.Moreover,the proposed algorithm effectively addresses the non-uniformity of vulnerabilities in social engineering attacks and provides a reliable defense strategy based on human vulnerability attributes.This study contributes to advancing social engineering attack defense by introducing an effective and efficient method for addressing the vulnerabilities of human factors in the cybersecurity domain. 展开更多
关键词 Social engineering game theory reinforcement learning Q-LEARNING
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Rural Domestic Sewage Treatment Model: Case Study Based on Dongying Section of the Yellow River Basin
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作者 Shan Zhang Yu wang xiujuan wang 《Journal of Environmental Protection》 CAS 2023年第3期172-184,共13页
The 20<sup>th</sup> National Congress of the Communist Party of China proposed to promote the improvement of urban and rural living environment and build livable and workable villages and beautiful village... The 20<sup>th</sup> National Congress of the Communist Party of China proposed to promote the improvement of urban and rural living environment and build livable and workable villages and beautiful villages. The development and challenges of rural domestic sewage treatment coexist. Based on the field investigation of 15 administrative villages in 3 districts and counties of Dongying City, there is a big gap between the development status of rural domestic sewage treatment and expectations. Investigate rural domestic sewage treatment cases in-depth, and condense four modes of primitive, developmental, mature and advanced in a variety of different rural domestic sewage treatment models for discussion, among which, the village sewage treatment work under the mature mode has achieved remarkable results, and is at the forefront of the current rural domestic sewage treatment. Through the multi-case analysis method, the practical dilemma of sewage treatment in different models of villages is summarized, and the feasible improvement path is explored, which contributes to the ecological protection and high-quality development of Dongying and the Yellow River Basin. 展开更多
关键词 Rural Domestic Sewage Human Settlements Ecological Protection and High-Quality Development of the Yellow River Basin
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Solving the Urban Domestic Waste Classification Dilemma from a Coalitional Game Perspective
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作者 Yuhan Li Xuanqi Liu xiujuan wang 《Journal of Environmental Protection》 CAS 2023年第4期243-253,共11页
The effective classification of urban domestic waste is the key to achieve a “waste-free city” and provides an essential guarantee for resource utilization. This article takes a coalitional game perspective to study... The effective classification of urban domestic waste is the key to achieve a “waste-free city” and provides an essential guarantee for resource utilization. This article takes a coalitional game perspective to study the dilemmas in urban domestic waste separation from the cooperative interaction of residents, government, and enterprises. The study finds that urban domestic waste classification in China is currently facing many problems, focusing on: 1) insufficient consensus among residents, 2) shortage of input funds, 3) corporate profitability difficulties, 4) weak policy constraints, and 5) difficulties in integrating goals. In this regard, each participating body still needs to focus on collective interests, coalitional games, break the dilemma society, and promote the long-term management of urban domestic waste. 展开更多
关键词 Waste Classification Coalitional Game Multiple Subjects
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The Fulfillment of Government Responsibilities in the Collaborative Governance of Rural Water Pollution
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作者 Xuanqi Liu Yuhan Li xiujuan wang 《Open Journal of Applied Sciences》 CAS 2023年第4期496-507,共12页
Rural environmental pollution is becoming more and more serious, which has become an important problem to be solved urgently in our country under the background of the new era. Protecting the ecological environment is... Rural environmental pollution is becoming more and more serious, which has become an important problem to be solved urgently in our country under the background of the new era. Protecting the ecological environment is one of the important functions of the government, and protecting the rural water environment is the unshirkable responsibility of the local governments. As the main body of rural water pollution control, how to define and fulfill the local governments’ responsibilities is of great significance to the advancement of the overall governance work. This paper starts from the local governments, which are the important main body of rural environmental governance. By comparing the similarities and differences between the performance of government responsibilities under the traditional governance model and the collaborative governance model, clarifies the governance responsibilities of the local governments. And further explores the effective measures for the government to play the main role, fulfill the main responsibilities, and participate in the collaborative governance of rural water pollution. 展开更多
关键词 Fulfillment of Government Responsibilities Rural Water Pollution Collaborative Governance
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Analysis on Residents’ Satisfaction and Its Influencing Factors with Water Environment Management: Based on the Data from Xiaoqing River
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作者 Lingshan Zhou Yu wang xiujuan wang 《Open Journal of Modern Hydrology》 CAS 2023年第2期129-140,共12页
Xiaoqing River is one of the key rivers in the Yellow River Basin, and its management satisfaction is the content that the government should consider when formulating policies. This paper concentrates on residents’ s... Xiaoqing River is one of the key rivers in the Yellow River Basin, and its management satisfaction is the content that the government should consider when formulating policies. This paper concentrates on residents’ satisfaction of water environment management in Jinan section of Xiaoqing River, using questionnaires to find out the problems and effects of Xiaoqing River management. Based on the correlation analysis of the questionnaire data, the results show that five factors including the impact of water pollution, understanding of Xiaoqing River governance, willingness to participate in Xiaoqing River governance, policy publicity, and government regulation have a positive impact on the satisfaction of Xiaoqing River water environment governance. Finally, the paper puts forward some countermeasures and suggestions to increase residents’ satisfaction from five aspects, such as increasing publicity efforts, paying attention to the cultivation of public participation consciousness, etc. 展开更多
关键词 Water Environment Management Satisfaction Survey Correlation Analysis
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Research Progress Related to Rural Domestic Sewage Treatment
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作者 Yu wang xiujuan wang 《Agricultural Sciences》 2023年第6期775-784,共10页
Rural domestic sewage treatment is an important part of the rural revitalization strategy and a key action to build a livable, livable and beautiful countryside. This paper composes and summarizes the relevant studies... Rural domestic sewage treatment is an important part of the rural revitalization strategy and a key action to build a livable, livable and beautiful countryside. This paper composes and summarizes the relevant studies on rural domestic sewage treatment from the governance techniques and modes of governance subjects and research perspectives, in order to provide reference for the implementation of rural revitalization strategy and rural domestic sewage treatment research and action implementation. 展开更多
关键词 COUNTRYSIDE Domestic Sewage Sewage Treatment
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Research on the Development of Rural Family Farm: A Case Study of Shandong Province in China 被引量:2
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作者 xiujuan wang Jilian Hu 《Agricultural Sciences》 2016年第4期196-205,共10页
In recent years, the rural family farms in Shandong Province of China have been developing very fast. They have achieved remarkable economic effects on improving the technical and equipment level of agricultural produ... In recent years, the rural family farms in Shandong Province of China have been developing very fast. They have achieved remarkable economic effects on improving the technical and equipment level of agricultural production, farmers’ professional quality, the efficiency of land production and farmers’ income-increase, etc. However, there also exist the problems of non-smooth land transfer, unclear farm recognition-standard, more difficult loan-financing, imperfect social service and so on. This paper suggests that measures should be taken to deepen the reform of the rural land system, perfect the land transfer mechanism, clarify the family farms confirmed standards, improve the family farms and financing system, perfect the socialized service system, and thus create a relaxed environment and conditions for the development of family farms in order to promote its healthy development. 展开更多
关键词 Rural Family Farm Rural Land Transfer Farms’ Social Service Agricultural Development
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The Architectural Unit Setting up and Architectural Characteristics of Néré, <i>Parkia biglobosa</i>, Jack, R. Br. (Fabaceae)
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作者 Beda Innocent Adji Doffou Sélastique Akaffou +9 位作者 Véronique Letort Mengzhen Kang xiujuan wang Marc Jaeger Philippe De Reffye Kouadio Henri Kouassi Yao Patrice Houphouet Jerôme Duminil Yves Caraglio Sylvie Sabatier 《American Journal of Plant Sciences》 2022年第1期109-136,共28页
<i><span style="font-family:;" "="">Parkia biglobosa</span></i><span style="font-family:;" "=""> is a much-loved and over-exploited Afric... <i><span style="font-family:;" "="">Parkia biglobosa</span></i><span style="font-family:;" "=""> is a much-loved and over-exploited African savannah species for its socio-economic importance. Knowing and taking into account its architectural unit, which is the basis for diagnosing phenology, productivity and tree health, could provide a new perspective on its sustainable management. The aim of this study is to establish the architectural development in <i>Parkia biglobosa</i> by retrospective analysis. To achieve this objective, 390 individuals of all sizes ranging from seedlings to senescent trees were observed and analysed under various soil and climatic conditions in Côte d’Ivoire. The results showed that <i>Parkia biglobosa</i> is a light plant but shading tolerant. It is a mixed vegetative axis plant, the stem is orthotropic* in its proximal part and plagiotropic* (collapsing) in its distal part in young stage. The tree then transitions to an adult and old stage into a tree with a plagiotropic* axis in the proximal and distal parts, the trunk is built up by superimposing collapsed relay axes that gradually straighten, branching is sympodial*, growth is defined and sexuality is terminal and lateral. The ontogeny takes place in three phases: initiation of development and establishment of the crown (young), then flowering and establishment of the architectural unity (adult) and finally the death of secondary axes in the crown, duplication of the architecture by a series of partial and total reiterations (old). The level of organisation is 5: the phytomere, the module or growth unit, the axis, the architectural unit and the reiterated complex. Retrospective analysis of the modules showed that the dimensions of the growth units are indicators of morphological variation and species adaptation to a changing climate (<i>P</i> < 0.05). However, the equations generated by the morphological and habitat dimension linkage models are not significant (<i>R</i><sup>2</sup> and <i>r</i> </span><span style="font-family:;" "="">< 0.7) to be used as a guide for field data collection. This study represents an initiation into the architectural study of this species and the information provided will serve as a basis for further research into the architecture in relation to the sustainable use of this species.</span> 展开更多
关键词 Parkia biglobosa Architectural Development Architectural Unit Côte d’Ivoire
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A Review on Water-Saving Agriculture in Europe
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作者 Shan Zhang xiujuan wang Lingshan Zhou 《Journal of Water Resource and Protection》 2022年第4期305-317,共13页
This paper aims to analyze the research on the current situation of water-saving agriculture development in Europe. Water-saving agriculture in Europe started early, governments and farmers in various countries have a... This paper aims to analyze the research on the current situation of water-saving agriculture development in Europe. Water-saving agriculture in Europe started early, governments and farmers in various countries have a strong awareness of water-saving in agriculture and have achieved certain results. Due to the global spread of the COVID-19 pandemic, the lack of up-to-date field research, the complexity of various agricultural disciplines and categories, and the lack of information sharing, the current cognition of recent progress in the development of water-saving agriculture in Europe is not comprehensive enough. This paper selects four representative European countries: Spain, Germany, Italy, and Denmark as the research objects. Based on the existing research of Chinese and Western scholars, this paper analyzes and studies the current situation of water-saving agriculture in Europe. It has far-reaching significance for other countries in the world to have further development in water-saving agriculture and to protect water resources. 展开更多
关键词 European Agricultural Water Water-Saving Agriculture Water Resources
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A Review on Development Water-Saving Agriculture in Asia
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作者 Lingshan Zhou xiujuan wang Shan Zhang 《Agricultural Sciences》 2022年第4期491-499,共9页
The development of water-saving agriculture is of great significance not only for increasing farmers’ production and income, but also for protecting water resources. The purpose of this paper is to learn from the exp... The development of water-saving agriculture is of great significance not only for increasing farmers’ production and income, but also for protecting water resources. The purpose of this paper is to learn from the experience of Israel, Japan, Korea and Singapore, improve the low efficiency of agricultural water use in China, and solve the problem of water shortage, promote the development of agriculture. This article concludes that the experience of water-saving agriculture in Israel is advanced irrigation technology, sound laws and regulations, and emphasis on science and technology. Japan’s water-saving agriculture is characterized by an efficient irrigation program and a strict agricultural water management policy. Korea’s experience in water-saving agriculture is that it has a strict water management system, with the government subsidizing the cost of irrigation projects and integrating water into agricultural development planning. Singapore’s experience in water-saving agriculture is to raise awareness of water conservation and to use step water prices. In order to promote the sustainable development of water-saving agriculture in China, the research on water-saving agriculture in the future can be carried out from the aspects of agricultural production or related agricultural technology. 展开更多
关键词 Asian Water Saving Water Saving Agriculture Development Experience Water Resources Management
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Intrusion Detection Algorithm Based on Density,Cluster Centers,and Nearest Neighbors 被引量:5
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作者 xiujuan wang Chenxi Zhang Kangfeng Zheng 《China Communications》 SCIE CSCD 2016年第7期24-31,共8页
Intrusion detection aims to detect intrusion behavior and serves as a complement to firewalls.It can detect attack types of malicious network communications and computer usage that cannot be detected by idiomatic fire... Intrusion detection aims to detect intrusion behavior and serves as a complement to firewalls.It can detect attack types of malicious network communications and computer usage that cannot be detected by idiomatic firewalls.Many intrusion detection methods are processed through machine learning.Previous literature has shown that the performance of an intrusion detection method based on hybrid learning or integration approach is superior to that of single learning technology.However,almost no studies focus on how additional representative and concise features can be extracted to process effective intrusion detection among massive and complicated data.In this paper,a new hybrid learning method is proposed on the basis of features such as density,cluster centers,and nearest neighbors(DCNN).In this algorithm,data is represented by the local density of each sample point and the sum of distances from each sample point to cluster centers and to its nearest neighbor.k-NN classifier is adopted to classify the new feature vectors.Our experiment shows that DCNN,which combines K-means,clustering-based density,and k-NN classifier,is effective in intrusion detection. 展开更多
关键词 聚类中心 基于密度 入侵行为 测算法 入侵检测方法 最近邻 混合学习 分类器
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DeCASA in AgriVerse: Parallel Agriculture for Smart Villages in Metaverses 被引量:4
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作者 xiujuan wang Mengzhen Kang +2 位作者 Hequan Sun Philippe de Reffye Fei-Yue wang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2022年第12期2055-2062,共8页
The demand for food is tremendously increasing with the growth of the world population,which necessitates the development of sustainable agriculture under the impact of various factors,such as climate change.To fulfil... The demand for food is tremendously increasing with the growth of the world population,which necessitates the development of sustainable agriculture under the impact of various factors,such as climate change.To fulfill this challenge,we are developing Metaverses for agriculture,referred to as Agri Verse,under our Decentralized Complex Adaptive Systems in Agriculture(De CASA)project,which is a digital world of smart villages created alongside the development of Decentralized Sciences(De Sci)and Decentralized Autonomous Organizations(DAO)for Cyber-Physical-Social Systems(CPSSs).Additionally,we provide the architectures,operating modes and major applications of De CASA in AgriVerse.For achieving sustainable agriculture,a foundation model based on ACP theory and federated intelligence is envisaged.Finally,we discuss the challenges and opportunities. 展开更多
关键词 Parallel Agriculture Management and Control AgriVerse Agriculture CPSS ACP DAO-Based Platform Precision Agriculture
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Migrated hybrid turbidite-contourite channel-lobe complex of the late Eocene Rovuma Basin, East Africa 被引量:3
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作者 Yintao Lu Xiwu Luan +7 位作者 Boqing Shi Weimin Ran Fuliang Lü xiujuan wang Quanbin Cao Xiaoyong Xu Hui Sun Genshun Yao 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2021年第2期81-94,共14页
Analysis of 3 D seismic data and well log data from the Rovuma Basin in East Africa reveals the presence of a late Eocene channel-lobe complex on its slope.The first two channels,denoted as channel-1 and channel-2,are... Analysis of 3 D seismic data and well log data from the Rovuma Basin in East Africa reveals the presence of a late Eocene channel-lobe complex on its slope.The first two channels,denoted as channel-1 and channel-2,are initiated within a topographic low on the slope but come to a premature end when they are blocked by a topographic high in the northwest region of the basin.New channels migrate southeastward from channel-1 to channel-6 due to the region’s sufficient sediment supply and stripping caused by bottom currents.The primary factors controlling the development of the channel complex include its initial paleo-topographic of seafloor,the property of gravity flows,the direction of the bottom current,and the stacking and expansion of its levees.The transition zone from channel to lobe can also be clearly identified from seismic sections by its pond-shaped structure.At a certain point,thest systems record a transiton from erosive features to sedimentary features,and record a transition from a confined environment to an open environment.Channels and lobes can be differentiated by their morphologies:thick slump-debris flows are partly developed under channel sand sheets,whereas these slump-debris flows are not very well developed in lobes.Well log responses also record different characteristics between channels and lobes.The interpreted shale volume throughout the main channel records a box-shaped curve,thereby implying that confined channel complexes record high energy currents and abundant sand supply,whereas the interpreted shale volume throughout the lobe records an upward-fining shape curve,thereby indicating the presence of a reduced-energy current in a relatively open environment.Within the Rovuma Basin of East Africa,the average width of the Rovuma shelf is less than 10 km,the width of the slope is only approximately 40 km,and the slope gradient is 2°–4°.Due to this steep slope gradient,the sand-rich top sheet within the channel also likely contributes to the straight feature of the channel system.It is currently unclear whether the bottom current has any effect on its sinuosity. 展开更多
关键词 East Africa Rovuma Basin deep-water sediment channel-lobe complex
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Floret-specific differences in gene expression and support for the hypothesis that tapetal degeneration of Zea mays L. occurs via programmed cell death 被引量:2
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作者 David S. Skibbe xiujuan wang +3 位作者 Lisa A. Borsuk Daniel A. Ashlock Dan Nettleton Patrick S. Schnable 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2008年第10期603-616,共14页
The maize (Zea mays) spikelet consists of two florets, each of which contains three developmentally synchronized anthers. Morpho-logically, the anthers in the upper and lower florets proceed through apparently similar... The maize (Zea mays) spikelet consists of two florets, each of which contains three developmentally synchronized anthers. Morpho-logically, the anthers in the upper and lower florets proceed through apparently similar developmental programs. To test for global differences in gene expression and to identify genes that are coordinately regulated during maize anther development, RNA samples isolated from upper and lower floret anthers at six developmental stages were hybridized to cDNA microarrays. Approximately 9% of the tested genes exhibited statistically significant differences in expression between anthers in the upper and lower florets. This finding indicates that several basic biological processes are differentially regulated between upper and lower floret anthers, including metabolism, protein synthesis and signal transduction. Genes that are coordinately regulated across anther development were identified via cluster analysis. Analysis of these results identified stagespecific, early in development, late in development and biphasic expression profiles. Quantita-tive RT-PCR analysis revealed that four genes whose homologs in other plant species are involved in programmed cell death are upregulated just prior to the time the tapetum begins to visibly degenerate (i.e., the mid-microspore stage). This finding supports the hypothesis that developmentally normal tapetal degeneration occurs via programmed cell death. 展开更多
关键词 基因表达 细胞 小穗 玉米
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Lithium bis(oxalate)borate crosslinked polymer electrolytes for high-performance lithium batteries 被引量:2
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作者 Xiao wang Jujie Sun +8 位作者 Changhao Feng xiujuan wang Minghan Xu Jingjiang Sun Ning Zhang Jun Ma Qingfu wang Chengzhong Zong Guanglei Cui 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第4期228-235,共8页
Solid electrolytes play a vital role in solid-state Li secondary batteries,which are promising high-energy storage devices for new-generation electric vehicles.Nevertheless,obtaining a suitable solid electrolyte by a ... Solid electrolytes play a vital role in solid-state Li secondary batteries,which are promising high-energy storage devices for new-generation electric vehicles.Nevertheless,obtaining a suitable solid electrolyte by a simple and residue-free preparation process,resulting in a stable interface between electrolyte and electrode,is still a great challenge for practical applications.Herein,we report a self-crosslinked polymer electrolyte(SCPE)for high-performance lithium batteries,prepared by a one-step method based on 3-methoxysilyl-terminated polypropylene glycol(SPPG,a liquid oligomer).It is worth noting that lithium bis(oxalate)borate(Li BOB)can react with SPPG to form a crosslinked structure via a curing reaction.This self-formed polymer electrolyte exhibits excellent properties,including high roomtemperature ionic conductivity(2.6×10^(-4) S cm^(-1)),wide electrochemical window(4.7 V),and high Li ion transference number(0.65).The excellent cycling stability(500 cycles,83%)further highlights the improved interfacial stability after the in situ formation of SCPE on the electrode surface.Moreover,this self-formation strategy enhances the safety of the battery under mechanical deformation.Therefore,the present self-crosslinked polymer electrolyte shows great potential for applications in high-performance lithium batteries. 展开更多
关键词 Self-formed Crosslinking structure Polymer electrolyte Lithium batteries
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Application of optimal harvesting decision model to the analysis of Chinese forestry economic policy 被引量:1
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作者 Xin Jiang xiujuan wang 《Chinese Journal of Population,Resources and Environment》 2013年第4期333-344,共12页
This paper firstly extends the single period forest optimal harvesting decision model to infinite periods,in order to indicate how to determine the optimal rotation period aimed at maximizing forest revenue in all dir... This paper firstly extends the single period forest optimal harvesting decision model to infinite periods,in order to indicate how to determine the optimal rotation period aimed at maximizing forest revenue in all directions when repeat planting and harvesting trees on the same plot of earth till infinite future.The study also analyzes the influence of discounted rates,timber price,harvesting costs,planting costs,and tax on the determination of optimal rotation period;and how the optimal rotation period will change when we introduce the factors of continuously rising timber price and ecological revenue.Secondly,the authors introduce the intergenerational equity principle into the above model to design a resource-exploiting mode which satisfies bom the dynamic efficiency principle and the intergenerational equity principle.Last but not least,the research applies the above model to the analysis of Chinese forestry economic policy and explains the economic theory of institutions such as Government Purchasing Ecological Forest,Tree Compensation,and Forestry Subsidization,which provides a necessary theoretical foundation for future application of these new institutions.Besides,in regard to mis theoretical framework,the authors analyze the necessity of the Natural Forest Protection and Grain for Green projects which are currently being implemented in China.We also point out the emphasis of work to insure the project sustainable and successful.Finally,the research discusses the enterprise's incentive to over-the-quota harvesting and the government's means of restricting such behavior,which highlights the fact mat improved supervision and higher penalties are helpful in restricting over-the-quota harvesting. 展开更多
关键词 optimal ROTATION period INTERGENERATIONAL EQUITY ecological forest PURCHASE tree compensation FORESTRY SUBSIDY
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