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Measuring the Complexity of Business Organization and Business Software Using Analytic Hierarchy Process (AHP)
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作者 Alen Jakupovie Mile Pavlie 《Computer Technology and Application》 2011年第9期736-747,共12页
The paper shows a proposition of metrics for measuring the complexity of the business organization and business software. The metrics is based on a subjective estimation of complexity of the elements from a part of th... The paper shows a proposition of metrics for measuring the complexity of the business organization and business software. The metrics is based on a subjective estimation of complexity of the elements from a part of the structure of business organization or business software in relation to other elements from the observed part. Estimation is performed based on the measuring scale for comparison of complexity of elements, and reaching a final conclusion on the complexity of elements in relation to other elements, through the Analytic Hierarchy Process (AHP). Defined in this manner, the metrics represents a unique metrics for measuring the complexity of elements of business organization and business software, which enables their comparison. The paper also presents a short overview of existing metrics for measuring the complexity of business organization and business software. 展开更多
关键词 Analytic hierarchy process (AHP) business organization business software COMPLEXITY metrics
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Research advances in enhanced coal seam gas extraction by controllable shock wave fracturing
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作者 Chaojun Fan Hao Sun +6 位作者 Sheng Li Lei Yang Bin Xiao Zhenhua Yang Mingkun Luo Xiaofeng Jiang Lijun Zhou 《International Journal of Coal Science & Technology》 EI CAS CSCD 2024年第3期1-31,共31页
With the continuous increase of mining in depth,the gas extraction faces the challenges of low permeability,great ground stress,high temperature and large gas pressure in coal seam.The controllable shock wave(CSW),as ... With the continuous increase of mining in depth,the gas extraction faces the challenges of low permeability,great ground stress,high temperature and large gas pressure in coal seam.The controllable shock wave(CSW),as a new method for enhancing permeability of coal seam to improve gas extraction,features in the advantages of high efficiency,eco-friendly,and low cost.In order to better utilize the CSW into gas extraction in coal mine,the mechanism and feasibility of CSW enhanced extraction need to be studied.In this paper,the basic principles,the experimental tests,the mathematical models,and the on-site tests of CSW fracturing coal seams are reviewed,thereby its future research directions are provided.Based on the different media between electrodes,the CSW can be divided into three categories:hydraulic effect,wire explosion and excitation of energetic materials by detonating wire.During the process of propagation and attenuation of the high-energy shock wave in coal,the shock wave and bubble pulsation work together to produce an enhanced permeability effect on the coal seam.The stronger the strength of the CSW is,the more cracks created in the coal is,and the greater the length,width and area of the cracks being.The repeated shock on the coal seam is conducive to the formation of complex network fracture system as well as the reduction of coal seam strength,but excessive shock frequency will also damage the coal structure,resulting in the limited effect of the enhanced gas extraction.Under the influence of ground stress,the crack propagation in coal seam will be restrained.The difference of horizontal principal stress has a significant impact on the shape,propagation direction and connectivity of the CSW induced cracks.The permeability enhancement effect of CSW is affected by the breakage degree of coal seam.The shock wave is absorbed by the broken coal,which may hinder the propagation of CSW,resulting in a poor effect of permeability enhancement.When arranging two adjacent boreholes for CSW permeability enhancement test,the spacing of boreholes should not be too close,which may lead to negative pressure mutual pulling in the early stage of drainage.At present,the accurate method for effectively predicting the CSW permeability enhanced range should be further investigated. 展开更多
关键词 Controllable shock wave Permeability enhancement Gas extraction Basic principle Experimental test Mathematical models On-site test
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Factors affecting farmers'choice to adopt risk management strategies:The application of multivariate and multinomial probit models
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作者 Jamal Shah Majed Alharthi 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第12期4250-4262,共13页
This study investigates the factors that impact farmers'adoption of risk management strategies(RMS)in Pakistan during times of uncertainty.The study examines farmers'adoption of RMS using both multinomial prob... This study investigates the factors that impact farmers'adoption of risk management strategies(RMS)in Pakistan during times of uncertainty.The study examines farmers'adoption of RMS using both multinomial probit(MNP)and multivariate probit(MVP).Data were collected from 382 farmers sampled from four districts in KhyberPakhtunkhwa(KP)province of Pakistan via a multistage sampling technique.This study utilizes the MNP model,considering the assumption of Independence of Irrelevant Alternatives(IIA)and incorporating correlated error terms.The objective is to understand farmers'behavior in risky situations and determine if there is heterogeneity.Results are compared with the MVP model to assess robustness and gain deeper understanding of farmers'decisionmaking processes.The research findings reveal that our results are robust,and farmers behave homogeneously in various RMS scenarios.Farmers adopt RMS individually or in combination to mitigate the adverse effects of natural calamities on their livelihood.The risk-averse farmers,who perceive weather-related risks as a threat,access credits and information,and have farms close to a river are more likely to adopt RMS,irrespective of the format of the strategies available.Moreover,the predicted probabilities and correlation of the RMS and RM categories have strengthened our model estimation.These findings provide insights into the behavior of farmers in adopting RMS which are helpful for policymakers and stakeholders in developing strategies to mitigate the impacts of natural calamities on farmers. 展开更多
关键词 multinomial probit model multivariate probit model risk management strategies risk-attitude risk perception
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Role Dynamic Allocation of Human-Robot Cooperation Based on Reinforcement Learning in an Installation of Curtain Wall
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作者 Zhiguang Liu Shilin Wang +2 位作者 Jian Zhao Jianhong Hao Fei Yu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第1期473-487,共15页
A real-time adaptive roles allocation method based on reinforcement learning is proposed to improve humanrobot cooperation performance for a curtain wall installation task.This method breaks the traditional idea that ... A real-time adaptive roles allocation method based on reinforcement learning is proposed to improve humanrobot cooperation performance for a curtain wall installation task.This method breaks the traditional idea that the robot is regarded as the follower or only adjusts the leader and the follower in cooperation.In this paper,a self-learning method is proposed which can dynamically adapt and continuously adjust the initiative weight of the robot according to the change of the task.Firstly,the physical human-robot cooperation model,including the role factor is built.Then,a reinforcement learningmodel that can adjust the role factor in real time is established,and a reward and actionmodel is designed.The role factor can be adjusted continuously according to the comprehensive performance of the human-robot interaction force and the robot’s Jerk during the repeated installation.Finally,the roles adjustment rule established above continuously improves the comprehensive performance.Experiments of the dynamic roles allocation and the effect of the performance weighting coefficient on the result have been verified.The results show that the proposed method can realize the role adaptation and achieve the dual optimization goal of reducing the sum of the cooperator force and the robot’s Jerk. 展开更多
关键词 Human-robot cooperation roles allocation reinforcement learning
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Promoted catalytic property of Cu/SSZ-13 by introducing a minority of Mn for NO removal from diesel engine exhaust
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作者 Runnong Yang Wuyuan Liu +6 位作者 Zhaoying Wang Ming Sun Guangying Fu Zihan Gao Wenjian Jiao Rui Li Lin Yu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第7期172-182,共11页
The Cu-exchanged SSZ-13 with the small-pore chabazite framework is considered as a highly efficient catalyst for selective catalytic reduction of NO with NH_(3)(NH_(3)-SCR).In order to further improve the catalytic pr... The Cu-exchanged SSZ-13 with the small-pore chabazite framework is considered as a highly efficient catalyst for selective catalytic reduction of NO with NH_(3)(NH_(3)-SCR).In order to further improve the catalytic property,a series of Mn ion-assisted Cu/SSZ-13 powder catalysts were prepared by co-exchange method and stepwise exchange method.It is found that the NH_(3)-SCR activity,N_(2) selectivity,hydrothermal stability and sulfur resistance of Cu/SSZ-13 are promoted by introducing a minority of Mn(0.15%to 0.23%(mass))through co-exchange method.Characterization results reveal that the Cu,Mn co-exchange enables the higher amounts of Cu^(2+)active sites,the abundant medium strong and strong acid,the optimized ratio of Lewis acid to Brønsted acid etc.,which are required for a good NH_(3)-SCR catalytic property over broad temperature range and under harsh working environment.Moreover,a monolithic catalyst was prepared by impregnating a cordierite ceramic support into the coating slurry containing the optimized CuMn/SSZ-13 powder.The diesel engine bench tests show that Cu,Mn co-exchange gives the monolith catalyst a better catalytic property than commercial catalysts.This work provides an important guidance for the rational design of secondary-ion-assisted zeolites applied in NH_(3)-SCR. 展开更多
关键词 MnCu/SSZ-13 Co-exchange ZEOLITE CATALYSIS Selective catalytic reduction
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Research on the path of effective management of participation in joint-venture railway companies by China railway group
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作者 Shaoni Zhou Zhitian Zhou Chenxia Kang 《Railway Sciences》 2024年第4期530-539,共10页
Purpose-Following the regional restructuring,the number of joint-venture railway companies in which the Group participates has significantly increased.This paper aims to explore the challenges faced by China Railway G... Purpose-Following the regional restructuring,the number of joint-venture railway companies in which the Group participates has significantly increased.This paper aims to explore the challenges faced by China Railway Group in managing participation in joint-venture railway companies.The study seeks to propose specific approaches to ensure the effective management of these companies,thereby maximizing the benefits of the regional restructuring and supporting the development of a strong transportation country and a modern infrastructure system.Design/methodology/approach-Based on the change in the shareholding relationship between China Railway Group and the joint-venture railway companies,and considering the current situation of the regional restructuring of these companies,as well as the insights from existing literature and typical case studies,this paper proposes some specific paths for effective management of joint-stock railway companies which China Railway Group participated in.Findings-The problems in participation management are the unclear dual leadership role of the party committee,the lack of discourse power,the lack of synergy between shareholders,the increasing risk of sustainable operation of the loss-making companies and the role of dispatched personnel is not fully played.Based on the theories,combined with the existing research and practical cases,the paper proposed specific approaches,such as perfecting top-level system design,maintaining the discourse power,carrying out differentiated management,arranging personnel rationally,arranging shareholders synergy,and innovating methods to provide references for China Railway Group’s subsequent management of joint venture railway companies.Originality/value-This paper contributes to the existing literature by providing a comprehensive analysis of the challenges faced by China Railway Group in managing participation in joint-venture railway companies following the regional restructuring.The study offers novel insights and practical recommendations for addressing these challenges.The findings can serve as valuable references for China Railway Group’s subsequent management of joint-venture railway companies which participated in,as well as for other stateowned enterprises facing similar challenges in managing their joint ventures. 展开更多
关键词 China railway group Joint venture railway companies Participated relationship Effective management
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Breeding and Seed Production Techniques of New Aromatic Danxiangyouzhenliang Rice Variety with Good Quality and High Yield
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作者 Riwei HUANG Qiujun LONG +3 位作者 Zishuai SHANG Rihui HUANG Chunliang LIAO Yuechao LUO 《Asian Agricultural Research》 2024年第8期38-41,46,共5页
Danxiangyouzhenliang rice is a high-quality rice variety derived from the hybrid breeding of Danxiang 12A and Xianghuixiangmiao R133.Its unique temperature-sensitive three-line characteristics endow it with significan... Danxiangyouzhenliang rice is a high-quality rice variety derived from the hybrid breeding of Danxiang 12A and Xianghuixiangmiao R133.Its unique temperature-sensitive three-line characteristics endow it with significant advantages of high and stable yield,and its rice fragrance is exquisite and its taste is delicate.Danxiangyouzhenliang rice showed good resistance to rice blast and bacterial blight.On June 10,2021,Danxiangyouzhenliang rice passed the Guangxi Crop Variety Approval(Guishendao 2021074).Danxiangyouzhenliang rice is suitable to be planted as early and late rice in southern,central and northern Guangxi.This study summarized the breeding process and high-yielding seed production techniques of Danxiangyouzhenliang rice,in order to provide useful reference for rice breeders and growers. 展开更多
关键词 Danxiangyouzhenliang RICE SEED production technology HIGH-QUALITY RICE Hybrid BREEDING TEMPERATURE-SENSITIVE three-line
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SPERA Hydrogen System^(TM)by LOHC-MCH Method for Massive Hydrogen Storage and Transportation
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作者 Yoshimi Okada Kaji Naohiro +4 位作者 Osamu Ikeda Kenichi Imagawa Hironori Kawai Masashi Nagai Yasuhiro Inoue 《Journal of Environmental Science and Engineering(A)》 CAS 2024年第2期50-60,共11页
Expanding the hydrogen energy utilization is essential for decarbonization,and the commercialization of hydrogen energy carrier systems that can“store”and“transport”hydrogen in a large scale is necessary.The organ... Expanding the hydrogen energy utilization is essential for decarbonization,and the commercialization of hydrogen energy carrier systems that can“store”and“transport”hydrogen in a large scale is necessary.The organic chemical hydride method incorporates hydrogen atoms into the molecular structure of a LOHC(Liquid Organic Hydrogen Carrier)to store and transport hydrogen in a liquid state under normal temperature and pressure,and is a highly safe method with low business risk.Chiyoda has been developing the technology since 2002,completed a pilot demonstration in 2014 and named it the SPERA Hydrogen^(TM) System,and successfully completed an international supply chain demonstration that transports hydrogen from Brunei to Japan in a large scale in 2020,moving to the commercialization stage.Currently,Chiyoda is conducting feasibility studies with a number of domestic and foreign companies with the aim of commercializing the system as soon as possible.In this paper,outline,features,development status and our efforts in commercialization of SPERA HydrogenTM System are introduced. 展开更多
关键词 HYDROGEN carrier LOHC METHYLCYCLOHEXANE MCH TOLUENE
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Partial transient-liquid-phase bonding of TiC cermet to stainless steel using impulse pressuring with Ti/Cu/Nb interlayer 被引量:1
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作者 黄利 盛光敏 +2 位作者 李佳 黄光杰 袁新建 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第5期1025-1032,共8页
Partial transient liquid phase (PTLP) bonding of TiC cermet to 06Cr19Ni10 stainless steel was carried out. Impulse pressuring was used to reduce the bonding time, and a Ti/Cu/Nb interlayer was employed to alleviate ... Partial transient liquid phase (PTLP) bonding of TiC cermet to 06Cr19Ni10 stainless steel was carried out. Impulse pressuring was used to reduce the bonding time, and a Ti/Cu/Nb interlayer was employed to alleviate the detrimental effect of interfacial reaction products on the bonding strength. Successful bonding was achieved at 885℃ under a pulsed pressure of 2-10 MPa within durations in the range of 2-8 min, which was notably shortened in comparison with conventional PTLP bonding. Microstructure characterization revealed the o- phase with a limit solubility of Nb, a sequence of Ti-Cu intermetallic phases and solid solutions of Ni and Cu in α+β Ti in the reaction zone. The maximum shear strength of 106.7 MPa was obtained when the joint was bonded for 5 rain, indicating that a robust metallurgical bonding was achieved. Upon shear loading, the joints fractured along the Ti-Cu intermetallics interface and spread to the interior of TiC cermet in a brittle cleavage manner. 展开更多
关键词 TiC cermet transient liquid phase impulse pressuring mechanical property fracture
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老年人性生活质量影响因素的范围综述 被引量:1
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作者 张凤佩 杨振 +1 位作者 李雪华 王爱平 《International Journal of Nursing Sciences》 CSCD 2023年第2期167-173,共7页
目的 老年人通常被认为是无性生活,但性生活对老年人仍然很重要.因此,本研究对老年人性生活的相关研究进行范围综述,以明确老年人性生活质量的影响因素,为提升老年人性生活质量的研究提供依据.方法 按照Arksey和O'Malley提出的范围... 目的 老年人通常被认为是无性生活,但性生活对老年人仍然很重要.因此,本研究对老年人性生活的相关研究进行范围综述,以明确老年人性生活质量的影响因素,为提升老年人性生活质量的研究提供依据.方法 按照Arksey和O'Malley提出的范围综述方法框架,在PubMed、Web of Science、CINAHL、PsycINFO、Cochrane Library和Scopus等数据库中检索于2012年1月至2022年4月发表的与老年人性生活质量相关的研究文献,仅纳入经过同行评审的中文或英文文献.由2名研究员独立进行文献的筛选、提取和分析.结果 共检索出7 374篇文章,共纳入13篇文献.老年人性生活质量的影响因素包括生理因素、社会文化因素、健康因素、夫妻关系、相关知识的缺乏.结论 老年人性生活质量的影响因素相互交叉、相互影响.医务人员可以为改善老年人性生活质量提供指导或建议. 展开更多
关键词 老年人 影响因素 性生活 范围综述
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Elimination mechanism of coal and gas outburst based on geo‑dynamic system with stress–damage–seepage interactions 被引量:1
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作者 Lingjin Xu Chaojun Fan +4 位作者 Mingkun Luo Sheng Li Jun Han Xiang Fu Bin Xiao 《International Journal of Coal Science & Technology》 EI CAS CSCD 2023年第4期47-61,共15页
Coal and gas outburst is a complex dynamic disaster during coal underground mining.Revealing the disaster mechanism is of great signifcance for accurate prediction and prevention of coal and gas outburst.The geo-dynam... Coal and gas outburst is a complex dynamic disaster during coal underground mining.Revealing the disaster mechanism is of great signifcance for accurate prediction and prevention of coal and gas outburst.The geo-dynamic system of coal and gas outburst is proposed.The framework of geo-dynamic system is composed of gassy coal mass,geological dynamic environment and mining disturbance.Equations of stress–damage–seepage interaction for gassy coal mass is constructed to resolve the outburst elimination process by gas extraction with boreholes through layer in foor roadway.The results show the occurrence of outburst is divided into the evolution process of gestation,formation,development and termination of geo-dynamic system.The scale range of outburst occurrence is determined,which provides a spatial basis for the prevention and control of outburst.The formation criterion and instability criterion of coal and gas outburst are established.The formation criterion F1 is defned as the scale of the geo-dynamic system,and the instability criterion F2 is defned as the scale of the outburst geo-body.According to the geo-dynamic system,the elimination mechanism of coal and gas outburst—‘unloading+depressurization’is established,and the gas extraction by boreholes through layer in foor roadway for outburst elimination is given.For the research case,when the gas extraction is 120 days,the gas pressure of the coal seam is reduced to below 0.4 MPa,and the outburst danger is eliminated efectively. 展开更多
关键词 Coal and gas outburst Geo-dynamic system Stress–damage–seepage coupling Elimination mechanism Instability criterion Gas extraction
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An Efficient and Secure Aggregation Encryption Scheme in Edge Computing 被引量:1
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作者 Junhua Wu Xiaofei Sheng +2 位作者 Guangshun Li Kan Yu Junke Liu 《China Communications》 SCIE CSCD 2022年第3期245-257,共13页
Edge computing is a highly virtualized paradigm that can services the Internet of Things(Io T)devices more efficiently.It is a non-trivial extension of cloud computing,which can not only meet the big data processing r... Edge computing is a highly virtualized paradigm that can services the Internet of Things(Io T)devices more efficiently.It is a non-trivial extension of cloud computing,which can not only meet the big data processing requirements of cloud computing,but also collect and analyze distributed data.However,it inherits many security and privacy challenges of cloud computing,such as:authentication and access control.To address these problem,we proposed a new efficient privacy-preserving aggregation scheme for edge computing.Our scheme consists of two steps.First,we divided the data of the end users with the Simulated Annealing Module Partition(SAMP)algorithm.And then,the end sensors and edge nodes performed respectively differential aggregation mechanism with the Differential Aggregation Encryption(DAE)algorithm which can make noise interference and encryption algorithm with trusted authority(TA).Experiment results show that the DAE can preserve user privacy,and has significantly less computation and communication overhead than existing approaches. 展开更多
关键词 Edge computing data aggregation ENCRYPTION Simulated annealing
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Do biometric payment systems work during the COVID-19 pandemic?Insights from the Spanish users’viewpoint 被引量:2
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作者 Francisco Liébana-Cabanillas Francisco Muñoz-Leiva +1 位作者 Sebastián Molinillo Elena Higueras-Castillo 《Financial Innovation》 2022年第1期770-794,共25页
Technological developments are changing how users pay for goods and services.In the context of the COVID-19(coronavirus disease 2019)pandemic,new payment systems have been established to reduce contact between buyer a... Technological developments are changing how users pay for goods and services.In the context of the COVID-19(coronavirus disease 2019)pandemic,new payment systems have been established to reduce contact between buyer and seller.In addition to the pandemic,the future is payment processing is also uncertain due to the new EU security regulations of the Payment Services Directive(PSD2).Biometric payments one option that would guarantee the security of transactions and reduce the risk of conta-gion.This research analyses the intention to recommend the use of the mobile phone as a tool for collecting payments in a shop using iris reading as a biometric measure of the buyer.The moderating effect of the fear of contagion in the proposed relationships was also analysed.An online survey was carried out,which yielded a sample of 368 respondents.The results indicate that the main antecedents of intention to use,which precedes intention to recommend,are perceived trust,habit,personal innovativeness and comfort of use.Additionally,the moderating effect of COVID-19 was checked among users with a higher perception of risk.The results obtained have interesting implications for purchase management among manufacturers and retailers. 展开更多
关键词 Biometric payment systems Intention to recommend COVID-19 FEAR
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Influence of Rice Residue Management Techniques and Weed Control Treatments on Soil Available Plant Nutrients in Rice-Wheat Cropping System 被引量:1
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作者 Amandeep Singh Brar Parmodh Sharma +1 位作者 Charanjit Singh Kahlon Ujagar Singh Walia 《American Journal of Plant Sciences》 2019年第1期55-64,共10页
Rice-wheat is the predominant cropping system of fertile soils of Indian, Pakistan, Bangladesh and Nepal falling in the alluvial Indo-Gangetic Plains (IGP). Management of rice residues produced after the harvest of ri... Rice-wheat is the predominant cropping system of fertile soils of Indian, Pakistan, Bangladesh and Nepal falling in the alluvial Indo-Gangetic Plains (IGP). Management of rice residues produced after the harvest of rice crop and before sowing of the next wheat crop is a big challenge in that area. Mostly farmers burn rice residues assuming it low profile fodder and of little use. Burning of rice residues deprives the fields from many plant nutrients as they are lost during burning along with environmental pollutions and other issues. A field study was conducted for two consecutive years at the experimental area of the Department of Agronomy, Punjab Agricultural University, Ludhiana (India) to assess the impact of different rice residue management techniques and weed control treatments in wheat on soil available plant nutrients in rice-wheat cropping system. The experiment was laid out in split plot design with three replications. In main plots, five rice residue management treatments viz., no rice residue, rice residue 5 t·ha-1 (surface), rice residue 6 t·ha-1 (surface), rice residue 7 t·ha-1 (surface) and rice residue 5 t·ha-1 (incorporation) were settled and in sub plots, four weed control treatments i.e. clodinafop 60 t·ha-1, sulfosulfuron 25 t·ha-1, mesosulfuron + iodosulfuron 12 t·ha-1 and control (unweeded) were arranged. Results of the study revealed that surface application as well as incorporation of rice residues improved the organic carbon and NPK status than no rice residues. Among the residue management practices, incorporation of rice residues 5 t·ha-1 significantly improved the soil organic carbon, available nitrogen, phosphorus and potassium than no rice residue treatment in the 0 - 15 soil layer during both the years. Same trend was observed for 15 - 30 cm soil layer but differences were less wide than 0 - 15 cm soil layer. Among the weed control treatments, organic carbon was not significantly influenced. Herbicide treated plots registered significantly higher available nitrogen, phosphorus and potassium than control (unweeded) treatment in the 0 - 15 cm soil layer during both the years. 展开更多
关键词 RESIDUE Management RICE RESIDUE WEED Control
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MIMO-Terahertz in 6G Nano-Communications:Channel Modeling and Analysis 被引量:6
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作者 Shahid Bashir Mohammed H.Alsharif +4 位作者 Imran Khan Mahmoud A.Albreem Aduwati Sali Borhanuddin Mohd Ali Wonjong Noh 《Computers, Materials & Continua》 SCIE EI 2021年第1期263-274,共12页
With the development of wireless mobile communication technology,the demand for wireless communication rate and frequency increases year by year.Existing wireless mobile communication frequency tends to be saturated,w... With the development of wireless mobile communication technology,the demand for wireless communication rate and frequency increases year by year.Existing wireless mobile communication frequency tends to be saturated,which demands for new solutions.Terahertz(THz)communication has great potential for the future mobile communications(Beyond 5G),and is also an important technique for the high data rate transmission in spatial information network.THz communication has great application prospects in military-civilian integration and coordinated development.In China,important breakthroughs have been achieved for the key techniques of THz high data rate communications,which is practically keeping up with the most advanced technological level in the world.Therefore,further intensifying efforts on the development of THz communication have the strategic importance for China in leading the development of future wireless communication techniques and the standardization process of Beyond 5G.This paper analyzes the performance of the MIMO channel in the Terahertz(THz)band and a discrete mathematical method is used to propose a novel channel model.Then,a channel capacity model is proposed by the combination of path loss and molecular absorption in the THz band based on the CSI at the receiver.Simulation results show that the integration of MIMO in the THz band gives better data rate and channel capacity as compared with a single channel. 展开更多
关键词 Wireless communication 6G mobile communication terahertz communication MIMO channel modeling
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Analysis on the Problems and Countermeasures of Urban Wetland Park Tourism 被引量:1
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作者 YANG Dongxu LI Wenming 《Journal of Landscape Research》 2017年第3期112-114,共3页
Wetland with biological and ecological diversity, which can regulate regional climate, humidity, temperature, etc., has high tourism value. Development and management of wetland park in China started late, so we shoul... Wetland with biological and ecological diversity, which can regulate regional climate, humidity, temperature, etc., has high tourism value. Development and management of wetland park in China started late, so we should establish explicit goals to adjust wetland management and publicity from the aspects of regularity, professionality and availability, to promote the sustainable development of wetland resources. 展开更多
关键词 WETLAND PARK TOURISM PROBLEM COUNTERMEASURE
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The Boundedness of Multilinear Commutators on Grand Variable Herz Spaces 被引量:1
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作者 PENG Shan-shan CHEN Ji-li 《Chinese Quarterly Journal of Mathematics》 2022年第2期203-213,共11页
We consider multilinear commutators of singular integrals de ned by T→bf(x)=∫R^(n)mПi=1(bi(x)-bi(y))K(x,y)f(y)dy,where K is a standard Calderon-Zygmund kernel,m is a positive integer and~b=(b_(1);b_(2);…;b_(m))is ... We consider multilinear commutators of singular integrals de ned by T→bf(x)=∫R^(n)mПi=1(bi(x)-bi(y))K(x,y)f(y)dy,where K is a standard Calderon-Zygmund kernel,m is a positive integer and~b=(b_(1);b_(2);…;b_(m))is a family of m locally integrable functions.Based on the theory of variable exponent and on generalization of the BMO norm,we prove the boundedness of multilinear commutators T_(b) on grand variable Herz spaces.The result is still new even in the special case of m=1. 展开更多
关键词 Grand Herz space Variable exponent Multilinear commutators
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Analysis of Material Loss Behavior According to Long-Term Experiments on LDIE-FAC Multiple Degradation of Carbon Steel Materials 被引量:1
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作者 Kyeong Mo Hwang Dong Jin Lee +2 位作者 Hun Yun Seung Chang Yoo Ji Hyeon Kim 《World Journal of Nuclear Science and Technology》 2022年第1期1-10,共10页
Recently, damage caused by liquid droplet impingement erosion (LDIE) in addition to flow-accelerated corrosion (FAC) has frequently occurred in the secondary side steam piping of nuclear power plants, and the damage-o... Recently, damage caused by liquid droplet impingement erosion (LDIE) in addition to flow-accelerated corrosion (FAC) has frequently occurred in the secondary side steam piping of nuclear power plants, and the damage-occurring frequency is expected to increase as their operating years’ increase. In order to scrutinize its causes, therefore, an experimental study was conducted to understand how the behavior of LDIE-FAC multiple degradation changes when the piping of nuclear power plants is operated for a long time. Experimental results show that more magnetite was formed on the surface of the carbon steel specimen than on the low-alloy steel specimen, and that the rate of magnetite formation and extinction reached equilibrium due to the complex action of liquid droplet impingement erosion and flow-accelerated corrosion after a certain period of time. Furthermore, it was confirmed at the beginning of the experiment that A106 Gr.B specimen has more mass loss than A335 P22 specimen. After a certain period of time, however, the mass loss tends to be the opposite. This is presumed to have resulted from the magnetite formed on the surface playing a role in suppressing liquid droplet impingement erosion. In addition, it was confirmed that the amount of erosion linearly increases under the conditions in which the formation and extinction of magnetite reach equilibrium. 展开更多
关键词 Liquid Droplet Impingement Erosion (LDIE) Flow-Accelerated Corrosion (FAC) Multiple Degradations ToSPACE Wall Thinning MAGNETITE
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EXAFS Studies on Local Atomic Structure in the Amorphous Mg_(65)Cu_(25)Gd_(10) Alloy
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作者 李国强 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2011年第1期98-101,共4页
Local atomic structures of an amorphous Mg65Cu25Gd10 alloy and the structural changes by thermal annealing have been studied by extended X-ray absorption fine structure (EXAFS). The correlation between structural ch... Local atomic structures of an amorphous Mg65Cu25Gd10 alloy and the structural changes by thermal annealing have been studied by extended X-ray absorption fine structure (EXAFS). The correlation between structural changes and mechanical properties for the Mg65Cu25Gd10 alloy has also been discussed. Results showed that Cu atoms around Gd in Mg65Cu25Gd10 lost rapidly during annealing , resulting in the segregation of Cu atoms. The coordination number NGd-Mg of Mg65Cu25Gd10 annealed at 373 K first diminished and then augmented with the increase of annealing time. The formation of polyhedral short-range order unit with coordination number of nearly 12 around Gd atoms is in favor of the improvement of mechanical properties. The chemical short-range order, not topological short-range order in the amorphous Mg65Cu25Gd10 alloy had obvious changes during annealing. 展开更多
关键词 magnesium alloy amorphous alloy SHORT-RANGE EXAFS mechanical properties ANNEALING
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Wave Pressure Acting on V-Shaped Floating Breakwater in Random Seas
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作者 YU Yang DING Ning +1 位作者 LIN Jie HOU Jiajia 《Journal of Ocean University of China》 SCIE CAS 2015年第6期975-981,共7页
Wave pressure on the wet surface of a V-shaped floating breakwater in random seas is investigated. Considering the diffraction effect, the unit velocity potential caused by the single regular waves around the breakwat... Wave pressure on the wet surface of a V-shaped floating breakwater in random seas is investigated. Considering the diffraction effect, the unit velocity potential caused by the single regular waves around the breakwater is solved using the finite-depth Green function and boundary element method, in which the Green function is solved by integral method. The Response-Amplitude Operator(RAO) of wave pressure is acquired according to the Longuet-Higgins' wave model and the linear Bernoulli equation. Furthermore, the wave pressure's response spectrum is calculated according to the wave spectrum by discretizing the frequency domain. The wave pressure's characteristic value corresponding to certain cumulative probability is determined according to the Rayleigh distribution of wave heights. The numerical results and field test results are compared, which indicates that the wave pressure calculated in random seas agrees with that of field measurements. It is found that the bigger angle between legs will cause the bigger pressure response, while the increase in leg length does not influence the pressure significantly. The pressure at the side of head sea is larger than that of back waves. When the incident wave angle changes from 0? to 90?, the pressure at the side of back waves decreases clearly, while at the side of head sea, the situation is more complicated and there seems no obvious tendency. The concentration of wave energy around low frequency(long wavelength) will induce bigger wave pressure, and more attention should be paid to this situation for the structure safety. 展开更多
关键词 RANDOM SEAS V-SHAPED FLOATING BREAKWATER wave pressure boundary element method spectrum analysis
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