The US economy has emerged from the recent financial crisis and embarked on a path of recovery. A key response of the US government to the crisis was to restore the health of crisis-ridden financial institutions throu...The US economy has emerged from the recent financial crisis and embarked on a path of recovery. A key response of the US government to the crisis was to restore the health of crisis-ridden financial institutions through direct fiscal relief and continuous quantitative easing and pumping sufficient liquidity into the financial markets. Fortunately, this process did not give rise to widely feared vicious inflation or post-crisis depression. Does this suggest that as long as the central bank offers unlimited loans or economic assistance to crisis-ridden entities to restore their health, a crisis can be averted? If this conclusion holds true, does this mean that the theory of cyclical economic crisis has failed? What is the new theoretical methodology to avoid economic crises? The answers to these questions will guide us in preventing and responding to financial or economic crises in the future.展开更多
A single product closed-loop supply chain that satisfies an uncertain market demand with original and remanufactured products is considered.The yield of the recovery process is random and depends on the acquisition pr...A single product closed-loop supply chain that satisfies an uncertain market demand with original and remanufactured products is considered.The yield of the recovery process is random and depends on the acquisition price offered for the end-of-life products.In such a stochastic setting,a firm needs to make production and procurement decisions so that the total expected profit is maximized.Both centralized and decentralized models are established depending on the party collecting the returns.The optimal acquisition price and production quantities of original and remanufactured products are determined for the firm.The contracts to coordinate the decentralized systems are chosen and the optimal contract parameters are determined.A computational experiment is given to show the effects of recovery parameters on the system performance.Results show that the recovery parameters have a high impact on the profitability of the manufacturer in the centralized model and on that of the collection agency in the decentralized model.展开更多
Plane detection is a prerequisite for many computer vision tasks. This paper proposes a new method which can automatically detect planes from two projective images. Firstly, we modify Scott’s feature point matching m...Plane detection is a prerequisite for many computer vision tasks. This paper proposes a new method which can automatically detect planes from two projective images. Firstly, we modify Scott’s feature point matching method by post-processing its result with the concept of similarity, and then get the lines matching according to feature points matching based on the approximate invariance of the features’ distribution between two images. Finally, we group all feature points into subsets in terms of their geometric relations with feature lines as initial sets to estimate homography rather than by a random search strategy (like RANSAC) as in most existing methods. The proposed method is especially suitable to detecting planes in man-made scenes. This method is validated on real images.展开更多
The soft rock's heterogeneity and nonlinear mechanical behavior cause extremely difficult maintenance on the soft rock roadway. Aiming at the asymmetric deformation and destruction phenomenon appearing after excav...The soft rock's heterogeneity and nonlinear mechanical behavior cause extremely difficult maintenance on the soft rock roadway. Aiming at the asymmetric deformation and destruction phenomenon appearing after excavating and supporting the 7101 air return way in Meihe mine, this paper comprehensively adopted a variety of methods to analyze the roadway surrounding rock deformation rule, obtaining the roadway surrounding rock stress and plastic zone distribution rule under no supporting condition and the roadway surrounding rock deformation features under original symmetric supporting condition.Furthermore, this paper revealed the catastrophe mechanism, and proposed the concept of ‘‘weak structure'' and the disaster countermeasure of ‘‘overall stabilizing the roadway and strengthening the support of weak structure''. The industrial test shows that the disaster control technology can realize the coordination deformation of the supporting structure and roadway surrounding rock, thus significantly controlling the deformation of roadway surrounding rock.展开更多
Luffing mechanism is a key component of the construction machinery.This paper proposes a two degree of freedom(2-DOF)luffing mechanism,which has one more pair of driving cylinders than the single DOF luffing mechanism...Luffing mechanism is a key component of the construction machinery.This paper proposes a two degree of freedom(2-DOF)luffing mechanism,which has one more pair of driving cylinders than the single DOF luffing mechanism,to improve the performance of the machinery.To establish the dynamic model of the 2-DOF luffing mechanism,firstly,we develop a hierarchical method to deduce the Jacobian matrix and Hessian matrix for obtaining the kinematics equations.Subsequently,we divide the luffing mechanism into six bodies considering actuators,and deduce the kinetic equations of each body by the Newton-Euler method.Based on the dynamic model,we simulate the luffing process.Finally,a prototype is built on a pile driver to validate the model.Simulations and experiments show that the dynamic model can reflect the dynamic properties of the proposed luffing mechanism.And the control strategy that the front cylinders retract first shows better mechanical behavior than the other two control strategies.This research provides a reference for the design and application of 2-DOF luffing mechanism on construction machinery.The modeling approach can also be applied to similar mechanism with serial closed kinematic chains,which allows to calculate the dynamic parameters easily and exactly.展开更多
The importance attached to the need for sustainable development in the coastal areas is increasing. A management plan is required to minimize the environmental destruction resulting from the complexity of the property...The importance attached to the need for sustainable development in the coastal areas is increasing. A management plan is required to minimize the environmental destruction resulting from the complexity of the property in coastal areas, of human activities and of natural systems and to utilize the coastal resources effectively. The utilization of coasts, besides becoming very important particularly in views of tourism, has faced pressures caused by huge. These areas are mostly self-contradictory demands for the environmental protection. The project is an EU Life Long Learning Programme Project and the project duration is 24 months. The aim of the CoastLearn in Black Sea (CLBS) is to mobilize the human resources in the tourism and coastal management sector in Black Sea in general and notably Sinop, Varna and Constanta by raising awareness among the local decision making mechanisms of the integrated coastal zone management in order to encourage people to utilize the coastal resources in a coherent and balanced way.展开更多
Abstract: This study discusses the benefits of establishing a broader discipline of water science, based on the organizing mechanism of PES-W (payments for ecosystem services on the watershed scale). PES-W is deriv...Abstract: This study discusses the benefits of establishing a broader discipline of water science, based on the organizing mechanism of PES-W (payments for ecosystem services on the watershed scale). PES-W is derived from an extension of governance analyses of 163 watershed-based PES (payments for ecosystem services) programs, and from the integrative decision mechanism of IPES (integrated payments for ecosystem services) to generalize the PES approach. PES-W reflects three interrelated perspectives fundamental to the global science of integrated water governance: (1) the ecological and economic perspective to integrate human incentives for integrated water resources governance; (2) the sociological and ecological perspective to form partnerships for meta-monitoring and recta-funding for integrated watershed governance; and (3) the scientific and sociological perspective to develop organizing botmdaries based on technology, lifestyle, entrepreneurship and organizing infrastructure for integrated aquatic ecosystem governance. This study is intended to communicate with the international scientific communities for establishing an advanced, academic, and practical multidisciplinary field of the global science of integrated water governance as a critical condition for sustainable development in human societies.展开更多
Based on a case study of Longyou County, Zhejiang Province, the decision tree, a data mining method, was used to analyze the relationships between soil organic matter (SOM) and other environmental and satellite sensin...Based on a case study of Longyou County, Zhejiang Province, the decision tree, a data mining method, was used to analyze the relationships between soil organic matter (SOM) and other environmental and satellite sensing spatial data. The decision tree associated SOM content with some extensive easily observable landscape attributes, such as landform, geology, land use, and remote sensing images, thus transforming the SOM-related information into a clear, quantitative, landscape factor-associated regular syst…展开更多
A novel control system is developed to improve the capabilities of robet hand performing tasks in a variety of environments. A joint impedance control strategy has been successfully implemented in the low level contro...A novel control system is developed to improve the capabilities of robet hand performing tasks in a variety of environments. A joint impedance control strategy has been successfully implemented in the low level control of a highly integrated robot hand. At flint, a real time controller with DSP&FPGA-based multilevel control architecture is built. Then a current sensor of the single direct current (DC) link is used to measure and reconstruct the three phase currents, and a stable current signal is measured by optimizing sample instant. The experimental results of the joint impedance control show that the proposed method not only improves the effectiveness of contact environment performance, but also provides compliant interaction of robot hand with a person, which is very important for the development of friendly human robot of the next generation.展开更多
Based on the literature review of environmental anti-pollution researches, this paper analyzes the administra- tive mechanism of Huaihe River anti-pollution with game theory. Based on the quantitative analysis on thre...Based on the literature review of environmental anti-pollution researches, this paper analyzes the administra- tive mechanism of Huaihe River anti-pollution with game theory. Based on the quantitative analysis on three correspond- ing game models with four players including local residents, enterprises, local governments and competent authorities at higher levels, this paper demonstrates four main shortcomings of current administrative mechanism of Huaihe River anti-pollution system, including low emission cost, low connivance cost, overemphasis on heavy fine of the enterprises, neglect of the punishment on the local departments and intersected administrative mechanism. This paper sets up anti- pollution administrative mechanism, combining economic method with noneconomic method, government control with market mechanism, and introducing public participation. At last, this paper proposes policies, such as implementing emissions trading system, reforming public participation system, and reforming government’s environmental protection mechanism to promote law enforcement.展开更多
In order to make strategic decision on firms’ sharing reward program( SRP), a nested Stackelberg game is developed. The sharing behavior among users and the rewarding strategy of firms are modeled. The optimal sharin...In order to make strategic decision on firms’ sharing reward program( SRP), a nested Stackelberg game is developed. The sharing behavior among users and the rewarding strategy of firms are modeled. The optimal sharing bonus is worked out and the impact of social relationships among customers is discussed. The results show that the higher the bonus,the more efforts the inductor is willing to make to persuade the inductee into buying. In addition,the firms should take the social relationship into consideration when setting the optimal sharing bonus. If the social relationship is weak,there is no need to adopt the SRP. Otherwise,there are two ways to reward the inductors. Also,the stronger the social relationship,the fewer the sharing bonuses that should be offered to the inductors,and the higher the expected profits. As a result,it is reasonable for the firms to implement SRPs on the social media where users are familiar with each other.展开更多
In this paper, the authors present a new control strategy for continuous backbone (continuum) "trunk and tentacle" robots. Control of this emerging new class of robots has proved difficult due to the inherent comp...In this paper, the authors present a new control strategy for continuous backbone (continuum) "trunk and tentacle" robots. Control of this emerging new class of robots has proved difficult due to the inherent complexity of their dynamics. Using a recently established full dynamic model, the authors introduce a new nonlinear model-based control strategy for continuum robots. The approach is applicable to continuum robots which can extend/contract as well as bend throughout their structure. Results are illustrated using the mathematical model of a three-section, six-degree of freedom planar continuum robot.展开更多
Display devices have significantly changed our daily life for decades,from the watches,television,to the laptop and smartphone.As the desire of advanced display device with high-resolution,long operation life and ligh...Display devices have significantly changed our daily life for decades,from the watches,television,to the laptop and smartphone.As the desire of advanced display device with high-resolution,long operation life and lightweight properties,several display techniques have been demonstrated.There are mainly four types of electronic display device:cathode ray tube(CRT),liquid-crystal display(LCD),organic light-emitting diode(OLED),and micro-LED.Due to the different working principles and device structures,each type of display device has its special characteristic properties.The performance of devices could be adjusted through the material selection or device design.With careful device structure regulation,not only the efficiency but also the stability would be improved.Herein,a brief review of innovative strategies towards the structure design is presented.展开更多
Human activities including modern agriculture have caused environmental pollution, so people begin to pay attentton to safe food. As a result, organic agriculture has emerged. Organic agriculture in South Korea (here...Human activities including modern agriculture have caused environmental pollution, so people begin to pay attentton to safe food. As a result, organic agriculture has emerged. Organic agriculture in South Korea (hereinafter referred as Korea) and China has developed rapidly since the appearance of organic agriculture in 1970s and 1980s respectively. Organic agriculture in China and Korea has developed steadily through agricultural support policies, certification management, institutions construction etc. In the development of organtc agriculture, China and Korea are now facing some technical and extension problems. In general however the development of organic agriculture in China lags behind Korea. China can learn from the experience about the development of organic agriculture in Korea to solve contradiction between development of organic agriculture and food safety, to strengthen the organic food certification, to introduce a system of agricultural direct payment and other positive measures, thus will guarantee steady and healthy development of organic agriculture in China.展开更多
Weeds normally grow in patches and spatially distributed in field. Patch spraying to control weeds has advantages of chemical saving, reduced cost and environmental pollution. Advent of electro-optical sensing capabil...Weeds normally grow in patches and spatially distributed in field. Patch spraying to control weeds has advantages of chemical saving, reduced cost and environmental pollution. Advent of electro-optical sensing capabilities has paved the way of using machine vision technologies for patch spraying. Machine vision system has to acquire and process digital images to make control decisions. Proper identification and classification of objects present in image holds the key to make control decisions and use of any spraying operation performed. Recognition of objects in digital image may be affected by background, intensity, image resolution, orientation of the object and geometrical characteristics. A set of 16, including 11 shape and 5 texture-based parameters coupled with predictive discriminating analysis has been used to identify the weed leaves. Geometrical features were indexed successfully to eliminate the effect of object orientation. Linear discriminating analysis was found to be more effective in correct classification of weed leaves. The classification accuracy of 69% to 80% was observed. These features can be utilized for development of image based variable rate sprayer.展开更多
In the past 70 years, Israel has not only realized the self-sufficiency of agricultural products, but also make its way to becoming one of leading exporters of agricultural products in the world rapidly. Undoubtedly, ...In the past 70 years, Israel has not only realized the self-sufficiency of agricultural products, but also make its way to becoming one of leading exporters of agricultural products in the world rapidly. Undoubtedly, there are many reasons for this world famous "Miracle of Negev Desert" [1], but we consider the decision making mechanism as one of the most important reasons, because such a perfect integrated system consisting of researching system, experimental system and extension system is well organized and it booms the development of agriculture in Israel.展开更多
Spectrum auction is an important approach of spectrum distribution in cognitive radio networks. However, a single secondary user(SU) probably can't afford the price of spectrum. Multiple SUs grouping together to p...Spectrum auction is an important approach of spectrum distribution in cognitive radio networks. However, a single secondary user(SU) probably can't afford the price of spectrum. Multiple SUs grouping together to participate in the auction as a whole is helpful to increase purchasing power. However, SUs could suffer from a new group cheating problem, i.e., parts of users conspire to manipulate the auction by submitting untruthful bids. Existing auction mechanisms were mainly designed to be strategy-proof only for individual user and can't deal with group cheating. In this paper, a novel spectrum auction mechanism called COSTAG(COst Sharing based Truthful Auction with Group-buying) is proposed to address the group cheating problem. COSTAG consists of a grouping rule to perform grouping and a payment rule to determine the market-clearing price in the spectrum auction. Different from single-echelon pricing approach employed in existing works, a multi-echelon pricing strategy is designed to increase the transaction rate and optimize social profit for the auction. Comprehensive theoretical analysis shows that COSTAG can satisfy the crucial economic robustness properties, both individual and group truthfulness. Simulations demonstrate that comparing with existing works, COSTAG can improve the system performance significantly.展开更多
A neural network integrated classifier(NNIC) designed with a new modulation recognition algorithm based on the decision-making tree is proposed in this paper.Firstly,instantaneous parameters are extracted in the time ...A neural network integrated classifier(NNIC) designed with a new modulation recognition algorithm based on the decision-making tree is proposed in this paper.Firstly,instantaneous parameters are extracted in the time domain by the coordinated rotation digital computer(CORDIC) algorithm based on the extended convergence domain and feature parameters of frequency spectrum and power spectrum are extracted by the time-frequency analysis method.All pattern identification parameters are calculated under the I/Q orthogonal two-channel structure,and constructed into the feature vector set.Next,the classifier is designed according to the modulation pattern and recognition performance of the feature parameter set,the optimum threshold is selected for each feature parameter based on the decision-making mechanism in a single classifier,multi-source information fusion and modulation recognition are realized based on feature parameter judge process in the NNIC.Simulation results show NNIC is competent for all modulation recognitions,8 kinds of digital modulated signals are effectively identified,which shows the recognition rate and anti-interference capability at low SNR are improved greatly,the overall recognition rate can reach 100%when SNR is12dB.展开更多
文摘The US economy has emerged from the recent financial crisis and embarked on a path of recovery. A key response of the US government to the crisis was to restore the health of crisis-ridden financial institutions through direct fiscal relief and continuous quantitative easing and pumping sufficient liquidity into the financial markets. Fortunately, this process did not give rise to widely feared vicious inflation or post-crisis depression. Does this suggest that as long as the central bank offers unlimited loans or economic assistance to crisis-ridden entities to restore their health, a crisis can be averted? If this conclusion holds true, does this mean that the theory of cyclical economic crisis has failed? What is the new theoretical methodology to avoid economic crises? The answers to these questions will guide us in preventing and responding to financial or economic crises in the future.
基金The National Natural Science Foundation of China(No.70772059)
文摘A single product closed-loop supply chain that satisfies an uncertain market demand with original and remanufactured products is considered.The yield of the recovery process is random and depends on the acquisition price offered for the end-of-life products.In such a stochastic setting,a firm needs to make production and procurement decisions so that the total expected profit is maximized.Both centralized and decentralized models are established depending on the party collecting the returns.The optimal acquisition price and production quantities of original and remanufactured products are determined for the firm.The contracts to coordinate the decentralized systems are chosen and the optimal contract parameters are determined.A computational experiment is given to show the effects of recovery parameters on the system performance.Results show that the recovery parameters have a high impact on the profitability of the manufacturer in the centralized model and on that of the collection agency in the decentralized model.
文摘Plane detection is a prerequisite for many computer vision tasks. This paper proposes a new method which can automatically detect planes from two projective images. Firstly, we modify Scott’s feature point matching method by post-processing its result with the concept of similarity, and then get the lines matching according to feature points matching based on the approximate invariance of the features’ distribution between two images. Finally, we group all feature points into subsets in terms of their geometric relations with feature lines as initial sets to estimate homography rather than by a random search strategy (like RANSAC) as in most existing methods. The proposed method is especially suitable to detecting planes in man-made scenes. This method is validated on real images.
基金provided by the National Natural Science Foundation of China(Nos.51204166 and51174195)the Jiangsu Province ordinary university graduate research innovation projects(No.CXZZ12_0954)
文摘The soft rock's heterogeneity and nonlinear mechanical behavior cause extremely difficult maintenance on the soft rock roadway. Aiming at the asymmetric deformation and destruction phenomenon appearing after excavating and supporting the 7101 air return way in Meihe mine, this paper comprehensively adopted a variety of methods to analyze the roadway surrounding rock deformation rule, obtaining the roadway surrounding rock stress and plastic zone distribution rule under no supporting condition and the roadway surrounding rock deformation features under original symmetric supporting condition.Furthermore, this paper revealed the catastrophe mechanism, and proposed the concept of ‘‘weak structure'' and the disaster countermeasure of ‘‘overall stabilizing the roadway and strengthening the support of weak structure''. The industrial test shows that the disaster control technology can realize the coordination deformation of the supporting structure and roadway surrounding rock, thus significantly controlling the deformation of roadway surrounding rock.
基金Project(2015B020238014)supported by the Science and Technology Program of Guangdong Province,China。
文摘Luffing mechanism is a key component of the construction machinery.This paper proposes a two degree of freedom(2-DOF)luffing mechanism,which has one more pair of driving cylinders than the single DOF luffing mechanism,to improve the performance of the machinery.To establish the dynamic model of the 2-DOF luffing mechanism,firstly,we develop a hierarchical method to deduce the Jacobian matrix and Hessian matrix for obtaining the kinematics equations.Subsequently,we divide the luffing mechanism into six bodies considering actuators,and deduce the kinetic equations of each body by the Newton-Euler method.Based on the dynamic model,we simulate the luffing process.Finally,a prototype is built on a pile driver to validate the model.Simulations and experiments show that the dynamic model can reflect the dynamic properties of the proposed luffing mechanism.And the control strategy that the front cylinders retract first shows better mechanical behavior than the other two control strategies.This research provides a reference for the design and application of 2-DOF luffing mechanism on construction machinery.The modeling approach can also be applied to similar mechanism with serial closed kinematic chains,which allows to calculate the dynamic parameters easily and exactly.
文摘The importance attached to the need for sustainable development in the coastal areas is increasing. A management plan is required to minimize the environmental destruction resulting from the complexity of the property in coastal areas, of human activities and of natural systems and to utilize the coastal resources effectively. The utilization of coasts, besides becoming very important particularly in views of tourism, has faced pressures caused by huge. These areas are mostly self-contradictory demands for the environmental protection. The project is an EU Life Long Learning Programme Project and the project duration is 24 months. The aim of the CoastLearn in Black Sea (CLBS) is to mobilize the human resources in the tourism and coastal management sector in Black Sea in general and notably Sinop, Varna and Constanta by raising awareness among the local decision making mechanisms of the integrated coastal zone management in order to encourage people to utilize the coastal resources in a coherent and balanced way.
文摘Abstract: This study discusses the benefits of establishing a broader discipline of water science, based on the organizing mechanism of PES-W (payments for ecosystem services on the watershed scale). PES-W is derived from an extension of governance analyses of 163 watershed-based PES (payments for ecosystem services) programs, and from the integrative decision mechanism of IPES (integrated payments for ecosystem services) to generalize the PES approach. PES-W reflects three interrelated perspectives fundamental to the global science of integrated water governance: (1) the ecological and economic perspective to integrate human incentives for integrated water resources governance; (2) the sociological and ecological perspective to form partnerships for meta-monitoring and recta-funding for integrated watershed governance; and (3) the scientific and sociological perspective to develop organizing botmdaries based on technology, lifestyle, entrepreneurship and organizing infrastructure for integrated aquatic ecosystem governance. This study is intended to communicate with the international scientific communities for establishing an advanced, academic, and practical multidisciplinary field of the global science of integrated water governance as a critical condition for sustainable development in human societies.
文摘Based on a case study of Longyou County, Zhejiang Province, the decision tree, a data mining method, was used to analyze the relationships between soil organic matter (SOM) and other environmental and satellite sensing spatial data. The decision tree associated SOM content with some extensive easily observable landscape attributes, such as landform, geology, land use, and remote sensing images, thus transforming the SOM-related information into a clear, quantitative, landscape factor-associated regular syst…
文摘A novel control system is developed to improve the capabilities of robet hand performing tasks in a variety of environments. A joint impedance control strategy has been successfully implemented in the low level control of a highly integrated robot hand. At flint, a real time controller with DSP&FPGA-based multilevel control architecture is built. Then a current sensor of the single direct current (DC) link is used to measure and reconstruct the three phase currents, and a stable current signal is measured by optimizing sample instant. The experimental results of the joint impedance control show that the proposed method not only improves the effectiveness of contact environment performance, but also provides compliant interaction of robot hand with a person, which is very important for the development of friendly human robot of the next generation.
文摘Based on the literature review of environmental anti-pollution researches, this paper analyzes the administra- tive mechanism of Huaihe River anti-pollution with game theory. Based on the quantitative analysis on three correspond- ing game models with four players including local residents, enterprises, local governments and competent authorities at higher levels, this paper demonstrates four main shortcomings of current administrative mechanism of Huaihe River anti-pollution system, including low emission cost, low connivance cost, overemphasis on heavy fine of the enterprises, neglect of the punishment on the local departments and intersected administrative mechanism. This paper sets up anti- pollution administrative mechanism, combining economic method with noneconomic method, government control with market mechanism, and introducing public participation. At last, this paper proposes policies, such as implementing emissions trading system, reforming public participation system, and reforming government’s environmental protection mechanism to promote law enforcement.
基金The National Social Science Foundation of China(No.17BGL196)the Postgraduate Research&Practice Innovation Program of Jiangsu Province(No.KYLX15_0193)
文摘In order to make strategic decision on firms’ sharing reward program( SRP), a nested Stackelberg game is developed. The sharing behavior among users and the rewarding strategy of firms are modeled. The optimal sharing bonus is worked out and the impact of social relationships among customers is discussed. The results show that the higher the bonus,the more efforts the inductor is willing to make to persuade the inductee into buying. In addition,the firms should take the social relationship into consideration when setting the optimal sharing bonus. If the social relationship is weak,there is no need to adopt the SRP. Otherwise,there are two ways to reward the inductors. Also,the stronger the social relationship,the fewer the sharing bonuses that should be offered to the inductors,and the higher the expected profits. As a result,it is reasonable for the firms to implement SRPs on the social media where users are familiar with each other.
文摘In this paper, the authors present a new control strategy for continuous backbone (continuum) "trunk and tentacle" robots. Control of this emerging new class of robots has proved difficult due to the inherent complexity of their dynamics. Using a recently established full dynamic model, the authors introduce a new nonlinear model-based control strategy for continuum robots. The approach is applicable to continuum robots which can extend/contract as well as bend throughout their structure. Results are illustrated using the mathematical model of a three-section, six-degree of freedom planar continuum robot.
基金Projects(71572028,71872027)supported by the National Natural Science Foundation of China。
文摘Display devices have significantly changed our daily life for decades,from the watches,television,to the laptop and smartphone.As the desire of advanced display device with high-resolution,long operation life and lightweight properties,several display techniques have been demonstrated.There are mainly four types of electronic display device:cathode ray tube(CRT),liquid-crystal display(LCD),organic light-emitting diode(OLED),and micro-LED.Due to the different working principles and device structures,each type of display device has its special characteristic properties.The performance of devices could be adjusted through the material selection or device design.With careful device structure regulation,not only the efficiency but also the stability would be improved.Herein,a brief review of innovative strategies towards the structure design is presented.
文摘Human activities including modern agriculture have caused environmental pollution, so people begin to pay attentton to safe food. As a result, organic agriculture has emerged. Organic agriculture in South Korea (hereinafter referred as Korea) and China has developed rapidly since the appearance of organic agriculture in 1970s and 1980s respectively. Organic agriculture in China and Korea has developed steadily through agricultural support policies, certification management, institutions construction etc. In the development of organtc agriculture, China and Korea are now facing some technical and extension problems. In general however the development of organic agriculture in China lags behind Korea. China can learn from the experience about the development of organic agriculture in Korea to solve contradiction between development of organic agriculture and food safety, to strengthen the organic food certification, to introduce a system of agricultural direct payment and other positive measures, thus will guarantee steady and healthy development of organic agriculture in China.
文摘Weeds normally grow in patches and spatially distributed in field. Patch spraying to control weeds has advantages of chemical saving, reduced cost and environmental pollution. Advent of electro-optical sensing capabilities has paved the way of using machine vision technologies for patch spraying. Machine vision system has to acquire and process digital images to make control decisions. Proper identification and classification of objects present in image holds the key to make control decisions and use of any spraying operation performed. Recognition of objects in digital image may be affected by background, intensity, image resolution, orientation of the object and geometrical characteristics. A set of 16, including 11 shape and 5 texture-based parameters coupled with predictive discriminating analysis has been used to identify the weed leaves. Geometrical features were indexed successfully to eliminate the effect of object orientation. Linear discriminating analysis was found to be more effective in correct classification of weed leaves. The classification accuracy of 69% to 80% was observed. These features can be utilized for development of image based variable rate sprayer.
文摘In the past 70 years, Israel has not only realized the self-sufficiency of agricultural products, but also make its way to becoming one of leading exporters of agricultural products in the world rapidly. Undoubtedly, there are many reasons for this world famous "Miracle of Negev Desert" [1], but we consider the decision making mechanism as one of the most important reasons, because such a perfect integrated system consisting of researching system, experimental system and extension system is well organized and it booms the development of agriculture in Israel.
基金partially supported by the National Science Foundation of China (No. 61070211, No. 61003304, No 61501482 and No 61070201)Equipment research foundation (No.6140134040216)the Ph.D. Programs Foundation of Ministry of Education of China (No. 20114307120003)
文摘Spectrum auction is an important approach of spectrum distribution in cognitive radio networks. However, a single secondary user(SU) probably can't afford the price of spectrum. Multiple SUs grouping together to participate in the auction as a whole is helpful to increase purchasing power. However, SUs could suffer from a new group cheating problem, i.e., parts of users conspire to manipulate the auction by submitting untruthful bids. Existing auction mechanisms were mainly designed to be strategy-proof only for individual user and can't deal with group cheating. In this paper, a novel spectrum auction mechanism called COSTAG(COst Sharing based Truthful Auction with Group-buying) is proposed to address the group cheating problem. COSTAG consists of a grouping rule to perform grouping and a payment rule to determine the market-clearing price in the spectrum auction. Different from single-echelon pricing approach employed in existing works, a multi-echelon pricing strategy is designed to increase the transaction rate and optimize social profit for the auction. Comprehensive theoretical analysis shows that COSTAG can satisfy the crucial economic robustness properties, both individual and group truthfulness. Simulations demonstrate that comparing with existing works, COSTAG can improve the system performance significantly.
基金Supported by the National Natural Science Foundation of China(No.61001049)Key Laboratory of Computer Architecture Opening Topic Fund Subsidization(CARCH201103)Beijing Natural Science Foundation(No.Z2002012201101)
文摘A neural network integrated classifier(NNIC) designed with a new modulation recognition algorithm based on the decision-making tree is proposed in this paper.Firstly,instantaneous parameters are extracted in the time domain by the coordinated rotation digital computer(CORDIC) algorithm based on the extended convergence domain and feature parameters of frequency spectrum and power spectrum are extracted by the time-frequency analysis method.All pattern identification parameters are calculated under the I/Q orthogonal two-channel structure,and constructed into the feature vector set.Next,the classifier is designed according to the modulation pattern and recognition performance of the feature parameter set,the optimum threshold is selected for each feature parameter based on the decision-making mechanism in a single classifier,multi-source information fusion and modulation recognition are realized based on feature parameter judge process in the NNIC.Simulation results show NNIC is competent for all modulation recognitions,8 kinds of digital modulated signals are effectively identified,which shows the recognition rate and anti-interference capability at low SNR are improved greatly,the overall recognition rate can reach 100%when SNR is12dB.