The status and supporting policies of cold chain logistics equipment man- agement and control in China were described. The connotation of Internet of Things and its impact on cold chain logistics equipment management ...The status and supporting policies of cold chain logistics equipment man- agement and control in China were described. The connotation of Internet of Things and its impact on cold chain logistics equipment management and control were ana- lyzed from external form to internal nature. Through introducing the value chain and relevant equipments of cold chain logistics, the correlation between the main technologies in Internet of Things and the common indices for cold chain logistics equipment management and control was analyzed in detail. The application values of Internet of Things technologies in cold chain logistics equipment management and control were illustrated, including the sample analysis on the application of radio-frequency identification (RFID). After the establishment of BSC performance evaluation index system of cold chain logistics equipment management and control, the optimization measures and suggestions on cold chain logistics equipment management and control under Internet of Things were put forward.展开更多
Based on the system of electric power supply for flexible manufacturing systems (FMS), a study has been carried out on the intelligent safety examination, monitoring and maintenance of its running environment. On the ...Based on the system of electric power supply for flexible manufacturing systems (FMS), a study has been carried out on the intelligent safety examination, monitoring and maintenance of its running environment. On the basis of the specific feature of the power supply network of an FMS, real time monitoring system of the power supply network and the fault diagnostic expert system for the power equipment have been designed. This system can diagnose not only definite fault phenomena, but also fuzzy, uncertain fault phenomena as well. Fault diagnostic knowledge base for the power equipment has been founded hierarchy architecture model and the method of fault tree analysis. Feasibility of this system has been proved by computer simulation.展开更多
With the popularity of smart handheld devices, mobile streaming video has multiplied the global network traffic in recent years. A huge concern of users' quality of experience(Qo E) has made rate adaptation method...With the popularity of smart handheld devices, mobile streaming video has multiplied the global network traffic in recent years. A huge concern of users' quality of experience(Qo E) has made rate adaptation methods very attractive. In this paper, we propose a two-phase rate adaptation strategy to improve users' real-time video Qo E. First, to measure and assess video Qo E, we provide a continuous Qo E prediction engine modeled by RNN recurrent neural network. Different from traditional Qo E models which consider the Qo E-aware factors separately or incompletely, our RNN-Qo E model accounts for three descriptive factors(video quality, rebuffering, and rate change) and reflects the impact of cognitive memory and recency. Besides, the video playing is separated into the initial startup phase and the steady playback phase, and we takes different optimization goals for each phase: the former aims at shortening the startup delay while the latter ameliorates the video quality and the rebufferings. Simulation results have shown that RNN-Qo E can follow the subjective Qo E quite well, and the proposed strategy can effectively reduce the occurrence of rebufferings caused by the mismatch between the requested video rates and the fluctuated throughput and attains standout performance on real-time Qo E compared with classical rate adaption methods.展开更多
This paper proposes a new access architecture onmobile cloud,which introduces a middle layer sitting between mobile devices and their cloud infrastructure.This middle layer is composed of cloudlets which are deployed ...This paper proposes a new access architecture onmobile cloud,which introduces a middle layer sitting between mobile devices and their cloud infrastructure.This middle layer is composed of cloudlets which are deployed by cloud services providers,such as wireless network access points(APs),to improve the performance of mobile cloud servicesand be different from traditional mobile operator mode.Then based on this new architecture.we improve our previous(Attribute-basedencryption) ABE access control scheme on cloud for mobile cloud,which is proposed to offload the main amount of computations to the cloudlet as the function of cloud.Simulationresults demonstratethe new access control scheme takes into consideration response time constraints and network statusof access task execution,while satisfying certain network security for mobile cloud.展开更多
Though the WiMedia supports higher data rates than other WPAN technologies,a WiMedia device cannot reach other devices that are separated from it by more than 10 m,which is the typical limited transmission range of th...Though the WiMedia supports higher data rates than other WPAN technologies,a WiMedia device cannot reach other devices that are separated from it by more than 10 m,which is the typical limited transmission range of the WiMedia protocol.In this work,we propose a multi-hop QoS routing protocol to enable WiMedia devices to transmit real-time data to devices that are located out of the transmission range.The proposed routing protocol is a hybrid algorithm,which mixes the table-driven and on-demand routing algorithms,searching one or more routes according to the number of hops to a destination device.WiMedia MAC is potentially capable of learning the existence of neighbor devices by using a beacon frame.By utilizing the neighbors' information,all devices can create routing entries for devices within 2-hops periodically.For devices beyond the 2-hop range,the newly designed on-demand routing algorithm is applied to multi-hop routing.If a routing entry for a destination device is not listed in the routing table,the source device sends a request packet to 2-hop range devices which could be found in the routing table.Since every device maintains routing entries for 2-hop range devices in the routing table,the request packet is replied in advance before its arrival at the destination device.Also,to decide the optimal route for a destination device,the number of medium access slots(MASs),received signal strength indicator(RSSI)and hop count are utilized to establish a QoS-enabled routing table.We perform ns-2 simulation to investigate the performance of the proposed routing protocol with AODV and DSDV.The simulation results show that the proposed protocol has better throughput and lower overhead than other protocols.展开更多
In this study, indoor air quality (IAQ) assessments were carried out in a screen printing facility. The air sampling was conducted in press department, including two different types of screen printing machines: sem...In this study, indoor air quality (IAQ) assessments were carried out in a screen printing facility. The air sampling was conducted in press department, including two different types of screen printing machines: semi-automatic and automatic. Air samples were collected and analyzed in situ for 4 times, once per 2 hours, during working time of 8 hours. Analysis of the experimental data showed that ambient ozone concentrations slowly increases with the increasing of TVOCs concentration and intensive use of UV lamps during automatic screen printing process. Therefore, the detected concentration levels of ozone and VOCs were compared with the Occupational Safety and Health Administration (OSHA) and Serbian Regulation. Comparison of the two mentioned standard regulations, the ozone concentrations in indoor printing air were from 0.83 to 8.1 and 2.4 to 16.2 times higher in the relation to the prescribed PEL and maximum allowed concentration (MAC) values, respectively, while the concentrations of particular VOCs were much below the PEL prescribed by the OSHA.展开更多
In Internet of Things(IoT), the devices or terminals are connected with each other, which can be very diverse over the wireless networks. Unfortunately, the current devices are not designed to communicate with the col...In Internet of Things(IoT), the devices or terminals are connected with each other, which can be very diverse over the wireless networks. Unfortunately, the current devices are not designed to communicate with the collocated devices which employ different communication technologies. Consequently, the communication between these devices will be realized only by using the gateway nodes. This will cause the inefficient use of wireless resources. Therefore, in this paper, a smart service system(SSS) architecture is proposed, which consists of smart service terminal(SST), and smart service network(SSN), to realize the Io T in a general environment with diverse communication networks, devices, and services. The proposed architecture has the following advantages: i) the devices in this architecture cover multiple types of terminals and sensor-actuator devices; ii) the communications network therein is a converged network, and will coordinate multiple kinds of existing and emerging networks. This converged network offers ubiquitous access for various sensors and terminals; iii) the architecture has services and applications covering all smart service areas. It also provides theadaptability to new services and applications. A SSS architecture-based smart campus system was developed and deployed. Evaluation experiments of the proposed smart campus system demonstrate the SSS's advantages over the existing counterparts, and verify the effectiveness of the proposed architecture.展开更多
This research explored the organization's public relationship management practices in corporate blogs on the web. Content analyses of corporate blogs of large Korean firms over two years in a longitudinal design reve...This research explored the organization's public relationship management practices in corporate blogs on the web. Content analyses of corporate blogs of large Korean firms over two years in a longitudinal design revealed that relationship management strategies of openness, positivity and sharing of tasks were featured relatively strongly, whereas networking, access, and assurances were enacted relatively weakly. Further, most Korean corporate blogs utilized a tightly controlled top-down strategy. In addition, the use level of relationship management strategy was tied to the kind of corporate blogging strategies, but not to the industry type of the firms. Although utilized the same social media device, corporate blogs enacted different purposes and relational management activities in different countries, indicating that corporate blogs are largely cultural and driven locally.展开更多
In order to optimize handover target selection and achieve better handover performance in cellular relay networks under the long term evolution (LTE) system, a novel handover measurement and decision scheme based on...In order to optimize handover target selection and achieve better handover performance in cellular relay networks under the long term evolution (LTE) system, a novel handover measurement and decision scheme based on cost function is proposed in the paper. The relay-enhanced network provides user equipment (UE) multiple handover choices from neighbor base stations or relays. This may result in different overhead, resource utility and traffic load which attaches importance to proper handover schemes. Compared with traditional handover measurement and decision schemes, the proposed scheme adopts reference signal receiving quality (RSRQ) in the measurement stage and uses a modified signal cost function considering signal overhead in different handover types and expected long-term throughput of UE. Besides, UE fairness and sector resource utilization are taken into account as well. Theory analysis and simulation results prove that the proposed scheme can enhance cell throughput, decrease handover delay and signal overhead, and improve UE fairness.展开更多
A novel 0.1% Pd-0.05% (mass fraction) Pt/stainless steel wire mesh catalyst was prepared for volatile organic compounds (VOCs) elimination. The catalyst was synthesized by stainless steel wire mesh as support and ...A novel 0.1% Pd-0.05% (mass fraction) Pt/stainless steel wire mesh catalyst was prepared for volatile organic compounds (VOCs) elimination. The catalyst was synthesized by stainless steel wire mesh as support and then treated by anodic oxidation technology to develop a porous membrane on the support. During the anodic oxidation process, various electrolytes were used to investigate the formation of porous membrane. And the catalytic performance of the catalysts was tested by using toluene and acetone combustion as model reaction. The temperatures of complete toluene and acetone conversion were decreased to 180℃ and 240 ℃, respectively. The morphologies of the stainless steel wire mesh supports and catalysts were characterized by means of scanning electron microscopy (SEM) and temperature-programmed reduction (TPR).展开更多
This paper describes the design and development of a wireless LAN (WLAN) access point based on Bluetooth and uClinux. To make the best use of high-speed serial communication capability, several methods such as modifyi...This paper describes the design and development of a wireless LAN (WLAN) access point based on Bluetooth and uClinux. To make the best use of high-speed serial communication capability, several methods such as modifying baud-rate of serial port driver, utilizing buffer area and adding flow-control were adopted. After analysis of scheduling and interruption handling, modifying the timer's parameters was put forward as a method to control the timer interrupt. In this way, data throughput and system stability were enhanced. Meanwhile, migration of the Bluetooth protocol stack was detailed and some successful applications of LAN access point were presented.展开更多
Device-to-Device(D2D) communication has been proposed to facilitate cellular network with system capacity(SC) and quality of service(QoS).We consider the design of link assignment(LA),channel allocation(CA)and power c...Device-to-Device(D2D) communication has been proposed to facilitate cellular network with system capacity(SC) and quality of service(QoS).We consider the design of link assignment(LA),channel allocation(CA)and power control(PC) in D2D-aided content delivery scenario for both user fairness(UF)and system throughput(ST) under QoS requirement.Due to the complexity of the problem,we decompose it into two components:CA is formulated from graph perspective to mitigate severe co-channel interference,which turns out to be the Max K-cut problem;LA and PC are jointly optimized to utilize the gain achieved from CA for supreme performance,and specifically,genetic algorithm(GA) is adopted to optimize LA,but when deriving the fitness of each chromosome,PC optimization will be involved.Thanks to numerical results,we elucidate the efficacy of our scheme.展开更多
According to the nonlinear and time dependent features of the ventilation systems for coal mines, a neural network method is applied to control the ventilator for coal mines in real time. The technical processes of co...According to the nonlinear and time dependent features of the ventilation systems for coal mines, a neural network method is applied to control the ventilator for coal mines in real time. The technical processes of coal mine ventilation system are introduced, and the principle of controlling a ventilation fan is also explained in detail. The artificial neutral network method is used to calculate the wind quantity needed by work spots in coal mine on the basis of the data collected by the system, including ventilation conditions, environmental temperatures, humidity, coal dust and the contents of all kinds of poisonous and harmful gases. Then the speed of ventilation fan is controlled according to the required wind which is determined by an overall integration of data. A neural network method is presented for overall optimized solution or the genetic algorithm of simulated annealing.展开更多
The ability of accurate and scalable mobile device recognition is critically important for mobile network operators and ISPs to understand their customers' behaviours and enhance their user experience.In this pape...The ability of accurate and scalable mobile device recognition is critically important for mobile network operators and ISPs to understand their customers' behaviours and enhance their user experience.In this paper,we propose a novel method for mobile device model recognition by using statistical information derived from large amounts of mobile network traffic data.Specifically,we create a Jaccardbased coefficient measure method to identify a proper keyword representing each mobile device model from massive unstructured textual HTTP access logs.To handle the large amount of traffic data generated from large mobile networks,this method is designed as a set of parallel algorithms,and is implemented through the MapReduce framework which is a distributed parallel programming model with proven low-cost and high-efficiency features.Evaluations using real data sets show that our method can accurately recognise mobile client models while meeting the scalability and producer-independency requirements of large mobile network operators.Results show that a 91.5% accuracy rate is achieved for recognising mobile client models from 2 billion records,which is dramatically higher than existing solutions.展开更多
The wide variety of smart embedded computing devices and their increasing number of applications in our daily life have created new op- portunities to acquire knowledge from the physical world anytime and anywhere, wh...The wide variety of smart embedded computing devices and their increasing number of applications in our daily life have created new op- portunities to acquire knowledge from the physical world anytime and anywhere, which is envisioned as the"Internet of Things" (IoT). Since a huge number of heterogeneous resources are brought in- to IoT, one of the main challenges is how to effi- ciently manage the increasing complexity of IoT in a scalable, flexNle, and autonomic way. Further- more, the emerging IoT applications will require collaborations among loosely coupled devices, which may reside in various locations of the Inter- net. In this paper, we propose a new IoT network management architecture based on cognitive net- work management technology and Service-Orien- ted Architecture to provide effective and efficient network management of loT.展开更多
To meet the increasing demand of wireless broadband applications in future 5G cellular networks, Device-to-Device(D2D) communications serve as a candidate paradigm to improve spectrum efficiency. Considering the chall...To meet the increasing demand of wireless broadband applications in future 5G cellular networks, Device-to-Device(D2D) communications serve as a candidate paradigm to improve spectrum efficiency. Considering the challenges after D2 D transmission is introduced for future cellular networks, this paper deals with mode selection and resource allocation issues related with D2 D communications. First, we propose a mode selection scheme which aims at guaranteeing the transmission of cellular users and also considering the potential interference. We analyze the condition under which D2 D underlay mode should be used. Second, we answer the question of "how to effectively reuse cellular resource once underlaying mode is adopted". We further present a resource allocation scheme that focuses on minimizing overall interference as well as a power control method to improve the performance of D2 D systems. Simulation results demonstrate that system parameters greatly affect the switching condition of mode selection and probability of choosing underlay mode. Furthermore, for D2 D underlaying scenario, the proposed resource allocation algorithm guarantees the transmission of cellular users with consideration of transmission requirements of D2 D users. Hence, the proposed scheme can achieve better user experience.展开更多
基金Supported by the Project of Philosophy and Social Sciences during the 12th Five-year Plan of Guangxi Zhuang Autonomous Region,China (11FGL031)~~
文摘The status and supporting policies of cold chain logistics equipment man- agement and control in China were described. The connotation of Internet of Things and its impact on cold chain logistics equipment management and control were ana- lyzed from external form to internal nature. Through introducing the value chain and relevant equipments of cold chain logistics, the correlation between the main technologies in Internet of Things and the common indices for cold chain logistics equipment management and control was analyzed in detail. The application values of Internet of Things technologies in cold chain logistics equipment management and control were illustrated, including the sample analysis on the application of radio-frequency identification (RFID). After the establishment of BSC performance evaluation index system of cold chain logistics equipment management and control, the optimization measures and suggestions on cold chain logistics equipment management and control under Internet of Things were put forward.
文摘Based on the system of electric power supply for flexible manufacturing systems (FMS), a study has been carried out on the intelligent safety examination, monitoring and maintenance of its running environment. On the basis of the specific feature of the power supply network of an FMS, real time monitoring system of the power supply network and the fault diagnostic expert system for the power equipment have been designed. This system can diagnose not only definite fault phenomena, but also fuzzy, uncertain fault phenomena as well. Fault diagnostic knowledge base for the power equipment has been founded hierarchy architecture model and the method of fault tree analysis. Feasibility of this system has been proved by computer simulation.
基金supported by the National Nature Science Foundation of China(NSFC 60622110,61471220,91538107,91638205)National Basic Research Project of China(973,2013CB329006),GY22016058
文摘With the popularity of smart handheld devices, mobile streaming video has multiplied the global network traffic in recent years. A huge concern of users' quality of experience(Qo E) has made rate adaptation methods very attractive. In this paper, we propose a two-phase rate adaptation strategy to improve users' real-time video Qo E. First, to measure and assess video Qo E, we provide a continuous Qo E prediction engine modeled by RNN recurrent neural network. Different from traditional Qo E models which consider the Qo E-aware factors separately or incompletely, our RNN-Qo E model accounts for three descriptive factors(video quality, rebuffering, and rate change) and reflects the impact of cognitive memory and recency. Besides, the video playing is separated into the initial startup phase and the steady playback phase, and we takes different optimization goals for each phase: the former aims at shortening the startup delay while the latter ameliorates the video quality and the rebufferings. Simulation results have shown that RNN-Qo E can follow the subjective Qo E quite well, and the proposed strategy can effectively reduce the occurrence of rebufferings caused by the mismatch between the requested video rates and the fluctuated throughput and attains standout performance on real-time Qo E compared with classical rate adaption methods.
基金supported by National Natural Science Foundation of China(No.U 1405254, 61472092)China Postdoctoral Science Foundation(No.2015M581101)National Science and Technology SupportingFoundation of China(No.2014BAH41B00)
文摘This paper proposes a new access architecture onmobile cloud,which introduces a middle layer sitting between mobile devices and their cloud infrastructure.This middle layer is composed of cloudlets which are deployed by cloud services providers,such as wireless network access points(APs),to improve the performance of mobile cloud servicesand be different from traditional mobile operator mode.Then based on this new architecture.we improve our previous(Attribute-basedencryption) ABE access control scheme on cloud for mobile cloud,which is proposed to offload the main amount of computations to the cloudlet as the function of cloud.Simulationresults demonstratethe new access control scheme takes into consideration response time constraints and network statusof access task execution,while satisfying certain network security for mobile cloud.
基金Project supported by the Second Stage of Brain Korea 21 ProjectsProject(10035236)supported by the IT_R&D Program of MKE/KEIT,Korea
文摘Though the WiMedia supports higher data rates than other WPAN technologies,a WiMedia device cannot reach other devices that are separated from it by more than 10 m,which is the typical limited transmission range of the WiMedia protocol.In this work,we propose a multi-hop QoS routing protocol to enable WiMedia devices to transmit real-time data to devices that are located out of the transmission range.The proposed routing protocol is a hybrid algorithm,which mixes the table-driven and on-demand routing algorithms,searching one or more routes according to the number of hops to a destination device.WiMedia MAC is potentially capable of learning the existence of neighbor devices by using a beacon frame.By utilizing the neighbors' information,all devices can create routing entries for devices within 2-hops periodically.For devices beyond the 2-hop range,the newly designed on-demand routing algorithm is applied to multi-hop routing.If a routing entry for a destination device is not listed in the routing table,the source device sends a request packet to 2-hop range devices which could be found in the routing table.Since every device maintains routing entries for 2-hop range devices in the routing table,the request packet is replied in advance before its arrival at the destination device.Also,to decide the optimal route for a destination device,the number of medium access slots(MASs),received signal strength indicator(RSSI)and hop count are utilized to establish a QoS-enabled routing table.We perform ns-2 simulation to investigate the performance of the proposed routing protocol with AODV and DSDV.The simulation results show that the proposed protocol has better throughput and lower overhead than other protocols.
文摘In this study, indoor air quality (IAQ) assessments were carried out in a screen printing facility. The air sampling was conducted in press department, including two different types of screen printing machines: semi-automatic and automatic. Air samples were collected and analyzed in situ for 4 times, once per 2 hours, during working time of 8 hours. Analysis of the experimental data showed that ambient ozone concentrations slowly increases with the increasing of TVOCs concentration and intensive use of UV lamps during automatic screen printing process. Therefore, the detected concentration levels of ozone and VOCs were compared with the Occupational Safety and Health Administration (OSHA) and Serbian Regulation. Comparison of the two mentioned standard regulations, the ozone concentrations in indoor printing air were from 0.83 to 8.1 and 2.4 to 16.2 times higher in the relation to the prescribed PEL and maximum allowed concentration (MAC) values, respectively, while the concentrations of particular VOCs were much below the PEL prescribed by the OSHA.
基金supported by the national 973 project of China under Grants 2013CB329104the Natural Science Foundation of China under Grants 61372124, 61427801+1 种基金the Natural Science Foundation of the Jiangsu Higher Education Institutions (Grant No.13KJB520029)the Jiangsu Province colleges and universities graduate students scientific research and innovation program CXZZ13_0477,NUPTSF(Grant No.NY214033)
文摘In Internet of Things(IoT), the devices or terminals are connected with each other, which can be very diverse over the wireless networks. Unfortunately, the current devices are not designed to communicate with the collocated devices which employ different communication technologies. Consequently, the communication between these devices will be realized only by using the gateway nodes. This will cause the inefficient use of wireless resources. Therefore, in this paper, a smart service system(SSS) architecture is proposed, which consists of smart service terminal(SST), and smart service network(SSN), to realize the Io T in a general environment with diverse communication networks, devices, and services. The proposed architecture has the following advantages: i) the devices in this architecture cover multiple types of terminals and sensor-actuator devices; ii) the communications network therein is a converged network, and will coordinate multiple kinds of existing and emerging networks. This converged network offers ubiquitous access for various sensors and terminals; iii) the architecture has services and applications covering all smart service areas. It also provides theadaptability to new services and applications. A SSS architecture-based smart campus system was developed and deployed. Evaluation experiments of the proposed smart campus system demonstrate the SSS's advantages over the existing counterparts, and verify the effectiveness of the proposed architecture.
文摘This research explored the organization's public relationship management practices in corporate blogs on the web. Content analyses of corporate blogs of large Korean firms over two years in a longitudinal design revealed that relationship management strategies of openness, positivity and sharing of tasks were featured relatively strongly, whereas networking, access, and assurances were enacted relatively weakly. Further, most Korean corporate blogs utilized a tightly controlled top-down strategy. In addition, the use level of relationship management strategy was tied to the kind of corporate blogging strategies, but not to the industry type of the firms. Although utilized the same social media device, corporate blogs enacted different purposes and relational management activities in different countries, indicating that corporate blogs are largely cultural and driven locally.
基金Supported by the National Natural Science Foundation of China (No. 60832009), the Natural Science Foundation of Beijing (No. 4102044) and the National Nature Science Foundation for Young Scholars of China (No. 61001115 ).
文摘In order to optimize handover target selection and achieve better handover performance in cellular relay networks under the long term evolution (LTE) system, a novel handover measurement and decision scheme based on cost function is proposed in the paper. The relay-enhanced network provides user equipment (UE) multiple handover choices from neighbor base stations or relays. This may result in different overhead, resource utility and traffic load which attaches importance to proper handover schemes. Compared with traditional handover measurement and decision schemes, the proposed scheme adopts reference signal receiving quality (RSRQ) in the measurement stage and uses a modified signal cost function considering signal overhead in different handover types and expected long-term throughput of UE. Besides, UE fairness and sector resource utilization are taken into account as well. Theory analysis and simulation results prove that the proposed scheme can enhance cell throughput, decrease handover delay and signal overhead, and improve UE fairness.
基金Project(2009C21001)supported by the Science and Technology Program of Zhejiang Province,China
文摘A novel 0.1% Pd-0.05% (mass fraction) Pt/stainless steel wire mesh catalyst was prepared for volatile organic compounds (VOCs) elimination. The catalyst was synthesized by stainless steel wire mesh as support and then treated by anodic oxidation technology to develop a porous membrane on the support. During the anodic oxidation process, various electrolytes were used to investigate the formation of porous membrane. And the catalytic performance of the catalysts was tested by using toluene and acetone combustion as model reaction. The temperatures of complete toluene and acetone conversion were decreased to 180℃ and 240 ℃, respectively. The morphologies of the stainless steel wire mesh supports and catalysts were characterized by means of scanning electron microscopy (SEM) and temperature-programmed reduction (TPR).
基金NationalKeyTechnologiesR&DProgram (No .2 0 0 1BA10 2C)
文摘This paper describes the design and development of a wireless LAN (WLAN) access point based on Bluetooth and uClinux. To make the best use of high-speed serial communication capability, several methods such as modifying baud-rate of serial port driver, utilizing buffer area and adding flow-control were adopted. After analysis of scheduling and interruption handling, modifying the timer's parameters was put forward as a method to control the timer interrupt. In this way, data throughput and system stability were enhanced. Meanwhile, migration of the Bluetooth protocol stack was detailed and some successful applications of LAN access point were presented.
基金supported by the National 863 projects of China(2014AA01A706)
文摘Device-to-Device(D2D) communication has been proposed to facilitate cellular network with system capacity(SC) and quality of service(QoS).We consider the design of link assignment(LA),channel allocation(CA)and power control(PC) in D2D-aided content delivery scenario for both user fairness(UF)and system throughput(ST) under QoS requirement.Due to the complexity of the problem,we decompose it into two components:CA is formulated from graph perspective to mitigate severe co-channel interference,which turns out to be the Max K-cut problem;LA and PC are jointly optimized to utilize the gain achieved from CA for supreme performance,and specifically,genetic algorithm(GA) is adopted to optimize LA,but when deriving the fitness of each chromosome,PC optimization will be involved.Thanks to numerical results,we elucidate the efficacy of our scheme.
文摘According to the nonlinear and time dependent features of the ventilation systems for coal mines, a neural network method is applied to control the ventilator for coal mines in real time. The technical processes of coal mine ventilation system are introduced, and the principle of controlling a ventilation fan is also explained in detail. The artificial neutral network method is used to calculate the wind quantity needed by work spots in coal mine on the basis of the data collected by the system, including ventilation conditions, environmental temperatures, humidity, coal dust and the contents of all kinds of poisonous and harmful gases. Then the speed of ventilation fan is controlled according to the required wind which is determined by an overall integration of data. A neural network method is presented for overall optimized solution or the genetic algorithm of simulated annealing.
基金supported in part by the National Natural Science Foundation of China under Grant No.61072061the National Science and Technology Major Projects under Grant No.2012ZX03002008the Fundamental Research Funds for the Central Universities under Grant No.2012RC0121
文摘The ability of accurate and scalable mobile device recognition is critically important for mobile network operators and ISPs to understand their customers' behaviours and enhance their user experience.In this paper,we propose a novel method for mobile device model recognition by using statistical information derived from large amounts of mobile network traffic data.Specifically,we create a Jaccardbased coefficient measure method to identify a proper keyword representing each mobile device model from massive unstructured textual HTTP access logs.To handle the large amount of traffic data generated from large mobile networks,this method is designed as a set of parallel algorithms,and is implemented through the MapReduce framework which is a distributed parallel programming model with proven low-cost and high-efficiency features.Evaluations using real data sets show that our method can accurately recognise mobile client models while meeting the scalability and producer-independency requirements of large mobile network operators.Results show that a 91.5% accuracy rate is achieved for recognising mobile client models from 2 billion records,which is dramatically higher than existing solutions.
基金supported by the National Sci.&Tech. Major Project of China(No.2010ZX03004-002)the National Natural Science Foundation of China(No.60972083)
文摘The wide variety of smart embedded computing devices and their increasing number of applications in our daily life have created new op- portunities to acquire knowledge from the physical world anytime and anywhere, which is envisioned as the"Internet of Things" (IoT). Since a huge number of heterogeneous resources are brought in- to IoT, one of the main challenges is how to effi- ciently manage the increasing complexity of IoT in a scalable, flexNle, and autonomic way. Further- more, the emerging IoT applications will require collaborations among loosely coupled devices, which may reside in various locations of the Inter- net. In this paper, we propose a new IoT network management architecture based on cognitive net- work management technology and Service-Orien- ted Architecture to provide effective and efficient network management of loT.
基金supported by the National Natural Science Foundation of China(No.61501371)National 863 High Tech R&D Program of China(project number:2014AA01A703)+1 种基金National Science and Technology Major Project of the Ministry of Science and Technology of China(project number:2014ZX03001025-006)The international Exchange and Cooperation Projects of Shaanxi Province(project number:2016KW-046)
文摘To meet the increasing demand of wireless broadband applications in future 5G cellular networks, Device-to-Device(D2D) communications serve as a candidate paradigm to improve spectrum efficiency. Considering the challenges after D2 D transmission is introduced for future cellular networks, this paper deals with mode selection and resource allocation issues related with D2 D communications. First, we propose a mode selection scheme which aims at guaranteeing the transmission of cellular users and also considering the potential interference. We analyze the condition under which D2 D underlay mode should be used. Second, we answer the question of "how to effectively reuse cellular resource once underlaying mode is adopted". We further present a resource allocation scheme that focuses on minimizing overall interference as well as a power control method to improve the performance of D2 D systems. Simulation results demonstrate that system parameters greatly affect the switching condition of mode selection and probability of choosing underlay mode. Furthermore, for D2 D underlaying scenario, the proposed resource allocation algorithm guarantees the transmission of cellular users with consideration of transmission requirements of D2 D users. Hence, the proposed scheme can achieve better user experience.