首页 | 官方网站   微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 125 毫秒
1.
As a key link in human-computer interaction, emotion recognition can enable robots to correctly perceive user emotions and provide dynamic and adjustable services according to the emotional needs of different users, which is the key to improve the cognitive level of robot service. Emotion recognition based on facial expression and electrocardiogram has numerous industrial applications. First, three-dimensional convolutional neural network deep learning architecture is utilized to extract the spa...  相似文献   

2.
1.About Technical Communication 1.1 What is technical communication? "Technical communication" refers to any kind of information related to technical products, software, or services.Therefore, technical communication stands not only for user manuals of technical consumer products, but it also includes the documentation of machines and entire plants, online help for any kind of software, service and repair handbooks, computer-based training, and technical information available online.  相似文献   

3.
This paper describes the core of an equipment management framework offering general functionality based on grid of things.The framework supports sensor,wireless network and intelligent control system based on services and service features.The framework is more generic than traditional hierarchical equipment management framework.It supports sensor,actuator and wireless networks.In the framework,techniques of spontaneous service provision,grid,scene-aware,semantic reasoning,and equipment service management are smoothly synthesized.It enables equipments in grid of things to interact automatically,provides semantic-integration equipment status awareness,and supports meta-service management based adaptability and scalability.  相似文献   

4.
Dye-sensitized solar cell (DSC) consists a combination of several different materials: photoanodes with nanoparticulated semiconductors, sensitizers, electrolytes and counter electrodes (CEs). Each materials performs specific task for the conversion of solar energy into electricity. The main function of CE is to transfer electrons to the redox electrolyte and regenerate iodide ion. The work of CE is mainly focused on the studies of the kinetic performance and stability of the traditional CEs to improve the overall efficiency of DSC, seeking novel design concepts or new materials. In this review, the development and research progress of different CE materials and their electrochemical performance, and the problems are discussed.  相似文献   

5.
Braking of the urban vehicles of public service wastes a large number of engine energy in the condition of starting and stopping frequently.Aiming at the problem,an electro-mechanical braking energy regeneration system was proposed which adopted a high-speed flywheel and a battery to recover the braking energy and achieve the secondary traction for the auxiliary start function.The system strategy was designed and the braking simulation was processed to validate its feasibility.The experiment results show that the system can effectively recover the braking energy,improve the starting performance of the city bus and it can be applied to the engineering.  相似文献   

6.
The Emergency Medical Service( EMS) system in China from service supply chain perspective is analyzed. Firstly,it reviews service supply chain researches in emergency medical service,and it is found that waiting time,safety,service integration and communication before the emergency surgery are the four indicators to measure the quality of emergency medical service. Secondly,the information barrier-inconsistent information flow-is prominent,which is between emergency in hospital and pre-hospital,after analyzing three different types of flows on service, information and logistics. Besides, comparing with Joint Commission International accreditation( JCI) standards for hospitals in USA,the requirements of service integration and communication in Chinese hospital accreditation are much lower. In the end,a Smart First Aid Information Center( SFAIC) model for first aid service is proposed. This model can be used to enhance information exchanges more effectively between first aid in-and pre-hospital. Moreover,it also shortens pre-surgery time and betters the communication and coordination between service sections. To put it in a nutshell,the improved medical service process can greatly increase emergency medical service quality.  相似文献   

7.
Nowadays energy saving and environmental protection are crucial issues in the international society. One of the best solutions for both issues is to improve energy efficiency. To improve energy efficiency, it is commonly recognized by both standards and energy sectors that Minimum Energy Performance Standards (MEPS) could play an important role . China and the USA, the top two energy consumption countries in the world, both have adopted MEPS program to address the problem of energy conservation and environmental protection. This paper analyzes and compares the two countries’ MEPS programs from a historical and legal context, examining the role of different stakeholders in the process, the outcomes by standards, and then makes some recommendations for both sides.  相似文献   

8.
The planning of wireless communication networks in underdeveloped countries is studied for landline telephone,fixed broadband wireless access and PLMN systems via investigation and discussion of the LDC networks’ characteristic,technology selection,deployment consideration,network configuring,civil work evaluation and investment estimation.An example is embedded all through providing a general model.  相似文献   

9.
Agricultural Bank of China Limited (ABC), as one of the major integrated financial service providers in China, is committed to developing itself into a leading commercial bank that caters to the needs of "agriculture, rural areas and farmers" and features the urban and rural linkage, international development and diverse services. Considering the  相似文献   

10.
正Building economy is an important symbol of the comprehensive economic strength, the modern industry system and cluster degree of service industry, also a key indicator of urban economic development. The standardization of building economy services is of great significance to help building enterprises to improve service quality, standardize the order of industrial development and promote the high-quality development of urban economy. This paper points out  相似文献   

11.
Lin  Y.-C. Lai  W.K. 《Communications, IET》2007,1(5):846-857
In infrastructure wireless networks, the wireless hop can be considered as another hop of the transmission path. With the rapid growth of wireless traffics, the future wireless network is expected to provide services for heterogeneous data traffics with different quality of service (QoS) requirements. Most proposed schemes do not have adaptive mechanisms to deal with the environment changes. In real situation, bandwidths, error rates and loss rates of wireless links vary frequently. We will base on the differentiated service model and propose a wireless differentiation (WD) scheme for user datagram protocol (UDP) flows and a wireless differentiation with prioritised ACK scheme for connections with transmission control protocol (TCP) flows. Both schemes provide QoS support for IEEE 802.11b and do not change the basic access mechanism of IEEE 802.11b.  相似文献   

12.
Despite the seemingly exponential growth of mobile and wireless communication, this same technology aims to offer uninterrupted access to different wireless systems like Radio Communication, Bluetooth, and Wi-Fi to achieve better network connection which in turn gives the best quality of service (QoS). Many analysts have established many handover decision systems (HDS) to enable assured continuous mobility between various radio access technologies. Unbroken mobility is one of the most significant problems considered in wireless communication networks. Each application needs a distinct QoS, so the network choice may shift appropriately. To achieve this objective and to choose the finest networks, it is important to select a best decision making algorithm that chooses the most effective network for every application that the user requires, dependent on QoS measures. Therefore, the main goal of the proposed system is to provide an enhanced vertical handover (VHO) decision making program by using a Multi-Criteria Fuzzy-Based algorithm to choose the best network. Enhanced Multi-Criteria algorithms and a Fuzzy-Based algorithm is implemented successfully for optimal network selection and also to minimize the probability of false handover. Furthermore, a double packet buffer is utilized to decrease the packet loss by 1.5% and to reduce the number of handovers up to 50% compared to the existing systems. In addition, the network setup has an optimized mobility management system to supervise the movement of the mobile nodes.  相似文献   

13.
Despite the planned installation and operations of the traditional IEEE 802.11 networks, they still experience degraded performance due to the number of inefficiencies. One of the main reasons is the received signal strength indicator (RSSI) association problem, in which the user remains connected to the access point (AP) unless the RSSI becomes too weak. In this paper, we propose a multi-criterion association (WiMA) scheme based on software defined networking (SDN) in Wi-Fi networks. An association solution based on multi-criterion such as AP load, RSSI, and channel occupancy is proposed to satisfy the quality of service (QoS). SDN having an overall view of the network takes the association and reassociation decisions making the handoffs smooth in throughput performance. To implement WiMA extensive simulations runs are carried out on Mininet-NS3-Wi-Fi network simulator. The performance evaluation shows that the WiMA significantly reduces the average number of retransmissions by 5%–30% and enhances the throughput by 20%–50%, hence maintaining user fairness and accommodating more wireless devices and traffic load in the network, when compared to traditional client-driven (CD) approach and state of the art Wi-Balance approach.  相似文献   

14.
Providing global connectivity with high speed and guaranteed quality at any place and any time is now becoming a reality due to the integration and co-ordination of different radio access technologies. The internetworking of existing networks with diverse characteristics has been considered attractive to meet the incredible development of interactive multimedia services and ever-growing demands of mobile users. Due to the diverse characteristics of heterogeneous networks, several challenges have to be addressed in terms of quality of service (QoS), mobility management and user preferences. To achieve this goal, an optimal network selection algorithm is needed to select the target network for maximizing the end user satisfaction. The existing works do not consider the integration of utility function with mobile terminal mobility characteristics to minimize ping-pong effects in the integrated networks. An integrated multicriteria network selection algorithm based on multiplicative utility function and residual residence time (RRT) estimation is proposed to keep the mobile users always best connected. Multiplicative weighted utility function considers network conditions, application QoS and user preferences to evaluate the available networks. In this paper, the proposed scheme is implemented with two mainstreams (pedestrian users and high-velocity users). For high-velocity users, RRT and adaptive residence time threshold are also considered to keep the probability of handover failures and unnecessary handovers within the limits. Monte-Carlo simulation results demonstrate that the proposed scheme outperforms against existing approaches.  相似文献   

15.
邱晶  张平 《高技术通讯》2005,15(6):14-18
研究了采用TDMA接入方式的无线分组网络上行信道时隙分配策略,基于移动台的QoS要求,提出了一种自适应时隙分配算法。利用服务曲线对移动台的QoS要求进行了建模。算法的目标是在尽量满足所有移动台Qos要求的基础上提高系统的上行吞吐量。在无法满足所有移动台QoS要求的情况下,使得移动台实际发送的数据与满足服务曲线要求之间的偏差最小。仿真结果表明:该算法能够在系统吞吐量和系统偏差之间进行折衷,从而有效地平衡上述两个目标。  相似文献   

16.
The authors present a hybrid automatic repeat request technique using adaptive Reed-Solomon (RS) codes with packet erasure. This technique suits the transport layer in tactical mobile wireless networks with type I encryption, where encryption erasures the entire Internet protocol packet. The novelty of the presented technique is the multifaceted optimisation of Reed-Solomon codes at the transport layer for delivery assurance, speed of service (SoS) and network throughput. With this technique, the transport layer in tactical networks can meet the stringent requirements of quality of service imposed by the tactical network user, even under adverse conditions. These requirements define a high level of reliability (delivery assurance), a specific SoS and optimum use of the limited bandwidth (BW) of the wireless network, where the probability of packet erasure can be very high. The provided probabilistic analysis shows that focusing on network throughput alone will result in violating SoS and delivery assurance requirements. On the other hand, focusing on SoS and delivery assurance requirements can result in poor network throughput. The multifaceted optimisation technique, which utilises hybrid ARQ for message delivery, is described using a homogeneous Markov chain.  相似文献   

17.
The performance of a new pointer-based medium-access control protocol that was designed to significantly improve the energy efficiency of user terminals in quality-of-service-enabled wireless local area networks was analysed. The new protocol, pointer- controlled slot allocation and resynchronisation protocol (PCSARe), is based on the hybrid coordination function-controlled channel access mode of the IEEE 802.11e standard. PCSARe reduces energy consumption by removing the need for power-saving stations to remain awake for channel listening. Discrete event network simulations were performed to compare the performance of PCSARe with the non-automatic power save delivery (APSD) and scheduled-APSD power- saving modes of IEEE 802.11e. The simulation results show a demonstrable improvement in energy efficiency without significant reduction in performance when using PCSARe. For a wireless network consisting of an access point and eight stations in power-saving mode, the energy saving was up to 39% when using PCSARe instead of IEEE 802.11e non-APSD. The results also show that PCSARe offers significantly reduced uplink access delay over IEEE 802.11e non-APSD, while modestly improving the uplink throughput. Furthermore, although both had the same energy consumption, PCSARe gave a 25% reduction in downlink access delay compared with IEEE 802.11e S-APSD.  相似文献   

18.
Mobile ad hoc networks (MANETs) are unpredictable by nature. Providing any kind of reliability for quality of service (QoS) in such networks is challenging. Quantifying available resources accurately, avoiding interference with ongoing QoS traffic and adapting to QoS violations caused by nodes' mobility are the main concerns for the design of an efficient admission control protocol in MANETs. Adaptive admission control (AAC), a novel admission control protocol which uses robust and accurate resource estimation and prediction techniques for relevant admission decisions has been proposed. Furthermore, AAC uses statistical QoS provision to counteract the QoS threatening mobility. Through simulations, we show that our proposed scheme outperforms existing approaches in terms of correctness and overall performance.  相似文献   

19.
Genetic algorithms (GAs) and simulated annealing (SA) have emerged as leading methods for search and optimization problems in heterogeneous wireless networks. In this paradigm, various access technologies need to be interconnected; thus, vertical handovers are necessary for seamless mobility. In this paper, the hybrid algorithm for real-time vertical handover using different objective functions has been presented to find the optimal network to connect with a good quality of service in accordance with the user’s preferences. As it is, the characteristics of the current mobile devices recommend using fast and efficient algorithms to provide solutions near to real-time. These constraints have moved us to develop intelligent algorithms that avoid slow and massive computations. This was to, specifically, solve two major problems in GA optimization, i.e. premature convergence and slow convergence rate, and the facilitation of simulated annealing in the merging populations phase of the search. The hybrid algorithm was expected to improve on the pure GA in two ways, i.e., improved solutions for a given number of evaluations, and more stability over many runs. This paper compares the formulation and results of four recent optimization algorithms: artificial bee colony (ABC), genetic algorithm (GA), differential evolution (DE), and particle swarm optimization (PSO). Moreover, a cost function is used to sustain the desired QoS during the transition between networks, which is measured in terms of the bandwidth, BER, ABR, SNR, and monetary cost. Simulation results indicated that choosing the SA rules would minimize the cost function and the GA–SA algorithm could decrease the number of unnecessary handovers, and thereby prevent the ‘Ping-Pong’ effect.  相似文献   

20.
一种支持多跳无线网QoS业务的MAC层接入协议   总被引:1,自引:0,他引:1  
周滨  郭伟  任智 《中国测试技术》2006,32(2):100-103
提供一定的服务质量保证(QoS)是多跳无线网络研究中的热点和难点,本文基于TDMA/FDMA机制提出了一种支持多信道多跳无线网络话音级QoS业务的MAC层接入协议RA/SRN。该协议以RBRP协议思想为基础,针对无线信道中隐藏、暴露终端造成的信道利用率降低和分组冲突问题进行改进设计,减小了信道冲突概率,提高了信道利用率,降低了信道接入时延,为网络层QoS路由协议提供了良好的支持。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司    京ICP备09084417号-23

京公网安备 11010802026262号