Not only does the multi-media technology in teaching help students arouse curiosity and draw their attention,but also it makes students enhance their language skills and master knowledge.It makes English teaching smooth.
The demand for the telecommunication services,such as IP telephony,has increased dramatically during the COVID-19 pandemic lockdown.IP tele-phony should be enhanced to provide the expected quality.One of the issues th...The demand for the telecommunication services,such as IP telephony,has increased dramatically during the COVID-19 pandemic lockdown.IP tele-phony should be enhanced to provide the expected quality.One of the issues that should be investigated in IP telephony is bandwidth utilization.IP telephony pro-duces very small speech samples attached to a large packet header.The header of the IP telephony consumes a considerable share of the bandwidth allotted to the IP telephony.This wastes the network's bandwidth and influences the IP telephony quality.This paper proposes a mechanism(called Smallerize)that reduces the bandwidth consumed by both the speech sample and the header.This is achieved by assembling numerous IP telephony packets in one header and use the header'sfields to carry the speech sample.Several metrics have been used to measure the achievement Smallerize mechanism.The number of calls has been increased by 245.1%compared to the typical mechanism.The bandwidth saving has also reached 68%with the G.28 codec.Therefore,Smallerize is a possible mechanism to enhance bandwidth utilization of the IP telephony.展开更多
Typical multidisciplinary design optimization（MDO） has gradually been proposed to balance performances of lightweight, noise, vibration and harshness（NVH） and safety for instrument panel（IP） structure in the aut...Typical multidisciplinary design optimization（MDO） has gradually been proposed to balance performances of lightweight, noise, vibration and harshness（NVH） and safety for instrument panel（IP） structure in the automotive development. Nevertheless, plastic constitutive relation of Polypropylene（PP） under different strain rates, has not been taken into consideration in current reliability-based and collaborative IP MDO design. In this paper, based on tensile test under different strain rates, the constitutive relation of Polypropylene material is studied. Impact simulation tests for head and knee bolster are carried out to meet the regulation of FMVSS 201 and FMVSS 208, respectively. NVH analysis is performed to obtain mainly the natural frequencies and corresponding mode shapes, while the crashworthiness analysis is employed to examine the crash behavior of IP structure. With the consideration of lightweight, NVH, head and knee bolster impact performance, design of experiment（DOE）, response surface model（RSM）, and collaborative optimization（CO） are applied to realize the determined and reliability-based optimizations, respectively. Furthermore, based on multi-objective genetic algorithm（MOGA）, the optimal Pareto sets are completed to solve the multi-objective optimization（MOO） problem. The proposed research ensures the smoothness of Pareto set, enhances the ability of engineers to make a comprehensive decision about multi-objectives and choose the optimal design, and improves the quality and efficiency of MDO.展开更多
Water resource allocation was defined as an input-output question in this paper, and a preliminary input-output index system was set up. Then GEM （group eigenvalue method）-MAUE （multi-attribute utility theory） mod...Water resource allocation was defined as an input-output question in this paper, and a preliminary input-output index system was set up. Then GEM （group eigenvalue method）-MAUE （multi-attribute utility theory） model was applied to evaluate relative efficiency of water resource allocation plans. This model determined weights of indicators by GEM, and assessed the allocation schemes by MAUE. Compared with DEA （Data Envelopment Analysis） or ANN （Artificial Neural Networks）, the mode was more applicable in some cases where decision-makers had preference for certain indicators展开更多
As more and more sophisticated medical equipment being purchased by hospi-tals,the selection is becoming an increasingly complex and important process.Usu-ally there are three steps in the selection process: planning,...As more and more sophisticated medical equipment being purchased by hospi-tals,the selection is becoming an increasingly complex and important process.Usu-ally there are three steps in the selection process: planning,feasibility and model se-lection evaluation.Model selection evalution is the most complex stage.The consid-展开更多
Shortages in water resources and the fragile ecosystem by coal-mine water affect the Yulin coal-mine base in northwest China, so taking coal-mine water into account is an important issue for the sustainable management...Shortages in water resources and the fragile ecosystem by coal-mine water affect the Yulin coal-mine base in northwest China, so taking coal-mine water into account is an important issue for the sustainable management of water resources. This paper aims to explore how the Yulin coal-mine base can improve its conjunctive utilization of water resources. Integrated utilization is proposed by establishing a multi-objective, multi-water-source, optimal-allocation model;setting up an integrated information platform;and giving very useful measures and policy suggestions to the local government. Finally, this research can also serve as an example of integrated water utilization for other energy bases.展开更多
In the internet protocol（IP） over multi-granular optical switch network （IP/MG-OXC）, the network node is a typical multilayer switch comprising several layers, the IP packet switching （PXC） layer, wavelength swi...In the internet protocol（IP） over multi-granular optical switch network （IP/MG-OXC）, the network node is a typical multilayer switch comprising several layers, the IP packet switching （PXC） layer, wavelength switching （WXC） layer and fiber switching （FXC） layer. This network is capable of both IP layer grooming and wavelength grooming in a hierarchical manner. Resource provisioning in the multi-granular network paradigm is called hierarchical grooming problem. An integer linear programming （ILP） model is proposed to formulate the problem. An iterative heuristic approach is developed for solving the problem in large networks. Case study shows that IP/MG-OXC network is much more extendible and can significantly save the overall network cost as compared with IP over wavelength division multiplexing network.展开更多
面对广电IP数据网固移融合、云网协同和多业务融合承载的发展趋势,本文提出了省域广电IP骨干网建设发展的目标架构和组网设计、路由组织、业务承载等建设内容,借助SRv6原生隧道实现了IPv6单栈部署,通过SRv6 TE policy+FlexE提供业务差...面对广电IP数据网固移融合、云网协同和多业务融合承载的发展趋势,本文提出了省域广电IP骨干网建设发展的目标架构和组网设计、路由组织、业务承载等建设内容,借助SRv6原生隧道实现了IPv6单栈部署,通过SRv6 TE policy+FlexE提供业务差异化承载,引入SDN控制器和Telemetry、iFIT技术大幅提升全程全网运维管理和服务保障能力。展开更多
In this paper,several currently existed Mobility Management Schemes of Mobile IP are simply analyzed,and so does the network structure of multi-tier cellular which nowadays is easily seen. Then we propose a few promo-...In this paper,several currently existed Mobility Management Schemes of Mobile IP are simply analyzed,and so does the network structure of multi-tier cellular which nowadays is easily seen. Then we propose a few promo-tions on the strategies of mobility management when realizing mobile IP in multi-tier cellular network structure. Thekey of the promotions is that the required type of cell for a MN is determined based on the classification of its mobilitypattern. Consequently,the capacity of system may be increased while the frequency of handoff is decreased.展开更多
文摘Not only does the multi-media technology in teaching help students arouse curiosity and draw their attention,but also it makes students enhance their language skills and master knowledge.It makes English teaching smooth.
文摘The demand for the telecommunication services,such as IP telephony,has increased dramatically during the COVID-19 pandemic lockdown.IP tele-phony should be enhanced to provide the expected quality.One of the issues that should be investigated in IP telephony is bandwidth utilization.IP telephony pro-duces very small speech samples attached to a large packet header.The header of the IP telephony consumes a considerable share of the bandwidth allotted to the IP telephony.This wastes the network's bandwidth and influences the IP telephony quality.This paper proposes a mechanism(called Smallerize)that reduces the bandwidth consumed by both the speech sample and the header.This is achieved by assembling numerous IP telephony packets in one header and use the header'sfields to carry the speech sample.Several metrics have been used to measure the achievement Smallerize mechanism.The number of calls has been increased by 245.1%compared to the typical mechanism.The bandwidth saving has also reached 68%with the G.28 codec.Therefore,Smallerize is a possible mechanism to enhance bandwidth utilization of the IP telephony.
基金supported by National Hi-tech Research and Development Program of China(863 Program, Grant No. 2007AA04Z132)National Natural Science Foundation of China(Grant No. 51175379)
文摘Typical multidisciplinary design optimization（MDO） has gradually been proposed to balance performances of lightweight, noise, vibration and harshness（NVH） and safety for instrument panel（IP） structure in the automotive development. Nevertheless, plastic constitutive relation of Polypropylene（PP） under different strain rates, has not been taken into consideration in current reliability-based and collaborative IP MDO design. In this paper, based on tensile test under different strain rates, the constitutive relation of Polypropylene material is studied. Impact simulation tests for head and knee bolster are carried out to meet the regulation of FMVSS 201 and FMVSS 208, respectively. NVH analysis is performed to obtain mainly the natural frequencies and corresponding mode shapes, while the crashworthiness analysis is employed to examine the crash behavior of IP structure. With the consideration of lightweight, NVH, head and knee bolster impact performance, design of experiment（DOE）, response surface model（RSM）, and collaborative optimization（CO） are applied to realize the determined and reliability-based optimizations, respectively. Furthermore, based on multi-objective genetic algorithm（MOGA）, the optimal Pareto sets are completed to solve the multi-objective optimization（MOO） problem. The proposed research ensures the smoothness of Pareto set, enhances the ability of engineers to make a comprehensive decision about multi-objectives and choose the optimal design, and improves the quality and efficiency of MDO.
文摘Water resource allocation was defined as an input-output question in this paper, and a preliminary input-output index system was set up. Then GEM （group eigenvalue method）-MAUE （multi-attribute utility theory） model was applied to evaluate relative efficiency of water resource allocation plans. This model determined weights of indicators by GEM, and assessed the allocation schemes by MAUE. Compared with DEA （Data Envelopment Analysis） or ANN （Artificial Neural Networks）, the mode was more applicable in some cases where decision-makers had preference for certain indicators
文摘As more and more sophisticated medical equipment being purchased by hospi-tals,the selection is becoming an increasingly complex and important process.Usu-ally there are three steps in the selection process: planning,feasibility and model se-lection evaluation.Model selection evalution is the most complex stage.The consid-
文摘Shortages in water resources and the fragile ecosystem by coal-mine water affect the Yulin coal-mine base in northwest China, so taking coal-mine water into account is an important issue for the sustainable management of water resources. This paper aims to explore how the Yulin coal-mine base can improve its conjunctive utilization of water resources. Integrated utilization is proposed by establishing a multi-objective, multi-water-source, optimal-allocation model;setting up an integrated information platform;and giving very useful measures and policy suggestions to the local government. Finally, this research can also serve as an example of integrated water utilization for other energy bases.
基金Sponsored by Agency for Singapore Technology and Advance Research(RGM01/16)
文摘In the internet protocol（IP） over multi-granular optical switch network （IP/MG-OXC）, the network node is a typical multilayer switch comprising several layers, the IP packet switching （PXC） layer, wavelength switching （WXC） layer and fiber switching （FXC） layer. This network is capable of both IP layer grooming and wavelength grooming in a hierarchical manner. Resource provisioning in the multi-granular network paradigm is called hierarchical grooming problem. An integer linear programming （ILP） model is proposed to formulate the problem. An iterative heuristic approach is developed for solving the problem in large networks. Case study shows that IP/MG-OXC network is much more extendible and can significantly save the overall network cost as compared with IP over wavelength division multiplexing network.
文摘面对广电IP数据网固移融合、云网协同和多业务融合承载的发展趋势,本文提出了省域广电IP骨干网建设发展的目标架构和组网设计、路由组织、业务承载等建设内容,借助SRv6原生隧道实现了IPv6单栈部署,通过SRv6 TE policy+FlexE提供业务差异化承载,引入SDN控制器和Telemetry、iFIT技术大幅提升全程全网运维管理和服务保障能力。
文摘In this paper,several currently existed Mobility Management Schemes of Mobile IP are simply analyzed,and so does the network structure of multi-tier cellular which nowadays is easily seen. Then we propose a few promo-tions on the strategies of mobility management when realizing mobile IP in multi-tier cellular network structure. Thekey of the promotions is that the required type of cell for a MN is determined based on the classification of its mobilitypattern. Consequently,the capacity of system may be increased while the frequency of handoff is decreased.
