USB接口被广泛地应用在计算机外设接口地设计中 ,尤其是嵌入式系统和穿戴计算机系统 .为了减小系统的体积 ,提高系统的集成度 ,可以利用 System On Chip技术将 USB主机控制器集成在微处理器中 ,构成片上系统 ,这就需要自行设计 U SB主...USB接口被广泛地应用在计算机外设接口地设计中 ,尤其是嵌入式系统和穿戴计算机系统 .为了减小系统的体积 ,提高系统的集成度 ,可以利用 System On Chip技术将 USB主机控制器集成在微处理器中 ,构成片上系统 ,这就需要自行设计 U SB主机控制器的核 (Core) .本文系统地剖析了 U SB主机控制器的原理和结构 ,并针对 OHCI从系统级上给出了一个典型的 U展开更多
The conception of trusted network connection （TNC） is introduced, and the weakness of TNC to control user＇s action is analyzed. After this, the paper brings out a set of secure access and control model based on acc...The conception of trusted network connection （TNC） is introduced, and the weakness of TNC to control user＇s action is analyzed. After this, the paper brings out a set of secure access and control model based on access, authorization and control, and related authentication protocol. At last the security of this model is analyzed. The model can improve TNC＇s security of user control and authorization.展开更多
Objective:To evaluate the predatory potential of the Odonata nymph on freshwater snails that serve as intermediate hosts for Schistosoma species(Bulinus truncatus and Biomphalaria alexandrina).Methods:Observations on ...Objective:To evaluate the predatory potential of the Odonata nymph on freshwater snails that serve as intermediate hosts for Schistosoma species(Bulinus truncatus and Biomphalaria alexandrina).Methods:Observations on the searching,attacking and devouring of the two snail types with series of laboratory-based predation experiments,whose aims were to determine daily predation rate,differential predation,prey preference considering small-,mediumand large-sized snails were conducted.Results:Laboratory evaluation revealed that,the Odonata nymph could kill and consume the two intermediate hosts.The number of snails consumed differed according to the snail type,size and density.The times taken for searching and handling times were dependent on the snail size,type and satiation of the predator.The predation rate varied also with respect to snail type,size and density.This study also evaluated that Odonata nymphs consumed more Bulinus truncatus than Biomphalaria alexandrina per unit time,and that there may be a preference for smaller than larger snails.Conclusions:According to our observation,the predator,Hemianax ephippiger nymph may be a suitable biocontrol agent in connection with Schistosoma intermediate hosts.展开更多
Multiple wireless access technology has been embedded into a single mobile device as a fundamental feature, aiming to give end users ubiquitous access at any time. To allow the users to enjoy the ubiquitous connectivi...Multiple wireless access technology has been embedded into a single mobile device as a fundamental feature, aiming to give end users ubiquitous access at any time. To allow the users to enjoy the ubiquitous connectivity, the mobile device has to consume higher energy for the simultaneous activation of multiple wireless interface and the continuous connectivity. In addition, a seamless vertical handover between the access technologies is a mandatory requirement to insure the quality, reliability and continuity of real time services. In this paper, the continuity of real time services as well as energy saving for mobile devices has been taken into account. The conceptual idea is that whenever traffic rate is lower than a threshold it will be smoothly handed over to a low energy consumption technology, i.e., Bluetooth. When the traffic exceeds the limitation of Bluetooth bandwidth, it will be handed over to a wider bandwidth technology, i.e., Wi-Fi. In the considered scenarios, the technologies are not interconnected;hence, the vertical handover management must be fully controlled by the mobile devices. The performance of the system including energy saving and maintaining the continuity of real time services has been evaluated by direct measurements in a real testbed.展开更多
Objective: To evaluate the predatory capacity of the Odonata, Hemianax ephippiger nymph as a biocontrol agent for the freshwater snail Lymnaea natalensis, intermediate host of Fasciola gigantica. Methods: Observations...Objective: To evaluate the predatory capacity of the Odonata, Hemianax ephippiger nymph as a biocontrol agent for the freshwater snail Lymnaea natalensis, intermediate host of Fasciola gigantica. Methods: Observations on the searching, attacking and devouring of the snails with a series of laboratory-based predation experiments, whose aims were to determine daily predation rate, differential predation on small-, medium- and large-sized snails were carried out. Results: Laboratory evaluation revealed that, the Odonata nymph could kill and consume all three sizes of snails. Searching and handling time of the predator differed depending on snail size and predator vulnerability. The predation rate varied also with respect to snail size and density.Conclusions: Our observations suggested that the predator Hemianax ephippiger may be a suitable bio-control agent of Lymnaea natalensis snail population.展开更多
Observations were made on young nursery plants and apple orchards to record the coccinellid predators of Aphis pomi De Geer on apple plants in Himachal Pradesh which is main apple growing state of India. Nine species ...Observations were made on young nursery plants and apple orchards to record the coccinellid predators of Aphis pomi De Geer on apple plants in Himachal Pradesh which is main apple growing state of India. Nine species of lady bird beetles were observed feeding on green apple aphid, Aphis pomi De Geer on the apple nursery plants of Mashobra locality of Shimla district and Ner Chowk locality of Mandi district of Himachal Pradesh, India. On the basis of general observations, it was found that the larvae of beetle Harmonia dimidiata (F.), are very active to feed on the nymphs of green apple aphid. Therefore, it was considered worthwhile to investigate the biology and feeding potential of this beetle on green apple aphid from biological control point of view.展开更多
Abstract Low-angle faults include those occurring in thrust-nappe structures in a compressive setting and the detachment of metamorphic core complexes in an extensional setting. All low-angle faults have their own par...Abstract Low-angle faults include those occurring in thrust-nappe structures in a compressive setting and the detachment of metamorphic core complexes in an extensional setting. All low-angle faults have their own particularities. The low-angle fault plays an important role in controlling over some endogenetic metallic ore deposits. Based on studies of the Xiaoban gold deposit, Xinzhou gold deposit, and Longfengchang polymetallic ore deposit, and comparisons with other mines, the authors conclude the ore-controlling implications of low-angle faults as follows. (1) Because of high temperature and high pressure, as well as strong ductile deformation, the internal energy of the elements rises in the large-scale deep ductile low-angle faults, which causes the elements to activate and differentiate from the source rocks, forming ore-bearing hydrothermal solution, and bring mineralization to happen. (2) When rising from depths and flowing along the low-angle faults, the ore-bearing hydrothermal solution will alter and replace the tectonites in the fault zone. The rocks of the hanging side and the heading side differ in lithology, texture and structure, which results in changes or dissimilarities of the physical-chemical conditions. This destroys the balance of the hydrothermal solution system and causes the dissolved ore-forming elements to precipitate; as a result, a deposit is formed. Therefore, the meso-shallow ductile-brittle low-angle faults play the role of a geochemical interface in the process of mineralization. (3) Low-angle faults are often one of the important host structures.展开更多
文摘USB接口被广泛地应用在计算机外设接口地设计中 ,尤其是嵌入式系统和穿戴计算机系统 .为了减小系统的体积 ,提高系统的集成度 ,可以利用 System On Chip技术将 USB主机控制器集成在微处理器中 ,构成片上系统 ,这就需要自行设计 U SB主机控制器的核 (Core) .本文系统地剖析了 U SB主机控制器的原理和结构 ,并针对 OHCI从系统级上给出了一个典型的 U
基金Supported by Specialized Research Fund for theDoctoral Programof Higher Education of China (20050013011)
文摘The conception of trusted network connection （TNC） is introduced, and the weakness of TNC to control user＇s action is analyzed. After this, the paper brings out a set of secure access and control model based on access, authorization and control, and related authentication protocol. At last the security of this model is analyzed. The model can improve TNC＇s security of user control and authorization.
基金Supported by Theodor Bilharz Research Institute,Imbaba,Giza,Egypt(Grant No.94M)
文摘Objective:To evaluate the predatory potential of the Odonata nymph on freshwater snails that serve as intermediate hosts for Schistosoma species(Bulinus truncatus and Biomphalaria alexandrina).Methods:Observations on the searching,attacking and devouring of the two snail types with series of laboratory-based predation experiments,whose aims were to determine daily predation rate,differential predation,prey preference considering small-,mediumand large-sized snails were conducted.Results:Laboratory evaluation revealed that,the Odonata nymph could kill and consume the two intermediate hosts.The number of snails consumed differed according to the snail type,size and density.The times taken for searching and handling times were dependent on the snail size,type and satiation of the predator.The predation rate varied also with respect to snail type,size and density.This study also evaluated that Odonata nymphs consumed more Bulinus truncatus than Biomphalaria alexandrina per unit time,and that there may be a preference for smaller than larger snails.Conclusions:According to our observation,the predator,Hemianax ephippiger nymph may be a suitable biocontrol agent in connection with Schistosoma intermediate hosts.
文摘Multiple wireless access technology has been embedded into a single mobile device as a fundamental feature, aiming to give end users ubiquitous access at any time. To allow the users to enjoy the ubiquitous connectivity, the mobile device has to consume higher energy for the simultaneous activation of multiple wireless interface and the continuous connectivity. In addition, a seamless vertical handover between the access technologies is a mandatory requirement to insure the quality, reliability and continuity of real time services. In this paper, the continuity of real time services as well as energy saving for mobile devices has been taken into account. The conceptual idea is that whenever traffic rate is lower than a threshold it will be smoothly handed over to a low energy consumption technology, i.e., Bluetooth. When the traffic exceeds the limitation of Bluetooth bandwidth, it will be handed over to a wider bandwidth technology, i.e., Wi-Fi. In the considered scenarios, the technologies are not interconnected;hence, the vertical handover management must be fully controlled by the mobile devices. The performance of the system including energy saving and maintaining the continuity of real time services has been evaluated by direct measurements in a real testbed.
文摘Objective: To evaluate the predatory capacity of the Odonata, Hemianax ephippiger nymph as a biocontrol agent for the freshwater snail Lymnaea natalensis, intermediate host of Fasciola gigantica. Methods: Observations on the searching, attacking and devouring of the snails with a series of laboratory-based predation experiments, whose aims were to determine daily predation rate, differential predation on small-, medium- and large-sized snails were carried out. Results: Laboratory evaluation revealed that, the Odonata nymph could kill and consume all three sizes of snails. Searching and handling time of the predator differed depending on snail size and predator vulnerability. The predation rate varied also with respect to snail size and density.Conclusions: Our observations suggested that the predator Hemianax ephippiger may be a suitable bio-control agent of Lymnaea natalensis snail population.
文摘Observations were made on young nursery plants and apple orchards to record the coccinellid predators of Aphis pomi De Geer on apple plants in Himachal Pradesh which is main apple growing state of India. Nine species of lady bird beetles were observed feeding on green apple aphid, Aphis pomi De Geer on the apple nursery plants of Mashobra locality of Shimla district and Ner Chowk locality of Mandi district of Himachal Pradesh, India. On the basis of general observations, it was found that the larvae of beetle Harmonia dimidiata (F.), are very active to feed on the nymphs of green apple aphid. Therefore, it was considered worthwhile to investigate the biology and feeding potential of this beetle on green apple aphid from biological control point of view.
文摘Abstract Low-angle faults include those occurring in thrust-nappe structures in a compressive setting and the detachment of metamorphic core complexes in an extensional setting. All low-angle faults have their own particularities. The low-angle fault plays an important role in controlling over some endogenetic metallic ore deposits. Based on studies of the Xiaoban gold deposit, Xinzhou gold deposit, and Longfengchang polymetallic ore deposit, and comparisons with other mines, the authors conclude the ore-controlling implications of low-angle faults as follows. (1) Because of high temperature and high pressure, as well as strong ductile deformation, the internal energy of the elements rises in the large-scale deep ductile low-angle faults, which causes the elements to activate and differentiate from the source rocks, forming ore-bearing hydrothermal solution, and bring mineralization to happen. (2) When rising from depths and flowing along the low-angle faults, the ore-bearing hydrothermal solution will alter and replace the tectonites in the fault zone. The rocks of the hanging side and the heading side differ in lithology, texture and structure, which results in changes or dissimilarities of the physical-chemical conditions. This destroys the balance of the hydrothermal solution system and causes the dissolved ore-forming elements to precipitate; as a result, a deposit is formed. Therefore, the meso-shallow ductile-brittle low-angle faults play the role of a geochemical interface in the process of mineralization. (3) Low-angle faults are often one of the important host structures.
