Considering wireless sensor network characteristics,this paper uses network simulator,version2(NS-2)algorithm to improve Ad hoc on-demand distance vector(AODV)routing algorithm,so that it can be applied to wireless se...Considering wireless sensor network characteristics,this paper uses network simulator,version2(NS-2)algorithm to improve Ad hoc on-demand distance vector(AODV)routing algorithm,so that it can be applied to wireless sensor networks.After studying AODV routing protocol,a new algorithm called Must is brought up.This paper introduces the background and algorithm theory of Must,and discusses the details about how to implement Must algorithm.At last,using network simulator(NS-2),the performance of Must is evaluated and compared with that of AODV.Simulation results show that the network using Must algorithm has perfect performance.展开更多
AIM: To evaluate the effects of NS-398, a cyclooxygenase2 (COX-2) inhibitor, on the proliferation and apoptosis of HepG2 cells.METHODS: The effects of NS-398 on the proliferation of HepG2 cells were evaluated by MTT. ...AIM: To evaluate the effects of NS-398, a cyclooxygenase2 (COX-2) inhibitor, on the proliferation and apoptosis of HepG2 cells.METHODS: The effects of NS-398 on the proliferation of HepG2 cells were evaluated by MTT. DNA fragmentation gel analysis was used to analyze the apoptotic cells. DNA ploidy and apoptotic cell percentage were calculated by flow cytometry.The expression of COX-2 and Bcl-2 mRNA was identified by competitive RT-PCR. Furthermore, expression level of Bcl-2 was detected using Western blot in HepG2 after treated with NS-398.RESULTS: NS-398 inhibited cell proliferation and induced apoptosis of HepG2 cells in a concentration-dependent manner. DNA ploidy analysis showed that S phase cells were significantly decreased with increase of NS-398 concentration.The quiescent G0/G1 phase was accumulated with decrease of Bcl-2 mRNA. Whereas NS-398 had no effect on the expression of COX-2 mRNA, and no correlations were found between COX-2 mRNA and HepG2 cell proliferation and apoptosis induced by NS-398 (r = 0.056 and r= 0.119,respectively). Bcl-2 protein level was inhibited after treated with NS-398.CONCLUSION: NS-398 significantly inhibits the proliferation and induces apoptosis of HepG2 cells. Mechanisms involved may be accumulation of quiescent G0/G1 phase and decrease of Bcl-2 expression.展开更多
针对在8/16位低速处理器上实现传输控制协议(Transfer Control Protocol TCP)过于复杂的问题,通过对TCP协议进行简化,减轻了微处理器的运算负担,降低了对系统存储空间的要求,使得TCP协议能够在8/16位低速处理器上实现.嵌入式网络中大量...针对在8/16位低速处理器上实现传输控制协议(Transfer Control Protocol TCP)过于复杂的问题,通过对TCP协议进行简化,减轻了微处理器的运算负担,降低了对系统存储空间的要求,使得TCP协议能够在8/16位低速处理器上实现.嵌入式网络中大量使用长度很小的数据帧,使得网络带宽利用率极低,为此在协议中应用了Na-gle算法,减少了协议所需带宽,提高了协议的吞吐率.采用NS-2(Network Simulator-2)进行的仿真结果表明:该方案是有效的,现已经在普通8位处理器上实现,并通过了在多种宽带网络上进行的测试,在网络电能表中得到了实际应用.展开更多
The mechanisms of TCP’s retransmission and reset will result in redundant packets. These redundant packets are often sent unnecessarily to the user over a slow last-hop link delaying useful traffic. This is a problem...The mechanisms of TCP’s retransmission and reset will result in redundant packets. These redundant packets are often sent unnecessarily to the user over a slow last-hop link delaying useful traffic. This is a problem for wide-area wireless links, such as General Packet Radio Service (GPRS), because unnecessary transmissions waste already limited radio bandwidth, battery power at the mobile terminal and incurs monetary cost due to charging by data volume. The paper first describes a GPRS model, then discusses how to eliminate the redundant packets in GPRS network and presents the simulation results in Network Simulation 2 (NS 2). The more traffic is, the more the network can benefit. In heavy traffic, it can even get more than 30% improvement in throughput. Average delay and loss percent are also lowered.展开更多
Telecommunications and information technology rapidly migrate towards the Future Internet (FI) era, which is characterized by powerful and complex network infrastructures, advanced applications, services and content, ...Telecommunications and information technology rapidly migrate towards the Future Internet (FI) era, which is characterized by powerful and complex network infrastructures, advanced applications, services and content, efficient power management as well as extensions in the business model. One of the main application areas that find prosper ground in the FI era, is medicine. In particular, latest advances in medical sciences are reflected on their capability to approach previously past-cure diseases, as well as to prevent the appearance and evolution of unpleasant situations. Those advances are often derived from interdisciplinary solutions to complex medical problems, supported by communications and electronics, which target fast, reliable and stable solutions to problems that are demanding in terms of velocity and accuracy. The goal of this paper is to present intelligent, knowledge-based management functionality capable of supporting emergency medical applications. An indicative emergency medical scenario is provided, along with extensive simulation results using the Network Simulator-2 (NS-2), for evaluating the performance of the proposed functionality.展开更多
Integrating the power grid technology with renewable power generation technologies, Demand Response (DR) programs enabled by the Advanced Metering Infrastructure (AMI) were introduced into the power grid in the intere...Integrating the power grid technology with renewable power generation technologies, Demand Response (DR) programs enabled by the Advanced Metering Infrastructure (AMI) were introduced into the power grid in the interest of both utilities and residents. They help to achieve load balance and increase the grid reliability by encouraging residents to reduce their power usage during peak load periods in return for incentives. To automate this process, appliances, in-house sensors, and the AMI controller need to be networked together. In this paper, we compare mainstream network technologies applicable to home appliance control and propose a solution combining Power Line Communication (PLC) with wireless communication in smart homes for the purpose of energy saving. We extended NS-2, a popular network simulator, to model such combined network scenarios. Using a number of different routing strategies, we then model and evaluate the network performance of DR programs in smart homes in such a combined network.展开更多
文摘Considering wireless sensor network characteristics,this paper uses network simulator,version2(NS-2)algorithm to improve Ad hoc on-demand distance vector(AODV)routing algorithm,so that it can be applied to wireless sensor networks.After studying AODV routing protocol,a new algorithm called Must is brought up.This paper introduces the background and algorithm theory of Must,and discusses the details about how to implement Must algorithm.At last,using network simulator(NS-2),the performance of Must is evaluated and compared with that of AODV.Simulation results show that the network using Must algorithm has perfect performance.
文摘AIM: To evaluate the effects of NS-398, a cyclooxygenase2 (COX-2) inhibitor, on the proliferation and apoptosis of HepG2 cells.METHODS: The effects of NS-398 on the proliferation of HepG2 cells were evaluated by MTT. DNA fragmentation gel analysis was used to analyze the apoptotic cells. DNA ploidy and apoptotic cell percentage were calculated by flow cytometry.The expression of COX-2 and Bcl-2 mRNA was identified by competitive RT-PCR. Furthermore, expression level of Bcl-2 was detected using Western blot in HepG2 after treated with NS-398.RESULTS: NS-398 inhibited cell proliferation and induced apoptosis of HepG2 cells in a concentration-dependent manner. DNA ploidy analysis showed that S phase cells were significantly decreased with increase of NS-398 concentration.The quiescent G0/G1 phase was accumulated with decrease of Bcl-2 mRNA. Whereas NS-398 had no effect on the expression of COX-2 mRNA, and no correlations were found between COX-2 mRNA and HepG2 cell proliferation and apoptosis induced by NS-398 (r = 0.056 and r= 0.119,respectively). Bcl-2 protein level was inhibited after treated with NS-398.CONCLUSION: NS-398 significantly inhibits the proliferation and induces apoptosis of HepG2 cells. Mechanisms involved may be accumulation of quiescent G0/G1 phase and decrease of Bcl-2 expression.
文摘针对在8/16位低速处理器上实现传输控制协议(Transfer Control Protocol TCP)过于复杂的问题,通过对TCP协议进行简化,减轻了微处理器的运算负担,降低了对系统存储空间的要求,使得TCP协议能够在8/16位低速处理器上实现.嵌入式网络中大量使用长度很小的数据帧,使得网络带宽利用率极低,为此在协议中应用了Na-gle算法,减少了协议所需带宽,提高了协议的吞吐率.采用NS-2(Network Simulator-2)进行的仿真结果表明:该方案是有效的,现已经在普通8位处理器上实现,并通过了在多种宽带网络上进行的测试,在网络电能表中得到了实际应用.
文摘The mechanisms of TCP’s retransmission and reset will result in redundant packets. These redundant packets are often sent unnecessarily to the user over a slow last-hop link delaying useful traffic. This is a problem for wide-area wireless links, such as General Packet Radio Service (GPRS), because unnecessary transmissions waste already limited radio bandwidth, battery power at the mobile terminal and incurs monetary cost due to charging by data volume. The paper first describes a GPRS model, then discusses how to eliminate the redundant packets in GPRS network and presents the simulation results in Network Simulation 2 (NS 2). The more traffic is, the more the network can benefit. In heavy traffic, it can even get more than 30% improvement in throughput. Average delay and loss percent are also lowered.
文摘Telecommunications and information technology rapidly migrate towards the Future Internet (FI) era, which is characterized by powerful and complex network infrastructures, advanced applications, services and content, efficient power management as well as extensions in the business model. One of the main application areas that find prosper ground in the FI era, is medicine. In particular, latest advances in medical sciences are reflected on their capability to approach previously past-cure diseases, as well as to prevent the appearance and evolution of unpleasant situations. Those advances are often derived from interdisciplinary solutions to complex medical problems, supported by communications and electronics, which target fast, reliable and stable solutions to problems that are demanding in terms of velocity and accuracy. The goal of this paper is to present intelligent, knowledge-based management functionality capable of supporting emergency medical applications. An indicative emergency medical scenario is provided, along with extensive simulation results using the Network Simulator-2 (NS-2), for evaluating the performance of the proposed functionality.
文摘Integrating the power grid technology with renewable power generation technologies, Demand Response (DR) programs enabled by the Advanced Metering Infrastructure (AMI) were introduced into the power grid in the interest of both utilities and residents. They help to achieve load balance and increase the grid reliability by encouraging residents to reduce their power usage during peak load periods in return for incentives. To automate this process, appliances, in-house sensors, and the AMI controller need to be networked together. In this paper, we compare mainstream network technologies applicable to home appliance control and propose a solution combining Power Line Communication (PLC) with wireless communication in smart homes for the purpose of energy saving. We extended NS-2, a popular network simulator, to model such combined network scenarios. Using a number of different routing strategies, we then model and evaluate the network performance of DR programs in smart homes in such a combined network.
