公共ATM网络的要求

本文介绍了ＡＴＭ（异步转移模式）在公共网络中的作用，ＡＴＭ在公共网络中的发展方向，最后着重讨论了公共ＡＴＭ网络的要求。     

电解铜箔产业发展趋势

随着技术的进步,电解铜箔在厚度上迅速向薄、超薄方向发展,THE、RCC、CAC等特殊性能铜箔需求比例快速 增加,以锂离子电池为代表的新应用领域正在形成。     

Dynamic-cost-reward connection admission control for maximizing system reward in 4G wireless multihop relaying networks

The 3GPP Long Term Evolution (LTE) Advanced and IEEE 802.16j specifications adopt the mobile multi-hop relaying (MMR) mechanism for enlarging service area and improving wireless transmission quality simultaneously. By deploying different types of Relay Stations (RSs), MMR can bring some advantages: (1) the signal fading and wireless interference of a single long wireless link is improved obviously; (2) the ranges of wireless access and relay area are extended, etc. MMR can offer a high data rate transmission for packet services and can increase system capacity. Note that MMR can be applied to the public transportation system, e.g., equipped a mobile RS on a high-speed train. A mobile RS handoff initializes a multiple handoff requests of different types of traffics. It becomes as a critical handoff issue in 4G MMR. Thus, the MMR handoff needs a new efficient Connection Admission Control (CAC) to guarantee qualities for various types of traffics and to increase system revenue. However, traditional CACs are difficult to fulfill the objectives. This paper thus proposes the Dynamic Cost-Reward-based (DCR) CAC that consists of two key mechanisms: (1) adopting a Markov decision process-based (MDP) cost function and (2) providing different reward functions for different types of nodes and various types of connection. Additionally, a mathematical analytical Markov chain is modeled for DCR. The simulation results are very close to the analysis results, which justifies the correctness of the analytical model. Numerical results demonstrate that DCA outperforms the compared CACs in the probabilities of new blocking, MS-handoff, and RS-handoff dropping, FRL, GoS, and system reward.     

基于AHP和MMTD的呼叫接纳控制方法AM-CAC

提出一种统一的呼叫接纳控制方法。应用层次分析过程(AHP)实现系统建模,根据网络运营目标,对于决策所依据的诸多准则之间的重要性关系进行定性分析和定量描述,从而确定各准则在决策中的影响力;应用中介真值程度度量(MMTD)方法统一量化各影响因素相对各准则的真值程度,通过配置合理参数,来适应异构网络在技术特性、性能目标上的差异。仿真结果表明,文中所提方法对于网络的运营目标和偏好具有很好的适应能力。     

Implementation of call admission control scheme in next generation mobile communication networks using particle swarm optimization and fuzzy logic systems

In the present and next generation wireless networks, cellular system remains the major method of telecommunication infrastructure. Since the characteristic of the resource constraint, call admission control is required to address the limited resource problem in wireless network. The call dropping probability and call blocking probability are the major performance metrics for quality of service (QoS) in wireless network. Many call admission control mechanisms have been proposed in the literature to decrease connection dropping probability for handoffs and new call blocking probability in cellular communications. In this paper, we proposed an adaptive call admission control and bandwidth reservation scheme using fuzzy logic control concept to reduce the forced termination probability of multimedia handoffs. Meanwhile, we adopt particle swarm optimization (PSO) technique to adjust the parameters of the membership functions in the proposed fuzzy logic systems. The simulation results show that the proposed scheme can achieve satisfactory performance when performance metrics are measured in terms of the forced termination probability for the handoffs, the call blocking probability for the new connections and bandwidth utilization.     

Drug self-assembly: A phenomenon at the nanometer scale with major impact in the structure–biological properties relationship and the treatment of disease

Under water-rich conditions, small amphiphilic and hydrophobic drug molecules self-assemble into supramolecular nanostructures. Thus, substantial modifications in their interaction with cellular structures and the ability to reach intracellular targets could happen. Additionally, drug aggregates could be more toxic than the non-aggregated counterparts, or vice versa. Moreover, since self-aggregation reduces the number of effective “monomeric” molecules that interact with the target, the drug potency could be underestimated. In other cases, the activity could be ascribed to the non-aggregated molecule while it stems from its aggregates. Thus, drug self-assembly could mislead from drug throughput screening assays to advanced preclinical and clinical trials. Finally, aggregates could serve as crystallization nuclei. The impact that this phenomenon has on the biological performance of active compounds, the inconsistent and often controversial nature of the published data and the need for recommendations/guidelines as preamble of more harmonized research protocols to characterize drug self-aggregation were main motivations for this review. First, the key molecular and environmental parameters governing drug self-aggregation, the main drug families for which this phenomenon and the methods used for its characterization are described. Then, promising nanotechnology platforms investigated to prevent/control it towards a more efficient drug development process are briefly discussed.     

一种保证远近比例公平的连接接纳控制策略

提出一种远近比例公平的接纳控制机制NFPF,通过控制距离基站较远和较近两类用户的接入概率,保证了两类用户连接接入的比例公平性.对NFPF机制进行了建模和性能分析.最后提出改进的远近效用比例公平接入控制算法UNFPF,实现了用户连接的效用公平性,并给出了简化的UNFPF算法,以降低运算复杂度.仿真表明,NFPF(UNFPF)机制能有效保证用户间的接入公平性,灵活性高,能够实现系统效用与接入公平的较好折衷.     

一种面向WiMAX的呼叫接纳控制算法

提出一种在WiMAX系统资源紧张时,使接纳率和资源利用率最大化的呼叫接纳控制CAC(Call Admission Control)算法。算法基于经济学概念,利用基尼系数(Gini Coefficient)给出了接纳控制模型,并用修正的sigmoid函数计算接纳概率。根据接纳概率决定是否接纳新到业务。仿真结果表明,算法与典型的截止优先权算法相比,在系统繁忙时系统接纳率和资源利用率都有较大提高。     

基于VCG机制的无线网络呼叫接入控制算法

提出一种基于VCG机制的无线网络呼叫接入控制（CAC）算法。该算法采用VCG机制调节用户需求,控制资源分配,以实现资源合理使用。CAC算法适合于无线接入网络中多业务服务、多优先级服务的情况。仿真结果表明,将VCG机制与CAC算法结合,能较好地改善无线网络性能,提高系统连接级的QoS。     

SUPANET的入网控制技术

本文以西南交通大学四川省网络通信技术重点实验室提出的“单物理层用户数据传输平面的体系结构”(SUPA)为背景,通过分析比较现存的各种接纳控制策略和算法,提出了适合SUPA的接纳控制策略和算法。