A Distributed Power Allocation Scheme in Green Cognitive Radio Ad Hoc Networks

For the realization of green communications in cognitive radio ad hoc networks(CRAHNs), selfadaptive and efficient power allocation for secondary users(SUs) is essential. With the distributed and timevarying network topology, it needs to consider how to optimize the throughput and power consuming, avoid the interference to primary users(PUs) and other SUs, and pay attention to the convergence and fairness of the algorithm. In this study, this problem is modeled as a constraint optimization problem. Each SU would adjust its power and corresponding strategy with the goal of maximizing its throughput. By studying the interactions between SUs in power allocation and strategy selection, we introduce best-response dynamics game theory and prove the existence of Nash equilibrium(NE) point for performance analysis. We further design a fully distributed algorithm to make the SUs formulate their strategy based on their utility functions, the strategy and number of neighbors in local area. Compared with the water-filling(WF) algorithm, the proposed scheme can significantly increase convergent speed and average throughput, and decrease the power consuming of SUs.     

Research of Consistency Maintenance Mechanism in Real-Time Collaborative Multi-View Business Modeling

Real-time collaborative editing(RTCE)can support a group of people collaboratively work from distributed locations at the same time.However,consistency maintenance is one key challenge when different types of conflicts happen.Therefore a common synchronous mechanism is proposed to support consistency maintenance in the process of multi-view business modeling.Based on operation analysis on different views of models in the real-time collaborative editing system,detection of potential conflicts is realized by means of a decision-making tree.Then consistency maintenance provides a comprehensive and applicable conflicts detection and resolution for collaborative business modeling.Finally,a prototype of collaborative multi-view business modeling system is introduced to verify the approach.The point is that the mechanism proposes a comprehensive solution for collaborative multi-view business modeling.     

潜堤掩护港域波浪传播数值模拟

采用基于Boussinesq方程的平面二维波浪数学模型,将潜堤作为动边界处理,对潜堤掩护港域的波浪传播变形进行数值模拟研究。首先,采用Ohyama等的潜堤试验数据,就数学模型对人工潜堤上波浪传播变形问题的适用性进行验证探讨;其次,针对某渔港外部潜堤防护工程,采用数学模型进行波浪场推算,分析潜堤的消浪过程,同时将模拟得出的波浪透射系数与国内外经验公式计算值进行对比,结果表明该数值模拟方法是有效的。     

南京长江第四大桥北锚碇沉井不排水下沉施工关键技术

南京长江第四大桥北锚碇矩形沉井高52.8 m,共分11节,分4次接高下沉施工,其中第5～11节分3次采用不排水下沉施工,主要介绍北锚碇沉井不排水下沉施工所需设备配置、空气吸泥机吸泥工艺等关键技术。     

高等级公路沥青混凝土路面车辙病害现场调查及原因分析

通过对高等级公路沥青混凝土路面车辙病害的现场调查,发现了当前我国沥青混凝土路面车辙的主要形态和特点;结合室内试验和有限元分析,系统地探讨了半刚性基层沥青混凝土路面车辙产生的主要原因。     

耐波性试验数据的NARMAX理论分析

采用耐波性模型试验测量的波高时历作为系统的输入,应用NARMAX模型理论对某船的纵摇和垂荡时历进行了辨识和预报.结果表明,理论分析预报得到的纵摇和垂荡时历曲线和试验测试数据时历曲线吻合度较好,只在某些峰值处有出入;当考虑到纵摇和垂荡之间的耦合关系,并在预报二者之一时,将另外一个时历也作为输入,则预报结果比较理想.NARMAX模型系统识别理论用之于船舶耐波性试验数据分析,还有待于进一步考察.     

鳍结构对SWATH船纵向稳定性及运动性能的影响

针对保持SWATH船纵向运动稳定鳍的结构尺寸难以确定的特点，从实船对鳍的展长和弦长取值的约束条件出发，利用计算机仿真出SWATH船在40kn的航速范围内保持纵向运动稳定的鳍结构尺寸的变化范围，然后，从这一范围内确定出不同航速且具有一定运动性能要求的鳍尺寸变化范围。以此为基础仿真出了对应于不同航速SWATH船在静水中的升沉和纵摇运动性能指标的变化范围。结果表明，此方法直观、有效，能初步确定稳定鳍尺寸并分析静水中鳍尺寸对SWATH船运动性能影响。     

一种新的GPS整周模糊度快速解算方法

提出一种新的快速整周模糊度求解方法，新方法当需要增加观测值时，不需要使用新旧观测值一并计算，而仅需要补充由新观测值引起的残差变化量，减少计算时间，节省存贮空间，并通过构造极值条件和采用整数高斯变换措施，从而提高了整周模糊度的搜索速度，试验研究表明，新方法比其它方法求解速度更快，更有效。     

NURBS曲面与隐式曲面求交的计算机实现及应用

阐述了参数曲面与隐式曲面求交的算法原理，给出计算机实现方法及交点可能的分布示意图，将其应用于基于NURBS的船体曲面与任意平面的求交中，并针对船体曲面的特点指出应用过程中应注意的问题。     

电控共轨技术在海上油田电站原油发动机上的适应性研究

针对电控共轨技术的发展特性,结合原油发动机在海上油田电站的应用,对电控共轨技术应用于海上油田电站原油发动机上的技术对接及其适应性进行了研究.分析了电控共轨技术应用于海上油田电站原油发动机需要解决的问题.研究结果表明,随着能够适应原油发动机的快速电磁阀和新型智能传感器的研发和应用、共轨燃油压力波动控制和计算研究的突破,以及持续恒压反馈控制的进一步完善和对非电控共轨原油发动机转型改造技术的成熟,电控共轨技术在海上油田电站原油发动机上具有广阔的应用前景.