基于双矩形框标定的改进TLD算法

鉴于基于单个矩形框标定的Tracking-Learning-Detection(TLD)算法无法兼顾跟踪目标的"重点性"和"完整性",提出了一种基于双矩形框标定的改进算法。在标定整个目标区域的矩形框的基础上,算法在目标变化相对稳定的区域标定另一个矩形框,以指示跟踪的重点区域。在提取跟踪点时,采用分配权重的方法使重点区域产生更多的跟踪点,从而提高算法对局部变化的适应能力。实验表明,改进后的算法在跟踪局部保持稳定而其余部分有所变化的目标上有较高的性能提升;而对于不存在稳定局部区域的目标,跟踪效果没有明显改善。     

Theoretical analysis of a multiple-effect diffusion still producing highly concentrated seawater

A multiple-effect diffusion still producing highly concentrated seawater was theoretically analyzed taking variations of the boiling point elevation (BPE) into account. The still consists of a series of seawater-soaked wicks stuck on closely-spaced parallel plates with the first plate steam-heated at 100°C and the last plate cooled in 30°C ambient air. Evaporation from the wicks increases the BPE more rapidly at downstream distances closer to exits of evaporating areas, and this increase reduces evaporation flux significantly at downstream regions on the wicks. An 80% heat recovery from products of hot condensate and concentrate reduces the steam consumption by 46%. The steam consumption decreases more rapidly with an increasing number of wicks than does the production rate; thus, a lower steam consumption ratio is observed for the still having more wicks. Narrowing the gaps between the plates greatly increases the production rate with a slight decrease in the steam consumption ratio. The still with 19 wicks with 1 m by 2 m evaporating areas, 5 mm gaps and 80% heat recovery produces 12 kg distillate and 3.3 kg concentrate of 0.16 kg/kg-water concentration per 1 kg steam consumption with a 26.4 kg/h distillate production rate.     

Bezier曲线到AH-Bezier曲线的升阶算法

关于曲线升阶,已有的结论往往限于同类曲线之间。为了突破这一限制,考虑不同类曲线间的升阶,关注代数多项式空间中的Bezier曲线到代数双曲多项式空间中的AH-Bezier曲线的升阶。研究从基函数入手,利用Bezier和AH-Bezier共有的求导降阶的特点,结合矩阵分块的思想,先给出AH-Bezier基到Bernstein基的转换矩阵,进而推出控制顶点的升阶公式,最后给出升阶算法。结果表明,任意n次Bezier曲线可以通过该算法升到n＋3阶（等同于n＋2次）的AH-Bezier曲线。算法实现了Bezier到AH-B＆#233;zier曲线模型的精确转换。     

一种基于混合量子粒子群的快速运动目标跟踪算法研究

量子粒子群算法在优化过程中需要权衡局部探索性和全局开拓性,进化后期由于全局开拓能力的丧失使得种群多样性减少,设计了一种基于欧式距离的混合量子粒子群算法,通过计算粒子的种群多样性,当种群多样性低于阈值范围时加入基于欧式距离的种群划分策略划分子种群,从而保证获得全局最优解。利用标准测试函数验证提出的混合量子群算法有效性。提出了基于混合量子粒子群的Mean Shift算法(HQPSO Mean Shift)完成目标快速跟踪,克服传统Mean Shift算法的在跟踪快速移动目标时出现"跟丢"的问题。     

一种卡尔曼增益约束滤波算法

在滤波过程中,将卡尔曼增益结合约束条件,可以有效地提高滤波精度.论文推导了含有卡尔曼增益约束条件的代价函数,根据Karush-Kuhn-Tucker（KKT）最小化的一阶必要条件,使用高斯牛顿法求出约束卡尔曼增益的最优约束解.最后对具有约束条件的目标跟踪问题进行了仿真实验,结果表明该算法的跟踪精度要高于普通卡尔曼滤波算法.     

BackTrack5在网络渗透取证技术中的应用

本文对目前针对Linux平台下的BackTrack5进行阐述,内容涵盖敏感信息收集,漏洞信息收集,漏洞工具测试,账户特权升级等,笔者对在虚拟机环境下运行,下载BackTrack5,加载运行BackTrack5后需要进行网络配置加以说明,同时针对各种工具的常用命令及基本应用,实践后对其优缺点加以说明。     

跟踪微分器在生物雷达中的应用

在探测废墟下存活的人体时,生物雷达很难找到理想的参考信号对采集的信号进行处理.对已有生物雷达信号处理方法性能分析,提出了基于微分跟踪器（TD）的信号处理方法.该方法不需要理想的信号作为参考信号,且收敛性能和鲁棒性好、稳态误差小.MATLAB仿真分析证明了该算法应用于生物雷达信号处理的有效性.     

网络冗余技术在公司局域网的应用分析

随着SG186系统建设不断向企业的覆盖与延伸,信息网络的强健与否成为制约信息化系统应用的重要因素。本文通过对网络冗余技术的介绍,结合公司信息网络结构实际情况,通过应用实例分析,阐述如何合理使用网络冗余技术,确保信息网络的高可靠性。     

A quantitative feedback solution to the multivariable tracking error problem

This paper introduces a novel solution for the multi‐input multi‐output (MIMO) quantitative feedback theory control design problem with tracking error specifications. Looking for a minimum controller overdesign, the technique finds new controller quantitative feedback theory bounds based on necessary and sufficient conditions for the existence of suitable associated prefilter matrix elements. It improves previous approaches to the subject and includes (i) the possibility of a free selection of the nominal plant, (ii) a less conservative application of the Schwartz inequality to decisively reduce the potential controller overdesign, (iii) a methodology to design independently the elements of the prefilter matrix, and (iv) a scope of application to both sequential and nonsequential MIMO controller design methods. The benefits of the new control design technique are illustrated by means of two examples. The first one, a standard 2 × 2 MIMO problem, is provided for comparison purposes with previous approaches. The second example, included as a major control challenge, deals with a well‐known demanding distillation column benchmark problem. Copyright © 2013 John Wiley & Sons, Ltd.     

An embedding approach for the design of state‐feedback tracking controllers for references with jumps

We study the problem of designing state‐feedback controllers to track time‐varying state trajectories that may exhibit jumps. Both plants and controllers considered are modeled as hybrid dynamical systems, which are systems with both continuous and discrete dynamics, given in terms of a flow set, a flow map, a jump set, and a jump map. Using recently developed tools for the study of stability in hybrid systems, we recast the tracking problem as the task of asymptotically stabilizing a set, the tracking set, and derive conditions for the design of state‐feedback tracking controllers with the property that the jump times of the plant coincide with those of the given reference trajectories. The resulting tracking controllers guarantee that solutions of the plant starting close to the reference trajectory stay close to it and that the difference between each solution of the controlled plant and the reference trajectory converges to zero asymptotically. Constructive conditions for tracking control design in terms of LMIs are proposed for a class of hybrid systems with linear maps and input‐triggered jumps. The results are illustrated by various examples. Copyright © 2013 John Wiley & Sons, Ltd.