居家环境下老年人夜间行走辅助照明研究

随着年龄增长,老年人起夜逐渐频繁,对空间的适应能力逐渐下降。为了保障老年人夜间行走安全,居家环境下的辅助照明系统亟待改善。首先通过对老年人夜间行走情况与其居住空间情况进行调研,总结辅助照明现状与夜间行走空间的基本情况。然后,基于3种空间原型与2种路径原型,依托于适老建筑实验室进行空间模拟实验研究,并对不同辅助照明的位置进行满意度评价与分析。最后,提出老年人夜间行走辅助照明位置建议,以期为适老化夜间行走辅助照明环境设计与改造提供依据,提高居家养老安全性与舒适性。     

基于时变信号模型和归一化格型陷波器的科氏流量计信号处理方法

采用具有跟踪频率变化能力的自适应归一化格型陷波器,对频率、幅值和相位均按照随机游动模型变化的科氏流量传感器信号进行滤波,以求得其频率;再采用自适应谱线增强器从含有噪声的数据中提取所需要的信号;然后采用具有重叠窗的滑动Goertzel算法计算两路信号之间的实时相位差,并通过频率和相位差计算时间差,求得质量流量。仿真结果表明该方法是有效的。     

A model of finite-step random walk with absorbent boundaries

This paper proposes a model of finite-step lattice random walk with absorbent boundaries. We address a problem of optimal stop for this model, which is defined as the absorbent boundary value with maximum profit. Compared with many existing optimal stop investigations in the random process, our study only considers the small-sample behaviour (i.e., small number of steps behaviour) and does not consider the limit behaviour of the walk. The optimal stop time is given based on classical probability computation. Since the small-sample is more practical and common than the large-sample in many real world problems, the result obtained in this paper may provide some useful guidelines for real applications associated with the finite-step random walk such as the stock market and gambling games.     

Design and interpretation of cell trajectory assays

Cell trajectory data are often reported in the experimental cell biology literature to distinguish between different types of cell migration. Unfortunately, there is no accepted protocol for designing or interpreting such experiments and this makes it difficult to quantitatively compare different published datasets and to understand how changes in experimental design influence our ability to interpret different experiments. Here, we use an individual-based mathematical model to simulate the key features of a cell trajectory experiment. This shows that our ability to correctly interpret trajectory data is extremely sensitive to the geometry and timing of the experiment, the degree of motility bias and the number of experimental replicates. We show that cell trajectory experiments produce data that are most reliable when the experiment is performed in a quasi-one-dimensional geometry with a large number of identically prepared experiments conducted over a relatively short time-interval rather than a few trajectories recorded over particularly long time-intervals.     

关于小车机器人直线行走的控制分析

分析机器人的直线行走功能，建立物理模型，运用数学原理进行计算，得出小车机器人运动状态和左右轮速度的关系。进而分析小车机器人的直线控制方法，在传统命令的控制效果上，采用光电编码盘对左右轮转速采样，并以PWM方式输出，通过闭环控制的PID算法，实现对机器人行走速度的及时调整。     

规则网络中的扩散和反应──MonteCarlo模拟研究（Ⅰ）规则网络中的扩散

建立了一个较简单的、能比较有效地研究规则网络中分子扩散的随机游动试验方法。并用这一方法考察了规则网络中随机孔道堵塞和均匀孔道堵塞对分子扩散的影响。     

广西向阳坪铀矿“打滑”地层绳索取心钻进存在问题与对策

通过绳索取心钻进金刚石钻头选型试验，介绍了广西资源县向阳坪铀矿区“打滑”地层中绳索取心钻进存在的问题及采取的技术措施。     

无线中继传感网络中异向散射信道的路径损耗特性

使用点渗流网格建模无线传播信道,使用酒徒行走模型建模电磁波在传感信道中的传播过程。酒徒经过k步后,得到某个扇区内取向角均匀分布的随机游走的平均行走距离。在此基础上,得到随机射线在传播空间给定位置的概率分布,最后使用随机射线方法得到了放大传送模式下传感网络的路径损耗模型。该模型中出现指数为1.75的距离r的对数函数形式,以及距离的线性项,该项作为新模型的修正项。     

应用随机轨道模型研究颗粒在通风管道内的沉积

本文采用欧拉-拉格朗日法模拟了纳米-微米级颗粒在竖直以及水平通风管道中的沉积.首先,采用常用的RNG κ-ε两方程模型得到了时均流场,采用单向耦合的随机轨道模型产生了脉动速度并模拟了流场一颗粒之间的作用.而后,针对RNG κ-ε两方程模型会过高估计在扩散区以及扩散-碰撞区颗粒沉积速度的问题,提出了简便的修正方法,并与文献中的经验公式以及试验数据进行了对比.结果表明,应用本文提出的修正方法可以极大地提高欧拉-拉格朗日法模拟颗粒沉积的准确度.     

Enabling Energy Efficient Sensory Data Collection Using Multiple Mobile Sink

Mobile sink is the challenging task for wireless sensor networks （WSNs）. In this paper we propose to design an efficient routing protocol for single mobile sink and multiple mobile sink for data gathering in WSN. In this process, a biased random walk method is used to determine the next position of the sink. Then, a rendezvous point selection with splitting tree technique is used to find the optimal data transmission path. If the sink moves within the range of the rendezvous point, it receives the gathered data and if moved out, it selects a relay node from its neighbours to relay packets from rendezvous point to the sink. Proposed algorithm reduces the signal overhead and improves the triangular routing problem. Here the sink acts as a vehicle and collect the data from the sensor. The results show that the proposed model effectively supports sink mobility with low overhead and delay when compared with Intelligent Agent-based Routing protocol （IAR） and also increases the reliability and delivery ratio when the number of sources increases.