基于图像处理的晶体生长直径检测技术

针对单晶硅生长过程中的直径测量,提出一种“不在同一条直线上的三点确定圆”的直径测量算法.首先对获取到的单晶生长图像进行图像预处理,提取单晶体的边缘信息,然后基于“不在同一条直线上的三点确定圆”的原理,对部分“释热光环”提取特征点,从而获取硅单晶直径像素值,再通过量纲转化把直径像素值转化为长度值.试验表明,该算法获得的硅单晶直径的准确率满足直径检测系统的要求.     

基于uC/OS-II的数字电能表计量软件系统

首先介绍了将模拟小信号电能表与纯数字电能表的计量综合成一个系统以后的体系结构, 然后分析了在嵌入式实时操作系统uCOS-II环境下计量系统的实现: 包括任务的划分、任务间的通信以及数据的共享问题, 其中重点研究了任务间通信时数据的共享问题, 最后总结了任务间的总体通信情况, 为设计出高精度的数字电能表计量软件奠定了坚实的基础.     

Options analysis and knowledge management: Implications for theory and practice

Real options can be a powerful tool for quantifying the value of strategic and operational flexibility associated with uncertain IT investments. They also constitute a new way of thinking as to how knowledge management (KM) can be implemented and managed to maximize the upside potential while minimizing any downside risk. This paper explored how practitioners can incorporate options analysis into contemporary knowledge management. Options analysis is recognizing real options and then determines how they add value. The main issue here is to manage knowledge so that the theoretical option value is realized in practice. This paper developed a new metric, knowledge management performance index (KMPI), for evaluating the performance of a firm in its KM at any given point in time as follows: knowledge creation, knowledge conversion, knowledge circulation and knowledge completion. The higher the efficiency of the KM process, the higher the KMPI, thereby is enabling firms to become increasingly knowledgeable. To prove the contribution of the KMPI, a questionnaire survey was conducted among 121 firms listed on the Taiwan Stock Exchange Corporation (TSEC). This paper makes five important contributions: (1) it shows that if the KM process improves, the KMPI is enhanced. This finding is based on a survey of the questionnaires. As a result, the KMPI can effectively and efficiently represent the KM process; (2) it shows that when the KMPI increases, a company’s performance will be enhanced in five different areas This indicates a significant relationship between the KMPI and the company’s performance; (3) it also shows that the higher the KMPI, the higher the performance of the organization. This is especially valuable to any organization where knowledge is not being used optimally; (4) it provides an option analysis that may be helpful to managers for making the right decision in an uncertain environment; and (5) it presents the first application of the Black-Scholes model to use an actual business situation involving KM as its test bed. The results proved that the option pricing model can act as a measurement guideline for the entire knowledge of the whole company.     

A study of traffic, user behavior and pricing policies in a large campus network

Tsinghua University campus network is a large campus network in China, providing volume-based and flat-rate Internet access service for more than 31,000 students and staff. In order to better understand its traffic, user behavior and pricing policies to facilitate network planning and management, we collect a one-year-long flow-based traffic log and a 10-year-long user-based log at the boundary of this campus network, and then conduct an analysis study on these two data sets. In this paper, we first present characteristics of inbound traffic flows from the aspects of traffic prediction and inference. Then we analyze the geographical origins of incoming flows, and the result reveals that USA, Japan and Korea are the most important source countries of international traffic. Our user-based investigation shows that the properties of users have important influence on their behavior, e.g., major has stronger influence on users’ online time, while occupation has stronger influence on users’ international traffic volume. We also find that there are more and more users choosing flat rate pricing scheme instead of volume based pricing scheme, and these users tend to over-provision when they subscribe from tiered pricing options.     

Using RFID for the management of pharmaceutical inventory — system optimization and shrinkage control

Motivated by a case study at a radiology practice, we analyze the incremental benefits of RFID technology over barcodes for managing pharmaceutical inventories. Unlike barcode technology, RFID enables accurate real-time visibility, which in turn enables several process improvements. We analyze the impact of automatic counting and discuss the system redesign critical to optimizing the inventory policy and eliminating shrinkage. We show that continuous review is superior to periodic review whenever accurate real-time information is available at no additional cost. We explain how RFID-enabled strategies vary with inventory parameters and provide a cost-benefit analysis for the implementation of RFID for the radiology practice.     

具有测量数据丢失的离散不确定时滞系统鲁棒Kalman滤波

研究了具有测量数据丢失的离散不确定时滞系统鲁棒Kalman滤波问题, 其中时延存在于系统状态和观测值中. 模型的不确定性通过在系统矩阵中引入随机参数扰动来表示, 测量数据丢失现象则通过一个满足Bernoulli分布且统计特性已知的随机变量来描述. 基于最小方差估计准则, 利用射影性质和递归射影公式得到一个新的滤波器设计方法, 并且保证了滤波器的维数与原系统相等. 与传统的状态增广方法相比, 当时延比较大时, 该方法可以有效降低计算量. 最后, 给出一个仿真例子说明所提方法的有效性.     

基于不确定性度量的多特征融合跟踪

提出了一种新的基于特征不确定性度量的多特征融合跟踪算法. 首先, 针对粒子滤波跟踪算法中特征鉴别能力较弱且粒子分布相对分散时容易造成目标丢失的事实, 本文定义了一种新的特征不确定度量方法, 该度量可以在线调整不同类型特征对跟踪结果的贡献. 同时, 针对乘性和加性特征融合跟踪算法方法中存在的缺陷, 提出了一种自适应的多特征融合方法, 融合的结果既突出了状态后验分布中目标真实状态对应的峰值, 又对噪声不敏感, 从而提高了目标跟踪的鲁棒性. 各种场景下的实验结果比较表明: 新的融合跟踪算法比单特征跟踪、 乘性融合跟踪和加性融合跟踪有着更好的稳定性和鲁棒性.     

滑动频率估计算法在微波测量液位中的应用

在微波测量液位的系统中,正弦信号的频率估计是实现液位测量的关键.比较并分析了离散FFT变换的两种正弦信号频率估计方法:Rife比值法和三角形法,提出了一种滑动频率估计方法,通过实时确定比例因子,得到了滑动频谱校正算法.实验结果表明,该方法频率估计精度较高,估计性能优于单一的Rife法、三角形法,适合于低信噪比条件下的实...     

基于STM8的红外与超声波测距仪设计

介绍了一种基于STM8单片机的红外和超声波相结合的距离继电器的应用设计。阐述了该距离继电器的测距原理。经实际应用证明,该距离继电器的测量距离远大于10 m,克服了普通超声波测量距离只能达到5 m左右的问题,并且消除了测量的盲区。测量精度可以精确到1 cm,符合并超过实际应用要求。     

航测CCD预处理系统的设计与实现

设计了一个应用于航空摄影测量的CCD预处理系统.系统由相机数据处理和控制分系统组成.相机数据处理部分实现与记录系统和机上数传系统间的数据通信,要求对CCD相机送来的数据进行合成、压缩、缓存和视频编码.控制分系统实现与各系统之间的串口通信、温度控制以及电压转换.介绍了视频编码芯片和单片机通过I2C总线进行数据通信的原理和...