Real-time approximation of molecular interaction interfaces based on hierarchical space decomposition

The interaction interface between two molecules can be represented as a bisector surface equidistant from the two sets of spheres of varying radii representing atoms. We recursively divide a box containing both sphere-sets into uniform pairs of sub-boxes. The distance from each new box to each sphere-set is conservatively approximated by an interval, and the number of sphere-box computations is greatly reduced by pre-partitioning each sphere-set using a kd-tree. The subdivision terminates at a specified resolution, creating a box partition (BP) tree. A piecewise linear approximation of the bisector surface is then obtained by traversing the leaves of the BP tree and connecting points equidistant from the sphere-sets. In 124 experiments with up to 16,728 spheres, a bisector surface with a resolution of 1/2⁴ of the original bounding box was obtained in 28.8 ms on average.     

基于nRF24LE1的智能双向汽车遥控系统

基于射频系统芯片nRF24LE1,设计了一种具有双向通信功能的汽车遥控器和车锁控制系统,重点研究了系统的结构和软、硬件设计。遥控器不仅可以发送控制信息,还可以接收车锁的反馈信息,比目前普遍使用的单向遥控器功能强大。同时在车锁部分,增加了GSM模块,实现GSM网络与遥控器的双重控制,更能确保汽车的安全。     

基于ATmega16L的PID温控系统设计

详细介绍了基于ATmega16L为核心的温度控制系统设计,传感器用Pt100并以PID算法进行温控,上位机PC与ATmega16L单片机之间通过串口通信。可对工作现场实时监控、温度曲线显示。参数设定后下位机可独立进行相应的PID控制运算控制PWM,来控制调节温度。应用于样品烘制的温度控制,具有成本低精度高、易于维护的特点。     

A characterization of span program size and improved lower bounds for monotone span programs

We give a characterization of span program size by a combinatorial-algebraic measure. The measure we consider is a generalization of a measure on covers which has been used to prove lower bounds on formula size and has also been studied with respect to communication complexity.?In the monotone case our new methods yield lower bounds for the monotone span program complexity of explicit Boolean functions in n variables over arbitrary fields, improving the previous lower bounds on monotone span program size. Our characterization of span program size implies that any matrix with superpolynomial separation between its rank and cover number can be used to obtain superpolynomial lower bounds on monotone span program size. We also identify a property of bipartite graphs that is suficient for constructing Boolean functions with large monotone span program complexity. Received: September 30, 2000.     

基于Linux的通用视频音频采集系统的设计与实现

该文阐述了在Linux下,利用V4L以及ALSA,在普通PC上组建视频音频采集系统以及远程传输的方法。     

Bluetooth协议栈一致性测试

Bluetooth协议栈实现的一致性测试是保证不同厂商产品之间互连与互操作的基础。文章基于OSI协议一致性测试标准进行了Bluetooth协议一致性测试研究和实际测试,并以L2CAP层协议为例介绍了一致性测试的方法、结构、测试集的设计生成与完备性分析。     

Convergence Results of One-Leg and Linear Multistep Methods for Multiply Stiff Singular Perturbation Problems

One-leg methods and linear multistep methods are two class of important numerical methods applied to stiff initial value problems of ordinary differential equations. The purpose of this paper is to present some convergence results of A-stable one-leg and linear multistep methods for one-parameter multiply stiff singular perturbation problems and their corresponding reduced problems which are a class of stiff differential-algebraic equations. Received April 14, 2000; revised June 30, 2000     

A New Well-Solvable Class of PNS Problems

A manufacturing system consists of operating units which convert their input materials into their output materials. In the problem of designing a process network, we have to find a suitable network of operating units which produces the desired products from the given raw materials. If we consider this process network design problem from a structural point of view, then we obtain a combinatorial optimization problem called the Process Network Synthesis or (PNS) problem. It is known that the PNS problem is NP-complete. Here, a new method is presented to reduce the solution of some more difficult PNS problems to the solution of simpler ones, and using this method, a new well-solvable class of PNS problems is established. Received February 12, 1999; revised October 24, 2000     

Use of Graduate Study in Psychology as a data source.

Comments on an article by C. M. Stoup and L. T. Benjamin, Jr. (see record 1983-24200-001), in which they used various editions of Graduate Study in Psychology, published by the American Psychological Association (APA), to report the GPAs and Graduate Record Examination scores of master's and doctoral students across various areas of psychology. It is cautioned that the use of Graduate Study in Psychology as a data source calls for skepticism, as there is sufficient reason to question some of the data that are submitted to the APA by psychology departments. (3 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Identification of Pd3+ ions in zeolite L by temperature programmed reduction and electron paramagnetic resonance spectroscopy

Pd supported on KL zeolite has been studied by temperature programmed reduction (TPR) and electron paramagnetic resonance (EPR) spectroscopy. It has been found that upon calcination in pure oxygen Pd³⁺ and Pd²⁺ ions are formed; the Pd³⁺ ions are identified by their EPR signal. As Pd³⁺ ions in the cancrinite cages are difficult to reduce, the H₂ consumption in conventional TPR is below the stoichiometric amount.