A moored underwater energy conservation system for profiling measurement

There is a need to obtain the hydrologic data including ocean current, wave, temperature and so on in the South China Sea. A new profiling instrument which does not suffer from the damage due to nature forces or incidents caused by passing ships, is under development to acquire data from this area. This device is based on a taut single point mid-water mooring system. It incorporates a small, instrumented vertically profiling float attached via an electromechanical cable to a winch integral with the main subsurface flotation. On a pre-set schedule, the instrument float with sensors is winched up to the surface if there is no strip passing by, which is defined by an on-board miniature sonar. And it can be immediately winched down to a certain depth if the sonar sensor finds something is coming. Since, because Of logistics, the area can only be visited once for a long time and a minimum of 10 times per day profiles are desired, energy demands are severe. To respond to these concerns, the system has been designed to conserve a substantial portion of the potential energy lost during the ascent phase of each profile and subsequently use this energy to pull the instrument down. Compared with the previous single-point layered measuring mode, it is advanced and economical. At last the paper introduces the test in the South China Sea.

协同过滤推荐系统的标签网络整合及增量化

随着信息过载问题越来越突出，如何有获地提取互联网上的信息成为近年来的一个研究热点。个性化推荐系统（Personalized Recommender System）利用用户的兴趣为其推荐最相关的互联网信息，已成功部署于搜索引擎、电子商务、网上社区等互联网关键应用中，是信息检索界的一个突破性的领域。个性化推荐系统的广泛商业应用对其性能提出了严格的要求，而数据的稀疏性和海量性 大大限制了推荐的质量。为了获得更高的准确性和可扩展性，协同过滤方法的 成功应用提供了一条解决之路。协同过滤的思想是利用兴趣相投、经验相似的 群体的喜好来为其内部成员推荐感兴趣的信息，用户通过如评分等的机制表现 自己的偏好以达到为自己和他人过滤信息的目的。作为目前最成功的推荐方法， 协同过滤的应用已经比较成熟。然而这种推荐系统仍有很大改进余地。 标签网络（Folksonomy）是一种最近兴起的社会网络资源，用户通过对浏览 过的物品进行注释或给予标签达到对其归类的作用。像这样对同一物品集合的给予标签的行为就形成这被称为标签网络的社会网络。协同过滤的思想无疑可以用于这些数据，为这些用户对这一物品集合内的元素给予推荐。将标签网络数据融入原基于评分的推荐系统，是我们的主要贡献之一。我们提出了两种具体地使用标签网络数据辅助评分预测的方法。一种是友邻方法，直接利用聚类方法寻找相似的用户或物品；另一种是联合矩阵分解，利用机器学习领域的矩阵分解拟合未知元素的方法预测评分。这两种方法的想法的初衷均来源于协同过滤技术面对的数据的一个棘手的特性，数据稀疏性。伴随着协同过滤的发展还有另外一个问题，那就是数量的巨大维度。对这一问题，我们提出了一种增量化方法使推荐系统适应目益增长的数据量。协同过滤方法中有一大类是利用聚类算法做出推荐，我们所提出的改进细化了聚类算法的粒度，使每次聚类都是有针对性地对小容量的集合进行操作。我们将改进的矩阵分解方法应用于每个集合的聚类操作上，使得相似的用户和物品之间的关系更加紧密。这在数据更新率很高的情况下可以避免不断重新将整个数据集进行训练的问题。我们通过实验对比了流行的若干种推荐算法，证明了我们所提出的方法均有着比较大的性能提升。不仅仅拥有更高的准确性，而且也拥有非常好的可扩展性（即算法时间复杂度与数据规模线性相关）。

Parallel Fully-Implicit Computation of MHD Acceleration Experiments

A three-dimensional MHD solver is described in the paper. The solver simulates reacting flows with nonequilibrium between translational-rotational, vibrational and electron translational modes. The conservation equations are discretized with implicit time marching and the second-order modified Steger-Warming scheme, and the resulted linear system is solved iteratively with Newton-Krylov-Schwarz method that is implemented by PETSc package. The results of convergence tests are plotted, which show good scalability and convergence around twice faster when compared with the DPLR method. Then five test runs are conducted simulating the experiments done at the NASA Ames MHD channel, and the calculated pressures, temperatures, electrical conductivity, back EMF, load factors and flow accelerations are shown to agree with the experimental data. Our computation shows that the electrical conductivity distribution is not uniform in the powered section of the MHD channel, and that it is important to include Joule heating in order to calculate the correct conductivity and the MHD acceleration.

Liquid nitrogen flowrate alarm system for MBE

Liquid nitrogen is very important for MBE system. Most MBE systems use the liquid nitrogen to absorb the impurity molecules. If MBE cryoshroud is lack of liquid nitrogen, the pressure of the growth chamber will grow. This will affect the film quality. But too much liquid nitrogen is a waste. We have developed a liquid nitrogen flowrate alarm system to monitor the liquid nitrogen status in MBE cryoshroud. In this method, a temperature sensor is placed at the end of the cryoshroud. The temperature varies with changing of the liquid nitrogen status in cryoshroud. If the liquid nitrogen level in the cryoshroud is too low or too high, the LNFA will send out an alarm to warn the user to adjust the liquid nitrogen flowrate. In our experiments, we found this method works well, and the temperature responds sensitively. With the help of this system, people can view the liquid nitrogen status of the entire growth process. Compare with other method. it is very cheap.

scenario-based interactive intention understanding in pen-based user interfaces

Interactive intention understanding is important for Pen-based User Interface (PUI). Many works on this topic are reported, and focus on handwriting or sketching recognition algorithms at the lexical layer. But these algorithms cannot totally solve the problem of intention understanding and can not provide the pen-based software with high usability. Hence, a scenario-based interactive intention understanding framework is presented in this paper, and is used to simulate human cognitive mechanisms and cognitive habits. By providing the understanding environment supporting the framework, we can apply the framework to the practical PUI system. The evaluation of the Scientific Training Management System for the Chinese National Diving Team shows that the framework is effective in improving the usability and enhancing the intention understanding capacity of this system.

Parallel Fully-Implicit Computation of Magnetohydrodynamics Acceleration Experiments

A three-dimensional MHD solver is described in the paper. The solver simulates reacting flows with nonequilibrium between translational-rotational, vibrational and electron translational modes. The conservation equations are discretized with implicit time marching and the second-order modified Steger-Warming scheme, and the resulted linear system is solved iteratively with Newton-Krylov-Schwarz method that is implemented by PETS,: package. The results of convergence tests arc plotted, which show good scalability and convergence around twice faster when compared with the DPLR method. Then five test runs are conducted simulating the experiments done at the NASA Ames MHD channel, and the calculated pressures, temperatures, electrical conductivity, back EMF, load factors and flow accelerations are shown to agree with the experimental data. Our computation shows that the electrical conductivity distribution is not uniform in the powered section of the MHD channel, and that it is important to include Joule heating in order to calculate the correct conductivity and the MHD acceleration.

Development of multi-channel gated integrator and PXI-DAQ system for nuclear detector arrays

A multi-channel gated integrator and PXI based data acquisition system have been developed for nuclear detector arrays with hundreds of detector units. The multi-channel gated integrator can be controlled by a programmable Cl controller. The PXI-DAQ system consists of NI PXI-1033 chassis with several PXI-DAQ cards. The system software has a user-friendly GUI which is written in C language using LabWindows/CVI under Windows XP operating system. The performance of the PXI-DAQ system is very reliable and capable of handling event rate up to 40 kHz. (C) 2010 Elsevier B.V. All rights reserved.

Information system for ICP-AES in Windows environment

An information system for inductively coupled plasma atomic emission spectrometry (TCP-BES) in MS Windows environment was developed based on the previous work in the laboratory. The system contains the data of about 28 000 spectral lines and a function of ICP spectral simulation,so it would be very helpful for line selection. The system also contains the Kalman filter and factor analysis programmes written with MS Visual Basic(version 4.0), which can be used for spectral interference correction and peak position optimization. A large amount of real spectral scanning data of rare earth elements were included in the system for user's references. All these characteristics made the system more useful and practical.

Tectonic geomorphology of the Ryukyu Trench-Arc-Backarc System: geological-geophysical exploration and mapping

OKINAWA TROUGH; BASIN

地震勘探三维可视化方法研究与实现

This thesis mainly studies the technologies of 3-D seismic visualization and Graphic User Interface of seismic processing software. By studying Computer Graphics and 3-D geological modeling, the author designs and implements the visualization module of seismic data processing software using OpenGL and Motif. Setting seismic visualization flow as the subject, NURBS surface approximation and Delaunay Triangulation as the two different methods, the thesis discusses the key algorithms and technologies of seismic visualization and attempts to apply Octree Space Partitioning and Mip Mapping to enhance system performance. According to the research mentioned above, in view of portability and scalability, the author adopts Object-oriented Analysis and Object-oriented Design, uses standard C++ as programming language, OpenGL as 3-D graphics library and Motif as GUI developing tool to implement the seismic visualization framework on SGI Irix platform. This thesis also studies the solution of fluid equations in porous media. 2-D alternating direction implicit procedure has been turned into 3-D successive over relaxation iteration, which possesses such virtues as faster computing speed, faster convergence rate, better adaptability to heterogeneous media and less memory demanding.