家栖鼠对5种类型毒饵站的选择研究

目的 了解不同类型毒饵站对农村家栖鼠的控制效果。方法 用粘土烧制而成的一端开口和两端开口的弯管状毒饵站、花盆状毒饵站、两端开口的水泥盒和竹筒等 5种类型的毒饵站对农村家栖鼠进行选择实验。结果 害鼠在花盆状和竹筒毒饵站中的取食次数和取食量均较高 ,在平原区 ,取食次数分别占取食总次数的 2 3 .9%和 3 6.2 % ;取食量分别占总量的 2 6.4%和 3 9.0 % ;在丘陵区 ,分别占 5 0 .4%、2 4.8%和 5 0 .1%、2 4.0 %。结论 花盆状粘土类毒饵站和竹筒类毒饵站的制作工艺简单 ,取材方便 ,成本均较低 ,在农村大面积灭鼠及鼠类长期控制活动中可为首选。

凉血活血中药合门冬氨酸钾镁治疗淤胆型肝炎30例

1临床资料 本组病例均为我科1998年6月～2001年5月的住院病人.诊断符合1995年北京第5次全国传染病寄生虫病学术会议修订的病毒性肝炎诊断标准.

Analysis of Prese nt Operating Situati on of Large Size Coal-F ired Utility Boilers

Large size utility boilers develop rapidly in China, both their reliability and economics have reached better level. The operating situations of various existing boilers on the basis of different coals are analyzed, it is held that, the notable energy imbalance of furnace exit, ever existing in the tangential firing boilers has been solved, with comparatively lower NOX emission concentration of gained. The higher NOX emission concentration and furnace slagging etc. problems existing in wall firing boilers are notable. The comprehensive analysis shows that, it is appropriate to choose lower furnace volume heat release rate and higher flame height in the type selection design of boilers, and sufficient margin should be kept in the selection of coal pulverizing mills.

Mechanical characteristics of columnar jointed rock at dam base of Baihetan hydropower station

Irregular columnar jointed structure is a primary irregular columnar morphological tensile fracture. In order to study the geometric features of irregular columnar joints and the new problems in geotechnical engineering, hydraulic and hydropower engineering caused by columnar jointed basaltic mass, Voronoi graph from geometry was introduced to simulate the irregular columnar jointed basaltic mass at Baihetan hydraulic station. Discrete element software UDEC was used to simulate the whole process of rigid bearing plate test. Anisotropic constitutive of columnar joints was adopted to analyze the stress diffusion of rock mass at dam base of Baihetan. The results show that, the compaction property and hysteresis effect are well simulated based on discrete element simulation of Voronoi joint structure by UDEC. Four stages of cyclic loading and unloading process are imaged clearly. The results from in situ rigid bearing plate tests are explicated and the stress diffusion rule of anisotropic body is affected by structure surface. The elements in the stress state of 4-5 MPa are the most, about more than 35% of the total. Appropriate constitutive must be proposed to columnar jointed rock mass with different styles. It has important significance to realize the nonlinear mechanical behavior of irregular columnar jointed basaltic mass.

Implementation Study of Dynamic Load Balancing Algorithm of Parallel Tree Computation on Clusters of Heterogeneous Workstation

The rapid growth of interconnected high performance workstations has produced a new computing paradigm called clustered of workstations computing. In these systems load balance problem is a serious impediment to achieve good performance. The main concern of this paper is the implementation of dynamic load balancing algorithm, asynchronous Round Robin (ARR), for balancing workload of parallel tree computation depth-first-search algorithm on Cluster of Heterogeneous Workstations (COW) Many algorithms in artificial intelligence and other areas of computer science are based on depth first search in implicitty defined trees. For these algorithms a load-balancing scheme is required, which is able to evenly distribute parts of an irregularly shaped tree over the workstations with minimal interprocessor communication and without prior knowledge of the tree’s shape. For the (ARR) algorithm only minimal interprocessor communication is needed when necessary and it runs under the MPI (Message passing interface) that allows parallel execution on heterogeneous SUN cluster of workstation platform. The program code is written in C language and executed under UNIX operating system (Solaris version).

Best Effort Spectrum Allocation Scheme for Femtocell Networks in Dense Deployment

In orthogonal frequency division multiple access(OFDMA) based femtocell networks,the co-tier interference among femto base stations(FBS) becomes important in multiuser and densely deployed environment.In order to mitigate the co-tier interference and enhance the system total throughput,this paper proposed a best effort spectrum allocation scheme based on the extension of graph theory.In the scheme,a controller was proposed to collect the channel state information(CSI)of all femtocell user equipments(FUEs) in a certain range.Then,the controller evaluated the signal-to-interference Ratio(SIR) of each FUE and determined the set of its interference neighbors.By calculating the received power matrix(RPM) among FUEs and building interference graph matrix(IGM),different spectrum resource blocks(RBs) were assigned to the users with interference relation,while users without interference relation shared the same RBs,which could increase the spectrum efficiency.Simulation results show that the proposed algorithm can significantly improve the RB usage efficiency compared with the basic graph coloring theory,and more than 80% improvement can be acquired in dense deployment scenario.Besides,the throughput of both cell edge macro user equipments(MUEs) and cell edge FUEs is guaranteed on the premise of low interference.

Robust Analyzing Tools for Wind Turbine Blades Coupled with Multiobiective Optimization

This paper presents an approach that utilizes the recently developed tools for analyzing wind blade properties resulting from geometric shape and geographical site characteristics to find possible blade design improvements. A set of blade shapes with a certain deviation of chord distribution from the initial geometry was investigated for WindPACT 1.5 MW turbine. The results showed that the original blade geometry can be improved based on individual site wind characteristics, giving better aerodynamic efficiency and reduced cost.

Positioning performance analysis of the time sum of arrival algorithm with error features

The theoretical positioning accuracy of multilateration(MLAT) with the time difference of arrival(TDOA) algorithm is very high. However, there are some problems in practical applications. Here we analyze the location performance of the time sum of arrival(TSOA) algorithm from the root mean square error(RMSE) and geometric dilution of precision(GDOP) in additive white Gaussian noise(AWGN) environment. The TSOA localization model is constructed. Using it, the distribution of location ambiguity region is presented with 4-base stations. And then, the location performance analysis is started from the 4-base stations with calculating the RMSE and GDOP variation. Subsequently, when the location parameters are changed in number of base stations, base station layout and so on, the performance changing patterns of the TSOA location algorithm are shown. So, the TSOA location characteristics and performance are revealed. From the RMSE and GDOP state changing trend, the anti-noise performance and robustness of the TSOA localization algorithm are proved. The TSOA anti-noise performance will be used for reducing the blind-zone and the false location rate of MLAT systems.

The ＂Tiangong＂ Chinese Space Station project

1 Introduction The overall plan of the Chinese Space Station （CSS） project focuses on the grand goal of building a space station with Chinese characteristics, and adheres to the following basic principles： conforming to China＇s national conditions; building a station with modest scale and leaving room for extension; constructing a station with outstanding Chinese elements and core connotations; embodying the strategic goals of national development and driving innovation and development; pursuing technological advancement by employing modem advanced technologies to build and operate the CSS and mastering the construction and operation technology of large space facilities; focusing on the application efficiency for major innovation and technological achievements in the space application field; pursuing economical operations; and taking the road of sustainable development.

Adaptive robust beamformer for multi-pair two-way relay networks with imperfect channel state information

In wideband multi-pair two-way relay networks, the performance of beamforming at a relay station(RS) is intimately related to the accuracy of the channel state information(CSI) available. The accuracy of CSI is determined by Doppler spread, delay between beamforming and channel estimation, and density of pilot symbols,including transmit power of pilot symbols. The coefficient of the Gaussian-Markov CSI error model is modeled as a function of CSI delay, Doppler spread, and signal-to-noise ratio, and can be estimated in real time. In accordance with the real-time estimated coefficients of the error model, an adaptive robust maximum signal-to-interferenceand-noise ratio(Max-SINR) plus maximum signal-to-leakage-and-noise ratio(Max-SLNR) beamformer at an RS is proposed to track the variation of the CSI error. From simulation results and analysis, it is shown that: compared to existing non-adaptive beamformers, the proposed adaptive beamformer is more robust and performs much better in the sense of bit error rate(BER); with increase in the density of transmit pilot symbols, its BER and sum-rate performances tend to those of the beamformer of Max-SINR plus Max-SLNR with ideal CSI.