闹龙河水库大坝安全监测系统综述

通过分析闹龙河水库大坝施工阶段情况,提出了坝体浸润线、坝基渗流压力及渗流量监测方案,并按照监测网点组建自动监测系统,利用各种软件功能,完成监测任务,为水库蓄泄调度运行提供依据。

Error Analysis of Three Degree-of-Freedom Changeable Parallel Measuring Mechanism

A three degree-of-freedom (DOF) planar changeable parallel mechanism is designed by means of control of different drive parameters. This mechanism possesses the characteristics of two kinds of parallel mechanism. Based on its topologic structure, a coordinate system for position analysis is set-up and the forward kinematic solutions are analyzed. It was found that the parallel mechanism is partially decoupled. The relationship between original errors and position-stance error of moving platform is built according to the complete differential-coefficient theory. Then we present a special example with theory values and errors to evaluate the error model, and numerical error solutions are gained. The investigations concentrating on mechanism errors and actuator errors show that the mechanism errors have more influences on the position-stance of the moving platform. It is demonstrated that improving manufacturing and assembly techniques can greatly reduce the moving platform error. The small change in position-stance error in different kinematic positions proves that the error-compensation of software can improve considerably the precision of parallel mechanism.

A new marine propulsion system

A new marine propulsion system is proposed . A small liquid sodium cooled reactor acts as prime mover; alkali-metal thermal-to-electric conversion ( AMTEC) cells are employed to convert the heat energy to electricity; superconducting magneto-hydrodynamic thruster combined with spray-water thruster works as pr opulsion. The configuration and characteristics of this system are described. Such a nuclear-powered propulsion system is not only free of noise, but also has high reliability and efficiency. It would be a preferable propulsion system for ships in the future.

Power loss reduction of distribution systems using BFO based optimal reconfiguration along with DG and shunt capacitor placement simultaneously in fuzzy framework

In distribution systems,network reconfiguration and capacitor placement are commonly used to diminish power losses and keep voltage profiles within acceptable limits.Moreover,the problem of DG allocation and sizing is great important.In this work,a combination of a fuzzy multi-objective approach and bacterial foraging optimization(BFO) as a meta-heuristic algorithm is used to solve the simultaneous reconfiguration and optimal sizing of DGs and shunt capacitors in a distribution system.Each objective is transferred into fuzzy domain using its membership function.Then,the overall fuzzy satisfaction function is formed and considered a fitness function inasmuch as the value of this function has to be maximized to gain the optimal solution.The numerical results show that the presented algorithm improves the performance much more than other meta-heuristic algorithms.Simulation results found that simultaneous reconfiguration with DG and shunt capacitors allocation(case 5) has 77.41%,42.15%,and 56.14%improvements in power loss reduction,load balancing,and voltage profile indices,respectively in 33-bus test system.This result found 87.27%,35.82%,and 54.34%improvements of mentioned indices respectively for 69-bus system.

Metamorphic Algorithm of Self-reconfigurable Modular Robotic System

A self-reconfigurable robot is a non-linear complex system composed of a large number of modules. The complexity caused by non-linearity makes it difficult to solve the problem of module motion planning and shape-changing control with the traditional algorithm. In this paper, a full-discrete metamorphic algorithm is proposed. The modules concurrently process the local sensing information, update their eigenvector, and act by the same predetermined logical rules. Then a reasonable motion sequence for modules and the global metamorphosis can be obtained. Therefore, the complexity of metamorphic algorithm is reduced, the metamorphic procedure is simplified, and the self-organizing metamorphosis can be obtained. The algorithm cases of several typical systems are studied and evaluated through simulation program of 2-D planar homogeneous modular systems.

Grayscale image encryption algorithm based on chaotic maps

A new image encryption/decryption algorithm has been designed using discrete chaotic systems as aSP (Substitution and Permutation) network architecture often used in cryptosystems. It is composed of two mainmodules: substitution module and permutation module. Both analyses and numerical results imply that the algo-rithm has the desirable security and efficiency.

A Contrastive Study on French and Urhobo Phonological Systems A Case Study of Articles and Demonstrative Structures

It is a general knowledge that French as a language is widely spoken internationally whereas Urhobo is mainly spoken in the geographical location where it belongs. It is also spoken, and this, sparingly so, by Urhobo persons in the Diaspora. Presently, Urhobo has become a language of study at the Delta State University, Abraka. It has also been included in the educational curriculum for study at the lower cadre of secondary school education in the Delta State. This situation has triggered the author＇s interest in doing a contrastive phonological study. The significance of this study is that it will highlight the salient differences in some of the grammatical aspects in the languages under consideration and also identify the difficulties that learners experience as a result of these difficulties. The author will also, as much as it is possible, proffer solutions to these learning difficulties.

Seismic Isolation of Reactor Assembly for a Fixed Base Accelerator Driven System Reactor Building

In the SILER （Seismic-Initiated events risk mitigation in LEad-cooled Reactors） Project, it is interesting to apply seismic isolation technology for the reactor assembly of the fixed base reactor building for ADS （Acceleration Driven System） heavy liquid reactor MYRRHA （Multipurpose Hybrid Research Reactor for High-Tech Application） which contains the most critical safety related components, such as reactor vessel, safe shutdown and control rod mechanisms, primary heat exchangers, primary pumps, spoliation target assembly and fuel assemblies, etc. The purpose of this paper is to investigate the possibility of an application of a partial seismic isolation to the safety critical components only, here, the reactor assembly. This paper presents the preliminary analysis results of the isolated reactor assembly and compares these with those of seismic isolated ADS reactor building. The analysis results show the reduction of the seismic acceleration response but the increase of the relative displacement for the reactor assembly. Some safety issues, especially, coolant＇s incapable covering the reactor core make difficult to apply for the partial seismic isolation of the ADS reactor assembly due to large relative displacement occurring the partial isolation system. Further study on the partial seismic isolation application of the critical safety components are also discussed.

Structural topology optimization: Extensibility and attainability

Extensibility and attainability of topology optimization are discussed by investigating a variety of simultaneous topology opti-mization methods extended from the standard formulation.First,the state of the art is highlighted through systematic classification of developed methods,such as simultaneous topology optimizations of microstructure and macrostructure,structure and supports,structure and design-dependent loads,structure and locations of involved components.Second,some recent results about simultaneous topology optimization of structure and applied loads are presented.It is shown that the simultaneous topology optimization is an integrated methodology that extends the concept of standard topology optimization in the sense of systematic design.The presence of more than one kind of design variable of different nature makes the optimization problem complex but enlarges the design space to attain the optimization.

A novel confidence estimation method for heterogeneous implicit feedback

Implicit feedback, which indirectly reflects opinion through user behaviors, has gained increasing attention in recommender system communities due to its accessibility and richness in real-world applications. A major way of exploiting implicit feedback is to treat the data as an indication of positive and negative preferences associated with vastly varying confidence levels. Such algorithms assume that the numerical value of implicit feedback, such as time of watching, indicates confidence, rather than degree of preference, and a larger value indicates a higher confidence, although this works only when just one type of implicit feedback is available. However, in real-world applications, there are usually various types of implicit feedback, which can be referred to as heterogeneous implicit feedback. Existing methods cannot efficiently infer confidence levels from heterogeneous implicit feedback. In this paper, we propose a novel confidence estimation approach to infer the confidence level of user preference based on heterogeneous implicit feedback. Then we apply the inferred confidence to both point-wise and pair-wise matrix factorization models, and propose a more generic strategy to select effective training samples for pair-wise methods. Experiments on real-world e-commerce datasets from Tmall.com show that our methods outperform the state-of-the-art approaches, consid- ering several commonly used ranking-oriented evaluation criteria.