Without considering the echo signal power changes caused by target distance changes during the accumulated time the traditional radar equation is hardly applied. We take account of the effects of velocity, signal-to-n...
详细信息
In this paper, nonlinear dynamic response under loss of coolant accident (LOCA) transient in the nuclear reactor coolant system (RCS) is investigated with ANSYS program. Many nonlinear factors, such as different struc...
详细信息
In this paper, nonlinear dynamic response under loss of coolant accident (LOCA) transient in the nuclear reactor coolant system (RCS) is investigated with ANSYS program. Many nonlinear factors, such as different structural stiffness in tension and compression, gap and plastic strain caused by main pipes' break etc. are considered. The Secondary development of ANSYS is performed to form the customized module for implementing effective parameterized and modular modeling and LOCA nonlinear analysis. Comparison of the results calculated by ANSYS and program-specific shows that the results are generally consistent, but there are some differences locally. According to the experience of transient dynamic analysis, and there are so many non-linear factors in the reactor coolant system, the difference is acceptable. The efficiency of this engineering analysis is improved remarkably with the convenience of input and modeling, viewable layout and automatic creating of reports, when using the customized module based on ANSYS.
This paper investigates the problem of designing fuzzy H∞ filter for a class of nonlinear singularly perturbed systems (SPSs) with time-varying delay in states. The considered system is approximated by a Takagi-Sugen...
详细信息
In wireless sensor networks (WSNs), trap coverage has recently been proposed to tradeoff between the availability of sensor nodes and sensing performance. It offers an efficient framework to tackle the challenge of li...
详细信息
In wireless sensor networks (WSNs), trap coverage has recently been proposed to tradeoff between the availability of sensor nodes and sensing performance. It offers an efficient framework to tackle the challenge of limited resources in large scale sensor networks. Currently, existing works only studied the theoretical foundation of how to decide the deployment density of sensors to ensure the desired degree of trap coverage. However, the practical issues such as how to efficiently schedule sensor node to guarantee trap coverage under an arbitrary deployment is still left untouched. In this paper, we formally formulate the Minimum Weight Trap Cover Problem and prove it is an NP-hard problem. To solve the problem, we introduce a bounded approximation algorithm, called Trap Cover Optimization (TCO) to schedule the activation of sensors while satisfying specified trap coverage requirement. The performance of Minimum Weight Trap Coverage we find is proved to be at most O(ρ) times of the optimal solution, where ρ is the density of sensor nodes in the region. To evaluate our design, we perform extensive simulations to demonstrate the effectiveness of our proposed algorithm and show that our algorithm achieves at least 14% better energy efficiency than the state-of-the-art solution.
COQ is an interactive theorem proving tool. The paper abstractly describes the feature of COQ, the architecture and working modes of PLC program with the example of typical PLC. It also introduces the first-order logi...
详细信息
COQ is an interactive theorem proving tool. The paper abstractly describes the feature of COQ, the architecture and working modes of PLC program with the example of typical PLC. It also introduces the first-order logic syntax and semantics of Intuitionistic Logic. It briefly introduces the main Gallina language syntax elements, the corresponding use methods and main theorem proving tactic on COQ. The work has modeled kernel data type and basic statements and and the denotational semantics of PLC program with Gallina. It has given the correctness proof of PLC program based on theorem proving, i.e. based on semantics function the relationship of configuration between the before codes execution and the after is proved. The main purpose is to prove whether a PLC program satisfies certain nature within a scan period.
The Micro- and Nano-mechanics Working Group of the Chinese Society of Theoretical and Applied Mechanics organized a forum to discuss the perspectives, trends, and directions in mechanics of heterogeneous materials in ...
详细信息
The Micro- and Nano-mechanics Working Group of the Chinese Society of Theoretical and Applied Mechanics organized a forum to discuss the perspectives, trends, and directions in mechanics of heterogeneous materials in January 2010. The international journal, Acta Mechanica Solida Sinica, is de- voted to all fields of solid mechanics and relevant disciplines in science, technology, and engineering, with a balanced coverage on analytical, experimental, numerical and applied investigations. On the occasion of the 30TM anniversary of Acta Mechanica Solida Sinica, its editor-in-chief, Professor Q.S. Zheng invited some of the forum participants to review the state-of-the-art of mechanics of heterogeneous solids, with a particular emphasis on the recent research development results of Chinese scientists. Their reviews are organized into five research areas as reported in different sections of this paper. ~I firstly brings in fo- cus on micro- and nano-mechanics, with regards to several selective topics, including multiscale coupled models and computational methods, nanocrystal superlattices, surface effects, micromechanical damage mechanics, and microstructural evolution of metals and shape memory alloys. ~II shows discussions on multifield coupled mechanical phenomena, e.g., multi-fields actuations of liquid crystal polymer networks, mechanical behavior of materials under radiations, and micromechanics of heterogeneous materials. In ~III, we mainly address the multiscale mechanics of biological nanocomposites, biological adhesive surface mechanics, wetting and dewetting phenomena on microstructured solid surfaces. The phononic crystals and manipulation of elastic waves were elaborated in ~IV. Finally, we conclude with a series of perspectives on solid mechanics. This review will set a primary goal of future science research and engineering application on solid mechanics with the effort of social and economic development.
A MISO cooperative transmission algorithm for clustering wireless sensor network is proposed in this paper. In this algorithm, we choose cooperative nodes according to cooperative threshold, and optimize nodes' tr...
详细信息
A MISO cooperative transmission algorithm for clustering wireless sensor network is proposed in this paper. In this algorithm, we choose cooperative nodes according to cooperative threshold, and optimize nodes' transmission power with finite-rate feedback. Then we analyze the implementation process in detail, derive the method of optimizing parameters. In the end verify this algorithm at simulation platform. The result shows that, this MISO cooperative transmission algorithm for clustering wireless sensor network can reduce transmission power of transmitting nodes effectively. So this algorithm can reduce the energy consumption, and also extend the life cycle of the whole wireless sensor network certainly.
Based on BPR theory, the new product development and manufacturing process status of a discrete manufacturing enterprise was analysed with finding out its existing problems, then a new reasonable process was designed ...
详细信息
Based on BPR theory, the new product development and manufacturing process status of a discrete manufacturing enterprise was analysed with finding out its existing problems, then a new reasonable process was designed and the model of management information system was established. Through the analysis of this case, this paper provides a reference for other similar enterprises to manage new product development and promote the development of enterprise information.
We have been developing a new tissue engineering technique for cartilage repair using a scaffold-free tissue engineered construct (TEC) bio-synthesized from synovium-derived mesenchymal stem cells (MSCs). A round-shap...
详细信息
The crystal structure of NaZr2(PO4)3, (NZP), contains three distinct crystallographic sites which between them can readily accommodate the majority of elements that are present in high level nuclear waste. The applica...
The crystal structure of NaZr2(PO4)3, (NZP), contains three distinct crystallographic sites which between them can readily accommodate the majority of elements that are present in high level nuclear waste. The applicability of this host phase to the immobilization of mixed zirconia/alumina waste from the Idaho Chemical Processing Plant (ICPP) was demonstrated. A waste form consisting of CaF2, a number of NZP phases and F-apatite was prepared and the results of leach testing reported. Detailed stability studies of the host sodium zirconium phosphate phase were also conducted as a function of temperature, pH and time.
暂无评论