20 research outputs found

    Integrated cosmic muon flux in the zenith angle range 0<cosθ<0.370 < \text{cos}\theta < 0.37 for momentum threshold up to 11.6 GeV/c

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    We have measured the cosmic muon flux in the zenith angle range<cosθ<0.37 with a detector comprising planes of scintillator hodoscope bars and iron blocks inserted between them. The muon ranges for up to 9.5 m-thick iron blocks allow the provision of muon flux data integrated over corresponding threshold momenta up to 11.6 GeV/c. Such a dataset covering the horizontal direction is extremely useful for a technique called muon radiography, where the mass distribution inside a large object is investigated from the cosmic muon distribution measured behind the object

    Detection of on-surface objects with an underground radiography detector system using cosmic-ray muons

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    We have developed a compact muon radiography detector to investigate the status of the nuclear debris in the Fukushima Daiichi Reactors. Our previous observation showed that a large portion of the Unit-1 Reactor fuel had fallen to floor level. The detector must be located underground to further investigate the status of the fallen debris. To investigate the performance of muon radiography in such a situation, we observed 2 m cubic iron blocks located on the surface of the ground through different lengths of ground soil. The iron blocks were imaged and their corresponding iron density was derived successfully

    Imaging the inner structure of a nuclear reactor by cosmic muon radiography

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    We studied the inner structure of the nuclear reactor of the Japan Atomic Power Company (JAPC) at Tokai, Japan, by muon radiography. Muon detectors were placed outside the reactor building. By detecting cosmic muons penetrating the wall of the reactor building, we could successfully identify objects such as the containment vessel, pressure vessel, and other structures of the reactor. We also observed a concentration of heavy material which can be attributed to the nuclear fuel assemblies stored in the nuclear fuel storage pool

    Research and Design of a Routing Protocol in Large-Scale Wireless Sensor Networks

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    无线传感器网络,作为全球未来十大技术之一,集成了传感器技术、嵌入式计算技术、分布式信息处理和自组织网技术,可实时感知、采集、处理、传输网络分布区域内的各种信息数据,在军事国防、生物医疗、环境监测、抢险救灾、防恐反恐、危险区域远程控制等领域具有十分广阔的应用前景。 本文研究分析了无线传感器网络的已有路由协议,并针对大规模的无线传感器网络设计了一种树状路由协议,它根据节点地址信息来形成路由,从而简化了复杂繁冗的路由表查找和维护,节省了不必要的开销,提高了路由效率,实现了快速有效的数据传输。 为支持此路由协议本文提出了一种自适应动态地址分配算——ADAR(AdaptiveDynamicAddre...As one of the ten high technologies in the future, wireless sensor network, which is the integration of micro-sensors, embedded computing, modern network and Ad Hoc technologies, can apperceive, collect, process and transmit various information data within the region. It can be used in military defense, biomedical, environmental monitoring, disaster relief, counter-terrorism, remote control of haz...学位:工学硕士院系专业:信息科学与技术学院通信工程系_通信与信息系统学号:2332007115216

    Prototype performance of Distributed DAQ using HORB based on Java

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    Network programming is a very important technology for next generation of distributed DAQ system. Java has powerful functionality not only in GUI but also in network programming. Execution speed of Java program is slow on Java interpreter. We have investigated various benchmark programs on Java interpreter, Java Just In Time compiler and Java compiler which generates native codes, and evaluated the performance of them in comparison with that of the C native codes. We found that the performance of the Java compiler was nearly as good as that of the C native codes. Hence, a prototype of Java-based DAQ has been developed. Our goal is to establish 3 tier (DAQ client, DAQ server and DAQ database) model for the DAQ
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