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16th International Topical Meeting on nuclear Reactor Thermal Hydraulics, NURETH 2015

作者： Chahi, H. Kästner, W. Alt, S. Department of Nuclear Engineering/Soft Computing Institute of Process Technology Process automation and measuring technology University of Applied Sciences Zittau/Gorlitz Zittau Germany

ISBN: (纸本)9781510811843

This research project supported by the German Federal Ministry of Education and Research named SINABEL (Safety of spent fuel pools: Experimental analysis, modeling and validation of system and CFD codes) delivers with a combination of experiments and simulations, knowledge's of the heat transfer processes for the case of a partially or completely evaporated spent fuel storage pool in light water reactor nuclear power plants both within the fuel rod bundle of a fuel assembly (FA) and in the spaces between the FA in order to be able to predict via the modeling and simulation the development of the axial and radial temperature profiles of rods by different accident scenarios. SINABEL is a joint research project which three research institutions (TU-Dresden, HZDR and HSZG) work together. One of the main focus in this project is the investigation of the flow behavior by separate effect experiments in a single 16x16 PWR-FA-dummy (pressurized water reactor fuel assembly) to study the vertical density-driven exchange movements of gases within and above the FA-bundle. By means of these small scale experiments the flow behavior will be investigated using optical observations facilities for air, replacement atmospheres for superheated steam (e.g. through model fluids). The operational capability is also to be tested as part of this work. The measuring results in this project include the dynamic behavior of gas concentrations and local velocity vectors, turbulent structures of oppositely directed gas flows. In this paper the experimental design and results of preliminary isothermal experiments at a shortened PWR-FA-dummy are presented which are based on acquired knowledge's from experiments at a heated BWR-FA-dummy-rig and descriptions of fluid dynamic process in FA. The paper illustrates for example the Re-number dependent pressure drop in FA-dummy and the velocity distribution, as well as determines which model gas is well suited to model the overheated steam by application o

关键词： Lakes

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Performance assessment of Cs I(T1) screens on various substrates for X-ray imaging

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Chinese Physics C 2015年第7期39卷 102-106页

作者：冯召东蒋鹏张红凯赵博震秦秀波魏存峰刘宇魏龙 Key Laboratory of Nuclear Radiation and Nuclear Energy Technology Institute of High Energy PhysicsChinese Academy of Sciences Beijing Engineering Research Center of Radiographic Techniques and Equipment University of Chinese Academy of Sciences The College of Nuclear Technology and Automation Engineering Chengdu University of Technology

Thallium-doped cesium iodide（Cs I（Tl）） screens are widely used in X-ray imaging devices because of the columnar structure of the Cs I（Tl） layer, but few reports focus on the optical role of the substrate in the screen *** this paper, four substrates including fused silica（Si O2）, silver-film coated Si O2, graphite（C） and fiber optic plate（FOP） are used to fabricate Cs I（Tl） screens by thermal evaporation. Their imaging performance is evaluated by relative light output（RLO）, modulation transfer function（MTF）, normalized noise power spectrum（NNPS） and noise equivalent quanta（NEQ）. The results reveal that although Cs I（Tl） film on graphite plate yields images with the lowest light output, it presents relatively higher spatial resolution and better signal-to-noise ***, films on Si O2 plate obtain low MTF but high NNPS curves, whether they are coated with silver film or ***, scintillation screens on FOP have bright images with low NNPS and high NEQ, but have the lowest MTF. By controlling the substrate optical features, Cs I（Tl） films can be tailored to suit a given application.

关键词： Cs I（T1） scintillation screen substrate imaging performance evaluation

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Setup for laboratory studies of the environmental conditions influence on the fixed charge state in silicon dioxide

Setup for laboratory studies of the environmental conditions...

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作者： Kushpil, S. Kushpil, V. Mikhaylov, Vasily Nuclear Physics Institute Academy of Sciences of the Czech Republic Øež Czech Republic Czech Technical University in Prague Faculty of Nuclear Sciences and Physical Engineering Prague Czech Republic National Research Tomsk Polytechnic University Institute of Physics and Technology Department of Electronics and Automation of Nuclear Plants Tomsk Russia

The position sensitive detectors operate in high intensity radiation field of the collider experiment [1]. Important task is to estimate the influence of different radiation effects on properties of the detector. We focus on the laboratory studies to estimate the reliability of different types of silicon detectors. We use the simple test structures produced by standard technology for the silicon detectors. We give the primary attention to the case when the depth of active detector region varies from 10 to 20 µm because it leads to the most significant influence of SiO2-Si interface on processes in silicon bulk. We present the experimental results of long term irradiation test with Am241 (one year). Influence of the environmental conditions on the fixed charge states in silicon dioxide was investigated using developed simple model. © 2015 IOP Publishing Ltd and Sissa Medialab srl.

关键词： Silica

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High-performance femtosecond laser fabrication of plasmon elements using DOE

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AIP Conference Proceedings 2017年第1期1874卷

作者： P. A. Danilov E. P. Litovko S. I. Kudryashov A. A. Kuchmizhak A. Porfirev O. B. Vitrik S. Ph. Umanskaya 1Lebedev Physical Institute 119991 Moscow Russia 2Moscow Institute of Physics and Technology (National University) 141701 Dolgoprudny Moscow region Russia 3ITMO University St. Peterburg 197101 Russia 5National Research Nuclear University MEPhI (Moscow Engineering Physics Institute) 115409 Moscow Russia 4Institute of Automation and Control Processes Far Eastern Branch Russian Academy of Science Vladivostok 690041 Russia 6Samara National Research University Moskovskoe shosse 34 Samara 443086 Russia

Broadband optically tunable diffractive optical elements (DOEs) were used to generate structured optical beams with considerably increased focal depth. Such beams were justified for high-performance ablative and translative printing of various plasmonic elements via high-efficiency multiplexing of femtosecond Gaussian-shaped laser beams to multiple micro-beams. The increased focal depth of such DOEs and easy-to-implement optical structuring of output beams as well as their high multiplexing efficiency make them very useful devices for high-performance laser fabrication of surface-enhanced infrared absorption sensors.

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Investigation of the release of zinc in the reactor sump and the behavior of dissolved zinc at hotspots in the reactor core after a loss of coolant accident 16

Investigation of the release of zinc in the reactor sump and...

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16th International Topical Meeting on nuclear Reactor Thermal Hydraulics, NURETH 2015

作者： Rcngcr, S. Alt, S. Kästner, W. Seeliger, A. Kryk, H. Department of Nuclear Engineering / Soft Computing Institute of Proccss Technology Proccss Automation and Measuring Technology University Ol'Applied Sciences Zittau/Gdrlitz Theodor-Kömer-Allee 16 Zittau02763 Germany Institute of Fluid Dynamics Helmholtz-Zentrum Dresden-Rosscndorf P.O. Box 510119 Dresden01314 Germany

ISBN: (纸本)9781510811843

Generic experimental and methodical investigations were carried out aiming at the systematic elucidation of physico-chemical mechanisms and their influence on thermo-hydraulic processes, which can occur during the sump circulation operation after a loss-of-coolant accident (LOCA) in PWR. In such a case, borated coolant with dissolved zinc, formed by corrosion of zinc-coated containment installations, may teach core regions of higher temperature (hot spots). Experimental studies were done at semi-technical scale focused on the influence of such zinc-containing coolants on thermo-hydraulics at heating configurations similar to those inside the PWR core. The impact of physico-chemical mechanisms on thermo-fluid-dynamical behavior of coolant inside a 3-3 configuration of heating rods, which net as fuel rod simulators with spacer segments, was determined. As a test parameter, borated coolant with dissolved zinc was used with an initial fluid temperature in the range of 45...50°C. The initial boric acid concentration in the experiments is based on the accident scenario in German PWR. In the ease of a ***. emergency cooling water (containing 2,500 ppm boron) from two refueling water storage tanks is injected into the primary cooling circuit during LOCA. During heat-up of zinc-containing coolant in a circuit, an increasing turbidity of the coolant fluid caused by forming colloids was observed first. This was followed by the formation of solid corrosion products consisting of zinc borates (identified by means of Raman spectroscopy [2]) In dependence of the temperatures of fluid and heatable surfaces, the solids showed various attributes concerning their mobilization potential, their density and their ability to form deposit layers Deposits occurred at the rod surfaces as well as at the spacer segments. They effected a hindered heat transfer from the rod surfaces to the fluid, an increasing head loss at the spacers and some changes of the flow distribution. In addition, qua

关键词： Deposits

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Study of recursive model for pole-zero cancellation circuit

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nuclear Science and Techniques 2014年第1期25卷 38-42页

作者：周建斌洪旭王仁波周伟胡云川万新峰杜鑫 College of Nuclear Technology and Automation Engineering Chengdu University of Technology Engineering Research Center of Nuclear Technology Application Ministry of EducationEast China institute of Technology Engineering Research Center of Nuclear Technology Application Ministry of EducationEast China institute of Technologya

The output of charge sensitive amplifier(CSA) is a negative exponential signal with long decay time which will result in undershoot after C-R ***-zero cancellation(PZC) circuit is often applied to eliminate undershoot in many radiation ***,it is difficult to use a zero created by PZC circuit to cancel a pole in CSA output signal accurately because of the influences of electronic components inherent error and environmental factors.A novel recursive model for PZC circuit is presented based on Kirchhoff's Current Law(KCL) in this *** model is established by numerical differentiation algorithm between the input and the output *** simulation experiments for a negative exponential signal are carried out using Visual Basic for Application(VBA) program and a real x-ray signal is also *** results show that the recursive model can reduce the time constant of input signal and eliminate undershoot.

关键词：零极点对消递归模型消除电路基尔霍夫电流定律数值微分算法电荷灵敏放大器指数信号输出信号

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Molecular Dynamics Simulation of Xe Behavior in U-Mo Alloys Fuel

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Chinese Physics Letters 2014年第4期31卷 130-133页

作者： XIAO Hong-Xing TANG Rui TIAN Xiao-Feng LONG Chong-Sheng Science and Technology on Reactor Fuel and Materials Laboratory Nuclear Power Institute of China Chengdu 610041 The College of Nuclear Technology and Automation Engineering Chengdu University of Technology Chengdu 610059

Classical molecular dynamics simulations are used to investigate the fission gas Xe behavior in a U-Mo alloy fuel matrix. The embedded atom method potential proposed by Smirnova et al. is used to describe the U-Mo-Xe system. The results show that the initial configuration of interstitial Xe atoms in U-Mo alloys is very instable and has a strong tendency to get together and to form a Xe bubble by ejecting the adjacent U atoms and Mo atoms from their former normal lattice sites. The pressure in Xe bubbles is initially quite high and then drops with increasing Xe concentration obviously. The matrix swelling of U-Mo alloys associated with the Xe bubble growth follows approximately a linear relationship with the ratio of Xe to U at low Xe concentration while the rate of swelling increases rapidly at high Xe concentration. The simulation results are in good agreement with the experimental data. The recovery of the damaged structure in the U-Mo alloys matrix is also investigated. It is shown that a damaged structure cannot be recovered completely after a system is relaxed for a long time while still having lots of defects.

关键词： MOLECULAR dynamics -- Simulation methods XENON THERMAL properties FISSION gases SWELLING of materials NUCLEATION

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A Robust Vehicle License Plate Character Extraction Method

A Robust Vehicle License Plate Character Extraction Method

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2015 International Conference on Applied Mechanics and Mechatronics engineering(AMME 2015)

作者： Ji-shi GUAN Yao-wu SHI Jian-wen QIU Yi-min HOU School of Communication Engineering Jilin University China Nuclear Power Technology Research Institute Beijing Division School of Automation Engineering Northeast Dianli University

The Paper proposes a robust license character extraction method aimed to some problem in this topic. The maximum entropy method is used to segment the license images. The combination of parallel and serial scan is employed to thin the images to extract the skeleton. The Hough Transform is used to extract the line of the license edge and get the incline degree and rectify the images. Used the horizontal scan method to confirm the area of character. Used the horizontal projection to get areas of every character so that to recognize them. The experiment results show that the segment method is adaptive for images in different brightness, the horizontal scan can get the whole character area fast and the method is a robust one.

关键词： Maximum entropy Horizontal scan Hough transform Character extraction

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Unsupervised Image Segmentation Based on Expectation-Maximization Algorithm

Unsupervised Image Segmentation Based on Expectation-Maximiz...

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2015 International Conference on Applied Mechanics and Mechatronics engineering(AMME 2015)

The paper proposes a novel image segmentation method based on ExpectationMaximization and Bayesian Information Criterion. The Expectation-Maximization theory is used to estimate the data distribution of the input image firstly. The number of class is calculated by Bayesian Information Criterion. The Maximum Likelihood is employed to classify the image pixels into the nearest class. The excellence of the proposed method is being independent to original estimate and it can be used in unsupervised image segmentation. The real images are used in the experiment. The results show that this method is efficient.

关键词： Expectation-maximization Bayesian information criterion Image segmentation

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Robotic bodily aware interaction within human environments

Robotic bodily aware interaction within human environments

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SAI Intelligent Systems Conference (IntelliSys)

作者： Bojan Jerbic Tomislav Stipancic Tomislav Tomasic Dept. of Robotics and Production System Automation Faculty of Mechanical Engineering and Naval Architecture Zagreb Croatia Institute for Nuclear Technology Zagreb Croatia

This paper describes an approach in which a robot is using a virtual or inner representation of its own body to ensure a safe and efficient interaction within the physical world. By analysing correlations within its surroundings, the robot is able to plan task-oriented and socially accepting responses. This approach is inspired by the phenomenon called bodily awareness, which is found in humans. Compared to conventional approaches where robots are preprogramed to react on finite number of environmental occurrences or states, the proposed approach gives the robot an ability to adapt to changes through a constant interaction. To achieve this, a robot interaction space is discretized and constantly analysed. As a part of the new cognitive model, a virtualized image of the robot body is used to avoid all possible collisions. The model also contains a probabilistic component to provide the most appropriate solution to given environmental conditions where the environment is naturally highly dynamic and unpredictable.

关键词： Robot kinematics Collision avoidance Robot sensing systems Service robots Computational modeling Three-dimensional displays

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