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A position-sensitive pixel array silicon detector with a junction field effect transistor (JFET) switch structure is studied as a device for the direct illumination of X-ray from synchrotron light source. Considering an absorption length of silicon at an X-ray energy and a required thickness of a silicon, a 525 μ m n-type silicon wafer with high resistivity is chosen as the active volume of the detector and is depleted by applying a negative bias voltage to the junction side. The electron–hole pairs produced in an active volume by an X-ray illumination are collected on the electrodes . All pixels with one row are read in parallel and the next row is selected by the control voltage after one row has finished being read. The field shaper is introduced to produce inter-pixel isolation. We perform the simulation of the pixelated silicon position detector with JFET switch and present the characteristics of the transistor such as the drain current as a function of the voltage between the source and drain for different gate voltages. The fabrication processes of the pixel sensor with JFET switch structure based on the simulation result are also described.

Contour extracting plays an important role in image processing and computer vision, and it’s one of the most important components in low level processing. Based on many tests, this paper applies hue and texture as feature combined with mathematical morphology to have a rough segmentation of homogeneous objects, then restores the obtained contour based on h component. Tests prove that acceptable contour can be obtained. Compared with traditional method of contour extracting, the algorithm mentioned here includes self-differing, contour restoring based on hue and so on, so it has better robustness to light variation.

Probing the deep-depletion mode high-frequency capacitance-voltage (C-V) responses of MOS capacitors under photonic excitation, the distribution (D/sub it/) of the interface states (E/sub t/) at Si/SiO/sub 2/ heterojunctions was characterized. A photon energy E/sub ph/=0.943 eV (less than the silicon energy bandgap) was employed for the characterization of interface states in the photoresponsive energy band. In order to limit the photonic contribution to the change in the gate capacitance by excess carriers excited only from the interface states, a fast dc sweep rate (50 mV/s) with a high-frequency (500 kHz) small-signal was applied. Photonic C-V responses with a slow dc sweep for E/sub ph/=0.943 eV and a fast sweep for E/sub ph/=1.481 eV have been also provided for a comparison. Modulating the surface potential with the gate bias, a U-shaped distribution of D/sub it/ was obtained over the photoresponsive energy band in (E/sub C/-E/sub ph/)

Buckling and free vibration of stepped laminated composite beams were studied using simple higher-order theory (SHOT) which assumes a cubic distribution for the displacement field through the thickness. The results were compared to those from Euler-Bernoulli beam theory and Timoshenko's first-order shear beam theory. The results from SHOT did not show significant differences to those from Timoshenko theory for a wide range of aspect ratios of the beam geometry and material properties. In addition, the results from SHOT did not necessarily show more compliant results than those from Timoshenko beam theory. A two-dimensional (2-D) elasticity solution was obtained for the buckling of clamped-clamped beams to further investigate this phenomenon. The 1-D shear beam theories of Timoshenko and SHOT resulted in more compliant responses than 2-D solutions. The shear beam theories approached the 2-D solution from below while Euler-Bernoulli beam theory approached the 2-D solution from above.

This paper aims to develop and demonstrate intelligent diagnosis system that ensures effective supporting the decision-maker in determining the cause and potential solutions to unpredictable problems or events detected by monitoring factory-wide operating processes. The algorithm for accomplishing rapid, cost-effective, and high reliable diagnosis system is well-designed with C++ as an object-oriented programming language under Windows OS platform. A windows-based prototype system for intelligent diagnosis system with real-time status data collected from shop floor is also suggested and demonstrated by using C++ programming language and C4.5 learning algorithm.

New information technology and an upgrade process are needed for a nuclear plant to have the capability of performing the extended scope of a plant information system. The current modular component technology is to be used for a next generation plant to achieve the extended plant information system function. This paper describes the realization of the new information system function by the Web interface technique in the project for the development of a liquid metal reactor, KALIMER (Korea Advanced Liquid Metal Reactor). The current plant information system in the KALIMER project, which currently supports design process, consists of a design information system, analysis information system, user interface management system and plant information database. The design information system manages all design documents and data in the design process. The analysis information system analyzes calculation results made for plant safety and performance. The user interface management system manages the interface among hardware, software and users. Using these systems supported, remote users can have access to design data and process data conveniently by the Web and the systems reduce the time and cost required for the access, and also improve data accuracy.