• International Journal of Fluid Machinery and Systems
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• v.2 no.3
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• pp.215-222
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• 2009

Jets issuing through small holes in a wall into a freestream has proven effective in the control of flow separation. This technique is known as the vortex generator jet (VGJs) method. If a precursor signal of separation is found, the separation control system using VGJs can be operated just before the onset of separation and the flow field with no separation is always attained. In this study, we measured the flow field and the wall static pressure in a two-dimensional diffuser to find a precursor signal of flow separation. The streamwise velocity measurements were carried out in the separated shear layer and spectral analysis was applied to the velocity fluctuations at some angles with respect to the diffuser. The pattern of peaks in the spectral analysis changes as the divergence angle increases over the angle of which the whole separation occurs. This change in the spectral pattern is related to the enhancement of the growth of shear layer vortices and appears just before the onset of separation. Therefore, the growth of shear layer vortices can be regarded as a precursor signal to flow separation.

• Journal of the Korean Institute of Telematics and Electronics C
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• v.34C no.9
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• pp.53-60
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• 1997

In this paper, an efficient BILBO(named EBILBO) is proposed for batch testing application when a BIST (built-in self test) circuit is implemented on ASIC. In a large and complex circuit, the proposed algorithm of batch testing has one pin-count that can easily control 4 test modes in the normal speed of circuit operation. For the implementation of the BIST cifcuit, the test patern needed is generated by PRTPG(pseudo-random test pattern generator) and the ouput is observed by proposed algorithm is easily modified, such as the modelling of test pattern genration, signature EBILBO area and performance of the implemented BIST are evaluated using ISCAS89 benchmark circuits. As a resutl, in a circuit above 600 gates, it is confirmed that test patterns are genrated flexibly about 500K as EBILBO area is 59%, and the range of fault coverage is from 88.3% to 100%. And the optimized operation frequency of EBILBO designed and the area are 50MHz and 150K respectively. On the BIST circit of the proposed batch testing, the test mode of EBILBO is able to execute as realtime that has te number of s$\^$+/n$\^$+/(2s/2p-1) clocks simultaneously with the normal mode of circuit operation. Also the proposed algorithm is made of the library with VHDL coding thus, it will be widely applied to DFT (design for testability) that satisfies the design and test field.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.8 no.7
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• pp.1576-1580
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• 2004

The recent trend of information communication is to focus on improving communication services in order to satisfy the customer's desire for various information. Optical transducers of Local Area Network use 850nm or 1310nm among wavelength ranges and LD as a light source. However, Vertical Cavity Surface Emitting Laser(VCSEL) which is very excellent to deal with data processing is used at long wavelength or Gbps. In this paper, after basic optical characteristics were introduced a optical transmission module was developed to be operated over GHz and its transmission characteristics were analyzed at 2.5GHz and 3GHz with pulse pattern generator.

• The Transactions of the Korea Information Processing Society
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• v.2 no.3
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• pp.425-432
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• 1995

In this paper we propose a design and implementation technique of a universal automatic test pattern generator(UATPG) which is well suited for VLSI digital circuits. UATPG is designed to extend the capabilities of the existing APTG and to provide a convenient environment to computer-aided design(CAD) users. We employ heuristic techniques in line justification and fault propagation for functional gates during test pattern generation for a target fault. In addition, the flip-flops associated with design for testability (DFT) are exploited for pseudo PIs and pseudo POs to enhance the testabilities of VLSI circuits. As a result, UATPG shows a good enhancement in convenient usage and performance.

• Journal of Radiation Industry
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• v.9 no.3
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• pp.131-135
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• 2015

The flow characteristics of fluid were measured using radioactive tracer in pilot scale digester with tray motion mixer. In consideration of the detection volume of the detector and the size of the digester, 20 detectors were installed in the digester. The radioactive tracer eluted 8 mCi of $^{68}Ga$ from $^{68}Ge/^{68}Ga$ generator was injected into the digester bottom. After radiotracer injection, the flow pattern was measured on the basis of the initial movement of the tracer until its diffusion completely. Most of tracer moved to the wall along the bottom of the digester, and then rose along the wall. The other tracer moved up along the mixer, and then moved to the wall direction along the surface.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2009.10a
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• pp.343-346
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• 2009

Since an LFSR as a pattern generator has solely linear dependency in itself, it generates sequences by moving the bit positions for a pattern generation. So the correlation between the generated patterns is high and thus reduces the possibility of fault detection. To overcome these problems many researchers have studied to have goodness of randomness between the output test patterns. In this paper, we propose the new and effective method to construct phase shifter as PRPG.

• Korean Journal of Materials Research
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• v.9 no.9
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• pp.919-925
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• 1999

Grain boundary characteristics and corrosion behavior of Alloy 600 material were investigated using the concept of grain boundary control by thermomechanical treatment(TMT). The grain boundary character distribution (GBCD) was analyzed by electron backscattered diffraction pattern. The effects of GBeD variation on intergranular at tack(JGA) and primary water stress corrosion cracking(PWSeC) were also evaluated. Changes in the fraction of coinci dence site lattice(CSL) boundaries in each cycle of TMT process were not distinguishable, but the total eSL boundary frequencies for TMT specimens increased about 10% compared with those of the commercial Alloy 600 material. It was found from IGA tests that the resistance to IGA was improved by TMT process. However, it was found from PWSCC test that repeating of TMT cycles resulted in the gradual decrease of the time to failure and the maximum load due to change in grain boundary characteristics, while the average crack propagation rate of primary crack increased mainly due to suppression of secondary crack propagation. It is considered that these corrosion characteristics in TMT specimens is attributed to 'fine tuning of grain boundary' mechanism.

• Journal of the Korean Institute of Intelligent Systems
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• v.13 no.3
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• pp.322-327
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• 2003

The water level of a steam generator of pressurized light water nuclear Power generator is known as a subject whose control is difficult because of a shrinking and swelling effect that is been mutually contradictory in a variation of feed water. In this paper, a neural network model selects first coordinative controller by a inappropriate gain of two PI controllers and the selected controller＇s gain is tuned by a fuzzy self-tuner. Model inputs consist of the water level, the feed water, and the stream flow. One controller of both coupling controllers whose gain is handled firstly is decided based upon above data. The proposed method can analyze patterns of signals using the characteristic of neural networks and select one controller that needs to be tuned through the observed result in this paper. If one controller between both the water level controller and the feed water controller is selected by the neural network model then a gain of the PI controller is suitably tuned by the fuzzy self-tuner. Rules of the fuzzy self-tuner drew from the pattern of input and output data. In the summary, the goal of this Paper is to select the suitable controller and tune the control gain of the selected controller suitably through such two processes.

• International Journal of Advanced Culture Technology
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• v.6 no.4
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• pp.275-283
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• 2018

Cancer show distinct pattern of gene expression when it is compared to normal. This difference results malignant characteristic of cancer. Many cancer drugs are targeting this difference so that it can selectively kill cancer cells. One of the recent demand for personalized treating cancer is retrieving normal tissue from a patient so that the gene expression difference between cancer and normal be assessed. However, in most clinical situation it is hard to retrieve normal tissue from a patient. This is because biopsy of normal tissues may cause damage to the organ function or a risk of infection or side effect what a patient to take. Thus, there is a challenge to estimate normal cell's gene expression where cancers are originated from without taking additional biopsy. In this paper, we propose in-silico based prediction of normal cell's gene expression from gene expression data of a tumor sample. We call this challenge as reverting the cancer into normal. We divided this challenge into two parts. The first part is making a generator that is able to fool a pretrained discriminator. Pretrained discriminator is from the training of public data (9,601 cancers, 7,240 normals) which shows 0.997 of accuracy to discriminate if a given gene expression pattern is cancer or normal. Deceiving this pretrained discriminator means our method is capable of generating very normal-like gene expression data. The second part of the challenge is to address whether generated normal is similar to true reverse form of the input cancer data. We used, cycle-consistent adversarial networks to approach our challenges, since this network is capable of translating one domain to the other while maintaining original domain's feature and at the same time adding the new domain's feature. We evaluated that, if we put cancer data into a cycle-consistent adversarial network, it could retain most of the information from the input (cancer) and at the same time change the data into normal. We also evaluated if this generated gene expression of normal tissue would be the biological reverse form of the gene expression of cancer used as an input.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2014.06a
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• pp.150-152
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• 2014

디지털 평판 LCD TV의 영상신호 전송에 LVDS가 사용되어 왔으나 케이블간의 타이밍 문제가 대두되고 초고해상도의 컬러 Depth 확장으로 인해 보다 빠른 전송속도가 요구되어진다. V-by-One HS는 초고해상도 영상처리 IC 및 TCON 간의 새로운 인터페이스 기술로서 최대 3840*2160@240Hz의 해상도 영상구현이 가능하다. 동작 주파수 대역의 공진모드 전압 분포와 V-by-One HS IBIS(Input/Output Buffer Information Specification) 모델 시뮬레이션을 통하여 PCB 설계 방법을 제안한다. 본 논문에서는 V-by-One HS 인터페이스 기술을 사용하여 초고해상도 영상패턴 제어 신호발생기의 시스템 구성을 제안하고 고속영상 신호에 대한 신호 무결성을 검증하고자 한다.