• Journal of Advanced Marine Engineering and Technology
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• v.21 no.2
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• pp.117-125
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• 1997

상계요소 해석(UBET) 프로그램은 비대칭 단조공정에서의 다이 충만과정과 단조 하중등을 예측하기 위하여 개발되었다. 보다 용이하게 단조 공정을 해석하기 위하여 비대칭 형상의 단조공정을 평면변형부(길이 부분)과 축대칭변형부(라운딩 부분)으로 나누었다. 평면변형부와 축대칭 변형부의 경계는 전단에너지를 고려하여 결합하는 빌딩 블록 방법(building block method)을 이용하였다. 그리고 본 연구의 비대칭 형상을 단조하는데 최적의 초기시편 형상으로 아령형의 시편(dumbbell-typed billet)을 제시하였다. 또한 실험은 상온에서 플라스티신을 사용하여 수행되었고 수치해석 결과와 실험결과는 비교적 잘 일치하였다.상계요소 해석(UBET) 프로그램은 비대칭 단조공정에서의 다이 충만과정과 단조 하중등을 예측하기 위하여 개발되었다. 보다 용이하게 단조 공정을 해석하기 위하여 비대칭 형상의 단조공정을 평면변형부(길이 부분)과 축대칭변형부(라운딩 부분)으로 나누었다. 평면변형부와 축대칭 변형부의 경계는 전단에너지를 고려하여 결합하는 빌딩 블록 방법(building block method)을 이용하였다. 그리고 본 연구의 비대칭 형상을 단조하는데 최적의 초기시편 형상으로 아령형의 시편(dumbbell-typed billet)을 제시하였다. 또한 실험은 상온에서 플라스티신을 사용하여 수행되었고 수치해석 결과와 실험결과는 비교적 잘 일치하였다.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.11 no.2
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• pp.3-12
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• 2001

Currently, the superscalar architecture dominates todays microprocessor marketplase. As, more transistors are integrated onto larger die, however, an on-chip multiprocessor is regarded as a promising alternative to the superscalar microprocessor. This paper examines the behavior of the next generation block encryption algorithms RC6 and Rijndael on the on-chip multiprocessing microprocessor. Based on the simulation results by using a program-driven simulator, the on-chip multiprocessor can exploit thread level parallelism effectively and overcome the limitation of instruction level parallelism in the next generation block encryption algorithms.

• Transactions of Materials Processing
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• v.3 no.2
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• pp.202-214
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• 1994

An upper bound elemental technique(UBET) is applied to predict the forging load and die-cavity filling for non-axisymmetric ring forging. In order to analyze the process easily, it is suggested that the finial product is divided into three different deformation regions. That is axisymmetric part in corner, lateral plane-strain part and shear deformation on boundaries between them. the place-strain and axisymmetric part are combinded by building block method. Also the total energy is computered through combination of three deformation part. Experiments have been carried out with pure plasticine billets at room temperature. The theoretical predictions of the forging load and the flow pattern are in good agreement with the experimental results.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.16 no.1
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• pp.123-136
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• 2018

The objective of this study is to propose a new methodology to fabricate a reliable engineering-scale buffer block, which shows homogeneous and uniform distribution in buffer block density, for in-situ experiments. In this study, for the first time in Korea, floating die press and CIP (Cold Isostatic Press) are applied for the manufacture of an engineering-scale bentonite buffer. The optimized condition and field applicability are also evaluated with respect to the method of manufacturing the buffer blocks. It is found that the standard deviation of the densities obtained decreases noticeably and that the average dry density increases slightly. In addition, buffer size is reduced by about 5% at the same time. Through the test production, it is indicated that the stress release phenomenon decreases after the application of the CIP method, which leads to a reduction in crack generation on the surface of the buffer blocks over time. Therefore, it is confirmed that the production of homogeneous buffer blocks on industrial scale is possible using the method suggested in this study, and that the produced blocks also meet the design conditions for dry density of buffer blocks in the AKRS (Advanced Korea Reference Disposal System of HLW).

• Journal of the Korean Geotechnical Society
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• v.38 no.12
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• pp.113-123
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• 2022

The required density relationship according to the press pressure of the floating die method and the homogeneity of the density distribution in the buffer block was evaluated to analyze the manufacturing characteristics of engineering scale bentonite-sand buffer blocks. In addition, the thermal conductivity was measured and compared with that of the pure bentonite buffer block to evaluate the level of thermal conductivity performance improvement of the bentonite-sand buffer material. As a result, it was confirmed that the standard deviation of dry density decreased to 0.011 and showed a homogeneous density distribution under the condition of press pressure greater than 400 kg/cm². Furthermore, as a result of the thermal conductivity test, the thermal conductivity of the buffer with optimum moisture content conditions was 1.345 and 1.261 W/(m·K) under the press pressure of 400 and 600 kg/cm², respectively. It increased by 16.1% and 11.0% compared to the pure bentonite buffer material. Based on the results of this study, it is judged that it can be used as fundamental data for manufacturing a homogeneous bentonite-sand buffer block on an engineering scale.

• The Journal of Korean Academy of Prosthodontics
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• v.34 no.4
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• pp.746-754
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• 1996

The purpose of this study was to evaluate the fracture strength of porcelain laminate veneer with various lingual extention length when incisal restoring. Sixty recently extracted, intact maxillary incisors were used and stored in a physiologic saline solution from the time of extraction. Seating form was preparation at the labial surface of each tooth with a water-cooled round diamond bur. Standard block was formed with 32 gauge and 24 gauge wax at tooth labial and lingual surface. Lingual extention length differed according to each group. (group I : 0.5mm, group II : 1 mm, group III : 2mm, group IV : 0mm) All tooth specimens were impressioned with examix(GC Inc., Japan). Refractory cast were maked with refractory die material(Ceramco Inc., U.S.A.) Laminate porcelain (Ceramco II Veneer porcelain, Ceramco Inc., U.S.A.) was condensed in refractory die cast and baked according to the manufacturer's recommendations. Each surface was contoured with low speed diamond bur according to guide block. All porcelain specimens were sandblasted and ultrasonically cleaned in distlled water for 3 minutes. Then, all porcelain specimen were etched with 8% hydrofluoric acid for 5 minutes. Sixty specimens were bonded with composite resin cement(Choice Porcelain Veneer System, Bisco Inc., U.S.A.) according to manufacture's directions. The fracture loads of the specimen were measured by Instron universal testing machine. The mean values of fracture loads for the groups were statistically compared by Duncan's multiful range test. The result were as follows : Mean fracture strengths of each group were 86.95Mpa in no lingual extention group, 44.98Mpa in 0.5mm lingual extention group, 27.47Mpa in 1mm lingual extention group, 19.61Mpa in 2mm lingual extention group. There was a statistically significant difference between all group(p<0.01).

• Journal of the Korean Institute of Telematics and Electronics B
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• v.29B no.2
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• pp.27-39
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• 1992

3 Dimensional measurement system using camera and laser slit-ray is studied. Precise calibration technique in this system is suggested. Calibration is accomplished with calibration die, calibration block and robot. For obtaining calibration parameters, the equations are solved using least square error method from a great many calibration points to reduce measuring error. Continuous measurement is possible for the object which is larger than one frame of camera. The efficiency and usability are proved by applying to the tire profile measuring system which measures tire profile using robot and this system.

• Journal of the KSME
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• v.33 no.4
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• pp.311-314
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• 1993

역설계란 제품에서부터 역으로 그것의 수학적인 형상을 얻는 기법이다. 생산현장과 설계분야에서 역설계의 응용사례는 많다. 예를 들면 자동차 외형설계자는 자유곡면(free form)을 만들고, 이것 에서 역으로 스템핑 다이(stamping die)를 가공한다. 물론 외형 설계자는 자유곡면을 생성하기 위해 스틸이나 커크사이트(kirtsite)보다는 원하는 형상을 만들기 쉬운 진흙을 사용한다. 생산부 서에서는 가공물의 설계도가 분실되거나 훼손되어 완성된 제품에서 도면이 복사되어야 할 경우가 생기게 된다. 역설계는 복제가 요구되는 어떤 형상도 적용이 가능하다. 응용대상은 특히 완구, 인조팔, 스템핑다이, 폼 블록(from block), 욕조기, 가구, 일상용품 등이며 적용대상은 광범위하다. 역설계는 설계자가 습득해야 할 필요기술이고, 현재의 CAD/CAM 적용영역을 새로운 세계로 확대시킬 것이다.

• Proceedings of the IEEK Conference
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• 1999.11a
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• pp.271-274
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• 1999

This paper proposes a simple architecture of digital dividing block in dual-modulus prescaler phase-locked loop used in the wireless communication. Proposed architecture eliminates a swallow counter in the conventional one and demonstrates the advantages in reducing the power consumption and the gate-counts. Therefore, it is suitable for small die area and low power applications. The circuit is designed in a standard 0.35${\mu}{\textrm}{m}$ CMOS process.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.11a
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• pp.385-386
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• 2008

In this paper, a simple dual band filter chip is designed with 0603 case size using IPD technology. The dual-band filter achieves high frequency band at 2.5 GHz and low frequency band at 1.8 GHz. The insertion losses in high frequency band and low frequency band are -0.195 dB and -0.146 dB, respectively. The return losses in these bands are -22.7 dB and -22.8 dB, respectively. The simple dual-band filter based on SI-GaAs substrate is designed within die size of about 1.3 $mm^2$.