• 한국컴퓨터정보학회논문지
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• 제23권7호
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• pp.1-10
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• 2018

In this paper, we propose the principles and design details of Automatic cable assembly test system and show its utility. Testing the cable assembly is required periodically or non-periodically in the system that the cable assembly performance is quite important like military equipment. There are several weaknesses when humans test the cable assembly manually. It not only takes much time but also could happen human error. To improve these disadvantages, I developed Automatic cable assembly test system. The system can be implemented by building switching control system that connect and disconnect the cable assembly and measuring devices. Through the result of the cable assembly test with this test system, we show this system makes test time short and improves of test reliability as compared with manual test.

• 한국압력기기공학회 논문집
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• 제12권1호
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• pp.11-16
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• 2016

Fuel assembly's mechanical characterization test facility (FAMeCT) in KAERI was constructed with upgraded functional features such as increased loading capacity, underwater vibration testing and severe earthquake simulation for extended fuel design guideline. This facility is designed and developed to provide out-pile fuel data for accident analysis model and fuel licensing. Functional tests of FAMeCT were performed to confirm functionality, structural integrity, and validity of newly-built fuel assembly mechanical test facility. Test program includes signal check of data acquisition system, load delivering capacity using real-sized fuel assemblies and a standard loading cylindrical rigid specimen. Fuel assembly's lateral bending test was carried out up to 30 mm of pull-out displacement. Limit case axial compression loading test up to 33 kN was performed to check structural integrity of UCPS (Upper Core Plate Simulator) support frame. Test results show that all test equipment and measurement system have acceptable range of alignment, signal to noise ratio, load carrying capacity limit without loss of integrity. This paper introduces newly constructed fuel assembly's mechanical test facility and summarizes results of functional test for the mechanical test equipment and data acquisition system.

• 한국소음진동공학회논문집
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• 제16권2호
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• pp.163-168
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• 2006

The PWR Nuclear Fuel assembly consists of more than 250 fuel rods that are supported by leaf springs in the cells of more than 10 Spacer Grids (SG) along the rod length. Since it is not easy to conduct mechanical tests on a full-scale model basis, the small-scaled rod bundle $(5\times5)$ which is called partial fuel assembly is generally used for various performance tests during the development stage. As one of the small-scaled tests, a flow test should be carried out in order to verify the performance of the spacer grid to obtain the Flow-Induced Vibration (FIV) characteristics of the scaled fuel assembly over the specified flow range. A vibration test should be also performed to obtain the modal parameters of the assembly prior to the flow test. In this study, we want to develop the estimation procedure of the damping ratio for the scaled test assembly. For the damping factor of the partial fuel assembly and the grid cage at the first vibration mode, as one of the vibration tests, a so-called pluck testing has been performed in air as a preliminary test prior to in-flow damping measurement test. Logarithmic decrement method is used for calculation of the damping ratio. Estimated damping ratio of the partial fuel assembly is about $0.7\%$ with reasonable error of $2\%$ for the previous results. Nonlinear behavior of the partial fuel assembly might be stem mainly from the rod-grid support configuration.

• Nuclear Engineering and Technology
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• 제38권4호
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• pp.375-382
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• 2006

Characterization tests (load vs. displacement curve) are conducted for the springs of Zirconium alloy spacer grids for an advanced LWR fuel assembly. Twofold testing is employed: strap-based and assembly-based tests. The assembly-based test satisfies the in situ boundary conditions of the spring within the grid assembly. The aim of the characterization test via the aforementioned two methods is to establish an appropriate assembly-based test method that fulfills the actual boundary conditions. A characterization test under the spacer grid assembly boundary condition is also conducted to investigate the actual behavior of the spring in the core. The stiffness of the characteristic curve is smaller than that of the strap-wised boundary condition. This phenomenon may cause the strap slit condition. A spacer grid consists of horizontal and vertical straps. The strap slit positions are differentiated from each other. They affords examination of the variation of the external load distribution in the grid spring. Localized legions of high stress and their values are analyzed, as they may be affected by the spring shape. Through a comparison of the results of the test and FE analysis, it is concluded that the present assembly-based analysis model and procedure are reasonably well conducted and can be used for spring characterization in the core. Guidelines for improving the mechanical integrity of the spring are also discussed.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회A
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• pp.1854-1858
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• 2007

The reliability assurance with respect to the test procedure and results of the out-pile mechanical performance test for the nuclear fuel assembly is an essential task to assure the test quality and to get a permission for fuel loading into the commercial reactor core. For the case of vibration test, which is carried out to obtain basic dynamic characteristics of the fuel assembly, proper management and appropriate calibration of instruments and devices used in the test, various efforts to minimize the possible error during the test and signal acquisition process are needed. Additionally, the deep understanding both of the theoretical assumption and simplification cation for the signal processing/modal analysis and of the functions of the devices used in the test were highly required. Finally, to verify the test result to represent the accurate natural characteristics of the structure, the proper correlation analysis between the theoretical and experimental method has to be carried out. In this study, the overall procedure and result of lateral vibration test for the fuel assembly's mechanical characterization were briefly introduced. A series of measures to assure and improve the reliability of the vibration test were discussed.

• 대한기계학회논문집
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• 제18권12호
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• pp.3395-3403
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• 1994

The structural test technique and equipment for strength test of astronautical structures, such as rocket, were presented in this paper. Structural strength tests of the fin assembly with fin and fin frame in the scientific sound rocket were performed with load levels of 100% limit load and 150% ultimate load of design lift force. Safety factors in each part of the fin assembly were calculated at these two load levels and the stiffnesses based on the measured deflection of fin assembly and strains on fin and fin frame were evaluated at these two load level. As the result of structural test, the fin assembly was estimated to be safe.

• Industrial Engineering and Management Systems
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• 제10권2호
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• pp.161-169
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• 2011

In seeking further efficiency in production preparation, it is common to examine assembly sequences using digital manufacturing. The assembly sequences affect the product evaluation, so it is necessary to test several assembly sequences before actual production. However, because selection and testing of assembly sequences depends on the operator's personal experience and intuition, only a small number of assembly sequences are actually tested. Nevertheless, there is a systematic method for generating assembly sequences using a contact-related figure. However, the larger the number of parts, the larger the number of assembly sequences geometric becomes. The purpose of this study is to establish a systematic method of generating efficient assembly sequences regardless of the number of parts. To generate such assembly sequences selectively, a "Tournament Tree," which shows the structure of an assembly sequence, is formulated. Applying the method to assembly sequences of a water valve, good assembly sequences with the same structure as the Tournament Tree are identified. The structure of such a Tournament Tree tends to have fewer steps than the others. As a test, the structure is then applied for a drum cartridge with 38 parts. In all the assembly sequences generated from the contact-related figures, the best assembly sequence is generated by using the Tournament Tree.

• 시스템엔지니어링학술지
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• 제2권1호
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• pp.37-41
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• 2006

The KSLV-I satellite launch vehicle will be launched in a space center currently under construction. The Space Center which is an advance post base of space development of Korea is located on Oenaro island in Kohung, South Cholla Province. A Ground Complex of the Space Center consists of an AC(Assembly Complex), a LC(Launch Complex), and a MCC(Mission Control Center). Assembly and test facilities are located in the AC in which stage assembly, integrated assembly, check-up, certification test, and pre-launch test are made effectively. A launch pad, fuel supply facilities, a launch control center and associated supporting facilities are located in the LC, and the MCC has control over the space center. These ground complex facilities have diverse forms of an interface with mechanical device, electric device, and etc. These should also provide optimum condition and performance during launch operation processes of the launch vehicle. This paper introduces the result of R&D for the AC of the ground complex performed during system design period.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회A
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• pp.30-34
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• 2008

The transfer assembly (or transfer printing) technique is a promising method for fabricating multi-scale structures on various substrates including semiconductors and polymers, and has been applied to fabrication of flexible devices with superior performance to conventional organic flexible devices. The mechanical behaviors of the structures fabricated by the transfer assembly is a very important information for design and reliability evaluation purpose, but the measurement of the behaviors is difficult since their critical-dimensions are very tiny. In this study, Au films with nano-scale thickness were fabricated on a silicon substrate and their mechanical properties were measured using micro-tensile test. The Au films on the silicon substrate were then transferred to a PDMS substrate using the transfer assembly technique. Self-assembled monolayer (SAM) with a thiol group was used to enhance the transfer of Au films, and the mechanical behaviors were characterized using wrinkle-based test. The test results from micro-tensile and wrinkle-based test are compared to each other, and their implication to the transfer assembly technique is discussed.

• Journal of the Korean Wood Science and Technology
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• 제10권3호
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• pp.118-131
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• 1982

1. 이 연구(硏究)는 Yale대학교(大學校) 임과대학목재이학교실(林料大學木材利學敎室)에서 최근(最近) 새로히 쓰기 시작(始作)한 phenolic resin의 일종(一種)과 soy-bean glue 1auxein 10-B에 대(對)하여 assembly time의 변동(變動)이 제작(製作)된 합판(合板) shear strength에 어떠한 영향을 주는가를 알고 또한 그의 비교적(比較的) 적당(適當)한 실질적(實質的)인 assembly time의 범위를 결정(決定)하기 위하여 실시(實施)된 것이다. 2. 이 연구(硏究)에서 쓴 단판은 동실험실(同實驗室)에 실험용재료(實驗用材料)로 비치(備置)된 1/22in. 너도 밤나무(beech) 단판을 사용(使用)하였으며 수지는 phenolic resin U.S.P. low temperature liguid resorcinol type 와 Lauxein No. 10-B cold press water - resistant soygule 등으로 실험용(實驗用) sample을 구입(購入)하여 사용(使用)하였다. 3. 실험용(實驗用) ply-wood는 삼합식(三合式)으로 실험(實驗)을 하게 된 assembly time의 variation은 일분(一分)에서 시작(始作)하여 5, 10. 15, 25, 35, 50, 70분(分)등으로 8개(個)의 variation이 있게 하고 assembly 법(法)으로는 open assembly와 closed assembly의 2법(法)으로 하였으며 제작(製作)된 ply-wood의 성질비교(性質比較)는 dry test와 wet test의 shear strength test를 통(通)하여 나타나는 shear strength와 목파율을 가지고 하였다. 4. assembly time의 variation에 따른 합판의 shear strength와 목파율은 Table 1. 2. 3. 4에 표시(表示)된 바와 같은 결과(結果)를 보였으며 phenolic resin을 갖이고 closed assembly 법(法)으로 제작(製作)된 합판의 wet test를 제외하고는 모두 assembly time이 증가(增加)됨에 따라 shear strength와 목파율은 감소(減少)되여 가는 경향(傾向)을 보이고 있다. 그리고 실질적(實質的)으로 유효(有效)한 assembly time의 범위는 다음 표(表)(8)과 같다. 5. 이 실험(實驗)을 하는 동안 친절(親切)한 충고(忠告)와 지도편달(指導鞭達)를 애끼지 않고 도와주신 Yale 대학교(大學校) 목재이용학교수(木材利用學敎授) Dr. F.F.Wangaard씨(氏)와 Prof. Hess a. 그리고 실험실(實驗室) 담임자(擔任者)인 Mr. Clanch씨(氏)에게 충심(衷心)으로 사의(謝意)를 표시(表示)한다.