• Nuclear Engineering and Technology
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• v.45 no.7
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• pp.859-870
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• 2013

The paper summarizes the irradiation test and post-irradiation examination (PIE) data for the U-Mo low-enriched fuel that was irradiated in the MIR reactor under the RERTR Program. The PIE data were analyzed for both full-size fuel rods and mini-rods with atomized powder dispersed in Al matrix as well as with additions of 2%, 5% and 13% of silicon in the matrix and ZrN protective coating on the fuel particles. The full-size fuel rods were irradiated up to an average burnup of ${\sim}60%^{235}U$; the mini-rods were irradiated to an average burnup of ${\sim}85%^{235}U$. The presented data show a significant increase of the void fraction in the U-Mo alloy as the U-235 burnup rises from ~ 40% up to ~ 85%. The effect of irradiation test conditions and U-235 burnup were analyzed with regard to the formation of an interaction layer between the matrix and fuel particles as well as generation of porosity in the U-Mo alloy. Shown here are changes in distribution of U fission products as the U-235 burnup increases from ~ 40% up to ~ 85%.

• Journal of rehabilitation welfare engineering & assistive technology
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• v.4 no.1
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• pp.9-14
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• 2010

According to graying of population and income enlargement of people, interest about U-Healthcare of new form fusing with IT technology are enlarged. Need a estimation technology and standard of test method for safety and performance considering usage environment of U-Healthcare medical device. In this research, developed the standard of test method for usage environment safety and performance of U-Healthcare medical device referring IEC standards and KS standards.

• Journal of the Korean Data and Information Science Society
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• v.18 no.1
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• pp.195-210
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• 2007

This paper develops a consistent nonparametric test for Granger causality in the context of strong-mixing process, which covers a large class of stationary processes including ARMA and ARCH models. The previously proposed tests require absolute regularity ($\beta$-mixing) more stringent than the strong-mixing condition. We prove the consistency of the test under a high level assumption on the approximation error of U statistic by its projection. Due to the sample splitting, the test statistic we propose is asymptotically normally distributed under the null.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.42 no.1
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• pp.67-75
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• 2014

A full-scale static test for a composite structure small aircraft (KC-100) was conducted in the KARI. The test includes 15 full-scale test and 7 local test conditions. Test requirements with test schedule, test article with dummy structures, test load generation, test system, and equipment are introduced for the test. Test load data of the 1st test condition(U1) was analyzed to evaluate an accuracy of load control for the test. The analysis results show that load data obtained during test were within tolerance of Static Null Pacing Error(SNPE) and the error value of load control was 8.6N. The error of load controls for the full-scale static test using dozens of actuators was calculated by a method suggested by authors. Test data for all other test conditions is also shown in this paper. Finally, reactions measured from restraint system of the U1 test condition show that the reaction changes as load increment. The factors which may change the change of reactions for a full-scale static test are introduced in this study.

• Journal of Korean Association for Spatial Structures
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• v.21 no.2
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• pp.33-40
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• 2021

For the practical application of U-flanged Truss Hybrid beams, the flexural capacity of hybrid beams with end reinforcement details using vertical steel plates was verified. The bending test of U-flanged Truss Hybrid beams was performed using the same top chord under the compressive force, but with the thickness of the bottom plate and the amount of tensile reinforcement. The initial stiffness and maximum load of the specimen with tensile reinforcement have a higher value than that of the specimen without tension reinforcement, but the more tensile reinforcement, the greater the load decrease after the maximum load. In the case of the specimen with tensile reinforcement, because the test result value is 76% to 88% when compared with the flexural strength according to Korea Design Code, the safety of the U-flanged Truss Hybrid beam with the same details of the specimens can't ensure. Therefore, the development of new details is required to ensure that the bottom steel plate and the tensile reinforcement can undergo sufficient tensile deformation.

• The Journal of the Korea Contents Association
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• v.15 no.8
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• pp.579-587
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• 2015

The purpose of this study is to investigate how Korean learners perceive English vowels and further to test SLM which claims that new L2 vowel categories are more easily acquired than similar L2 vowel categories. Twenty Korean learners participated in English-to-Korean mapping test and English vowel identification test with target vowels /i, ɪ, u, ʊ, ɛ, æ/. The result revealed that Korean participants mapped the English pairs /i/-/ɪ/ and /u/-/ʊ/ onto single Korean vowel /i/ and /u/, respectively. in addition, both of English /ɛ/ and /æ/ were simultaneously mapped onto Korean /e/ and /ɛ/. This indicated that the Korean participants seemed to have perceptual difficulty for the pairs /i-ɪ/, /u-ʊ/, and /ɛ-æ/. The result of the forced-choice identification test showed that the accuracy of /ɪ, ʊ, æ/(ɪ: 81.3%, ʊ: 62.5%, æ: 60.0%) was significantly higher than that of /i, u, ɛ/(i: 28,8%, u: 28.8%, ɛ: 32.4%). Thus, the claim of SLM is confirmed given that /ɪ, ʊ, æ/ are new vowel categories whereas /i, u, ɛ/ are similar vowel categories. Further, the conspicuously low accuracy of the similar L2 vowel categories /i, u, ɛ/ was accounted for by over-generalization whereby the Korean participants excessively replaced L2 similar /i, u, ɛ/ with L2 new /ɪ, ʊ, æ/ as the participants were learning the L2 new vowel categories in the process of acquisition. Based on the findings this study, pedagogical suggestions are provided.

• Proceedings of the Korean Information Science Society Conference
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• 1998.10a
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• pp.591-593
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• 1998

DSM-CC U-U(User-to-User) 인터페이스는 다양한 광대역 멀티미디어 서비스 환경에서 멀티미디어 응용들을 제공하기 위하야 요구되는 동작들을 정의한 개방형 프로토콜이다. 본 연구에서는 DSM-CC U-U 인터페이스를 시험하기 위한 적합성 시험방법을 제시하고, 선택된 적합성 시험구조를 위한 접합성 추상시험항목들(Abstract Test Cases)을 도출한다.

• Nuclear Engineering and Technology
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• v.53 no.5
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• pp.1446-1453
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• 2021

In the past, several experimental investigations aiming at characterizing the natural circulation (NC) behavior in test facilities were carried out. They showed a variety of flow patterns characterized by an inverted U-shape of the NC flow curve versus primary mass inventory. On the other hand, attempts to reproduce such curves using thermal-hydraulic system codes, showed 10-30% differences between the measured and calculated NC mass flow rate. Actually, the used computer codes are generally based upon nodalization using single U-tube representation. Such model may not allow getting accurate simulation of most of the NC phenomena occurring during such tests (like flow redistribution and flow reversal in some SG U-tubes). Simulations based on multi-U-tubes model, showed better agreement with the overall behavior, but remain unable to predict NC phenomena taking place in the steam generator (SG) during the experiment. In the current study, the CATHARE code is considered in order to assess a NC characterization test performed in the four loops PKL facility. For this purpose, four different SG nodalizations including, single and multi-U-tubes, 1D and 3D SG inlet/outlet zones are considered. In general, it is shown that the 1D and 3D models exhibit similar prediction results up to a certain point of the rising part of the inverted U-shape of the NC flow curve. After that, the results bifurcate with, on the one hand, a tendency of the 1D models to over-predict the measured NC mass flow rate and on the other hand, a tendency of the 3D models to under-predict the NC flow rate.

• The Journal of the Korea Contents Association
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• v.16 no.1
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• pp.158-166
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• 2016

This study is a nonequivalent control group pre- and post-test design research whose purpose was to determine what effects the pre-operation provision of information has on the anxiety and uncertainty of mothers with a pre-school child of tonsillectomy and nursing satisfaction after the operation. Data were collected from mothers whose child underwent tonsillectomy at S general hospital. For the collection, those mothers were divided into the experimental and control groups, respectively consisting of 19 and 20 members. The experimental group was provided general education about the operation. In addition, they individually received information about the procedure that the researcher and an assistant provided on one-to-one basis for about 20 minutes, in which brochures containing the information were used. While, the control group was provided only general education as mentioned above. For data analysis, this study conducted ${\chi}^2$-test, Fisher's exact test and Mann-Whitney U-test. The pre-operation provision of information was found having brought significant differences between the control and experimental groups in their anxiety(U=104.5, p=.015) and uncertainty(U=83.5, p=.002) as well as their satisfaction after the operation(U=109.5, p=.022). The findings of this study strongly suggest that information provision before the operation is positively effective in reducing the anxiety and uncertainty of mothers with a tonsillectomy child and increasing their nursing satisfaction after the operation. These effects need to be more verified through repetitive and subsequent researches and by using many other methods of information provision.

• Journal of the Korean Society of Industry Convergence
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• v.9 no.4
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• pp.309-315
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• 2006

Important material properties of UCAS rod can divide by tension characteristic of base rod part and both end part of U type anchor. Tensile properties of base rod part need as concrete reinforcement material as an alternative material of reinforcing rod, and tensile properties of U type anchor is used at connection with UCAS rod. This treatise carry out tensile test of UCAS rod, examine necessary properties such as strength, elastic modulus and maximum capacity of UCAS rod as reinforcement material of concrete. Also, to examine material properties carry out tensile test of U type anchor.