• Computers and Concrete
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• v.13 no.1
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• pp.135-147
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• 2014

Strut-and-tie model (STM) has been recommended by many codes and standards as a rational model for discontinuity regions in structural members. STM has been adopted in ACI building code for analysis of reinforced concrete (RC) deep beams since 2002. However, STM recommended by ACI 318-11 is only applicable for analysis of ordinary RC deep beams. This paper aims to develop the STM for CFRP strengthened RC deep beams through the strut effectiveness factor recommended by ACI 318-11. Two sets of RC deep beams were cast and tested in this research. Each set consisted of six simply-supported specimens loaded in four-point bending. The first set had no CFRP strengthening while the second was strengthened by means of CFRP sheets using two-side wet lay-up system. Each set consisted of six RC deep beams with shear span to effective depth ratio of 0.75, 1.00, 1.25, 1.50, 1.75, and 2.00.The value of strut effectiveness factor recommended by ACI 318-11 is modified using a proposed empirical relationship in this research. The empirical relationship is established based on shear span to effective depth ratio.

• Journal of Institute of Control, Robotics and Systems
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• v.21 no.2
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• pp.137-144
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• 2015

In hybrid or electric vehicles, the hydraulic brake system must be controlled cooperatively with the traction motor for regenerative braking. Recently, a motor driven brake system with a PMSM (Permanent Magnet Synchronous Motor) has replaced conventional vacuum boosters to increase regenerative power. Unlike industry motor controls, additional source codes such as functional safety are essential in automotive applications to meet ISO26262 standards. Therefore, the control logic execution time increases, which also causes an extension of the motor current control period. The increased current control period makes precise motor current control challenging inhigh speed ranges where the motor is driven by high frequency. In this paper, a PWM update strategy and a time delay compensation method are suggested to improve current control and system performance. The proposed methods are experimentally verified.

• Journal of the Korean Society for Nondestructive Testing
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• v.30 no.4
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• pp.380-385
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• 2010

The integrity of components and piping of operating nuclear power plants has been identified by in-service inspection(ISI) requirements and activities commensurate with standards and codes such as KEPIC MI or ASME Code Section XI. However, the other various degradation mechanisms not considered during design stage of nuclear power plants have been checked by enhanced ISI. The requirements of enhanced ISI have been voluntarily developed by the industry itself or strickly issued by regulatory body. Even though the requirements were developed by the industry, they should be reviewed by regulatory body for their application in nuclear power plants. The enhanced ISI activities and requirements of non-destructive examination(NDE) which reflect the degradation issues in nuclear power industry will be primarily discussed in this paper.

• Journal of the Korean Institute of Gas
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• v.14 no.6
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• pp.44-50
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• 2010

Vibration responses of a centrifugal pump required dynamic analysis for seismic qualification, were calculated by using spectrum analysis, which is known to be very simple compared with time domain analysis. Modal analysis was performed and the results were utilized in the spectrum analysis. The vibration responses calculated from the spectrum analysis were more conservative than those from the time domain analysis, that is, the former can be used as safer in design process. The pump was qualified for the specified seismic service conditions as specified in IEEE 344-1987. The maximum stresses were less than allowable stress limits. Based on the analysis results, it is concluded that the pump meets all the dynamic requirements of the applicable codes, standards, and technical specification.

• Journal of the KSME
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• v.20 no.6
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• pp.457-467
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• 1980

가동중조사(ISI)에 적용되는 ASME-MI 의 1974년 Edition에 ISI시 검출된 흠함을 평가하는 절 차가 제시되었다는 것은 이미 언급한 바 있다. 가동중검사의 개념은 ASME-III에 따라 건설된 부품이라 하더라도 원자력발전소의 온 수명기간동안 또는 정해진 수명기간동안 재료 내부에 흠 함이 전혀 생기지 않는다거나 또는 성장하지 않는다고 볼 수 없다는데 에 근거를 둔 것이다. 즉, 부품을 건설할 때 ASME-III의 규정에 따라 수행한 비파괴시험(nondestructive examination)에 의하여 합격된 부품이라 할지라도 시험방법의 유효성 및 합격기준등에 의하여 발견되지 않았 거나, 발견되었더라도 합격된 흠합등이 있을 수 있다. 이러한 흠함들이 원자로의 가동과 더불어 성장하거나, 또는 부품의 사용조건에 따라 흠함이 새로이 발생할 경우는 RCPB의 구조적 건전성 및 안정성은 위협을 받게된다. 이에 대처하기 위하여 원자력발전소의 전수명기간의 통하여 정 기적으로 ISI를 수행해 줄 것이 10CFR50의 50, 55a, "Codes and Standards"에 법적으로 명문 화되어 있다. ISI 시발견된 흠함은 그 크기를 평가하여 합격기준을 초과하는 경우에는, 흠함의 제거(removal), 항리(repair), 부품의 대체(replacement), 또는 파괴력학적인 해석에 의하여 그러한 흠함이 구조건 안전성을 손상시키지 않는다는 것을 입증해 주어야 한다. ISI 시에 검출된 흠함을 평가하고 파괴력학적으로 해석하는 규정으로서 ASME-XI에 명시된 절차는 다음과 같다.차는 다음과 같다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.4
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• pp.457-465
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• 2021

This study analyzed the reality and problems of the defense standard classification system. This paper proposes a plan to perform standard management tasks efficiently through case analysis of domestic and foreign standard classification systems. To continuously solve the problem of military product quality in defense technical data, it is necessary to promptly reflect the civilian's excellent technology and benchmark the civilian standard system to manage high-quality defense standards. First, to analyze the reality, the NATO classification system was analyzed through the private KS of domestic and ICS codes, the US defense standard system of overseas. In the case of the Korean military, the reality of the defense standard classification system was grasped through the National Defense Standards Comprehensive System operated by the Defense Acquisition Program Administration. The classification of the ministry of defense's weapon system and force support system is the most suitable classification system for the Korean military, which is classified into eight weapon systems and six force support standard systems for all steps. Specifically, it was classified into 12 major categories, 66 categories, and 352 sub-categories. In this study, the establishment of the defense standard management system can improve the classification system of new defense standards by reflecting the superior technology of the private sector.

• Journal of the Korea Concrete Institute
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• v.22 no.3
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• pp.409-417
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• 2010

This paper discusses a series of experiments including material improvement in order to ensure quality of grouting for the post-tensioned structure. In prestressed concrete, grouting refers to the construction procedure of filling empty space of duct enclosing with strands using cementitious material, To date, adequate quality control of the grouting has not been established in Korea because the relationship between the grouting and durability of post-tensioned structure is not well-recognized. The Korean standard does not consider the important material characteristic, wick effect, which is caused by strands in the ducts and current standard testing method unlikely quantify reasonable material segregation. As a result, the grout material, which meets the current material standards, may exhibit excessive bleeding water or shrinkage during construction. In this study, international codes and standards related to grouting were surveyed. The ratio of constituents and novel admixtures were suggested to meet equivalently with these standards. Performance of this enhanced grout was compared to common domestic grout using the international standard testing method. A series of mock-up specimens considering geometry of PC beam was constructed and grout flow pattern was observed as the grout was injected. It was observed that the grouting performance was highly influenced by material properties and filling characteristic can be varied depending on geometry of ducts.

• Journal of the Korea Concrete Institute
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• v.22 no.3
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• pp.419-426
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• 2010

This paper discusses a series of experiments including material improvement in order to ensure quality of grouting for the post-tensioned structure. In presstressed concrete, grouting refers to the construction procedure of filling empty space of duct enclosing the prestress tendons using cementitious material, To date, adequate quality control of the grouting has not been established in Korea because the relationship between the grouting and durability of post-tensioned structure is not well-recognized. The Korean standard does not consider the important material characteristic, wick effect, which is caused by tendons in the ducts, and furthermore current standard testing method does not quantify reasonable material segregation. As a result, the grout material, which satisfies the current material standards, may well exhibit excessive bleeding of water or shrinkage during construction. In this study, international codes and standards related to grouting were surveyed. The mix proportions of the constituents and novel admixtures were suggested to meet equivalently with these standards. Performance of this enhanced grout was compared with common domestic grouts using the international standard testing method. A series of mock-up specimens considering geometry of PC beam was constructed and grout flow pattern was observed as the grout was injected. It was observed that the grouting performance was highly influenced by material properties and filling characteristic can be varied depending on geometry of ducts.

• The Journal of the Korea Contents Association
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• v.19 no.10
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• pp.217-225
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• 2019

National research and development(R&D) information is information generated in the process of performing R&D based on programs and projects issued by national government departments, and includes information from various research fields as ordered by various departments. Therefore, for efficient R&D information retrieval, it is necessary to build a national R&D terminology dictionary that can reflect the characteristics of such national R&D information. In this study, we propose a method for constructing a national R&D terminology dictionary by applying the classification of science and technology standards used to specify the research field in national R&D information. We will discuss the structural characteristics of national R&D project information and the usefulness of the project keyword, and explain the status of national R&D information by the National Standard Science and Technology Classification(NSSTC) Codes and the characteristics of the national R&D terminologies. Based on this, a method for building a national R&D terminology dictionary is defined in terms of the type and structure of the terminology dictionary, preliminary construction procedures, and refining rules. The national R&D terminology dictionary built on the basis of this study can be used in various ways such as expansion of search terms using Korean-English equivalent words and synonyms when searching national R&D information, clarifying the scope of search using NSSTC, and providing user convenience functions using term explanation information.

• Journal of Fashion Business
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• v.12 no.4
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• pp.56-72
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• 2008

The purpose of this study was to provide with the useful fundamental data by developing the appearl sizing system according to body types for the Women's Wear Specifications(GB/T 1335.2-1997), National Standards of People's Republic of China. Thus, it was to improve of the garment fit and coverage rate for the apparel production assortment and stock of exporting domestic clothing to China. For this study, 581 female women aged in their twenties who lived in Beijing and Shanghai were selected for the development of the apparel sizing system who resident in Beijing and Shanghai in China. As for the method of this study was made three primary items(length, bust girth, waist girth) and seven secondary items. Data analysis were processed by SPSS WIN 10.0 Program was used. The research selected 3 major body measurements, such as stature, bust girth, waist girth and 7 secondary measurements to investigate the body features of the Chinese adult women. The data throughout the study were analyzed by using SPSS WIN version 10.0 S/W. The result were as follows: The clothes dimensions for upper and lower body and the coverage rate of body size that had the highest appearance ratio from the selected age group in 20's were: Y-type 160-84 155-64(5.9%) and the section 160cm 22.6%, A-type 160-80 160-62(39%) and the section 160cm 27.9%, B-type 155-80 155-66(6.2%) and the section 160cm 24.7%. The representative size codes of the Chinese adult women aged in their 20's were set for representing certain body dimensions such as 150-76A 150-60A(0.0%), 155-80A 155-64A(2.4%), 160-84A 160-68A(3.9%), 165-88A 165-72A(0.3%), 170-92A 170-76A(0.0%). The production coverage rates for the each representative size codes were S size the section 150cm 1.5%, M size the section 155cm 15.3%, L size the section 160cm 36.0%, XL size the section 165cm 29.7%, XXL size the section 170cm 11.4% that covered 93.9%.