• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2015년도 춘계 학술논문 발표대회
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• pp.13-14
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• 2015

To minimize construction of nuclear facility, it is required to reduce reinforcing bar amount and solve reinforcing bar concentration and for this, it is necessary to develop appication design technology and modular of high strength reinforcing bar. Hence, KHNP reduces excessive reinforcing bar amount which can cause possibility of poor construction of concrete through design standard development and modular of nuclear facility structure using high strength reinforcing bar to raise economics and has its purpose to maintain high-level safety and durability as they are. After reviewing the rebar drawing of the NPP structures and performing the mock-up test, the rebar modulation method in the various area of the NPP Structure has been established.

• 한국해안·해양공학회논문집
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• 제21권2호
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• pp.191-195
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• 2009

손상된 철근콘크리트 보를 모의하기 위해 사전균열을 발생시킨 후, GFRP Bar와 GSP 매입공법으로 보수하여 피로실험을 수행하였다. 피로실험 결과, 실험보는 피로하중 초기 싸이클에서 대부분의 잔류처짐과 균열이 발생하고 싸이클 수에 따른 이들의 증가율은 미미하였다. 보수보의 정적강도는 보수하지 않은 보에 비해 크게 증가하였지만, 피로강도는 감소하였다. S-N 곡선에서, GFRP Bar 보수보의 피로강도는 정적강도의 58%, GSP 보수보의 피로강도는 52%였다.

• Steel and Composite Structures
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• 제48권2호
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• pp.131-143
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• 2023

The CFRP bar was used to achieve more ductile and durable headed-stud shear connectors in composite components. Three series of push-out tests were firstly conducted, including specimens reinforced with pure steel fibers, steel and CFRP bars. The distributed stress was measured by the commercial PPP-BOTDA (Pre-Pump-Pulse Brillouin optical time domain analysis) optical fiber sensor with high spatial resolution. A series of numerical analyses using non-linear FE models were also made to study the shear force transfer mechanism and crack response based on the test results. Test results show that the CFRP bar increases the shear strength and stiffness of the large diameter headed-stud shear connection, and it has equivalent reinforcing effects on the stud shear capacity as the commonly used steel bar. The embedded CFRP bar can also largely improve the shear force transfer mechanism and decrease the tensile stress in the transverse direction. The parametric study shows that low content steel fibers could delay the crack initiation of slab around the large diameter stud, and the CFRP bar with normal elastic modulus and the standard reinforcement ratio has good resistance to splitting crack growth in headed stud shear connectors.

• 한국학교수학회논문집
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• 제14권1호
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• pp.85-100
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• 2011

중국 대학입학시험의 정식 명칭은 '보통고등학교초생전국통일고시식(普通高等學校初生全國統一考試)이며, 일반적으로 줄여서 '고시(高考)'라고 부른다. 고시(高考)는 고등학교 교육과정 내의 지식과 능력을 측정하는 시험으로 고등학교 졸업(예정자) 및 동등학력을 갖춘 학생이 치르는 선발고사라는 점에서 우리나라의 수능과 매우 유사하다. 이런 점에서 고시(高考)의 수학과 평가 내용 및 구성 고찰을 통해 수능 수리영역에 주는 발전적인 시사점을 도출하고자 한다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2001년도 춘계학술대회 논문집
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• pp.501-504
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• 2001

The use of error compensation techniques has been recognized as an effective way in the improvement of the accuracy of a machine tool. The laser measurement method for identifying position errors of machine tool has the disadvantages such as high cost, long calibration time and usage of volumetric error synthesis model. Accordingly, this paper deals with analysis of the position errors of a machine tool using ball bar test without using complicated error synthesis model. Statistical analysis method was adopted in this paper for deriving position errors using hemispherical helix ball bar test.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2000년도 춘계학술대회 논문집
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• pp.703-707
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• 2000

Machine tool errors have to be characterized and predicted to improve machine tool accuracy. A real-time error compensation system has been developed based on volumetric error synthesis model which is composed of machine tool errors. This paper deals with new algorithm about verification of machine tool errors. This new algorithm uses a simplified volumetric error synthesis model. This simplified model is constructed with only main components among the error components of the machines. This main error components are analyzed by three-dimensional helical ball bar test. By substituting result of helical ball bar test fer simplified model, we could find that obtained error components are closed to real error components.

• 한국정밀공학회지
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• 제19권9호
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• pp.34-40
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• 2002

Machining accuracy is affected by quasi-static errors of machining center. Since machine errors have a direct influence upon both the surface finish and geometric shape of the finished workpiece, it is very important to measure the machine errors and to compensate these errors. The laser measurement method for identifying geometric errors of machine tool has the disadvantages such as high cost, long calibration time and usage of volumetric error synthesis model. Accordingly, this paper deals with analysis of the geometric errors of a machine tool using ball bar test without using complicated error synthesis model. Statistical analysis method was adopted in this paper for deriving geometric errors using hemispherical helix ball bar test. As a result of experiment, geometric errors of the vertical machining center are compensated by 88%.

• 대한안전경영과학회지
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• 제14권3호
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• pp.167-174
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• 2012

In the manufacturing process the most widely used $\bar{X}$ chart has been applied to control the process mean. Also, Accelerated Life Test(ALT) is commonly used for efficient assurance of product life in development phases, which can be applied in production reliability acceptance test. When life data has lognormal distribution, through censored ALT design so that censored ALT data has asymptotic normal distribution, $ALT\bar{X}$ control chart integrating $\bar{X}$ chart and ALT procedure could be applied to control the mean of process in the manufacturing process. In the situation that process variation is controlled, $Z_p$ control chart is an effective method for the very small fraction nonconforming of quality characteristic. A simultaneous control scheme with $ALT\bar{X}$ control chart and $Z_p$ control chart is designed for the very small fraction nonconforming of product lifetime.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2009년도 춘계학술대회 논문집
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• pp.37-40
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• 2009

본 연구에서는 케로신/과산화수소 점화용 분사기의 설계/제작하여 분무특성에 관한 연구를 수행하고자 하였으며, 이에 앞서 촉매점화방식으로 적용할 때 가장 적합한 분사기를 설계하고자 하였다. 설계/제작된 분사기를 수류시험을 통해 질량 유량 및 분산각을 측정하였다. 그 결과 케로신의 목표 질량유량(12.88 g/s)은 설계 차압과 같은 차압인 3 bar에서 측정되었으며, 이 때 분산각은 $40^{\circ}$을 확인하였다. 또한 과산화수소의 목표 질량 유량(94.39 g/s)은 설계 차압(3 bar) 보다 작은 1 bar에서 측정됨을 확인하였다.

• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2003년도 가을 학술논문집
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• pp.544-548
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• 2003

바코드 라벨의 방사선 조사 시험은 방사성폐기물 용기에 부착할 바코드 라벨의 방사선 환경 하에서의 영향을 판단하기 위하여 수행하였다. 중$\cdot$저준위 방사성 폐기물은 원자력법에 의하면 총 방사능량이 4,000 Bq/g 미만을 말한다. 방사성 폐기물 용기의 외부에 부착할 바코드 라벨이 받게 되는 방사선 조사선량은 MCNP-4b Computer Code에 의하여 계산하였다. Co-60과 Cs-137 핵종들은 총 방사능에 50%씩 기여한다고 가정하였다. 용기와 바코드 라벨의 제원에 의하여 실제의 최종 방사선 조사선량을 계산하였다. 바코드 판독기를 이용하여 바코드 라벨의 인식률과 외관점검을 수행한 결과 코팅된 바코드 라벨은 중$\cdot$저준위 방사성 폐기물 용기에 사용하기에 적합하였다.