• 한국윤활학회:학술대회논문집
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• 한국윤활학회 2000년도 제31회 춘계학술대회
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• pp.159-165
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• 2000

In this paper the residual stresses on lubricated sliding surfaces were measured during break-in procedure and up to scuffing by the X-ray diffraction method. The cylinder-on-disk type tribometer was used with the line-contact geometry. Scuffing tests were done using a constant load. In the break-in procedure the loads were increased from very low values in several steps. It was found that the sliding surfaces with break-in represented relatively higher values of residual compressive stresses than those without break-in. The residual stresses below the surfaces showed the small amount of stress increases. The results of scuffing tests with and without break-in showed the same trends as break-in tests did. However, in case of tests with break-in procedure the stresses below the surfaces showed very large increases in the residual compressive stresses. From the tests of break-in and scuffing, it was found that the increases in scuffing lives were related with the increases of residual stresses on the lubricated sliding surfaces with break-in.

• Tribology and Lubricants
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• 제16권3호
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• pp.182-187
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• 2000

In this paper the residual stresses on lubricated sliding surfaces were measured during break-in procedure and up to scuffing by the X-ray diffraction method. The cylinder-on-disk type tribometer was used with the line-contact geometry. Scuffing tests were done using a constant load. In the break-in procedure the loads were increased from very low values in several steps. It was found that the sliding surfaces with break-in represented relatively higher values of residual compressive stresser than those without break-in. The residual stresses below the surfaces showed the small amount of stress increases. The results of scuffing tests with and without break-in showed the same trends as break-in tests did. However, in case of tests with break-in procedure the stresses below the surfaces showed very large increases in the residual compressive stresses. From the tests of break-in and scuffing, it was found that the increases in scuffing lives were related with the increases of residual stresses on the lubricated sliding surfaces with break-in.

• 한국음향학회지
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• 제26권8호
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• pp.403-408
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• 2007

대용량 코퍼스를 이용하는 합성단위 선택(unit selection) 기반 합성기에서 break는 자연성 및 명료성에 큰 영향을 미치는 파라미터로 unit selection 과정에서 음소 정보와 함께 중요한 특징으로 사용된다. 일본어는 피치의 상대적 높낮이로 표현되는 악센트를 가지는 언어이고, 악센트의 변화에 따라 AP(Accentual Phrase)가 결정되고 AP 경계에서 break가 형성된다. break는 규칙 기반 방식이나 통계적 방식인 J-ToBI를 이용하여 예측 할 수 있으나 다양성으로 인해 정확한 예측이 어렵다. 따라서 본 논문에서는 다양한 운율 정보를 포함하고 있는 대용량 코퍼스의 장점을 이용하기 위해 break를 고정 break와 유동 break로 나누어 합성단위 검색을 수행한다. 실험 결과 제안한 합성단위 선택 방법으로 합성음의 자연성을 향상 시킬 수 있었다.

• Nuclear Engineering and Technology
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• 제49권5호
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• pp.968-978
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• 2017

Three small-break loss-of-coolant accident (SBLOCA) tests with safety injection pumps were carried out using the integral-effect test loop for SMART (System-integrated Modular Advanced ReacTor), i.e., the SMART-ITL facility. The types of break are a safety injection system line break, shutdown cooling system line break, and pressurizer safety valve line break. The thermal-hydraulic phenomena show a traditional behavior to decrease the temperature and pressure whereas the local phenomena are slightly different during the early stage of the transient after a break simulation. A safety injection using a high-pressure pump effectively cools down and recovers the inventory of a reactor coolant system. The global trends show reproducible results for an SBLOCA scenario with three different break locations. It was confirmed that the safety injection system is robustly safe enough to protect from a core uncovery.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2008년도 하계종합학술대회
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• pp.983-984
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• 2008

This paper proposes a variable break that can offset prediction error as well as a pre-selection methods, based on the variable break, for enhanced unit selection. In Japanese, a sentence consists of several APs (Accentual phrases) and MPs (Major phrases), and the breaks between these phrases must predicted to realize text-to-speech systems. An MP also consists of several APs and plays a decisive role in making synthetic speech natural and understandable because short pauses appear at its boundary. The variable break is defined as a break that is able to change easily from an AP to an MP boundary, or from an MP to an AP boundary. Using CART (Classification and Regression Trees), the variable break is modeled stochastically, and then we pre-select candidate units in the unit-selection process. As the experimental results show, it was possible to complement a break prediction error and improve the naturalness of synthetic speech.

• 한국음향학회지
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• 제28권2호
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• pp.155-163
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• 2009

Text-to-speech 시스템에서 입력 텍스트로부터 운율 정보를 생성하기 위해서는 운율구 경계, 음소 지속시간, 기본주파수 포락선 설정의 3가지 기본적인 모듈이 필요하다. Break 인덱스 (BI; Break Index)는 합성기에서 운율구의 경계를 나타내고, 자연스러운 합성음을 생성하기 위해서는 BI를 정확히 예측하여야 한다. 그러나 BI는 문장의 의미나 화자의 읽기 습관(reading style)에 따라 임의적으로 결정되는 경우가 많아 정확한 예측이 매우 어렵다. 특히 일본어 합성기에서는 악센트 구 경계 (APB; Accentual Phrase Boundary)와 major phrase 경계 (MPB; Major Phrase Boundary)의 정확한 예측이 어렵다. 따라서 본 논문에서는 APB와 MPB 예측 오류를 보완할 수 있는 방법을 제안한다. BI를 고정 break (FB; Fixed Break)와 가변 break (VB; Variable Break)로 분류하여 합성단위 선택을 수행한다. 일반적으로 BI는 한번 생성되면 변하지 않는다. 따라서 BI가 잘못 생성된 경우 최적의 합성음을 생성할 수 없게 되는데, VB는 생성된 BI와 그것과 유사한 BI를 함께 이용하여 합성단위 선택을 수행함으로써 합성음의 BI가 생성된 BI와 다를 수 있는 것을 의미한다. APB와 MPB에 해당하는 BI에 대하여 VB인지 FB인지 CART(Classification and Regression Tree)를 이용하여 예측하고, VB인 경우 기본 주파수와 음소 지속시간에 대해 다중 운율 모델을 생성하여 합성단위 선택을 수행하였다. MOS 테스트 결과 원음이 4.99, 제안한 방법을 4.25, 기존의 방법은 4.01로 합성음의 자연성을 향상시킬 수 있었다.

• Nuclear Engineering and Technology
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• 제33권1호
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• pp.12-24
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• 2001

The post-LOCA long term cooling (LTC) performance of the Korean Standard Nuclear Power Plant (KSNPP) is analyzed for both small break loss-of-coolant accidents (LOCA) and large break LOCA at cold leg. The RELAP5/MOD3.2.2 beta code is used to calculate the LTC sequences based on the LTC plan of the Korean Standard Nuclear Power Plants (KSNPP). A standard input model is developed such that LOCA and the followed LTC sequence can be calculated in a single run for both small break LOCA and large break LOCA. A spectrum of small break LOCA ranging from \ulcorner.02 to 0.5 k2 of break area and a double-ended guillotine break are analyzed. Through the code calculations, the thermal-hydraulic behavior and the boron behavior are evaluated and the effect of the important action including the safety injection tank (SIT isolation and the simultaneous injection in LTC procedure is investigated. As a result, it is found that the sufficient margin is available in avoiding the boron precipitation in the core. It is also found that a further specific condition for the SIT isolation action need to be setup and it is recommended that the early initiation of the simultaneous injection be taken for larger break LTC sequences.

• The Journal of Korean Physical Therapy
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• 제31권3호
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• pp.147-150
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• 2019

Purpose: The purpose of this study was to compare the reliability of unilateral hip abductor strength assessment in side-lying with break and make test in subjects with pelvic drop. Hip abduction muscles are very important in the hip joint structures. Therefore, it is essential to evaluate their strength in a reliable way. Methods: Twenty-five subjects participated in this study. Unilateral isometric hip abductor muscle strength was measured in side-lying, with use of a specialized tensiometer using smart KEMA system for make test, of a hand held dynamometer for break test. Coefficients of variation, and intra class correlation coefficients were calculated to determine test-retest reliability of hip abductor strength. Results: In make test, maximal hip abductor strength in the side-lying position was significantly higher compared with break test (p<0.05). Additionally, Test-retest reliability of hip abductor strength measurements in terms of coefficients of variation (3.7% for make test, 16.1% for break test) was better in the side-lying position with make test. All intraclass correlation coefficients with break test were lower than make test (0.90 for make test, 0.73 for break test). Conclusion: The side-lying body position with make test offers more reliable assessment of unilateral hip abductor strength than the same position with break test. Make test in side-lying can be recommended for reliable measurement of hip abductor strength in subjects with pelvic drop.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1996년도 춘계학술발표회논문집(2)
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• pp.417-422
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• 1996

The KNGR has an advanced ECCS design feature which employs four mechanically-separated SI trains where each train consisting of one HPSI pump and one SIT injects ECC water directly into the reactor vessel downcomer annulus. To demonstrate that the KNGR ECCS design features meet the EPRI ALWR requirements of no core uncovery for a break of up to 6 inch diameter, small break LOCA cases with various break sizes were analyzed using a best-estimate analytical procedure. Two kinds of break locations are considered: cold leg and DVI line breaks. It was observed that the KNGR ECC design can tolerate a cold leg break of up to 10 inches with no core uncovery. However. since DVI line break with 6 inch diameter undergoes slight core uncovery. further investigation is required for KNGR SIS optimization.

• 상하수도학회지
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• 제16권6호
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• pp.710-716
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• 2002

A General Pipe Break Prediction Model that incorporates linear and exponential models in its form is developed. The model is capable of fitting pipe break trends that have linear, exponential or in between of linear and exponential trend by using a weighting factor. The weighting factor is adjusted to obtain a best model that minimizes the sum of squared errors of the model. The model essentially plots a best curve (or a line) passing through "cumulative number of pipe breaks" versus "break times since installation of a pipe" data points. Therefore, it prevents over-predicting future number of pipe breaks compared to the conventional exponential model. The optimal replacement time equation is derived by using the Threshold Break Rate equation by Loganathan et al. (2002).