The Performance Evaluation of NSSS Control Systems for UCN 4

Sohn, Suk-Whun,Song, In-Ho,Sohn, Jong-Joo,Park, Jong-Ho,Seo, Jong-Tae Korean Nuclear Society 2001 Nuclear Engineering and Technology Vol.33 No.3

NSSS Control Systems automatically mitigate transient conditions and leads to a stable plant condition without operator actions when a transient occurs during normal power operation. In this paper, the function and performance of NSSS control systems were examined and evaluated by comparing the predicted results with the measured data for the selected events. Loss of a Main Feedwater Pump and Load Rejection to House Load Operation events were selected for the evaluation among the transient tests peformed during the Power Ascension Test (PAT) of UCN unit 4. The overall schematic control actions of NSSS control systems can be evaluated easily through the observation of these two typical events. The selected events were analyzed by the KISPAC computer code[l] which had been used in developing the control logic and determining the control setpoints during the plant design. Additionally, the performance of FWCS during low power operation was evaluated. The result of evaluation showed that the NSSS control systems were designed properly and the performance of the NSSS control systems was excellent and also the computer code had a good prediction capability.

Numerical Analysis on Letdown System Performance Test for YGN 3

Ho Taek Seo 한국원자력학회 1997 Nuclear Engineering and Technology Vol.29 No.2

The impact of sleep apnoea syndrome on nocturia according to age in men

Kang, Suk‐,Hoon,Yoon, In‐,Young,Lee, Sang Don,Kim, Jeong‐,Whun Blackwell Publishing Ltd 2012 BJU INTERNATIONAL Vol.110 No.c11

<P>Study Type – Symptom prevalence (cohort)</P><P>Level of Evidence 2b</P><P><B>What's known on the subject? and What does the study add?</B></P><P>Sleep apnoea syndrome (SAS) can be a risk factor for nocturia, although whether the relationship between nocturia and SAS changes according to age remains to be addressed.</P><P>SAS has a modest impact on nocturia frequency and the prevalence of pathological nocturia in young adults and middle‐aged men. However, SAS may not be a risk factor for nocturia in the elderly, and age‐related urinary diseases and voiding dysfunctions could over‐ride the influence of SAS on nocturia in the elderly.</P><P><B>OBJECTIVE</B></P><P><P>To assess the association between nocturia and sleep apnoea syndrome (SAS) according to age, as well as to determine the factors related to nocturia.</P></P><P><B>PATIENTS AND METHODS</B></P><P><P>A total of 1757 men who had been referred to a sleep laboratory underwent polysomnography.</P><P>Nocturia frequency was assessed using a questionnaire, and pathological nocturia was defined as the need to void two or more times per night.</P><P>The Pittsburgh Sleep Quality Index (PSQI) and Beck Depression Inventory (BDI) were applied to all study subjects.</P></P><P><B>RESULTS</B></P><P><P>Nocturia frequency was significantly correlated with age (<I>r</I>= 0.405, <I>P</I> < 0.001) and the apnoea–hypopnoea index (AHI) (<I>r</I>= 0.065, <I>P</I> < 0.01).</P><P>In those men aged <65 years, significant correlations were found between nocturic frequency and age, AHI, BDI and PSQI.</P><P>Multiple regression analysis showed that age (β= 0.303, <I>P</I> < 0.001), AHI (β= 0.107 <I>P</I> < 0.001) and benign prostatic hypertrophy (BPH; β= 0.069, <I>P</I> < 0.01) were associated with nocturia, and that the presence of pathological nocturia was predicted by BPH (odds ratio [OR], 2.77; <I>P</I> < 0.01), age (OR, 1.09; <I>P</I> < 0.001) and AHI (OR, 1.02; <I>P</I> < 0.001).</P><P>However, in men aged >65 years, nocturia frequency was significantly associated with BDI and PSQI, although no relationship was found between nocturia frequency and SAS parameters.</P><P>BPH was more frequently observed in elderly men with pathological nocturia than in those without pathological nocturia (OR, 2.18; <I>P</I> < 0.05).</P></P><P><B>CONCLUSIONS</B></P><P><P>In the elderly, SAS may not be a risk factor for nocturia.</P><P>Age‐related urinary diseases and voiding dysfunction may over‐ride the influence of SAS.</P></P>

후천성 면역결핍 증후군(AIDS) 환자에서 병발한 B세포 림프종파 초기 Kaposi 육종 1예

한원석,박병순,서대헌,조광현,은희철,성명훈,오명돈,최강원 대한감염학회 1999 감염 Vol.31 No.3

Obase : 객체지향 데이타베이스 관리 시스템

유석인(Suk I. Yoo),홍은지(Eunji Hong),이영훈(Young-Whun Lee),박현주(Hyunju Park),이주흥(Ju-Heung Lee),전용석(Yong S. Jun),김태권(Tae Gwon Kim),장혜진(Hai Jin Chang) 한국정보과학회 1994 정보과학회논문지 Vol.21 No.10

최근에 새로운 데이타베이스 응용 분야들을 개발하기 위해 객체지향 데이타 모델과 이를 기반으로 하는 객체지향 데이타베이스 관리 시스템들이 등장하였다. 본 논문에서는 이러한 연구 추세와 기존의 객체지향 데이타베이스 시스템들에 대한 분석을 기반으로 새로운 객체지향 데이타베이스 관리 시스템인 Obase의 설계 및 구현을 제시한다. Obase는 C++ 언어의 객체 모델을 확장한 데이타 모델을 기반으로 객체지향 개념들을 지원하고 데이타베이스 관리 기능들과 새로운 응용 분야에서 필요로 하는 기능들을 제공한다. 특히, Obase는 정적인 수정 탐지, 지속적 이름 관리, 정적인 타입 검사 환경에서의 스키마 변화 관리 등의 진보된 기능들을 제공한다. In recent years the object-oriented data models and the object-oriented database management systems have been introduced to support advanced database applications. Based on those introduced data models and systems, this paper presents a new object-oriented database management system, called the Obase, which has been developed using the extended object data model of the C++ language. The Obase supporting object-oriented concepts provides all functionalities necessary for the conventional database management as well as some advanced functionalities such as static update detection, persistent name management, and schema evolution under static type checking.

객체지향 질의어의 설계

이영훈(Young-Whun Lee),유석인(Suk I.Yoo) 한국정보과학회 1994 정보과학회논문지 Vol.21 No.6

많은 객체지향 데이타베이스 시스템들은 선언적인 질의어대신 절차적인 객체지향 데이타베이스 프로그래밍 언어에 의해 객체를 순항적으로 접근함으로서 데이타베이스를 검색하고 있다. 본 논문은 이러한 절차적인 언어에 의존하지 않고 데이타베이스를 검색할 수 있는 객체지향 질의어, OQL++(Object Query Language++)를 제시한다. OQL++는 객체들의 집합을 질의 단위로 하여 다양한 형태의 중첩 질의, 경로 수식, 집합 연산을 제공하며, 복합 객체, 객체 식별성, 클래스, 클래스 계층, 클래스 구성 계층, 메쏘드, 캡슐화 등의 객체지향 규준을 지원한다. 또한 질의 결과는 객체 이름에 의해 지속성을 부여받는다. In most object-oriented database systems, database retrievals are made through navigational accesses of objects by procedural object-oriented database programming languages instead of declarative query languages. In this paper, we present a new object-oriented query language, referred to as OQL++(Object Query Language++), by which database retrievals are made nonprocedurally it deals with collections of objects and provides a variety of nested query forms, path expressions, and set operations. It supports object-oriented paradigm, such as complex object, object identity, class, class hierarchy, class composition hierarchy, method, and encapsulation. Furthermore, results of queries can be made persistent through object names.

객체지향 데이타베이스 시스템에서의 의미적 질의 최적화

이영훈(Lee Young Whun),유석인(Suk I. Yoo) 한국정보과학회 1995 정보과학회논문지 Vol.22 No.6

객체지향 데이타베이스 시스템에서의 질의는 서브클래스 관계성, 참조 관계성, 객체 식별자등의 객체지향 규준이 표현되는 복잡한 객체 질의이다. 이러한 객체 질의에 대한 의미적 질의 최적화 기법의 적용에 대한 필요성은 증대되고 있으나, 이에 대한 연구는 미진하다. 본 논문에서는 객체지향 데이타베이스에서의 의미적 제약조건의 표현과 전파에 대해 고찰하고, 이를 기반으로 객체 질의를 위한 의미적 질의 최적화 기법을 제시한다. 매우 큰 질의 탐색 공간에 대해서 유용한 의미적 질의 변환을 유도하는 변환 휴리스틱들을 제시한다. 또한 객체 질의 최적기 원형 MagicVol을 사용하여 제시된 의미적 질의 최적화 기법의 유용성을 입증한다. Semantic query optimization becomes more important in OODB systems where object queries are complex due to presence of the object-oriented concepts such as subclassing relationship, is-part-of relationship, and object-identifier. However, there are few research works on them. In this paper we investigate the representation and propagation of semantic constraints and present a semantic query optimization technique for object queries. We also develop new transformation heuristics which guide useful transformations in the search space for semantic transformations of object queries. Using an object query optimizer prototype MagicVol, we conduct preliminary optimization experiments to verify that our semantic query optimization techniques are reasonable and useful.

Loss of a Main Feedwater Pump Test Simulation Using KISPAC Computer Code

Jeong, Won-Sang,Sohn, Suk-Whun,Seo, Ho-Taek,Seo, Jong-Tae Korean Nuclear Society 1996 Nuclear Engineering and Technology Vol.28 No.3

Among those tests performed during the Yonggwang Nuclear Power Plant Units 3 and 4 (YGN 3&4) Power Ascension Test period, the Loss of a Main Feedwater Pump test at l00% power is one of the major test which characterize the capability of YGN 3&4. In this event, one of the two normally operating main feedwater pumps is tripped resulting in a 50% reduction in the feedwater flow. Unless the NSSS and Turbine/Generator control systems actuate properly, the reactor will be tripped on low SG water level or high pressurizer pressure. The test performed at Unit 3 was successful by meeting all acceptance criteria, and the plant was stabilized at a reduced power level without reactor trip. The measured test data for the major plant parameters are compared with the predictions made by the KISPAC computer code, an updated best-estimate plant performance analysis code, to verify and validate its applicability. The comparison results showed good agreement in the magnitude as well as the trends of the major plant parameters. Therefore, the KISPAC code can be utilized for the best-estimate nuclear power plant design and simulation tool after a further verification using other plant test data.

Changes of Specifc Activity and Regulation of Nitric Oxide Synthase during Liver Regeneration after Partial Hepatectomy

(Hyang Woo Lee),(Dong Wan Seo),(Suk Woo Nam),(Young Jin Lee),(Dae Seok Sung),(Jung Whan Han),(Sung Whun An),(Young Kwun Ko) 한국응용약물학회 1996 학술대회 Vol.1996 No.1

음성신호와 전기성문파를 이용하는 새로운 매개변수 ; 성대 폐쇄 지연비율(Glottal Closure Delay Ratio)

최종민,권택균,정은정,이명철,김광현,성명훈,박광석,Choi, Jong-Min,Kwon, Tack-Kyun,Jung, Eun-Jung,Lee, Myung-Chul,Kim, Kwang-Hyun,Sung, Myung-Whun,Park, Kwang-Suk 대한후두음성언어의학회 2007 대한후두음성언어의학회지 Vol.18 No.1

Background and Objectives: Biomedical signals have been usually used for the diagnosis of the laryngeal function such as speech, electroglottograph(EGG), airflow and other signals. But, in most cases these signals were analysed separately. Here, we propose a new interchannel parameter Glottal Closure Delay Ratio(GCDR) which is estimated from speech and EGG measured simultaneously. Materials and Method: Speech and EGG signal were recorded simultaneously from 13 normal subjects, 39 patients. The patients' data included 16 polyps and 23 vocal folds palsy. Time difference between glottal closing instance on EGG and the first maximum peak on speech in a pitch period was calculated. Glottal closing instance was defined as the maximum peak on the first derivative of EGG signal(dEGG). Results: The standard deviation and jitter were calculated using 20-30 GCDRs extracted from each data, and they are significant different between normal and vocal fold paralysis group. Conclusion: The GCDR may be the first index reflecting speech and EGG characteristics and the perturbation of this parameter was significant different between normal and vocal fold paralysis group.