Model Developments for Quantitative Estimates of the Benefits of the Signals on Nuclear Power Plant Availability and Economics

Seong, Poong-Hyun Korean Nuclear Society 1993 Nuclear Engineering and Technology Vol.25 No.3

원자력 발전소 운전원에게 발전소 상태를 정확히 알려주는 완벽한 신호가 원자력 발전소 전체의 가용도와 경제성에 얼마만한 영향을 주는가에 대한 정량적인 분석이 이 논문에서 수행되어졌다. 이 분석을 위한 기본 모델들이 개발되어졌고 이 모델들은 발전소가 정상상태에서 비정상상태로 바뀌어갈때 운전원이 발전소가 완전히 비정상상태로 가기전에 발전소를 정상상태로 회복시키는 것에 완벽한 발전소 신호가 얼마만큼 영향을 주는가를 정량화 하였다. 또한 이러한 완벽한 신호가 경제적으로 얼마만큼의 이득을 주는가도 정량화 하였다. 이 모델 적용의 대상으로는 응축 및 주급수 시스템을 선정하였다.

ADVANCED MMIS TOWARD SUBSTANTIAL REDUCTION IN HUMAN ERRORS IN NPPS

Seong, Poong Hyun,Kang, Hyun Gook,Na, Man Gyun,Kim, Jong Hyun,Heo, Gyunyoung,Jung, Yoensub Korean Nuclear Society 2013 Nuclear Engineering and Technology Vol.45 No.2

This paper aims to give an overview of the methods to inherently prevent human errors and to effectively mitigate the consequences of such errors by securing defense-in-depth during plant management through the advanced man-machine interface system (MMIS). It is needless to stress the significance of human error reduction during an accident in nuclear power plants (NPPs). Unexpected shutdowns caused by human errors not only threaten nuclear safety but also make public acceptance of nuclear power extremely lower. We have to recognize there must be the possibility of human errors occurring since humans are not essentially perfect particularly under stressful conditions. However, we have the opportunity to improve such a situation through advanced information and communication technologies on the basis of lessons learned from our experiences. As important lessons, authors explained key issues associated with automation, man-machine interface, operator support systems, and procedures. Upon this investigation, we outlined the concept and technical factors to develop advanced automation, operation and maintenance support systems, and computer-based procedures using wired/wireless technology. It should be noted that the ultimate responsibility of nuclear safety obviously belongs to humans not to machines. Therefore, safety culture including education and training, which is a kind of organizational factor, should be emphasized as well. In regard to safety culture for human error reduction, several issues that we are facing these days were described. We expect the ideas of the advanced MMIS proposed in this paper to lead in the future direction of related researches and finally supplement the safety of NPPs.

Development of Automatic Reactor Internal Vibration Monitoring System Using Fuzzy Peak Detection and Vibration Mode Decision Method

Hyun Gook Kang 한국원자력학회 1998 Nuclear Engineering and Technology Vol.30 No.1

A Dependability Modeling of Software Under Memory Faults for Digital System in Nuclear Power Plants

Jong Gyun Choi 한국원자력학회 1997 Nuclear Engineering and Technology Vol.29 No.6

Application of Smart Transmitter Technology in Nuclear Engineering Measurements

Kang, Hyun-Gook,Seong, Poong-Hyun Korean Nuclear Society 1993 Nuclear Engineering and Technology Vol.25 No.3

By making use of the microprocessor technology, instrumentation system becomes intelligent. In this study a programmable smart transmitter is designed and applied to the nuclear engineering measurements. In order to apply the smart transmitter technology to nuclear engineering measurements, the digital time delay compensation function and water level change detection function are developed and applied in this work. The time compensation function compensates effectively the time delay of the measured signal, but it is found that the characteristics of the compensation function should be considered through its application. It is also found that the water level change detection function reduces the detection time to about 7 seconds by the signal processing which has the time constant of over 250 seconds and which has the heavy noise.

Development of Automatic Reactor Internal Vibration Monitoring System Using Fuzzy Peak Detection and Vibration Mode Decision Method

Kang, Hyun-Gook,Seong, Poong-Hyun,Park, Heui-Youn,Lee, Cheol-Kwon,Koo, In-Soo Korean Nuclear Society 1998 Nuclear Engineering and Technology Vol.30 No.1

In this work a method to detect the vibrational peak and to decide the vibrational mode of detected peak for core internal vibration monitoring system which is particularly concerned on the core support barrel (CSB) and fuel assemblies is developed. Flow induced vibration and aging process in the reactor internals cause unsoundness of the internal structure. In order to monitor the vibrational status of core internal, signals from the ex-core neutron detectors are transformed into frequency domain. By analyzing transformed frequency domain signal, an analyst can acquire the information on the vibrational characteristics of the structures, i.e., vibration frequencies of each component, vibrational level, modes of vibration, and the causes of the abnormal vibration, if any. This study is focused on the development of the automated monitoring system. Several methods are surveyed to define the peaks in power spectrum and fuzzy theory is used to automatic detection of the vibrational peaks. Fuzzy algorithm is adopted to define the modes of vibration using the peak values from fuzzy peak recognition, phase spectrum, and coherence spectrum.

Development of a Real-Time Thermal Performance Diagnostic Monitoring System Using Self-Organizing Neural Network for KORI-2 Nuclear Power Unit

Kang, Hyun-Gook,Seong, Poong-Hyun Korean Nuclear Society 1996 Nuclear Engineering and Technology Vol.28 No.1

In this work, a PC-based thermal performance monitoring system is developed for the nuclear power plants. The system performs real-time thermal performance monitoring and diagnosis during plant operation. Specifically, a prototype for the KORI-2 nuclear power unit is developed and examined in this work. The analysis and the fault identification of the thermal cycle of a nuclear power plant is very difficult because the system structure is highly complex and the components are very much inter-related. In this study, some major diagnostic performance parameters are selected in order to represent the thermal cycle effectively and to reduce the computing time. The Fuzzy ARTMAP, a self-organizing neural network, is used to recognize the characteristic pattern change of the performance parameters in abnormal situation. By examination, this algorithm is shown to be able to detect abnormality and to identify the fault component or the change of system operation condition successfully. For the convenience of operators, a graphical user interface is also constructed in this work.

Fault-tolerance Performance Evaluation of Fieldbus for NPCS Network of KNGR

Jung, Hyun-Gi,Seong, Poong-Hyun Korean Nuclear Society 2001 Nuclear Engineering and Technology Vol.33 No.1

In contrast with conventional fieldbus researches which are focused merely on real-time performance, this study aims to evaluate the real-time performance of the communication system including fault-tolerant mechanisms Maintaining performance in presence of recoverable faults is very important in case that the communication network is applied to a highly reliable system such as next generation Nuclear. Power. Plant (NPP). If the tie characteristics meet the requirements of the system, the faults will be recovered by fieldbus recovery mechanisms and the system will be safe. If the time characteristics can not meet the requirements, the faults in the fieldbus can propagate to the system failure. In this study, for the purpose of investigating the time characteristics of fieldbus, the recoverable faults are classified and then the formulas that represent delays including recovery mechanisms are developed. In order to validate the proposed approach, we have developed a simulation model that represents the Korea Next Generation Reactor (KNGR) NSSS Process Control System (NPCS). The results of the simulation show us the reasonable delay characteristics of the fault cases with recovery mechanisms. Using the simulation results and the system requirements, we also can calculate the failure propagation probability from fieldbus to outer system.

유전 및 육종 : 초위성체 표지를 이용한 한국재래돼지 집단의 분자유전학적 고찰

연성흠 ( Seong Heum Yeon ),이승수 ( Seung Soo Lee ),조창연 ( Chang Yeon Cho ),진현주 ( Hyun Ju Jin ),유용희 ( Yong Hee Yoo ),이풍연 ( Poong Yeon Lee ),위미순 ( Mi Soon Wee ),고응규 ( Yeoung Gyu Ko ),손준규 ( Jun Kyu Son ) 한국동물자원과학회(구 한국축산학회) 2011 한국축산학회지 Vol.53 No.1

초위성체(MS) 표지를 이용하여 한국재래돼지 집단의 각각의 분자유전학적 특성을 조사하고 그 평가를 통해 한국재래돼지에 대한 품종 및 계통분류의 기초를 마련하고자 본 연구를 수행하였다. 또한, 각 재래돼지 집단 내 및 집단간의 유전적 변이성을 확인하고, 그 분류 및 특성평가를 위한 MS 분석체계를 마련하여 국내 가축유전자원 관리에 활용하고자 하였다. 국내 관리기관 및 농가에서 보유하고 있는 6개 재래돼지 집단을 중국의 4개 재래돼지 집단 및 외래종 돼지 7개 집단과 함께 분석하였다. 도합 17집단 648두를 대상으로 26개 MS 표지로 분석한 결과, 한국재래돼지 집단은 외래종과 중국재래돼지로부터 분자유전학적으로 별개의 집단으로 확연히 구분되는 것을 확인하였다. 한국재래돼지 집단의 기대이형접합도(HE)는 0.65의 값을 보인 두 집단(B, D)을 제외한 나머지에서 0.48~0.55의 수준을 보여 전반적으로 외래종에 비해 낮았다. 한국재래돼지 집단간의 유전거리 또한 0.12~0.34 정도로 비교대상에 비하여 낮았다. 분석대상 한국재래돼지 6집단 중 세 개의 집단은 높은 유전적 균일도를 보였으나, 두 집단에서는 일부 집단의 혼입을, 나머지 하나의 집단에서는 둘 이상의 집단으로부터의 복잡한 혼입이 의심되는 매우 낮은 유전적 균일도를 확인하였다. 본 연구를 통하여 한국재래돼지 집단간의 유전적 차이 및 동질성, 그리고 집단내의 유전적 균일성을 확인하였다. 이러한 결과는 국내유전자원의 고유성을 인정할 수 있는 과학적인 근거로서, 국가수준의 가축유전자원 평가, 관리의 기초자료로 활용될 수 있을 것이다. The study was conducted to select and optimize microsatellite(MS) markers for evaluation of Korean native pig(KNP) populations in order to provide standard for the classification and breed definition of the indigenous breeds. The study also aimed to characterize and classify each KNP populations. A total of 648 pigs from 17 pig populations including six KNP, four Chinese native pig and four commercial pig populations were analyzed with 26 MS markers. KNP populations formed separate cluster from those of Chinese native pig and introduced pig populations. Expected heterozygosity(He) of KNP populations were 0.48~0.55 except two populations with 0.65. Genetic distances between KNP populations were relatively shorter: 0.12-0.34. Among six KNP populations, three showed high genetic uniformity, two showed lower uniformity and one showed high level of impurity and heterozygosity. The results can be used to evaluate and manage animal genetic resources at national scale.

The Speed of Eating and Functional Dyspepsia in Young Women

( Dong Hyun Sinn ),( Dong Hyuk Shin ),( Seong Woo Lim ),( Kyung Mook Kim ),( Hee Jung Son ),( Jae J. Kim ),( Jong Chul Rhee ),( Poong Lyul Rhee ) 대한소화기기능성질환·운동학회 2010 Gut and Liver Vol.4 No.2

Background/Aims: Little information is available on whether the speed of eating differs between individuals with and without dyspepsia, mainly because controlled studies are usually not feasible. Methods: A survey was applied to 89 individuals with relatively controlled eating patterns, using questionnaires that assessed eating time and functional dyspepsia (FD) based on the Rome III criteria. Results: The prevalence of FD was 12% (11 of 89 participants), and 7% (6 of 89) were diagnosed with gastroesophageal reflux disease (GERD). The proportion of individuals reporting that they ate their meals rapidly was higher for those with FD than for those without FD or GERD (control) (46% vs 17%, p=0.043), as was the reported eating speed (7.1±1.5 vs 5.8±2.0 [mean±SD], p=0.045; visual analog scale on which a higher score indicated faster eating). However, the measured eating time did not differ significantly between FD and controls (11.0±2.8 vs 12.8±3.3 minutes, p=0.098). The proportion of individuals who ate their meals within 13 minutes was significantly higher for those with FD than for controls (91% vs 51%, p=0.020). Conclusions: The results of this study suggest that eating speed affects dyspepsia. Further studies are warranted. (Gut Liver 2010;4:173-178)