• Journal of the Korean Society of Safety
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• v.19 no.1
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• pp.23-30
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• 2004

Modern production systems are very complex by request of automation, and failure modes that occur in thisautomatic system are very various and complex. The efficient fault diagnosis for these complex systems is essential for productivity loss prevention and cost saving. Traditional fault diagnostic system which perforns sequential fault diagnosis can cause catastrophic failure during diagnosis when fault propagation is very fast. This paper describes the Real-time Intelligent Multiple Fault Diagnosis System (RIMFDS). RIMFDS assesses current machine condition by using sensor signals. This system deals with multiple fault diagnosis, comprising of two main parts. One is a personal computer for remote signal generation and transmission and the other is a host system for multiple fault diagnosis. The signal generator generates various faulty signals and image information and sends them to the host. The host has various modules and agents for efficient multiple fault diagnosis. A SUN workstation is used as a host for multiple fault modules and agents for efficient multiple fault diagnosis. A SUN workstation is used as a host for multiple fault diagnosis and graphic representation of the results. RIMFDS diagnoses multiple faults with fast fault propagation and complex physical phenomenon. The new system based on multiprocessing diagnoses by using Hierarchical Artificial Neural Network (HANN).

• The Mathematical Education
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• v.38 no.2
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• pp.145-157
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• 1999

Ability diagnosis is similar to medical diagnosis from a number of perspectives. However, a medical diagnosis is carried out by a direct observation through medical apparatuses, while an ability diagnosis is made by an indirect observation in the from of testing. In this respect, ability diagnosis is more difficult than medical diagnosis. Confined to middle school 1st year Mathematics, we collected survey data in 1996 from monthly tests. The data consist of student responses to diagnosis results on their abilities and of the effects of catch-up guidances for individual students which are provided based on their ability diagnosis outcomes. We analyzed the data and summarized the result in the paper. One of the main results is that the ability diagnosis as used in the paper has a very positive effect on catch-up study. But it is important to note that the effects vary across the ability groups, the effect appearing weaker in the lower ability group than in the higher ability group. This calls our attention to the need that the ability diagnosis and guidance for the catch-up study be differentiated among ability groups.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2008.04a
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• pp.425-430
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• 2008

To verify the system performance of portable AE leak diagnosis system which can measure with moving conditions, AE activities such as RMS voltage level, AE signal trend, leak rate degree according to AE database, FFT spectrum were measured during operation on total 11 valves of the secondary system in nuclear power plant. AE activities were recorded and analyzed from various operating conditions including different temperature, type of valve, pressure difference, valve size and fluid. The results of this field study are utilized to select the type of sensors, the frequency band for filtering and thereby to improve the signal-to-noise ratio for diagnosis for diagnosis or monitoring of valves in operation. As the final result of application study above, portable type leak diagnosis system by AE was developed. The outcome of the study can be definitely applied as a means of the diagnosis or monitoring system for energy saving and prevention of accident for power plant valve. The purpose of this study is to verify availability of the acoustic emission in-situ monitoring method to the internal leak and operating conditions of the major valves at nuclear power plants. In this study, acoustic emission tests are performed when the pressurized temperature water and steam flowed through glove valve(main steam dump valve) and check valve(main steam outlet pump check valve) on the normal size of 12 and 18 ". The valve internal leak monitoring system for practical field was designed. The acoustic emission method was applied to the valves at the site, and the background noise was measured for the abnormal plant condition. To improve the reliability, a judgment of leak on the system was used various factors which are AE parameters, trend analysis, frequency analysis, voltage analysis and amplitude analysis of acoustic signal emitted from the valve operating condition internal leak.

• Journal of Chest Surgery
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• v.29 no.3
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• pp.355-359
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• 1996

Rupture of the main bronchus due to blunt chest trauma is very rare, especially In childhood although the incidence is increasing. Early diagnosis and primary repair not. only restore normal lung function but also avoid the difficulties and complications associated with delayed diagnosis and repair. We experienced 2 cases of right main bronchial rupture caused by traffic accidents. Patients suffered from progressively developing dyspnea and subcutaneous emphysema on the neck, anteriorchest,andanteriorabdominalwall. Emergency operations were performed through right posterolateral thoracotomy incision at the 4th intercostal space. Intraoperatively, the right main bronchus completely transsected and separated. Corrective bronchoplasty was performed with end-to-end anastomosis using interrupted suture with 3-0 Vicryle and the suture line was reinforced with azygos vein and parietal pleural flap. Postoperative courses were uneventful and patients discharged without any specific pro lems.

• Sleep Medicine and Psychophysiology
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• v.10 no.1
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• pp.12-19
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• 2003

Sleepiness, or hypersomnia, is a relatively common complaint and one of the main problems of modern society. Accurate evaluation and diagnosis of sleepiness are important. The methods used for evaluating sleepiness are subjective measures or self-evaluations, performance decrease measures, sleep propensity measures, and arousal decrease measures. A clear and detailed history is important in differential diagnosis of sleepiness because symptoms of sleepiness may be expressed in terms of 'tiredness' or 'fatigue' that do not directly denote sleepiness. Comprehensive diagnostic evaluation is also invaluable because these symptoms may result from a variety of causes ranging from medical disorders to insufficient nocturnal sleep.

• Vacuum Magazine
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• v.2 no.1
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• pp.31-34
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• 2015

This article introduces fundamentals of self-diagnosis and predictive (or preventive) maintenance technologies for dry vacuum pumps. The state variables of dry pumps are addressed, such as the pump and motor body temperatures, consumption currents of main and booster pumps, mechanical vibration, and exhaust pressure, etc. The adaptive parametric models of the state variables of the dry pump are exploited to provide dramatic reduction of data size and computation time for self-diagnosis. Two indicators, the Hotelling's $T^2$ and the sum of squares residuals (Q), are illustrated to be quite effective and successful in diagnosing dry pumps used in the semiconductor processes.

• The Journal of the Society of Korean Medicine Diagnostics
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• v.12 no.2
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• pp.18-26
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• 2008

Purpose : To review studies about voice diagnosis in orieltal medicine Method : The papers reviewed in this study were searched through internet search engines. For chinese studies, China National Knowledge Infrastructure(www.cnki.net) was the main source of the information and the key words for Voice diagnosis studies were "(語聲)", "(聲診)", and (TCM). Conclusions : In Oriental Medicine, There are two ways to research about voices. One way is to research through philological consideration with subjectical and experimental diagnosis & studies as human bowel related in traditional studies. The other way is to research through Computerized Speech Lab(CSL), differential diagnosis for Sasang constitution and disease.

• Nuclear Engineering and Technology
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• v.50 no.4
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• pp.582-588
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• 2018

Accident diagnosis is one of the complex tasks for nuclear power plant (NPP) operators. In abnormal or emergency situations, the diagnostic activity of the NPP states is burdensome though necessary. Numerous computer-based methods and operator support systems have been suggested to address this problem. Among them, the recurrent neural network (RNN) has performed well at analyzing time series data. This study proposes an algorithm for accident diagnosis using long short-term memory (LSTM), which is a kind of RNN, which improves the limitation for time reflection. The algorithm consists of preprocessing, the LSTM network, and postprocessing. In the LSTM-based algorithm, preprocessed input variables are calculated to output the accident diagnosis results. The outputs are also postprocessed using softmax to determine the ranking of accident diagnosis results with probabilities. This algorithm was trained using a compact nuclear simulator for several accidents: a loss of coolant accident, a steam generator tube rupture, and a main steam line break. The trained algorithm was also tested to demonstrate the feasibility of diagnosing NPP accidents.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1994.10a
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• pp.670-675
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• 1994

Yhis paper describes a fault diagnosis simulation of the Real-Time Multiple Fault Dignosis System (RTMFDS) for forcasting faults in a system and deciding current machine state from signal information. Comparing with other diagnosis system for single fault,the system developed deals with multiple fault diagnosis,comprising two main parts. One is a remotesignal generating and transimission terminal and the other is a host system for fault diagnosis. Signal generator generate the random fault signal and the image information, and send this information to host. Host consists of various modules and agents such as Signal Processing Module(SPM) for sinal preprocessing, Performence Monotoring Module(PMM) for subsystem performance monitoring, Trigger Module(TM) for multi-triggering subsystem fault diagnosis, Subsystem Fault Diagnosis Agent(SFDA) for receiving trigger signal, formulating subsystem fault D\ulcornerB and initiating diagnosis, Fault Diagnosis Module(FDM) for simulating component fault with Hierarchical Artificial Neural Network (HANN), numerical models and Hofield network,Result Agent(RA) for receiving simulation result and sending to Treatment solver and Graphic Agent(GA). Each agent represents a separate process in UNIX operating system, information exchange and cooperation between agents was doen by IPC(Inter Process Communication : message queue, semaphore, signal, pipe). Numerical models are used to deseribe structure, function and behavior of total system, subsystems and their components. Hierarchical data structure for diagnosing the fault system is implemented by HANN. Signal generation and transmittion was performed on PC. As a host, SUN workstation with X-Windows(Motif)is used for graphic representation.

• The Journal of the Society of Korean Medicine Diagnostics
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• v.22 no.1
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• pp.45-56
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• 2018

The authors are using Qi-diagnosis (integrated diagnosis by bio-energy) that is a method of diagnosis and treatment. We applied Qi-diagnosis to the main study to lay the foundation and framework for research and education about the Korean Medicine. The authors try to describe systemically and specifically the Qi-diagnosis that the authors are using in clinical diagnosis ane treatment so that anyone can use it. The authors have been able to grasp the flow of human bio-energy through years of training. It has had many effects by applying the Qi-diagnosis to patients. The steps of the bio-energy flow have become objective. And the authors have been applied to acupuncture, herbal medicine, moxibustion, bruising treatment and anthrax anesthesia in clinical through the Qi-diagnosis. Also, it is applied to the life management of patients. It is applied to arts such as music therapy and art therapy. The deeper the depth of the Qi-diagnosis, the greater the opportunity to utilize the Qi-diagnosis. The Qi-diagnosis is the origin of the korean medicine. It was able to make diagnosis and treatment correct and to establish clues that the medical problems would be solved through the Qi-diagnosis. In order to do so, the diagnostician must be able to feel the auricular flow of the body accurately and objectively. In addition, he must have a comprehensive understanding of the overall framework of medicine. As a result, diagnosis and treatment of the patient as well as general problems of the patient can be identified and advised, so comprehensive treatment is possible. And it is not only a specific person can do it, but it is a diagnostic method that anyone can take if they take the basic steps step by step.