• Nuclear Engineering and Technology
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• v.36 no.3
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• pp.219-228
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• 2004

[1] and [2] present an approach to diagnosing possible defects in the mechanical systems of a nuclear power plant. In this paper, by using a fault library as a database and training data, we develop a diagnostic algorithm 1) to decide whether an Air Operated Valve system is sound or not and 2) to identify the defect from which an Air-Operated Valve system suffers, if any. This algorithm is composed of three stages: a neural net stage, a non-neural net stage, and an integration stage. The neural net stage is a simple perceptron, a pattern-recognition module, using a neural net. The non-neural net stage is a simple pattern-matching algorithm, which translates the degree of matching into a corresponding number. The integration stage collects each output and makes a decision. We present a simulation result and confirm that the developed algorithm works accurately, if the input matches one in the database.

• KIEE International Transaction on Systems and Control
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• v.2D no.2
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• pp.120-124
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• 2002

A new methodology is presented to diagnose faults in equipment plasma. This is accomplished by using neural networks as a pattern recognizer of radio frequency (rf) impedance match data. Using a match monitor system, the match data were collected. The monitor system consisted mainly of a multifunction board and a signal flow diagram coded by Visual Designer. Plasma anomaly was effectively represented by electrical match positions. Twenty sets of fault-symptom patterns were experimentally simulated with variations in process factors, which include rf source power, pressure, Ar, and $O_$2 flow rates. As an input to neural networks, two means and standard deviations of positions were used as well as a reflected power. Diagnostic accuracy was measured as a function of training factors, which include the number of hidden neurons, the magnitude of initial weights, and two gradients of neuron activation functions. The accuracy was the most sensitive to the number of hidden neurons. Interaction effects on the accuracy were also examined by performing a 2$^$4 full factorial experiment. The experiments were performed on multipole inductively coupled plasma equipment.

• Computers and Concrete
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• v.2 no.6
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• pp.439-454
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• 2005

When deterioration of concrete is observed in a structure, it is highly desirable to determine the cause of such deterioration. Only by understanding the cause can an appropriate repair strategy be implemented to address both the cause and the symptom. In colder climates, bridge deck deterioration is often caused by chlorides from de-icing salts, which penetrate the concrete and depassivate the embedded reinforcement, causing corrosion. Bridge decks can also suffer from other deterioration mechanisms, such as alkali-silica reaction, freeze-thaw, and shrinkage. There is a need for a comprehensive and integrative system to help with the inspection and evaluation of concrete bridge deck deterioration before decisions are made on the best way to repair it. The purpose of this research was to develop a model to help with the diagnosis of concrete bridge deck deterioration that integrates the symptoms observed during an inspection, various deterioration mechanisms, and the probability of their occurrence given the available data. The model displays the diagnosis result as the probability that one of four deterioration mechanisms, namely shrinkage, corrosion of reinforcement, freeze-thaw and alkali-silica reaction, is at fault. Sensitivity analysis was performed to determine which probabilities in the model require refinement. Two case studies are included in this investigation.

• Child Health Nursing Research
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• v.4 no.2
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• pp.193-206
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• 1998

The purpose of this study was to examine the stressors and stress coping styles of 6th grade el ementary school children and to explore the relationship between stressful life events and health symptoms and the effects of coping style which is theoretically considered to mediate the relationship between stress and health symptoms. The study subjects consisted of 329 in 6th grade elementary school children in Cheong-Ju city. Of the 329 subjects, 171 were boys and 158 were girls. For this study, three kinds of questionnaires were adopted as follows ; 1) Feel Bad Scale (FBS) by Lewis et al., 2) lazarus-Folkman's Way of coping questionnaire 3) Hee Sun Shin's Health Symptom questionnaire (HSQ) The researcher visited the school and collected data in the class using the questionnaire method after an explanation of the purpose and procedures was given to the children. Data collection was done for 10 days (from 5th to 15th of July 1997) . The data were analyzed by descriptive statistics, correlation analysis, multiple regression analysis using the SAS statistical program. The results of this study were as follows : 1. The mean score for the FBS was 211.37(range : 77-427), The most severe stressors perceived by children were parental divorce and other's smash or steal of my things. The most frequently experienced stressful life events were conflict with siblings and being scolded for other's fault. 2. The most frequently used stress coping style was the active coping (M=17.85), followed by passive (M=13.64) and magical one (M=13.42). 3. The mean score for the HSQ was 23.30(range : 0-72) The most frequently complained health symptoms were headache and having much worry about everything. 4. There was a significant relationship between stressful life events and health symptoms (r=.60, p<.001). Also, stressful life events were positively related with passive coping(r=.27, p<.001) and magical coping (r=.38, p<.001). Health symptoms were positively correlated with passive coping(r=.33, p<.001) and magical coping (r=.41, p<.001). 5. Stepwise multiple regression analysis revealed that the most powerful predictor was the variable of stressful life events. Health concerns, magical coping style, passive coping style and active coping style accounted for 49.15% of the variance in health symptoms. This study revealed that stressful life events correlated with health symptoms in 6th grade elementary school children and passive coping and magical coping had mediating effects on this relationship. The implication for nursing is that there is a need to develop supportive interventions for high risk population to decrease health problems due to stress.

• The Korean Society of Law and Medicine
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• v.22 no.2
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• pp.49-79
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• 2021

Due to defendant's wrongful act by implant surgery, plaintiff has been suffered serious damages to his face and teeth, and pain caused by establishing implanted teeth. Jeonju Appellate Court sentenced to pay future medical expenses and alimony to the plaintiff in compensation for breach of duty or torts. The ruling is designed to relieve the burden of proof because it is extremely difficult for non-experts to determine whether dentists violated their 'duty of care' or whether there was a causal relationship between damages to medial treatment. It was judged that if symptoms that contributed to the patient's significant outcome occurred during or after surgery, such symptoms could be presumed to have been caused by medical negligence if indirect facts were proven to be other than medical negligence. Originally, the shifting of burden of proof in Germany, has already been developed in medical malpractice case since 1940s. In order to guarantee the patients' right, §630h German Civil Code (BGB) - presumption of negligence in the realization of controllable risk- has been also legislated. BGH (Bundesgerichtshof) has been interested in ensuring that the principle of equality between patients and doctors. So, in this study, we wanted to refer to German precedent cases to analyzing Korean medical malpractice lawsuit. In particular, the decision could be significant in that it approaches closer to allows the shifting burden of proof in drastically growing dental malpractice cases. This is clearly confirmed in the judgment of the dentist's "fault" that "if indirect facts about the symptom or occurrence are proven to be cause other than medical negligence, such symptoms can be presumed to be due to medical negligence."