• Journal of Power System Engineering
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• v.13 no.1
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• pp.53-58
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• 2009

The emergency diesel generator(EDG) of the nuclear power plant is designed to supply the power to the nuclear reactor on Station Black Out(SBO) condition. The operation reliability of onsite emergency diesel generator should be ensured by a conditioning monitoring system designed to monitor and analysis the condition of diesel generator. For this purpose, we have developing the technologies of condition monitoring for the wolsong unit 3&4 standby diesel generator including diesel engine performance. In this paper, technologies of condition monitoring for the wolsong standby diesel generator are described about three step. First is for selection of operating parameter for monitoring. Second is for technologies of online condition monitoring, Third is for monitoring of engine performance.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2000.06a
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• pp.525-530
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• 2000

The vibration shape of the structure with arbitrary boundary condition under excitation is determined by the governing equation and the boundary condition and driving force. In this paper, driving point impedance that is defined by the ratio of the driving force at one point to the velocity of that point is selected as a measure to identify the boundary condition. First, this paper deals with a string with arbitrary boundary condition. It is selected because of its simplicity, but generality of which exhibits the desired physical phenomena. Particularly the relation among the driving point impedance, the boundary condition and the vibration shape is dealt as a primary step to identify the boundary condition by using the driving point impedance.

• Journal of applied mathematics & informatics
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• v.22 no.1_2
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• pp.95-112
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• 2006

In this paper, the authors investigate the condition number with their condition numbers for weighted Moore-Penrose inverse and weighted least squares solution of min /Ax - b/M, where A is a rank-deficient complex matrix in $C^{m{\times}n} $ and b a vector of length m in $C^m$, x a vector of length n in $C^n$. For the normwise condition number, the sensitivity of the relative condition number itself is studied, the componentwise perturbation is also investigated.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2001.11a
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• pp.252-259
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• 2001

Integrated condition monitoring is required to monitor effectively the machine conditions since machine failures could not be monitored accurately by any single measurement parameter. Application of various condition monitoring techniques is therefore preferred in many cases in order to diagnosis the machine condition. However it inevitably requires lots of maintenance cost and sometimes it could be proved to over-maintenance unnecessarily. This could happen especially when one measurement parameter closely correlates to another. Therefore correlation analysis of various monitoring parameters has to be performed to improve the reliability of diagnosis. In this work, Pearson correlation coefficient was used to analyze the correlation between condition monitoring parameters of an over-loaded machine system where the vibration, wear and temperature were monitored simultaneously. The result showed that Pearson correlation coefficient could be regarded as a good measure for evaluating the availability of condition monitoring technology.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.13 no.1
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• pp.45-51
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• 2002

The purpose of this study is to examine the effects of vowel type on the nasalance score. Twenty one male adults without VPI produced 5 types of vowels (/a/, /e/, /i/, /o/, /u/) in two conditions-normal and simulated VPI condition. Nasalance scores were measured for each vowel. These data were compared between conditions and among vowel types. The results were as follow : For all vowels, nasalance scores were significantly higher in simulated VPI condition than in normal condition. The two conditions yielded different patterns in terms of the degree of nasalance across the 5 vowels. In normal condition, nasalance scores were higher in front vowels than in medial or back vowels. But in simulated VPI condition, nasalance scores were higher in high vowels than in mid or low vowels.

• Smart Structures and Systems
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• v.15 no.3
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• pp.751-767
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• 2015

A new procedure is proposed for assessing probabilistic condition of structures considering effect of measured data uncertainty. In this procedure, multiple Finite Element (FE) models are identified by using weighting vectors that represent the uncertainty conditions of measured data. The distribution of structural parameters is analysed using a Principal Component Analysis (PCA) in relation to uncertainty conditions, and the identified models are classified into groups according to their similarity by using a K-means method. The condition of a structure is then assessed probabilistically using FE models in the classified groups, each of which represents specific uncertainty condition of measured data. Yeondae bridge, a steel-box girder expressway bridge in Korea, is used as an illustrative example. Probabilistic condition of the bridge is evaluated by the distribution of load rating factors obtained using multiple FE models. The numerical example shows that the proposed method can quantify uncertainty of measured data and subsequently evaluate efficiently the probabilistic condition of bridges.

• The Mathematical Education
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• v.48 no.3
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• pp.287-302
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• 2009

This study investigated how 5th grade students found and understood triangle congruence conditions (SSS, SAS, ASA). In particular, this study focused on children's processes of discovering triangle congruence conditions and the obstacles which they encountered in the process of making sense of these conditions. Our data indicates that inquiring the cases in which less than three factors of triangle are given is helpful for children to guess triangle congruence conditions and understand the minimal characteristic of these conditions. And the degree of difficulty of discovering each congruence condition is different. Children discovered SAS condition and ASA condition easily, but it was hard for them to discover and understand that SSS was also a triangle congruence condition because they connected the length of a given side with the use of a scaled ruler not a compass.

• International Journal of Reliability and Applications
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• v.2 no.1
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• pp.57-71
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• 2001

Global competition to increase production output and to improve quality is spurring manufacturing companies to use condition monitoring and fault diagnostic systems for predictive maintenance. As monitoring, testing, and measuring techniques develop, predictive control of components and complete systems have become more practical and affordable. In this article, we will consider the computer based data acquisition system for condition monitoring and the condition parameter analysis techniques for fault detection and diagnostics in the machinery and briefly discuss reliability prediction and the limit value determination in condition monitoring.

• International Journal of Internet, Broadcasting and Communication
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• v.15 no.3
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• pp.203-210
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• 2023

In this paper, we develope a stock trading system that automatically buy and sell stocks in Kiwoom Securities' HTS system. The system is made by using Kiwoom Open API+ with the Python programming language. A trading strategy is based on an enhanced system query method called a Condition-Search. The Condition-Search script is edited in Kiwoom Hero 4 HTS and the script is stored in the Kiwoom server. The Condition-Search script has the advantage of being easy to change the trading strategy because it can be modified and changed as needed. In the HTS system, up to ten Condition-Search scripts are supported, so it is possible to apply various trading methods. But there are some restrictions on transactions and Condition-Search in Kiwoom Open API+. To avoid one problem that has transaction number and frequency are restricted, a method of adjusting the time interval between transactions is applied and the other problem that do not support a threading technique is solved by an IPC(Inter-Process Communication) with multiple login IDs.

• Journal of Technologic Dentistry
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• v.29 no.1
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• pp.103-119
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• 2007

The survey on dental health condition and eating habit of local residents in Daegu and Kyungbuk had been conducted. Through the analysis of influence of dental health condition on eating habit I could get the following result. The number of subjects of survey is 630. The period of survey is from June 2006 to September 2006. 1. General quality of subjects is that forty-four point four percent of subjects are male and fiftyfive pointsix percent are female. The age of thirty point one percent of subjects is between 20 and 29. Fifty-six point two percent of subjects are married. Fifty-one point four percent of subjects have above bachelor degree. Monthly income of forty-four point eight percent of subjects is less than one million won. Twenty-four point four percent of subjects are students. Fifty-five point seven percent of subjects are living in big cities. 2. Forty-seven point seven percent of male and fifty-one point eight percent of female answered their subjective dental health condition is bad. Marital status, age and academic background have relationship with answer. Forty-three point nine percent of married subjects and forty-one point five percent of divorced or bereaved subjects said they have bad dental health condition. The older he is or the lower academic background he has subjects think they have bad dental health condition. Forty-seven point four percent of non-educated subjects answered their dental health condition is bad. Forty-six percent of self-employed subjects and subjects who live in the country have tendency to think their dental health condition is bad. 3. About eating habit knowledge, male's knowledge of 2.03$\pm$0.20 is lower than female's of 2.08$\pm$0.21. This shows there is statistically significant difference(p<0.01). 4. There is significant relationship between subjective dental health condition and health condition of subjective. This means subject who has better health condition has also better dental health condition(37.5%). About subjective dental health condition, subject who eats restoratives has worse dental health condition. This shows there is a relationship between dental health condition and eating restoratives(p=0.004) and subject who works out steadily has better dental condition. 5. About relation between dental health condition and eating habit, subject who eats vegetables has worse dental health condition by fifty point seven percent. As cross tabulation result, p-value is 0.002. In level of significance of 0.05, there is statistically significant difference in eating habit. 6. It seems that eating habit has an effect on marital status, age, academic background, income and also on dental prosthetic treatment situation. Many subjects think their dental health condition is bad. About eating habit, subjects who eat meat have better dental health condition. Subjects who drink green tea and fruit juice has better dental health condition than who drink coffee and Balanced diet is good for dental health condition. As eating habit is important for developing dental health, government should make a proper program. Dental health education program especially for elderly, low-eduacted, residents in the country and poor people should be developed. Government, dental health organization, dental health specialist, associated research institution and people work in the press should be concerned and devote to improve quality of life. Primary prevention education will help for dental health.