• International Journal of Reliability and Applications
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• 제12권1호
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• pp.49-60
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• 2011

The geometric process (GP) has been widely used for modeling failure and repair time sequences of repairable systems. The GP is mathematically tractable but restrictive in reliability applications since it actually assumes that the mean function of inter-failure times sequence asymptotically decreases to zero; and the mean function of successive repair times sequence asymptotically increases to infinity. This is generally unrealistic from an engineering perspective. This paper presents three extended GP models for modeling reliability deterioration and improvement (or growth) process. The extensions maintain the advantage of mathematical tractability of GP model. Their usefulness and appropriateness are illustrated with three real-world examples.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2010년도 춘계학술대회 논문집
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• pp.1492-1499
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• 2010

This paper is intended as an development of moving load simulation techniques. The concern with dynamic problem of railway bridge caused by the moving train loads has been growing. Over the past few years, several studies have been made on dynamic stability of railway bridge analytically. But very few attempts have been made at experimental research. From the dynamic stability view point, the moving train loads simulation test is revolutionary idea. It can be replace restrictive filed test with new laboratory test. This study investigates minimum specifications of hardware and basic parameters. it is used 39m girder and 4 actuators for experimental verification.

• 센서학회지
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• 제13권2호
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• pp.133-138
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• 2004

Today, the obstacle detection system has massive size and restrictive detection range. To solve these problems, this paper proposes the capacitance variation detector using the variated capacitance value as a result of the obstacle approaching. If obstacle approaches, the capacitance value of capacitance sensor is increased and the operating frequency of oscillator is decreased. Then this changed frequency appears to the output of the mixer that operate down conversion. The capacitance variation detector is produced by Hynix$0.35{\mu}$ CMOS process. In experiment result, the frequency of final output is 6.81 MHz at no obstacle and 31.45 MHz at approaching obstacle. In conclusion, proposed capacitance variation detector has small size, low power consumption and easiness to set up anywhere. So it is expected to substitute the obstacle detector.

• 한국정밀공학회지
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• 제27권3호
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• pp.27-32
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• 2010

The OMM(On-Machine-Measurement) system has many advantages compare to conventional measurement in the way the time and cost. But, the sensor suitable to OMM system is restrictive use. Touch trigger probe sensor has long time for measurement and non-contact sensor has directional demerit. Because the long mechanical parts such as gear and lead screw for pump, injector and machine tools has big and heavy, unclamp and transferring for measurement in machining process is very difficult. This paper presents a development of ultra miniature eddy current displacement sensor with 3 axes for On-Machine-Measurement system. The accuracy of the sensor is experimentally proved in the grinding machine. In experimental results, the accuracy has under ${\pm}5\;{\mu}m$.

• Journal of Chest Surgery
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• 제33권3호
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• pp.252-256
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• 2000

There have been few reports documenting the outcome of arterial swich operations(ASO) in selected patients with transposition of great arteries(TGA) and with left ventricular outflow tract obstruction(LVOTO). In the case of TGA with LVOTO, if the atrial septal defect(ASD) is large and the ventricular septal defect(VSD) is restricive, this deprives the left ventricle(LV) of approporiate preload and could lead to underdevelopment of the ventircular mass and lead poor LV performance after the arterial switch operation, dspite a high pressure in the LV preoperatively. Because an increase in the systolic ventricular pressure is not necessarily paralleled by an increase in ventricular mass, which is also essential for optimal ventricular performance after the operation. We report here a case of rapid LV training after ASO in TGA with unprepared LV (because of large ASD and restrictive VSD) despite a high pressure in the LV(due to LVOTO) preoperatively.

• 아동학회지
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• 제24권6호
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• pp.61-79
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• 2003

For this study of adolescent attitudes toward child sexual abuse, 200 students attending high school and college participated in a group survey. The Child Sexual Abuse Myth Scale (Collings, 1999) was used to measure social attitudes toward child sexual abuse. Overall, the attitudes of the respondents placed between negative and positive attitudes. Nevertheless, strong negative myths and stereotypes, particularly blame diffusion, denial of abusiveness, and restrictive abuse stereotypes were found in specific situations. High school students and male students had more negative myths and stereotypes than college students and female students. Hierarchical regression analysis indicated the variables of education level and gender as the most important predictors in explaining students' attitudes toward child sexual abuse.

• 아동학회지
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• 제28권5호
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• pp.269-284
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• 2007

A sample of 654 elementary school children(330 boys and 324 girls) and their mothers responded to three questionnaires regarding mother's job satisfaction and parenting behavior and children's problem behavior. Results showed that working mothers perceived themselves as more permissive/neglecting compared with non-working mothers. Children of working mothers perceived themselves as hyperactive, anxious, withdrawn, aggressive, and immature. Parenting of working mothers with higher job satisfaction was more warm/accepting; their daughters perceived themselves as less anxious, withdrawn, and immature than children of mothers with lower job satisfaction. Children of rejecting/restrictive working mothers, especially girls, reported hyperactive, withdrawn, aggressive, and immature behaviors. Children of permissive/neglecting working mothers were immature. Warm/accepting parenting of working mothers played mediating roles between their job satisfaction and maturity of their daughters' behavior.

• 한국주거학회:학술대회논문집
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• 한국주거학회 2004년도 추계학술대회 논문집
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• pp.207-212
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• 2004

The propose of this study is to grasp actual status and needs of leisure of middle age. The questionnaire survey is used, the subjects are middle age from 40${\sim}$50's living in big city. The questionnaire consists of leisure, leisure actual condition, leisure satisfaction and need. Frequency, percent, average, x2-test, t-test and ANOVA are used for data analysis. The results of this study are as following; First, leisure is necessary to elevate Quality of life in terms of spiritual , psychological stability and physical health. Second, subjects have more leisure time in weekend the characteristics of leisure time are scattered in woman. Third, in the future the subjects wish to have leisure with family. Therefore, it is necessary to develop leisure program and facilities to promote family leisure. Fourth, the subjects are not satisfied with current leisure for unsufficiency of leisure time, cost, facility and program. Fifth, present leisure behavior characteristics are restrictive and passive. In the near future, however, they showed desire to engage in divers forms of leisure including active and participant leisure.

• 대한가정학회지
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• 제39권3호
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• pp.11-23
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• 2001

Parental attitudes and mediation of children's television viewing has focused primarily on broadcast television, although recent developments in technology have greatly expanded the availability of VCRs in home environment. To build a more comprehensive model of parental mediation of TV Viewing in the new video environment, this article analyzed parental attitudes toward children's video viewing and factors associated with parental mediation of children's video viewing using questionnaire responses from 659 mothers of four to six-year-old children. Both restrictive and evaluative parental mediation were associated with not only parental factors but also contextual factors. Descriptive data on parental attitudes and mediation of children's video viewing were also presented.

• 한국콘텐츠학회논문지
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• 제2권4호
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• pp.93-98
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• 2002

함수 방정식은 연구원들이 함수 자체의 정확한 형태를 가정하지 않고 단순히 기본적인 함수의 성질만을 언급하는 한정적이지 않은 방정식을 통하여 일반적인 관점의 수학적 형상화를 공식화하는데 매우 중요한 구실을 하기 때문에 실험적인 학문에서 유용하다. 그러한 많은 함수 방정식 가운데에서 이 논문은 다소 일반화된 2차 함수 방정식을 선택해 해를 구하며 이 방정식의 안정성을 증명한다. a$^2$f((x+y/a))+b$^2$f((x-y/b)) = 2f(x)+2f(y)