• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1992년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 19-21 Oct. 1992
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• pp.123-128
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• 1992

This paper presents an autotuning algorithm of scaling factor in order to improve system performance. We define the scaling factor of fuzzy controller as a function of error and error change. This function is tuned by the output of performance evaluation level utilizing the error of overshoot and rising time. Simulation results show that the proposed algorithm has good tuning performance for a system with parameter change.

• 한국콘텐츠학회논문지
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• 제14권8호
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• pp.453-465
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• 2014

이 연구는 중학생을 대상으로 계획된 방과후체육활동 참여 여부에 따라 심리적 안녕감에 어떠한 변화차이가 있는지를 알아보는 것에 목적이 있었다. 이러한 연구목적을 달하기 위하여 K시 M중학교 남학생 중 방과 후 활동에 참여하는 학생 100명을 선정하였다. 측정도구는 박정희(2007)가 개발한 청소년 심리적 안녕감 측정도구를 타당도 검증절차를 거친 후에 사용하였다. 실험집단은 1주에 2차시씩 총 12주 동안 계획된 방과후체육활동에 참여하였고, 통제집단은 일반 교과과목 수업에 참여하였다. 실험설계는 사전 사후로 나누어 두 차례 반복측정에 의한 이원변량분석을 실시하였다. 이 연구에서 도달한 연구결과를 토대로 결론을 제시하면 다음과 같다. 첫째, 계획된 방과후체육활동에 참여한 집단과 교과활동에 참여한 집단은 가족관계 요인의 변화에서 통계적으로 의미 있는 차이가 있다. 둘째, 두 집단은 교사관계 요인의 변화에서 통계적으로 의미 있는 차이는 없다. 셋째, 두 집단은 자기인식 요인의 변화에서 통계적으로 의미 있는 차이가 있다. 넷째, 두 집단은 자기 주장성 요인의 변화에서 통계적으로 의미 있는 차이는 없다. 다섯째, 두 집단은 심리적 안녕감 중 친구관계 요인의 변화에서 통계적으로 의미 있는 차이가 있다. 여섯째, 두 집단은 심리적 안녕감 중 학습 주도성 요인의 변화에서 통계적으로 의미 있는 차이는 없다. 종합해 볼 때, 중학생 시기에 계획된 방과후체육활동은 가족이나 부모에 대한 관심과 사랑에 대한 느낌을 확장시킬 수 있고, 자신에 대하여 긍정적인 인식과 삶에 대한 태도를 가질 수 있으며, 친구들과 친밀한 관계를 가짐으로써 상호신뢰를 쌓아갈 수 있도록 도움을 줄 수 있다.

• 한국기계가공학회지
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• 제19권6호
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• pp.49-54
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• 2020

The purpose of this study is to investigate the effects of the change in the spindle speed and the feed rate on the diameter change of a hole using a boring cutter for the internal boring process of AL6061-T4 alloys. The experimental results are quantitatively analyzed by applying the factor analysis and the response surface analysis of the experimental design method. The tendency of the diameter change according to the change in the spindle speed and feed level is also evaluated. During the internal boring process of AL6061-T4 alloys, the main factor affecting the diameter change is the spindle speed in which the diameter decreases as the number of revolutions increases. In addition, the diameter tends to increase as the feed is increased; however, as the number of spindle revolutions increases, the influence of the feed decreases.

• 한국산업융합학회 논문집
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• 제6권4호
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• pp.367-371
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• 2003

In order to determine the effective way of measuring the Mode I stress intensity factor for a material containing a two-dimensional surface crack by means of the alternating current potential drop(ACPD) technique, the change in magnetic flux density between crack surfaces and above the specimen surface due to load was studied theoretically. The magnetic flux density in the air between crack surfaces is uniform and above the specimen surface is not changed by increasing the load in the material. Therefore, the change in potential drop due to load in a measuring system which was designed to induce a large amount of electro-motive force was caused by the change in internal inductance of material, the change in the mutual inductance between internal inductance of material and measuring system and the change in the mutual inductance between internal inductance of material and power supply line.

• 대한조선학회지
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• 제4권1호
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• pp.55-58
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• 1967

It is investigated that in what shape the stress concentration factor of a notched strip under pure bending changes due to unsymmetrically varying notch angle. Four models made of CR-39, having parameters of r/d-0.225, h/r=4; r/d=0.225, h/r=2; r/d=0.4, h/r=4 and r/d=0.4, h/r=2 respectively as shown in Fig.1, Fig.2 and Table are tested with the use of polariscope. For each model, notch angle is unsymmetrically varied from $0^{\circ}$ to $180^{\circ}$ at intervals of $15^{\circ}$ as shown in Fig. 1 and Fig. 2. The results of this experiment are Fig. 7 and Fig. 8 and the following are deduced. As notch angle increases 1) from $0^{\circ}$ to $50^{\circ}$, the decrement of concentration factor is slight. 2) from $50^{\circ}$ to 90, the decrement of concentration factor is a little steeper. 3) from $30^{\circ}$ to $140^{\circ}$, the decrement of concentration factor is slight. 4) from $140^{\circ}$ to $180^{\circ}$, the decrement is very steep with an abrupt with an abrupt change in the neighborhood of $140^{\circ}$.

• 대한가정학회지
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• 제31권4호
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• pp.115-132
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• 1993

This study was designed with the purpose to analyze the factor structure of family life events and to clear the influence of related variables on family life events. The frequence of experienced events and the degree of importance of events which were the constituent components of family life events was estimated by the 650 married woman in Kangju. The results were as follows: 1. 15 factors of family life events derived by factor analysis: F.1「Expenditure and economic loss」, F.2「Growth and change of children」, F.3「Change of family structure」, F.4「Family's change」, F.5「Change of life level」, F.6「Family's social problem」, F.7「Need of care」, F.8「Family's health」, F.9「Marital relationship」, F.10「Family's social damage」, F.11「Breach with acquaintance」, F.12「Financial difficulties」F.13「Husband's problem」, F.14「Housewives' social activity」, F.15「Kinship's support」. 2. There frequence of experienced family life events such as expenditure and economic loss and breach with acquaintance was highest. 3. The degree of importance about experienced family life events such as growth and change of children was highest. 4. Age, family life cycle have significantly differenced on the degree of importance and the frequence of experienced events. 5. Education's level, family size, income, housewives' employment and family structure have differently differenced on the degree of importance and the frequence of experienced events according event factor.

• 한국기후변화학회지
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• 제9권1호
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• pp.81-90
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• 2018

"The Framework Act on Low-Carbon Green Growth" specifies the requirements for the development and verification of emission factors for establishing reliable national greenhouse gas statistics. The scope of the regulations covers the development and validation of energy, industrial processes, solvents and other product use, agriculture, land use, land use change and emission and absorption coefficients of the forestry and waste sector as defined in the 1996 IPCC Guideline and GPG 2000, The minerals sector to be covered in this study belongs to industrial processes. As a representative method for quantifying and evaluating GHG emission factors, there are emission grade quality grading and DARS (Data Rating Rating System) in the 'Procedures for Preparing Emission Factor Documents (1997)' reported by US-EPA. However, the above two methods are not specific and comprehensive, and lack the details for accurate emission factor verification. Therefore, there is a need for a method for verifying and quantifying certified greenhouse gas emission factors that reflects characteristics of each industry sector in Korea and accord with IPCC G/L and GHG target management. In this study, we conducted a weighted study on quantitative and evaluation lists of emission factor using questionnaires to develop a more accurate methodology for quantifying national greenhouse gas emission factors in the mineral sector. Quantification and evaluation of emission factor are classified into essential verification and quality evaluation. The essential verifications are : administrative compatibility, method of determining emission factors, emission characteristics, sampling methods and analysis methods, representativeness of data. The quality evaluations consisted of the quality control of the data, the accuracy of the measurement and analysis, the level of uncertainty, not directly affect the emission factor, but consisted of factors that determine data quality.

• 대기
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• 제25권2호
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• pp.249-260
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• 2015

The changes in thermodynamic and dynamic aspects on near (2025~2049) and long-term (2075~2099) future climate changes between the historical run (1979~2005) and the Representative Concentration Pathway (RCP) 4.5 run with 20 coupled models which employed in the phase five of Coupled Model Inter-comparison Project (CMIP5) over East Asia (EA) and the Korean Peninsula are investigated as an extended study for Moon et al. (2014) study noted that the 20 models' multi-model ensemble (MME) and best five models' multi-model ensemble (B5MME) have a different increasing trend of precipitation during the boreal winter and summer, in spite of a similar increasing trend of surface air temperature, especially over the Korean Peninsula. Comparing the MME and B5MME, the dynamic factor (the convergence of mean moisture by anomalous wind) and the thermodynamic factor (the convergence of anomalous moisture by mean wind) in terms of moisture flux convergence are analyzed. As a result, the dynamic factor causes the lower increasing trend of precipitation in B5MME than the MME during the boreal winter and summer over EA. However, over the Korean Peninsula, the dynamic factor causes the lower increasing trend of precipitation in B5MME than the MME during the boreal winter, whereas the thermodynamic factor causes the higher increasing trend of precipitation in B5MME than the MME during the boreal summer. Therefore, it can be noted that the difference between MME and B5MME on the change in precipitation is affected by dynamic (thermodynamic) factor during the boreal winter (summer) over the Korean Peninsula.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2006년도 춘계학술대회 논문집
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• pp.120-124
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• 2006

In this study, psychological assessment was carried out to investigate the driver's psychological characteristics by the change of the headlight. The participants were 20 men and 20 women in their 20s and thirty-two different conditions in combinations of waveform of light, voltage, and alteration time were used. The questionnaire for the assessment was evaluated by 8 subjective items and 5-point SD criteria of 19 pair's adjective. The results were as follows. 1. The assessment results from SD method indicated 3 factors by factor analysis, and it was shown that A waveform had significances in a sense of security and impetus and B waveform had a significance in a sense of security The levels of the limitations for the voltage change were 12V in the factor of a sense of security and 11V in the factor of a sense of impetus for A waveform, 12.6V in the factor of a sense of security for B waveform. 2. The results of the subjective assessment showed that the limitation of A waveform's brightness change was 12V. Moreover, the limitations of voltage changes were 12.6V for B waveform brightness change, 12V for discomfort, 12.6V for darkness. And the limitation of C waveform's brightness change was 12V.

• 소성∙가공
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• 제1권1호
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• pp.42-51
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• 1992

The ring compression test has been widely employed as an experimental means to determine the friction factor. The calibration curves are obtained by the rigid-plastic finite element analysis for various work-hardening exponent and strain-rate hardening exponent. The effects of work-hardening exponent and strain-rate hardening exponent are thoroughly studied and discussed from the finite element computation. The change of friction factor during height reduction in ring compression is also discussed. Then, the method to estimate the change of friction factor during ring compression is proposed.