• Title/Summary/Keyword: Change Factor

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Fuzzy control with auto-tuning scaling factor (스켈링 계수 자동조정을 통한 퍼지제어)

  • 정명환;정희태;전기준
    • 제어로봇시스템학회:학술대회논문집
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    • 1992.10a
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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.

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Change of Psychological Well-being by Participating in an after School Physical Training Activity (방과후체육활동 참여에 따른 심리적 안녕감 변화)

  • Lim, Tae-Hee;Kim, Dong-Hyun
    • The Journal of the Korea Contents Association
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    • v.14 no.8
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    • pp.453-465
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    • 2014
  • The purpose of this study was to find out the change in psychological well-being of middle school students by participating in after school physical training activities. To achieve this object, 100 male students of M middle school in K city. "Teenagers' psychological well-being measurement tool" developed by Chung-hee Park(2007). Twice a week, for twelve weeks, the experimental group took part in an after school physical training activity, and the control group, in non-physical classes. The conclusion reached based on the result of this study are as follows. First, there was a statistically significant difference in the change of the family relations factor. Second, there was no statistically significant difference in the change of the student-teacher relations factor between the group Third, there was a statistically significant difference in the change of the self-awareness factor between the group. Fourth, there was no statistically significant difference in the change of the self assertiveness factor between the group. Fifth, there was a statistically significant difference in the change of the friendship factor between the group. Sixth, there was no statistically significant difference in the change of the self-initiative studying factor between the group. In conclusion, taking part in an after school physical training activity on a regular basis can increase the feeling of care and love from family relations, give positive self awareness and attitude towards life, and help building mutual trust between friends by having close relationship.

A study on the Change of Diameter Based on Cutting Conditions in AL6061-T4 Boring Machining (AL6061-T4의 보링가공 시 절삭조건에 따른 직경 변화에 관한 연구)

  • Chun, Se-Ho
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.19 no.6
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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.

Theoretical Analysis of Change in Magnetic Flux Density Due to Load for Measuring KI (응력확대계수측정을 위한 하중에 의한 자속밀도변화의 이론적 해석)

  • Lee, Jeong-Hee
    • Journal of the Korean Society of Industry Convergence
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    • v.6 no.4
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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.

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A Photoelastic Study on Change of Stress Concentration Factor Due to Unsymmetrical Change of Notch Angle (Pure Bending Moment 하(下)에 있는 Notched Strip에서의 Notch Angle의 비대칭적(非對稱的) 변화(變化)에 의(依)한 응력집중계수(應力集中係數)의 변화(變化))

  • Jang-Chule,Mun
    • Bulletin of the Society of Naval Architects of Korea
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    • v.4 no.1
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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 $140^{\circ}$.

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The Facotr Structure of Urban Family Life Events and Related Variables (도시 가정의 생활사건 요인구조와 관련변인)

  • 임정빈
    • Journal of the Korean Home Economics Association
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    • v.31 no.4
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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.

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Future Change Using the CMIP5 MME and Best Models: II. The Thermodynamic and Dynamic Analysis on Near and Long-Term Future Climate Change over East Asia (CMIP5 MME와 Best 모델의 비교를 통해 살펴본 미래전망: II. 동아시아 단·장기 미래기후전망에 대한 열역학적 및 역학적 분석)

  • Kim, Byeong-Hee;Moon, Hyejin;Ha, Kyung-Ja
    • Atmosphere
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    • v.25 no.2
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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.

A Study on the Quantitative and Evaluation Weights of National Greenhouse Gas Emission Factors in the Mineral Industry (광물산업의 국가온실가스배출계수 정량·평가항목 가중치에 관한 연구)

  • Yoon, Yoongjoong;Cho, Changsang;Jeon, Eui Chan
    • Journal of Climate Change Research
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    • v.9 no.1
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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.

A Study on Driver's Perception over the Change of the Headlamp's Illuminance : 3. Driver's psychological property (전조등 조도변동에 대한 운전자의 인식연구 : 3. 운전자의 심리적 특성)

  • Kim, Hyun-Ji;Kim, Hyun-Jin;Kim, Gi-Hoon;Kim, Hoon;An, Ok-Hee
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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    • 2006.05a
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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.

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Effects of Work-Hardening Exponent and Strain-Rate Hardening Exponent on the Determination of Friction Factor (가공경화지수 및 변형율속도 경화지수의 변화가 마찰상수 결정에 미치는 영향)

  • Park, C.Y.;Yang, D.Y.
    • Transactions of Materials Processing
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    • v.1 no.1
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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.

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