• 제목/요약/키워드: R-Factor

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기후변화에 따른 R-Factor 값을 고려한 토양 유실량 평가 (The Evaluation of Soil Loss Considering the R-Factor Value Following the Climate Change)

  • 박재현;김동주;김민규;장춘화;강현우;금동혁;임경재
    • 한국관개배수논문집
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    • 제21권1호
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    • pp.64-77
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    • 2014
  • This study evaluated the soil loss considering the R-Factor value following the climate change. To calculate the soil loss of the basin in Jaun-ri, Hongcheon-gun which is the study area, the future climate change scenario and convenience revision were used to build the past 30 years, future 30 years R-Factor and it was applied to USLE model. As a result, as the R-Factor value declined a little in the future, the soil loss was also reduced but it corresponds to the 'very high' according to the OECD soil loss grade so the solution to reduce the soil loss is necessary and it can be used for another study material.

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R2SDF FFT의 메모리 감소를 위한 회전인자 인덱스 생성방법 (Twiddle Factor Index Generate Method for Memory Reduction in R2SDF FFT)

  • 양승원;김용은;이종열
    • 대한전자공학회논문지SD
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    • 제46권5호
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    • pp.32-38
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    • 2009
  • FFT(Fast Fourier Transform) 프로세서는 OFDM(Orthogonal Frequency Division Multiplexing) 시스템에서 사용된다. 근래에는 광대역과 이동성에 대한 요구가 높아짐에 따라 큰 포인트를 가지는 FFT 프로세서의 연구가 필요하다. FFT 포인트 수가 증가할수록 회전인자가 저장된 메모리가 차지하는 면적은 증가한다. 본 논문에서는 Radix-2, $2^2,\;2^3,\;2^4$ 알고리즘의 회전인자 인덱스 생성 방법을 제안한다. 제안한 회전인자 인덱스 생성기(Twiddle Factor Index Generator : TFIG)는 간단하게 카운터와 양수곱셈기로만 구성된다. 각각의 R2SDF(Radix-2 Single-Path Delay Feedback), $R2^2SDF,\;R2^3SDF,\;R2^4SDF$ 1024포인트 FFT 프로세서에 ROM 크기를 1/8N로 줄인 회전인자 계수 생성기(Twiddle Factor Coefficient Generator : TFCG)를 설계하여 제안한 알고리즘을 검증하였다. $R2^4SDF$의 TFCG 경우 면적, 전력에서 각 57.9%, 57.5%정도의 이득을 얻었다.

Investigation of dynamic P-Δ effect on ductility factor

  • Han, Sang Whan;Kwon, Oh-Sung;Lee, Li-Hyung
    • Structural Engineering and Mechanics
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    • 제12권3호
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    • pp.249-266
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    • 2001
  • Current seismic design provisions allow structures to deform into inelastic range during design level earthquakes since the chance to meet such event is quite rare. For this purpose, design base shear is defined in current seismic design provisions as the value of elastic seismic shear force divided by strength reduction factor, R (${\geq}1$). Strength reduction factor generally consists of four different factors, which can account for ductility capacity, overstrength, damping, and redundancy inherent in structures respectively. In this study, R factor is assumed to account for only the ductility rather than overstrength, damping, and redundancy. The R factor considering ductility is called "ductility factor" ($R_{\mu}$). This study proposes ductility factor with correction factor, C, which can account for dynamic P-${\Delta}$ effect. Correction factor, C is established as the functional form since it requires computational efforts and time for calculating this factor. From the statistical study using the results of nonlinear dynamic analysis for 40 earthquake ground motions (EQGM) it is shown that the dependence of C factor on structural period is weak, whereas C factor is strongly dependant on the change of ductility ratio and stability coefficient. To propose the functional form of C factor statistical study is carried out using 79,920 nonlinear dynamic analysis results for different combination of parameters and 40 EQGM.

접합부 회전능력에 기초한 철골모멘트골조의 반응수정계수 산정법 (Rational Evaluation of Seismic Response Modification Factor of Steel Moment Frame Based on Available Connection Rotation Capacity)

  • 이철호;김건우;송진규
    • 한국지진공학회논문집
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    • 제11권2호
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    • pp.11-17
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    • 2007
  • 현행 내진설계에서 반응수정계수는 탄성 밑면전단력을 저감하여 설계하중 수준을 정의하기 위한 주요 계수로 사용되고 있다. 이제까지 반응수정계수는 공학자들의 경험적인 합의에 의하여 정성적으로 설계기준에 반영하고 있다. 구조시스템에서 반응수정계수와 접합부의 가용 회전능력은 매우 밀접한 관계가 있으며, 본 논문에서는 이러한 접합부의 회전능력과 비선형 푸쉬오버 해석에 기초하여 반응수정계수를 평가하는 방법을 제시하였다. 이를 검증하기 위하여 IBC 2000에 따라 설계된 R3S 골조를 대상으로 제안 방법을 적용하였다. 또한, 다양한 지진파에 대한 비선형 시간이력 해석을 병행하여 가용 회전능력에 의거하여 산정된 반응수정계수의 타당성을 평가한 결과, 본 제안방법에 따라 정의된 반응수정계수가 충분히 보수적임을 확인하였다.

방사선 치료를 받는 자궁경부암 환자의 가족지지와 성격이 삶의 질에 미치는 영향 (A study on the relationship of family support and personality with quality of life in the Patients receiving radiotherapy for cervix cancer)

  • 노영희
    • 대한방사선치료학회지
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    • 제8권1호
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    • pp.149-159
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    • 1996
  • This descriptive correlational study was undertaken in order to investigate the relationship of family support and personality with quality of life in patients receiving radiotherapy for cervix cancer and to provide basic data to help them improve a better quality of life. The subjects for this study Were 80 out-patients undergoing a radiation therapy at C university hospital in K-city, from April, 1992 to October, 1994. The data were obtained using a convenience sampling technique. The tools used for this study were Ro's quality of life scale, Kang's family support scale and Wallston & others health locus of control scale. The collected data were analyzed by the SAS program using percentage, mean, standard deviation, pearson's correlation coefficients. The result were as follows : 1. The total average score of the quality of life of the subjects was 138.95(minimum score 121-maximum score 164), item mean score(range 1-5) was 2.95. The total average score of the family support of the subjects was 32.55 (minimum score 16-maximum score 47), item mean score(range 1-5) was 2.95 The total average score of the health locus of control of the subjects was 37.00 (minimum score 24-maximum score 49), item mean score (range 1-6) was 3.36. 2 The results of the analysis of the relationship between the quality of life scale and the health locus of control were as follows : the total average score in the quality of life of internal locus of control scale was 136.97, the total average score in the quality of life of external locus of control scale was 144.90. 3. There was a significant positive correlation between the health locus of control and the quality of life(r = 0.2927, p<0.01). The result of the analysis of the relationship between the each factor in the quality of life and health locus of control were as follows : There were significant differences between the health locus of control and emotional state factor(r=0.1514, p<0.01), economic life factor(r=0.2560, p<0.05), self-esteem factor(r=0.2289, p<0.05), physical state and function factor(r=0.1455, p<0.05), relationship with neighbors factor(r=0.0754, p<0.05), relationship with family factor (r=0.3324, p<0.01). 4. There was a significant positive correlation between the family support and the quality of life(r=0.459, p<0.001). The result of the analysis of the relationship between the each factor in the quality of life and family support were as follows : there were significant differences between family support and emotional state factor (r=0.3891, p<0.01), self-esteem factor(r=0.2661, p<0.05), relationship with family factor (r=0.4353, p<0.001).

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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) (A Photoelastic Study on Change of Stress Concentration Factor Due to Unsymmetrical Change of Notch Angle)

  • 문장출
    • 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 $140^{\circ}$.

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원료삼 생산수익 결정모형 (Revenue Determination Model of Raw Ginseng Production)

  • 밝훈
    • Journal of Ginseng Research
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    • 제33권3호
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    • pp.240-243
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    • 2009
  • 원료삼 생산에 있어 총수익(R)을 결정하는 4요인 승법 모형을 설정하고 (R=AYQP) 세 농가의 수납실적 수치를 사용하여 총수익 결정식임을 확인하였다. 4요소는 자본요소인 재배면적(A), 기술요소인 단위수량(Y)과 가중평균 품질등급(Q) 그리고 시장요소인 평균등급 가격(P)의 3요소로 해석하였다. 기술요소인 YQ는 자본(A)과 수익(R)의 직선모형에서 기울기가 되어 단위자본의 수익창출계수임을 밝혔다. 수익결정식은 인삼산업의 발전이 재배수량과 품질 향상기술 YQ를 증대시켜 면적(A)을 감소시킴으로서 수익(R)을 높여 시장가격(P)을 낮추는데 있음을 보여주었다.

원-팩터 모형을 이용한 KOSPI200지수 구성종목의 최적 포트폴리오 구성 및 VaR 측정 (Optimal portfolio and VaR of KOSPI200 using One-factor model)

  • 고광이;손영숙
    • Journal of the Korean Data and Information Science Society
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    • 제26권2호
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    • pp.323-334
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    • 2015
  • J. P. Morgan의 RiskMetrics을 기반으로 하는 현행 VaR 모형은 구조적으로 예측된 미래의 경기상황을 반영할 수가 없다. 본 연구에서는 주가의 변동요인인 워너 확률과정을 기업의 고유요인과 경기변동요인으로 구분한 원-팩터 (One-factor) 모형을 제안하여 미래 경기변동 공통요인을 미리 예측하여 반영함에 따라 장기적인 주식 보유기간에도 선제적인 리스크관리를 실시할 수 있도록 한다. 또한 미래 경기변동요인이 예측값으로 고정됨에 따라 포트폴리오를 구성하는 주가들이 서로 독립성을 만족하게 되여 포트폴리오의 분산을 최소화하는 각 주식의 투자금액을 결정하는 것은 물론 포트폴리오 VaR가 개별 VaR의 합으로 분해되어 목표로 하는 최대손실금액에 따른 포트폴리오의 구성을 효율적으로 실시할 수가 있다.

병원영양사의 직무만족요인에 대한 조사연구 (A Study on the Factors of Job Satisfaction of the Dietitians Working in Hospitals)

  • 이현숙
    • Journal of Nutrition and Health
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    • 제29권6호
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    • pp.651-660
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    • 1996
  • The purpose of this study was to examine and analyze the degrees and the influence factors of job satisfaction of dietitians working in hospitals in relation to performance of duty in their works and to provide effective management of hospital dietitians for high quality health and food service in hospital. The questionaire was prepared with reference to the previous studies on job satisfaction of dietitians working in hospitals throughout the nation. 201 dietitians in the country were surveyed. The period of research was from January 20 to February 28, 1995. The results are as follows. 1) In regard to the degree of job satisfaction of hospital dietitians, they showed the highest degree of job satisfaction in the relationships with fellow dietitians followed by worth and self-confidence, aptitude and interests, relationships with cooks, job stability, degree of recognition of the dietitians competence, supervision of the superiors, degree of application of professional knowledge, work load, wage level, degree of recognition of the importance of duty, cooperative relationships with load, wage level, degree of recognition of the importance of duty, cooperative relationships with doctors, degree of performance of clinical work, the number of dietitians, the prromotion system, and welfare system in that order. On the other hand, they showed the highest dissatisfaction with food service facilities. 2) The influence factors on job satisfaction are as follows. (1) Wage factor : Shorter weekday working hours and higher bonuses make greaster job satisfaction (R2=0.3115). (2) Working condition factor : Larger number of monthly holidays(R2=0.5142), shorter weekday working hours(R2=0.1077), longer previous food service experience and computer utilization (R2=0.1432) make greater job satisfaction. (3) Welfare factor : Welfare system (R2=0.4132) and promotion system (R2=0.1624) have to do with computer utilization. Job stability has to do with marital status and computer utilization (R2=0.1165). consequently, those married dietitians who use computers show higher job satisfaction. (4) Human relationship factor : Smaller mumber of patients receiving food makes greater job satisfaction (R2=0.1334). (5) Superivision factor : Shorter weekday working hours and larger number of monthly holidays make greater job satisfaction (R2=0.1709). (6) Achievement factor : Marriage, larger number of dietitians(R2=9.2293), age, larger number of monthly holiday, higher monthly wages and computer utiliazation (R2=0.1088) make greater job satisfaction. (7) Speciality factor : Marriage, longer current hospital tenure, higher position and working in seoul(R2=0.1142) make higher job satisfaction. (8) Job inclination factor : working in general hospitals rather than in oriental hispitals, working in seoul(R2=0.1776) and better bonuses(R2=0.1078)make greater job satisfaction. As a result, the following is suggested for the job satisfaction of hospital dietitions on the basis of this study : hospital dietitians can achieve miximum job satisfaction through smooth relationships with coworkers, and the responsible managers should improve welfare and working conditions for the job satisfaction of hospital dietitians.

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Design parameter dependent force reduction, strength and response modification factors for the special steel moment-resisting frames

  • Kang, Cheol Kyu;Choi, Byong Jeong
    • Steel and Composite Structures
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    • 제11권4호
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    • pp.273-290
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    • 2011
  • In current ductility-based earthquake-resistant design, the estimation of design forces continues to be carried out with the application of response modification factors on elastic design spectra. It is well-known that the response modification factor (R) takes into account the force reduction, strength, redundancy, and damping of structural systems. The key components of the response modification factor (R) are force reduction ($R_{\mu}$) and strength ($R_S$) factors. However, the response modification and strength factors for structural systems presented in design codes were based on professional judgment and experiences. A numerical study has been accomplished to evaluate force reduction, strength, and response modification factors for special steel moment resisting frames. A total of 72 prototype steel frames were designed based on the recommendations given in the AISC Seismic Provisions and UBC Codes. Number of stories, soil profiles, seismic zone factors, framing systems, and failure mechanisms were considered as the design parameters that influence the response. The effects of the design parameters on force reduction ($R_{\mu}$), strength ($R_S$), and response modification (R) factors were studied. Based on the analysis results, these factors for special steel moment resisting frames are evaluated.