• Title/Summary/Keyword: variation rate

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Analysis of Related Factors and Regional Variation of Mortality in Seoul (서울특별시 사망률 변이 및 관련 특성 분석)

  • Kim, Sooyeon;Kim, Ji Man;Park, Chong Yon;Lee, Chang-Woo;Lee, Sang Gyu;Shin, Euichul
    • Health Policy and Management
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    • v.28 no.1
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    • pp.15-22
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    • 2018
  • Background: Health is affected by various local factors. This study aims to investigate the age-standardized mortality variation of Seoul as well as the characteristics of the factors related to the mortality variation. Methods: The Korea Community Health Survey data, Seoul Survey data, Seoul statistics, and e-regional indicators of the National Statistical Office were used. To investigate the basic boroughs standardized mortality variation in Seoul, external quotient, coefficient of variation (CV), and systematic component of variation (SCV) values were suggested; correlation analysis and multiple regression analysis were conducted to investigate the characteristics related to standardized mortality rate. Results: The highest and the lowest standardized mortality rate of Seoul by boroughs had as much as 1.4 times difference; a low level of variation was shown in CV by 8.2; and was shown in SCV by 79. As a result of the multiple regression analysis of the factors that affect standardized mortality variation, the higher the rate of householders with college or higher, the lower the standardized mortality rate, and the higher the high-risk drinking rate, the higher the standardized mortality rate. Of the two, the rate of householder with a degree equivalent or higher than college was shown to have the biggest impact, followed by high-risk drinking rate. Conclusion: We found a variation in age-standardized mortality rate of boroughs in Seoul. The results suggest that policy makers should take into account socioeconomic environmental characteristics of community in developing community-based health promotion rather than focusing on lifestyle changes of residents.

A Study of Thermal Performance Evaluation Index for Building (건물의 열성능 평가 지표에 관한 연구)

  • Kim, Mi-Hyun;Suh, Seung-Jik
    • Journal of the Korean Solar Energy Society
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    • v.27 no.4
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    • pp.67-75
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    • 2007
  • This study intends to the adequacy inspection of the room temperature variation rate that is available in the building heat performance evaluation index, so we performed the sensitivity analysis about the room temperature variation rate and the energy consumption in the room. For these purpose, we supposed the models which are composed of the various window area, insulation thickness and ventilation rate. Then we analyzed the simulation using the ESP-r and Seoul weather data. In this research, the pattern of the increasing & decreasing rate of annual load according to the change of the various design factors is similar to the pattern of increasing & decreasing rate of not the K-values but the room temperature variation rate. Also we derive the optimum value of the various design factors and the room temperature variation rate in this analysis model. Further study is to be required the development of convenient tool to use in the real design.

The Study of the Variation of Strain Rate Sensitivity Index depending on the Strain and Microstructural Observations of AZ31 Mg Alloy Sheet (변형율에 따른 AZ31 합금의 변형율 속도 민감도 지수 변화와 미세조직 특성에 관한 연구)

  • Kim, D.O.;Kang, C.W.;Lee, S.Y.
    • Transactions of Materials Processing
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    • v.20 no.7
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    • pp.498-503
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    • 2011
  • The strain rate sensitivity index, m, plays an important role in plastic deformation at elevated temperatures. It is affected by strain rate, temperature, and the microstructure of the material. The strain rate sensitivity index has been used as a constant in numerical analysis of plastic forming at a specified strain rate and temperature. However, the value of m varies as deformation proceeds at an elevated temperature and a certain strain rate. Thus, in this present study, the value of m has been characterized as a function of strain by multiple tensile jump tests for AZ31 magnesium alloy sheet, and the variation of m has been discussed in conjunction with the microstructural observations before and after deformation. The experimental results show that the variation of m is dependent on the temperature and strain rate. Grain growth with dynamic recrystallization also affects the variation of m.

A Study on Prediction of Sediment and Riverbed Variation According to Sediment Transportation Functions (유사량 산정공식에 따른 유사 및 하상변동 예측에 관한 연구)

  • Go, Su Hyeon;Song, In Ryeol;Kim, Chang Seok
    • Journal of Environmental Science International
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    • v.13 no.3
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    • pp.263-277
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    • 2004
  • The purpose of this study is to analyze the characteristics of riverbed variation due to the sediment protection weir located on the estuary of the main stream of Taehwa river using I-D finite difference model, HEC-6 model, and the followings are the results of estimating sediment transport rate, amount of scour or deposition, and accumulated amount of deposit according to before and after of the sediment protection weir removal with various flow rates in the channel. Ackers-White transport function produced the greatest sediment transport rate while Meyer-Peter showed the smallest sediment transport rate at the most down stream area of the watershed through the sediment transport rate analyses for various flow rates according to the existence or nonexistence of the sediment protection weir. Toffaleti's and Colby transport function were closest to the average value, and the difference among the results of the sediment transport functions showed up to 8~9 times. Duboy's transport function produced the greatest riverbed variation while Toffaleti's showed the smallest variation through the riverbed variation analyses according to the existence or nonexistence of the sediment protection weir. Yang's was closest to the average value, and the difference among the results of the riverbed variation analyses ranged from 1.4 times to 11 times. It is thought that a sediment transport function must be selected very carefully with respect to the criteria of sediment yield estimation because the analysis results of the sediment transport rate and riverbed variation according to flow rates showed significant differences among the sediment transport functions, and the differences of sediment transport rate and riverbed variation according to the various sediment transport functions decreased as the flow rate increased.

Flow Direction Characteristics in the Vicinity of the Spark Plug in an S. I. Engine

  • Han, Sung-Bin;Chang, Yong-Hoon;Chung, Yon-Jong
    • Journal of Mechanical Science and Technology
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    • v.14 no.8
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    • pp.891-899
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    • 2000
  • The flame speed may be decomposed into the burning speed and the flame transport speed. The flame transport speed is affected considerably by the flow direction, variation rate of flow direction, and flow speed in the combustion chamber. Especially, the flow direction and the variation rate of flow direction at the spark plug location during the ignition period have an important effect on the ignition process and the early flame propagation process. We measured the flow direction component and the variation rate of flow direction with a hot wire probe at the spark plug location. It was shown that the representative flow direction of ignition period is the right-vertical direction of crank shaft and it was used to investigate the variation rate of flow direction.

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Sliding Mode Control with Target Variation Rate of Lyapunov Function for Seismic-Excited Structures (Lyapunov함수의 목표 변화율을 이용한 가진된 건물의 슬라이딩 모드 제어)

  • 이상현
    • Proceedings of the Earthquake Engineering Society of Korea Conference
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    • 2001.04a
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    • pp.163-171
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    • 2001
  • This paper presents sliding mode control(SMC) method using target variation rate of Lypunov Function. SMC keeps the response of structure in sliding surface where structure is stable. It can design both linear controller and bang-bang controller. Linear control of previous research, however, can not make most of the performance of controller, because it is designed to satisfy the condition that the variation rate of Lyapunov function is minus. Also, incase of bang-bang controller, unnecessary large control force is generated. Presented method can utilize the capacity of controller efficiently by prescribing the target variation rate of Lyapunov function. Numerical simulation results indicate that the presented control methods can reduce the peak response larger than linear control, and it has control performance equivalent to bang-bang control.

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Distortion Variation Minimization in low-bit-rate Video Communication

  • Park, Sang-Hyun
    • Journal of information and communication convergence engineering
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    • v.5 no.1
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    • pp.54-58
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    • 2007
  • A real-time frame-layer rate control algorithm with a token bucket traffic shaper is proposed for distortion variation minimization. The proposed rate control method uses a non-iterative optimization method for low computational complexity, and performs bit allocation at the frame level to minimize the average distortion over an entire sequence as well as variations in distortion between frames. The proposed algorithm does not produce time delay from encoding, and is suitable for real-time low-complexity video encoder. Experimental results indicate that the proposed control method provides better visual and PSNR performances than the existing rate control method.

Speech Rate Variation in Synchronous Speech (동시발화에 나타나는 발화 속도 변이 분석)

  • Kim, Miran;Nam, Hosung
    • Phonetics and Speech Sciences
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    • v.4 no.4
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    • pp.19-27
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    • 2012
  • When two speakers read a text together, the produced speech has been shown to reduce a high degree of variability (e.g., pause duration and placement, and speech rate). This paper provides a quantitative analysis of speech rate variation exhibited in synchronous speech by examining the global and local patterns in two dialects of Mandarin Chinese (Taiwan and Shanghai). We analyzed the speech data in terms of mean speech rate and the reference of "Just Noticeable difference (JND)" within a subject and across subjects. Our findings show that speakers show lower and less variable speech rates when they read a text synchronously than when they read alone. This global pattern is observed consistently across speakers and dialects maintaining the unique local variation patterns of speech rate for each dialect. We conclude that paired speakers lower their speech rates and decrease the variability in order to ensure the synchrony of their speech.

Analysis of Series Arc-Fault Signals Using Wavelet Transform From Non-linear Loads (웨이블렛 변환을 이용한 비선형 부하 전원선에서의 직렬 아크고장 신호 분석)

  • Bang, Sun-Bae;Park, Chong-Yeun;Jang, Mog-Soon;Choi, Won-HO
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.57 no.8
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    • pp.1470-1477
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    • 2008
  • In this paper, a new detection method of series arc-fault signals occurring at the wiring of home appliances is proposed. The discrete wavelet transform was used for the numerical analysis of the variation rate in peak, RMS, noise energy, shoulder of the arc-fault current wave. As a results, the arc distinction threshold value of these variation rates was about 0.1 in most cases. The arc-fault current of the loads with the active PFC circuit showed a high rate of variation in noise energy and shoulder, but arc-fault current of the loads without the active PFC circuit showed a high rate of variation in peak and RMS. The arc fault current in resistive loads showed a high rate of variation in shoulder.

Characteristics of Indoor Air Quality and Local Supply Index with a Variation of Supply ${\cdot}$ Exhaust Airflow rate (환기량 변화에 따른 실내공기질과 국소급기지수 특성)

  • Han, Chang-Woo;Noh, Kwang-Chul;Oh, Myung-Do
    • Proceedings of the SAREK Conference
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    • 2005.11a
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    • pp.21-26
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    • 2005
  • We performed the numerical analysis on the characteristics of indoor air quality and local supply index with a variation of supply · exhaust airflow rate. We analyzed the local supply index and carbon dioxide concentration at the room and breathing zone with respect to the variation of the supply · exhaust airflow rate. From the numerical results, we found that local supply index was affected but carbon dioxide concentration was hardly affected by the variation of the airflow rate in the room. And we also knew that carbon dioxide concentration was raised in despite of the increment of the supply airflow rate in the breathing zone. After this study it is necessary to analyze the local exhaust index when we evaluate the state of the ventilation in the room.

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