• Title/Summary/Keyword: Environment deviation

Search Result 671, Processing Time 0.034 seconds

Monthly Fluctuation of the Han River Water Quality (한강수질의 월변동성에 관한 연구)

  • Yoo, Ho-Sik
    • Journal of Korean Society on Water Environment
    • /
    • v.20 no.4
    • /
    • pp.352-356
    • /
    • 2004
  • Variations of water quality parameters were investigated for last 13 years in Han river. Deviation from 3 month moving average was suggested for the variation analysis. Many parameters of mainstream and tributaries showed similar monthly fluctuations. Suspended solid of mainstream showed higher fluctuation than that of tributaries due to summer flood. Contrarily, the organic parameters such as BOD, COD, and TN showed lower fluctuations in the mainstreams. The magnitude of deviation was in the order of pH < DO, COD, temp. < BOD, TN < TP, SS. Strong correlation was found in BOD data of adjacent sites. Main sites showed low deviation in comparison to adjacent common sites of mainstream (1:2.4). Mainstream showed low deviation in comparison to tributaries (1:1.7). Seasonal tendency of monthly BOD was confirmed using autocorrelation function. The deviation was in inverse proportion to the magnitude of BOD.

Optimum PN Code Acquisition Method using Mean Deviation of Correlator in DS-CDMA Systems (직접대역확산 방식에서 상관기 출력의 평균편차를 이용한 최적 PN 코드획득 방법)

  • Ryu, Yeong-Jae
    • Journal of Satellite, Information and Communications
    • /
    • v.2 no.1
    • /
    • pp.1-6
    • /
    • 2007
  • In this paper, we proposed new algorithm that improves the acquisition performance of the PN code searcher used in DS-CDMA systems. Using the mean deviation computed from the correlator output of the PN code searcher, it is possible to estimate received channel environment. To satisfy the required acquisition performance in estimated channel environment, the PN code searcher changes the correlator tap size adaptively. Proposed algorithm shows improved performance compared with conventional algorithm using the fixed correlator tap size.

  • PDF

The Relationships among the Degree of Quality Cost Deviation, Quality Management Activities and Performance (품질비용 발생편차와 품질관리활동 그리고 성과간의 관계:품질성과와 납기성과를 중심으로)

  • 김달곤;김순기;정순여
    • Journal of Korean Society for Quality Management
    • /
    • v.31 no.4
    • /
    • pp.1-18
    • /
    • 2003
  • Quality is a critical competitive factor in today's environment because of the impact of quality on costs and delivery. Many companies regard quality as a key concept of company strategy in order to achieve the competitive edge. Measuring and reporting quality cost is the first step in quality management program. The supposition of quality cost model is that investment in prevention activities will bring rewards from reduced failure costs, and that further investment in prevention activities will show profits from reduced appraisal costs. In this study, the degree of quality cost deviation is conceptualized. This means a deviation between the ideal and present ranking in the amounts of quality cost categories. This study analysed that the effect of its deviation on quality management activity and performance variables. However, there are no difference in these variables. The major reason is that most of companies are endeavoring for quality management but operating quality cost system unsystematically. The review against a prevention and appraisal activity is necessary.

Variance Analysis of RCP4.5 and 8.5 Ensemble Climate Scenarios for Surface Temperature in South Korea (우리나라 상세 기후변화 시나리오의 지역별 기온 전망 범위 - RCP4.5, 8.5를 중심으로 -)

  • Han, Jihyun;Shim, Changsub;Kim, Jaeuk
    • Journal of Climate Change Research
    • /
    • v.9 no.1
    • /
    • pp.103-115
    • /
    • 2018
  • The uncertainty of climate scenarios, as initial information, is one of the significant factors among uncertainties of climate change impacts and vulnerability assessments. In this sense, the quantification of the uncertainty of climate scenarios is essential to understanding these assessments of impacts and vulnerability for adaptation to climate change. Here we quantified the precision of surface temperature of ensemble scenarios (high resolution (1km) RCP4.5 and 8.5) provided by Korea Meteorological Administration, with spatiotemporal variation of the standard deviation of them. From 2021 to 2050, the annual increase rate of RCP8.5 was higher than that of RCP4.5 while the annual variation of RCP8.5 was lower than that of RCP4.5. The standard deviations of ensemble scenarios are higher in summer and winter, particularly in July and January, when the extreme weather events could occur. In general, the uncertainty of ensemble scenarios in summer were lower than those in winter. In spatial distribution, the standard deviation of ensemble scenarios in Seoul Metropolitan Area is relatively higher than other provinces, while that of Yeongnam area is lower than other provinces. In winter, the standard deviations of ensemble scenarios of RCP4.5 and 8.5 in January are higher than those of December. Especially, the standard deviation of ensemble scenarios is higher in the central regions including Gyeonggi, and Gangwon, where the mean surface temperature is lower than southern regions along with Chungbuk. Such differences in precisions of climate ensemble scenarios imply that those uncertainty information should be taken into account for the implementation of national climate change policy.

The Effect of the Physical Therapy Treatment Room Environment Using Microwave Diathermy on the Autonomic Nervous System of Human Body (극초단파치료기를 사용하는 물리치료실의 환경이 물리치료사의 인체자율신경계에 미치는 영향)

  • Shin, Han-Ki;Lee, Tae-Kyu;Jun, Je-Yoon;Kim, Ju-Seung;Kang, Jong-Ho
    • Journal of the Korean Society of Physical Medicine
    • /
    • v.10 no.1
    • /
    • pp.37-43
    • /
    • 2015
  • PURPOSE: The purpose of this study is to investigate the effect of the physical therapy treatment room environment using microwave diathermy on the autonomic nervous system of human body. METHODS: Participants were 24 healthy adults. Standard deviation of all normal R-R intervals(SDNN), root mean square of successive differences(RMSSD), low frequency(LF), high frequency(HF), LF/HF ratio were compared in microwave irradiation and non-irradiation group. Data were analyzed in Wilcoxon's signed-ranks test and Mann-Whitney U test. RESULTS: Standard deviation of all normal R-R intervals (SDNN), root mean square of successive differences (RMSSD), low frequency(LF), high frequency(HF), LF/HF ratio were not significantly different in microwave irradiation group. Standard deviation of all normal R-R intervals(SDNN), root mean square of successive differences (RMSSD), low frequency(LF), high frequency(HF), LF/HF ratio were not significantly different in microwave non-irradiation group. Standard deviation of all normal R-R intervals(SDNN), root mean square of successive differences (RMSSD), low frequency(LF), high frequency(HF), LF/HF ratio were not significantly different between two groups. CONCLUSION: There was no significant change in the sympathetic nervous system and parasympathetic nervous system regardless of the presence of microwave irradiation. There was no significant change in the autonomic nervous system adaptability regardless of the presence of microwave irradiation.According to this study, microwave diathermy does not have significant effect on the autonomic nervous system.Future study is necessary to investigate the long term effect of the physical therapy treatment room environment using microwave diathermy on the autonomic nervous system of the human body.

A Study on the Optimization of Temperature Deviation of Loads in Smart Reefer Container (스마트냉동컨테이너의 적재부 온도 편차 최적화에 관한 연구)

  • SangWon Park;TaeHoon Kim;DoMyung Park;DongSeop Han
    • Journal of Korea Society of Industrial Information Systems
    • /
    • v.28 no.6
    • /
    • pp.83-90
    • /
    • 2023
  • In a reefer container, temperature deviation occurs between the front of the loading part with the refrigerator and the rear of the loading part with the container door due to the external environment. In particular, this temperature deviation in the transport of fresh cargo has a great influence on the freshness of the cargo. In this study, we propose a method to minimize the temperature deviation by partially shielding the T-Floor to reduce the temperature deviation and evaluating the effect of the T-Floor shielding rate on the temperature change of the reefer container loading part. The subject of the experiment was a 40 feet smart reefer container, and the T-Floor shielding rates were set to 0%, 50%, 60%, 70%, and 80%. As a result of the experiment, it occurred differently in the temperature deviation of the reefer container loading part according to the shielding rate, and it was confirmed that the temperature deviation was the most uniform when the shielding rate was 60%. By minimizing the temperature deviation of the loading part, it is possible to prevent corruption and cold damage of cargo during transportation of fresh cargo by using the smart reefer container.

Surface Micro-Climate Analysis Based on Urban Morphological Characteristics: Temperature Deviation Estimation and Evaluation (도시의 지표형태학적 특성에 기반한 지면미기후 분석: 기온추정 및 평가)

  • Yi, Chaeyeon;An, Seung Man;Kim, KyuRang;Kwon, Hyuk-gi;Min, Jae-Sik
    • Atmosphere
    • /
    • v.26 no.3
    • /
    • pp.445-459
    • /
    • 2016
  • Air temperature deviation (ATD) is one of major indicators to represent spatial distribution of urban heat island (UHI), which is induced from the urbanization. The purpose of this study is to evaluate the accuracy of air temperature deviation about Climate Analysis Seoul (CAS) workbench, which had developed by National Institute Meteorological Science and TU Berlin. Comparison and correlation analysis for CAS ATD including meso-scale air temperature deviation, local-scale air temperature deviation, total air temperature deviation, surface heat flux deviation, cold air production deviation among meso-scale numerical modelling variable in 'Seoul Region', micro-scale numerical modelling in 'Detail Region', and CAS workbench variable using observation data in ground stations. Comparison between night time OBS ATD and CAS ATD show that have most close values. Most of observations ($dT_{max}$ and $dT_{min}$) have highly positive ($dT_{SHP}$, $dT_{CA}$, MD, TD, $f_{BS}$, $f_{US}$, $f_{WS}$, $h_B$) and negative ($f_{VS}$, $f_{TV}$, $h_V$, Z) correlations. However, CAS workbench needs further improvement of both observational framework and analytical framework to resolve the problems; (1) night time OBS ATD of has closer values in compare with at high rise mountain area and (2) correlations are very dependable to meteorological scale.

A Study on the Correction Method for Deviations and Variations of Digital Magnetic Compass (디지털 자기 컴퍼스의 자차와 편차 수정에 관한 연구)

  • Yim, Jeong-Bin;Saha, Rampadha
    • Proceedings of KOSOMES biannual meeting
    • /
    • 2006.11a
    • /
    • pp.137-141
    • /
    • 2006
  • To consider the practical use of a ship's Digital Compass in earth's magnetic field high accurate Deviation and 얘 nation are required to obtain ship's true bearing. Variation can be obtain with World Magnetic Model (WMM) using the Earth's spherical harmonic model of the main field and of the secular variation at any location around the earth. Deviation can be obtain with deviation analysis and synthesis method based on the Poisson equations. As results of deviation and variation corrections to the Digital Compass, high accurate true bearing is obtained. This experiments are carried out during in the navigation of training ship 'SAE-NU-RI'.

  • PDF

A Time Dependent Analysis of Thermal Environment in Beehouse

  • Lee, Suk-Gun;Li, Zhenhai;Choi, Kwang-Soo
    • Proceedings of the Korean Society for Bio-Environment Control Conference
    • /
    • 1997.11a
    • /
    • pp.20-26
    • /
    • 1997
  • The design or analysis of beehouse inside temperature environment based on steady heat transfer theory causes much deviation and theoretically it is impossible to control the inside temperature lower than the outside temperature under the condition that the bee produces heat and no cooling equipment is installed. But in practical use of beehouse, the inside temperature is somehow lower than the outside temperature because of the heat inertia of concrete floor. (omitted)

  • PDF

Evaluation of the Horizontal and Vertical Dispersion Coefficients for the Urban Area (都市地域의 垂直, 水平 擴散係數 算定)

  • 羅振均;金良均;權寧洙
    • Journal of Korean Society for Atmospheric Environment
    • /
    • v.2 no.1
    • /
    • pp.23-31
    • /
    • 1986
  • Meteorological Measurement was performed for evaluation of the horizontal vertical standard deviation $(\sigma_y, \sigma_z)$, surface roughness length and stmospheric stability during the period of March to October 1985 The major results are as follows; 1) The average value of surface roughness length was 144cm at NEPI. 2) In frequency distribution of atmospheric stability, neutral state (D class) was dominent in Seoul (29%) and Pusan (30%). Unstable states (A. B. C. class) were 26% in Seoul and 24% in Pusan. Also, stable states (D. E. F class) were 74% in Seoul and 76% in Pusan. 3) Standard deviations of horizontal ad vertical direction were evaluated as a function of downwind distance and atmospheric stability at NEPI, Jamsil and Pujeondong (Pusan). Standard deviation of horizontal direction was largest at NEPI among 3 areas because of mechanical turbulence resulting from difference of surface roughness length.

  • PDF