• Title/Summary/Keyword: statistical variation

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Exploratory Sensitivity Analysis of Environmental Equity to Spatial to Measures (공간척도 유형에 따른 환경적 형평성의 민감도 분석)

  • Jun, Byong-Woon
    • Journal of the Korean association of regional geographers
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    • v.12 no.4
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    • pp.508-521
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    • 2006
  • The results of environmental equity analysis vary dramatically depending on different methods used. The information and data available to the researcher are also often uncertain and imprecise in empirical studies. A sensitivity analysis approach was used too handle uncertainties and methodological inconsistencies in environmental equity analysis. This paper explores the sensitivity of environmental equity analysis to two spatial measures such as proximity and scale. Two experiments were implemented to evaluate the effects of two spatial measures on the environmental equity analysis using a combination of control and experimental factors. Fulton County, Georgia was selected as a case study area for these experiments. Two major data sets including demographic characteristics and toxic release inventory (TRI) database for the study area in 1990 were integrated into a GIS environment. Two statistical analyses such as independent samples t-test and coefficient of variation were performed to determine the environmental equity in the study area and to compare the relative variability in the socioeconomic characteristics of populations over different spatial measures. The findings from two experiments indicate that the outcomes of environmental equity analysis are slightly sensitive to the buffer distance used to determine the impact zones of TRI facilities, but not to the geographic scale used in the analysis. The findings also suggest that the consequences of these choices can alter spatially and statistically the results in environmental equity analysis.

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The Spatial Variations in Sex Age Structure in the Kyonggi Province (경기지역의 성별 연령구조지수에 관한 공간적 연구)

  • Kwon, Yong-Woo
    • Journal of the Korean association of regional geographers
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    • v.3 no.1
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    • pp.35-50
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    • 1997
  • The purpose of this research seeks to analyze the spatial variations in the sex age structure which have been shown to exist within the study atrea, the Kyonggi province in Korea. In this study it is desired to use the Age Structure Index developed by Coulson in order to describe thi sex age structure of each of 186 tracts that comprise the tracted portion of the Kyonggi province. The mechanics of computing the Age Structure Index are found in the equation describing a linear least squares trend line: y=a+bx. For each census tract, the percentage of the population in each age group(y) was plotted against the middle age of each age group(x). The a is a constant representing the value of y, when x equals zero. The b is the regression coefficient and is a measure of the angle of the slope of the least squares trend line. Thus the value of b is the Age Structure Index for each census tract. The major results of this investigation can be summarized as follows: The spatial distributions of sex age structures in the Kyonggi province are far from random. They have exhibited great regularity with the yonger sex age structures near Seoul and a sharp decline to the older sex age structures out in all derections towards rural region. The results of this investigation should have important general significance for the study of the Kyonggi province Age Structure Index is a flexible, operational definition shich allows sex age structure to be measured, mapped, and incorporated in a wide variety of methods of statistical analysis. Futurer, it has been demonstrated that sex age structure varies spatially within Seoul metropolitan finge and that this variation is relagfed to many other attributes of the population. Especially, Age Structure Index is strongly related to the variables-rate of population growth rate. density, rate of numbers of manufacturing, land price. At the same time, considerably more research is needed before a genmeral body of knowlege concerning sex age structure can be developed.

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A Study on the Long-Term Variations of Annual Maximum Surge Heights at Sokcho and Mukho Harbors (속초와 묵호항의 연간 최대해일고의 장기간 변동성에 대한 고찰)

  • Kwon, Seok-Jae;Moon, Il-Ju;Lee, Eun-Il
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.20 no.6
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    • pp.564-574
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    • 2008
  • This study investigates a long-term variation of annual maximum surge heights(AMSH) and main characteristics of high surge events, which is influenced by the global warming and intensifying typhoons, using sea level data at Sokcho and Mukho tidal stations over 34 years ($1974{\sim}2007$). It is found that the there is a longterm uptrend of the AMSH at Sokcho (8.3 cm/34yrs) and at Mukho (8.7 cm/34yrs), which is significant within 95% confidence level based on the linear regression. The statistical analysis reveals that 53% of the AMSH occurs during typhoon's event in both tidal stations and the highest surge records are mostly produced by the typhoon. It is concluded that the uptrend in the AMSH is attributed by the increasing typhoon activities globally as well as locally in Korea due to the increased sea surface temperature in tropical oceans. The continuous efforts monitering and predicting the extreme surge events in the future warm environments are required to prevent the growing storm surge damage by the intensified typhoon.

Uncertainty evaluation of the analysis of 11-nor-9-carboxy-Δ9-tetrahydrocannabinol in hair by GC-NCI-MS/MS (GC-NCI-MS/MS를 이용한 모발 중 대마 대사체 분석의 측정불확도 평가)

  • Kim, Jin-Young;Lee, Jae-Il;Cheong, Jae-Chul;Suh, Yong-Jun;In, Moon-Kyo
    • Analytical Science and Technology
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    • v.24 no.1
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    • pp.1-9
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    • 2011
  • We described an estimation of measurement uncertainty in quantitative analysis of 11-nor-9-carboxy-${\Delta}^9$-tetrahydrocannabinol (THC-COOH), the metabolite of ${\Delta}^9$-tetrahydrocannabinol, in hair samples by using the bead-assisted liquid-liquid extraction and gas chromatography-tandem mass spectrometric (GC-NCI-MS/MS) detection. Traceability of measurement was established through the use of reference materials, calibrated volumetric tubes, volume measuring devices, and measuring instruments. The analytical results were compared and the different contributions to the uncertainty were evaluated. Inter-day variation was performed by using statistical analysis of several indicative factors. Measurement uncertainty associated with the analyte in real forensic hair samples were estimated using QC data. The major factor of contribution to combined standard uncertainty was inter-day repeatability, while those associated with preparation of analytical standard and also sample of weight were insignificant considering the degree of contribution. Relative uncertainty of relative extended standard uncertainty divided into the measured concentration of the analyte was 17% in a hair sample. The uncertainty of result evaluation will be invaluable to improve quality of the analysis.

A Study on the Diurnal Variation of Endorphin in Rat Brain (백서 뇌내 Endorphin의 일주기 변동에 관한 연구)

  • Jung, Chang-Young;Kim, Ki-Won;Cho, Kyu-Park
    • The Korean Journal of Pharmacology
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    • v.20 no.2
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    • pp.35-47
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    • 1984
  • Contents of immunoreactive ${\beta}-endorphin$ and maximum of $^3H-morphine$ binding was measured in the rat midbrain homogenates from different subgroups at 24 hour interval over 24 hours. Animals were adapted to the light-dark cycle(L : D, 12: 12) or constant darkness (D : D, 12 : 12) for 3 weeks. After the adaptation, 0.5ml of physiologic saline or drug was administered twice a day for 2 weeks. A highly significant circadian rhythm with the peak$(94.8{\pm}7.7\;fmole/mg\;protein)$ at 06:00 and the nadir $(27.6{\pm}2.4\;fmole/mg\;protein)$ at 18:00 was observed in constant of group. Constant dark or treatment of reserpine, pargyline, imipramine, amphetamine and chlorpromazine modified the diurnal rhythm in the time of peak and nadir, shape, phase amplitude and 24 hour mean of ${\beta}-endorphin$ contents. Opiate receptor binding by $^3H-morphine$ also showed highly significant diurnal change in control and constant dark adapted rats. Statistical analysis by one-way analysis of variance and two-way analysis of variance indicates that the·re are highly significant differences between the diurnal change of ${\beta}-endorphin$ in control and those constant dark adapted and drug treated groups. However diurnal change of Maximum $^3H-morphine$ binding is closely related to the change of ${\beta}-endorphin$ contents. The results are interpreted with regard to the circadian rhythm of beta-endorphin contents, its modification by psychoactive drugs and possible mechanism of diurnal change of opiate receptor in brain.

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Molecular Holographic QSAR Model on the Herbicidal Activities of New Novel 2-(4-(6-chloro-2-benzoxazolyloxy)phenoxy)-N-phenylpropionamide Derivatives and Prediction of Higher Activity Compounds (새로운 2-(4-(6-chloro-2-benzoxazolyloxy)phenoxy)-N-phenyl-propionamide 유도체들의 제초활성에 관한 HQSAR 모델과 높은 활성 화합물의 예측)

  • Sung, Nack-Do;Kim, Dae-Whang;Jung, Hoon-Sung
    • The Korean Journal of Pesticide Science
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    • v.9 no.4
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    • pp.279-286
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    • 2005
  • The herbicidal activities against pre-emergence barnyard grass (Echinochloa crus-galli) by a series of new 2-(4-(6-chloro-2-benzoxazolyloxy)phenoxy)-N-phenylpopionamide derivatives as substrate molecule were studied using molecular holographic (H) quantitative structure activity relationships (HQSAR) methodology. From the based on the findings, the higher herbicidal active compounds are predicted by the derived HQSAR model. The best HQSAR model (VI-1) was derived from fragment distinction combination of atoms/bonds in fragment size, $7{\sim}10$bin. The herbicidal activities from atomic contribution maps showed that the activity will be able to increased according to the R-substituents variation of the N-phenyl ring and change of 6-chloro-2-benzoxazolyloxy group. Based on the results, the statistical results of the best HQSAR model (VI-1) exhibited the best pedictability and fitness for the herbicidal activities based on the cross-validated value ($q^2=0.646$) and non cross-validated value ($r^2_{ncv.}=0.917$), respectively. From the graphical analyses of atomic contribution maps, it was revealed that the lowest herbicidal activitics depends upon the 4-(6-chloro-2-benzoxazolyloxy)phenoxy group ($pred.pI_{50}=-3.20$). Particularly, the R=4-fluoro, X=isobutoxy substituent (P2) of (X)-phenoxy-N-(R)-phenylpropionamide derivative is predicted as the highest active compound ($pred.pI_{50}=9.12$).

The Study to Derive Empirical Formula of Rainfall Intencity in Korea (한국에 있어서 강우강도의 효과에 관한 연구)

  • 박성우
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.11 no.2
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    • pp.1644-1650
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    • 1969
  • In the design of general hydrological structures, it is well know that the design flood is of importance in the design of those structures. As the design flood is estimated using the design storm, the design storm is defined by the rainfall intensity itself. Though I had studied and reported many times the reports about the rainfall-intensity in my country, poorly I did not study the long-period variation of the intensity through each section in my country before. But now, in the basin area of the Han river and the Keum river, the self-recorded rainfall charts of the single storms, which are mostly above rainfall amount of 30mm and data of about 4500 with the 150 stationyear, were analyzed, And then, the intensity formula of the hourly unit is estimated using the period from 10 minutes to 5 days. The method to analyze and estimate them, and the final results will be summarized as mentioned below: (i) At first I intended to select out the homogeneous watersheds of three, one in the Han river and two in the Keum river. But I would select the northern and the sourthern river basins, and westward from Koan station, in the basins of the Han river. Also I would select the upstream area, and the downstream area including the watershed of Chungioo, Kongjoo, Chupungryung, and the Mt. Sock, in the basins of the Keum river. Finally, I could find that there couldn't in the Keum river basin. So, I decided out and analyze only river basins of the Han river with limitation mentioned above. (ii) The statistical method to select out the homogenous watersheds is the test of homogeneous variance, and it is estimated from the following equation: $$X_{k1}^2=[{\Sigma}(n_i-1)log\bar{S^2}-\Sigma(n_i-1)log\bar{S^2}]{\times}loge$$ (iii) Actually, each homogeneous watershed has individually its own intensity formula, But I would express them as the actual amount, because the equation of intensity variance is experiential and theoretical equation of the variance. Therefore the caluating equation is actually more convenient in the actual uses. (iv) This report is one of the series for me to give the basis to the actual designs. The cost for this study is provided by the Ministry of Construction. And the designs of the hydrological structures in the watersheds with limitation mentioned above may be concerned with and based upon this report.

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A Study on the Relationship between Individual Patient Behavior, Medical Care Level and Therapeutic Compliance: Community Health Survey (개인 건강행태 및 지역보건의료 수준과 치료순응의 관계: 지역사회 건강조사 바탕으로)

  • Kim, Young-Ran;Lee, Tae-Yong;Park, Chang-Soo
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.5
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    • pp.104-115
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    • 2016
  • Objective: This study was conducted in order to investigate the effects of individual patient behavior regarding the health and medical care level on their therapeutic compliance for people diagnosed with high blood pressure by a physician, in order to evaluate the impact of treatment compliance. In this study, the therapeutic compliance was defined as the hypertension drug cure rate. The current blood pressure controls were persons about 30 years of age diagnosed with high blood pressure by their doctor one month fraction of the people who take more than 20 days (30 days). Methods: The data was analyzed by using the X2-test for different comparisons of the therapeutic compliance in the individual characteristics and using a two-stage multilevel logistic regression to identify the community variance of the related index of high blood pressure therapeutic compliance using the data from 229 adults over the age of 19 in a community health survey conducted in 2010. The Spss 18.0 statistical program was used with HLM 7 (hierarchical linear model) Results: It was found that the rate of therapeutic compliance was affected by the individual health behavior and health and medical care levels. Conclusion: In this study, although the odds ratio of the variable region of the high level of health care, I was able Unlike previous studies and focuses on the personal level of variation found variations in the local health care level was a significant. More studies on multilevel analysis are needed in the future considering regional level data.

Clinical and Statistical Analysis with Age in Cases of Pediatric Burn Patients (소아 화상 환자 2,795례에 대한 연령별 임상 통계학적 분석)

  • Cho, Ki-Hyun;Jang, Young-Chul;Lee, Jong-Wook;Koh, Jang-Hyu;Seo, Dong-Kook;Choi, Jai-Ku
    • Archives of Plastic Surgery
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    • v.38 no.4
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    • pp.445-450
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    • 2011
  • Purpose: The objective of this study is to analyze the epidemiological characteristics of pediatric burn patients and to determine the targets for a pediatric burn prevention program. Methods: A retrospective review of all medical records of acute pediatric burn patients (age < 15 years old) admitted to our hospital between January 2005 and December 2009 was performed. Results: 1472 males and 1323 females were investigated, with a male to female ratio of 1.11 : 1. The greatest number of burn patients were those with an age of 1~2 years (1,463, 52.3%). Scalding burn was the most common cause of injury, which accounted for 2183 (78.1%) patients, followed by contact burns (10.5%), flame burn (4.9%), steam burn (3.6%). Especially steam burn was the second cause of injury in the age under 1 year, while flame burn was the second cause of injury in the age over 7 years. During recent 5 years, incidence of flame burn, steam burn, electrical burn gradually decreased. Variation of seasonal incidence is minimal and most of the patients (2,716 cases, 97.2%) had burns less than 20% TBSA (Total body surface area). The median hospital stay was 18.79 days, and the rate of operation was 28.6% with a high rate in electrical burn (76.2%), flame burn (50.0%), steam burn (46.1%). 6 patients died in this series, which yielded a mortality rate of 0.2%. Conclusion: Prevention efforts should reflect recent study results. Focused prevention program and campaign to make people aware of risk factors and their avoidance is required to reduce the number of burn accidents in children.

Objective and Subjective Quality Characteristics of Pork Longissimus Muscle as a Function of the Ultimate pH

  • Cho, Byung-Wook;Oliveros, Maria Cynthia;Park, Kyoung-Mi;Do, Kyoung-Tag;Lee, Ki-Hwan;Seo, Kang-Seok;Choi, Jae-Gwan;Lee, Moon-Jun;Cho, In-Kyung;Choi, Byoung-Chul;Ryu, Kyeong-Seon;Hwang, In-Ho
    • Food Science of Animal Resources
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    • v.29 no.6
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    • pp.685-694
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    • 2009
  • The aim of the present study was to evaluate the variation in ultimate pH of commercial populations of pure-breed (Landrace, Duroc and Yorkshire) pig's longissimus muscles and their effect on objective meat quality traits and sensory characteristics. Fifty boars were sampled from 184 pigs, which were reared at three breeding farms and slaughtered at a commercial abattoir. The selection was determined based on ultimate pH, and animals were segregated into three groups: low pH (pH $\leq$ 5.5, n=13), medium pH (pH 5.5 to 5.6, n=18) and high pH (pH $\geq$ 5.6, n=16). The breeds had no significant effects; however, pigs with a higher ultimate pH had significantly (p<0.05) higher intramuscular fat content, lower level of polyunsaturated fatty acids, lower level of lipid oxidation and higher eating quality compared to those with lower ultimate pH. As the ultimate pH increased, the relative proportion of C14:0, C16:0 and C18:1 increased while C18:2n6 and C20:4n6 decreased. The present study demonstrates that the economic value of pigs can be characterized by the ultimate pH and/or intramuscular fat content. However, these results do not necessarily indicate that a high ultimate pH directly corresponds to high intramuscular fat content and vice versa.