• 한국환경과학회지
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• 제12권1호
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• pp.23-34
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• 2003

Urban air quality is usually worse than that of rural counterpart. The contrasting atmospheric properties seem to be direct result of different urban-rural air pollutant emission. Hence, the emission estimation of air pollutants plays an important role to the atmospheric environmental management. The main purpose of this study is to find out the temporal and spatial distribution of air pollutant emission in Daegu area. For the study, the Daegu statistical yearbook and data of waste facilities and the report on traffic survey issued by Daegu metropolitan city and the statistical yearbook on the road capacity issued by the ministry of construction and transportation are used. Each item for the emission estimation is $SO_2$, CO, HC, $NO_x$, PM-10 from point, line and area source. The result were as follow; (1) The air pollutants with the highest amount of emission from the emission source is CO followed by $NO_x$, $SO_2$, PM-10, HC in descending order of magnitude. (2) The annually totaled air pollutant emission consists of 81%(73,185 ton/year) of line, 11%(9,589% ton/year) of area and 8%(7,445 ton/year) of point source in Daegu. Air polluant emission was mainly due to line sources. (3) High-emission of the air pollutants of line source appeared ariond Bukgu, Dalseonggun, Dongu and Seogu ; the areas with highway networks.

• Asian-Australasian Journal of Animal Sciences
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• 제24권8호
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• pp.1041-1047
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• 2011

Data on 2,365 Mecheri sheep (1,201 males and 1,164 females), maintained at the Mecheri Sheep Research Station, Pottaneri, India, and recorded between 1979 and 2006, were analysed to study the growth related traits and their genetic control. The body weights at different ages (i.e. at birth, weaning (3 months), 6, 9 and 12 months) were recorded and collected from the birth and growth registers maintained in the farm. The average weights of Mecheri sheep at birth, and at 12 months of age were $2.24{\pm}0.01$ and $16.81{\pm}0.15$ kg respectively. The pre- and post-weaning average daily weight gains were $63.84{\pm}0.75$ and $29.52{\pm}0.43$ g respectively. Study revealed a significant difference with the period of lambing on body weight, weight gain and efficiency in weight gain at different stages of growth. Males were heavier and had a higher weight gain than females at almost all stages of growth and the differences tended to increase with age. The direct heritability estimates increased from birth to six months of age and then decreased. The direct heritabilities of all body weights at different stages of growth were low to moderate in magnitude and the values at birth, weaning, six, nine and 12 months of age were 0.08, 0.17, 0.21, 0.13 and 0.10 respectively. For the estimation of heritability at birth and three months body weights, the direct additive genetic and maternal additive genetic effects have to be taken into account and for the estimation of six months weight, the direct additive genetic and maternal permanent environmental effects have to be included in the model. The estimates of heritability, phenotypic and genetic correlations among the different body weights indicated that the selection for improving the body weights at different traits should be done on the basis of three or six months weight because of higher heritability estimates and having higher genetic correlations with other traits.

• 한국정보통신학회논문지
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• 제12권5호
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• pp.900-905
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• 2008

직류 성분 편차와 반송 주파수 편차가 모두 존재하는 OFDM 시스템에서의 비트 오류율 특성을 분석한다. 16-QAM 변조 방식을 이용하며 파일럿 심볼을 사용하여 채널을 추정하는 실제 OFDM 시스템에서 직류 성분 편차 및 반송 주파수 편차의 크기들에 따라 변화되는 비트 오류율 특성을 구한다. 분석 결과를 이상적인 OFDM 시스템의 성능과 비교한 결과, 반송 주파수 편차의 크기는 0.01 이하가, 그리고 직류 성분 편차의 크기는 0.007 이하가 요구되는 것을 알 수 있다.

• 대한토목학회논문집
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• 제9권4호
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• pp.93-102
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• 1989

유역(流域)의 저축효과(貯蓄效果)와 하도(河道)에서의 평행이동효과(平行移動效果)를 고려하여 유역(流域)에서의 연체시간(運滯時間)을 결정하였으며, 평행이동효과(平行移動效果)는 유역 비선형성(非線型性)을 나타내기 위하여 흐름단면적과 유출량의 관계를 지수함수(指數函數)로 표시하였고, 수로(水路)길이의 영향을 고려하기 위하여 흐름단면과 하도거리와의 관계를 1차식(次式)으로 표시하였다. 운체시간(運滯時間)에 관한 매개변수(媒介變數)들을 수로망(水路網)크기로 부터 결정하였으며, 수로선분(水路線分)에 의하여 형성되는 소류역내(小流域內)의 유효강우(有效降雨)를 본류하도(本流河道)를 통하여 저수지(貯水池) 추적(追跡)을 실시함으로써 금강수계내(錦江水系內)의 지류(支流)인 보청천유역(報靑川流域)의 산역(山域)과 기대지점(其大地點)에서의 직접유출(直接流出)을 예측(豫測)하였다.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2010년도 추계학술대회 논문집
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• pp.491-496
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• 2010

The direct design modification of problematic component is disallowed in order to sacrifice other major factors such as a stability or a major performance. So, the best design policy is to risvise the immature structural medchanism under the minimal design change as soon as possible. For this paper presents a new design sensitivity analysis based on transmissibility rtio (TR) of response acceleration to find a proper candidate for the minimal design modification. The new sensitivity analysis is based on the fact that the sensitivity of TR over a small design change is inversly proportinal to the magnitude of TR. The theory of proposed design sensitivity analysis is simulated with the variance of TR over a dynamic change. Then, new methodology is appplied for a linear elastic specimen to detect the most sensitive node over a design change using measured accleration data during uni-axial vibration test, The physical verification of the sensitivity method is conducted on the CAE model of a linear elastic specimen by adding concentration mass and the vibration fatigue of the simple specimen is analyzed to estimate the relationship between fatigue behaviors and sensitivity consequences.

• Journal of Ecology and Environment
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• 제30권2호
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• pp.201-207
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• 2007

Researchers have used a variety of methods to measure patterns of animal movement, including the use of spatial data (mapping the position of a moving animal at specified intervals) and direct estimation of travel path length by pacing under a moving animal or group. I collected movement data from five groups of siamangs (Symphalangus syndactylus) using two different methods concurrently to estimate the effects of the method of data collection on estimates of daily path length (DPL). Estimates of DPL produced from spatial data collected at 15-minute intervals were 12% lower than estimates of DPL produced by pacing under the traveling animal. The actual magnitude of the difference was correlated with the travel distance, but there was no correlation between the proportional difference and the travel distance. While the collection of spatial data is generally preferable, as spatial data permit additional analyses of patterns of movements in two or three dimensions, the relatively small difference between the DPL's produced using different methods suggests that pacing is an acceptable substitute where the collection of spatial data is impractical. I also subsampled the spatial data at increasing time intervals to assess the effect of sampling interval on the calculation of daily path lengths. Longer sampling intervals produced significantly shorter estimates of travel paths than shorter sampling intervals. These results suggest that spatial data should be collected at short time intervals wherever possible, and that sampling intervals should not exceed 30 minutes. Researchers should be cautious when comparing data generated using different methods.

• Asian-Australasian Journal of Animal Sciences
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• 제21권10호
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• pp.1395-1403
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• 2008

The objective of the present study was to estimate genetic parameters for economic traits in Markhoz goats. Data collected from 1993 to 2006 by the Markhoz goat Performance Testing Station in Sanandaj, Iran, were analyzed. The traits recorded as body weight performance at birth (BW), weaning (WW), six month (6MW), nine month (9MW), yearling (YW) and yearling fleece weight (YFW) were investigated. Least square analyses were used for estimation of environmental effects. Genetic parameters were estimated with single and multi trait analysis using restricted maximum likelihood (REML) procedures, under animal models. By ignoring or including maternal additive genetic effects and maternal permanent environmental effects, five different models were fitted for each trait. The effects of sex, type of birth, age of dam and year of birth on the all body weights were significant (p<0.01), but had no effects on YFW except year of birth. Age of kids had significant influences on WW and 6MW (p<0.01). A log likelihood ratio test was carried out for choosing the most suitable model for each trait. Total heritability estimates for YFW and growth traits varied from 0.16 for YFW and WW to 0.41 for YW. For all traits, maternal heritability was lower than direct heritability, ranging from 0.06 for BW to 0.01 for 6MW and 9MW. The magnitude of $c^2$ was more substantial for BW than the others, and relative importance was reduced from 0.12 for BW to 0.04 for 9MW. The direct additive genetic correlations estimates were positive and varied from 0.21 between BW-YW to 0.96 between WW-6MW. Direct additive genetic correlations between YFW and body weight traits were positive and ranged from 0.14 between BW-YFW to 0.67 between 6MW-YFW. For all traits, the corresponding estimates for phenotypic correlation were positive and lower than genetic correlations. The maternal additive genetic correlations between various traits were varied and ranged from -0.19 between 9MW-YFW to 0.96 between 6MW-9MW. The estimates of the maternal permanent environmental correlations between various traits were positive and ranged from 0.33 between WW-YFW to 0.93 between WW-6MW. Also, the environmental correlations between various traits ranged from 0.01 between BW-YFW and WW-YFW to 0.70 between 9MW-YW. Estimates of genetic parameters for various traits in this study confirm that selection should be applied on WW for genetic improvement in Markhoz goats.

• 대한토목학회논문집
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• 제32권3D호
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• pp.205-212
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• 2012

일반국도 교통량조사는 크게 수시조사와 상시조사로 나누어진다. 수시조사는 상시조사와 달리 표본조사로 시행되고 있으며 조사 시기에 따라 AADT에 대한 오차의 크기가 달라진다. 따라서 본 연구에서는 수시조사의 AADT 추정의 정확도를 높이기 위하여 도로 유형별로 AADT와의 오차가 작은 수시조사 시기를 파악하고자 하였다. 그리고 상시조사는 조사 지점에 설치되어 있는 장비의 고장이나 오작동 등으로 인하여 교통량 자료가 정상적으로 수집되지 않아 해당 지점의 교통량 변동을 제대로 파악할 수 없는 경우가 자주 발생한다. 따라서 본 연구에서는 장비 설치년도, 중차량 비율 등이 장비의 고장이나 오작동의 원인이 될 수 있는 지를 장비 유지보수 횟수와의 상관관계 분석을 통하여 파악하고자 하였다.

• 터널과지하공간
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• 제19권3호
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• pp.226-235
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• 2009

터널내 자연환기력은 터널의 정상운영시 뿐만 아니라 터널내 화재와 같은 비상시에 기류 유동상의 심각한 문제를 야기할 수 있다. 따라서 자연환기력의 영향은 터널 환기 및 방재시스템 설계시에 반드시 고려하여야한다. 자연환기력의 결정에 영향을 미치는 변수에는 지형, 기상, 터널의 물리적 특성에 관련된 다양 변수들이 포함된다. 그러나 이들 변수간의 정량적인 관계의 이해가 복잡하여 현재 어떤 나라에서도 국가기준에 자연환기력의 예측방법을 제시하고 있지 않다. 본 논문에서는 국내 고속도로터널을 대상으로 자연환기력의 정량화 연구를 수행하였다. 정량화를 위하여 첫째, 양 갱구의 기압차 측정방법, 둘째, 피스톤효과에 의한 영향을 제거하는 방법, 셋째, 기압장벽고 방법을 적용하였다.

• Asian-Australasian Journal of Animal Sciences
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• 제31권9호
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• pp.1407-1414
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• 2018

Objective: The aim of this study was to estimate (co) variance components and genetic parameters for categorical carcass traits using Bayesian inference via mixed linear and threshold animal models in Anglonubian goats. Methods: Data were obtained from Anglonubian goats reared in the Brazilian Mid-North region. The traits in study were body condition score, marbling in the rib eye, ribeye area, fat thickness of the sternum, hip height, leg perimeter, and body weight. The numerator relationship matrix contained information from 793 animals. The single- and two-trait analyses were performed to estimate (co) variance components and genetic parameters via linear and threshold animal models. For estimation of genetic parameters, chains with 2 and 4 million cycles were tested. An 1,000,000-cycle initial burn-in was considered with values taken every 250 cycles, in a total of 4,000 samples. Convergence was monitored by Geweke criteria and Monte Carlo error chain. Results: Threshold model best fits categorical data since it is more efficient to detect genetic variability. In two-trait analysis the contribution of the increase in information and the correlations between traits contributed to increase the estimated values for (co) variance components and heritability, in comparison to single-trait analysis. Heritability estimates for the study traits were from low to moderate magnitude. Conclusion: Direct selection of the continuous distribution of traits such as thickness sternal fat and hip height allows obtaining the indirect selection for marbling of ribeye.