• 콘크리트학회논문집
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• 제17권5호
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• pp.751-760
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• 2005

본 논문에서는 확산과 수분이동에 의한 침투를 함께 고려할 수 있는 염소이온침투 모델을 제시하고 이를 바탕으로 유한요소 프로그램을 개발한다. 개발된 프로그램을 이용하여 습도와 온도가 연속적으로 변화하는 현장상태에 대한 염소이온 침투 해석을 수행한다. 해석과정으로 먼저 수분확산해석을 수행한다. 이 해석에 의한 각 유한요소의 상대습도를 바탕으로 염소이온 침투해석을 위한 재료상수를 구한다. 이러한 재료상수를 이용하여 염소이온 침투해석을 수행하게 된다. 각 유한요소들은 시간과 재령에 따라 연속적으로 변화하는 재료상수 값을 가지게 된다. 내외부의 상대습도 차이가 크면 수분이동에 의한 염소이온 침투의 영향이 커지지만 내외부의 상대습도의 차이는 수분확산에 의해서 재령에 따라 감소하므로 수분이동에 의한 염소이온 침투의 영향은 재령에 따라 감소한다. 반복 습윤은 수분이동에 의한 염소이온 침투의 영향을 증가시켜 철근 주위의 염소이온 농도를 커지게 한다. 현장상황과 같이 건습의 반복이 장기적으로 발생하게 되면 수착과 확산을 함께 고려한 염소이온 침투량이 수분이동을 고려하지 않은 염소이온 침투량보다 매우 크다. 따라서, 항만 콘크리트 구조물에 대한 염소이온 침투해석을 장기재령동안 수행할 경우에는 수분이동 메커니즘을 포함한 수치 모델링을 바탕으로 건습의 반복을 고려하여 해석을 수행하는 것이 해석의 오차를 줄일 수 있을 것이다.

• Asian-Australasian Journal of Animal Sciences
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• 제17권6호
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• pp.760-768
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• 2004

The present study was undertaken to evaluate the accuracy of ultrasonography in early pregnancy diagnosis in goats. Ultrasonographic scanning with real time B-mode ultrasound machine having 5 MHz linear array transducer was performed on gravid uterus (n=24) obtained from slaughterhouse (Group I). Crown rump length (CRL) measured by ultrasound was found significantly different (p<0.05) with actual CRL measured after dissection in early pregnancy. However, age predicted by ultrasound through the measurement of CRL was found highly correlated (r=0.92) with age measured after dissection through CRL and the weight of fetus. Ages predicted by ultrasound through the measurement of trunk diameter (TD) and uterine diameter (UD) and ages measured after dissection were found highly and equally correlated (r=0.98) and did not differ significantly. Data from six does synchronized (Group II) with PGF2$\alpha$ (Estrumate) at 11 days apart were collected through ultrasound from 17 to 42 days post breding. The correlation between CRL and gestational age was high (r=0.97) in day 30 to 42 post breeding. A high coefficient of correlation (r=0.98) was also observed between predicated age by ultrasound and actual age calculated after kidding. The correlation between CRL and gestational age by the formula Y=(a+bX) i.e. Y=24.42+0.39 X where Y=gestational age and X=CRL, was recorded very high (r=0.99). Accuracy of ultrasonography was lowest on day 17 to 19 (66%) and reached 100% on day 34. Data from 30 does (group III) randomly subjected to only one time ultrasounds scanning to assess the accuracy of pregnancy diagnosis were also obtained. Ages predicted by TD and UD measurements were observed to be non-significantly different with actual age obtained after kidding and correlation between ages predicted by TD and UD measurement with actual age after kidding was found equally and highly correlated (r=0.98). The operator's accuracy in the whole experiment including all three groups was found to be 92%. The sensitivity was 93% and specificity was 86%. From the present study, it was observed that CRL was the most reliable parameter to find out gestational age in early pregnancy and the new formula derived was found very accurate to find out gestational age. TD and UD were also found to be equally reliable parameter to find out gestational age in mid and late stage of pregnancy through ultrasonography. It was concluded that ultrasonography by real time B mode with 5 MHz transrectal transducer was found to be reliable, safe and accurate and practicable means in diagnosing early pregnancy diagnosis as early as 25 days post breeding.

• 유통과학연구
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• 제13권5호
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• pp.83-90
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• 2015

Purpose - This research aims to understand the different behaviors of consumers according to cognitive age. Specifically, this research is focused on pro-social behavior. Pro-social behavior is defined as behavior benefiting others, rather than behavior benefiting one's self. It often entails individual risk or cost, such as when giving resources to others, waiting in line, asking for or paying a fair price, or risking one's life in battle. Therefore, we sought to understand consumer psychology and cognitive age as a reflection of inner psychology. People frequently perceive themselves as younger or older than their chronological ages. This self-perceived or cognitive age is a subjective age perception independent of actual chronological age. The discrepancy degree between chronological and cognitive age represents how much individuals perceive themselves as younger than they are. This study examines the gap in donation intention based on cognitive age. In order to investigate cognitive age, composed of four sub-categories (feel-age, look-age, do-age, and interest-age), this study explores the differential donation intention based on cognitive age, which determines the relationship between the young age and old age. Research design, data, and methodology - Data research was conducted by gathering 216 survey samples, excluding those with unreliable answers. Data coding and cleaning were used and SPSS 19.0 software for the data analysis. The respondents were categorized into two types, younger cognitive ages and older cognitive ages. Additionally, we analyzed the moderating variables. In particular, we used cognitive age degree and congruency level (cognitive age low vs. cognitive age high) × (congruency close vs. congruency distant) between - subjects design. First, regression was done to verify the difference between chronological age and cognitive age. Second, a t-test was done to verify the difference of cognitive age level in donations. Third, ANOVA (analysis of variance) was done to verify the difference between cognitive age and congruency in donations. Last, ANOVA was done to verify the difference between cognitive age and moral judgments in donations. Result - The results show most respondents perceive themselves as younger than their chronological ages. In particular, older respondents feel they are younger than their actual age. Moreover, the result of the comparison between low degree and high degree groups of cognitive age, show high donations at the higher degree of cognitive age groups. In addition, the closer the distance to the beneficiaries, the higher the donation in high degree cognitive age groups. The higher moral judgment groups also show relatively high contributions in lower degree cognitive age groups. Conclusions - Donations belong to the category of pro-social behavior reflecting an individual's psychological state. Therefore, it is important in understanding cognitive age. This study implies that it is necessary to take into account both cognitive age and chronological age when segmenting donors. Moreover, this study confirmed that there are different factors affecting the motives behind donations. Thus, it may be utilized to create differential donation strategies.

• 대한화장품학회지
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• 제39권3호
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• pp.233-239
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• 2013

본 연구에서는 연령별 수분함유량, 유분함유량 및 경표피수분함유량에 대한 데이터를 비교 분석함으로써 연령별 피부 특성 차이를 규명하여 향후 화장품 산업개발에 도움을 줄 수 있는 기초자료를 제공하고자 한다. 피험자 남녀 총 638명을 대상으로 볼 부위의 수분함유량, 코 끝 부위의 유분함유량, 볼과 전박부위의 경표피수 분손실량을 측정하였으며, Statistical Package for the Social Sciences (version 19.00; SPSS Inc., Chicago, IL, USA) 프로그램을 사용하여 분석하였고 피험자에 대한 정보뿐 아니라 피부 수분함유량, 유분함유량, 경표피수분손실량의 피부 측정치 결과를 평균 ${\pm}$ 표준편차로 나타내었다. 그 결과 볼 부위의 수분함유량은 여성이 남성보다 높았으며, 연령이 높아질수록 수분함유량이 증가하였다. 또한 코 부위의 유분함유량은 남성이 여성보다 높았으며 연령이 낮아질수록 유분함유량이 증가하였다. 볼 부위의 경표피손실량은 여성이 남성보다 높은 반면, 전박 부위의 경표피손실량은 남성이 여성보다 높았다. 이상의 연구 결과로 추후 화장품 산업에서 연령별, 성별 기초화장품 개발 등에 도움을 줄 수 있는 기초자료로 활용될 수 있을 것이라 사료된다.

• 분석과학
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• 제22권1호
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• pp.51-56
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• 2009

천리포 해안사구 퇴적층에 대한 연대측정을 Optically Stimulated Luminescence (OSL)을 이용하여 Single Aliquot Regeneration (SAR) 법 중 열처리 조건을 일부 수정하여 실시하였다. 예열과 cut-heat을 각각 $260^{\circ}C$ 10 초 $-220^{\circ}C$ 0 초와 $270^{\circ}C$ 10 초 $-270^{\circ}C$ 10 초의 두 가지 조합을 적용하였다. 예열 및 cutheat의 열처리 과정을 변화시킴으로써 원하는 신호만을 선별하는 것이 가능했으며, 이를 등가선량을 구하는데 이용하였다. 또한 시료를 $75{\mu}m$, $150{\mu}m$, $200{\mu}m$의 표준체로 크기를 4개의 영역으로 구분하였고, 열처리 조건의 변화와 입자의 크기가 달라짐에 따라 등가선량이 다르게 측정되어 다른 연대가 산출되었다. 그 결과는 방사성탄소연대측정법에 의한 연대와 비교하였다. 입자의 크기에 따라 다른 연대가 산출된 것으로 미루어 천리포 해안사구 퇴적지층은 토양의 유입원이 혼합되어 구성되었음을 추정할 수 있었다.

• Journal of Ginseng Research
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• 제32권3호
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• pp.194-209
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• 2008

연구 결과는 아래와 같다. 풍화토양의 경우 대부분 원소가 셰일 지역이 낮고, 천매암 및 화강암 지역에서 높았다. 상관계수에서 화강암 지역이 더욱 많은 원소에서 정 및 부의 상관관계를 보였다. 밭토양의 경우 천매암 및 화강암 지역이 높았고, 셰일 지역은 낮았다. 연생별 비교에서 셰일 지역의 4년, 천매암 지역의 2년, 화강암 지역의 3년생 토양이 높았다. 연생이 증가함에 따라 정의 상관관계가 증가하였다. 동일 연령이라도 셰일 지역에 비해 천매암 지역이 정의 상관관계가 증가하였다. 인삼의 경우 평균값에서 높은 원소 및 낮은 원소 함량이 화강암 지역에서 나타났다. 연생별 원소 함량에서 2, 3년생이 낮고, 4년생이 높은 원소가 많았다. 셰일 지역은 2, 4년생이, 천매암 및 화강암 지역은 4년생에서 높았다. 상관계수에서 2, 4년생은 정의 상관관계가 셰일 지역이 우세하였고, 3년생의 경우는 화강암 지역이 우세하였다. 평균값의 경우 화강암 지역이 우세하였고, 셰일 지역이 약하였다. 암상에 관계없이 평균값을 포함한 3 지역 모두, Al-Ti 쌍에서 정의 상관관계를 보였다. 타 지역 동일 연생별 성분 비교에서 화강암 지역은 연생이 증가함에 따라 높은 함량의 원소가 많았다. 상대 비에서 2년생은 화강암 지역이, 3년생과 4년생에는 셰일 및 지역이 천매암 지역이 높은 함량을 보였다. 풍화토와 밭토양의 관계에서 전체 풍화토가 화강암 지역 쪽에서 높음을 암시한다. 셰일 지역에서 천매암, 화강암 지역으로 갈수록 1 이상을 보이는 원소가 많아 셰일 지역에 비해 화강암 지역에서 풍화토가 높았다. 토양과 인삼의 성분과의 관계에서 연생에 관계없이 3 지역 공히 평균값에서 전 원소가 인삼보다 토양이 높음을 암시하고, 연생에 관계없이 인삼보다 토양이 Al, Ti는 수 백 배 이상, Mn은 수 십 배 이상 높았다. 동 지역내 연생 차이별 비교(밭토양/인삼 함량)에서 지역별 원소 별 차이가 있었으나 공히 밭토양이 인삼보다 Al, Ti는 수 백 배, Mn은 수 십 배 차이를 보였다. 타 지역 동일 연생 별 비교에서 2, 3, 4년 공히 높은 비율이 셰일 지역의 Na, 천매암 지역의 Mn, 낮은 비율이 셰일지역의 Mg, 화강암 지역의 Al, Mn, Na에서 나타났다. 즉 토양과 인삼 성분 차이가 셰일 지역의 Na, 천매암 지역의 Mn에서 크고, 셰일 지역의 Mg, 화강암 지역의 Al, Mn, Na 에서 작았다.

• 치과방사선
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• 제6권1호
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• pp.51-58
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• 1976

The study was performed to investigate the thickness of lamina dura of the human teeth in normal condition, which obtained from the intraoral roentgenograms of the 1200 cases taken by bisecting technique. All films were divided into the different ages, the different sexes, and the different location of the different teeth. The obtained results were as follows: 1. With advancing age in both sexes, the lamina dura tends to become thinner as following. (equation omitted) 2. Generally, the alveolar crest is the thickest among the root surfaces, and apex, midroot followed, and the average thickness of the posterior teeth is thicker than that of the anterior teeth. 3. The mean value of the whole maxillary teeth is larger than the one of the whole mandibular teeth. 4. On the whole cases, the differences of male and female is about 0.019㎜, which is not a significant differences.

• Asian-Australasian Journal of Animal Sciences
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• 제27권2호
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• pp.155-160
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• 2014

The purpose of this study was to estimate genetic parameters of ultrasound measurements for longissimus dorsi muscle area (LMA), backfat thickness (BFT), and marbling score (MS) in Hanwoo cows (N = 3,062) at the ages between 18 and 42 months. Data were collected from 100 Hanwoo breeding farms in Gyeongbuk province, Korea, in 2007 and 2008. The cows were classified into four different age groups, i.e. 18 to 22 months (the first pregnancy period), 23 to 27 (the first parturition), 28 to 32 (the second pregnancy), and 33 to 42 (the second parturition), respectively. For each age group, a multi-trait animal model was used to estimate variance components and heritabilities of the three traits. The averages of LMA, BFT, and MS measurements across the cows of all age groups were 50.1 $cm^2$, 4.62 mm, and 3.04, respectively and heritability estimates were 0.09, 0.10, and 0.08 for the respective traits. However, when the data were analyzed in different age groups, heritability estimates of LMA and BFT were 0.24 and 0.47, respectively, for the cows of 18 to 22 months of age, and 0.21 for MS in the 28 to 32 months old cows. When the cows of all age groups were used, the estimates of genetic (phenotypic) correlations were 0.43 (0.35), -0.06 (0.34) and 0.21 (0.32) between LMA and BFT, LMA and MS, and BFT and MS, respectively. However, in the cow age group between 28 and 32 (18 and 22) months, the estimates of genetic (phenotypic) correlations were 0.05 (0.29), -0.15 (0.24) and 0.38 (0.24), for the respective pairs of traits. These results suggest that genetic, environmental, and phenotypic variations differ depending on cow age, such that care must be taken when ultrasound measurements are applied to selection of cows for meat quality.

• Asian-Australasian Journal of Animal Sciences
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• 제19권4호
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• pp.605-610
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• 2006

The objective of the present experiment was to determine the effects of slaughtering at different ages and the use of a commercial probiotic (115-Biogallinox) in broiler diets on the color properties of carcasses, during the first 24 h following slaughter. Ross 308 male broiler chickens obtained from a commercial hatchery were raised to either 35 or 42 days of age. Chickens were fed with different levels of probiotic ($P_0$: 0.0%, $P_1$: 0.1% and $P_2$: 0.2%) containing Saccharomyces cerevisiae during the experimental period. At the end of the trial all birds were slaughtered and then stored at $3^{\circ}C$ for 24 h. The pH and skin colour of carcasses were determined 1, 3, 7, 10, 13, 17 and 24 h after slaughter. Although the use of probiotic and post-mortem ageing time affected the pH (p<0.01), it was not affected by slaughter age (35 and 42 days) (p>0.05). The highest pH values occurred in carcasses of broilers fed 0.2% probiotic. The pH values of carcasses decreased with post-mortem ageing time (p<0.01). Main factors (treatment, slaughter age and post-mortem ageing time) had an effect on colour ($L^*$, $a^*$ and $b^*$) values (p<0.01). $L^*$ values of 42d-old slaughter and $P_2$ group were lower than those of 35d-old slaughter and other probiotic groups. The $a^*$ and $b^*$ values of 35d-old slaughter were lower than those of 42d-old slauhgter. The $a^*$ and $b^*$ values increased during post-mortem ageing (p<0.01). It was determined that changing of the colour traits of broiler carcasses was correlated with probiotic, pH and post-mortem ageing time. Also, it was observed that darkness of carcass colour increased as time progressed.

• Imaging Science in Dentistry
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• 제53권2호
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• pp.153-159
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• 2023

Purpose: The objective of this study was to assess the fractal dimension, lacunarity, trabecular microarchitecture parameters, and cortical linear measurements in the mandibles of male and female individuals to identify differences between them. Materials and Methods: In total, 116 cone-beam computed tomography scans of healthy individuals of different ages (57 men and 59 women, aged between 20 and 60 years) were selected. The following bone parameters were measured: 1) buccal, lingual, and basal cortical bone thickness in 5 standard parasagittal sections (the midline, the left and right sides of the lower lateral incisors, and the left and right sides of the lower canines); 2) the bone volume fraction of 10 sequential axial sections from each patient by creating a volume of interest in the area between the lower canines; and 3) fractal dimension and lacunarity using grayscale images of the same region of the volume of interest in the anterior mandible. Spearman correlation coefficients and the Mann-Whitney test were used. Results: A significant and positive correlation was found between age and cortical thickness, especially in the region of the central incisors. Significant differences between sexes in terms of fractal dimension, lacunarity, and bone volume were found. Women revealed lower fractal dimension values and higher lacunarity and bone volume ratio values than men. Conclusion: Fractal dimension, lacunarity, trabecular bone volume, and cortical thickness were different between men and women of different ages.