• Korean Journal of Remote Sensing
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• v.36 no.5_1
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• pp.749-762
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• 2020

Precipitation is closely related to various hydrometeorological phenomena, such as runoff and evapotranspiration. In Korean Peninsula, observing rainfall intensity using weather radar and rain gauge network is dominating due to their accurate, intuitive and precise detecting power. However,since these methods are not suitable at ungauged regions, rainfall detection using satellite is required. Satellite-based rainfall data has coarse spatial resolution (10 km, 25 km), and has a limited range of usage due to its reliability of data. The aim of this study is to obtain finer scale precipitation. Especially, to make the applicability of satellite higher at ungauged regions, 10 km satellite-based rainfall data was downscaled to 1 km data using MODerate Resolution Imaging Spectroradiometer (MODIS) based cloud property. Downscaled precipitation was verified in urban region, which has complex topographical and environmental characteristics. Correlation coefficient was similar in summer (+0), decreased in spring (-0.08) and autumn (-0.01), and increased in winter (+0.04) season compared to Global Precipitation Measurement (GPM) based precipitation. Downscaling without calibration using in situ data could be useful in areas where rain gauge system is not sufficient or ground observations are rarely available.

• The Journal of Engineering Geology
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• v.20 no.4
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• pp.381-390
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• 2010

This study assessed the hydrogeological characteristics of a seepage area of white leachate. The geological characteristics of the leachate were determined by a surface survey, and an electrical resistivity survey and borehole image processing system (BIPS) were applied to estimate the distribution of discontinuities, to assess the geological structure of the seepage areas. Fluctuations in groundwater level within boreholes were measured during periods of precipitation in the dry and wet seasons. The results show that electrical resistivity is lower in the seepage section than in non-seepage sections. The distribution of fracture zones and limestone cavities was inferred from the logging data and BIPS data. Variations in groundwater level and groundwater recharge, related to rainfall events, show the direct effect of rainfall events during the rainy season. We obtained a strong relationship between seepage amount and rainfall (correlation coefficients of 0.83-0.97).

• 한국방재학회:학술대회논문집
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• 2011.02a
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• pp.101-101
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• 2011

현재 국내에서 시행되고 있는 '4대강 살리기 사업'은 하천에서 발생하는 홍수 및 가뭄재해방지를 위한 다양한 공학적 노력을 시도하고 있다. 특히 안정적인 수위 및 유량확보와 홍수방지를 위한 보(weir)가 4대강 유역에 16개 설치되고 있다. 이러한 보 구간에는 고정보와 가동보가 복합적으로 설치되고 있으며 가동보는 그 형상과 운영방식에 따라 다양한 설계방안이 적용되었다. '4대강 살리기 사업' 중 낙동강 23공구의 강정보 공사 구간에는 원호형태의 측면 형상을 갖는 라이징 섹터게이트(Rising sector gate)가 적용되었다. 라이징 섹터게이트는 구조물의 높이가 낮고 수문의 개폐장치가 수문피어 구조물 내에 설치되어 경관이 우수하며, 구조가 간단하여 비체와 수류의 안정성이 뛰어나기 때문에 4개의 공사구간에 적용되었다. 따라서 본 연구에서는 강정보의 가동보 구간 2문 중 1문을 1/100 축척으로 제작하여 가변경사 개수로에 설치하고, 홍수 빈도별 상류 유량 조건과 하류단 수위조건으로 케이스를 정하여 실험을 수행하였다. 본 실험에서 사용한 개수로 장치는 너비 0.6 m, 높이 0.8 m, 그리고 길이 15.0 m(측정가능 구간, 헤드탱크와 테일게이트 부제외)의 개수로 실험장치이다. 측부는 모두 강화유리로 되어 육안관찰 및 계측 시 용이하게 제작되었으며, 순환식 유량 공급장치를 구축하여 수로의 하부에 설치된 유량탱크로부터 계속적으로 순환하도록 설계되었다. 또한 수로 하단으로부터 상단방향으로 약 33 m 지점에 전동 유압식 Jack screw 2기가 설치되어 경사도를 조절할 수 있도록 제작되었다. 유량조절용 판넬의 제어기판에는 디지털 경사계가 설치되어 있기 때문에 보다 정확한 경사도의 조절이 가능하다. 보 모형의 총연장은 53 cm이며 폭은 45 cm이다. 섹터게이트의 게이트부분은 직경 15 cm로 설계하였다. 문주부분을 포함한 모든 모형은 아크릴로 제작하며 레이저의 주사를 방해하지 않으며 투과율을 최대로 할 수 있도록 고강도의 아크릴을 가장 얇게 하여 중공형태를 채택하였다. 실험조건은 우선 보의 운영방안에 따라 게이트의 4가지 개방도를 설정하였고, 특히 평수위조건에서는 보의 상류부에 퇴적된 퇴적물의 세척을 위한 flushing 운영개방도 포함되어 있다. 홍수시에 대한 유량조건은 2년 빈도에 해당하는 유량을 수문의 비율과 상사법칙에 따라 설정하였으며 하류단 수위조건도 동일한 조건에 대한 값을 채택하여 적용하였다. 유동장의 해석을 위해서는 비접촉식 계측방법인 PIV(Particle Image Velocimetry) 시스템을 채택하여 2차원(x-z 방향) laser sheet를 생성하고 주입된 particle에서 반사된 변위(displacement) 정보를 상호상관(cross-correlation)기법으로 유동장을 계산하였다. 또한 수리모형과 동일한 지형격자를 구축하여 3차원 CFD 프로그램인 FLOW-3D로 계산하여 결과를 비교하였다. 특히 flushing 운영방안에 대한 게이트부의 개방도를 세가지(30, 45, $60^{\circ}$)로 구분하여 모의하였고, 적절한 개방도를 제안하고자 하였다. 실험결과는 우선 4가지 운영방안에 대한 가동보 주변에서의 유속장을 파악하였고, 최대유속의 발생위치의 변화를 확인할 수 있었다. 그리고 이에 따른 보의 바닥에서 최대유속이 발생할 경우, 하상보호공 위치와 거리 등에 대해서 분석하였다. 이를 통해 가동보 운영에 따른 다양한 유속구조를 파악할 수 있게 되며 구조적 안정성 확보를 위한 검증자료로 활용될 수 있을 것으로 예상된다. 향후, 가동보 운영방안 중 수세효과(flushing effect)에 대한 효과분석을 위해 게이트부 상류구간에 적절한 입경과 비중의 퇴적물질을 설치하는 연구와 상류부에서의 유입유사농도 및 시간변화에 따른 퇴적에 관한 연구를 수행할 계획이다.

• Korean Journal of Clinical Laboratory Science
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• v.43 no.4
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• pp.194-204
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• 2011

This study was carried out to compare the histopathological differences of liver lesions in carbon tetrachloride ($CCI_4$), dimethylnitrosamine (DMN), thioacetamide (TAA) and bile duct ligation (BDL)-induced rats. $CCl_4$, DMN and TAA were administered intraperitoneally and conducted bile duct ligation for 4 weeks to induce hepatic fibrosis. Indices of liver cell injury (steatosis, hydropic degeneration, bile duct hyperplasia, hemorrhage & hemosiderin deposition), the extent of liver fibrosis (fibrotic area) and the rate of regeneration (number of PCNA-positive cells) were investigated in each group. Liver tissues were stained with hematoxylin-eosin (HE), sirius red, prussian blue and immunostained with ${\alpha}$-smooth muscle actin (${\alpha}$-SMA), transforming growth factor-${\beta}1$ (TGF-${\beta}1$), proliferative cell nuclear antigen (PCNA), and quantified using a computerized image analysis system. Liver cell steatosis was significantly increased in $CCl_4$ and TAA groups, and hydropic degeneration and bile duct hyperplasia were significantly increased in TAA and BDL groups when compared with that in normal control, respectively. Fibrosis area was significantly increased in all four groups, especially in $CCl_4$ group. Correlation between ${\alpha}$-SMA and TGF-${\beta}1$ expressions in four groups was good. Hemorrhage area in liver parenchyma was significantly increased in DMN group only when compared with that in normal control, while hemosiderin deposition area was significantly increased in TAA and BDL groups as well as DMN group. The Number of PCNA-positive cells was significantly increased in all four groups, especially in TAA group. These results indicate that the duration and methods of hepatotoxic drug treatment are very important factors to make plans for animal experimentation on the induction of hepatic fibrogenesis in rats.

• Journal of KIISE:Software and Applications
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• v.34 no.12
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• pp.1045-1055
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• 2007

Latent topic models are statistical models which automatically captures salient patterns or correlation among features underlying a data collection in a probabilistic way. They are gaining an increased popularity as an effective tool in the application of automatic semantic feature extraction from text corpus, multimedia data analysis including image data, and bioinformatics. Among the important issues for the effectiveness in the application of latent topic models to the massive data set is the efficient learning of the model. The paper proposes an accelerated learning technique for PLSA model, one of the popular latent topic models, by an incremental EM algorithm instead of conventional EM algorithm. The incremental EM algorithm can be characterized by the employment of a series of partial E-steps that are performed on the corresponding subsets of the entire data collection, unlike in the conventional EM algorithm where one batch E-step is done for the whole data set. By the replacement of a single batch E-M step with a series of partial E-steps and M-steps, the inference result for the previous data subset can be directly reflected to the next inference process, which can enhance the learning speed for the entire data set. The algorithm is advantageous also in that it is guaranteed to converge to a local maximum solution and can be easily implemented just with slight modification of the existing algorithm based on the conventional EM. We present the basic application of the incremental EM algorithm to the learning of PLSA and empirically evaluate the acceleration performance with several possible data partitioning methods for the practical application. The experimental results on a real-world news data set show that the proposed approach can accomplish a meaningful enhancement of the convergence rate in the learning of latent topic model. Additionally, we present an interesting result which supports a possible synergistic effect of the combination of incremental EM algorithm with parallel computing.

• Journal of Yeungnam Medical Science
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• v.4 no.1
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• pp.105-121
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• 1987

The authors studied anxiety-depression using New Anxiety-Depression Scale(NADS), in the subjects of 3,499male and 1,335 female college freshmen of Yeungnam University. The authors collected the reports of NADS during the periods from January to February, 1986, and applied ANOVA and t-test on anxiety-depression scores in order to compare them between various psychosocial factors, and sexs. The results are as follows : There was significant difference in the mean awerages of total scores between male and female students: male students scored $31.49{\pm}6.57$ female students scored $33.37{\pm}6.84$ (P<0.001) The anxiety-depression scores relating to the items of sleep disturbance, apprehension, decreased libido and fatigue were relatively higher in both groups. Ninety-nine male students(2.8%) showed seriously high degree anxiety-depression scores of 50 or higher, while forty female students(3.0%) showed the same scores. There was a strong tendency toward higher anxiety-depression scores in the students who were dissatisfied with their home atmosphere, colleges, departments and familiarity of parents, and those who had pessimistic views of self image in the past, present, or fartare in both groups (P<0.001) The students whose maturation locations were below city level, showed higher level of anxiety-depression scores in both groups (P<0.05) NADS and SAS, SDS, and Leeds scale were correlated significantly in 0.64, 0.61, and 0.77 of correlation coefficient.

• Cartoon and Animation Studies
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• s.19
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• pp.161-181
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• 2010

Human beings experience the outside world through senses and have developed various ways of representation to preserve what they've experienced. The rapid progress of digital technology has opened a new era of representation technology, and furthermore, is functioning as a technology which offers new experiences. The sensory experiences through the sense of sight, which humans depend on more than 70% to perceive the outside world, have been becoming the center of representing the reality as the 3-D graphics technology has been growing, and developing by being grafted onto different areas of study. Various technologies to express the sense of reality, such as the technology to reinforce the virtual reality and to represent it in the reality, computer graphic, TUI technology, and five sensory technologies which apply humans' senses, are making advancement based on humans' visual features and sensory elements. In particular, the 3-D technology to display solidness provides not only representation but also new sensory experiences, and is emerging as the key technology to image contents. However, compared to the development of technology of 3-D graphics, there have been few basic studies on the principles of the sense of vision. Therefore, in this study, the principles and elements to sense videos will be examined. The sensory features of 3-D images to represent the sense of reality will be researched into, especially focusing on the experiential and physiological elements to sense 3-D structures, and the physical and psychological elements to sense shapes, which might be hopefully the basic study for producing 3-D contents.

• Journal of Distribution Research
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• v.6 no.2
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• pp.19-40
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• 2002

According to the secondary data, private brand(PB)'s share of retail sales is 25-30% in the USA, but about 45 in Korea. In Korea PB's average price is 23.3% less than manufacturer brand. It is very interest that PB's price advantage doesn't have a good effect on it's share of retail sales. This research's objective is to study why Korean consumers don't purchase private brand cheaper than manufacturer brand. A theoretical reasoning depends on information cue theory and means-ends model of perceived value. A unit of analysis is consumers who purchase private brand at E-mart in Pusan city, one of largest discount store in Korea. Hypothesis tested by Lisrel's structural equation model and interesting results as follows: First, favorable brand image among extrinsic cues is most positively correlated with perceived quality/sacrifice and intrinsic cues is also statistically significant. This fact imply that intrinsic cues; package, logo, country of origin are very important in the adoption of private brand in Korea. Second, compared with manufacturer's brand, PB's perceived price is positively correlated with perceived quality/sacrifice. This fact imply a assimilation effect between manufacturer's brand and private brand. Finally, a correlation between perceived sacrifice and PB proneness is satistically insignificant, but perceived quality has a significant effect on its proneness. this fact imply that innovators(about 4% of potential consumer) are risk-taker.

• Journal of Distribution Science
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• v.14 no.5
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• pp.115-123
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• 2016

Purpose - Nowadays the competition between companies has been intensified in the aviation industry. It is hard to maintain successful market share in challenging managerial environment. Not long ago, a Korean major aviation company had faced social condemnation cause of managerial staff's immoral behaviors. That company suffers great losses in company brand value in terms of authenticity as an aviation company. This research tried to show the effect of brand authenticity in the aviation industry. First of all, this research tried to define the dimensions of the brand authenticities based on the former researches. This research suggested the airline brand authenticities as three kinds of dimensions. The dimensions of authenticities consist of performance aspects, symbolic aspects and moral aspects. And this research also tried to show the relationships between brand authenticities and consumers attitudes. Research design, data and methodology - The empirical research design is based on the experiments with six types of advertisement prototypes. The advertisement prototypes were based on three types of authenticities' characteristics. The prototypes were made of core statements about each authenticity. And the advertisement prototypes also were based on the aviation company types. The types of aviation companies could be divided into FSC(full service carrier)and LCC(low cost carrier). So the whole experiments were performed with six kinds of advertisement prototypes(3 brand authenticities X 2 aviation company types). The age of participants were from 20s to 40s. The proportion of participants' demographics are as follow. Age proportion is 50% of 20s and 50% of 30s and 40s. Gender proportion is 46% males and 54% females. The experiments performed through mobile devices. Advertisement prototypes were exposed to the participants through their mobile devices, and they answered the questionnaires. All the process of experiments were performed by a professional research firm to maintain the quality of data. Results - This research suggested some important outcomes as follow. First, brand authenticity had an important role to make a positive consumer attitude on the aviation company. All the three types advertisement of authenticities had a positive impact on the consumer attitude for the aviation company. Second, the three types of brand authenticities in the performance aspects, symbolic aspects, and moral aspects had a major impact on the consumers attitudes. The performance authenticity had the biggest effect on the consumer attitudes. Third, the types of aviation companies like FSC and LCC had a different correlation with types of authenticities. All the types of authenticities affected on the consumers attitudes in the FSC case. The symbolic authenticity had the biggest effect in the FSC case. But the performance authenticity showed the most striking effect in the LCC case. Conclusion - From this research, we can get a conclusion. The brand authenticity of aviation company should be managed carefully to maintain a positive brand image and consumers attitudes. And airline brand authenticities can be consist of three type dimensions. All the types of authenticities affects on the consumers attitudes positively. The symbolic authenticity affects more in the FSC case, and the performance authenticity influences more in the LCC case.

• Clinical and Experimental Pediatrics
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• v.52 no.10
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• pp.1136-1139
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• 2009

Purpose:It is critical that the exact gestational age of a newborn baby, especially premature baby, be determined to evaluate the status of a disease and its management and to estimate the prognosis of a patient. This study aimed to investigate an easy and accurate method to estimate gestational age on cranial ultrasound, requiring minimal additional time and equipment. Methods:A high-resolution coronal sonographic image was obtained via the anterior fontanel with a 5-12 Mhz linear probe after the usual cranial sonographic examination. We measured the depth of cerebral hemisphere, thickness of corpus callosum, and depth of cingulate sulcus and obtained the correlations between these factors and gestational age. Results:Depth of cingulate sulcus had the highest correlation coefficiency with gestational age (r=0.878, P=0.000). All the cases, except for 2 cases, had a gestational age of more than 37 weeks, when the depths of cingulate sulcus were more than 0.55 cm, and had a gestational age less than 34 weeks, when the depths of cingulate sulcus were less than 0.35 cm. Conclusion:Measurement of the depth of cingulate sulcus was a simple and accurate method to estimate the gestational age on cranial ultrasound. The gestational age is more than 37 weeks, when the depth of cingulate sulcus is more than 0.55 cm, and is less than 34 weeks, when the depth of cingulate sulcus is less than 0.35 cm.