• Journal of Ocean Engineering and Technology
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• v.27 no.6
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• pp.32-42
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• 2013

In this paper, a wave-induced swirl water chamber (SWC) for breakwater and wave power generation is introduced and its applicability to wave power generation in the coastal waters of Korea is investigated. The SWC type of wave power generation is a way to drive a turbine using the unidirectional swirl flow that is induced in the back of a curtain wall of a breakwater due to incident waves. The typical wave characteristics are obtained by analyzing the annual statistical wave data from KHOA (Korea Hydrographic and Oceanographic Administration). A numerical analysis is carried out on the variations in the SWC entrance height, wave height, and different installation conditions. For the numerical analysis, a commercial code, Fluent based on FVM, is used. As the entrance height decreases, the mass flow rate through the entrance is rarely changed, whereas the magnitude of the flow velocity of the smaller entrance height is greater than the other ones, which is better for the formation of an SWC swirl flow inside and the flow kinetic energy at the entrance. In cases of installation conditions where a wall is place behind and under SWC, it has been shown that the mass flow rate through the entrance is greater than that in the open condition, and sufficient flow kinetic energy is generated in the entrance for wave power generation. However, the swirl flow kinetic energy is relatively small. Thus, in the future, it is necessary to study the swirl flow generation, which is affected by the SWC shape.

• Journal of the Korean Solar Energy Society
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• v.36 no.1
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• pp.11-18
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• 2016

The local wind systems in the Pohang region were categorized into wind sectors. Still, thorough knowledge of wind resource assessment, wind environment analysis, and atmospheric environmental impact assessment was required since the region has outstanding wind resources, it is located on the path of typhoon, and it has large-scale atmospheric pollution sources. To overcome the resolution limitation of meteorological dataset and problems of categorization criteria of the preceding studies, the high-resolution wind resource map of the Korea Institute of Energy Research was used as time-series meteorological data; the 2-step method of determining the clustering coefficient through hierarchical clustering analysis and subsequently categorizing the wind sectors through non-hierarchical K-means clustering analysis was adopted. The similarity of normalized time-series wind vector was proposed as the Euclidean distance. The meteor-statistical characteristics of the mean vector wind distribution and meteorological variables of each wind sector were compared. The comparison confirmed significant differences among wind sectors according to the terrain elevation, mean wind speed, Weibull shape parameter, etc.

• Journal of Applied Biological Chemistry
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• v.66
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• pp.484-491
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• 2023

Maize is one of the major crops consumed in worldwide, which nutrients accounts for a large amount of starch, but also functional components, and phenolic acid is known to have a high content. Maize is divided into waxy maize, sweet maize, and normal maize with its shape and use, therefore there is also a difference in nutritional composition. This study was conducted to analyze the content of functional components according to the type of maize and to produce natural variation data in consideration of environmental factors. 3 shapes of maize (waxy maize, sweet maize, and normal maize) samples cultivated in 3 regions (Suwon, Daegu, and Hongcheon) were analyzed using HPLC and GC-TOF-MS. Comparing with type through ANOVA, multivariate statistical analysis, Pearson correlation analysis, 28 components, including carotenoids and tocopherols, showed significant differences among a total of 32 components (p <0.05), 15 of them showed very significant differences (p <0.001). When comparing with regions, 15 components showed significant differences and only vanillate, syringate, C23-ol of them showed most significant differences (p <0.001). As a result of principal component analysis, cluster classification was distinguished by shape than by region, with α-carotene, cholesterol for waxy maize, vanillate and stigmasterol for sweet maize, lutein and β-carotene for normal maize had a great effect on cluster formation. It suggests that the content of functional components is more affected by genetic factors than environmental factors.

• Journal of architectural history
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• v.5 no.2 s.10
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• pp.25-39
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• 1996

Architectural researches on the traditional houses of Korea have been studied mainly based on the data collected in the field survey. From explosively incresed real mesurements and drawings in the field, plenty of data have been collected. Those have been the basic data for verifing and developing the theories on the traditional house. But after Korean war the researchers in South-Korea were not able to approach to the field in North Korea, so the new data of North Korea were not added any more. The poverty of real data have caused regional unbalance in the researches. This paper aims at collecting new data of traditional house in North Korea. But still being prohibited for the researchers of South Korea to approach to the field, I had to depend on the memories and experiences of the immigrants from North Korea who are now living in Kyon-Nam and Pusan Province. Through the questionnaire and drawings, they described vivid memory of their old houses. I was able to collect the data of 71 cases, which are significant and valuable as much as those of the real field are. The data include the address and site condition, family structure, economic condition, construction period of each house, The drawings by themselves show the building forms and plans, the plans of each building, and the included spaces. Although the quantity of those data is not enough for statistical analysis, it shows general tendency for analizing regional charateristics, the differnces among economical classes, and the periodical change. It opens the way for verfying the existing theory. Analizing the data, I have some conclusions as followings: a. Most of researchers have classified the dominant housing type of Hamkyong-Do as 'the double fold' type. In this study, all cases of Hamkyongbuk-do also show 'the double fold plan with Chongju-kan'. But in Hamkyongnam-do some cases show 'the double fold plan without Chongju-kan, or projecting the stable into the yard, which seem to be different type from 'the double fold plan with Chongju-kan' b. Existing theories classified the dominant housing type of Pyongahn-do as 'two buildings with pararell arrangement'. This classification is verified with the plentiful cases in this study. Futhermore, I found new tendency, that is, getting higher econnomic condition, they construct annex buildings between the main buildings. Finally their houses show 'scattered ㅁ shape'. The houses included in this two types has narrow and closed inner yard, which is different from the houses of the same shape in the south region of Korea. c. Existing theories classified the dominant housing type of Hwanghae-do as 'ㅁ sape with Daechong' type. I found many cases of 'ㅁ shape', but only two cases show 'Daechong'. 'The doble fold' type was also founded. Unfortunately very few cases were sent from Hwanghae-do, it is not enough for finding general tendency.

• Convergence Security Journal
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• v.19 no.2
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• pp.91-104
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• 2019

In this paper, we present a novel local descriptor, Local Prominent Directional Pattern (LPDP), to represent the description of facial images for gender recognition purpose. To achieve a clearly discriminative representation of local shape, presented method encodes a target pixel with the prominent directional variations in local structure from an analysis of statistics encompassed in the histogram of such directional variations. Use of the statistical information comes from the observation that a local neighboring region, having an edge going through it, demonstrate similar gradient directions, and hence, the prominent accumulations, accumulated from such gradient directions provide a solid base to represent the shape of that local structure. Unlike the sole use of gradient direction of a target pixel in existing methods, our coding scheme selects prominent edge directions accumulated from more samples (e.g., surrounding neighboring pixels), which, in turn, minimizes the effect of noise by suppressing the noisy accumulations of single or fewer samples. In this way, the presented encoding strategy provides the more discriminative shape of local structures while ensuring robustness to subtle changes such as local noise. We conduct extensive experiments on gender recognition datasets containing a wide range of challenges such as illumination, expression, age, and pose variations as well as sketch images, and observe the better performance of LPDP descriptor against existing local descriptors.

• Journal of the Korean Arthroscopy Society
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• v.13 no.1
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• pp.34-38
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• 2009

Purpose: To evaluate the association of subacromial bursa inflammation with acromial shape and shoulder pain in subacromial impingement syndrome. Materials and Methods: 24 cases with subacromial impingement syndrome were reviewed. Eighteen patines were males and six females(mean age: 58.3 yrs). During arthroscopic operation, the specimens were taken from subacromial bursa with arthroscopic knife($1{\times}1$ cm size). The shape of acromion were classified according to Bigliani grading system. The shoulder pain of patients was graded with visual analog scale (VAS). The grade of inflammation was classified to the pathological three grade system (mild, moderate, severe) by pathohistological 8 factors. Results: Of total 24 cases, 9 cases were the pathological grade I and 15 cases were grade II. None was grade III. In the 9 cases of pathological grade I, 6 cases were the radiologic grade II of acromial shape and 3 cases were grade III. In the 15 cases of pathological grade II, 5 cases were the radiologic grade II and 10 cases were grade III. The VAS was 7 point at pathological grade I and 8 point at grade II. As the statistical analysis, the pathological grade of subacromial bursa was associated with acromial shape (p<0.05), but not associated with pain of patient (p>0.05). Conclusion: Our study suggests that pathological grade of subacromial bursa inflammation was associated with acromial shape. But pathological grade of subacromial bursa inflammation was not associated with shoulder pain of patients.

• Fashion & Textile Research Journal
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• v.7 no.2
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• pp.187-195
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• 2005

The purposes of this study were to investigate the effects of the elements of textile design on consumer emotion and to develop the emotion model which is suitable for the textile design. The descriptive system of textile design was developed based on the previous studies. Emotion measurement scale was developed to analyze the consumer emotion for the textile design. 20 representative types of textile design were collected as stimuli set for this study, consumer emotion on each design type was examined and was analyzed through the survey. For the data analysis, principal component analysis was employed. As a result, 8 emotional factors such as 'Modern', 'Fun', 'Natural', 'Elegance', 'Classic', 'Ethnic', 'Wild' and 'Sporty' were derived from the results of the survey. Emotion measurement scale which consisted of 8 factors was developed to analyze the effects of the elements of textile design on consumer emotion and 80 representative types of textile design were collected. In addition, the emotion which consumers feel for the textile design types was investigated and each textile design was described according to the descriptive system of textile design. Statistical methods of pearson correlation and multiple regression were employed to analyze the relationship between the elements of textile design and consumer emotion. The results of this study revealed that 15 design elements which affected consumer emotion were the size of motives, the shape of motives, the degree of tone contrast among motives etc. This study findings can provide specific design methods for the effectiveness of consumer emotion.

• The Research Journal of the Costume Culture
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• v.6 no.4
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• pp.26-38
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• 1998

This paper is based on a survey of consumers 'opinions on underwears. The questions in the survey dealt with what materials were used to manufacture underwears, which underwears were worn together in combinations, and how comfortable underwears were. In addition, the respondents were asked about how many pieces of different underwears they posses. Through such research, this paper aims to provide a guide to manufacturing domestic underwears that are competitive against foreign bands. 336 women in their twenties, thirties, forties and fifties from Seoul and it's suburbs were surveyed. Statistical analysis was performed by calculating the average, frequency and standard deviation, and through one-way analysis and the Duncan test. The following are the results of the study : 1. Consumers were moderately satisfied with Korean-made underwears. In order to complete with foreign brands, products with high consumer-satisfaction levels must be produced. 2. Upper garments usually consisted of brassieres with shoulder straps and sleeveless shirts. For lower underwears, most people tended to wear panties under girdle, with garlets on top. This is most likely the resut of more people wearing slacks than skirts. 3. Consumer in their twenties had anaverage of 1.71 slips, while those in their thirties had 3.07, those in their forties and 3.25, and people in their fifties had 3.88 slips. Thus the number of slips a consumer possesses increases as age increases. for socks, people in their twenties had 7.4 pairs on average, those in their thirties had 5.5, those in their forties had 6.7, and those in their fifties had 5.3. Thus, those in their twenties possessed the most number of socks. Consumers in their twenties also had the largest proportion of socks among all the types of hosiery combined, with 47.1% of their hosiery being socks. 4. Consumers did tend to prefer cotton underwears, but according to the type of underwears, producting using mixed fabrics of cotton and synthetic fibers were also frequently worn. 5. The shape and form of underwear that consumers prefer in a ceratin time frame varies according to the latest fashion in outer wear. Therefore, planning design of underwear products by predicting the future trend of outer wear fashion is necessary.

• The korean journal of orthodontics
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• v.46 no.1
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• pp.3-12
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• 2016

Objective: The purpose of this study was to compare the precision of three-dimensional (3D) images acquired using iTero$^{(R)}$(Align Technology Inc., San Jose, CA, USA) and Trios$^{(R)}$(3Shape Dental Systems, Copenhagen, Denmark) digital intraoral scanners, and to evaluate the effects of the severity of tooth irregularities and scanning sequence on precision. Methods: Dental arch models were fabricated with differing degrees of tooth irregularity and divided into 2 groups based on scanning sequence. To assess their precision, images were superimposed and an optimized superimposition algorithm was employed to measure any 3D deviation. The t-test, paired t-test, and one-way ANOVA were performed (p < 0.05) for statistical analysis. Results: The iTero$^{(R)}$ and Trios$^{(R)}$ systems showed no statistically significant difference in precision among models with differing degrees of tooth irregularity. However, there were statistically significant differences in the precision of the 2 scanners when the starting points of scanning were different. The iTero$^{(R)}$ scanner (mean deviation, $29.84{\pm}12.08{\mu}m$) proved to be less precise than the Trios$^{(R)}$ scanner ($22.17{\pm}4.47{\mu}m$). Conclusions: The precision of 3D images differed according to the degree of tooth irregularity, scanning sequence, and scanner type. However, from a clinical standpoint, both scanners were highly accurate regardless of the degree of tooth irregularity.

• The Korean Journal of Applied Statistics
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• v.33 no.2
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• pp.123-136
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• 2020

It is common to encounter correlated multiple outcomes measured on the same subject in various research fields. In developmental toxicity studies, presence of malformed pups and fetal weight are measured on the pregnant dams exposed to different levels of a toxic substance. Joint analysis of such two outcomes can result in more efficient inferences than separate models for each outcome. Most methods for joint modeling assume a normal distribution as random effects. However, in developmental toxicity studies, the response distributions may change irregularly in location and shape as the level of toxic substance changes, which may not be captured by a normal random effects model. Motivated by applications in developmental toxicity studies, we propose a Bayesian joint model for binary and continuous outcomes. In our model, we incorporate a skewed logit model for the binary outcome to allow the response distributions to have flexibly in both symmetric and asymmetric shapes on the toxic levels. We apply our proposed method to data from a developmental toxicity study of diethylhexyl phthalate.