• The Journal of Advanced Prosthodontics
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• 제11권6호
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• pp.324-330
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• 2019

PURPOSE. The aim of the study was to evaluate and compare the fracture resistance and modes of fracture of monolithic zirconia crowns with two preparation designs. MATERIALS AND METHODS. Forty human maxillary first premolar teeth were extracted for orthodontic purposes and divided into two main groups (n=20): Group A: monolithic traditional zirconia; Group B: monolithic translucent zirconia. The groups were further subdivided into two subgroups (n=10): (A1, B1) shoulder margin design; (A2, B2) feather-edge margin design. Teeth were prepared with either a 1 mm shoulder margin design or a feather-edge margin design. The prepared teeth were scanned using a digital intraoral scanner. The crowns were cemented using self-adhesive resin cement. All cemented teeth were stored in water for 7 days and thermocycling was done before testing. All samples were subjected to compressive axial loading until fracture. The fractographic analysis was done to assess the modes of fracture of the tested samples. RESULTS. The highest mean values of fracture resistance were recorded in kilo-newton and were in the order of subgroup A1 (2.903); subgroup A2 (2.3); subgroup B1 (1.854) and subgroup B2 (1.523). One-way ANOVA showed a statistically significant difference among the 4 subgroups. Concerning modes of fracture, the majority of samples in subgroups A1 and B1 were fracture of restoration and/or tooth, while in subgroups A2 and B2, the majority of samples fractured through the central fossa. CONCLUSION. Even though all the tested crowns fractured at a higher level than the maximum occlusal forces, the shoulder margin design was better than the feather-edge margin design and the monolithic traditional zirconia was better than the monolithic translucent zirconia in terms of fracture strength.

• Asian-Australasian Journal of Animal Sciences
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• 제22권6호
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• pp.796-802
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• 2009

The effects of docking on growth traits, fattening performance, carcass characteristics and blood biochemical parameters were investigated using 24 fat-tailed Sanjabi single-born male lambs raised from a large commercial sheep herd. The lambs were randomly divided into two groups. One group (n = 12) were docked at two days of age with rubber-rings using an elastrator. The second group (n = 12) were left intact. After weaning (90 days), all lambs were moved to rustic rangelands for 40 days. Then all the lambs were fed concentrates ad libitum for 60 days during the fattening period. Growth traits, body weight and average daily gain (kg) were recorded at the end of the weaning and fattening periods. Blood biochemical parameters including urea, total protein, glucose, triglycerides, cholesterol, low-density lipoproteins (LDL) and high-density lipoproteins (HDL) were measured during the fattening period. Finally, at the end of the fattening period, eight lambs (4 intact and 4 docked lambs) were slaughtered in order to determine carcass characteristics. Fat-tail docking had no effect (p>0.05) on lamb growth from birth to weaning. Body weight and average daily gain of docked lambs were significantly higher (p<0.05) than for intact lambs at the end of the fattening period. There was no difference in carcass measurements between the two groups, except for chest depth and leg weight which were higher (p<0.05) in docked lambs. During the fattening period, cholesterol and LDL of docked lambs were less than in intact lambs (p<0.05). The current results indicated that docking with rubber rings causes an improvement in growth traits during the fattening period and leads to desirable carcass characteristics compared to intact lambs; interestingly, this procedure had a significant effect on the lowering of blood cholesterol and LDL of docked lambs.

• 복식
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• 제59권2호
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• pp.1-17
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• 2009

This study is to understand the characteristics of Korean Women's Jeogories in modern times on the changes of its color and coloration over the time. The research was that the characteristics of the costumes produced in modern times ($1890{\sim}2000$) can be categorized into six periods according to the change of times. 1106 women's Jeogories were researched intensively in order to understand them, the conclusions are following: When the Chi-Square Test is applied to conduct cross analγsis of the said six periods divided on the basis of relevant theories, it is found that there is just partial difference in the hues in1890-1959 while there has been a big change in the hues of all Jeogories since 1960. It also seems that such a sudden change In hues took place till the end of the 1970s but there have been no significant difference and no distinct changes in hues sin[e the 1980s. As for color tones, high luminosity and low chroma hues were mainly used in all periods, but low luminosity and high chroma hues have been frequently used since the 1960s. It indicates that the long-used conventional and traditional colors gave way to various colors which were freely applied according to the tendency of individualism In the selection of colors as well. As for the coloration, one-color arrangement was predominant in white clothes while the combination of main color Y and supplementary rotor R was overwhelming in two-color arrangement. After the 1960s, not just the five major rotors but diverse colors, including bluish green, dark blue, were used, even varied patterns for linings.

• 디자인학연구
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• 제17권4호
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• pp.223-232
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• 2004

가로 안이 보행공간은 가로가 존재하는 지역특성에 따라서 보행자가 보행 시 시각적으로 느끼는 이미지가 다르다고 할 수 있다. 이러한 지역특성은 가로형태를 조성하는 가로의 물리적인 공간구조에 기인한다. 즉, 가로의 구조적인 차이에 의해서 보행자는 지역의 차이를 다른 이미지로 인지하게 된다. 어떠한 가로구조가 지역의 특징적인 이미지를 창출하는 가로구조인가, 이러한 구조에 부가적인 요소로 작용하는 것은 과연 어떤 요소들인가를 지역가로의 보행공간을 중심으로 연구가 필요하게 되었다. 연구범위는 보행공간구조와 이미지를 분석하기 위하여 보행자들이 많이 모이는 번화한 지역의 가로를 선정하였다. 선정된 지역의 가로 중에서 차선 수를 기준으로 4차선이상의 가로 중ㅇ서 보행공간의 구조를 분석하였다. 분석 결과 선정된 10개의 보행공간의 이미지는 Df/H(보도 폭과 연도건물의 높이)와 D/H(가로 폭과 연도건물의 높이)의 비율의 차이로 2개의 그룹으로 나뉘는 것을 알 수 있었다. 이렇게 2개의 그룹으로 나뉘는 보행공간의 이미지는 어떤 이미지라고 할 수 있는지를 알아보기 위하여 경관이미지를 평가할 때 사용하는 형용사들을 사용하여 2그룹의 이미지를 추출할 수 있었다. 그 중 하나의 이미지는 “번화함의 이미지”이며 다른 하나는 “쾌적함의 이미지”라고 할 수 있다. 또 선정지역의 보행공간의 연도건물의 성격을 중심으로 분석한 결과 2개의 그룹이 상업지역과 업무지역으로 나뉘어 지는 것을 알 수 있었으며 “번화함의 이미지”는 상업지역에, “쾌적함의 이미지”는 업무지역의 보행공간의 이미지라고 인식된다고 할 수 있다. 본 연구로 4차선이상의 가로구조를 가진 보행공간에서 보행자가 느끼는 가로이미지의 차이는 보도 폭과 연도건물의 높이의 차이, 가로 폭과 연도건물의 높이의 비율의 차이에서 따라 다른 이미지를 인지하게 된다는 것을 알 수 있었다. 이 연구의 결과는 지역의 특성을 부여하는 가로를 디자인할 경우, 가로구조 특히 보행공간의 구조를 형성의 지침이 될 것으로 사료된다.

• 대한치과보철학회지
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• 제42권5호
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• pp.556-571
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• 2004

Statement of problem: Surface texture of the implant is one of the important factors of the implant success, especially in the immediate implant loading. Many methods of the surface treatment of implant have developed and introduced. Purpose : This study was to evaluate the effects of the Ca-P coating implant crystallized the hydroxyapatite on the surface by the removal torque test and the histomorphometric analysis in vivo. Material and methods: 135 screw type implants, 4.0mm in length and 3.75mm in diameter were used in this study. Implants were divided into 3 groups and treated in the different mothods. Group I was not treated, Group II was treated in the SLA method, and Group III was treated in the Ca-P coating with the anodizing method and the hydroxyapatite was crystallized on the surface with the hydrothermal treatment. Firstly, the surface roughness of each group was measured, 45 rabbits were used in this experiment. Two implants were inserted on right tibial metaphysis and one implant was inserted on left side with the alternating order. After the healing periods of 3, 5, and 12 weeks, the rabbits were sacrificed to evaluate the osseointergration by the removal torque test and the histomorphometric analysis. Results : 1. In the analysis for the surface roughness, Group II showed the highest roughness. And Group III showed higher secondly. There was a significant difference one another statistically 2. In the removal torque test, Group III and II were significantly higher than Group I. There was no statistical difference between Group III and Group II. 3. For all Groups, the removal torque values at 12th week were significantly higher than at 3rd and 5th week. 4. In histomorphometric analysis, the bone implant contact rates of Group III and II were higher than that of Group I at 3rd and 5th week. There was a significant difference at 5th week. 5. In histomorphometric analysis, the bone implant contact rate of Group III and II increased from 3rd week to 5th week, but decreased at 12th week. In Group I, the contact rate at 12th week was significantly higher than at 3rd week and 5th week.

• Journal of Preventive Medicine and Public Health
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• 제34권2호
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• pp.131-140
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• 2001

Objectives : During March-May, 2000, a measles outbreak occurred at Youngduk, Korea. This county is divided into two areas with different historical and socioeconomic background. The outbreak occurred in one of these areas. We conducted a comparative epidemiologic study on the two areas in order to evaluate the factors related to the epidemic. Materials and Methods : We selected two groups, grades 3 and 5 in a primary schools in each area. We investigated outbreak-related factors using parent-questionnaires, the vaccination history from the student's health record and the records concerning the recent measles-outbreak from the local health center. Serologic test on measles-IgG and -IgM antibody was done. Results : The infection rate was 31.5% for the epidemic area and 3.7% for non-the epidemic area according to clinical or serological criteria (p<0.001). No difference was seen in the measles vaccination rate, residence at the time of vaccination or past measles infection history between the two areas. In the epidemic area, the attack rate for the 4-6 year-old MMR booster group(20.5%) was higher than the non-booster group(32.4%), but was not found significantly. Vaccine efficacy was 29.6% in the epidemic area and 87.0% in the non-epidemic area (p<0.001). The IgG level and positive rate were significantly different between the two areas (median 10727 IU/ml, 98.9% in epidemic area; median 346 IU/ml, 85.9% in the non-epidemic area, p<0.001). However, the IgG level and positive rate between the measles-cases and non-cases were not significantly different. Conclusions : This outbreak took place in mostly vaccinated children. These results suggest that a reduction of herd immunity for immunity failure after vaccination may be one of the feasible factors related to the outbreak pattern in the two areas. The results of the IgG level and positive rate suggest that re-establishment of a normal value for IgG level and of a qualitative method for IgG are needed.

• The Korean Journal of Physiology
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• 제14권1호
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• pp.1-5
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• 1980

This study was under taken to investigate the influences of predictable or unpredictable stress upon gastric ulceration, and the hippocampectomy upon the ulceration order the stressful conditions. Sixty male albino rats(Sprague-Dawley strain) were divided equally into 3 groups: One was the hippocampal group(N=20) which received hippocampal ablation by suction, another was the cortical control group(N =20) which received partial cortical ablation over the hippocampus, and a third was the normal control group(N=20). Each group was further divided into two subgroups: One was the predicted subgroup(N=10) in which animals could predict the imminent stressful stimuli by hearing a sound(1,000 Hz, 2 sec in duration) 3 sec before the onset of the stress, and the other was the unpredicted subgroup(N=10). After starvation for 24 hours, but water ad libitum, each rat received the electric stimulation(3 mA, 60 Hz, 2 sec in duration, and once per minute in average) for 6 hours via a pair of electrodes attached on the tale. The electric stimulation served as the stress causing the gastric ulcer. Five hours after completion of stimulation, the stomach filled with the physiological saline was removed under deep anesthesia and spread out on a small glass plate. The numbers of the ulcer in each stomach were counted and the shape was examined under the dissecting microscope. Results obtained were as follows: 1. The mean numbers of the ulcer of the predicted subgroups were significantly larger than those of the unpredicted subgroups in the normal control and the cortical control groups, but there was no difference between the values of the two subgroups in the hippocampal group. 2. The mean numbers of the ulcer of the predicted subgroups in the normal control and the cortical control groups were larger(but not significant) than that in the hippocampal group. It is inferred from the above results that the prediction of the stress strengthens the effect of the stress on the gastric ulceration, and the hippocampus facilitates the effect of the prediction of the stress.

• 복식문화연구
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• 제19권5호
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• pp.1031-1048
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• 2011

The purpose of this study was to investigate the status of domestic and foreign power blogs that serve as professional source of information and to clarify the difference of the criteria for the certification and selection of power blogs. The study also analyzed the configuration of contents and the characteristic of categories of the power blogs. Eleven domestic blogs were examined, of which ten were certified as power blogs on several portal sites and one blog was operating in English. Furthermore twelve foreign blogs were examined, of which ten blogs were selected from the graded list of www.alexa.com for the Fashion Power Blog TOP 20 adopted on www.telegraph.co.uk in 2009, and two noticeable blogs were selected additionally. Data were analyzed by both theoretical and exploratory studies. The exploratory study was conducted by fourteen majors, who took interest in the blogs and were divided into two groups to look at the domestic and foreign sites, from 12 October to 12 November in 2010. The types of blogs were classified by frequency analysis of interactivity, interest provision, information provision and purchase capability. The investigators checked the type of the contents of each blog and the frequencies were used for the classification type. The analysis showed that the frequencies were in the order of information provision, followed by interest provision, and purchase capability for foreign blogs, while interest provision was followed by information provision for domestic blogs. Interactivity, interest provision, information provision and purchase capability were generally reflected in foreign blogs. Rather than interest provision and information provision, however, interactivity and purchase capability were reflected relatively weakly in domestic blogs.

• 디지털융복합연구
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• 제13권6호
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• pp.205-212
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• 2015

본 연구에서는 거울되먹임치료를 이용하여 뇌졸중 환자의 상지 근육 활성도와 상지 기능적 평가에 미치는 효과에 대하여 알아보고자 하였다. 환자는 거울되먹임 치료군 8명과 동작관찰 훈련군 8명으로 나누어 총 8주간 주 5회, 30분간 시행하였고, 상지 기능을 평가하기 위해 뇌졸중 기능회복 평가와 도수 기능 검사를 이용하였다. 위등세모근, 중간어깨세모근, 위팔두갈래근, 노쪽손목굽힘근, 긴노쪽손목폄근의 근활성도를 평가하기 위해 표면 근전도 시스템을 이용하였고, 연구 결과 노쪽손목굽힘근을 제외한 위등세모근, 중간어깨세모근, 위팔두갈래근, 긴노쪽손목폄근의 근활성도와 뇌졸중 기능회복 검사, 도수 기능 검사 점수에서 대조군과 실험군 모두 전, 후 유의한 차이를 보였다. 이에 따라 거울되먹임 치료가 동작관찰 훈련보다 상지 근활성도와 상지 기능을 향상시키는데 효과적임을 알 수 있었다.

• 벤처창업연구
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• 제8권1호
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• pp.183-191
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• 2013

본 연구는 현실요법 집단상담 프로그램이 초등학생의 리더십 생활기술, 사회성, 학급 응집력에 어떠한 효과를 미치는지를 알아보기 위하여 경기도 S지역의 K초등학교 학생을 대상으로 연구에 참가를 희망하는 34명을 모집하여 실험집단 17명, 통제집단 17명으로 무선 배정하였다. 실험집단과 통제집단 간의 사전 검사 검증과 사후검사 검증에 대해서는 비모수적 통계인 Mann-Whitney U Test와 중다선형 회기분석을 실시하였다. 연구결과를 바탕으로 결론을 내리면 다음과 같다. 첫째, 현실요법 집단상담 프로그램을 경험한 실험집단은 통제집단보다 리더십 생활기술에서 통계적으로 유의미한 효과가 있었다. 둘째, 현실요법 집단상담 프로그램을 경험한 실험집단은 통제집단보다 사회성에서 통계적으로 유의미한 효과가 있었다. 셋째, 현실요법 집단상담 프로그램을 경험한 실험집단은 통제집단보다 학급 응집력에서 통계적으로 유의미한 효과가 있었다. 따라서 현실요법 집단상담 프로그램이 초등학생의 리더십 생활기술과 사회성, 학급 응집력에 긍정적인 방향으로 영향을 미친다는 사실을 알 수 있다.