• Journal of the Korean Society of Environmental Restoration Technology
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• v.10 no.6
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• pp.139-151
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• 2007

To protect the surface of ground-cutting slopes and ground-raised slopes and to recover environment-friendly slopes at the national road expansion construction between Gamchon and Yaechon, test-construction work was done using several modes of hydro-seeding measures to select a suitable construction method through the field survey; the results were as follows : As a result of survey on physio-chemical characteristics of soil, the average soil inclination on ground-raised slopes was from 4.73 mm to 5.37 mm; the average soil acidity was from pH 6.47 to 6.73; the average soil humidity was within the scope of 0.57~1.70 %,; the average soil inclination on ground-cutting slopes was 9.17~10.43mm; the average soil acidity was pH 6.67~6.77 and the average soil humidity was within the scope of 0.53~1.27 %; considered overall, they showed generally satisfactory base materials for plant breeding. As a result of the number of sprouting individuals, the average sprouting number of individuals on test spots executed by Coir net with Seed spray construction methods and the average number of sprouting individuals on other test spots executed by furrow-digging with Seed spray and Straw mat-mulching measures were 1,172 number of per square meter and 970 number of per square meter respectively; thus they showed higher numerical value comparing with other test spots. Likewise, the average number of sprouting individuals on test spots of the ground-cutting slopes executed by Coir net with Seed spray method and the average number of sprouting individuals on other test spot executed by furrow-digger with Seed spray and Straw mat-mulching measures were found to be 1,107 number of per square meter and 1,105 number of per square meter respectively, whose numerical value showed rather higher other test spots. As a result of a survey on living plants' breeding index [dried weight], the weight in dried state on test spots executed by Coir net with Seed spray method and other test spots executed by furrow-digger with Seed spray and Straw mat-mulching measures on both ground-raised and ground-cutting slopes was found to be higher and showed similar characteristics statistically. As a result of survey on the surface-covering degree of ground-raised slopes, nine weeks after test construction, test spots executed by Coir net with Seed spray method and other test spots executed by furrow-digger with Seed spray and Straw mat-mulching measures showed commonly more than 70% of surface-covering degree, but other test spots showed only below 35% of surface covering degree; especially in case of test spots by Verdvol seed spray measures, they showed 10% of the lowest surface-covering. Surface-covering degree on the test spot of ground-cutting slopes nine weeks after test construction showed more than 75% both executed by Coir net with Seed spray construction method and executed by furrow-digger with Seed spray and Straw mat-mulching measures. As a result of survey on appearing plants on the test spots, there dominates Eragrostis curvula both on ground-raised slopes and on ground-cutting slopes with other seeding plant life's lower breeding and there appear intruders, such as Setaria viridis Beauv, Digitaria sanguinalis Scop, and Chenopodium album var.centrorubrum Makino. As for water-borne excavation and soil's washing-away on the slopes, there happened less washing-away and water-borne excavation with good breeding of plant life on test spots executed both by Coir net with Seed spray construction method and by furrow-digger with Seed spray and Straw mat-mulching measures, but there happened much more soil's washing-away along with water-home excavation at the test spot executed by Seed spray with measures. After the research results of test construction sites are examined overall, it's presumed that furrow-digger with Seed spray and Straw mat-mulching measures [interval between lines is 40cm, 5cm in depth] will be preferred to prevent erosion and water-home excavation of slopes located within the construction sites.

• Korean journal of communication and information
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• v.56
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• pp.175-193
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• 2011

This study explored how South Korean newspapers covered North Korea's second nuclear test in May of 2009. Findings show that South Korean newspapers mostly reported North Korea's nuclear experiment in relatively negative tones. Their coverage mainly focused on the influences of nuclear threat from the North on the military, political and economic areas in South Korea. However, the media's agenda settings and frames were not similar in terms of each paper's political and ideological inclination. Whereas the progressive papers, such as the Hankyoreh and the Kyunghyang Shinmun, recognized that the current nuclear issue in Korean peninsula is getting worse because of South Korea's rigorous pressure on North Korea, the conservative papers, such as the Chosun Ilbo and the Donga Ilbo, see that the deadlock between North and South mainly comes from the system malfunction of North Korea. To prevent the current impasse, the left-side papers emphasized to develop the six-party talk in dealing with North Korean issue, while the right-wing papers paid attentions to the West's sanctions on North Korea and ensuring national security.

• Archives of Plastic Surgery
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• v.38 no.5
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• pp.594-601
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• 2011

Purpose: The frontal sinuses are a pair of triangularly shaped, air-filled chambers lined by mucoperiosteum and located between the inner and outer tables of the frontal bone. Until recently, our understanding of gender variations in craniofacial anatomy has been chiefly built upon anthropometric studies, which typically employ facial surface measurements or plain film radiography. The aim of this study i to determine the sizes of the frontal sinus in both sexes in Koreans. Methods: 95 Korean subjects who underwent maxillofacial 3-Dimensional computed tomography (CT) between January 2009 and December 2009 were enrolled. Frontal sinus dimensions and forehead measurements were taken at midline and at 10, 20, and 30 mm to the left and right of midline using sagittal, coronal, and axial images. The data was analyzed for significant differences between measurements made at the selected points in the frontal sinus, for left to right variations, for gender variations, and for racial differences. Results: The mean thickness of the anterior table ranged from 2.31 to 3.23 mm. Mean anteroposterior depth of the frontal sinus ranged from 7.38 to 9.45 mm and did not vary significantly at any distance from midline. Frontal sinus height was greatest at midline (mean=29.24 mm) and progressively lessened at lateral distances. Mean total width at the level of the supraorbital ridge was 53.66 mm. For all measurements, no significant left to right variation was noted. Comparing the sexes, males were found to have greater dimensions in most frontal sinus measurements, though these differences were only found to be significant at or close to midline. The male forehead was marked by more acute nasofrontal angle ($133.3^{\circ}$ versus $141.6^{\circ}$) and a steeper posterior forehead inclination ($14.9^{\circ}$ versus $7.7^{\circ}$). Conclusion: Using CT imaging, forehead and frontal sinus dimensions have been described. Generally, males had larger overall frontal sinus dimensions. And Korean had similar sized frontal sinus to Caucasian in height and width. But in AP distance Korean had lesser measurement. The result of this study may be helpful in the comprehension of normal size of frontal sinus in Korean.

• The korean journal of orthodontics
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• v.22 no.4 s.39
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• pp.881-920
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• 1992

This study was designed to assess profile preferences among Korean youths in the year 1992. Facial esthetics was evaluated by means of silhouette profiles, eliminating the influence of a number of aspects that may affect judgment when normal lateral photographs are used. The main points of preference to be clarified here are as follows. First, on facial convexity, Second, on nasion depth, Third, on mentolabial sulcus depth, Fourth, on the position of upper and lower lips, Fifth, on facial type according to Angle's classification of malocclusion, Sixth, on Song's tangents. The 54 subjects printed in questionnaire as black and white silhouettes were selected from 300 tracings from cephalometric radiographs of people whose age ranging from 11 to 20 years. Photographs of six female subjects were retouched by computer graphic software and printed in color and black/white photographs which were used for adaptation of eyes of participants in selecting profiles in silhouette. They constitute 2 questions. The 54 subjects were grouped as 22 questions, each of them composed of 6 subjects, according to the aspects to be clarified. Twenty four questions in total were asked to assess profile preferences. For the assessment, the profile line, the facial esthetic triangle, Song's tangents, and Angle's classification of malocclusion were introduced. The profile line is composed of 11 component points which are Trichion, Glabella, Nasion, Pronasale, Subnasale, Labrale superius, Stomion, Labrale inferius, Supramentale, Pogonion, and Gnathion. The facial esthetic triangle is composed of 3 tangents: A-tangent which is the tangent of dorsum of nose, B-tangent which is the line passing through Sn and Ls, and C-tangent which is drawn on the turning point of the curve which lies between mentolabial sulcus (Sm) and pogonion (Pg). Angle's classification has 3 types of malocclusion which are Class I, Class II, and Class III. Class II malocclusion is subdivided into Division 1 and Division 2. The participants of the survey were composed of 861 college students (448 male students, 413 female students) whose majors grouped as Fine Arts. Liberal Arts, and Natural Sciences, and whose mean age 21.8 years. The statistics program SPSS/PC + of SPSS Inc. was used to analyze answers of participants. Crosstabulation, Chi-square test, and Kendall test were done. The conclusions are as follows: First, Korean youths have a tendency to prefer the slightly convex face to the flat or concave face. Second, they prefer a moderately deep nasion. Third, they prefer a moderately deep mentolabial sulcus. Fourth, they prefer the position of lips which are near to Ricketts' E-line. The position of the upper lip which is slightly posterior to E-line is preferred. The upper lip which lies too far anterior or posterior to the lower lip is not perferred. Fifth, they prefer most, according to Angle's Classification of Malocclusion, Class I facial profile which has a slight inclination to Class II division 2. The order of preference is Class I, Class II division 2, Class III, and Class II division 1. Sixth, they prefer the type 2 and 3 of Song's tangents. The facial profile within which A-and B-tangent meet is preferred. The facial profile which has Cotangent that .meets with A-tangent slightly posterior to the crossing point of A-and B-tangent or that parallels with B-tangent is preferred.

• Journal of the Korean Society of Propulsion Engineers
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• v.26 no.3
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• pp.32-42
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• 2022

The strategy to develop a launch vehicle family by bundling multiple rocket engines of a single type has been proven by SpaceX and their reusable fleet comprised of Falcon 9 and Falcon Heavy. In this study, we revisit a potential launch vehicle family out of a 35 tonf-class methalox staged combustion cycle engine and evaluate their utility and performance in various space missions. For example, a Korean version of Falcon 9 can deliver 4.7 tons of payload into 500 km SSO in an expendable mode while the payload is reduced to 2.16 tons in a sea-landing reusable mode. A Korean version of Falcon Heavy can deliver 4.4 tons into GTO when launched from the Naro Space Center, indicating that this common booster core configuration can handle Cheollian 2 albeit the high inclination. Once developed, the same methaloax engine can power the first-stage of smallsat launch vehicles and air launch vehicles.

• Strategy21
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• s.34
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• pp.93-127
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• 2014

During the four years following the sinking of the Cheonan frigate in 2010, the South Korean public opinion has seen changes in four basic ways. First, public polls with respect to the cause of the sinking show that 70% of the people consider North Korea as the culprit, while 20% maintain that it was not an act carried out by North Korea. Second, the opinions relative to the cause of the incident seem to vary according to age difference, generational difference, and educational difference. From 2011, people in their 20s showed 10% increase in regarding North Korea as the responsible party. People in their 30s and 40s still have a tendency not to believe the result of the investigation carried out by the combined military and civilian group. Third, the most prominent issue that arose aftermath of the Cheonan incident is the fact that political inclination and policy preference are influencing the scientific determination of the cause. In other words, scientific and logical approach is lacking in the process of determining the factual basis for the cause. This process is compromised by the inability of the parties concerned in sorting out what is objective and what is personal opinion. This confused state of affairs makes it difficult to carry on a healthy, productive debate. Fourth, rumors, propaganda, and disinformation generated by pro-North Korea Labor Party groups in the internet and SNS are causing considerable impact in forming the public opinion. Proposed Strategy 1. The administration can ascertain public trust by accurately determining the nature of the provocation based on accurate information in the early stages of the incident. 2. Education in scientific, logical, rational methodologyis needed at home, school, and workplace in order toenhance the people's ability to seek factual truths. 3. In secondary education, the values of freedom, human rights, democracy, and market economy must be reinforced. 4. It is necessary for the educational system to teach the facts of North Korea just as they are. 5. Fundamental strength of free democratic system must be reinforced. The conservative, mainstream powers must recognize the importance of self-sacrifice and societal duties. The progressive political parties must sever themselves from those groups that take instructions from North Korea's Labor Party. The progressives must pursue values that are based on fundamental human rights for all. 6. Korean unification led by South Korea is the genuine means to achieve peace in a nuclear-free Korean peninsula. The administration must recognize that this unification initiative is the beginning of the common peace and prosperity in the Far East Asia, and must actively pursue international cooperation in this regard.

• Korean Journal of Culture and Social Issue
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• v.19 no.2
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• pp.87-108
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• 2013

With questionnaires conducted for 613 adult Koreans in Seoul, the present study examined how their social features (income level, political party identification, political values, values of capitalism and egalitarianism) exercise influence on attitudes toward income polarization and their evaluation of government policies. Two groups of participants (high vs. low) for each social feature were formed first. Then their attitudes toward income polarization (liberal vs. conservative) and evaluations of policies (liberal vs. conservative) exercised by government (Participatory vs. Practical) were compared. Results indicated that liberal value was strengthened by liberal value, anti-capitalistic, and conservative value was strengthened by egalitarian values, and party identification. It was also found that party identification partial effect on the judgment of policies exercised by Participatory Government. These findings were discussed in terms of their implications for Korean society and measures for communication constructive for settlement of income polarization were suggested.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.20 no.4
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• pp.344-350
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• 2009

This paper proposes a hybrid antenna with novel beam steering scheme. The antenna have a cassegrain structure composed of two reflectors. The main reflector is designed for high gain performance using parabola curvature, and the sub-reflector is plate and can be rotated by ${\pm}3^{\circ}$. Thus proposed antenna can steer a antenna beam using the inclination of sub-reflector. A feed array composed of 20 elements is adapted as a feeder for electrical beam steering, and the antenna can be possible to steer the beam by the feed array with sub-reflector. Proposed antenna was fabricated to be operated in Ka-band(30.085$\sim$30.885 GHz) for TX and K-band(20.355$\sim$21.155 GHz), which are the operation frequencies of the Korean satellite, Mugunhwa, to provide satellite multi-media service to vehicles. By the performance test, it can be known that the antenna has minimum gain of 47 dBi for TX and 44.4 dBi for TX and can steer the beam by ${\pm}2^{\circ}$ with sub-reflector.

• The Journal of Korean Society for School & Community Health Education
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• v.9 no.1
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• pp.143-156
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• 2008

Objectives: This study was performed to examine the effective health education measures and health education programs for college students and also investigated the demands of restriction on drinking and smoking behavior in public area at the school level. Methods: The data were collected from 446 students of five universities located in Seoul and analyzed with SPSS WIN 10.0 program. Results: 1) Current drinkers were average 87.7% (male 90.1%, female 85.3%) and binge drinker was 68.4% (male 76.5%, female 60.2%). Among all drinkers, 19.4% drank more than eight times per month. As for the rate of smoking, 50.9% among the male student, and 12.1% among females were smokers. Among all smokers. the largest group (41.5%) smoked between >$11{\sim}20$ cigarettes per day. Many of the students started smoking in their middle schools (male 29.8%, female 51.5%). It implies that smoking prevention programs need to be emphasized in these schools. 2) The analysis of the correlation between drinking and smoking shows that no smoking students who drank were 66.2%, but abstainer who is smoker were only 5.7%(p=0.004). Alcohol consumption frequency and amount of smokers were higher than those of nonsmokers (p=0.000). The rate of attempts to reduce drinking was 38.1%, mainly for health reason. More than 34.5% of smoking student had made attempts to quit smoking, but succeeded only 16.9%. 3) As for the needs of moderate drinking and smoking cessation education, 67.8% among female students and 53.6% among male demand special education programs. About effective health education measures on drinking and smoking, 49.3% of drinkers and 35.2% of smokers had an inclination for health educator, and the next were video, campaign and pamphlet. 4) The largest group (45.0%) of respondents had agreed to regulate on drinking behavior, and especially 74.5% of them wants to ban the practice in most public area in school. 35.7% among female students and 27.0% among male desired to extend the non-smoking area on whole campus. The health policy for college students, through various ways, such as education, counseling service, and special program on orientation, should be employed. For public health perspectives, university and college community had to institute the detailed enforcement regulation on drinking and smoking.

• Journal of the korean academy of Pediatric Dentistry
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• v.37 no.2
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• pp.252-259
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• 2010

Trauma commonly leads to ankylosis for the tooth whose periodontal ligaments have been injured. In growing patients, an ankylosed tooth can disrupt alveolar development, resulting in infraocclusion of the affected tooth. Consequently, this causes aesthetic problems during adolescence, interferes with prosthetic treatment due to the inclination of adjacent teeth, and complicates orthodontic dental movement. When the infraoccluded ankylosed tooth is extracted, a considerable amount of alveolar bone is lost, especially in the maxillary anterior region. Moreover, depression of the thin buccal alveolar bone compromises aesthetic restoration. In order to prevent alveolar bone loss, the ankylosed tooth should be treated by decoronation. In the present study, the traumatically injured maxillary incisors of 9-year-old and 10-year-old patients that present infraocclusion accompanied by ankylosis were treated with decoronation procedures. Decoronation procedures were performed when the affected teeth were 2-3 mm below relatively to the adjacent teeth. Moreover, the patients were treated before they get to 16 years old considering the maximum growth peak of the korean adolescents. As the results, there are favorable clinical results associated not only with preservation of horizontal alveolar volume but also with increase in vertical alveolar height after decoronation in growing individuals.