• Restorative Dentistry and Endodontics
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• v.34 no.5
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• pp.450-459
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• 2009

The aim of this study was to measure the initial dynamic modulus changes of light cured composites using a custom made rheometer. The custom made rheometer consisted of 3 parts: (1) a measurement unit of parallel plates made of glass rods, (2) an oscillating shear strain generator with a DC motor and a crank mechanism, (3) a stress measurement device using an electromagnetic torque sensor. This instrument could measure a maximum torque of 2Ncm, and the switch of the light-curing unit was synchronized with the rheometer. Six commercial composite resins [Z-100 (Z1), Z-250 (Z2), Z-350 (Z3), DenFil (DF), Tetric Ceram (TC), and Clearfil AP-X (CF)] were investigated. A dynamic oscillating shear test was undertaken with the rheometer. A certain volume ($14.2\;mm^3$) of composite was loaded between the parallel plates, which were made of glass rods (3 mm in diameter). An oscillating shear strain with a frequency of 6 Hz and amplitude of 0.00579 rad was applied to the specimen and the resultant stress was measured. Data acquisition started simultaneously with light curing, and the changes in visco-elasticity of composites were recorded for 10 seconds. The measurements were repeated 5 times for each composite at $25{\pm}0.5^{\circ}C$. Complex shear modulus G*, storage shear modulus G', loss shear modulus G" were calculated from the measured strain-stress curves. Time to reach the complex modulus G* of 10 MPa was determined. The G* and time to reach the G* of 10 MPa of composites were analyzed with One-way ANOVA and Tukey's test ($\alpha$ = 0.05). The results were as follows. 1. The custom made rheometer in this study reliably measured the initial visco-elastic modulus changes of composites during 10 seconds of light curing. 2. In all composites, the development of complex shear modulus G* had a latent period for $1{\sim}2$ seconds immediately after the start of light curing, and then increased rapidly during 10 seconds. 3. In all composites, the storage shear modulus G" increased steeper than the loss shear modulus G" during 10 seconds of light curing. 4. The complex shear modulus of Z1 was the highest, followed by CF, Z2, Z3, TC and DF the lowest. 5. Z1 was the fastest and DF was the slowest in the time to reach the complex shear modulus of 10 MPa.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.34 no.2
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• pp.16-26
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• 2016

In this paper, we collected information on Palgyeong of the Gangneung area that were scattered around several literatures, and analyzed and interpreted regional distribution, elements of scenery and inherent meanings from various angles. we shed light on the origin and the meaning of Palgyeong, which have been passed down in the Gangneung area. Palgyeong of the Gangneung area have been accumulated and expanded for a long period of time, since Goryeo up to the modern times, and it does not simply reflect the beauty of natural scenery, but also reflect historical facts and sentiments rooted in this region. In addition, given the comprehensive veiw of Palgyeong of the Gangneung area and in consideration of its type and distribution of the eight sceneries the most common format is similar to Sosang(瀟湘類似型). What are repeatedly appearing among them include 'smoke from cooking supper' and 'catching fish', showing the living conditions of local residents of Gangneung at the time, which refers to the fact that Palgyeong consisted of village units. Palgyeong in the Gangneung area are distributed in diverse ranges between the city and Nujung. Most of Palgyeong are clustered in the east of Gangneung city and in the region tangent to Gangdong-myeon and Gujeong-myeon. When we consider the situation where most of Palgyeong in the Gangneung area are distributed in this region, it suggests that the region occupies the heart of scenery of Gangneung. Palgyeong of the Gangneung area consists of 60% natural factors, 36% humanity factors, and 4% other factors, where the natural factors hold the beauty of nature itself and the humanities and other factors hold the legends and history contained in the targets. The sceneries expressed by Palgyeong cannot be individually separated. Namedaecheon, Jukdobong, Sumseokcheon, Sumdulmaeul, Gunseongang, Pungho and Kyungpoho were connected to Nujung and Hongjamam, and they eventually became a panorama. Hansongjung, Hwanseondeung, Hansongsa, Pungho and Gunseongang are related to Hwarang of Silla and have become representative historical sceneries of the Gangneung area. Judging from the fact that currently non-existing sceneries such as Kyeonjodo, Hansongjung and Gulsansa remained in Palgyeong and been passed, Palgyeong have positioned imaginary spaces of the Gangneung people beyond simply expressing sceneries. In conclusion, Palgyeong in the Gangneung area are aesthetical objects and while at the same time, they are historical and cultural space, and furthermore, we can see that they still remain as imaginary spaces.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.34 no.2
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• pp.1-15
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• 2016

This study aims at the consideration of the usages of traditional waterscape elements, which are difficult to define their concepts and their differences and it has been proceeded mainly with analysis of literature. It elicited various waterscape types by extracting the place names associated with the watersacpe elements from the chapter "Sancheon" of the volumes Gyeongsang-province in "Sinjeung Donggukyeojiseungram", which is a government-compiled geography book in the early period of Joseon Dynasty, and drew the features of each waterscape element by interpreting the dictionary definition and the original text and studying the similar examples. The results of study are drawn as follows. 1. The chapter "Sancheon" includes 22 types of waterscape elements and they are classified by means of locations and water-flow forms: River Landscape, Lake & Pond Landscape, Coast landscape. 2. River landscape maintaining constant natural water-flow constitutes the linear type, related to the class of stream, which includes 'Su(water)', 'Gang(river)', 'Cheon(stream)' and 'Gye(brook)' and the dotty type, created by the nature of trenched meander rivers, which includes 'Tan(beach)', 'Roe(rapids)', 'Pok(waterfall)' and 'Jeo(sandbank)'. 3. Lake & Pond Landscape forming water collected in a certain area constitutes 'Ho(lake)', which is a broad and calm spot created around mid and down stream of river, 'Yeon(pool)', 'Dam(pond)', 'Chu(small pond)', which are naturally created on the water path around mid and down stream of river, 'Ji(pond)', 'Dang(pond)', 'Taek(swamp)', which is collected on a flatland and 'Cheon(spring)', 'Jeong(spring)' which means gushing out naturally. 4. Coast Landscape includes 'Ryang', 'Hang', which are the space between land and an island or islands, 'Got(headland)' which sticks out from the coast into the sea, 'Jeong(sandbank)' which forms sandy beaches and 'Do' which shows high appearance frequency by reflecting the geographical importance of islands. This study comprehended the diversity of traditional waterscape elements and drew the fact that they are the concept reflecting the differentiated locational, scenic and functional features. That way, it understood the aesthetic sense on nature, which ancestors had formed with the interests in natural landscape and the keen observation on it, became the basic idea elucidating the characteristic on Korean traditional gardens, which minimize the artificiality and make nature the subject.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.30 no.1
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• pp.57-65
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• 2012

This work attempted to study the properties of expression of ground, the composition of outlook and the implications of the connotative symbolic scenery throughout investigating the properties of expression content and method of the scenery, outlook, viewpoint, natural features for each drawing and intention of making 4 old maps, which had been made in the period of the Great Korean Empire and had been called 'Wansan-dohyoung(完山圖形),' 'Jogyeongdan- bigak-jaesil-dohyoung(肇慶壇碑閣齋室圖形),' 'Jeonju-geonjisan-dohyoung(全州乾止山圖形)' and 'Jogyeongmyo-gyounggijeon-dohyoung(肇慶廟慶基殿圖形),' and analyzing the correlation between their drawings. For this aim, observatory investigation by using a map, on-spot investigation, analysis involving the satellite images and internet were carried out with literature review simultaneously. The result of investigation could be sum up as follows. Gyounggijeon(1410), Jogyeongmyo(1771) and Jogyeongdan(1899), where are the core space to lay the historically firm foundation for securing the fact Jeonju is the home of the Royal Family of Joseon, had been built, fixed and extended for giving legitimacy to the Joseon Dynasty and a part of strengthening of royal authority. And these had played an important role of spiritual mainstay from early in the Joseon Dynasty to the era of the Great Korean Empire and had been managed and maintained continuously. It is grasped that the 4 maps consist of Sanhyuoungdo(山形圖; a kind of a mountain map), which is the map for showing a burial place of Lee Han(李翰), the founder of the Joseon Dynasty, and its auxiliary drawings and these had been drawn intensively to justify dignity and authority of the Imperial Family and the Emperor after the name of country was renamed the Great Korean Empire as a part of national undertaking. In detail, Wansan-doghyoung is the key map for announcing the existence of Jogyeong-myo, Gyounggijeon and Jogyeongdan in Jeonju and informing their locations and Geonjisan-dohyoung is the map of divination based on topography for highlighting the geomantic justification of the founder's mausoleum. Jogyeongdan-bigak-jaesil-dohyooung is the partial map detailing for Geonjisan-dohyoung. Jeonju-geonjisan-dohyoung and Jogyeongmyo-gyounggijeon-dohyoung had employed the binary reduced scale and the bird-eye view method and in the above maps, Geonji Mountain is the main mountain and these maps make an exaggeration of the main geographical features, centering Wangjabong and Euimyoso, unlike the real geographical features. Also, the other main geographical features, which are found in the burial place, are expressed in detail by changing the view. In the point of view of 1 set being consisted of 4 maps, 'Wansan-dohyoung' has the property not only as Gunhyoundo, which Gun and Hyoun mean a unit of the administrative district, respectively and Gynhyoundo is a kind of the map for recording their locations, but also as the map of showing their locations. On the other side, 'Jogyoungmyogyounggijeondohyoung' is a kind of lay-out drawing as a partially detailed map. In addition, it has been found out that 'Jeonju-geonjisan-dohyoung' and 'Jogyeongdan-bigak-jaesil-dohyoung' is not only Pungsu- hyounggukdo having the function of Sanhyoungdo but also a detail drawing. On the base of these properties, it is considered that the functionality as a serial map had been strengthened, unlike the existing old maps.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.7 no.5
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• pp.982-991
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• 2006

The screen quota system is one of the most controversial issues in the Korean film industry. There are two different points of view regarding the system. Some say it is highly effective to protect and nurture Korean movies. However, others argue that it hurts the duality of the Korean movies. The number of days, for which Korean movies have to play on local screens, has been reduced to 73, starting on July 1st, 2006. Actually, it is 50 percent fewer than the previous year. In facL Korea has implemented the screen quota. system two times. First, it was practiced from 1935 to 1945, during the Japanese colonial period. This was to regulate imported movies, especially American ones, as the Japanese government was to use movies for the political propaganda. In 1935, the number of foreign movies screened had to be less than three fourths of the total. And they gradually reduced the size by two thirds in 1936, and again by half in 1937. After the attack on Pearl Harbor when the Pacific War happened, Japan completely banned importing American movies in Korea. The reason why it regulated the imported foreign films is to increase the number of domestic movies, both Japanese and Korean. It was for making propaganda films fur carrying the war. The second practice of the screen quota is from 1967 to the present year. It was designed to boom the Korean film industry. However, the competitive power of Korean films has not been improved in spite of the practice of the system. Moreover, the film industry has gone through the depression. Korean film agencies have occupied the Korean film market thanks to the protection by government. The founding of the film agencies has been strongly regulated. So has importing foreign movies. Under the special protection like this, Korean film agencies have been enjoying the monopoly In the mean time, they have pursued income not by making quality movies but by importing foreign movies. As a result, cinema audiences turn away form Korean films and prefer foreign movies. Furthermore, the screen quota system hurts the relationship between film producers and distributors, imposing the duties only on theaters. In short, the screen quota system has satisfied neither film producers, theater runners, nor film goers. In other words. the excessive protection has weakened the competitive power of Korean film industry.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.7 no.6
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• pp.1407-1415
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• 2006

Japan started to colonize Korea in 1910. It's when It forced and made Chosun sign on the Treaty of Protectorate. The Chosun faithfully practiced Japan's colonial policy over Korea. Futhermore, it stopped many Koreans from an anti-Japanese movement and tried to make Koreans have a positive attitude towards Japan. For this, Japan advertised the policy called Nae-sun-il-che which meant Korea and Japan were a community together from the same root. Ultimately, it targeted on absorbing Korea within their territory. With this goal, Japan kept on practicing the policy to acculturize and brainwash Koreans, totally depending on force and pressure from 1910 to 1919. However, this policy had changed by the overall anti-Japanese movement happening on March 1st 1919. Saito, the third governor-general who was appointed laster on, made an effort to win over He favor of Koreans in a less forceful way of the cultural politics. The change of policy had been specified in diverse actions such as permitting civil mass-media bodies forming the observation groups and opening conferences. In the case of daily newspapers, Japan had permitted only the ones by the Government-General of Chosun such as Maeil-shinbo, Kyunsung-ilbo, and Seoul Press before, but then other civil newspapers In Korean stated to be released. Along His Japan formed both Korean and Japanese observation groups to promote the mutual understanding and showed off Japan's goods in the propaganda films by implementing a film department. It's because Japan totally recognized and understood the impact of films. Therefore, Japan distincitively established a film agency for the production of propaganda movies while it banned the civil film production after 1937 when Japan started the war against China and USA in row. So, only one film agency, ruled by the Government-General of Chosun, produced movies from 1942 to 1945.

• Journal of the Korean Geographical Society
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• v.28 no.4
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• pp.321-355
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• 1993

This paper focuses on the geographical pattern of financial activities in the Korean urban system during 1975-1990, based on the assumption that financial activities can reveal control points in Korea's urban economy. In terms of spatial evolution of financial insitutions, different locational characteristics are revealed among different types of financial institutions, implying the role of urban hierarchy. Financial resources are highly concentrated in the capital region, Seoul and Kyonggi Province. Both centralization trends into the large metropolitan cities and relative declines of medium and small cities within the Korean urban system, have been experienced over the study period. Financial activities sustain relatively stable hierarchical structure in the urban hierarchy. Regarding the financial flows, dominant flow zones centered on major metropolitan cities are identified, clearly showing a prominant role of Seoul in financial flows in the entire urban system.

• International Journal of Highway Engineering
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• v.9 no.4
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• pp.117-127
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• 2007

The exposed aggregate PCC(EAP) pavements have been successfully used in Europe and Japan as low-noise pavements. Coarse aggregate are exposed on the pavement surface texture of EAP by removing mortar of surface. The pavement surface texture should maintain not only low-noise characteristic but also adequate skid resistance level during the performance period. Skid resistance decreased with wearing and polishing of tire and pavement surface due to the repetition of tire-pavement contact. Since the tires mainly contact the exposed coarse aggregate, the shape and rock type of coarse aggregate significantly influence wearing and polishing of EAP pavements. The test for resistance to abrasion coarse aggregate by use of the Los Angeles machine(KS F 2508) and the method of test for resistance to abrasion coarse aggregate by use of the Accelerated Polishing Machine(ASTM D 3319-90) are generally used to evaluate polishing characteristics of aggregate. In this study, polishing of coarse aggregate of different five rock types were evaluated by KS F 2508(LA abrasion test) and ASTM D 3319-90(PSV method). The results of LA abrasion test and PSV method were contrary to each other. Since LA abrasion test is estimated the quantity of abrasion by the impact of aggregate, it may not be adequate to evaluate the polishing of aggregate by the repetition of tire. In the case of PSV method, the resistance of polishing is estimated the skid resistance variation of polished aggregate after repetition of tire. The PSV method is adequate for the evaluation on polishing of coarse aggregate. From the test results of PSV method, it was founded that rock type, specific gravity, coarse aggregate angularity, flat or elongated particles in coarse aggregate are significant to the resistance characteristic of coarse aggregate.

• Korean Journal of Remote Sensing
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• v.35 no.6_2
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• pp.1117-1132
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• 2019

Forest covers 30% of the Earth's land area and plays an important role in global carbon flux through its ability to store much greater amounts of carbon than other terrestrial ecosystems. The Gross Primary Production (GPP) represents the productivity of forest ecosystems according to climate change and its effect on the phenology, health, and carbon cycle. In this study, we estimated the daily GPP for a forest ecosystem using remote-sensed data from Moderate Resolution Imaging Spectroradiometer (MODIS) and machine learning algorithms Support Vector Machine (SVM). MODIS products were employed to train the SVM model from 75% to 80% data of the total study period and validated using eddy covariance measurement (EC) data at the six flux tower sites. We also compare the GPP derived from EC and MODIS (MYD17). The MODIS products made use of two data sets: one for Processed MODIS that included calculated by combined products (e.g., Vapor Pressure Deficit), another one for Unprocessed MODIS that used MODIS products without any combined calculation. Statistical analyses, including Pearson correlation coefficient (R), mean squared error (MSE), and root mean square error (RMSE) were used to evaluate the outcomes of the model. In general, the SVM model trained by the Unprocessed MODIS (R = 0.77 - 0.94, p < 0.001) derived from the multi-sites outperformed those trained at a single-site (R = 0.75 - 0.95, p < 0.001). These results show better performance trained by the data including various events and suggest the possibility of using remote-sensed data without complex processes to estimate GPP such as non-stationary ecological processes.

• The Journal of Korean Society for School & Community Health Education
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• v.2 no.1
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• pp.67-84
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• 2001

This study was conducted to examine beauty shop workers' views of job. Data were collected from the workers in Seoul, Daegu, Pohang, Junjoo, and Kimhae from June 1, 2000 to August 31, 2000. The results of this study are summarized as follows. 1. According to general characteristics of the subjects, 28,7% of them was female; 94.2% 'specialized in hair'; 46.4% 'below twenty nine years old'; 47.1% 'married'; 59.7% 'highschool graduate'; 33.9% 'worked for below three years'; 28.5% 'monthly income of five hundred thousand to nine hundred ninety thousand won'; 62.3% 'working for above twelve hours a day' ; 41.0% 'above five workers' ; 40.6% 'working in city'. 2. 54.8% of the respondents thought that they were in good health. 76.3% of them smoked and 54.8% drank. 62.8% of them did not exercise and 78.7% was under stress. 61.5% responded that they chose the job because of its possibility of professional vocation. 91.0% of them obtained the beauty skill from beauty schools. 3. Among the factors which influenced job satisfaction, 'stable job and life security' was highest(43.9%), while 'interest in the job and amount of pay' was lowest(3.2%). 'Personal ability and use of originality' was 19.4% and 'harmonious relationship with fellow workers' was 18.1%. 'Job environment' was 7.1% and 'harmonious relationship with higher workers' was 4.5%. 4. The level workers' view of job was $113.8{\pm}17.3$ points on the basis of 150 points. On the basis of 75 points, each item showed it points in order of self-development($22.3{\pm}3.8$), service for customers($20.1{\pm}3.1$), vocational mission($15.6{\pm}3.1$), harmony with the others($18.9{\pm}3.5$), working environment($18.6{\pm}3.6$), and working condition($14.3{\pm}5.1$). 5. Among the reasons why they considered leaving the job, 24.0% of them considered it because they could not free time, while 15.4% considered it because undesirable living environment or long distance from home. 15.0% thought it because they could not receive proper treatment as much as they worked and 12.8% thought they overworked. 6. When they move into new working places, they consider such factors as good working environment(24.1%), good place to open their own beauty shops(16.7%), good beauty shop to learn beauty skill(15.6%), chance to have job training(9.5%), and close place from home(9.0%). 7. 40.6% of the respondents wanted to leave the job, while 32.3% of them did not want to leave the job. The intention of leaving the displayed significant difference in the variables of age, working period, monthly income, marital status, the number of workers, location of the shop, rank, and reason of selecting the job. 8. According to the results of a regression analysis of factors which influenced job satisfaction, it was affected significantly by intention of leaving job, the number of workers, health condition, level of stress, and monthly income. The beauty shop workers showed low satisfaction level with working environment, working condition, and working mission, They considered leaving the job because of lack of free time, overwork, poor working environment, improper treatment, etc. Therefore, related professionals and organizations must device adequate measures in order to make them work with pride as creators of beauty.