• Restorative Dentistry and Endodontics
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• 제32권6호
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• pp.550-558
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• 2007

The purpose of this study was to evaluate the insertion depth of several brands of master gutta percha cones after shaping by various Ni-Ti rotary files in simulated canals. Fifty resin simulated J-shape canals were instrumented with ProFile, ProTaper and HEROShaper. Simulated canals were prepared with ProFile .04 taper #25(n=10), .06 taper #25(n=10), ProTaper F2(n=10), HEROShaper .04 taper #25(n=10) and .06 taper #25(n=10). Size #25 gutta percha cones with a .04 & .06 taper from three different brands were used: DiaDent; META; Sure-endo. The gutta percha cones were selected and inserted into the prepared simulated canals. The distance from the apex of the prepared canal to the gutta percha cone tip was measured by image analysis program. Within limited data of this study, the results were as follows 1. When the simulated root canals were prepared with HEROShaper, gutta-percha cones were closely adapted to the root canal. 2. All brands of gutta percha cones fail to go to the prepared length in canal which was instrumented with ProFile, the cones extend beyond the prepared length in canal which was prepared with ProTaper. 3. In canal which was instrumented with HEROShaper .04 taper #25, Sure-endo .04 taper master gutta percha cone was well fitted(p < 0.05). 4. In canal which was instrumented with HEROShaper .06 taper #25, META .06 taper master gutta percha cone was well fitted(p < 0.05). As a result, we concluded that the insertion depth of all brands of master gutta percha cone do not match the rotary instrument, even though it was prepared by crown-down technique, as recommended by the manufacturer. Therefore, the master cone should be carefully selected to match the depth of the prepared canal for adequate obturation.

• Journal of the Korean Society of Hazard Mitigation
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• 제10권2호
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• pp.143-149
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• 2010

The river master plan was established every 10 years in Korea. The basin characteristics of 62 small and medium size rivers of which master plans were recently established during the past three years in Gyeonggi-do were investigated, and design rainfalls and design floods in the past and the latest were compared and analyzed. It was predicted that basin data and flood estimating method changed design flood. The quantitative amount of design floods were analyzed for 6 basins like Gungunchen etc. As the results, the increasing factors of design flood were the application of critical duration time, temporal time of rainfall and the increase of CN value. The decreasing factors of design flood were the application of Huff's rainfall distribution instead of Mononobe one and the ARF. The application of critical duration time increased flood about 60% whereas the application of Huff's rainfall distribution method estimated less flood than Mononobe about 62%. Considering critical duration time and changing rainfall distribution were the most important factors of increasing or decreasing design flood. However, trends of flood variation were differently analyzed by factors in 6 basins because characteristics of topography, weather, hydrology and hydraulic were different, now that correlations were not found between factors and flood variation. Flood variation is evaluated by complex effects of factors so new flood recalculated by reasonable methods should be considered as design flood.

• The Journal of Korean Institute of Communications and Information Sciences
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• 제28권9A호
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• pp.702-709
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• 2003

In this paper, we propose an efficient and QoS-aware MAC scheduling algorithm for Bluetooth, which considers both throughput and delay performance of each Master-Slave pair in scheduling decisions, and thus, attempts to maximize overall performance. The proposed algorithm, MTDPP (Modified Throughput-Delay Priority Policy), makes up for the drawbacks of T-D PP (Throughput-Delay Priority Policy) proposed in [6] and improves the performance. Since Bluetooth employs a master-driven TDD based scheduling algorithm, which is basically operated with the Round Robin policy, many slots may be wasted by POLL or NULL packets when there is no data waiting for transmission in queues. To overcome this link wastage problem, several algorithms have been proposed. Among them, queue state-based priority policy and low power mode-based algorithm can perform with high throughput and reasonable fairness. However, their performances may depend on traffic characteristics, i.e., static or dynamic, and they require additional computational and signaling overheads. In order to tackle such problems, we propose a new scheduling algorithm. Performance of our proposed algorithm is evaluated with respect to throughput and delay. Simulation results show that overall performances can be improved by selecting suitable parameters of our algorithm.

• The Journal of Korean Academy of Prosthodontics
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• 제38권2호
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• pp.147-159
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• 2000

The purpose of this study was the evaluation of spectral transmission of the commercial three shade guides and the relationship of hue, value, and chroma according to the transmission rate. The spectral transmittance of three shade guides - Vita Lumin Shade Guide, Vintage and Unibond Shade Guide, and Vitapan 3D-Master Shade Guide - were measured. For direct transmission measurements, each shade tabs were placed at the entrance port of the 1mm diameter intergrating sphere. The intensity of the light source passing through the shade tabs to the right angle was continuously recorded for wavelength from 400 to 700 nm. A transmission spectrum and digital data were obtained for each measurement and they were evaluated using Microcal Origin program. The obtained results of this study were as follows : 1. In Vita Lumin Shade Guide, sum of the transmission rate of the shade tabs at the wavelength 400-700nm was decreased in agreement with the arrangement order at each A, B, C, D group, except D4 shade tab. However, there were no relationships between the transmission rate of the shade tabs and the value-oriented. 2. In Vintage and Unibond Shade Guide, sum of the total transmission rate of the shade tabs was decreased in agreement with the arrangement order at each A, B, C, B group. When all shade tabs arranged in value-oriented, transmission rate was accord with the order, except D4 shade tab. 3. When shade tabs of the Vitapan 3D-Master Shade Guide have the same value and hue, sum of their total transmission rate decreased in accordance with the chroma-oriented. When the shade tabs have the same value and chroma, there were no differences from the order of the transmission rate to the various hue type. However, in the 'R' tabs of reddish hue type, the transmission rate increased at the long wavelength range area. In conclusion, we need the quantitative analyzing instruments in transmission determination. Vitapan 3D-Master Shade Guide covers the tooth color space taking into account the parameters of the systematic value, chroma, hue oriented, and the transmission rate relatively accorded with that sequence.

• (The)Study of the Eastern Classic
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• 제55호
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• pp.193-221
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• 2014

This study aims to analyze trends of advanced research of "Muyedobotongji". The conclusions are as following in these. First, the number of theses related with "Muyedobotongji" is 47 in total including 29 master's theses and 18 doctor's theses. The sports science comprises the largest proportion of study including 23 master's degree and 12 doctor's degree. Besides sports science field, "Muyedobotongji" is analyzed in various study fields such as library and information, engineering, science of art and culture contents. In master's theses, They focused on practical ways of "Muyedobotongji". But "Muyedobotongji" is conducted by perspective of the humanities in doctor's theses. Second, There are 72 theses related with "Muyedobotongji" in scientific journal. Regarding these in detail, there are 35 theses in sports science, 12 theses in Korean history, 7 theses in martial arts, 5 theses in dance studies, 4 these in Korean studies, 2 theses in Chinse studies, 2 theses in art history, 1 these in Japanese literature and 1 thesis in military science. This fact helps us understand "Muyedobotongji" is studied actively in sports science field. Third, the future research directions of "Muyedobotongji" Should be considered in 3 categories. first, it needs to do interdisciplinary fusion research. Through this, it can complement insufficient parts of existing researches. Second, it needs to make standard Key words. The unified Key words are able to use communicating in different field of scientific journals without confusing. Third It needs to build data bases which are applied to martial art areas. It can provide chances for both Korean martial arts and "Muyedobotongji" to be practiced in culture contents.

• Journal of the Korean Society of Marine Environment & Safety
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• 제27권2호
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• pp.219-227
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• 2021

This study aimed to determine the importance of the policies formulated through the Ministry of Maritime Affairs and Fisheries' master plan for Seafarer's policy. To confirm the importance of the Seafarer's policy, AHP analysis was conducted on the 3 main policies and 15 auxiliary policies established by the master plan for Seafarer's policy. To analyze the reliability of the survey, we investigated the inconsistency ratio of 34 respondents retrieved. We found that 25 respondents validated the reliability of the findings. The analysis showed that the policy of establishing a stable supply and demand system was the most important among the main policies for seafarers, while the policy of fostering seafarers linked to jobs was the most important one among the auxiliary policies. By group, the government recognized establishing a stable supply and demand system as a priority of policy. Dif erences were found on the fact that improving working conditions and expanding welfare were important for seafarers. This study, which analyzed the importance of the Seafarer's policy through AHP analysis, has the following implications. We established guidelines to enhance efficiency, such as budget allocation by policy according to the importance in implementing Seafarer's policies. Furthermore, our study can be used as basic data for establishing a master plan for Seafarer's policy by comparing differences in importance per group.

• Journal of Internet of Things and Convergence
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• 제9권3호
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• pp.69-74
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• 2023

Smart museums based on the growth of online exhibition can be seen as in line with the movement of the 4th Industrial Revolution. By combining art and technologies, they enable viewers to experience culture and art. This study examined the cases of the Dunhuang Museum, the Palace Museum, and the China Arts and Crafts Master Museum to assess or identify how China is leading by accepting the technology of the fourth industry and applying the technology. In common, Chinese smart museums are widely used for collecting enviromental data, establishing integrated digital applications, and preserving collections, services, management, and exhibitions through VR, and AR. Through the case of the Chinese Smart Museum, this study identified the online exhibition as a space that exists in another dimension rather than an image replica with excellent operational utility. Therefore, online exhibitions are the best medium to expand the space, and viewers can explorethe museum's exhibition room and engage with all the contents of the museum without visiting the museum in person. Through the online exhibition of smart museums, visitors and viewers can be transformed into more active cultural consumers and develop collective capabilities.

• Journal of Christian Education in Korea
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• 제73권
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• pp.73-91
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• 2023

This study aims to provide basic data for revitalizing creativity research related to early childhood teachers by analyzing creativity research related to early childhood teachers. For this study, 103 master's and doctoral dissertations in Korea, which were searched through the National Assembly Library and the Research Information Sharing Service (RISS), were selected under the themes of 'early childhood teacher', 'creativity', and 'creativity research trends'. The frequency and percentage were calculated by analyzing creativity research related to early childhood teachers with five criteria: research period, research content, research method, research subject, and creativity factor. As a result of the study, first, as for the trends of creativity research related to early childhood teachers, 91 master's theses (88.3%) and 12 doctoral theses (11.7%) were conducted from 1991 to 2022, focusing on master's theses. Second, trends by research content were found in 20 basic studies (19.4%) and 83 practical studies (80.6%). Creativity research related to early childhood teachers is being actively conducted centering on practical research. Third, trends by research method showed 96 quantitative studies (93.2%), 7 qualitative studies (6.8%), and 0 literature studies (0%). Creativity studies related to early childhood teachers were being conducted with a focus on quantitative research. Fourth, the trend by research subject consisted of 100 studies (97.1%) related to early childhood teachers and 3 studies (2.9%) related to pre-service early childhood teachers. Fifth, trends by creativity factor were found in 56 studies (54.4%) related to teacher's variables and 47 studies (45.6%) related to creativity education methods. Studies related to teacher's variables were relatively higher than creativity education methods. As a result of this study, there is a lack of Christian education research in creativity research related to early childhood teachers, so it is expected that it will be done in the future.

• The Journal of Korean Institute of Communications and Information Sciences
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• 제40권11호
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• pp.2178-2187
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• 2015

Bluetooth Low Energy (Bluetooth LE) is a representative break-through communication technology for wireless personal area networks on nowaday. In this environment, most of significant performance should be aiming to energy efficiency due to the policy for manufacturing light-weighted communication devices derived from requirement of world IoT market, and many researches have been developed to satisfy this requirement. While Bluetooth LE has been leading the low power communication technology required from the current market by employing duty cycle and frequency hopping approaches, it couldn't address the problem of reliability on broadcast transmissions. The main goal of this paper is aiming to addressing this problem by suggesting a new method. Furthermore analytic evaluations would also be proceeded to find objective results in the view point of broadcast transmission efficiency from Master device.

• Magazine of the Korean Society of Agricultural Engineers
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• 제32권E호
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• pp.1-19
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• 1990

Abstract Over the last several decades, crop production in the United States increased largely due to the extensive use of animal waste and fertilizers as plant nutrient supplements, and pesticides for crops pests and weed control. Without the application of animal waste best management, the use of animal waste can result in nonpoint source pollution from agricultural land area. In order to increase nutrient levels and decrease contamination from agricultural lands, nonpoint source pollution is responsible for water quality degradation. Nonpoint source pollutants such as animal waste, ferilizers, and pesticides are transported primarily through runoff from agricultural areas. Nutrients, primarily nitrogen and phosphorus, can be a major water quality problem because they cause eutrophic algae growth. In 1985, it was presented that Watershed/Water Quality Monitoring for Evaluation BMP Effectiveness was implemented for Nomini Creek Watershed, located in Westmoreland County, Virginia. The watershed is predominantly agricultural and has an aerial extent of 1505 ha of land, with 43% under cropland, 54% under woodland, and 3% as homestead and roads. Rainfall data was collected at the watershed from raingages located at sites PNI through PN 7. Streams at stations QN I and QN2 were being measured with V-notch weirs. Water levels at the stream was measured using an FW-l Belfort (Friez FWl). The water quality monitoring system was designed to provide comprehensive assessment of the quality of storm runoff and baseflow as influenced by changes in landuse, agronomic, and cultural practices ill the watershed. As this study was concerned with the Nomini Creek Watershed, the separation of storm runoff and baseflow measured at QNI and QN2 was given by the master depletion curve method, and the loadings of baseflow and storm runoff for TN (Total Nitrogen) and TP (Total Phosphorus) were analyzed from 1987 through 1989. The results were studied for the best management practices to reduce contamination and loss of nutrients, (e.g., total nitrogen and total phosphorus) by nonpoint source pollution from agricultural lands.