• Journal of the korean academy of Pediatric Dentistry
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• v.29 no.3
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• pp.382-388
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• 2002

In the present study, crown diameters and their sexual differences in deciduous teeth were investigated in children of Chon-ju city, Korea. Plaster casts of the deciduous dentitions obtained from 50 boys and 50 girls were examined. Mesiodistal and buccolingual crown diameters were measured using a digital caliper(0.01mm) according to the definitions of Seipel and Moorees et al. These measurements were performed three times, and intra-observer measurement errors were calculated by the single determination method. The crown index, module and area were calculated in order to provide a comparison of crown proportions. The results obtained were summarized as follows; 1. The mean values of intra-observer measurement errors were 0.255mm and are unlikely to have influenced the statistical analysis. 2. The mean values of mesiodistal and buccolingual crown diameters examined were larger in boys than girls. 3. The mean coefficient of variation was 5.6 in the deciduous dentition. There were a trend for the primary second molar to be the least variable in size of all teeth both in boys and girls. 4. Fluctuating asymmetry is the difference between left and right antimeres in individuals. Primary second molars were less asymmetrical than primary first molars in both dimensions. 5. In maxillary teeth, Crown index is larger in boys than in girls. In contrast, in mandibular teeth, except primary canine, it is larger in girls than in boys. Crown module is larger in boys than in girls and increased progressively from primary first incisor to primary second molar. Crown area is consistently larger in boys than in girls. The minimum crown area is mandibular primary incisor and maximum crown area is maxillary primary second molar.

• Journal of Korean society of Dental Hygiene
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• v.6 no.4
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• pp.325-337
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• 2006

The purpose of this study was to examine the oral health state of the elderly in an effort to pave the way for dental health project planning for the elderly for the city of Jeonju and to help promote the oral health of the elderly population to which health care services weren't accessible a lot. The subjects in this study were 300 elderly people who were in their 60s and up and used 10 different welfare establishments for the elderly in Jeonju. A survey was conducted from May 3 through 13, 2005, by interviewing them in person, and the collected data were analyzed. The findings of the study were as follows: 1. In terms of the period of oral health examination, 44.1 percent of the 66-70 age group, 48.1 percent of the elementary school graduates and 39.4 percent of the house owners had their teeth examined whenever they had a toothache. So their cycle of oral health examination was statistically significantly different according to age(p<.05), education(p<0.001) and form of residence(p<0.001). 2. Regarding the necessity of prosthesis, prosthesis was needed by 52.1 percent of the age group from 71 to 80, 44.3 percent of the women, 48.9 percent of the men, 60.0 percent of the community college graduates and 55.9 percent who rent a house on a deposit or monthly basis. But there was no statistically significant gap among the groups. 3. As for the necessity of oral health education, the necessity of it was absolutely supported by 89.7 percent of the 66-70 age group, 76.0 percent of the women, 87.2 percent of the men, 95.3 percent of the middle school graduates and 87.7 percent of the house owners. Their age(p<.0.01), gender(p<0.05) education(p<0.05) and form of residence(p<0.01) made a statistically significant difference to that. 4. Concerning oral health education experience, 79.3 percent of the high school graduates and 79.8 percent of the house owners had never received oral health education, and that experience statistically significantly varied with education(p<0.001) and form of residence (p<0.001). 5. As to the biggest reason for oral health care, 50.0 percent found it necessary to take care of their teeth to ensure their own perpetual oral health, and 33.7 percent felt the need for that because they had a toothache. The above-mentioned findings indicated that the elderly people were definitely in want of oral health education. Dental hygienists in public dental clinics should serve as dental health educators to address their needs, and regular oral health care programs should be prepared to spread awareness about the importance of oral health among elderly locals.

• Geophysics and Geophysical Exploration
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• v.1 no.1
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• pp.57-63
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• 1998

The electrical resistivity method, one of old and widely used geophysical prospecting methods, has extended its scope to civil & environmental engineering areas. The electrical resistivity imaging technique was performed at the waste disposal site located in Junju to verify the applicability to the environmental engineering area. The dipole-dipole array, with the dipole spacing of 10 m, was applied along eight survey lines. The field data were obtained under the control of automatic acquisition softwares and topographic effects were corrected during processing stage. The processed resistivity images show that very low resistivity develops inside the disposal site and the distribution of low resistivity is exactly in accord with the boundary of the site except the river side. The depth of low resistivity zones is deeper toward the river side, which is interpreted that there is a high possibility for contaminants to be scattered to the river. From resistivity images, it was feasible to deduce the depth of waste disposal as well as the horizontal/vertical distribution of the contaminated zone, which proved the applicability of the electrical resistivity imaging technique to the environmental engineering area.

• Journal of Korean Tunnelling and Underground Space Association
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• v.23 no.5
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• pp.325-337
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• 2021

On the road and rail tunnels, the evacuation pathway and facilities such as smoke-control and fire suppression system are essential in tunnel fire. In the long twin tunnels, the cross-connection tunnel is usually designed to evacuate from the tunnel where the fire broke out to the other tunnel. In twin shield tunnels, the segment lining has to be demolished to construct the cross-connection tunnel. Considering the modern shield TBM is mostly the closed chamber type, the exposure of underground soil induced by removal of steel segment lining is the most danger construction step in the shield tunnel construction. This case study introduces the excavation method using the thrust of large steel pipe and reviews the measured data after the construction. The large steel pipe thrust method for the cross-connection tunnel can stabilize the excavated face with the two mechanisms. Firstly, the soil in front of excavated face is cylindrically pre-supported by the large steel pipe. Secondly, the excavated face is supported by the plugging effect caused by the soil pressed into the steel pipe. It was reviewed that the large steel pipe thrust method in the cross-connection tunnel is enough to secure the construct ability and stability in soil from the measurement results about the deformation and stress of steel pipe.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.22 no.3
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• pp.55-71
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• 2019

The purpose of this study is to propose an evaluation method to assess green environments of streetscapes to improve urban street green spaces in Jeonju City. Through a rapid assessment of urban street green spaces, we suggest an objective basis for expanding street green space as well as for adopting sustainable maintenance and improvement measures. We choose 12 sections of streetscapes (roads and sidewalks) to investigate existing street conditions which have more than four lanes and function as major road axes. Six large roads and six medium roads of Jeonju City center area are investigated as pilot assessment study sites. Site inventory checklists consist of environmental characteristics of streetscape, street tree status, and planting condition evaluation. Environmental characteristics of streetscapes are composed of physical and neighborhood factors. For instance, items for physical factors are types and width of road/sidewalks, paving materials, tree protection materials, and green strip. And surrounding landuse is a neighborhood factor. Assessment items for street tree status are street plant names (tree/shrubs/ground cover), size, and planting intervals. Planting condition evaluation items are tree shape, damage, canopy density, and planting types with existence of adjacent green space. Evaluation results are classified into three levels such as A(maintain or repair), B(greening enhancement), and C(structural improvement). In case of grade A, streetscapes have enough sidewalk width for maintaining green strip and a multi-layered planting(in large road only) with fairly good growing conditions of street trees. For grade B and C, streetscapes have a moderate level of sidewalk width with a single street tree planting. In addition, street tree growing conditions are appeared poor so that green enhancement or maintenance measures are needed. For median, only grade B and C are found as its planting growing foundations are very limited in space. As a result, acquiring enough sidewalk space is essential to enhance ecological quality of urban street green. Especially, it is necessary to have green strip with reasonable widths for plant growing conditions in sidewalks. In addition, we need to consider native species with multi-layer plant compositions while designing street green.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.2
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• pp.104-112
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• 2021

For extrusion processes in the process industry, the need to build smart factories is increasing. However, in most extrusion production sites, the production method is continuous, and because the properties of the data are undeed, it is difficult to process the data. In order to solve this problem, we present a methodology utilizing a near field communication (NFC) sensor rather than water-based data entry. To this end, a wireless network environment was built, and a data management method was designed. A non-contact NFC method was studied for the production performance-data input method, and an analysis method was implemented using the pivot function of the Excel program. As a result, data input using NFC was automated, obtaining a quantitative effect from reducing the operator's data processing time. In addition, using the input data, we present a case where a bottleneck is improved due to quality problems.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.32 no.1
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• pp.40-47
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• 1987

Under the different conditions of planting density and compound fertilizer level, some agronomic and chemical characteristics of burley tobacco were investigated from 1982 to 1984. Leaf area and dry leaf weight per plant, crop growth rate, relative growth rate and net assimilation rate for 40-60 days after transplanting were higher with increasing plant spacing and fertilizer, but leaf area index was lower with increasing plant spacing. At topping stage, the leaf size was increased with increasing plant spacing and amount of fertilizer applied and the stem diameter was increased by increasing plant spacing. Leaf area, leaf weight per plant and weight per unit leaf area of harvested leaf were higher when plant spacing and fertilizer increased. It was estimated that the optimum plant spacing was 105cm x 34cm and level of com-pound fertilizer (N-P$_2$ O$\sub$5/ -K$_2$O =10-10-20) was 263kg/l0a for high yield. There were trends toward increase the contents of total alkaloid and total nitrogen with increasing plant spacing and fertilizer application. There was significant positive correlation between plant spacing and total nitrogen, and between fertilizer application and total nitrogen. The plant spacing of 105cm x 35 to 40cm and 227.5kg/l0a of fertilizer level may be profitable for farm economy and the low nitrogenous leaf.

• The Journal of the Convergence on Culture Technology
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• v.9 no.1
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• pp.697-702
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• 2023

Recently, with the introduction of drones, a core technology of the 4th industrial revolution, various convergence education using drones is being conducted in school education sites. In particular, drone theory and practice education is being conducted in connection with free semester classes and career exploration. The drone convergence education program has higher learner satisfaction than simple demonstration and practice education, and the learning effect is high due to direct practical experience. However, since practical education is being conducted for a large number of learners, it is impossible to restrict and control the flight of a large number of drones in a limited place. In this paper, we propose a monitoring system that allows the instructor to monitor multiple drones in real time and learners to recognize collisions between drones in advance when multiple drones are operated, focusing on education operated in schools. The communication module used in the experiment was equipped with GPS in Murata LoRa, and the server and client were configured to enable monitoring based on the location data received in real time. The performance of the proposed system was evaluated in an open space, and it was confirmed that the communication signal was good up to a distance of about 120m. In other words, it was confirmed that 25 educational drones can be controlled within a range of 240m and the instructor can monitor them.

• Land and Housing Review
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• v.5 no.4
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• pp.325-332
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• 2014

The purpose of this study was to measure the airtightness and Air-Flow Performance for 7th house of small apartment houses adopted window frame-type natural ventilation. All window and living room door is provide with window frame-type natural ventilation, and there is provide with manual controller. As the object of measurement, the 6th type small apartment houses with area of $33m^2$ to $51m^2$ was selected. airtightness performance was measured at the front door using Blower door system. We measured ventilation rate per hour on 50Pa pressure different between inside and outside by the 1st to 6th cases. As a result, when the natural ventilation frame was closed, average amounts are shown as the ventilation rate per hour were 2.27ACH (CASE1). and the result is similar to general apartment house (1.65~4.28ACH). When the natural ventilation frame was open, average amounts are shown as the ventilation rate per hour were 5.87ACH (CASE6). In addition, that's a 3.6ACH increased more than CASE1.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2018.04a
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• pp.42-42
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• 2018

메밀은 마디풀과(polygonaceae)의 메밀속에 속하는 일년생 초본으로 야생종을 포함하여 20여 종이 확인되고 있다. 현재 재배되고 있는 메밀 재배종은 보통메밀(Fagopyrum esculentum Moench)과 쓴메밀(Fagopyrum tataricum Gaertn., 타타리메밀) 등 두 종이 주류를 이루고 있으며 우리나라에서는 보통메밀이 주로 재배되어 왔다. 본 연구는 농업유전자원센터에서 보유중인 보통메밀 341점과 쓴메밀 38점을 봄, 여름에 파종하여 특성조사를 수행하고 재배시기별 생육특성을 비교하기 위해 수행되었다. 봄, 여름 파종은 각각 2017년 4월 14일과 8월 17일에 전주 소재 농업유전자원센터 포장에 하였으며 줄기색, 엽색, 엽형, 개화기, 성숙기, 꽃색, 종피색, 종자모양, 주경절수, 총분지수, 백립중 등 11개 농업형질을 조사하였다. 봄 파종시 개화기는 대부분 5월 25일 전후였으며 성숙기는 6월 말부터 7월 중순까지 분포하였고 여름 파종시는 9월 15일 전후 개화하여 10월 말에 성숙하였다. 줄기색은 홍색의 비율이 높았고 엽색은 연녹색과 녹색이 대부분이었으며 엽형은 화살촉형이 90% 이상이었다. 꽃색은 흰색이 대부분이었지만 연녹색 자원도 40점 조사되었으며 종피색은 연갈색이 70%를 차지하였다. 종자 생산과 관련된 주경절수와 총분지수는 봄 파종과 여름 파종에서 많은 차이를 나타냈으며 봄 재배시 영양생장이 왕성하여 가을 재배보다 많은 주경절수와 총분지수가 조사되었다. 그러나 백립중에서는 여름 파종이 봄 파종보다 무거운 경향을 나타내어 주경절수, 총분지수와 백립중 간 부의 상관관계를 추론할 수 있었다. 일반메밀 유전자원을 국내 수집지별로 나누어 조사한 결과 주경절수와 총분지수는 봄, 여름 파종 모두에서 전남 수집자원이 가장 많았으며, 강원, 경남, 경북, 전북, 충북 수집자원과 유의성있는 차이를 나타내었다. 강원, 충북 수집자원은 제일 낮은 주경절수와 총분지수를 보였으나 백립중은 가장 높게 조사되었다.