• Maxillofacial Plastic and Reconstructive Surgery
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• 제22권2호
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• pp.174-183
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• 2000

This study was performed to investigate the characteristics of soft tissue profile of the class III malocclusion and to test the yardstick far differential diagnosis between surgical and orthodontic patients. Initial lateral cephalograms of orthodontic group(30 patients) that have acceptable occlusion and profile by orthodontic treatment alone and surgical group(30 patients) that have favorable occlusion and profile by combined surgical-orthodontic treatment were selected in Ajou university hospital. Powell and Burstone II analysis were made on the tracing. Descriptive, comparative, factor, cluster, and discriminant analysis were carried out with computer program. The results were as followings : 1. Patients who received surgery had a more concave profile and a longer lower facial height than patients who received orthodontic treatment alone. 2. Nasolabial angle, ratio of vertical height, and mentolabial sulcus were significantly different at the 5% level. And facial protuberance, upper lip protuberance, mentocervical angle, nasofrontal angle, nasomental angle, mandibular vertical height, angle between cervix and lower face, ratio of mandibular vertical height divided by cervical depth, ratio of vertical height between upper and lower lip, and maxillary protuberance were significantly different at the 1% level. 3. 8 factors were extracted and factor 2, 3, and 8 showed significant differences by factor analysis. 4. Orthodontic group (25) and surgical group (35) were classified by cluster analysis. 5. Discriminant function was D = 0.079Nasomental angle + 0.081Sn-Gn + 3.343Sn-Gn/C-Gn + 1.734Sn-St/St-Me' -26.460, and cutting score was 0, so we can discriminate that orthodontic group has the score above 0, and surgery group below 0. And 91.7% of original grouped cases were correctly classified.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2003년도 제4회 박판성형 심포지엄
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• pp.29-34
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• 2003

In order to study the shearing characteristics of anti-vibration sheet metal which has been bonded by resin, a blanking die of 40.02mm was manufactured to blank a material and it is used to reduce vibrational noise. The variables employed in this study were 1) Clearance 2) types of stripper plate, and 3) types of the die design technique. These variables were used to study the effects on burr height, diameter of product, and camber height. Lastly, the effect of the position of the rubber during blanking was observed. In the case of burr height from experimental investigation, the push-back die, combined with a movable stripper plate, resulted in the concentration of additional pressure between the cutting edges, meaning the crack initiation was delayed. This result was not affected by lubrication, although appropriate lubrication is preferred to enable a longer lasting die in terms of wear, which results from the presence of adhesive as the sheet metal is blanked. In the comparison of diameter measurement, the push-back die, combined with the back pressure from the knock-out plate showed a favorable precision. The use of the push back die with a fixed stripper plate, with a $4.5\%$ clearance, showed better accuracy in the diameter measurement. For comparing camber height, the push back die resulted in less cambering than the drop-through die. Also, the larger the clearance, the greater was the camber height. Considering experimental results, the shearing of anti-vibrational sheet metal is best achieved when the rubber is laying on the top, blanked with a fixed-stripper plate in a push-back die, with a $4.5\%$ clearance.

• 한국산림과학회지
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• 제81권2호
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• pp.146-155
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• 1992

본(本) 연구(硏究)는 임분(林分)의 직경(直徑) 분포(分布) 및 수고(樹高) 분포(分布)에서는 태벌구조(擇伐構造)의 가능성(可能性)을 시사(示唆)하고 있으나 경급별(徑級別) 재적(材積) 분포(分布)에서는 택벌(擇伐)에 이르지 못한 미성숙(未成熟) 구조(構造)를 보여 갱신과정(更新過程)에 있는 것으로 판단(判斷)되는 강원도(江原道) 인제군 기린면 진동리 고재(所在) 천연(天然) 횬효임분(混淆林分)을 대상(對象)으로 이 임분(林分)의 직경(直徑) 및 재적(材積) 생장율(生長率)의 파악(把握)을 통하여 미래(未來) 임분(林分) 구조(構造)의 변화(變化)를 예측(豫測) 함으로서 이 임분(林分)에 대한 택벌작업종(擇伐作業種)의 가능성(可能性)을 점검(點檢)하였다. 매 1년(年) 단위(單位)로 생장율(生長率)을 이용(利用)한 앞으로 30년간(年間)의 임분(林分) 구조(構造)의 예측(豫測)에 의하면 30년후(年後)에 목표직경(目標直徑) 40cm 이상(以上)에서의 본수(本數)와 ha 당(當) 재적(材積), 그리고 매년(每年) 수확(收穫)이 가능(可能)한 대경목(大徑木) 재적(材積)을 충분(充分)히 보유(保有)할 것으로 예측(豫測)되어 택벌목(擇伐木)으로 경영(經營)할 수 있을 것으로 판단(判斷)되었다. 그러나 균형상태(均衡狀態)에 있는 이상적(理想的)인 택벌목(擇伐木)의 대(大), 중(中), 소경목(小徑木)의 경급별(徑級別) 본수(本數) 비율(比率)인 1 : 2 : 7과 재적(材積) 비율(比率)인 5 : 3 : 2를 유지(維持)하지는 못하고 있는데 이는 앞으로 적합(適合)한 조림(造林) 조치(措置)를 통한 조절(調節)이 가능(可能)할 것으로 보인다.

• 한국약용작물학회지
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• 제23권4호
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• pp.319-323
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• 2015

The objective of this study was to establish the optical storage condition in cutting slips of Lycium chinense Mill. We investigated the different influential growth factor of this plant including two soil types (soil and vermiculite) and storage methods (gauze, parafilm, vinyl, and paper). Our result revealed that the formation of axillary bud was highest ($4.8{\pm}0.75ea$) from the cutting slips stored in vinyl and vermiculite treatment. Root length was long ($2.8{\pm}0.13ea$) in parafilm storage using soil. Maximum plant height was $135.33{\pm}12.81cm$ with gauze storage using vermiculite. The number of leaves was maximum ($130{\pm}2.5ea$) at 90 days from the cutting slips of gauze storage using vermiculite. Highest number of fruit was harvested ($149{\pm}16.05ea$) from the cutting slips stored in parafilm and grown in vermiculite. It can be concluded that the storage treatment and soil type influence the affecting to general growth of Lycium chinense Mill.

• 한국산림과학회지
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• 제109권4호
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• pp.468-476
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• 2020

본 연구는 굴참나무 임분밀도관리도 개발을 통해 맹아갱신림의 경영목표별 벌기령을 예측하고자 하였다. 분석에 활용된 표준지 조사자료는 분석용 자료 603개소와 검증용 자료 113개소로 분류하였고, 이를 이용하여 임분밀도관리도의 개발과 적합도 검증을 실시하였다. 임분밀도관리도 구성 모델의 설명력(R2)은 등평균수고곡선식 0.732, 등평균직경곡선식 0.990으로 분석되었다. 재적 생산 최대 벌기령을 분석한 결과, ha당 900본의 맹아 잔존 시 42~44년으로 나타났고, ha당 1,800본을 잔존한 경우 38~42년으로 분석되었다. 3등급재 원목을 생산목표로 설정하였을 때의 벌기령은 지위지수 16일 때 25~28년이 소요되었고, 지위지수 14는 29~33년이 소요되는 것으로 나타났다. 본 연구의 결과는 굴참나무 맹아갱신 임분의 경영계획 수립에 있어서 기초자료로 활용될 수 있을 것으로 판단된다.

• 한국토양비료학회지
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• 제45권6호
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• pp.992-997
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• 2012

수수의 재생력과 양분 흡수력을 이용해 시설재배지에 집적된 토양양분의 효율적 이용방법 개발을 위한 기초자료를 얻고자 비닐하우스에 수수를 재배하여 주요 생육시기별로 예취한 후 재생경의 생육 및 양분흡수 특성을 구명한 결과는 다음과 같다. 예취 후 재생경의 출수 소요일수는 유숙기 예취시 35일로 가장 짧게 나타났으며, 가장 긴 소요일수를 보인 출수기도 44일로 관행재배시보다 짧은 소요일수를 나타냈다. 예취 후의 누적 초장에서는 유숙기에서 379.4 cm로 가장 길게 나타났고, 예취 시기가 늦을수록 작은 경향을 보였으며 가장 짧은 무예취구와는 약 2배의 차이를 보였다. 그러나 수수의 Biomass는 초장과 달리 출수기 예취구가 1.73 Mg $10a^{-1}$로 가장 많은 생산량을 나타냈으며 종실은 무예취구에서 가장 많은 수량을 나타냈다. 식물체 부위별 농도에서 T-N은 잎>이삭>줄기 순으로 나타났으며, 대체적으로 생육초기인 10엽기에서 각 부위별로 높은 양분함량을 보였으며 수확시기에서는 $K_2O$를 제외한 나머지 $P_2O_5$, CaO와 MgO가 줄기보다는 잎에서 높은 함량을 보였다. 지상부의 양분흡수량은 예취시기에 따라 출수기>무예취구>유수형성기${\geq}$유숙기>10엽기 순으로 나타났다. N의 흡수량은 출수기의 $P_2O_5$을 제외한 $K_2O$, CaO, MgO은 무예취구에서 가장 많은 흡수량을 보였으며 평균 흡수량보다 모두 높은 처리구는 출수기와 무예취구로 나타났다.

• 대한안전경영과학회지
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• 제10권2호
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• pp.95-103
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• 2008

The package loading process of the lumbering industry is an operation that after a pair of workers bind three or six lumbers into one unit and cut both ends of the lumbers, transports the weight cargo of 30-50kg by one meter, pack and load at a height of 1.2 meters. This package loading process causes lots of noise and wood dust when workers carry out the heavy work as the above. Therefore we developed the monolithic both ends cutting package loading equipment in order to prevent from getting musculoskeletal disease. An loading bar working system of this equipment is improved from pneumatic pressure system to oil pressure system, furnished the newly designed flow dividers, and developed the new system that a both end array is loaded identically. Also we developed the safety equipment of loading bar in order to prevent workers mistake and overload from malfunction during the package loading process. The main cause of job evasion on working place could be solved by preventing the musculoskeletal disease and improving the working environments.

• 산업공학
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• 제24권4호
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• pp.387-395
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• 2011

This study was aiming to examine work time, frequency, work environment, and postures of retail grocery store workers to evaluate the risk of musculoskeletal disorders. An ergonomic evaluation was conducted using job analysis and posture analysis. The four most time-consuming tasks were inspecting (27.4%), arranging (21.4%), cutting (17.6%), and displaying (15.6%). The height and length of the shelves evaluated in the field was inappropriate for workers. The most common posture was a standing posture with neutral back, and bent head, right upper arm, lower arms, and hands. Finally, this paper concluded that 'arranging,' 'cutting,' and 'displaying' seemed more stressful than other operations. The result of the ergonomic evaluation would contribute to design a better workspace in ergonomics.

• 대한기계학회논문집
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• 제19권9호
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• pp.2089-2104
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• 1995

A novel and efficient cutter path planning method for machining intricately shaped curved surfaces, called the steepest directed tree method, is presented. The curved surface is defined by triangular facets, the density and structure of which are determined by the intricacy and form accuracy of the surface. Geometrical form definition and recognition of the topological features are used to connect the nodes of the triangulated surface meshes for the successive and interconnected steepest pathways, which makes good use of end milling characteristics. The planetary cutter centers are determined to locate along smoothly changing paths and then the height values of the cutter are adjusted to avoid surface interference. Several machined examples of intersecting and intricate surfaces are presented to illustrate the benefits of the new approach. It is shown that due to more consistent geometry matching between cutter and surface(in comparison with the current CC Cartesian method) surface finish can be typically improved. Moreover, the material in concave fillets which is difficult to be removed by ball mills can be removed efficiently. The built-in positioning of cutter to avoid interference runs minutely in the sharp and discontinuous regions. The steepest upward movement of the cutter gives a stable dynamic cutting state and allows increase in the feedrate and spindle speed while remaining the stable cutting state.

• 대한안전경영과학회:학술대회논문집
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• 대한안전경영과학회 2008년도 춘계학술대회
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• pp.135-147
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• 2008

The package loading process of the lumbering industry is an operation that after a pair of workers bind three or six lumbers into one unit and cut both ends of the lumbers, transports the weight cargo of 30-50kg by one meter, pack and load at a height of 1.2 meters. This package loading process causes lots of noise and wood dust when workers carry out the heavy work as the above. Therefore we developed the monolithic both ends cutting package loading equipment in order to prevent from getting musculoskeletal disease. An loading bar working system of this equipment is improved from pneumatic pressure system to oil pressure system, furnished the newly designed flow dividers, and developed the new system that a both end array is loaded identically. Also we developed the safety equipment of loading bar in order to prevent workers mistake and overload from malfunction during the package loading process. The main cause of job evasion on working place could be solved by preventing the musculoskeletal disease and improving the working environments.