• Proceedings of the Korea Society for Simulation Conference
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• 2003.11a
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• pp.35-40
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• 2003

This paper presents a method for designing layout on the yard and evaluating alternative designs of the layout by applying simulation. The method is based on the concepts of the conventional port container terminal with a perpendicular yard layout. In general, yard design of the container terminal is consists of the two major parts. One is to divide yard area between the number of sections and the number of runs and the other is to decide the number of equipment that is the yard truck and yard crane. In the past days, this design was depended on the experience of the terminal operator and the structure of the conventional terminal layout because it is a very complex decision problem. In this paper we suggest the method of yard design as a conceptual procedure and estimate the efficiency of the container crane and the optimal the number of equipment using the simulation. Numerical examples are provided in order to illustrate the conceptual procedure. As the example, the suggested method and simulation are applied to the virtual container terminal with a perpendicular yard layout. In the results, the number of sections and runs on yard area, the number of yard truck per container crane and the number of yard crane per run are decided. In additional, the traffic among blocks on yard layout is estimated in terms of rate.

• Fire Science and Engineering
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• v.32 no.5
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• pp.34-39
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• 2018

In this study, the experiment conditions for the variation of heat release rate in compartment space were constructed to analyze the effects of fire spread and the operation time of sprinkler in accordance with the heat loss of the sprinkler's heat element. The compartment composed of fire board (width = 0.3 m, height = 0.5 m, length = 3.0 m), are manufactured to measure the temperature distributions in the inner space, the mass loss rate and heat release rate during the experiment of N-heptane pool fire test. Also, the operation time of sprinkler is analyzed with the installation of sprinkler and C-factor using Fire Dynamics Simulator Ver.6 under the experiment conditions. The results show that the operation time of sprinkler, which has RTI $100(m{\cdot}s)^{0.5}$ operating temperature $70^{\circ}C$, is 30 s~60 s for C-factor = 0 and 1, 62 s~92 s for C-factor = 3, and 120 s over for C-factor = 5, respectively.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.2
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• pp.644-648
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• 2019

This study examined effects of the wall thermal conductivity coefficients on the thermal fluid phenomenon of a compartment fire. The reduced scale compartment was 0.4 m in width, 0.6 m in length and 0.6 m in height with a fire-board, which has a thermal conductivity coefficient of $0.18W/m{\cdot}K$. The local temperature at a 0.37 m height and the overall heat release rate were measured under the following experiment conditions: a $0.12m^2$ opening area and $0.01m^2$ pool size of a gasoline fire. The numerical results obtained by the Fire Dynamic Simulation were compared with the experimentally measured temperature. The deviations were within 10 % in the period of the steady state for maximum heat release rate (4.8 kW). The numerical results show that the average temperature of the compartment wall decreases by approximately 71 % with increasing thermal conductivity coefficient from $0.1W/m{\cdot}K$ to $100.0W/m{\cdot}K$ on the fixed heat release rate.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 2009.05a
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• pp.239-242
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• 2009

최근 3 차원 측정 기술을 활용한 운동 기능성의 향상을 위한 연구가 활발히 진행되고 있다. 그 예로 3 차원 인체 정보를 이용한 의복패턴 제작 시에 필요한 절개선으로 피부상에서 동작 시 늘어나지 않는 선(Lines of Non-Extension, LoNE)을 찾아내어 활용한 연구가 발표된 바 있다. 이러한 LoNE 은 기존 의복구성을 위한 봉제선이나 기능선으로 활용될 때 동작기능성을 저해하지 않는 특징이 있다. 이에 본 연구에서는 스포츠웨어에서 활동성이 큰 상체의 어깨부위에서 Lines of Non-Extension 을 탐색하고자 하였다. 연구 방법으로는 20 대 후반 남성 2 명을 대상으로 체표의 등 부분에서 3cm 간격으로 계측점을 표시한 후 3D 인체 데이터 (Cyberware, WB)를 획득하였다. 측정시의 자세는 팔을 $30^{\circ}$, $90^{\circ}$, $135^{\circ}$, $180^{\circ}$ 외전시켰다. 피부 표면에서의 길이 변화는 구획의 크기를 달리하면서 가로, 세로, 사선방향으로 동작에 따라서 측정하였다. 변화량은 정자세($30^{\circ}$)를 기준으로 A 라 하였을 때, 기준자세와의 차이가 가장 큰 변화량을 보인 자세를 B 라 하고 A 와 B 간의 차이로 계산하였다. 연구결과, NASA 의 Biosuit 에서 소개된 Iberall(1970)의 LoNE 중 진동둘레를 포함한 팔 부위와 등, 어깨 부위에서 유사한 라인을 찾았다. 본 연구에서와 같이 구획별 사선방향 피부 변화량을 측정하는 것은 피부면에 숨겨진 인간공학적 의복 기능선을 탐색하는 데 효과적임을 확인하였다.

• The Korean Journal of Pesticide Science
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• v.17 no.1
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• pp.20-26
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• 2013

This study was carried out of investigate the effect of weed control methods on the growth of 'campbell early' grape at the vineyards which was divided into the 18 zone ($3.5m{\times}5.5m/zone$) in the grape research institute. It's investigated control effects, growth and quantity of grape and dominant weed of July~August by sprayed glufosinate ammonium and paraquat dichloride each 3 times, fabric covering, grass planting (Festuca myuros), mechanical weeding (3 times). The weed showed total of 16 species at the vineyards. Late-May to early growth stage of grape was dominated Chenopodium album and Trifolium repens, but to late growth stage of grape from mid-July was dominated Erigeron canadensis, Echinochloa crus-galli and Chenopodium album. Weed control effect of 10 day after treatment showed fabric covering 100%, grass planting (Festuca myuros L.) 95.3%, mechanical weeding 81.9%, glufosinate ammonium (3 times) 98.1% and paraquat dichloride (3 times) 90.4%, respectively. Growth of grape was higher herbicides treatment and mechanical weeding than others. Yield tended to be higher glufosinate ammonium (3 times) and paraquat dichloride (3 times) each 12.6 kg/tree, 12.3 kg/tree than others.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2002.02a
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• pp.494-500
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• 2002

본 연구의 목적은 DGPS와 자이로 센서를 장착하여 무인으로 콤바인을 직선주행, 선회 및 곡선주행, 직진주행 중 1 m 오프셋(offset) 주행시켰을 때, 무인 자율주행의 성능을 분석하고 개선하는데 있다. 콤바인의 무인자율주행 시스템은 콤바인의 현재위치를 인식하고, 주행하고 있는 콤바인의 주행방향을 감지하여 미리 설정된 경로를 따라 자율적으로 주행하며, 주행 중에 장애물이 검출되면 정지할 수 있도록 개발하였다. 콤바인의 무인 자율주행시스템은 DGPS의 입력 신호로부터 콤바인의 현재위치를 결정하고, 자이로 센서의 입력신호로부터 주행방향을 알 수 있다. 또한 장애물의 감지를 위한 초음파 센서, 콤바인의 주행방향을 조정하는 유압 작동부, 좌.우의 조향레버를 조정하는 서보모터 시스템, 마이크로 컴퓨터로 구성된 제어기와 입출력 인터페이스로 구성되어 있다. 콤바인 자율주행시스템의 프로그램은 DGPS 신호, 자이로 센서 등을 수신하는 수신 프로그램, DGPS 신호등으로부터 관련 변수들을 분석하여 콤바인의 조향수준을 결정하고, 유압실린더 등을 제어하는 제어 프로그램과 콤바인의 이동경로를 저장하는 저장 프로그램으로 구성되어 있다. 콤바인의 무인주행 실험결과 RMS 오차는 50 m 직선주행에서 7.52 cm, 20 m 직선주행 후 1 m 오프셋 된 30 m의 직선주행에서 21.85 cm, 20 m 직선주행 후 90$^{\circ}$선회하여 25 m 직선주행에서 7.55 cm, 반지름 23 m의 원주 사분면 곡선주행에서는 25.98 cm로 각각 나타났다. 소 구획의 포장에서 벼는 가로 방향으로 25~30 cm, 세로 방향으로 15~20 cm의 간격으로 심어져 있다. DGPS 신호에 의한 위치 결정을 할 때 자체 오차 10 cm를 고려하여도 콤바인이 직선구간 및 선회구간을 주행하며 수확작업이 가능함을 알 수 있었다. 그러나 곡선구간에서는 최대오차가 65.5 cm로 매우 크게 나타나, 콤바인을 무인 자율주행으로 수확하기에는 어려움이 있는 것으로 나타났다. 실제 포장은 이론적인 완전한 직선보다는 작은 굴곡이 있는 곡선의 형태가 이루어져 있으므로 주행 오차를 감소하기 위해서는 기계시각을 이용하면 보다 정밀한 조향을 이룰 수 있을 것으로 예상된다. 포장에서 DGPS 신호, 자이로 센서 등을 이용한 콤바인의 무인주행 장치는 무인 수확작업을 위한 가능성을 보여주었고, 일부의 센서의 기능을 개선하면 만족한 성능을 나타낼 수 있을 것으로 판단된다.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.54 no.2
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• pp.203-209
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• 2009

Yield monitoring is one of a precision agriculture technology that is used most widely. It is spatial variability analysis of yield information that should be attained with yield monitoring system development. This experiment was conducted to evaluate spatial variability of yield and grain moisture content in rice paddy field, and their relationships to rice productivity. It is necessary to minimize sampling interval for accurate yield map making or to control cutting width of rice combine. Considering small rice plots such as $0.2{\sim}0.4$ ha, optimum size of sampling plot was below 15 m more than 5 m in with and length. In variable rate treatment field, average yield was similar, but yield variation was reduced than conventional field. Gap of yield by another plot in same field was bigger than half of average yield than yield variation was significantly big. Therefore yield measuring flow sensor must be able to measure at least 300 kg/10a more than 1000 kg/10a. Variation of moisture content in same field was not big and spatial dependance did not appear greatly. But, variation between different field is appeared difference according to weather circumstance before harvesting. Change of spatial dependence of yield was not big, because of field variation of moisture content is not big.

• Fire Science and Engineering
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• v.33 no.6
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• pp.120-125
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• 2019

A real-scale combustion test was conducted on a vinyl flooring in a divided space, with 50 mL of an inflammable liquid sprayed on it. The combustion behavior of the vinyl flooring was studied in real time, and the carbonization patterns of the surface and cross-sections of the carbonized vinyl floor were analyzed. When the flame ignited by gasoline reached its peak, a continuously flaming region, intermittent flaming region, plume region, etc., were formed. The combustion of 50 mL gasoline on vinyl flooring took 26 s, and a halo pattern was observed. This test involved spraying kerosene evenly on the vinyl flooring and attempting to ignite the flooring using a gas torch, which failed. After the combustion of the vinyl flooring was complete, its carbonized range was measured to be 600 mm in length and 380 mm in width, and the carbonized area was 1000 ㎟. Heat transformed the coated layer of surface of the carbonized vinyl flooring into a carbonized layer, which became harder. The analysis of cross-section of the boundary surface of the carbonized vinyl flooring using a stereoscopic microscope showed that the vinyl flooring was bubbling, and that the white boundary layer at the bottom of the coated layer had disappeared.

• Journal of the Korean Arthroscopy Society
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• v.9 no.2
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• pp.232-237
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• 2005

Purpose: To evaluate the effectiveness of arthroscopic direct cystic removal of popliteal cyst using 70 degree arthroscopy and posteromedial portal. Materials and Methods: From January 2003 to January 2004, 21 patients(23 cases) with popliteal cyst have been treated by direct cystic decompression with arthroscopy. The average age of the 21 patients was 54 years(range 35 to 78 years). There were 5 males and 16 females. Of the 23 cases,8 cases were occured in right side and 11 cases were occured in left side. 4 cases were both sides. In all cases, preoperative MRI were performed to detect combined intraarticular pathology. At 6 months and 1 year postoperatively, follow-up ultrasonography were performed to detect recurrence of cyst. We used Rauschning and Lindgren criteria for clinical evaluation. Results: All cases had no recurrence and no complaints of pain, swelling, or functional impairment at 1 year after surgery. At ultrasonography, no recurrence were founded. One complication was occurred. Postoperatively, Rauschning and Lindgren criteria were more than grade 1. Conclusion: Arthroscopic direct cystic removal using arthroscopy and posteromedial portal is an effective method in popliteal cyst surgery.

• Journal of the Korean Arthroscopy Society
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• v.5 no.1
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• pp.22-26
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• 2001

Purpose : To confirm the efficacy of arthroscopic synovectomy fur the pigmented villonodular synovitis in the knee. Materials and Methods : Between October 1996 and February 2000, the arthroscopic synovectomy had been performed in six patients(six knee joints), whose diagnoses were confirmed by pathologist. All patients complained of painful swelling in involved knee and four of the six patients had trauma history. There were three male and three female patients. Average age was 35.8 years ranging from 16 to 67 years. Follow up period was average 22.7 months(range, $13\~53$ months). Results : According to arthroscopic findings, there were three localized forms and three diffuse forms. At their last follow-up examinations, all patients had improvement in pain, swelling and range of motion and there was no evidence of recurrence. Conclusion : Complete arthroscopic excision is the definitive treatment for localized pigmented villonodular synovitis and meticulous arthroscopic excision through all portals including posterior portal can be considered as a valid alternative to traditional open synovectomy for the patients with diffuse pigmented villonodular synovitis.