• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 한국농업기계학회 2002년도 동계 학술대회 논문집
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• pp.48-53
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• 2002

가. 작업단계 별 작업수단 및 노동투하시간 -고추재배는 포장준비 등 일부작업을 제외하고는 인력작업에 의존하고 있으며, 육묘에서 수확 및 수확후 포장처리가지의 총 노동투하시간은 266.7시간/10a로 수확작업이 44.5%로 많았으며, 다음으로 육묘, 지주세우기 및 제거, 정식, 방제 순으로 나타났다. 따라서 노력 및 생산비절감을 위해서는 고추재배 기계화가 시급한 것으로 판단된다. 나 일관기계화방안 -고추재배시 기계화를 저해하는 요인으로는 경지규모의 협소함, 재배지의 필지의 분산, 협소한 조간간격, 비닐멀칭 및 지주유인재배, 수확기간의 길이가 길고 횟수가 많음 등으로 나타났으며, 기계화가 곤란한 것으로 나타났으며, 고추재배일관기계화를 위하여는 공동 또는 공정육묘, 트랙터 등 대형기계중심의 포장준비, 정식은 자동정식기보급, 관수·시비자동화와 붐방제기 또는 방제장치시설화, 기계수확이 되어야할 것으로 판단되었다.

• Land and Housing Review
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• 제5권4호
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• pp.315-323
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• 2014

In this study, thermal transmittance which is a parameter to measure the thermal performance was evaluated for an internal insulation versus an external insulation. Then the ISO regulation was applied to evaluate it, and the superiority of an external insulation was verified by the thermal transmittance values. The three zones of apartment housing were selected to evaluate the performance. (1) The junction of an outer wall and a protruded slab : If there is no a thermal bridge protection system, then the values are about same in the two insulation systems, so the protection system should certainly be installed. If it is installed, then the value for the external insulation is 2 times lower than internal system. (2) The junction of a side wall and a flat slab: The value is 0.509W/mK for the internal insulation and about zero for the external insulation. (3) The junction of an outer wall and a division wall: The value is 0.451W/mK for the internal insulation and also about zero for the external insulation. A domestic regulation that could evaluate a thermal transmittance has to be established by applying the ISO regulation for the evaluation of external insulation systems in apartment housing in the future. Additionally, the government must decide which length should be used for the national standard.

• Journal of the Korean Geosynthetics Society
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• 제16권4호
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• pp.231-240
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• 2017

Recently, there have been frequent occurrences of ground sink in the urban area, which have resulted in human and material damage and are accompanied by economic losses. This is caused by artificial factors such as soil loss, poor compaction, horizontal excavation due to the breakage of the aged sewage pipe, and lack of water proof at vertical excavation. The ground sink can be prevented by preliminary restoration and reinforcement through exploration, but it can be considered that it is not suitable for urgent restoration by the existing method. In this study, a model experiment was carried out to simulate the in-ground cavities caused by groundwater flow for developing non-excavation urgent restoration in underground cavity and the range of the relaxation zone was estimated by detecting the around the cavity using a relaxation zone detector. In addition, disturbance region and relaxation region were separated by injecting gypsum into cavity formed in simulated ground. The shape of the underground cavity due to the groundwater flow was similar to that of the failure mode III formed in the dense relative density ground due to water pipe breakage in the previous study. It was confirmed that the relaxed region detected using the relaxation zone detector is formed in an arch shape in the cavity top. The length ratio of the relaxation region to the disturbance region in the upper part of the cavity center is 2: 1, and it can be distinguished by the difference in the decrease of the shear resistance against the external force. In other words, it was confirmed that the secondary damage should not occur in consideration of the expandability of the material used as the injecting material in the pre-repair and reinforcement, and various ground deformation states will be additionally performed through additional experiments.

• Journal of the Korean Society of Radiology
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• 제15권2호
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• pp.265-271
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• 2021

The pattern of the tree's internal swelling depends on many causes. Since it is difficult to detect these various causes of swelling with a general method, if the state of swelling for a long time cannot be confirmed, serious damage to the trees may occur due to enlargement of the swelling area. In the method of acquiring a tree tomography image, an impulse passing through the tree is generated by tapping the sensor with a rubber mallet, and the moving speed is recorded. In this paper, to measure cracks, cavities, and swelling due to physical damage, we developed a 3D viewer that can know the internal state of a tree using a tree cross-section image acquired from Arbotom to determine the degree of swelling inside the tree. Based on this, we tried to present data that can be referred to when surgical operation of trees is required. In order to acquire a tomographic image of a tree, 6 sensors were attached to the three Yangpala and Maple trees, and a 1 m-long tree was measured using the Arbotom program, and a 3D image was implemented through the 3D Viewer created using MATLAB. In addition to simply acquiring images, the cross-sectional length and volume of the tree were measured. In the actually produced 3D Viewer, the length of the part where the swelling of the maple tree occurred was 33.12 cm, and the swelling of the yangpala tree was measured as 21.41 cm. The volume of the maple tree was measured to be 78.832 ㎤. As a result of comparing the cross-sectional image of the Arbotom and the 3D image, the same result as the real aspect of the tree was obtained, so it can be judged that the reliability of the manufactured software is also secured, and data to be applied to the surgical tree operation through the created Viewer is provided. It is believed that the damage will be minimized.

• The Journal of the Korea Contents Association
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• 제11권4호
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• pp.164-176
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• 2011

To get an implication for desirable direction for Collaboration between Reporter & Producer, I found that had 4 modes of collaboration such as, Producer System, Reporter System, Double Reporting System, Co-Work System, and each was distinguished by field cover, on-mic, editing, writing. Producer system and Reporter system got no chemical synergy because of simple array of single reports due to physical assemble. The achievements of collaboration was birth of new news which had different duration, visual, sound & perspective. It also offered fertile soil for new program and genre literacy of 8 o'clock news. The success factor of collaboration was surprisingly turned out to be personnel rather than system. The balance of reporter & producer was also good factor. But the wall between 2 groups was so high that, after disappearance of extraordinary leader, system began to crumble and at last program was repealed.

• Parasites, Hosts and Diseases
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• 제23권2호
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• pp.260-268
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• 1985

An acephalic budding Cysticercus of 1.2 cm long was removed surgically at the abdominal wall of a Korean man. The worm revealed abnormal buds on the bladder wall and absence of suckers and hooklets in the scolex body. The buds were of two histologic types; branching bud covered with normal tegumentum and with subtegumental cells of normal density, and buds of proliferated subtegumental cells with lacunae formation. On the bases of the morphologic features, it was identified as a racemose cysticercus. This case confirms that its extracranial location is possible.

• Proceedings of the Korea Concrete Institute Conference
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• 한국콘크리트학회 2008년도 추계 학술발표회 제20권2호
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• pp.919-922
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• 2008

This paper reports the physical and shrinkage properties of concrete using expansive additive(E) and three shrinkage reducing admixtures(SRA1, 2, 3) in order to reduce shrinkage of concrete. For the properties of fresh concrete, the use of SRA1, 2, 3 results in a increase in fluidity and decrease in the dosage of super plasticizer as much as 0.05$\sim$0.1%. And For the properties of hardened concrete, the use of SRA1, 2, 3 results in a decrease in compressive, tensile and flexural strength slightly. For drying shrinkage properties, the use of SRA3 is the most effective for reduction of shrinkage, and the next best way to reduce shrinkage is combination with expansive additive(E) and shrinkage reducing admixture(SRA) or the using of expansive additive(E).

• Journal of the Korean Recycled Construction Resources Institute
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• 제5권4호
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• pp.450-457
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• 2017

This study is to develop high quality floor mortar which can be applied in construction sites using EXFG(Expansive admixdure Flue Gas desulfurization gypsum). First, as the substitution rate of ALS(Aluminum Slag) increased, the flow is increased proportionally. EXFG showed a tendency to decrease with increasing substitution rate. Also, in the case of the setting time of 5% of ALS replacement rate, the setting time of Plain compared to EXFG was decreased by 5~20%. The compressive strength increased with the ALS replacement ratio at 0%, 5% and the EXFG replacement ratio at 1%. The strength was increased when the ALS replacement ratio was more than 10%. In the case of ALS replacement rate of 0% and 5%, drying shrinkage compared to plain was decreased by about 10~25% regardless of EXFG replacement rate.

• Journal of the Korean Society of Propulsion Engineers
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• 제12권1호
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• pp.57-63
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• 2008

In combustor of SCRamjet of air-breathing engine type, the flow duration time is very short because of the supersonic air flow. In this short duration, the whole process of combustion should be done, so it is very important to study supersonic combustion technologies. In this study, we focus fuel-air mixing enhancement method using cavity and conducted 3-dimensional Navier-Stokes computational analysis. Cavity height is fixed by 10mm, length is changed from 0 to 40mm. There is a supersonic jet injection downstream of the cavity and the hole size is 1mm. As a result, the higher ratio of cavity length/height is, the higher value of vorticity gets. The increased area of vorticity expands to upper and sidewise combustor. However, the stagnation pressure loss which generates thrust loss becomes higher when the vorticity is higher. Considering these result, we can conclude that optimized design which considers the highest mixing performance and the least stagnation pressure loss is needed.

• Transactions of the Korean Society of Mechanical Engineers A
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• 제37권11호
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• pp.1361-1369
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• 2013

This study performs a computational fluid dynamics (CFD) analysis of the inner flow of a multihole injector nozzle by using ANSYS CFX 13.0. Based on the obtained results, a design of experiment (DOE) was performed and applied to investigate the effects of injector nozzle design parameters on cavitation. To analyze the design sensitivity and signal-to-noise ratio (S/N ratio), the hole diameter, hole length, hole angle, and K-factor of the nozzle hole were selected as design parameters, and the effect of these parameters was investigated at 16 experimental points. Consequently, it was found that the effect of the K-factor on the cavitation and inner flow of the injector nozzle is the greatest. Thus, the selection of a suitable K-factor is important in nozzle design considering cavitation flow.