• Journal of Life Science
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• v.8 no.5
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• pp.504-508
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• 1998

A study was conducted to evaluate a protein removal characteristics by foam separation. The foam separator was operated in well-mixed tank which would be considered as a completely mixed condition. The feasibility of foam separation to remove protein from fresh and sea water was investigated. Protein removal characteristics of the foam separator were obtained by batch reactor operations. To find the effect of the operating parameter to protein removal rate, the foam separation was carried with variation of initial protein concentration and foam height. The results indicated that the protein removal efficiency was increased with increasing protein concentration and decreased with increasing foam height. The relationship between protein concentration and protein removal rate was evaluated by linear regression.

• 한국지구물리탐사학회:학술대회논문집
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• 2009.10a
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• pp.113-118
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• 2009

An uplift or a subsidence of a wide area can be derived from change of gravity value, change of geoid, change of heights at measurement points etc. In the past decade, 1) the absolute gravity value acquired at a point in Daejeon decreased, 2) the geoid height on the Yellow Sea Area derived from satellite altimetry data increased, 3) the height of the southern part of Korean Peninsula increased. By synthesizing these, we can interpret that the wide area including the southern part of Korean Peninsula and the Yellow Sea is uplifting with the velocity of about 2 mm/yr.

• Journal of the Korea Safety Management & Science
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• v.9 no.4
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• pp.11-16
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• 2007

최근 들어 산업현장 뿐만 아니라 농어촌에도 자동화가 가속화되면서 작업자의 안정성과 편리성을 높이기 위한 다양한 방안이 제시되고 있지만 여전히 농업현장에서 대부분의 작업들이 부적절한 자세로 수행할 수밖에 없는 경우가 자주 발생한다. 본 연구는 쪼그려 앉는 작업자세가 요구되는 각종 농작업에 있어서 적합한 높이의 작업용 좌대를 제공함으로써 부적절한 작업자세를 개선하여 노동 강도를 경감시킴과 동시에 작업능률 향상과 요통 등 근골격계질환을 감소시켜 작업자의 건강과 안전을 증진시키는데 목적을 두었다. 이를 위하여 농작업에서 행해지는 쪼그려 앉는 여러 자세에 있어서 재배작물의 높이에 따라 적절한 작업용 좌대의 높이를 실험을 통하여 규명하였다. 연구결과 쪼그려 앉아 작업을 수행해야 하는 유사한 작업이라도 작업위치에 따라 쪼그려 앉는 작업용 좌대의 적합한 높이는 달라져야 한다는 것을 발견하였다. 즉 작업위치가 5cm 이하이면 작업용 좌대 높이는 10cm가 적절하며 작업위치가 20cm이면 15cm, 작업위치가 40cm이면 20cm가 적절함을 알 수 있었다. 이와 같은 결과를 농작업에 적용한다면 작업조건이 향상되어 편안하고 안전한 자세로 작업을 할 수 있기 때문에 허리, 어깨, 다리 등의 근골격계 질환을 감소시킬 수 있으며 인력작업에 따른 무리한 힘의 소모를 감소시켜 노동력 절감은 물론 생산성 향상을 가져올 수 있다고 판단된다.

• The korean journal of orthodontics
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• v.33 no.5 s.100
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• pp.339-350
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• 2003

The purpose of this study was to investigate the micro-implant height and anterior hook height to prevent maxillary six anterior teeth from lingual tipping and extruding during space closure. We manufactured maxillary dental arch form, bracket and wire, using the computer aided three-dimensional finite element method. Bracket was $.022'{\times}.028'$ slot size and attached to tooth surface. Wire was $.019'{\times}.025'$ stainless steel and $.032'{\times}.032'$ stainless steel hook was attached to wire between lateral incisor and canine. Length of hook was 8mm and force application points were marked at intervals of In. Four micro-implants were implanted on alveolar bone between second premolar and first molar. The heights of them were 4, 6, 8, 10mm starting from wire. We analyzed initial displacement of teeth by various force application point applying force of 150gm to each micro-implant and anterior hook. The conclusions of 4his study are as the following : 1. When the micro-implant height was 4m and the anterior hook height was 5mm and below, anterior teeth were tipped lingually. When the anterior hook height was 6mm and above, anterior teeth were tipped labially. 2. When the micro-implant height was 6mm and the anterior hook height was 6mm and below, the anterior teeth were tipped lingually. When the anterior hook height was 6m and above, the anterior teeth were tipped labially. But lingual tipping of anterior teeth decreased and labial tipping Increased when the micro-implant height was 6mm, compared with 4mm micro-implant height. 3. When the micro-implant height was 8mm and the anterior hook height was 2mm, the anterior teeth were tipped lingually. When the anterior hook height was 3mm and above, labial tipping movement of the anterior teeth increased proportionally. 4. When the micro-implant height was 10mm and the anterior hook height was 2mm and above, labial tipping of the anterior teeth increased proportionally. 5. As the anterior hook height increased, aterior teeth were tipped more labially. But extrusion occurred on canine and premolar area because of the increase of wire distortion. 6. Movement of the posterior teeth was tipped distally during maxillary six anterior teeth retraction using micro-im plant because of the friction between bracket and were Based on the results of this study, we could predict the pattern of the tooth movement according to position of micro-implant and height of anterior hook. It seems that we can find the force application point for proper tooth movement in consideration of inclination of anterior anterior teeth, periodontal condition, overjet and overbite

• KOREAN JOURNAL OF CROP SCIENCE
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• v.42 no.5
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• pp.528-533
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• 1997

This experiment was conducted to determine the effects of cutting height on the yield and nutritive value of brittle culm rice. A brittle culm cultivar, KL501, was compared with a non-brittle culm rice, Seomjinbyeo. The cultivars were grown in paddy until flowering stage at which the first cutting was made followed by the second cutting on October 20. Cutting regime conducted were 0, 5, 10 and 20cm from the surface. Herbage yield, TDN and other nutritive values were measured. As the higher cutting height, crude protein, fat and NFE (nitrogen free extract) contents were increased and crude fiber and ash content were decreased at the first cutting, while those at second cutting were increased except NFE content. Fresh and dry matter yield at 10cm cutting height, Seomjinbyeo was 4.45 and 1.16t /ha, KL501 was 4.71 and 1.14t /ha, respectively. TDN content of first cutting was increased as the higher cutting height, but that of second cutting was decreased. TDN yields of Seomjinbyeo and KL501 at 10cm cutting height were highest by showing 0.63t /ha and 0.61t /ha, respectively.

• Journal of the Korean Society of Marine Environment & Safety
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• v.24 no.2
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• pp.157-162
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• 2018

The increase of risk in port due to the increase in ship size and sea level rises, the standard crown height will increase. In this study, cruise and container ships will need to raise their crown height due to the projected wind pressure areas becoming larger due to the ships' size increase. The mooring assessment was evaluated with the rise of the crown height. The cruise ship of GT 100,000 tons exceeded the permissible breaking force of the mooring line under the crown height conditions of wind speed of 30 kts when the wind direction was $45^{\circ}$ to the direction of the bow. Also, the elevation angle of the pier and mooring line was analyzed and exceeded the crown height, and it was determined that it is necessary to adjust the crown height. Container ships of DWT 100,000 tons were analyzed to exceed the limit of sway motion at the crown height and it was determined that they need to be adjusted to the minimum crown height standard.

• Journal of the Korea institute for structural maintenance and inspection
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• v.24 no.4
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• pp.10-17
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• 2020

The recent earthquake in Korea caused large and small damages to many school building. School building is an important building that is used as a shelter in the event of disaster. Among the seismic retrofit methods, the internal steel braced frame type method is used for its relatively easy construction and excellent performance. In this study, the maximum shear force and displacement were compared and examined by applying the brace frame to existing concrete school buildings. As a result, we verified the adequacy of the analytical model and compared and examined the effect of brace-height ratio on the span of the existing school buildings. The adequacy of the maximum shear force and displacement relationship can be confirmed in the model with a length of 0.3. In addition, seismic frame was applied to the actual non-seismic reinforced concrete school building, and the seismic performance was evaluated by nonlinear static analysis(Push-over analysis) according to the ratio of brace-height. As a result, the increase of the brace-height according to the brace-height ratio has the effect of increasing the maximum shear force and maximum load at the performance point. But the collapse of the braced frame due to the increase in the lateral stiffness occurred, indicating that seismic retrofit according to the proper brace-height is necessary. Therefore, in the seismic retrofit design of brace frame of existing school building, it is necessary to select the proper brace-height after retrofit analysis according to the brace-height ratio.

• Journal of the Korean GEO-environmental Society
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• v.12 no.3
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• pp.47-54
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• 2011

The rockfall protection fence installed to secure safety against rockfall occurring in cut slope has been designed under the condition with 50kJ of impact energy arising when the 400kg of rock block is falling from 12.5m height. However, in falling case of bigger rock block or from higher place, it is hard to be secure of safety with existing rockfall protection fence. Using the rockfall program, safety analysis for rockfall is conducted in this paper by changing slope height, separating distance from fence, and slope angle, according to rock block sizes. In the result of analysis, when a 400kg of rock block which is designed load is fallen, the existing rockfall protection fence with 2.5m height can secure most of rock fall except some cases for the slope having 20m or less hight, whereas for more than 20m height, the fallen rock is frequently splattered over the rockfall protection fence, as well as the impact energy of rockfall may exceed designed impact energy. Therefore, in the design of rock fence, it is considered appropriate to design that after conducting safety review for rockfall according to the ground conditions, evaluating the bounce height and impact energy of rock fall, and then installing appropriate rockfall protection fence would be applicable rather than just following standards based design drawing.

• Journal of Korea Entertainment Industry Association
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• v.14 no.7
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• pp.519-528
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• 2020

Purpose of this study is to analyze the changes in state anxiety, heart rate, and fall efficacy of the elderly through the handle height of walking assistant vehicle (WAV). The subjects were 32 elderlies. WAV was in the form of strollers, and it's handle height was set as 48% of a subject's total height. Also, it's height was divided into 48, 43, 38%. To measure the state anxiety, Korean State-Trait Anxiety Inventory was used and to measure the heart rate, Fitbit Charge 2 wrist heart rate monitor was used. To measure the fall efficacy, Fall Efficacy Scale-Korea was used. As the results of state anxiety and heart rate, the statistically significant increase showed continuously through the decrease of the handle height of WAV. As the results of fall efficacy, the statistically significant decrease showed continuously through the decrease of the handle height of WAV. In all of the post hoc test, the results of the state anxiety and fall efficacy showed significant difference among the each handle height of WAV and the results of the heart rate showed significant difference between the 48, 43% and 38% handle height of WAV. Thus, to decrease the state anxiety and heart rate and increase the fall efficacy of the elderly, the handle height of WAV should be properly positioned and considered to adjust to 48% of the user's total height.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.9 no.4
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• pp.165-175
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• 1997

This study qualitatively reviewed effect of the height of loading and the ratio of penetration on. the characteristics of deformation of cellular bulkhead by performing a model test of embedded steel plate cellular bulkhead which had different loading height and penetration ratio. And we also examined the effect of the loading height upon the shear behavior by performing two-dimensional model test making use of aluminum rods for a filler. Besides, test results and theoretical values based on Hansen's earth pressure theory were compared and reviewed. In consequence, it was ascertained that the yield moment of cells depended on the height of loading and the ratio of penetration, and the slip surface was located on the lower area of a cell interior according as the height of loading becomes lower. The theoretical consideration which was based on the theory of earth pressure proposed by Hansen revealed that the test results accorded with the theoretical values to some degree, and the same results were derived about the location change of the slip surface.