• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2006년도 춘계학술대회 논문집
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• pp.127-131
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• 2006

There are being a lot of studies for achievement of high speed Dehydration, high-strength and Lightweight of washing machine in the latest washing machine business. It is essential that Press-joining Strength of Spin Drum Seaming division is improved .to attain that target. Generally, we are using Mechanical press-joining by Seaming and T.I.G (Tungsten Inert Gas) welding among part joint method. Mechanical press-joining method that is mainly using for Stainless Steel (STS430) Drum have lots of merit that consumption of energy is low more than welding and production costs cut down and generation of the corrosion is solved by removing weld zone defect and materials having different properties are enable to join without special equipment. But, it is difficult to realize joint strength required at high speed operation because joint strength of mechanical press-joining method is low remarkably in comparison with welding. Also, there are a lot of analysis difficulties and very limited research is under way due to the dynamic factor such as multistage plastic working, elastic recovery, residual stress etc. The results of this study show optimal joining condition for mechanical press-joining by performing lots of tensile joining strength test with various specimen under multi-change of important design factor such as seaming width, bead area and bead depth etc.

• 한국식품저장유통학회지
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• 제6권3호
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• pp.319-323
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• 1999

본 연구는 키위를 이용하여 새로운 가공식품을 개발하고자 삼투건조로 전처리하여 열풍, 진공, 동결건조한 후 삼투처리 유무에 따라 각각의 품질특성을 비교 평가하였다. 수분함량은 무처리 및 삼투처리한 키위를 열풍 진공, 동결건조 하였을 때 무처리가 삼투처리한 경우 보다 낮았다. 건조방법에 따른 vitamin C의 함량은 무처리보다 삼투처리가 낮았으며 건조시간에 따른 vitamin C의 함량변화는 동결, 진공건조시 완만한 감소를 보이는 반면 열풍건조한 경우는 많은 감소를 보였다. 수분의 이동을 나타내는 확산속도는 무처리의 경우 열풍건조가 가장 빨랐으나 삼투처리 후에는 진공건조가 가장 빠르게 나타났다. 세 가지 건조방법 모두 삼투처리가 빠른 건조 양상을 보여 효과적인 전처리 방법임을 확인 할 수 있었다. 품질변화 특성은 열풍, 진공 동결건조 모두 2차 반응속도식이 품질변화예측 모델식으로 적합한 것으로 나타났다.

• Asian-Australasian Journal of Animal Sciences
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• 제28권6호
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• pp.807-815
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• 2015

The present study aimed at evaluating the intensity of Tifton 85 conditioning using a mower conditioner with free-swinging flail fingers and storage times on dehydration curve, fungi presence, nutritional value and in vitro digestibility of Tifton 85 bermudagrass hay dry matter (DM). The dehydration curve was determined in the whole plant for ten times until the baling. The zero time corresponded to the plant before cutting, which occurred at 11:00 and the other collections were carried out at 8:00, 10:00, 14:00, and 16:00. The experimental design was randomised blocks with two intensities of conditioning (high and low) and ten sampling times, with five replications. The high and low intensities related to adjusting the deflector plate of the free iron fingers (8 and 18 cm). In order to determine gas exchanges during Tifton 85 bermudagrass dehydration, there were evaluations of mature leaves, which were placed in the upper middle third of each branch before the cutting, at every hour for 4 hours. A portable gas analyser was used by an infrared IRGA (6400xt). The analysed variables were photosynthesis (A), stomatal conductance (gs), internal $CO_2$ concentration (Ci), transpiration (T), water use efficiency (WUE), and intrinsic water use efficiency (WUEi). In the second part of this study, the nutritional value of Tifton 85 hay was evaluated, so randomised blocks were designed in a split plot through time, with two treatments placed in the following plots: high and low intensity of cutting and five different time points as subplots: cutting (additional treatment), baling and after 30, 60, and 90 days of storage. Subsequently, fungi that were in green plants as well as hay were determined and samples were collected from the grass at the cutting period, during baling, and after 30, 60, and 90 days of storage. It was observed that Tifton 85 bermudagrass dehydration occurred within 49 hours, so this was considered the best time for drying hay. Gas exchanges were more intense before cutting, although after cutting they decreased until ceasing within 4 hours. The lowest values of acid detergent insoluble nitrogen were obtained with low conditioning intensity after 30 days of storage, 64.8 g/kg DM. The in vitro dry matter of Tifton 85 bermudagrass did not differ among the storage times or the conditioning intensities. There was no fungi present in the samples collected during the storage period up to 90 days after dehydration, with less than 30 colony forming units found on plate counting. The use of mower conditioners in different intensities of injury did not speed up the dehydration time of Tifton 85.

• 한국자기공명학회논문지
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• 제1권1호
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• pp.45-58
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• 1997

Heteropoly compounds, H3PMo12O40, CsxH3-xPMo12O40, and vanadium containing heteropoly compound were characterized by Solid-state broad line 1H MAS NMR, 31P MAS NMR, and High Speed MAS 51V NMR spectroscopy of quadrupolar nuclei. The effects of calcination, dehydration, and the number of protons on the structure of heteropoly compounds were studied. The results of this study demonstrate that these Solid-state NMR techniques are very useful tools to study heteropoly compounds.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2012년도 추계 학술논문 발표대회
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• pp.263-264
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• 2012

In this study, the ultra high strength concrete which have 100, 150, 200MPa took the heat from 20℃ to 70 0℃ and the 0, 20% stress in normal condition's to evaluate stress-strain, residual compressive strength and thermal expansion deformation were evaluated. The heating speed of specimen was 0.77℃/min 20~50℃, 50℃ before the target temperature, and the other interval's heating speed was 1℃/min. As a result, the stress-strain curve of non-load specimen showed the liner behavior at high temperature when the specimen's strength increased more. If ultra high strength concrete got loads, its compressive strength tended to decrease different from the normal strength concrete. The thermal expansion deformation was expanded from a vitrification of quartz over 500℃. however, over the 600℃, it was shrinked because of the dehydration of the combined water.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2013년도 추계 학술논문 발표대회
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• pp.34-35
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• 2013

In this study, the ultra high strength concrete which have 80, 130, 180MPa took the heat from 20℃ to 700℃ and the 0, 20% stress in normal condition's to evaluate stress-strain, residual compressive strength and thermal expansion deformation were evaluated. The heating speed of specimen was 0.77℃/min 20~50℃, 50℃ before the target temperature, and the other interval's heating speed was 1℃/min. As a result, the stress-strain curve of non-load specimen showed the liner behavior at high temperature when the specimen's strength increased more. If ultra high strength concrete got loads, its compressive strength tended to decrease different from the normal strength concrete. The thermal expansion deformation was expanded from a vitrification of quartz over 500℃. however, over the 600℃, it was shrinked because of the dehydration of the combined water.

• 한국가시화정보학회지
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• 제8권4호
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• pp.48-53
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• 2010

Water-uptake through roots, is an essential process of the water flow in plants. Its visualization is very useful for understanding sap flow dynamics at whole plant level. In this study, the tips of Arabidopsis' root hairs were excised and exposed to repeated dehydration and rehydration processes. The water-refilling through individual xylem vessels was visualized using the synchrotron X-ray micro-imaging technique. The high temporal resolution ($2\;{\mu}m$) and beam intensity of the X-ray source allowed to acquisition of consecutive X-ray images of the water-refilling process up to 10 frames/sec. Various flow patterns were observed and the ascending speed of the water-air interfaces was analyzed. The relation between the water-rising height and ascending speed was also analyzed. The present results would provide better alternative for investigating sap flows in roots.

• 한국정밀공학회지
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• 제23권8호
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• pp.154-162
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• 2006

By laying its drum horizontally, front-loaded washing machine mostly used in Europe that uses the head of the water to launder was appropriate for washing only small amount of laundry. However, the demands of customers are requiring front-loaded washing machine to handle big capacity laundry as well, and have faster rotation speed to increase drying ability. To meet such demands, more stress from bending and twisting are complexly loaded onto the shaft supporting the horizontal drum, causing problems in fracture strength and fatigue life. Shafting system is mainly divided into flange and shaft. Flange is located between the drum and shaft, transferring power from the shaft to drum, and acting as a supporter of the back of the drum. Shaft is connected from the flange to insert production, transferring power from the motor to drum, and mainly acting as stiffness against the horizontal weight of the shafting system. In this paper, strength analysis and experiment were executed on both the shaft and flange of front-loaded washing machine to suggest the design improvement of shafting system for big capacity, high-rotation drying. Also, verification of this evaluation was executed on fracture strength and fatigue life for studied shaft system.

• 한국정밀공학회지
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• 제25권1호
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• pp.99-107
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• 2008

There are being a lot of studies for achievement of high speed Dehydration, high-strength and Lightweight of washing machine in the latest washing machine business. It is essential that strength of mechanical press-Joining (MPJ) for spin drum is improved to attain that target. MPJ of spin drum is composed of seaming and caulking process. Because Seaming process of MPJ has various design factors such as thickness, bending radius, seaming width, caulking press width and the dynamic factor such as multistage plastic working, elastic recovery, residual stress, the optimum conditions can't be easily determined. Using a design of experiment (DOE) based on the FEM (Finite Element Method), which has several advantages such as less computing, high accuracy performance and usefulness, this study was performed investigating the interaction effect between the various design factor as well as the main effect of the each design factor during drum MPJ and proposed optimum condition using center composition method among response surface derived from regression equation of simulation-based DOE.

• 대한환경공학회지
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• 제30권8호
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• pp.839-846
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• 2008

탈수된 케이크의 함수율을 저감하기 위하여 폴리아크릴아마이드계 고분자 응집제의 응집특성을 평가하였다. 하수 슬러지의 탈수효율은 응집제의 종류, 교반 속도 및 시간, 용해수의 농도 등에 관계된 두드러진 영향이 있음을 알게 되었다. 최적 교반 속도 및 시간은 실험조건에서 각각 700 rpm 및 3초이었다. 탈수효율은 700 rpm까지는 비례적으로 증가하였다. 응집제의 용해수로 재이용수를 사용하였을 때, 모든 종류의 용해점도는 감소되었다. 그러나 그 점도 변화는 각 응집제의 탈수효율과 비례하지는 않았다. 1차 및 2차 응집반응의 조합으로 한가지 응집제를 사용한 응집 시스템을 평가하였다. 2단 응집공정의 1차 및 2차 투입량 비율의 탈수효율에 대한 영향 또한 평가하였다. 2단 응집 시스템의 최적 조건은 저 및 고점도 응집제에 각각에 대하여 총투입량 대비 1차 투입량이 75%와 50%이었다. 그 결과를 기초로, 2단 응집의 전체 메커니즘을 제안하였으며, 이러한 방법으로 응집 공정들을 최적화함으로써 비용 절감이 가능함을 예상할 수 있었다.