• 대한의용생체공학회:의공학회지
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• 제33권4호
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• pp.184-193
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• 2012

Many studies have reported that housework done using household appliances may affect biomechanical characteristics of the musculoskeletal system. The purpose of this study was to investigate the effects of housework done using a pulsator washing machine on joints and muscles. We calculated joint torques and muscle strengths on the basis of an experimental/virtual three-dimensional motion analysis for six healthy females using the pulsator washing machine at different heights (H) and depths (D) of the inside drum (H (mm){\times}D (mm), Trial1: $962.5{\times}609.4$, Trial2: $962.5{\times}624.4$, Trial3: $982.5{\times}644.4$, Trial4: $995.5{\times}642.4$, Trial5: $1015.5{\times}677.4$). The joint torques and muscle strengths tended to be considerably different during torso flexion in the sagittal plane for all the trials. The maximum joint torques for the thoracic vertebra, left ankle, and right shoulder measured in Trial4 were significantly higher than those measured in the other trials (p < 0.05); in addition, those for the thoracic vertebra and both ankles measured in Trial5 were significantly higher than those measured in the other trials (p < 0.05). The maximum muscle strengths for the left trapezius muscle and both tibialis anterior muscles measured in Trial5 were significantly higher than those measured in the other trials (p < 0.05). These results indicate that housework done using a pulsator washing machine may affect joint torques and muscle strengths, and these effects are dependent on the height and/or depth of the inside drum of the pulsator washing machine.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1995년도 추계학술대회 논문집
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• pp.546-549
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• 1995

This paper presents a control of washing machine using ER clutch and brake actuators. After analyzing field- dependent torque of the actuators on the basis of Bingham model of the ER fluid, two sets of cylindrical ER clutch and brake are manufactured. The governing equation of motion for washing and dehydrating are derived by considering actuators' dynamics. Subsequently, PID controllers are designed to achieve desired rotational motions and tracking control results are provided to demonstrate the effectiveness of the proposed method.

• 대한기계학회논문집A
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• 제28권8호
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• pp.1212-1220
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• 2004

The structural unbalance mass and laundry are the important sources of the severe vibrations of automatic washing machines. In this paper, a mathematical model is developed for the dynamic analysis of the vertical axis automatic washing machines of pulsator-type. In the model, the rigid body motion of tub assembly is represented by six degrees of freedom and the dynamics of automatic hydraulic balancer is represented by one degree of freedom. The fundamental elastic modes of the tub shell and four suspension bars are also taken into account in the mathematical model, based on analytical and experimental modal analysis results. The 12 degrees of freedom equations of motion are derived by using the Lagrange's equations and the present dynamic model is evaluated by comparing the numerical simulation results with experimentally measured data.

• 한국지역사회생활과학회지
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• 제24권2호
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• pp.187-194
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• 2013

The purpose of this study was to define the optimal boxthorn berries washing method for developing the boxthorn berries cleaner. We analyzed the rate of removal of residual pesticides according to washing methods; 1st - habitual washing method, 2nd - drum rotation washing method, 3th - drum rotation and air bubble washing method, 4th - drum rotation and nozzle spray washing method, 5th - drum rotation and air bubble and nozzle spray washing method. A rate of removal of residual pesticides of 88% was detected in the drum rotation and air bubble and nozzle spray washing method, and a rate of 82% was detected in the habitual washing method. The drum rotation and air bubble and nozzle spray washing method appeared to be the best good washing effect compared to the habitual washing method(about 6% compared to 82.0% higher). Clothianidin Triadimefon, Triforine ingredients, the drum rotation and air bubble and nozzle spray washing method efficiency was lower compared to the habitual washing method removal efficiency.

• 한국융합학회논문지
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• 제11권10호
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• pp.237-241
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• 2020

본 연구에서는 실제형상과 같은 회전날개들을 가진 세 개의 세탁기의 모델들에 대하여 유동해석을 하였다. 회전날개의 좌측, 우측 및 바닥 평면들에 대한 압력 및 속도들에서는, 전반적으로 Model C가 유동에 대한 압력이 가장 크게 나와서 Model A에 비하여 2배 이상 나타났고, Model B와 Model A순으로 되었다. Model A, B 및 C의 회전 블레이드 측면에서의 유동의 유선속도들을 보면, 전반적으로 Model C가 유동에 대한 속도가 가장 크게 나와서 Model A에 비하여 1.7배 가량 나타났고, Model B와 Model A순으로 되었다. 회전날개의 갯수가 많다고 해서 유동상태가 양호하다기 보다 Model C와 같이 Model A나 Model B에 비하여 날개의 개수가 적지만 날개의 하부 두께가 더 두꺼운 경우가 유동 압력 및 유동 속도가 커서 세탁성능을 향상시켜 준다는 것을 알 수 있다. 또한 본 연구가 실제적으로 세탁기 회전날개의 내구성이 있는 효율적인 설계와 그 회전 날개의 미적인 융합에 적합하여 보인다.

• 한국산업보건학회지
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• 제27권2호
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• pp.115-122
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• 2017

Objectives: This study was designed to evaluate the changes in the particle filtration efficiencies of five cloth masks (4 plate types, 1 cup type) with an increasing number of machine washings and the degree of cloth expansion. Methods: NaCl aerosols were generated using an atomizer and passed through cloth masks in a dynamic aerosol chamber. Particle concentrations were measured both before and after for the cloth masks using an optical particle counter (OPC) in the size range of $0.3{\sim}10{\mu}m$. Results: In the original condition, the filtration efficiencies of the five cloth masks were A: 20.1%, B:30.9%, C: 25.0%, D: 26.5%, and E: 40.9%. As the number of washings increased in the order of one, two, and four times, the filtration efficiencies of cloth mask C increased. The filtration efficiency of A, D, and E increased after the first washing. With the exception of B, the filtration efficiency of cloth masks increased after the second washing and those of all cloth masks increased after the fourth washing. This might be caused by the fibers untangling from the yarn and being freed at one end. In this status, the packing density of the textile will not change, but the distances between fibers will increase, which might bring about an increase in filtration efficiency. When the cloth masks were extended by 10% and 20% in one direction, the filtration efficiencies of cloth masks B, D, and E decreased at 10% extension, and those of all cloth masks decreased at 20% extension. When the cloth masks were expanded by 10% and 20% in two directions, the filtration efficiencies of all cloth masks decreased by at least 34.7% at 10% extension, and by at least 60.9% at 20% extension Conclusions: The filtration efficiency of cloth masks could decrease after one to two machine washings, but will increase after four washings in comparison with their original performances. The filtration efficiency of cloth masks will decrease when they are expanded, such as when stretching over the nose during wearing status.

• 상하수도학회지
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• 제25권5호
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• pp.691-697
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• 2011

In this study, by using the Water footprint technique, the water consumption by washing machines, which holds higher ranks in using water than any other electric appliances, was analyzed during their life cycle. The life cycle is defined as raw materials production step, manufacturing step, and using step. In raw materials production step, Input materials were researched by using LCI DB(Life Cycle Inventory Database) and the water consumption was calculated with consideration of approximately 65% Input materials which were based weight. In manufacturing step, the water consumption was calculated by the amount of energy used in assembly factories and components subcontractors and emission factor of energy. In using step, referring to guidelines on carbon footprint labeling, the life cycle is applied as 5 years for a washing machine and 218 cycles for annual bounds of usage. The water and power consumption for operating was calculated by referring to posted materials on the manufacture's websites. The water consumption by nation unit was calculated with the result of water consumption by a unit of washing machine. As a result, it shows that water consumption per life cycle s 110,105 kg/unit. The water consumption of each step is 90,495 kg/unit for using, 18,603 kg for raw materials production and 1,006 kg/unit for manufacturing, which apparently shows that the using step consume the most water resource. The water consumption by nation unit is 371,269,584tons in total based on 2006, 83,385,649 tons in both steps of raw material production and manufacturing, and 287,883,935 tons in using step.

• 한국식품위생안전성학회지
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• 제25권4호
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• pp.346-353
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• 2010

본 연구는 젖소 착유농가를 대상으로 착유 및 집유 후 친환경세제를 사용하여 세척효과에 미치는 영향을 조사하기 위해 수행되었다. 착유환경이 다른 5지역의 농가를 대상으로 총 시험 기간 6주 동안 첫 3주는 기존 관행세제인 알칼리 세제와 산세제를 사용하여 착유기, 냉각기 및 착유기 라이너를 세척하였으며, 처리를 달리하여 3주는 알칼리 세제와 친환경세제를 사용하여 세척 하였다. 또한 착유기 라이너 내부를 멸균된 swab을 이용해 시계방향으로 10회 닦은 후 0.1% peptone수에 보관하였으며, 채취된 모든 샘플은 아이스박스를 이용해 보관 운반하여 잔류세균 및 잔류물질 분석을 실시하였다. 미생물 분포는 모든 지역의 착유농가에서 대장균, 대장균군, 황색포도상구균, 분내 대장균군, 녹농균 및 여시니아균이 발견되지 않았으며, 총균수는 관행세제 사용과 비교하여 차이가 없었다. 따라서 친환경세제의 세척효과는 관행세제와 비교하여 비슷한 세척효과를 나타낸 것으로 조사되었다. 세척수 잔류물질은 안성, 온양 및 천안의 젖소 착유농가의 세척수로 사용한 용수에서 질산성 질소가 기준치를 초과하였으며, 세척수의 잔류물질에서도 높은 농도를 나타냈다. 특히 원유의 특이취와 밀접한 관계가 있는 음이온계면활성제의 농도는 관행세제를 사용한 오수와 남원지역의 세척수에서 기준치보다 높은 농도를 나타냈으며, 친환경세제 사용 처리구에서는 기준치보다 낮은 결과를 나타냈다. 따라서 본 연구에서는 친환경 세제를 젖소 착유농가의 착유기 및 냉각기의 세척제로 사용하였을 때, 관행세제와 비교하여 세척효과가 비슷한 것으로 조사됐다. 또한 세척제 사용뿐만 아니라, 위생적인 착유장비 및 세척에 사용되는 용수 관리가 고품질 원유생산에 중요한 영향을 줄 것으로 생각된다.

• 복식문화연구
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• 제12권6호
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• pp.945-952
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• 2004

Shrink-resist effects and properties of the knitted fabrics from wool/acrylic(W/A) fiber blends were determined to find out an optimal blending ratio keeping the quality properties of wool products. The test fabrics were knitted by a weft knitting machine with all needle knitting structure ($0{\times}0$ rib) under the same knitting conditions with five different types of yarns: $W100\%,\;A100\%$, and W/A blended yarns(70/30, 50/50, 30/70). Shrinkage during repeated washing, electrostatic propensity, thermal resistance and pilling propensity of W/A knits. The shrink resistance was significantly enhanced on repeated washing of W/A knits, especially, over $50\%$ acrylic blended knits. Addition of strong physical force and alkali detergent applied in this washing experiment brought about superior effects with the low shrinkage rate although it was very severe washing conditions for wool fabrics. The results from the washing experiment implies that W/A blend knits can be machine washed at individual households with other ordinary laundry. There was some changes and variation found in thermal resistance, electrostatic propensity, and pilling. W/A 50/50 blended knits did not bring serious changes to other physical properties comparing with original wool, which helps consumers care wool knitted clothes more conveniently.

• 한국의류학회지
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• 제41권6호
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• pp.1050-1059
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• 2017

Drying processes often cause knitted fabrics to shrink. This study obtains proper drying conditions for in the dryer use that can minimize knitted fabric shrinkage by investigating changes in shrinkage according to drying conditions. The experiment samples were all machine washable plain, mesh, and lacoste knitted fabrics made of 100% cotton. Samples were first washed in a washing machine on a normal cycle. They were then layered on a flat surface in an artificial climate chamber and dried for 24 hours at $20^{\circ}C$ and $40^{\circ}C$, respectively. Shrinkage was measured for 180 minutes at 30 minute intervals after washing. The comparison results of the shrinkage in the washing and drying process indicate that 80.0% and 23.0% shrinkage of plain knitted and lacoste knitted fabrics occurred during the washing process. As the samples dried, the shrinkage of the plain and lacoste knitted fabrics then rapidly increased after approximately 30.0% moisture content. The highest air drying shrinkage occurred over one cycle with insignificant changes in shrinkage after repeated treatments.