• Journal of Environmental Health Sciences
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• v.39 no.1
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• pp.71-82
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• 2013

Objectives: This study was performed in order to investigate hand hygiene practices among food-service businesses employees based on the awareness of hand-washing and load of indicator bacteria on their hands. It focused on the comparison of full-time and part-time workers in food-service workplaces. Methods: A direct-interview questionnaire survey and microbiological analysis were carried out with sixty workers each. Samples for microbiological analysis were collected through a modified glove-juice method from the hands of the food-service workers and were analyzed for aerobic plate count, total coliform, fecal coliform, Escherichia coli, Staphylococcus aureus, and Salmonella spp. Microbiological analysis was done according to the Food Code of Korea. Results: Significant differences (p<0.01) were found in the survey between the full-time and part-time workers in hand-washing frequency, use of hand-washing agents, and hand-drying methods. More full-time workers responded to washing their hands after preparing food, after visiting outside, after handling raw materials, and before putting on gloves/when changing gloves than did part-time workers (p<0.05). No remarkable difference was found in bacterial load on the hands except in the aerobic plate count between the two groups. The detection of E. coli, S. aureus, and Salmonella spp. on the hands of some food-service workers in both groups revealed poor hand hygiene practices. Conclusions: The results of this study indicate that there is a need for training programs in order to improve hand hygiene practices and strict hand hygiene compliance by food-service workers.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2004.04a
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• pp.239-242
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• 2004

Pilot-scale soil washing facility was developed and operation condition was determined in order to remediate a soil contaminated with As, Ni and Zn. Soil washing facility is composed of soil particle separation, soil washing and wastewater treatment process. Both oxyanionic As and cationic Ni and Zn were effciently removed using HCl rather 0than H$_2$SO$_4$ and H$_2$PO$_4$. This is why oxyanion and cation metals can be extracted simultaneously from the contaminated soil in acidic solution. Further, the contaminated soils include calcite and then demand much acidity, that is consumption of acid solution. Fine particles are enriched with contaminants, and coarse particles are removed effectively rather than fine particles. As, Ni and Zn are strongly associated with minerals, and then the residence time should be increased for a reaction with washing solution.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 1990.10a
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• pp.71-77
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• 1990

This paper describes the experimental analysis of the vibration and noise reduction for the washing machine of the home appliances. For the washing machine, the customers always feel electrical and mechanical noise and vibration. First of all, when the dehydration process is working, the washing machine has nonlinear problems and boundary conditions are varied with time. Therefore these problems are very complicated and difficult to analyze. We verify the sources of the noise and vibration and consider the countermeasure to reduce the noise and vibration level of the washing machine.

• Proceedings of the KSME Conference
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• 2003.11a
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• pp.1642-1647
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• 2003

The market of the horizontal axis washing machine (drum washing machine) has been growing drastically in Korea by about 80% annually since 2000. As market grows fast, the customerTs demands concerning quality becomes more strict and various. Imbalance sensing is a key technology to reduce the NVH problem in a washing machine, because the laundry is time-variant and uncontrollable source of imbalance, which can cause more than 200kgf exciting force. In this paper, imbalance-sensing methods are briefly reviewed, new acceleration sensing circuits are examined, and finally the control algorithm of spinning process is proposed and validated.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.04a
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• pp.337-339
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• 2003

The technology removing radionuclides from soil using soil washing was studied. The main radionuclides contaminated in the soil are Cs$^{137}$ and Co$^{60}$ . It is suitable that scrubbing time is 4 hours and a mixing ratio of soil weight and washing solution volume is 1:10. more than two times continuous scrubbing method with 0.5 M oxalic acid was needed to remove Cs$^{137}$ and Co$^{60}$ from soil more than 70%. Radionuclides removal efficiencies of recycling washing solutions recycled with strong acid resins until 5 times are similar to that of 0.5 M oxalic acid.

• Journal of agricultural medicine and community health
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• v.21 no.2
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• pp.159-171
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• 1996

It is investigated to determine the removal efficiency of organic - phosphorus insecticide residues in lettuce by washing processes, the 5 washing solution (stagnant tap water, flowing tap water, alkaline solution, acidic solution) were used with the washing time(10, 30, 50sec) and frequencies(1, 2, 3 washing, 2 rinsing). The removal efficiency of residual pesticides by 5 washing methods was increased on the more washing time and frequency, and also was the highest on the 3 times washing for each 50 sec. The removal rate with stagnant tap water was 33.7% of Diazinon, 45.7% of Dimethoate and 24.6% of Fenitrothion, but 29.4% of Diazinon, 37.7% of Dimethoate and 24.5% of Fenitrothion with flowing tap water. Therefore, the former was significantly higher effective than the latter one. The removal rate of residual pesticides with alkaline solution showed 32.1% of Diazinon, 49.5% of Dimethoate and 29.9% of Fenitrothion, and 30.4% of Diazinon, 36.4% of Dimethoate and 21.0% of Fenitrothion with acidic solution. The washing efficiency of neutral detergent showed the most effective result than others with 47.1% of Diazinon, 58.0% of Dimethoate and 39.5% of Fenitrothion. Consequently, it's appeared that the neural detergent washing was the most effective method on the 3 times washing for each 50 sec.

• Journal of Life Science
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• v.22 no.4
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• pp.565-568
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• 2012

There are various kinds of cereals used in sunsik manufacturing. Different harmful microorganisms that can contaminate these cereals have been reported. According to the different sizes of cereals used, black bean, black rice, and millet were artificially contaminated with Escherichia $Coli.$ $E.$ $coli$ contamination in cereal samples was detected after different washing steps under different conditions. The increase of washing time did not have any effect with regard to reducing $E.$ $coli$ in samples. Among several ratios between the washing solution and sample, 2:1 that have little influence to reduce $E.$ $coli$ contamination have been determined. The temperature of the washing solution is an influencing factor as well. Washing with solution at $40^{\circ}C$ could reduce 1 log of $E.$ $coli$ in samples. Among different concentrations of saline used as a washing solution, 5% could reduce 2~3 log $E.$ $coli$ in contaminated samples. However, the saline adds a salty taste to cereals when used during the washing step. To remove that, an extra washing step and large amount of washing solution are necessary in sunsik manufacturing.

• Journal of dental hygiene science
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• v.14 no.4
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• pp.537-545
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• 2014

We conducted a study to access the effectiveness of glove and washing hands for the prevention of microbial contamination during the dental clinical practice. Microbial numbers at unwashed hands and gloves were $9.938{\time}10^3(CFU)/ml$, those at washed with soap were $9.44{\time}10^3CFU/ml$ And those at washed with a typical liquid soap including disinfectant, Dettol (Reckitt Benckiser, Slough, SL1 3UH, UK) were $6.58{\time}10^2CFU/ml$. In case of unwashed hand and hand washing with soap had similar microbial numbers and in case of hand washing with Dettol showed a rapid decrease of microbial number. Hand washing with Dettol was effective to prevent microbial contamination than hand washing with soap. Also microbial numbers in all case wearing gloves decreased. It showed effectiveness of gloves for prevention of microbial contamination. In addition to microbial numbers showed a tendency to increase from 3 hours on wearing gloves, the change of new gloves after 3 hours on wearing is necessary to minimize the danger of microbial contamination.

• Fashion & Textile Research Journal
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• v.22 no.4
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• pp.534-539
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• 2020

Experimental research is needed to provide information on the removal of bloodstains since washing clothes contaminated with blood is necessary for medical related fields (such as ambulance workers and doctors) as well as for women of childbearing age. This study investigated efficient washing conditions for the removal of bloodstains with a focus on washing temperature, fiber type and blood ageing time. Polyester/cotton fabric showed the highest detergency from among three fabrics that were influenced by the composition of the fiber and the structure of the yarn and fabric. When examining the effect of detergent, it was concluded that the alkalinity over pH 10 was essential to remove bloodstains and that auxiliary agents such as soil antiredeposition agents and bleach had a significant effect on the removal of bloodstains. Washing temperature showed the highest detergency at 20℃ due to the activity of the enzyme without the denaturalization of blood. Blood-ageing influenced detergency by inducing changes in the adsorption area and chemical bond. A combination of methods such as quick removal after contamination, use of alkaline detergents including soil antiredeposition agents and bleach, and low-temperature washing could help remove bloodstains.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.8 no.2
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• pp.3-9
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• 2009

When washing machine is rotated in the laundry, it tends to lean toward one side. This tendency causes a serious vibration. The balance of washing machine plays an important role in order to reduce the vibration by injecting the sand or the salt water into the balance of washing machine. The hot plate welder is used to prevent from outflow of contents. The hot plate welder brings about many problems which is concerned with accidents. The direction recognition and location information of the balance are required in this system. In this paper, the recognition direction of balance in washing machine using machine vision system is studied. The template matching algorithm compares sub-image with original image acquired in real-time to obtain a center point of balance image. The mid points and the edges of balance are estimated by the edge detection and gauging algorithms. The data acquired by these results is used for recognition direction of balance. The automation software for image processing is developed by using LabVIEW.