• 한국의학물리학회지:의학물리
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• 제27권4호
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• pp.189-195
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• 2016

This paper aims to verify the clinical feasibility of a custom-made film created by a laser cutting tool for End-to-End (E2E) quality assurance in robotic intensity modulated radiation therapy system. The custom-made film was fabricated from the Gafchromic EBT3 film with the size of $8^{{\prime}{\prime}}{\times}10^{{\prime}{\prime}}$ using a drawing that is identical to the shape and scale of the original E2E film. The drawing was created by using a computer aided design program with the image file, which is obtained by scanning original E2E film. Beam delivery and evaluations were respectively performed with the original film and the custom-made film using fixed-cone collimator on three tracking modes: 6D skull (6DS), Xsight spine (XS), and Xsight lung (XL). The differences between total targeting errors of the original and custom-made films were recorded as 0.17 mm, 0.3 mm, and 0.17 mm at 6DS, XS, and XL tracking modes, respectively. This indicates that the custom-made film could yield nearly equivalent results to those of the original E2E film, given the uncertainties caused by distortions during film scanning and vibrations associated with film cutting. By confirming the clinical feasibility of a custom-made film for E2E testing, it can be expected that economic efficiency of the testing will increase accordingly.

• 급식외식위생학회지
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• 제2권2호
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• pp.59-66
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• 2021

The results of the inspection based on the sanitation checklist and the measurement of refrigerator/freezer temperature, illuminance, and ATP were conducted at 12 school foodservices in Daiyue-district, Taian-city, Shandong Province, China, at the same time, and the results were as follows. Five items of 'Use sterilized cutting boards', 'Use sterilized knives', 'Use worktable after sterilization', 'Use sink after sterilization', 'Sterilize the interior/exterior of the refrigerator regularly' in the checklist inspection were found not to be performed (0%). Two items of 'Disinfect hands after washing', 'Equipped with hand sterilizer' and 'Sterilize the kitchen areas regularly' were investigated as being performed only in one foodservice (8%). The average illuminance of the receiving stand were 373.08±106.35 Lux, 8% when the standard (540 Lux or higher) was complied with, the average refrigerator temperature were 7.06±0.82℃, 38.9% when the standard (-2 to 5℃) was observed 8% of cases complying with the standard (below -18℃) at -8.56±0.76℃ were investigated. As a result of ATP measurement, the surfaces of knife edge, cutting board, refrigerator door handle, worktable, and sink, which are not sterilized at all, were not suitable (accept ratio 0%), sterilized food plate (accept ratio 54.2%) and utensil for preserved food (accept ratio 75%) had a relatively high accept ratio. China's hygiene regulations should be revised in the direction of strengthening disinfection practices for facilities, equipment, and the environment, and hygiene measures such as education on disinfection and preparation of economical disinfection methods should be established.

• 한국축산식품학회지
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• 제29권6호
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• pp.695-701
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• 2009

본 연구는 축산물가공장 작업환경에 설정된 CCP의 유효성을 평가하기 위하여, 원료도체에서부터 포장에 이르는 전 공정에서 Escherichia coli를 검출하고 PFGE genotyping으로 genetic strain의 흐름을 분석하여 CCP의 적합성을 평가하였다. 시료채취를 위한 작업장은 도축장에서 냉장차량으로 원료도체를 공급받는 독립형 소규모 HACCP 가공장(100두 처리/일)과 축산물종합처리장내 HACCP 가공장(500두 처리/일)을 각각 1곳씩 선정하였다. 시료는 원료도체, 시설 및 장비(발골기, 박피기, 작업대, 벨트, 칼, 면장갑), 환경(벽, 바닥)과 작업공정상의 발골육, 부분육, 최종육을 무균적으로 채취하였다. 작업공정에서 E. coli의 높은 분리율(59.6%)과 작업환경 전반에서의 고른 검출로 E. coli가 축산물가공장 위생지표균으로의 활용 가능성을 확인할 수 있었다. 분리된 E. coli의 genotype 분포는 작업장내 미생물 오염의 흐름을 보여주었다. 소규모가공장의 경우 오염된 원료육 반입이 작업공정을 오염시키고 공정중의 교차오염 발생으로 최종육에 영향을 주었고, 축산물종합처리장내 작업장은 원료육 오염보다는 작업환경에 상존하는 오염미생물의 교차오염이 최종육에 영향을 주는 양상이었다. 따라서 포장육가공장과 같이 작업공정에 멸균처리 과정이 없는 경우는 선행요건에 해당되는 원료반입과 작업환경의 세척 및 소독이 CCP로 관리되거나 이에 준하는 특별관리가 필요하였다. 결과적으로, 작업공정에서의 E. coli 검출과 genotyping은 작업공정상의 미생물 오염의 흐름을 파악하는데 유용하였으며, 이러한 방법은 HACCP 작업장의 미생물 오염원 분석과 설정된 생물학적 critical control point의 적합성 평가에 효과적이었다.

• 농업과학연구
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• 제41권1호
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• pp.35-40
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• 2014

This study was carried out to evaluate the Salmonella cross contamination at retail chicken meat outlets in Kandy, Sri Lanka and to identify the risk factors for Salmonella contamination at retail chicken meat outlets. Fifteen retail chicken meat outlets in Kandy area were randomly selected. Pre-tested questionnaires were used to collect data for identifying risk factors of Salmonella cross contamination at retail outlets and swab samples from meat contact surfaces/utensils were obtained. Out of 57 swab samples collected from meat contact surfaces/utensils, the overall prevalence of Salmonella cross contamination was 21%. Weighing scale (33%), meat containing trays/buckets (27%) and cutting board (25%) showed the highest percentage of Salmonella prevalence whereas knife and showcase showed relatively low percentages, 14% and 9%, respectively. Retail chicken outlets with slaughtering facilities had a significantly higher prevalence of Salmonella cross contamination than those without slaughtering facilities. This higher rate of Salmonella cross contamination at retail chicken meat outlets could be attributed to lack of proper cold chains and minimal facilities, and poor level of hygiene in those outlets.

• 한국식품위생안전성학회지
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• 제15권4호
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• pp.315-323
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• 2000

국내 단체급식업체의 급식장 위생환경에 대한 기초 정보를 제공하고 단체급식에 적용할 수 있는 HACCP Plan개발시 급식장에서의 위해요소중 조리기구 및 용기, 조리종사자, 급식 작업장 등의 위해요소에 대한 정보를 제공하기 위하여 미생물학적인 분석이 실시되었다. 도마의 위생상태는 육류, 야채 및 생선용의 도마종류별 및 급식장별 차이가 있었으나 일반적으로 일반세균수가 검체 채취면적 10$\times$10 $ extrm{cm}^2$당 $10^2$~$10^4$ CFU 정도로 양호하였으며, 소독한 행주의 경우 일반세균은 상당히 낮았고 대장균균은 검출되지 않아 양호하였다. 반면 채와 탈피기 등의 조리기구는 기구별, 급식장별 및 분석횟수별로 차이는 있으나 일반세균이 $10^{6}$ CFU이상 검출되거나 대장균군도 $10^{6}$ CFU이상 검출된 곳도 있어 전반적으로 위생상태가 좋지 않았으며, 특히 칼의 경우 오염된 소독용액에 의한 이차오염이 문제되었다. 이러한 오염된 전처리기구는 원부재료를 전처리할 때 교차 오염시킬 수 있어 항상 세심한 주의와 관리.운영이 필요할 것으로 보인다. 조리종사자의 손에 대한 분석 결과 1차에서 $10^4$ CFU 이하의 일반세균 및 대장균관이 일부에서 검출되었으나 2차 및 3차 측정시 점차 줄어드는 경향을 보였으며 황색포도상구균은 전혀 검출되지 않았다. 급식환경의 위생관리실태를 파악하기 위한 공중낙하균을 측정한 결과 작업장의 경우 일반세균수는 모든 급식장에서 7 CFU/Plate 이하로 검출되었고 공중낙하 황색포도상구균은 단 1곳의 측정지점에서만 검출되었다.

• 한국식품과학회지
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• 제36권1호
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• pp.174-182
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• 2004

Hygienic standards for pizza specialty restaurant located in Seoul during summer, 2000 were established based on HACCP concept by measuring temperature, time, pH, $A_{w}$ and microbiological assessments of pizza, and evaluation of hygienic conditions of kitchens and workers. Kitchen and worker conditions were average 1.2 and 1.0 (3 point Sly's scale), respectively, Microbial contaminations occurred at $5-60^{\circ}C$, pH above 5.0, and $A_{w}$ (0.93-0.98). Microbial assessments for pizza processing revealed $1.5{\times}10^{2}-3.9{\times}10^{8}\;CFU/g$ of TPC and $0.5{\times}10^{1}-1.6{\times}10^{7}\;CFU/g$ of coliforms, exceeding standards ($TPC\;10^{6}\;CFU/g\;and\;coliform\;10^{3}\;CFU/g$) established by Solberg et al., although significantly decreased after baking. S. aureus was not discovered, but Salmonella was found in onions. Tools and containers such as pizza cutting knife, topping container, serving bowl, pizza plate, working board, and dough kneading board contained $6.2{\times}10^{2}-1.1{\times}10^{9}\;CFU/g$ of TPC, $2.0{\times}10^{1}-6.2{\times}10^{3}\;CFU/g$ of coliforms. Workers' hands contained $3.1{\times}10^{4}\;CFU/g$ of TPC and S. aureus as compared to safety standards of Harrigan and McCance (500 and 10 CFU/g of TPC and coliforms per $100cm^{2}$). CCPs (critical control points) were determined as receiving, topping, and baking according to CCP decision tree analysis. Results suggest purchase of quality materials, careful monitoring of time and temperature, hygienic use of tools and utensils, and sanitary practicer by workers are recommended as control points for safe pizza production.

• 대한영양사협회학술지
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• 제17권2호
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• pp.142-160
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• 2011

The purpose of this study was to investigate food sanitation status in elderly welfare facilities and assess the performance of food sanitation practices. Twenty elderly welfare facilities out of 85 located in Seoul with a capacity of fewer than 50 persons participated. The food sanitation status of worktable, kitchen utensils (knives, cutting boards, ladles, spoons), and tableware and bowls were examined by ATP bioluminescence. The results found that the ATP value of knife was the highest. Those of ladles appeared relatively higher than others. Meanwhile, the tableware and bowls, although washed everyday after meals, had the lowest ATP value. This study also conducted a survey on the food sanitation practices of 32 cooking employees in the 20 facilities. Fifty-six percent were in their 40s, and 53% had graduated from high school. More than half (66%) of them had no certification of cooking. Half of the respondents had worked for at least 5 years in food service facilities, and had received food sanitation training. Among them, 31% said they applied food sanitation training while working, and 47% responded the training was very helpful. The foodservice employees demonstrated good food sanitation practices. The results show that food sanitation performance of the workers significantly differed according to their age, education level, total work experience in food service facilities, chef certification, and prior food sanitation experience.

• Journal of the Korean Wood Science and Technology
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• 제24권1호
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• pp.75-80
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• 1996

The purpose of this study is to clarify the mechanism of moisture transfer depend on the thickness of the spruce(Picea sitchensis Carr.). Therefore, as the basic research of moisture transmission, the amount of moisture transmission and the moisture distribution in specimens and temperature of it's surfaces in vapor transmission process were investigated. The experiment was conducted in a steady state. and the moisture distribution was measured by knife cutting and weighing the specimens. The following conclusions were obtained ; 1. It can be found that distribution of moisture in the specimen can be approximated by two different straight lines intersecting at nine or ten percent moisture content. The amount of moisture movement defends on the gradient of moisture in the wood. 2. It is investigated that the wood surface moisture contents(MCs) are less for thinner specimens than for thick ones on the absorption side. On the other hand, the wood surface MCs are greater for thinner specimens than for thick ones on the desorption side. The main factor that affects the EMC of wood would be temperature when the relative humidity of atmosphere is constant. The specimen generate heat with the absorption and desorption process. In addition, the velocities of moisture transmission varied with the thicknesses of specimens. If the temperature of wood becomes greater, its MC decreases. Then the difference between surface MC and EMC of adsorption and desorption side becomes greater for thinner specimens. Therefore it is considered that the coefficients of moisture transfer decreases with the increases of the specimens' thicknesses.

• Advances in materials Research
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• 제13권3호
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• pp.183-194
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• 2024

D3 tools steel and 440C stainless steel (SS) are normally being employed for application such as knife blade and cutting tools. These steels are iron alloys which have high carbon and high chromium content. In this study, lab work focused on the microstructural and corrosion behavior of D3 tools steel and 440C SS after went through heat treatment processes. Heat treatments for both steels were started with normalizing at 1020 ℃, continue with hardening at 1000 ℃followed by oil quenching. Cryogenic treatment was carried out in liquid nitrogen for 24 hours. The addition of cryogenic heat treatment is believed to increase the hardness and corrosion resistance for steels. Both samples were then tempered at two different tempering temperatures, 160 ℃ and 426 ℃. For corrosion test, the samples were immersed in NaCl solution for 30 days to study the corrosion behavior of D3 tool steel and 440C SS after heat treatment. The mechanical properties of these steels have been investigated using Rockwell hardness machine before heat treatment, after heat treatment (before corrosion) and after corrosion test. Microstructure observation of samples was carried out by scanning electron microscopy. The corrosion rate of these steels was calculated after the corrosion test completed. From the results, the highest hardness is observed for D3 tool steel which tempered at 160 ℃(54.1 HRC). In terms of microstructural analysis, primary carbide and pearlite in the as-received samples transform to tempered martensite and cementite after heat treatment process. From this research, for corrosion test, heat treated 440C SS sample tempered with 426 ℃possessed the excellent corrosion resistance with corrosion rate 0.2808 mm/year.

• Composites Research
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• 제21권5호
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• pp.23-30
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• 2008

칼이나 송곳 같이 날카로운 날이 있거나 같이 뽀족한 도구를 사용한 위협을 군인 뿐 아니라 경찰이나 경호원들에게 쉽게 일어날 수 있다. 이러한 위협으로부터 보호하기 위한 방호복의 소재의 적용하기 위해 방탄소재로 사용되는 Kevlar 직물을 사용하였으며 방검 및 방침 특성 향상을 위해 나노입자가 충진된 전단농화유체(Shear thickening fluid)를 함침하였다. National Institute of Justice 시험 격에 따라 송곳과 칼을 제작하여 낙하충격시험기를 사용한 방검 및 방침특성 평가시험을 수행하였다. 전단농화유체는 각각 100nm, 300nm, 500nm 기의 구형 나노 $SiO_2$ 입자를 충진시켜 제작하였으며 전단농화유체의 함침과 나노 입자의 크기가 갖는 방검 및 방침 특성에 대한 영향력을 평가하였다. STF를 함침한 Kevlar 직물은 송곳을 사용한 낙하충격시험에서는 미처리 직물에 비해 좀 더 높은 충격하중을 지지하며 견고히 송곳의 침투에 저항하는 우수한 방침 특성을 보여준 반면 칼을 사용한 방검시험에서는 효과를 보여주지 못하였다. 특히 전단농화유체를 구성하는 나노입자의 크기는 방침 특성을 결정하는 주요한 인자임을 확인하였다.