• Title/Summary/Keyword: reliability and safety

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International Tendencies for Estavlishing a Microbiogical Standard for Food (식품의 미생물 규격기준의 국제적동향)

  • 신광순
    • Journal of Food Hygiene and Safety
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    • v.1 no.1
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    • pp.77-95
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    • 1986
  • In 1962 the governing bodies of FAO and WHO approved the establishment of a joint FAO/WHO Food Standards Programme, the creation of a jointly sponsored body to be known as the Codex Alimentarius commission to implement the Programme. It can reasonably be claimed that the Commission has assumad the leading role in establishing internation food standards throughout the world. The Codex Committee of Food Hygiene has received much advice and assistance from other international organization which have been working in this field for a number of years. In particular, it has received valuable background documentation from the International Commission on Microbiological Specifications for Foods(ICMSF) which was set up by the International Association of Microbiological Societies(IAMS), and also from the International Organization for Standardization (ISO). Nevertheless, in spite of the information supplied by governments and research bodies in this field, microbiological standards have proved to be a highly controversial subject from the point of view of Codex standards. When it is decided to establish a microbiological standard for a food or class of foods, the following technical and administrative aspects must be considered: 1) The standard should be based on factual studies and serve one or more of the following objectives: (1) to determine the conditions of hygiene under which the food should be manufactured; (2) to minimize the hazards to public health; (3) to measure the keeping quality and storage potential of the food 2) The standard should be attainable under practicable operating and commercial conditions and should not entail the use of excessive heat treatment or the additions of extra preservatives. 3) The standard should be determined after investigation of the processing operation. 4) The standard should be as simple and inexpensive to administer as possible, the number of tests being kept to a minimum. 5) Details of methods to be used for sampling, examining and reporting should accompany all published microbiological standards. 6) In establishing tolerance levels for the permissible number of defective samples, allowance should be made for sampling and other variations due to differences in the laboratory methods. The following additional points should be kept in mind: 1) It is not satisfactory to establish one set of microbiological standards for a miscellaneous group of foods, such as“frozen foods”or“precooked foods”. 2) Microbiological standards should be applied first to the more hazardous types of food on the basis of experience of expected microbiological levels, taking into account variations in composition, processing procedures, and storage. 3) When a standard is established, there should be a definite relationship between the standard and the hazard against which it is meant to protect the public. 4) The sensitivity, reliability, and reproducibility of the sampling and analytical methods should be compared in different laboratories and the methods to be used should be specified in detail as part of the standard. 5) Tolerances should be included in the standard to account for inaccuracies of sampling and analysis. 6) Standards should be applied on a voluntary basis before compliance is made mandatory.

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Investigation of Water-Soluble Vitamin (B1, B2, and B3) Contents in Rice, Noodles, and Sauces (밥, 면, 소스류에 존재하는 수용성 비타민 B1, B2 그리고 B3 함량 검토)

  • Cho, Jin-Ju;Hong, Seong Jun;Boo, Chang Guk;Shin, Eui-Cheol
    • Journal of Food Hygiene and Safety
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    • v.35 no.4
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    • pp.398-410
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    • 2020
  • In this study, the contents of soluble vitamins B1 (thiamin), B2 (riboflavin), and B3 (niacin) in 13 kinds of rice, 11 kinds of noodles, and 15 kinds of sauces were identified. The limit of detection (LOD) and limit of quantification (LOQ) were checked to determine the reliability of the experimental results, and the accuracy of the results through the standard reference material (SRM 1849a) was verified to show excellent indicators. As for thiamin, japchaebab (stir-fried glass noodles with rice) was found to contain the highest content among rice dishes, makguksu (buckwheat noodles) among noodle dishes, and tomato spaghetti sauce among sauces. Riboflavin was identified as having the highest content in slightly spicy jajangbab (black-bean sauce with rice), bibimguksu (spicy noodles) for noodles, and spicy curry with turmeric for sauces. Niacin was highest in content in the deep and rich flavors of spicy chicken-fried rice, janchiguksu (banquet noodles), and black-bean sauce, respectively. As a result of checking the amount of recommended daily intake of water-soluble vitamins for Korean adult men and women, the highest content of riboflavin was 217.40% for men and 271.75% for women. Through this study, we are going to establish a database of nutrients for the water-soluble vitamins contained in rice, noodles, and sauces to provide the necessary dietary data concerning the content of the water-soluble vitamins contained in foods for daily recommended intake.

Multiple-image Encryption and Multiplexing Using a Modified Gerchberg-Saxton Algorithm in Fresnel-transform Domain and Computational Ghost Imaging

  • Peiming Zhang;Yahui Su;Yiqiang Zhang;Leihong Zhang;Runchu Xu;Kaimin Wang;Dawei Zhang
    • Current Optics and Photonics
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    • v.7 no.4
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    • pp.362-377
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    • 2023
  • Optical information processing technology is characterized by high speed and parallelism, and the light features short wavelength and large information capacity; At the same time, it has various attributes including amplitude, phase, wavelength and polarization, and is a carrier of multi-dimensional information. Therefore, optical encryption is of great significance in the field of information security transmission, and is widely used in the field of image encryption. For multi-image encryption, this paper proposes a multi-image encryption algorithm based on a modified Gerchberg-Saxton algorithm (MGSA) in the Fresnel-transform domain and computational ghost imaging. First, MGSA is used to realize "one code, one key"; Second, phase function superposition and normalization are used to reduce the amount of ciphertext transmission; Finally, computational ghost imaging is used to improve the security of the whole encryption system. This method can encrypt multiple images simultaneously with high efficiency, simple calculation, safety and reliability, and less data transmission. The encryption effect of the method is evaluated by using correlation coefficient and structural similarity, and the effectiveness and security of the method are verified by simulation experiments.

Effects of Kalopanax Pictus Extracts and Their Related Origin on Gastric Lesions (해동피 및 유사생약 추출물의 위 손상에 대한 효과)

  • Hwang, In Young;Hwang, Seon A;Jeong, Choon Sik
    • Journal of Food Hygiene and Safety
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    • v.28 no.4
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    • pp.367-375
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    • 2013
  • Kalopanax pictus has pharmacologically anti-inflammatory and analgesic effect and is known to respond to treatment of backache, knee pain and etc. In this study, we investigated the effects on gastric lesions of Kalopanax pictus both from Korea (KPK) and China (KPC) compared with their related origin, Znthoxylum ailanthoide both from Korea (ZAK) and China (ZAC), and Korean Bombax malabaricum (BMK). In preliminary screening, KPK and KPC shown effective inhibition of HCI EtOH-induced gastritis in rats. To elucidate their protective effects on gastric lesions, we assessed inhibition of H. pylori colonization, 2,2-diphenyl-1-picrylhydrazyl(DPPH) radical scavenging activities, reducing power test, and inhibition of lipid peroxidation. KPK was the most effective from antioxidant assays. KPK also shown the inhibition of indomethacin-induced gastric ulcer in rats. Gastric secretion in rats, KPK reduced the secretion of gastric juice and total acidity and raised pH. Therefore, it is possible that KPK can be developed as health functional food and natural medicine. In addition, it can contribute to the standardization with objectivity and reliability for KPK through the criteria establishment of the precise origin of medicine, the prevention of indiscriminate distribution of imitation, and the rising rate of dependence on imports of medicinal herbs, and mixing prevention of low-quality goods.

A Study on the Influencing Factors of the Sales and Surplus Companies of the Townbuses in Seoul (서울시 마을버스 매출액 및 흑자업체의 영향요인에 대한 연구)

  • Jang, Jae-min;Shin, Sung-il;YI, Yong-ju
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.21 no.4
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    • pp.115-124
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    • 2022
  • Unlike the semi-public system of city buses, Seoul's townbus are operated on a private operating system, which is poor condition to the changes in the environment. Sales decreased due to a decrease in the number of passengers due to COVID-19 and a demand for conversion due to the advent of competitive transportation methods, and the financial support of Seoul Metropolitan Government is continuously increasing. In this study, to analyze the characteristics of townbus operated by a private operating system, the townbus sales and surplus companies were analyzed by what factors were affected. For the analysis data, townbus financial statements of Seoul in 2018 were used, and townbus sales and surplus companies were applied as dependent variables, and townbus operation system, satisfaction survey, humanities and social variables, and subway and public bicycle characteristics were applied as independent variables. As a result of the analysis, the sales is affected by operating hours per vehicle, in-vehicle safety, the number of households, the number of elderly people, and public bicycle variables, and surplus companies are affected by in-vehicle safety, reliability, and public bicycle variables. In particular, public bicycles, a competitive means of transportation, had an impact on industry sales, and the townbus business environment is expected to become more difficult as time goes by. The industry is seeking self-rescue measures, and Seoul is required to strengthen financial support so that townbus can operate stably.

Stochastic analysis for uncertain deformation of foundations in permafrost regions

  • Wang, Tao;Zhou, Guoqing;Wang, Jianzhou;Zhao, Xiaodong;Yin, Leijian
    • Geomechanics and Engineering
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    • v.14 no.6
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    • pp.589-600
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    • 2018
  • For foundations in permafrost regions, the displacement characteristics are uncertain because of the randomness of temperature characteristics and mechanical parameters, which make the structural system have an unexpected deviation and unpredictability. It will affect the safety of design and construction. In this paper, we consider the randomness of temperature characteristics and mechanical parameters. A stochastic analysis model for the uncertain displacement characteristic of foundations is presented, and the stochastic coupling program is compiled by Matrix Laboratory (MATLAB) software. The stochastic displacement fields of an embankment in a permafrost region are obtained and analyzed by Neumann stochastic finite element method (NSFEM). The results provide a new way to predict the deformation characteristics of foundations in permafrost regions, and it shows that the stochastic temperature has a different influence on the stochastic lateral displacement and vertical displacement. Construction disturbance and climate warming lead to three different stages for the mean settlement of characteristic points. For the stochastic settlement characteristic, the standard deviation increases with time, which imply that the results of conventional deterministic analysis may be far from the true value. These results can improve our understanding of the stochastic deformation fields of embankments and provide a theoretical basis for engineering reliability analysis and design in permafrost regions.

FMECA Procedure for Failure Analysis of Train High-Speed Circuit Breaker (전동차 고속차단기 고장 분석을 위한 FMECA 기법)

  • Kim, Sung-Ryeol;Moon, Yong-Sun;Choi, Kyu-Hyoung
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.16 no.5
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    • pp.3370-3377
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    • 2015
  • FMECA(Failure Mode, Effects and Criticality Analysis) techniques to make quantitative evaluation of failure effects severity and criticality have been applied to systematic failure analysis for reliability improvement of train which should provide regular service and secure high level of safety as a mass transportation system. These FMECA techniques do not fully reflect the inherent train operation and maintenance circumstances because they are based on the FMECA standards devised for other industries such as automobile industry and FMECA standard dedicated to train industry has not been established yet. This paper analyzes FMECA standards for various industries, and suggests a FMECA technique dedicated to train industry which makes failure effect analysis and criticality analysis step by step and makes criticality analysis placing emphasis on the severity of the failure effect. The proposed technique is applied to FMECA of high-speed current breaker which is a core safety device of train using field failure data for 15 years of train maintenance. The FMECA results show that breakage of arc chute has the highest risk with 3rd severity class and 5th criticality class among all the components of high-speed circuit breaker. Damage and poor contact of electronic valve, and cylinder breakage with 3rd severity class and 4th criticality class are followed by. These results can be applied to improvement of design and maintenance process for high-speed circuit breaker of train.

Risk Analysis for the Rotorcraft Landing System Using Comparative Models Based on Fuzzy (퍼지 기반 다양한 모델을 이용한 회전익 항공기 착륙장치의 위험 우선순위 평가)

  • Na, Seong Hyeon;Lee, Gwang Eun;Koo, Jeong Mo
    • Journal of the Korean Society of Safety
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    • v.36 no.2
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    • pp.49-57
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    • 2021
  • In the case of military supplies, any potential failure and causes of failures must be considered. This study is aimed at examining the failure modes of a rotorcraft landing system to identify the priority items. Failure mode and effects analysis (FMEA) is applied to the rotorcraft landing system. In general, the FMEA is used to evaluate the reliability in engineering fields. Three elements, specifically, the severity, occurrence, and detectability are used to evaluate the failure modes. The risk priority number (RPN) can be obtained by multiplying the scores or the risk levels pertaining to severity, occurrence, and detectability. In this study, different weights of the three elements are considered for the RPN assessment to implement the FMEA. Furthermore, the FMEA is implemented using a fuzzy rule base, similarity aggregation model (SAM), and grey theory model (GTM) to perform a comparative analysis. The same input data are used for all models to enable a fair comparison. The FMEA is applied to military supplies by considering methodological issues. In general, the fuzzy theory is based on a hypothesis regarding the likelihood of the conversion of the crisp value to the fuzzy input. Fuzzy FMEA is the basic method to obtain the fuzzy RPN. The three elements of the FMEA are used as five linguistic terms. The membership functions as triangular fuzzy sets are the simplest models defined by the three elements. In addition, a fuzzy set is described using a membership function mapping the elements to the intervals 0 and 1. The fuzzy rule base is designed to identify the failure modes according to the expert knowledge. The IF-THEN criterion of the fuzzy rule base is formulated to convert a fuzzy input into a fuzzy output. The total number of rules is 125 in the fuzzy rule base. The SAM expresses the judgment corresponding to the individual experiences of the experts performing FMEA as weights. Implementing the SAM is of significance when operating fuzzy sets regarding the expert opinion and can confirm the concurrence of expert opinion. The GTM can perform defuzzification to obtain a crisp value from a fuzzy membership function and determine the priorities by considering the degree of relation and the form of a matrix and weights for the severity, occurrence, and detectability. The proposed models prioritize the failure modes of the rotorcraft landing system. The conventional FMEA and fuzzy rule base can set the same priorities. SAM and GTM can set different priorities with objectivity through weight setting.

Establishment of accreditation criteria for nutrition and dietary education materials (영양.식생활 교육자료의 인증 심사기준 개발 연구)

  • Lee, Kyoung Ae;Kim, Ji-Myung;Park, Yoo Kyoung;Lee, Kyung-Hea;Oh, Sang Woo;Lee, Hee Seung
    • Journal of Nutrition and Health
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    • v.46 no.5
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    • pp.470-481
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    • 2013
  • This study provides standardized scientific criteria for education materials on nutrition and diet that could be used in schools, workplaces, and health and medical facilities. The study was conducted from April 2011 to October 2011. Literature reviews, institutional visits, and telephone interviews were conducted for the first draft of the accreditation criteria. Expert meeting and advisory councils were conducted in order to obtain feedback after development of the first draft of accreditation criteria. In order to verify the validity and reliability of the first draft on certification criteria, a survey was sent out to 143 professionals, including professors, researchers, health and medical experts, teachers, nutrition teachers, dietitians, and clinical nutritionists. After several modifications, the final accreditation criteria were established for 1) printed materials (authority, credibility, objectivity, organization, editing, real-life usability, activities and participation, and public interest), 2) web-sites (authority, credibility, objectivity, design, real-life usability, accessibility, currency, and public interest) and 3) materials with activities (credibility, organization, design, convenience of utilizing, safety, and public interest). Out of several criteria, contents (authority, credibility. and objectivity) and publicity (public interest) areas are mandatory requirements. For the accreditation, books for learning and materials with activities are required to meet more than six evaluation components, and the other materials are required to meet more than five evaluation components, including the required area. Accreditation criteria developed in this study could be used as a standard for development or selection of good education materials for nutrition and dietary life.

Assessment and Improvement of Documentation Status on the Statements for the Sea Area Utilization Consultation according to the Project of Ports and Fishery Harbors (항만·어항개발사업의 해역이용협의서 작성실태 평가 및 개선방안)

  • Tac, Dae-Ho;Oh, Hyun-Taik;Kim, Gui-Young;Lee, Dae-In
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.21 no.4
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    • pp.361-371
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    • 2015
  • This study analyzed the 91 cases of the statements for the Sea Area Utilization Consultation according to the developmental projects of ports and fishery harbors for 2012 2014 and the status of the record of document, and suggested the improvement way to go. The marine environmental timpact assessment items both marine chemistry such as water quality, sediment and marine biology such as benthic animal, plankton, and fisheries show highly rate of site survey. But, the utilization of those data through site survey is too low, and it is necessary to adopt the QA/QC for the reliability of survey data. The items of marine physics such as tide, tidal current analyzed based on references not a site survey. However, the simulation performed actively without calibration and verification compared to the result of site survey. When the projects of port and fishery harbor perform, it is necessary to monitor the physical parameter such as wave, tide and tidal current especially. Based on the scale and the type of project, we need introduce the system of scoping for prediagnosis the key assessment items and checklists.