이 논문은 미세공정변동에서 극소불량을 감지하는 관리도의 경제적 설계를 개발하기 위한 조사연구이다. 일반적인 관리도의 설계는 통계적 설계와 경제적 설계로 구분할 수 있다. 공정의 변동 원인에 따라 샘플의 간격(h), 샘플의 크기(n), 관리한계선(k) 등의 설계 모수를 최적접근방법으로 결정을 하는 경제적 설계의 모델을 조사하였다. 관리도의 경제적 설계는 공정의 관리이상상태를 효율적으로 감지하여 관리상태로 정상화 시키는 것에 대한 공정의 개선비용과 기대품질비용을 절약 할 수 있는 최적설계 방안이다. 그리고 Shewhart 관리도의 X-bar 통계량으로 극소불량을 검출 하는것에 한계가 있기 때문에 Zp 통계량과 분포를 설계하여 극소불량을 빠르게 감지할 수 있는 Zp 관리도의 설계를 적용하고, 미세공정변동을 정확하게 감지할 수 있는 CUSUM 관리도를 동시에 적용하였다. 따라서, 미세공정변동과 극소불량을 동시에 관리 할 수 있는 Zp-CUSUM 관리도의 통계적 설계 구조를 체계화 하였으며, 기존의 경제적 설계의 모델을 비교 분석하여 새로운 경제적 설계에 대한 모델을 제안하고자 한다.

보증 데이터를 통해 제품의 수명 및 형상모수를 추정할 때 최우추정법과 같은 전통적인 통계 분석방법(Classical Statistical Method)을 많이 사용하였다. 그러나 전통적인 통계 분석방법을 통해 수명과 형상모수의 추정 시 표본의 크기가 작거나 불완전한 경우 추정량의 신뢰성이 떨어진다는 단점이 있고 또 누적된 경험과 과거자료를 충분히 이용하지 못하는 단점도 있다. 이러한 문제점을 해결하기 위해 모수의 사전분포를 가정하는 베이지안(Bayesian) 기법의 적용이 필요하다. 하지만 보증 데이터분석에 있어서 베이지안 기법을 이용한 연구는 아직 미흡한 실정이다. 본 연구에서는 수명분포가 와이블 분포를 갖는 보증데이터를 활용하여 모수 추정의 효율성을 비교 분석하고자 한다. 이를 위해 와이블 분포의 모수가 대수정규분포를 따르는 사전분포를 갖는 베이지안 기법과 전통적 통계기법인 생명표법(Actuarial method)을 활용하여 추정량을 도출하고 비교 분석하였다. 이를 통해 충분한 관측 데이터를 확보할 수 없는 경우에 베이지안 기법을 이용한 보증 데이터 분석방법의 성능을 확인하고자 한다.

우리나라는 비약적인 산업기술발전을 통해 선진국 진입을 눈앞에 두고 있다. 하지만 선진국 진입에 있어 크게 세 가지의 걸림돌이 있다. 첫째로는 세계시장 진입의 장벽, 둘째로 제조물책임법(PL법) 대응방안 미흡, 셋째로는 고객신뢰 및 자원의 한계 이다. 이러한 한계점으로 인하여 신뢰성경영시스템의 필요성이 대두되고 있으며 국내의 신뢰성경영시스템의 활성화는 필수 요소로 다가오고 있다. 본 논문에서는 신뢰성경영시스템의 활성화와 이를 위한 지표개발의 필요성 및 개발 방향성을 제시해보고자 한다.

For the matter of elevator, one of the multi-use facilities for unspecified public, the JIS has re-established and reformed to apply to the environment in South Korea for the past 20 years. In the aspect of safety assurance, it was inevitable to suggest improved measures. The government, Ministry of Public Administration and Security has secured the safety by enhancing the safety management functions in the elevator inspection standards and expanding its safety device measures. Further, the international inspection standard has been introduced, which is about unifying inspection standard system into the international standard code. In March 14th 2012, the international standard (EN) has been amended and fully announced. Escalator and passenger conveyor among lift devices have several common danger factor that cause safety accident. First, the accident caused by decreased braking power of brake. Second, the accident caused by the rate difference between handrail and tread-board. Third, the accident caused by defects of contraflow preventing device or carelessness inspection. Fourth, the accident caused by wet tread-board or wet floor of platform which makes passenger slip and fall. As the improvements to prevent and reduce these negligent accidents, the inspection list to check and methods should be subdivided and applied for each accident likelihood cause for safety management enhancement and safety assurance of existing escalator and passenger conveyors. The escalators and passenger conveyors without safety devices in existence should be obliged to modify the part of the system or install additional safety device. With making these measures obligations, it requires to improve the system to be suitable for the international inspection standard and to have measures to prevent safety accidents. It also needs to arrange improvements for skid accident of tread-board by the external environment factors such as snow and rain.

제조공정에서 사용되어 지는 SPC(Statistical Process Control)관리 기법은 가피원인 을 탐지하여 변동을 감소시키는 통계적 공정관리 시스템이다. SPC의 대표적인 관리 기법으로는 Shewhart관리도, Cusum관리도, EWMA관리도가 있으며 이러한 관리 기법 들은 공정을 보다 안정적으로 관리 할 수 있도록 유지 및 예측하는데 사용 되어 진다. 본 논문에서는 일반적으로 사용되어 지는 Shewhart관리도와 공정 예측에 유리한 EWMA 관리도에 대해 연구해보고 공정변화에 민감하게 반응하는 EWMA 관리도의 적용 사례를 제시하고자 한다.

지진취약도 곡선은 구조물의 피해를 지반가속도에 따른 확률로 나타낸 것으로, 이를 이용하여 구조물의 지진에 대한 손 상확률을 추정할 수 있다. 본 연구에서는 6층, 12층 중복도형 격간벽 구조 시스템에 대한 취약도 곡선을 산출하기 위해 22 쌍의 지반가속도를 이용하여 증분동적해석(Incremental dynamic analysis)을 수행하고, 다양한 지진강도에 대한 파괴확률 을 구하였다. 정형의 격간벽 구조의 해석결과와 1층의 격간벽을 기둥으로 대체한 구조물, 중앙 복도에 기둥이 추가된 구조 물의 해석결과를 비교하였다. 취약도 해석결과에 따르면 동일한 수준의 지진하중에 대하여 중앙 복도에 기둥을 추가한 모 델이 가장 높은 내진 안전성을 갖는 것으로 나타났다.

Male factor infertility or sub-fertility contributed half of all cases of infertility while the semen abnormality is the current topic of argument. Conventional analysis of semen showed poor correlation with fertility. Therefore, evaluation of current semen analysis method is necessary to improve standards of semen assessment. The goal of this study was to investigate that correlation between motion kinematic before and after capacitation and litter size in porcine. Sperm motility and kinematics were measure by computer-assisted sperm analysis (CASA). The motility of spermatozoa was positively correlated with curvilinear velocity (VCL), average path velocity (VAP), and mean amplitude of head lateral displacement (ALH) (p<0.05). Where as VCL positively correlated with VSL, VAP and ALH (p<0.01). Straight-line velocity (VSL) was positively correlated with VAP and ALH (p<0.01). VAP was significantly positively correlated with ALH (p<0.01). Also, we found significant positive correlation among variation of VSL, VAP and ALH (p<0.05). No motility and kinematic parameter are correlated with litter size. However, litter size was significantly correlated with breed (p<0.05). Our results suggested that analysis of sperm motility and kinematics using CASA is questionable for prediction of litter size. However, it has some practical importance to evaluate semen commercially.

In the manufacturing process the most widely used x chart has been applied to control the process mean. Also, Accelerated Life Test(ALT) is commonly used for efficient assurance of product life in development phases, which can be applied in production reliability acceptance test. When life data has lognormal distribution, through censored ALT design so that censored ALT data has asymptotic normal distribution, ALTx control chart integrating x chart and ALT procedure could be applied to control the mean of process in the manufacturing process. In the situation that process variation is controlled, Zp control chart is an effective method for the very small fraction nonconforming of quality characteristic. A simultaneous control scheme with ALTx control chart and Zp control chart is designed for the very small fraction nonconforming of product lifetime.

As of Dec. 31, 2011, the number of nation's escalators accounts for 24,248 units, 5.4% of total elevators in our country, safety accidents take up as many 539 case, 55.2% of total elevators' safety accidents. Escalator safety accidents show high incident ratio of primary safety accidents breaking out by users' careless and abnormal use type, taking up multi-caused accident, which mainly take place from vulnerable age groups such as children under 13, and elders above 65. The Government will have to devote itself for policy and support for the establishment of safety management system fit for current state, the revitalization of preventive education for safety accident, the enhancement of safety awareness to escalators' users in order to secure escalator safety environment on an international level and support domestic industrial development.

This survey focused on consumer's consumption patterns for buying factors of domestic live stock products after foot and mouth disease (FMD). The purpose of this survey was to suggest basic information to reduce consumption when livestock diseases are occurred. Two methods were used for this survey. First method was to investigate internal data to understand consumption patterns when buying domestic livestock products. Second method included empirical analysis to understand how FMD affected consumer's consumption pattern. Survey was conducted in Chuncheon city. As the result of this survey, factors that affected the buying patterns of domestic livestock products were brand and expiration date. These results suggested that consumers recognized brand livestock products were safer than general livestock products and they have more interest for food safety than quality attributes of food when buying domestic livestock products.

국내의 많은 기업들은 품질경영시스템인 ISO 9000 시리즈와 식스시그마 등 기업의 품질 및 제품에 대한 품질을 높이기 위해 품질관리, 품질경영에 많은 시간과 비용을 들여왔다. 하지만 품질인증제도와는 달리 제품의 신뢰성에 관한 경영시스템인증을 받 으려고 하는 기업은 거의 없는 실정이다. 부품·소재나 제품의 신뢰성을 확보하기 위한 방안으로써 신뢰성경영시스템에 대한 인증은 필수적이라 할 수 있다. 신뢰성 관련 기 법들을 표준화하고, 효율적인 경영시스템을 도입하여 운영하고, 여기에 세계적으로 통 용되는 기술체계를 도입하여 기업의 신뢰성경영시스템을 발전시킨다면 우리산업이 당 면한 수출 경쟁력 확보 등의 현안문제 해결에도 도움이 될 수 있다. 본 연구에서는 신 뢰성 경영시스템 인증제도 수립에 있어 국제 표준인 신뢰성경영시스템 IEC 60300에 대해 소개하고, 신뢰성 경영시스템 평가방법을 활용한 MIR기법과 AHP기법을 분석 비 교하고, 개선방향을 제시하고자 한다.

The issue is all about the study of warranty data collection and the analysis method to get a reasonable information of the products and improve reliability. In this paper, we consider the classification of warranty data analyses into a parametric and non-parametric analysis and method to get a reasonable information of the products. Also, it is considered the research trend by grouping the relationship among the studies. This study would be used to find the effective application and the condition of warranty data analysis.

Salmonellosis constitutes an important public health problem in both developing and developed countries, including Korea. The aims of present study were to investigate the serovar and antimicrobial resistance of Salmonella isolated from food animals and animal products in slaughterhouses and farms. A total of 323 Salmonella were isolated from food animals (n=277) and meats (n=46) during 2010. Of the isolates, 21 different serovars were identified. The predominant serovars were S. Rissen (35%) and S. Montevideo (24.3) in healthy pigs, while S. Enteritidis (25.5%) in healthy chicken. S. Typhimurium (88.8%) was predominant in disease pigs, while S. Gallinarum (29.2%) and S. Montevideo (26.9%) were in diseased chickens. Among meat samples, S. Typhimurium (57.1%) was the most common serovar in pork but S. Enteritidis (38.7%) and S. Montevideo(32.3%) were in chikcen meats. Analysis of antimicrobial resistance patterns revealed that 20.7% of the isolates were sensitive to all the 15 drugs tested. The isolates were frequently resistant to nalidixic acid (47.7%), tetracycline (38.4%), streptomycin (33.7%), and ampicillin (32.8%). The resistance to quinolone and 3rd generation cephalosporins was higher in chicken and chicken meat isolates. Of the 323 isolates, 174 (53.9%) were resistant to one or more CLSI subclass, and 117 (36.2%) showed multiple-resistance. Our findings showed that multiple resistant Salmonella organism are widespread in animals and animal products in Korea. To prevent the transmission or exposure for consumers of antimicrobial resistant Salmonella, policies and guidelines aiming at prudential use of critical antimicrobials for humans are needed.

Campylobacterosis is the most common food borne bacterial disease in many countries. Food animals and animal products are considered to be the reservoir of the Campylobacter species. The aim of this study was to investigate the antimicrobial resistance of Campylobacter spp. from food animals and raw meats in slaughterhouses. A total of 90 Campylobacter jejuni (C. jejuni) and 127 Campylobacter coli (C. coli) were isolated, for which antimicrobial susceptibility was examined using broth dilution method. Resistance to macrolide antimicrobials was higher among C. coli isolates than among C. jejuni. Among both C. jejuni and C. coli isolates, the most frequently observed resistance was to nalidixic acid, ciprofloxacin, and tetracycline. No erythromycin resistance was observed among C. jejuni isolates from cattle, pig and beef. However, 28.3% (n=13) and 25% (n=3) of C. coli isolates from pigs and pork showed resistance to erythromycin, respectively. The predominant profile of multiple resistance among C. jejuni and C. coli isolates was ciprofloxacin/tetracycline/nalidixic acid resistance (46.7%) and ciprofloxacin/nalidixic acid resistance (31.5%), respectively. This finding has important implication for food safety and public health.

Staphylococcus aureus is an important food-borne pathogen, which is present on the skin and mucosa of animals. Some of the S. aureus strains are causative agent of food poisoning syndrome. The aim of this study was to investigate the antimicrobial resistance of S. aureus isolates from raw meats in slaughterhouses during 2010. From 17,874 raw meat samples tested, a total of 190 S. aureus were isolated, for which antimicrobial susceptibility to 17 agents was examined using broth dilution method. Among isolates from beef, chicken and pork, 20 (51.3%), 20 (24.7%) and 9 (12.9%) were sensitive to all antimicrobials tested, respectively. Isolates from pork and chicken meats showed much higher resistance, compared to isolates from beef. Penicillin resistance was the most frequent among isolates from beef (35.3%) and pork (75.7%), while tetracycline resistance was among those from chicken meats (48.1%). A total of 3 methicillin resistant S. aureus (MRSA) were detected from beef (5.1%, 2/39) and pork (1.4%, 1/70). Although the prevalence of MRSA was low, the presence of antimicrobial resistant S. aureus such as MRSA suggests that further investigation and strict surveillance on MRSA and antimicrobial resistance are needed.

Customers are generally requiring a variety of products, earlier due date, and lower price. A manufacturing process needs the efficient scheduling to meet those customer's requirements. This study proposes the novel algorithm named MJA(Minimum Job completion time and AGV time) that increases the performance of machines and AGV(Automated Guided Vehicles) in many kinds of job types. MJA optimizes the bottleneck of machines and efficiency of AGV with considering two types of dispatching at the same time. Suggested algorithm was compared with existing heuristic methods by several simulations, it performed better for reducing the time of tardiness.

Control chart is most widely used in SPC(Statistical Process Control), Recently it is a critical issue that the standard control chart is not suitable to non-normal process with very small percent defective. Especially, this problem causes serious errors in the reliability procurement, such as semiconductor, high-precision machining and chemical process etc. Procuring process control technique for non-normal process with very small percent defective and perturbation is becoming urgent. Control chart technique in non-normal distribution become very important issue. In this paper, we investigate on research trend of control charts under non-normal distribution with very small percent defective and perturbation, and propose some variable-transformation methods applicable to CUSUM control charts in non-normal process.