• 제목/요약/키워드: defective products

검색결과 161건 처리시간 0.03초

봉제기술자(縫製技術者)를 통해서 본 대구시(大邱市) 숙녀복업계(淑女服業界)의 현항(現況) (A Study on The Manufacturing Industries of Women's Wear in Taegu Through the Sewing Technicians)

  • 김효은;김순분
    • 패션비즈니스
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    • 제2권4호
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    • pp.102-111
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    • 1998
  • The purpose of this study is to present the basic material for the competitive, high-quality products by analyzing employees' attitude toward their job and some factors which influence the enhancement of productivity, education of workers, and facilities. This project was mainly conducted the conditions of women's wear manufacturing industries in Taegu by interviewing 143 employees in the sewing department. The result of this dissertation can be summarized as follows; 1. When it comes to the division of task in the sewing department, one team is composed of chairpersons (33.5%), assistant members (27.4%) and sub-assistant members (26.6%). The inspection of commodities as well as the enhancement of work on ironing for elaboration was divided as completion (12.6%) and finally the forms of task were made up of design sampling team (49%) and contracting team (51%). 2. Among the needle workers, as many as 60% employees had received technical education, which was by means of being passed down from the predecessors (81.6%). In terms of the period of education, from 2 to 5 years topped the list. The contents of education comprise patterning, sewing (65.2%) and ironing (20.3%). 3. The department of design takes charge of the report on working directions up to 88.2% and the working directions were used by 69.9 % of technicians. The directors of working conditions and methods were chiefs of designing department (37.7%) and those of sewing department (30.8%). The factors of defective goods were low-quality materials (50.0%), the deficiency in skills of workers. In terms of methods for preventing defects, technical education of workers, standardization of task and investment for factory automation were suggested. 4. As for their perception of present work, most of employees (80%) look upon it as a way of earning a living and 11% of them wanted to derive many things from their work. 59.2% of workers were satisfied with the product. When it comes to the incentive system provided by company, 67.0% responsed that it was not bad, and 23.9% evaluated it as 'satisfactory'.

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참돔과 홍민어 판별을 위한 Multiplex PCR 검사법의 개발과 검증 (Development and Validation of Multiplex PCR Method for the Identification of Pagrus major and Sciaenops ocellatus)

  • 최이슬;신지영;양지영
    • 한국식품위생안전성학회지
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    • 제35권6호
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    • pp.561-566
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    • 2020
  • 참돔은 등쪽에 푸른 반점이 흩어져 있고, 홍민어는 꼬리 쪽에 검은 점이 있어 원물 형태는 쉽게 구분할 수 있다. 그러나 횟감이나 필렛으로 이용 시 참돔과 홍민어를 구분하기 어려워, 참돔의 종 특이 primer를 개발 및 검증하고 모니터링을 통해 참돔의 위변조 사례를 조사하고자 하였다. 시료에서 gDNA를 추출하여 PCR을 진행하였으며 참돔 primer의 product size는 468 bp, 홍민어 primer의 product size는 181 bp으로 설계하였다. Multiplex PCR 결과 참돔과 홍민어에 대한 종 특이적 증폭이 확인되었다. 또한, 참돔과 홍민어 PCR 민감도 실험 결과 참돔 primer는 1 ng, 홍민어 primer는 0.1 ng 까지 밴드가 확인되었다. 모니터링 결과 참돔으로 구매한 시료 19건 모두 참돔으로 판정되었다. 따라서 본 연구에서 제작된 참돔과 홍민어 종에 대한 종 특이적 primer는 횟감 등 수산물에도 적용할 수 있어 현재 유통 및 판매되고 있는 참돔 및 홍민어 판별에 적합성을 확인하였다.

쾌삭 303계 스테인리스강 소형 압연 선재 제조 공정의 생산품질 예측 모형 (Quality Prediction Model for Manufacturing Process of Free-Machining 303-series Stainless Steel Small Rolling Wire Rods)

  • 서석준;김흥섭
    • 산업경영시스템학회지
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    • 제44권4호
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    • pp.12-22
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    • 2021
  • This article suggests the machine learning model, i.e., classifier, for predicting the production quality of free-machining 303-series stainless steel(STS303) small rolling wire rods according to the operating condition of the manufacturing process. For the development of the classifier, manufacturing data for 37 operating variables were collected from the manufacturing execution system(MES) of Company S, and the 12 types of derived variables were generated based on literature review and interviews with field experts. This research was performed with data preprocessing, exploratory data analysis, feature selection, machine learning modeling, and the evaluation of alternative models. In the preprocessing stage, missing values and outliers are removed, and oversampling using SMOTE(Synthetic oversampling technique) to resolve data imbalance. Features are selected by variable importance of LASSO(Least absolute shrinkage and selection operator) regression, extreme gradient boosting(XGBoost), and random forest models. Finally, logistic regression, support vector machine(SVM), random forest, and XGBoost are developed as a classifier to predict the adequate or defective products with new operating conditions. The optimal hyper-parameters for each model are investigated by the grid search and random search methods based on k-fold cross-validation. As a result of the experiment, XGBoost showed relatively high predictive performance compared to other models with an accuracy of 0.9929, specificity of 0.9372, F1-score of 0.9963, and logarithmic loss of 0.0209. The classifier developed in this study is expected to improve productivity by enabling effective management of the manufacturing process for the STS303 small rolling wire rods.

Precise control of mitophagy through ubiquitin proteasome system and deubiquitin proteases and their dysfunction in Parkinson's disease

  • Park, Ga Hyun;Park, Joon Hyung;Chung, Kwang Chul
    • BMB Reports
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    • 제54권12호
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    • pp.592-600
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    • 2021
  • Parkinson's disease (PD) is one of the most common neurodegenerative diseases in the elderly population and is caused by the loss of dopaminergic neurons. PD has been predominantly attributed to mitochondrial dysfunction. The structural alteration of α-synuclein triggers toxic oligomer formation in the neurons, which greatly contributes to PD. In this article, we discuss the role of several familial PD-related proteins, such as α-synuclein, DJ-1, LRRK2, PINK1, and parkin in mitophagy, which entails a selective degradation of mitochondria via autophagy. Defective changes in mitochondrial dynamics and their biochemical and functional interaction induce the formation of toxic α-synuclein-containing protein aggregates in PD. In addition, these gene products play an essential role in ubiquitin proteasome system (UPS)-mediated proteolysis as well as mitophagy. Interestingly, a few deubiquitinating enzymes (DUBs) additionally modulate these two pathways negatively or positively. Based on these findings, we summarize the close relationship between several DUBs and the precise modulation of mitophagy. For example, the USP8, USP10, and USP15, among many DUBs are reported to specifically regulate the K48- or K63-linked de-ubiquitination reactions of several target proteins associated with the mitophagic process, in turn upregulating the mitophagy and protecting neuronal cells from α-synuclein-derived toxicity. In contrast, USP30 inhibits mitophagy by opposing parkin-mediated ubiquitination of target proteins. Furthermore, the association between these changes and PD pathogenesis will be discussed. Taken together, although the functional roles of several PD-related genes have yet to be fully understood, they are substantially associated with mitochondrial quality control as well as UPS. Therefore, a better understanding of their relationship provides valuable therapeutic clues for appropriate management strategies.

플래너 밀러 재제조를 위한 역설계 및 마모 분석에 관한 연구 (A Study on the Reverse Engineering and Wear Analysis for Remanufacturing Planner Miller)

  • 최두한;공석환;변정원;김태우;홍대선
    • 한국산업융합학회 논문집
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    • 제25권6_2호
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    • pp.1103-1110
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    • 2022
  • The old machine tools that have been used for a long time cause both increase in defective rate and decrease in productivity compared to new machines due to wear and failure of their components. In order to improve productivity and quality of machined components through remanufacturing, it is necessary to analyze the wear and failure of major components of old machine tools. In this study, the process for reverse engineering is designed for the remanufacture of planner millers, which belong to a very large machine tool. Also, the suitability of the designed process is verified through the analysis of the selected remanufactured components. In the first step of the process, some major components of the aging planner miller are scanned using a 3D laser scanner. In the next step, reverse engineering is performed using the data obtained through 3D scanning. Finally, wear and failure analysis is performed by comparing the reverse engineering data with the scan data. As a result, this reverse design and wear analysis can complement the insufficient design database and reduce costs in the maintenance of remanufactured products.

이미지 기반 축산물 불량 탐지에서의 희소 클래스 처리 전략 (Sparse Class Processing Strategy in Image-based Livestock Defect Detection)

  • 이범호;조예성;이문용
    • 한국정보통신학회논문지
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    • 제26권11호
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    • pp.1720-1728
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    • 2022
  • 인공지능 기술의 발전으로 산업 4.0시대가 열렸고 축산업에서도 ICT 기술이 접목된 스마트 농장의 구현이 큰 관심을 받고 있다. 그중에서도 컴퓨터 비전 기반 인공지능 기술을 접목한 축산물 및 축산 가공품의 품질 관리 기술은 스마트 축산의 핵심 기술에 해당한다. 그러나 인공지능 모형 훈련을 위한 축산물 이미지 데이터 수의 부족과 특정 범주(class)에 대한 데이터 불균형은 관련 연구 및 기술 개발에 큰 장해물이 되고 있다. 이러한 문제들을 해결하기 위해, 본 연구에서는 오버샘플링과 적대적 사례 생성기법의 활용을 제안한다. 제안되는 방법은 성공적인 불량 탐지 (Defect detection) 관점을 기반으로 하며, 이는 부족한 데이터 레이블을 효과적으로 활용하는데 필요한 방법이다. 최종적으로 실험을 통해 제안된 방법의 타당성을 확인하고 활용 전략을 검토한다.

YOLOv3을 이용한 과일표피 불량검출 모델: 복숭아 사례 (Detection Model of Fruit Epidermal Defects Using YOLOv3: A Case of Peach)

  • 이희준;이원석;최인혁;이충권
    • 경영정보학연구
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    • 제22권1호
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    • pp.113-124
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    • 2020
  • 농가를 운영함에 있어서 수확한 작물에 대한 품질을 평가하여 불량품을 분류하는 작업은 매우 중요하다. 그러나, 농가는 부족한 자본과 인력으로 인하여 품질평가에 소요되는 비용과 시간을 감당하는데 어려움이 있다. 이에 본 연구는 인공지능 기술인 딥 러닝 알고리즘을 이용하여 과일의 표피를 분석함으로써 불량을 검출하고자 한다. 과일을 촬영한 동영상 이미지에 대하여 영역기반 합성곱 신경망(Region Convolutional Neural Network)을 기반으로 한 YOLOv3 알고리즘을 적용하여 표피를 분석할 수 있는 모델을 개발하였다. 총 4개의 클래스를 정해서 학습을 진행하였고, 총 97,600번의 epoch을 통해서 우수한 성능의 불량검출 모델을 얻을 수 있었다. 본 연구에서 제안한 농작물 불량검출 모델은 데이터 수집, 분석된 데이터를 통한 품질평가, 그리고 불량검출에 이르는 과정의 자동화에 활용될 수 있다. 특히, 농작물들 중에서도 외상에 가장 취약한 복숭아를 대상으로 분석모델을 개발하였기 때문에, 다른 작물에도 적용될 수 있을 것으로 기대된다.

지각 추출물이 quinone reductase 및 glutathion s-transferase의 유도활성에 미치는 영향 (Induction of Quinone Reductase and Glutathion S-transferase in Hepatoma Cells by Citrus aurantium Linn (Jikak) Produced in Cheju Island)

  • 유미희;이인선
    • 한국식품과학회지
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    • 제37권2호
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    • pp.261-267
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    • 2005
  • Phase II 효소계는 자연계에 존재하는 다양한 화학물질과 천연소재들에 의해 유도되며, 이들의 유도는 화학적 발암물질과 그 밖의 여러 가지 독성물질들로부터 생체를 보호하는데 중요한 역할을 한다. 특히, phase II 효소 중 QR은 quinone류 자체에 대한 보호효과가 있고 다른 암예방 효소계와 공통으로 유도되며, 항암 작용이 있는 많은 화합물에 의해 유도되어지기 때문에 암예방 물질 탐색의 지표가 되는 대표적인 효소로 많이 이용된다. 본 연구에서는 제주도에서 자생하는 귤류 중 지각을 이용하여 메탄올추출물을 제조한 후 대표적인 암예방계 효소로 알려진 quinone reductase 및 glutathion S-transferase의 유도 활성을 조사하였다. 우선 QR 및 GST 유도활성 측정에 앞서 각 시료의 Hepa 1c1c7 세포에 대한 독성을 조사하여 시료자체의 세포독성을 관찰하였으며, 이 결과를 바탕으로 QR, GST 유도 활성을 측정할 시 세포독성을 거의 나타내지 않는 각각 시료의 최대 처리 농도를 결정하였다. 총 6개의 지각 분획물 중 mouse 유래 Hepa 1c1c7 세포주에서는 hexane 충과 chloroform 충에서 QR, GST의 활성이 $200{\mu}g/mL$에서 각각 1.8배, 1.5배 이상으로 증가되어 높은 QR 및 GST의 유도활성을 보였다. 따라서 지각의 hexane 층이나 chloroform층에 존재하는 높은 QR및 GST의 유도활성이 나타나는 물질을 분리 정제하여 앞으로 계속적인 연구가 진행되어야 할 것이다.

제품태도에 대한 회복노력의 차별적 효과 (Differential Effects of Recovery Efforts on Products Attitudes)

  • 김천길;최정미
    • 마케팅과학연구
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    • 제18권1호
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    • pp.33-58
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    • 2008
  • 본 연구는 서비스실패가 아니라 제품실패 이후, 회복노력의 효과를 실패심각성에 따라 확인하는 것이다. 회복노력은 보상노력, 장점노력 및 단점노력으로 구분되었다. 보상노력은 실패상황을 직접적으로 되돌리려는 의도로 구체적인 보상을 제공하는 방안으로, 장점노력은 제품실패를 초래하는 이유가 특정한 장점을 추구하는 과정에서 불가피하게 발생할 수 있는 문제임을 언급하는 것과 같이 추가적인 상대적 장점을 설명하는 방식으로, 그리고 단점노력은 자사제품이 서비스실패를 초래할 수 있는 문제점을 지니고 있는 반면에 경쟁제품은 또 다른 측면의 단점을 지니고 있다는 점을 부각시켜 소비자의 자사제품에 대한 부정적 태도를 회복시키려고 방안이라고 개념화되었다. 그러한 회복노력들이 실질적으로 효과가 있다고 결론을 내리기 위해서, 회복노력이 제공되지 않는 상황과 비교하여 소비자의 태도나 의향이 우호적인지 검토된다. 가설검증을 위해 화장품산업에서 소비자들을 대상으로 가상적인 시나리오를 이용한 실험을 실시하였다. 연구 결과, 전반적으로 회복노력들은 효과적인 전략임이 확인되었고, 보상노력은 장점노력이나 단점 노력보다 효과적이었다. 특히 심각성이 높은 실패조건에서 단점노력은 장점노력보다 긍정적인 제품태도를 유도하였다. 심각성이 낮은 실패조건에서 장점노력과 장점노력의 효과는 기대할 수 없었다.

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상업우주사업(商業宇宙事業) 참가기업(參加企業)의 책임(責任)과 우주보험(宇宙保險) (The Liability of Participants in Commercial Space Ventures and Space Insurance)

  • 이강빈
    • 항공우주정책ㆍ법학회지
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    • 제5권
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    • pp.101-118
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    • 1993
  • Generally there is no law and liability system which applies particulary to commercial space ventures. There are several international treaties and national statutes which deal with space ventures, but their impact on the liability of commercial space ventures has not been significant. Every state law in the United States will impose both tort and contract liability on those responsible for injuries or losses caused by defective products or by services performed negligently. As with the providers of other products and services, those who participate in commercial space ventures have exposure to liability in both tort and contract which is limited to the extent of the resulting damage The manufacturer of a small and cheap component which caused a satellite to fail to reach orbit or to operate nominally has the same exposure to liability as the provider of launch vehicle or the manufacturer of satellite into which the component was incorporaded. Considering the enormity of losses which may result from launch failure or satellite failure, those participated in commercial space ventures will do their best to limit their exposure to liability by contract to the extent permitted by law. In most states of the United States, contracts which limit or disclaim the liability are enforceable with respect to claims for losses or damage to property if they are drafted in compliance with the requirements of the applicable law. In California an attempt to disclaim the liability for one's own negligence will be enforceable only if the contract states explicitly that the parties intend to have the disclaimer apply to negligence claims. Most state laws of the United States will refuse to enforce contracts which attempt to disclaim the liability for gross negligence on public policy grounds. However, the public policy which favoured disclaiming the liability as to gross negligence for providers of launch services was pronounced by the United States Congress in the 1988 Amendments to the 1984 Commercial Space Launch Act. To extend the disclaimer of liability to remote purchasers, the contract of resale should state expressly that the disclaimer applies for the benefit of all contractors and subcontractors who participated in producing the product. This situation may occur when the purchaser of a satellite which has failed to reach orbit has not contracted directly with the provider of launch services. Contracts for launch services usually contain cross-waiver of liability clauses by which each participant in the launch agrees to be responsible for it's own loss and to waive any claims which it may have against other participants. The crosswaiver of liability clause may apply to the participants in the launch who are parties to the launch services agreement, but not apply to their subcontractors. The role of insurance in responding to many risks has been critical in assisting commercial space ventures grow. Today traditional property and liability insurance, such as pre-launch, launch and in-orbit insurance and third party liability insurance, have become mandatory parts of most space projects. The manufacture and pre-launch insurance covers direct physical loss or damage to the satellite, its apogee kick moter and including its related launch equipment from commencement of loading operations at the manufacture's plant until lift off. The launch and early orbit insurance covers the satellite for physical loss or damage from attachment of risk through to commissioning and for some period of initial operation between 180 days and 12 months after launch. The in-orbit insurance covers physical loss of or damage to the satellite occuring during or caused by an event during the policy period. The third party liability insurance covers the satellite owner' s liability exposure at the launch site and liability arising out of the launch and operation in orbit. In conclusion, the liability in commercial space ventures extends to any organization which participates in providing products and services used in the venture. Accordingly, it is essential for any organization participating in commercial space ventures to contractually disclaim its liability to the extent permitted by law. To achieve the effective disclaimers, it is necessary to determine the applicable law and to understand the requirements of the law which will govern the terms of the contract. A great deal of funds have been used in R&D for commercial space ventures to increase reliability, safety and success. However, the historical reliability of launches and success for commercial space ventures have proved to be slightly lower than we would have wished for. Space insurance has played an important role in reducing the high risks present in commercial space ventures.

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