• Title/Summary/Keyword: defective products

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

  • Kim,, Hyo-Eun;Kim, Soon-Boon
    • Journal of Fashion Business
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    • v.2 no.4
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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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Development and Validation of Multiplex PCR Method for the Identification of Pagrus major and Sciaenops ocellatus (참돔과 홍민어 판별을 위한 Multiplex PCR 검사법의 개발과 검증)

  • Choi, Iseul;Shin, Jiyoung;Yang, Ji-young
    • Journal of Food Hygiene and Safety
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    • v.35 no.6
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    • pp.561-566
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    • 2020
  • Nowadays, with increase of seafood consumption, there have been increasing reports of defective seafood products. There have been incidents of red drum (Sciaenops ocellatus) being sold as red seabream (Pagrus major). In this study, we sought to develop and validate species-specific PCRs to differentiate between P. major and S. ocellatus to prevent the sale of S. ocellatus as P. major. Primers for P. major were designed to bind 12s rRNA and those for S. ocellatus were designed to bind 16s rRNA. Multiplex PCR showed a 468 bp amplicon for P. major and a 181 bp amplicon for S. ocellatus. The limit of detection of P. major and S. ocellatus was present at 1 ng each. The developed primers were validated with 19 P. major samples of food items purchased through the internet. Using this monitoring method, the experimental results and tested species were in agreement. Hence, the developed multiplex PCR method is considered reliable to authenticate P. major and S. ocellatus.

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

  • Seo, Seokjun;Kim, Heungseob
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.44 no.4
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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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    • v.54 no.12
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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.

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

  • Choi, Doo-Han;Kong, Seok-Hwan;Byeon, Jeong-Won;Kim, Tae-Woo;Hong, Dae-Sun
    • Journal of the Korean Society of Industry Convergence
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    • v.25 no.6_2
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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.

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

  • Lee, Bumho;Cho, Yesung;Yi, Mun Yong
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.26 no.11
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    • pp.1720-1728
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    • 2022
  • The industrial 4.0 era has been opened with the development of artificial intelligence technology, and the realization of smart farms incorporating ICT technology is receiving great attention in the livestock industry. Among them, the quality management technology of livestock products and livestock operations incorporating computer vision-based artificial intelligence technology represent key technologies. However, the insufficient number of livestock image data for artificial intelligence model training and the severely unbalanced ratio of labels for recognizing a specific defective state are major obstacles to the related research and technology development. To overcome these problems, in this study, combining oversampling and adversarial case generation techniques is proposed as a method necessary to effectively utilizing small data labels for successful defect detection. In addition, experiments comparing performance and time cost of the applicable techniques were conducted. Through experiments, we confirm the validity of the proposed methods and draw utilization strategies from the study results.

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

  • Hee Jun Lee;Won Seok Lee;In Hyeok Choi;Choong Kwon Lee
    • Information Systems Review
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    • v.22 no.1
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    • pp.113-124
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    • 2020
  • In the operation of farms, it is very important to evaluate the quality of harvested crops and to classify defective products. However, farmers have difficulty coping with the cost and time required for quality assessment due to insufficient capital and manpower. This study thus aims to detect defects by analyzing the epidermis of fruit using deep learning algorithm. We developed a model that can analyze the epidermis by applying YOLOv3 algorithm based on Region Convolutional Neural Network to video images of peach. A total of four classes were selected and trained. Through 97,600 epochs, a high performance detection model was obtained. The crop failure detection model proposed in this study can be used to automate the process of data collection, quality evaluation through analyzed data, and defect detection. In particular, we have developed an analytical model for peach, which is the most vulnerable to external wounds among crops, so it is expected to be applicable to other crops in farming.

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

  • Yu, Mi-Hee;Lee, In-Seon
    • Korean Journal of Food Science and Technology
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    • v.37 no.2
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    • pp.261-267
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    • 2005
  • Phase II enzymes are transcriptionally induced by synthetic chemical agents and natural products, and such induction plays critical roles in protection against chemical carcinogens and other toxic xenobiotics. To discover natural products for use as cancer chemopreventive agents, the ability of Citrus aurantium Linn (Jikak) to induce activities of quinone reductase (QR) and glutathione S-transferase (GST) in wild-type murine hepatoma cell line (Hepa 1c1c7) and Ah-receptor-defective mutant of the same cell line (Bprcl) was investigated. Hexane and chloroform fractions of C. aurantium Linn (Jikak) at doses not exhibiting cytotoxicity were effective inducers of QR (${\sim}1.8-fold$) and GST (${\sim}1.5-fold$) in Hepa 1c1c7 cells, whereas showed low QR induction potency in Bprcl cells, which indicates they have weak monofunctional action. Results suggest C. aurantium Linn (Jikak) as potentially useful cancer chemopteventive agent.

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

  • Kim, Cheon-GIl;Choi, Jung-Mi
    • Journal of Global Scholars of Marketing Science
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    • v.18 no.1
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    • pp.33-58
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    • 2008
  • Previous research has presupposed that the evaluation of consumer who received any recovery after experiencing product failure should be better than the evaluation of consumer who did not receive any recovery. The major purposes of this article are to examine impacts of product defect failures rather than service failures, and to explore effects of recovery on postrecovery product attitudes. First, this article deals with the occurrence of severe and unsevere failure and corresponding service recovery toward tangible products rather than intangible services. Contrary to intangible services, purchase and usage are separable for tangible products. This difference makes it clear that executing an recovery strategy toward tangible products is not plausible right after consumers find out product failures. The consumers may think about backgrounds and causes for the unpleasant events during the time gap between product failure and recovery. The deliberation may dilutes positive effects of recovery efforts. The recovery strategies which are provided to consumers experiencing product failures can be classified into three types. A recovery strategy can be implemented to provide consumers with a new product replacing the old defective product, a complimentary product for free, a discount at the time of the failure incident, or a coupon that can be used on the next visit. This strategy is defined as "a rewarding effort." Meanwhile a product failure may arise in exchange for its benefit. Then the product provider can suggest a detail explanation that the defect is hard to escape since it relates highly to the specific advantage to the product. The strategy may be called as "a strengthening effort." Another possible strategy is to recover negative attitude toward own brand by giving prominence to the disadvantages of a competing brand rather than the advantages of its own brand. The strategy is reflected as "a weakening effort." This paper emphasizes that, in order to confirm its effectiveness, a recovery strategy should be compared to being nothing done in response to the product failure. So the three types of recovery efforts is discussed in comparison to the situation involving no recovery effort. The strengthening strategy is to claim high relatedness of the product failure with another advantage, and expects the two-sidedness to ease consumers' complaints. The weakening strategy is to emphasize non-aversiveness of product failure, even if consumers choose another competitive brand. The two strategies can be effective in restoring to the original state, by providing plausible motives to accept the condition of product failure or by informing consumers of non-responsibility in the failure case. However the two may be less effective strategies than the rewarding strategy, since it tries to take care of the rehabilitation needs of consumers. Especially, the relative effect between the strengthening effort and the weakening effort may differ in terms of the severity of the product failure. A consumer who realizes a highly severe failure is likely to attach importance to the property which caused the failure. This implies that the strengthening effort would be less effective under the condition of high product severity. Meanwhile, the failing property is not diagnostic information in the condition of low failure severity. Consumers would not pay attention to non-diagnostic information, and with which they are not likely to change their attitudes. This implies that the strengthening effort would be more effective under the condition of low product severity. A 2 (product failure severity: high or low) X 4 (recovery strategies: rewarding, strengthening, weakening, or doing nothing) between-subjects design was employed. The particular levels of product failure severity and the types of recovery strategies were determined after a series of expert interviews. The dependent variable was product attitude after the recovery effort was provided. Subjects were 284 consumers who had an experience of cosmetics. Subjects were first given a product failure scenario and were asked to rate the comprehensibility of the failure scenario, the probability of raising complaints against the failure, and the subjective severity of the failure. After a recovery scenario was presented, its comprehensibility and overall evaluation were measured. The subjects assigned to the condition of no recovery effort were exposed to a short news article on the cosmetic industry. Next, subjects answered filler questions: 42 items of the need for cognitive closure and 16 items of need-to-evaluate. In the succeeding page a subject's product attitude was measured on an five-item, six-point scale, and a subject's repurchase intention on an three-item, six-point scale. After demographic variables of age and sex were asked, ten items of the subject's objective knowledge was checked. The results showed that the subjects formed more favorable evaluations after receiving rewarding efforts than after receiving either strengthening or weakening efforts. This is consistent with Hoffman, Kelley, and Rotalsky (1995) in that a tangible service recovery could be more effective that intangible efforts. Strengthening and weakening efforts also were effective compared to no recovery effort. So we found that generally any recovery increased products attitudes. The results hint us that a recovery strategy such as strengthening or weakening efforts, although it does not contain a specific reward, may have an effect on consumers experiencing severe unsatisfaction and strong complaint. Meanwhile, strengthening and weakening efforts were not expected to increase product attitudes under the condition of low severity of product failure. We can conclude that only a physical recovery effort may be recognized favorably as a firm's willingness to recover its fault by consumers experiencing low involvements. Results of the present experiment are explained in terms of the attribution theory. This article has a limitation that it utilized fictitious scenarios. Future research deserves to test a realistic effect of recovery for actual consumers. Recovery involves a direct, firsthand experience of ex-users. Recovery does not apply to non-users. The experience of receiving recovery efforts can be relatively more salient and accessible for the ex-users than for non-users. A recovery effort might be more likely to improve product attitude for the ex-users than for non-users. Also the present experiment did not include consumers who did not have an experience of the products and who did not perceive the occurrence of product failure. For the non-users and the ignorant consumers, the recovery efforts might lead to decreased product attitude and purchase intention. This is because the recovery trials may give an opportunity for them to notice the product failure.

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

  • Lee, Kang-Bin
    • The Korean Journal of Air & Space Law and Policy
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    • v.5
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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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