• 품질경영학회지
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• 제21권1호
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• pp.22-34
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• 1993

In claiming for the purchased products, two types of errors can occur from the consumer's point of view. One is to accept defective products and the other one is to reject good products. Due to such errors, Claim rate for the products is expected to be different from that the producer has originally anticipated. In this paper, the probability distribution of the number of claimed products when such consumer's inspection errors are involved is derived. Then, a simple model is provided to estimate the claim rate when such errors are present.

• 반도체디스플레이기술학회지
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• 제22권2호
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• pp.40-44
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• 2023

The defect detection based on deep learning requires minimal loss and high accuracy to pinpoint product defects. In this paper, we confirm the loss rate of deep learning training based on disc-shaped artificial scaffold images. It is intended to compare the performance of Cross-Entropy functions used in object detection algorithms. The model was constructed using normal, defective artificial scaffold images and category cross entropy and sparse category cross entropy. The data was repeatedly learned five times using each loss function. The average loss rate, average accuracy, final loss rate, and final accuracy according to the loss function were confirmed.

• 한국가축번식학회지
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• 제25권2호
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• pp.171-180
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• 2001

형질전환 가금의 생산에 있어서 retrovirus vector를 이용하는 방법은 다양한 종류의 표적세포에 대하여 retrovirus 고유의 감염성에 의한 외래 유전자의 전이가 용이하고, 전이된 유전자가 진정염색질 영역 내로 선택적으로 도입될 수 있으며 유전적으로 안정성을 나타내므로 매우 효과적인 방법이다. 그러나 가금에서는 초기 배발달에 의한 급격한 세포의 수적 증가로 인해 고감염성의 virus의 획득이 요구되므로, 이를 위하여 virus stock의 농축에 있어 보다 안정적이고 pantropic인 vesicular stomatitis virus (VSV G) glycoprotein를 envelope로 가지는 pseudotyped retrovirus vector system을 이용하였으며, marker gene으로 eGFP gene이 발현되는 retrovirus를 생산하였다. 이 virus를 이용하여 여러 가지 표적세포와 primary culture한 CEF세포를 감염시켜 GFP의 발현을 확인하였으며, 농축한 virus stock은 stage X의 계란을 선택하여 windowed egg를 제작한 후 배하층에 주입하였다. 형질전환 닭은 정상 발생한 닭에 비하여 저조한 발생율을 보였으나 PCR을 이용하여 외래 유전자의 도입을 확인한 결과 100%인 것으로 나타났다. 또한 한 개체 내에서 유전자의 도입이 폐, 간, 정소, 소장 등의 여러 장기에서 확인되었다.

• 산업경영시스템학회지
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• 제45권1호
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• pp.31-40
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• 2022

Six Sigma is a philosophy and systematic methodology for quality improvement. It encourages continuous quality improvement efforts to achieve the ideal goal of 6σ. Sigma(σ) is a statistic representing the standard deviation of the normal distribution, and 6σ level means a level where the tolerance of the specification is six times the standard deviation of the process distribution. In terms of the defective rate, the 6σ level achieves the 0.002 defectives per one million units. However, in the field, the 6σ level is used in the sense of achieving 3.4 defects per one million opportunities, which shows a large gap from the 6σ level in the statistical viewpoint. This is because field practitioners accept a 1.5σ shift of the mean of process when calculating the defective rate under sigma level. It said that the acceptance of 1.5σ shift of the mean is from experience, but there is no research or theoretical explanation to support it logically. Although it is a non-scientific explanation based on experience, considering that there has been no objection to the 1.5σ shift for a long time and it is rather accepted, it is judged that there is a reasonable basis for the 1.5σ shift. Therefore, this study tries to find a reasonable explanation through detective power of control chart via the run-rules to the 1.5σ shift empirically recognized by practitioners.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2010년도 하계학술대회 논문집
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• pp.262-262
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• 2010

To investigate the effect of the amount of hydrogen on CVD grown-graphene, the flow rate of hydrogen was changed, while other process parameters were kept constant during CVD synthesis. Substrate which consists of 300nm-nickel/$SiO_2$/Si substrate, and methane gas mixed with hydrogen and argon were used for CVD growth. Graphene was synthesized at $950^{\circ}C$. The thickness and the defect of graphene were analyzed using raman spectroscopy. The synthesized graphene shows non-uniform and more defective below a certain amount of hydrogen.

• KIEE International Transactions on Electrophysics and Applications
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• 제5C권3호
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• pp.138-142
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• 2005

In this paper, we compared recognition rates between NN(neural networks) and clustering method as a scheme of off-line PD(partial discharge) diagnosis which occurs at the stator coil of traction motor. To acquire PD data, three defective models are made. PD data for classification were acquired from PD detector. And then statistical distributions are calculated to classify model discharge sources. These statistical distributions were applied as input data of two classification tools, BP(Back propagation algorithm) and ANFIS(adaptive network based fuzzy inference system) pre-processed FCM(fuzzy c-means) clustering method. So, classification rate of BP were somewhat higher than ANFIS. But other items of ANFIS were better than BP; learning time, parameter number, simplicity of algorithm.

• 한국기계기술학회지
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• 제20권6호
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• pp.906-911
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• 2018

This study was conducted to develop an efficient high performance range hood and exhaust system for quickly discharging flue gas, smoke, and odor generated when food is cooked in the kitchen, and the following results were obtained. Reverse current rate of 1.53 m/s of the range exhaust system was improved to achieve the inlet speed of 0.3 m/s or less. An efficient range system was constructed by improving the hood exhaust flow by 5.6 m/s at the existing 4.5 m/s.

• 스마트미디어저널
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• 제13권2호
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• pp.85-94
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• 2024

Artificial Intelligence of Things (AIoT), which combines AI and the Internet of Things (IoT), has recently gained popularity. Deep neural networks (DNNs) have achieved great success in many applications. Deploying complex AI models on embedded boards, nevertheless, may be challenging due to computational limitations or intelligent model complexity. This paper focuses on an AIoT-based system for smart sewing automation using edge devices. Our technique included developing a detection model and a decision tree for a sufficient testing scenario. YOLOv5 set the stage for our defective sewing stitches detection model, to detect anomalies and classify the sewing patterns. According to the experimental testing, the proposed approach achieved a perfect score with accuracy and F1score of 1.0, False Positive Rate (FPR), False Negative Rate (FNR) of 0, and a speed of 0.07 seconds with file size 2.43MB.

• 대한치과보철학회지
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• 제43권2호
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• pp.158-175
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• 2005

Statement of problem. Every effort has been continually made to obtain objectivity in measuring the longevity of fixed restorations, such as by establishing unified judgement standard for deciding success and adopting statistical method that analyzes the data of successful and failed cases at the same time. In Korea, however desired level of development has not to be made in this field yet. Purpose. This study, adopting California Dental Association (CDA) quality evaluation system, established objective standard for deciding success, and inferred the longevity of fixed restorations and their failure analysis through adopting Kaplan-Meier survival analysis. Material and method. In order to assess the longevity of flxed restorations serviced in Korea and causes of failure, a total of 1109 individuals (aged 15-74, 716 women and 393 men loaded with 2551 unit fixed restorations, and 1934 abutments) who lived in Kyung-In Province were examined and the findings were as follows : Results. 1. Length of service of fixed restorations serviced in Korea was 6.86$\pm$0.15 yr (mean), 5.5 yr (median), and the rate of success was 65.82% in 5 year survival, and 21.15% in 10 year survival. 2. When there was patient's need for replacing old prosthetics, longevity of fixed restorations was 7.51$\pm$0.27 yr (mean), 7 yr (median), and the rate of success was 61.08% in 5 year survival, and 17.57% in 10 year survival. 3. Longevity of fixed restorations was longest in the over-sixty age group(9.21$\pm$0.66) and that of the teen age group(3.39$\pm$0.28) was shortest (p<0.05). 4. Longevity of fixed restorations of women (7.38$\pm$0.18 years) was longer than that of men (6.00$\pm$0.26) (p<0.05). 5. As for the provider factor (such as unlicensed performers, university hospitals, and private clinic), there was no statistically significant difference in longevity of fixed restorations. 6. Defective margin (34.78%). periodontal disease (12.15%), periapical involvement (11.73%), was the most frequent causes of failure and poor esthetics group showed the longest life above all (p<0.05). Actual frequent causes of failure after removing old prosthetics were defective margin, periapical involvement, periodontal disease and uncemented restoration. In 75.67% of the cases, abutment state after removing old prosthetics was good enough for loading another prosthetics. 7. There was found to have statistically significant influence between longevity of single crown (6.35$\pm$0.20 yr) and that of 3 unit fixed restorations (7.60$\pm$0.30 y) (p<0.05). In each case the most frequent cause of failure was defective margin. 8. The number of cantilever pontic, pontic/abutment ratio, oral hygiene status were found to have no statistically significant influence on longevity of fixed restorations in all groups (p>0.05). 9. Longevity of fixed restorations made of non precious metal was longest (9.60$\pm$0.40 yr) semi precious and precious trailing behind(p<0.05). 10. Group function group (37.04%) and partial group function group (44.62%) were predominant in frequency but showed no correlation between them and among different types of occlusal plane and different types of occlusal surface (p>0.05). 11. Longevity of fixed restorations was longest in the centric interference group(9.35$\pm$0.62) (p<0.05) among different types of occlusal interference. Conclusion. We found that longevity of fixed restorations serviced in Korea is affected by age, gender and type of material, and that most frequent cause of failure is defective margin. In order to assess the accurate longevity of axed restorations, unified research design. overcoming inter-observer difference and establishing the objective research items are needed. Furthermore, it is thought that prospective approach through thorough study and regular follow-ups is needed just from the start of research. Nationwide detailed studies on length of service of fixed restorations manufactured in Korea are hoped to be conducted hereafter.

• 한국가축번식학회지
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• 제19권1호
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• pp.35-41
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• 1995

본 연구는 형질전화우의 생산성 제고를 위한 일환으로서 새로운 기법인 retrovirus vector system의 이용성을 검토하고자 실시하였다. Retrovirus-producing cell은 미세주입법을 이용하여 체외생산된 1.5일(1~4-세포기) 수정란의 위란강에 주입(5~10 cells/embryo) 되었으며, 이때 사용된 retrovirus-producing cell line은 Gibbon ape leukemia virus (GaLV) envelope protein에 encapsidation되어 replication-defective retrovirus를 분비하도록 제작되었다. 주입된 유전자의 표지유전자로서 E. coli LacZ 유전자를 사용하였으며, X-gal 염색법은 발달이 유도된 상실배와 배반포 단계에 실시하여 LacZ 유전자의 발현 유무를 확인하였다. 이 실험의 결과를 요약하면 다음과 같다. 1. Virus의 infectivity를 높이기 위해 사용된 polybrene의 최저농도는 5$\mu\textrm{g}$/ml이었다. 2. Retrovirus-producing cell이 주입된 1.5일 수정란의 상실배기와 배반포기로의 발달율은 29%였다. 3. 이 때의 LacZ+ 발현율은 21%였다. 4. 본 실험에 사용된 retrovirus-producing cell은 replication-competent retroviruses를 생산해 내지않는다는 것을 확인할 수 있었다.