• Journal of Life Science
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• v.13 no.6
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• pp.933-942
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• 2003

CoenzymeQ is a quinone derivative with a long isoprenoid side chain. It transports electrons in the respiratory chain located in the inner mitochondrial membrane of eukaryotes and the plasma membrane of prokaryotes. It also functions as an antioxidant. Saccharomyces cerevisine coq mutants, that are deficient coenzyme Q biosynthesis fail to aerobically grow. They are not able to grow on non-fermentable carbon sources, such as glycerol, either The putative $coq^{-7}$ gene involved in coenzyme Q biosynthesis of Neurospora crassa was cloned and used for complementation of S. cerevisiae coq7 mutant. The predicted amino acid sequence of N. crassa COQ7 showed about 58% homology with Coq7p of S. cerevisiae. The growth rate of S. cerevisiae $coq^7$ mutant transformed with the N. crassa $coq^{-7}$ gene was restored to the wild-type level. The complemented 5. cerevisiae strain was able to grow with glycerol as a sole carbon source and showed less sensitivities to linolenic acid, a polyunsaturated fatty acid.

• Korean Journal of Microbiology
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• v.40 no.2
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• pp.73-80
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• 2004

Coenzyme Q is a quinone derivative that acts as a lipid electron carrier in the respiratory chain located at mito-chondrial inner membrane in eucaryotes or plasma membrane in procaryotes and also functions as antioxidant. A putative Neurospora crassa coq-4 gene was cloned and functionally expressed in Saccharomyces cerevisiae coq4 mutant. Complemented S. cerevisaie mutant strain was able to produce coenzyme $Q_{6}$ and showed a normal growth rate. They also showed less sensitivities to polyunsaturated fatty acids such as linoleic acid or linolenic acid. The predicted sequence of N. crassa COQ4 is consisted of 347 amino acids with a molecular mass of 39.7 kDa and showed 35% identity and 52% similarity with that of S. cerevisiae.

• Proceedings of the Korean Society of Life Science Conference
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• 2003.05a
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• pp.57-57
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• 2003

• Journal of Korean Society for Quality Management
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• v.44 no.4
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• pp.713-733
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• 2016

Purpose: The primary objective of this case study is to establish a COQ(Cost of Quality) management system for power generation industries. Key topics of this study include collecting COQ elements, their classifications, COQ computation formula, and determining COQ improvement projects. Results: A comprehensive set of COQ elements have been isolated for electric power generation companies. The COQ elements were classified in such a way that they could be managed according to the PAF model as well as the SIPOC diagram. This study showed that a systematic approach could be established for monitoring the COQ elements and using them in the process of improving quality competitiveness. Methods: The PAF(Prevention-Appraisal-Failure) model has been employed in the process of collecting COQ elements for a power generation company. All the cost of quality elements were first examined through an extensive review of articles and books in the field of quality. The cost elements were then refined and augmented by conducting a comparative study with international standards. The COQ elements have been verified by a group of quality managers and classified according to both the PAF model and the SIPOC diagram for better understanding in the entire organization. An improvement strategy has been also proposed by using a typical COQ level of power generation companies. Conclusion: The conventional PAF model was used in establishing a COQ management system for power generation industries. This case study illustrates the procedure about identification, classification and computation of quality costs, including selection of improvement projects. The system can be used not only for observing the current state of cost elements related to quality, but also for planning an improvement strategy using the ratio of cost classification.

• Journal of KIISE:Software and Applications
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• v.37 no.1
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• pp.54-59
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• 2010

Special-purpose microcontrollers PLCs have been widely used in the area of industrial automation. For the research of analysis and verification for PLC programs, first of all we have to specify formal sematics of PLC programming languages. This paper defines formally the operational semantics of LD language. After we transform the graphical language LD into its textual representation Symbolic LD, we give semantics of Symbolic LD since LD language is a graphical language. This paper defines the natural sematics of Symbolic LD and formalizes it in Coq proof assistant.

• Journal of the Korea Safety Management & Science
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• v.17 no.1
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• pp.321-335
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• 2015

This study introduces the methods to apply and develop the integrated Cost of Quality (COQ) and Time-Driven Activity-Based Costing (TDABC) model for seeking not only quality improvement but also reduction of overhead cost. Inefficient and uneconomical COQ activities can be identified by using time driver which also maximizes the quality improvement for Prevention-Appraisal- Failure (PAF) quality costs. In contrast, reduction of the indirect cost of unused capacity resource using Quality Cost Capacity Ratio (QCCR) of TDABC minimizes overhead cost for COQ activities. In addition, linkage between Overall Equipment Effective (OEE) and Time Driver develops the integrated system of Total Productive Maintenance (TPM) and TDABC model. Lean OEE maximizes when an Unused Time (UT) of TDABC that are TPM losses and lean wastes reduces whereas the TPM Cost Capacity Ratio (TCCR) of TDABC minimizes indirect cost for non-value added TPM activities. Numerical examples are derived to better understand the proposed COQ/TDABC model and TPM/TDABC model from this paper. From the proposed model, process mapping and time driver of TDABC are known to lessen indirect cost from general ledger of comprehensive income statement with a better quality innovation and improvement of equipment.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.18 no.11
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• pp.1626-1634
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• 1993

In this paper we propose a coding scheme which combines source codes and error correcting codes in order to be robus to channel noise. One of the coding schemes that take into account both the source and the channel is the channel optimized quantizer (COQ) which simultaneously minimizes quantization noise and the noise due to channel errors. This paper deals with the problem of combining channel optimized quantizers with ECC to build an improved system. To be specific, we computed the performance of an n bit COQ and that of an n-1 bit COQ followed by an (n-1)/n punctured convolutional code. From this result whether or not the ECC are selected is determined by the number of allocated bits and the channel bit error rate. These results are applied to the image trans-mission method using DCT, and the system performances are evaluated.

• International Journal of Quality Innovation
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• v.8 no.1
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• pp.87-98
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• 2007

A COQ model plays an important role in the total quality cost survey. Based on the methodology of continuous quality improvement, a dynamic COQ model for different quality level is developed in this paper. A quality level is defined by Six Sigma level that can be measured by two indicators. The relationships among the four major quality costs are analyzed. Finally, the curves of total quality costs for different quality level are presented.

• IE interfaces
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• v.24 no.2
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• pp.128-138
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• 2011

This research proposes a resource allocation model of Data QC (Quality Control) activities using COQ (Cost of Quality). The model has been developed based on a series of research efforts such as COQ classifications, weight determination of Data QC activities, and an aggregation approach between COQ and Data QC activities. In the first stage of this research, COQ was divided into the four typical classifications (prevention costs, appraisal costs, internal failure costs and external failure costs) through the opinions from five professionals in Data QC. In the second stage, the weights of Data QC activities were elicited from the field professionals. An aggregation model between COQ and Data QC activities has been then proposed to help the practitioners make a resource allocation strategy. DEA (Data Envelopment Analysis) was utilized for locating efficient decision points. The proposed resource allocation model has been validated using the case of Korea national defense information system. This research is unique in that it applies the concept of COQ to the data management for the first time and that it demonstrates a possible contribution to a real world case for budget allocation of national defense information.

• Proceedings of the Safety Management and Science Conference
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• 2000.05a
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• pp.423-426
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• 2000

본 연구에서는 $6\sigma$의 DMAIC, Ford의 8D 프로세스, 품질기술 분임조 개선활동, PDCA, S-PPM, 100PPM 개선활동, Feigenbaum, Juran 등이 제시한 다양한 문제해결 또는 품질, 공정, 경영혁신 등의 기법을 상호 비교하여 통합(Fusion), 공유(Sharing)할 수 있는 방안을 제안하며, ISO 9001:1994, 2000에 의한 품질시스템, 품질코스트(COQ)와 의 통합 구축방안을 제안한다.