• The KIPS Transactions:PartD
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• v.8D no.6
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• pp.835-842
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• 2001

We propose a software-reliability growth model incoporating the amount of testing effort expended during the software testing phase. The time-dependent behavior of testing effort expenditures is described by a Weibull curve. Assuming that the error detection rate to the amount of testing effort spent during the testing phase is proportional to the current error content, a software-reliability growth model is formulated by a nonhomogeneous Poisson process. Using this model the method of data analysis for software reliability measurement is developed. After defining a software reliability, we discuss the relations between testing time and reliability and between duration following failure fixing and reliability are studied in this paper. The release time making the testing cost to be minimum is determined through studying the cost for each condition. Also, the release time is determined depending on the conditions of the specified reliability. The optimum release time is determined by simultaneously studying optimum release time issue that determines both the cost related time and the specified reliability related time.

• Journal of Mushroom
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• v.9 no.4
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• pp.161-165
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• 2011

Small scale mushroom growers take a lot of the costs in the bottle cultivation than the large scale growers. Therefore, they are not competitive in the market. Mushroom cultivation in small scale mushroom farm is labor-intensive and this experiment was carried out to establish the method for the cultivation of various kinds of mushrooms together under the similar conditions in the production system. As a result, the common medium were selected based on the growing conditions of Pleurotus eryngii and Agrocybe cylindracea, and the level of medium moisture content were studied. The results were shown below. When the medium in the input stage for bottle cultivation was filled by using automatic machine, the range of the three state rates in the bottle is different depending on ingredients and the mixing ratio. The optimum moisture content of the medium for some mushroom production was a different trend based on the medium cluster of the raw materials. The optimum moisture content for P. eryngii in the medium was 70% (douglas fir sawdust, rice bran or sawdust, dried bean curd refuse). In the medium containing douglas fir sawdust, wheat bran was 65%, and the medium including douglas fir sawdust, wheat bran, dried bean curd refuse was 67%. The optimum moisture content of the above three media for A. cylindracea was 70%. The suitable medium for the bottle cultivation of P. eryngii was selected as douglas fir sawdust 75%, wheat bran 20%, dried bean curd refuse 5%, and moisture content 67%. The medium of A. cylindracea was selected as douglas fir sawdust 75%, wheat bran 25%, and moisture content 70%. The suitable medium for bottle cultivation of P. eryngii and A. cylindracea was shown as douglas fir sawdust 75%, rice bran20%, dried bean curd refuse 5%, and 70% moisture content to be used as a common medium of the growing. The incubation period, primordial formation, and growth environment conditions of P. eryngii and A. cylindracea were a similar trend. Therefore, the small scale farmers of P. eryngii can cultivate A. cylindracea together with P. eryngii.

• Journal of the Korean Ceramic Society
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• v.28 no.6
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• pp.488-494
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• 1991

In this study, the effects of catalyst and DCCA content were investigated in order to determine the optimum conditions of monolithic silica gel formation through sol-gel process. Formamide, oxalic acid, glycerol and dimethylformamide are used as DCCA. To observe the phenomena in drying and heat-treating of gels, we examined structural exchange of gels using FT-IR, TG-DTA and XRD. Monolithic gels were obtained by adding formamide and dimethylformamide as DCCA. According to the heat treatment schedule, silica glass is prepared by heat-treatment up to 1050$^{\circ}C$.

• Proceedings of the Korea Concrete Institute Conference
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• 1994.10a
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• pp.393-398
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• 1994

Roller compacted concrete(RCC) has been attracted due to its growing application to pavement concrete construction. In this study optimum mixing formation of RCC was explored and characterized its properties forcusing on reducing try and error for actual application to construction of pavement. The concrete used for roller compacted concrete pavement (RCCP) has very low water content per unit volume, so that it develops early high strength. This high early strength development makes pavement constructed open early. This concrete also showed very reduced crack formed on the surface because of expensive cement.

• Proceedings of the Korea Concrete Institute Conference
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• 2002.05a
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• pp.195-200
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• 2002

In this paper, the effects of type and content of antifreezer on the frost resistance of concrete at early age were investigated. For this purpose, 4 types of antifreezer and 2 types of superplasticizer were selected, and based on the strength recovery ratio, the frost resistance of concrete was estimated. The optimum concrete mixes were also produced when the curing temperatures were -5 and -10$\{circ}{c}$.

• Journal of the Korean Society of Tobacco Science
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• v.6 no.2
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• pp.215-219
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• 1984

This experiment was conducted to investigate the effect of physical and chemical characteristics of lower grade tobacco with treatment of ozone. In ozonization of low grade tobacco, optimum moisture was 20 percentage, and decrease ratio of content of tobacco leaf was 30 percentage in nicotine , 15.9 percentage in total volatile base, 10.5 percentage in petroleum-ether-extract, 29.5 percentage in solanesol, and decrease ratio of cigarette smoke composition was 31 percentage in nicotine, 6.08 percentage in tar.

• YAKHAK HOEJI
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• v.15 no.2
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• pp.64-75
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• 1971

Optimum condition for cultivation of Anemarrhena asphodeloides B$_{UNGE}$ and seasonal variation of saponin and sapogenin contents in the rhizome were investigated. It is confirmed that the best harvest time is 3rd year. Average contents of saponin in rhizome was 8.5% and 5.0%, in fibrous roots, being highest in winter. The facotrs of saponin content variation were seemed to be temperature and humidity. It was also proved that asphonin was the mixture of timosaponin A-III, timosaponin A-I and mangiferin. Mangiferin and isomangiferin were isolated from the flower.

• Proceedings of the Korean Society of Crop Science Conference
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• 1996.10a
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• pp.56-57
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• 1996

• Proceedings of the Korean Society of Crop Science Conference
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• 2004.04a
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• pp.184-185
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• 2004

• Textile Coloration and Finishing
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• v.9 no.6
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• pp.74-78
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• 1997

This study was performed to obtain the basic data of the effect of antimicrobic finishing on chrome-tanned leather for apparel. This study was to examine the effect of conditions of antimicrobic finishing on content of antimicrobic agents in the specimen by analysis and on the antimicrobic activity of specimens by means of shake flask test. The optimum conditions of antimicrobic finishing were found to be ; the concentration of Si-QAC-0.5%(o.w.f.), treating time-30minute, and drying method-air drying.