• Title/Summary/Keyword: Optimal Life Time

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A Software Reliability Cost Model Based on the Shape Parameter of Lomax Distribution (Lomax 분포의 형상모수에 근거한 소프트웨어 신뢰성 비용모형에 관한 연구)

  • Yang, Tae-Jin
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.9 no.2
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    • pp.171-177
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    • 2016
  • Software reliability in the software development process is an important issue. Software process improvement helps in finishing with reliable software product. Infinite failure NHPP software reliability models presented in the literature exhibit either constant, monotonic increasing or monotonic decreasing failure occurrence rates per fault. In this study, reliability software cost model considering shape parameter based on life distribution from the process of software product testing was studied. The cost comparison problem of the Lomax distribution reliability growth model that is widely used in the field of reliability presented. The software failure model was used the infinite failure non-homogeneous Poisson process model. The parameters estimation using maximum likelihood estimation was conducted. For analysis of software cost model considering shape parameter. In the process of change and large software fix this situation can scarcely avoid the occurrence of defects is reality. The conditions that meet the reliability requirements and to minimize the total cost of the optimal release time. Studies comparing emissions when analyzing the problem to help kurtosis So why Kappa efficient distribution, exponential distribution, etc. updated in terms of the case is considered as also worthwhile. In this research, software developers to identify software development cost some extent be able to help is considered.

Occurrence of the Entomopathogenic Fungus Zoophthora radicans (Entomophthorales: Entomophthoraceae) in Jeollabuk-do, Korea (전라북도에서 곤충 병원성 곰팡이 Zoophthora radicans (Entomophthorales: Entomophthoraceae)의 발생)

  • Choi, Seonu;Kim, Juhee;Seo, Kyoungwon;Moon, Younghun;Lee, Gongjun;Lee, Changkyu;Kim, Jaesu;Kim, Jinho
    • Korean journal of applied entomology
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    • v.56 no.2
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    • pp.195-201
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    • 2017
  • The entomopathogenic fungus Zoophthora radicans (Entomophthorales: Entomophthoraceae) was found to infect Cnaphalocrocis medinalis, Plutella xylostella, Myzus persicae and one unidentifed species. Samples of the fungus were collected from three areas (Jinan, Gimje, and Iksan) in Jeollabuk-do, Korea. Infected insects appeared in July and September, during which time population infection rate of Z. radicans on C. medinalis reached up to 46%. Zoophthora radicans hyphal bodies are rod-like to hyphoid, and primary conidia are bullet-shaped to long ovoid. The fungus was isolated from the surfaces of larvae and cultured in Sabouraud dextrose agar with yeast extract (SDAY). The optimal temperature range for mycelial growth was $20{\sim}28^{\circ}C$. Mycelium growth on SDAY supplemented with egg yolk and milk (SDAY-EM) was higher than on SDAY alone. Zoophthora radicans may play an important role in controlling insect population density using naturally induced epizootics.

A 2-D Location Determination Model of Buried Persons in Collapsed Shape using Optimal Wireless Communication Technology (최적 무선통신 기술을 활용한 붕괴지형 매몰자의 2차원 매몰위치 결정 모델)

  • Moon, Hyoun-Seok;Lee, Woo-Sik;Lee, Gun-Woo;Han, Dong-Soo
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.16 no.12
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    • pp.8879-8888
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    • 2015
  • When the disaster like earthquake in urban area occur, due to the collapse accidents for subway, tunnel space with buildings or underground area, enormous property and human damage are happened. Specially, since it is difficult to identify survived status of humans within collapsed debris and accurately buried locations of the humans, inputs of considerable time and manpower for rescuing them are required. Besides, secondary damage can be occurred by additional collapses. The aim of this study is to propose a stochastic location positioning method that enables to provide aid information by determining locations of mobile devices for buried persons in 2-D plane using wireless communication technologies. This study selected a detection method for buried persons based on Wi-Fi signal, and identified characteristics of signal strengths by distance unit. Using these methods, a stochastic location detection model in 2-D plane was built. It is expected that this technology will be utilized as a core technology that can protects safety and human life of the public by providing data for rescuing quickly buried persons in cases of national disasters for future.

Assessment of location of the air quality monitoring stations according to the analysis of wind sector division in Pohang (포항지역의 바람권역 분석에 따른 대기측정망 위치 평가)

  • Jung, Jong-Hyeon;Lee, Hyung-Don;Shon, Byung-Hyun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.13 no.4
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    • pp.1931-1938
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    • 2012
  • This study evaluated whether the installed location of air quality monitoring stations is at an optimal level in an effort to improve the health and environmental quality of the surrounding areas of the Pohang Steel Complex. As a result of analyzing the atmospheric flow field, it was found that the location of air quality monitoring stations was acceptable in case of Daesong-myeon(The 1st Division of Local Wind Sector) and Jukdo-dong(The 3rd Division of Local Wind Sector). However, the air quality monitoring stations installed at Daedo-dong and Jukdo-dong is judged to have made an overlapped measurement because the stations existed at the Division of the same Wind Sector. Accordingly, this study suggests that the further air quality monitoring stations should be additionally installed at Buk-gu areas of Pohang where more than 50% of the population of Pohang is living presently. As a result of the analysis of air contaminant concentration distribution, the Jangheung-dong area showed higher concentration distribution than other areas in case of $PM_{10}$ while the Daesong-myeon area showed a comparatively higher concentration distribution in case of $O_3$. Conclusively, this study indicates that it is high time to prepare an aggressive management of $PM_{10}$ and $O_3$ which causes a harmful impact on the life and health of the residents of the target areas.

Doing Science through the Project-Based Science Program (프로젝트형 탐구학습을 통한 영재들의 과학하기)

  • 조한국;한기순;박인호
    • Journal of Gifted/Talented Education
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    • v.11 no.3
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    • pp.23-44
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    • 2001
  • In the current classrooms a teacher has been merely able to inculcate the procedural knowledge of how-and-what. In doing so, however, we lose sight of the essence of "doing science."Though desire of the gifted children is qualitatively different from that of normal children, it is an undesirable reality that we have not developed sufficient researches and programs in conformity with the necessary desire and demand of the gifted children. Curriculum for gifted children in the domain of science necessitates markedly the specializations for the specific areas of the contents, the processes, and the products of studies. In an effort to provide the optimum learning experience for the gifted, this paper deals with the development of project-and-discovery-based science program, its method of application to the real field of education, and its effect, however limited and partial that effect may be. What this study has found are the following: on the one hand, the students acquired and developed the higher levels of thinking when they were under the influence of project-and-discovery-based science program that dealt with concrete real-world problems and issues; on the other, the students were capable of solving creatively the complex and real problems through small group activities. This study also suggests the possible implications of project-and-discovery-based science program: the students can not only learn the contents of study but also apply them creatively; the students can cultivate critical thinking skills that can be a fundamental base for a life-time leaner; the students can naturally acquire the abilities of communication and coordination. Project-and-discovery-based program is currently used in the various disciplines. However, the field of gifted education does not yet implement this type of program. So the overall contribution of this study is to show the successful implementation of project-and-discovery-based science program in developing optimal teaming experience for gifted children in the domain of science, since this type of study is most compatible with the characteristic of the gifted children. children.

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Differences in Functional Materials between White and Black Rice Varieties

  • Lee, Chae Young;Park, Jae Seong;Lee, Hee Du;Choi, Ye Seul;Hong, Seong Taek;Hong, Eui Yon;Lee, Yun Sang;Kim, In Jae;Woo, Sun Hee
    • Proceedings of the Korean Society of Crop Science Conference
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    • 2017.06a
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    • pp.368-368
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    • 2017
  • Rice is the world's three major crops that is the staple food of Asian. Japonica type rice is consumed in Korea. Rice cultivation area decreases steadily. That is affected by decrease of the farm income with the inventory of 1.7 million tons, which is 2 to 3 times more than the optimal amount due to the decrease in the consumption of rice per person and cultivate high yield varieties. In recent years, as income level has improved, interest in health has been high and consumption for health food has been steadily increasing. For health food, rice is added by adding grains such as millet, sorghum, oats, beans and colored rice rather than white rice. In 1997, RDA(Rural Development Administration) developed black rice 'Heuknambyeo', and then 20 varieties were bred until 2017. In CBARES(Chungbuk Agricultural Research and Extension Services), we have developed new rice varieties 'Cheongpungheukchal' in 2010, 'Cheongpungheukhyangchal' in 2014, 'Cheongpungheukchal' is high in farming preference because of high yield. Black rice has high content of GABA and water-soluble phenol, DPPH radical scavenging activity, and consumers are interested in the function in the body. Therefore, functional and antioxidant activities(anthocyanin, total polyphenol, ${\alpha}-glucosidase$ inhibition) and antioxidant activities(ABTs, DPPH) were analyzed by comparing white and black rice. Testing varieties are 'Chucheongbyeo', best quality cultivars 'Daebo' and 'Samgwang' as white rice which are cultivated much in Chungbuk area, and black rice are 10 varieties including 'Cheongpungheukchal', 'Cheongpungheukhyangchal', 'Josaengheukchal' and so on. It has transplanted on 25th May, at CBARES research paddy by 100% fertilizer recommendation rate. Harvesting time was 50 days after heading by varieties, and has researched growth properties, yield and yield components, functional and antioxidant activities. Anthocyanin content was not measured because there was no pigmented in white rice, the highest value of anthocyanin content was 'Shintoheukmi' and in the range of 125.6~249.6mg/100g by black rice varieties. Total polyphenol content was high 'Cheongpungheukchal' and 'Shintoheukmi' and in the range of 96.68~244.34 mg/100g in black rice, white rice lower than blackish rice at 19.84~22.51mg/100g. ${\alpha}-glucosidase$ inhibition was high 'Cheongpungheukchal', 'Cheongpungheukhyangchal' and 'Shintoheukmi' in the rage of 75.87~98.85% by black rice varieties, especially 'Samgwang' was 80.75% and the other white rice was higher than 58~68%.

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An Empirical Study on Linux I/O stack for the Lifetime of SSD Perspective (SSD 수명 관점에서 리눅스 I/O 스택에 대한 실험적 분석)

  • Jeong, Nam Ki;Han, Tae Hee
    • Journal of the Institute of Electronics and Information Engineers
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    • v.52 no.9
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    • pp.54-62
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    • 2015
  • Although NAND flash-based SSD (Solid-State Drive) provides superior performance in comparison to HDD (Hard Disk Drive), it has a major drawback in write endurance. As a result, the lifetime of SSD is determined by the workload and thus it becomes a big challenge in current technology trend of such as the shifting from SLC (Single Level Cell) to MLC (Multi Level cell) and even TLC (Triple Level Cell). Most previous studies have dealt with wear-leveling or improving SSD lifetime regarding hardware architecture. In this paper, we propose the optimal configuration of host I/O stack focusing on file system, I/O scheduler, and link power management using JEDEC enterprise workloads in terms of WAF (Write Amplification Factor) which represents the efficiency perspective of SSD life time especially for host write processing into flash memory. Experimental analysis shows that the optimum configuration of I/O stack for the perspective of SSD lifetime is MinPower-Dead-XFS which prolongs the lifetime of SSD approximately 2.6 times in comparison with MaxPower-Cfq-Ext4, the best performance combination. Though the performance was reduced by 13%, this contributions demonstrates a considerable aspect of SSD lifetime in relation to I/O stack optimization.

The Algicidal Activity of Pseudoalteromonas sp. NH-12 against the Toxic Dinoflagellate Alexandrium catenella (유독성 와편모류 Alexandrium catenella에 대한 Pseudoalteromonas sp. NH-12의 살조능)

  • Jeoung, Nam-Ho;Son, Hong-Joo;Jeong, Seong-Yun
    • Korean Journal of Environmental Agriculture
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    • v.31 no.2
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    • pp.175-184
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    • 2012
  • BACKGROUND: The aim of this study was to isolate and identify algicidal bacterium that tends to kill the toxic dinoflagellate Alexandrium catenella, and to determine the algicidal activity. METHODS AND RESULTS: Among of four algicidal bacteria isolated in this study, NH-12 isolate was the strongest algicidal activity against A. catenella. NH-12 isolate was identified on the basis of biochemical characteristics and analysis of 16S rRNA gene sequences. The isolate showed 97.67% homology with Pseudoalteromonas prydzensis ACAM $620^T$ (U85855), and was designated Pseudoalteromonas sp. NH-12. The optimal culture conditions of this isolate were $25^{\circ}C$, initial pH 8.0, and 3.0% (w/v) NaCl concentration. The algicidal activity of NH-12 was significantly increased to maximum value in the late of logarithmic phase of bacterial culture. As a result of 'cell culture insert' experiment, NH-12 is assumed to produce secondary metabolites, as an indirect attacker. When 10% culture filtrate of NH-12 was applied to A. catenella, over 99% of algal cells were destroyed within 24 h. In addition, the killing effects were increased in dose and time dependent manners. CONCLUSION(S): Taken together, our results suggest that Pseudoalteromonas sp. NH-12 could be a candidate for controlling of toxic algal blooms.

A Study on Parameters Estimation of Storage Function Model Using the Genetic Algorithms (유전자 알고리듬을 이용한 저류함수모형의 매개변수 추정에 관한 연구)

  • Park, Bong-Jin;Cha, Hyeong-Seon;Kim, Ju-Hwan
    • Journal of Korea Water Resources Association
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    • v.30 no.4
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    • pp.347-355
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    • 1997
  • In this study, the applicability of genetic algorithms into the parameter estimation of storage function method for flood routing model is investigated. Genetic algorithm is mathematically established theory based on the process of Darwinian natural selection and survival of fittest. It can be represented as a kind of search algorithms for optima point in solution space and make a reach on optimal solutions through performance improvement of assumed model by applying the natural selection of life as mechanical learning province. Flood events recorded in the Daechung dam are selected and used for the parameter estimation and verification of the proposed parameter estimation method by the split sample method. The results are analyzed that the performance of the model are improved including peak discharge and time to peak and shown that the parameter Rsa, and f1 are most sensitive to storage function model. Based on the analysis for estimated parameters and the comparison with the results from experimental equations, the applicability of genetic algorithm is verified and the improvements of those equations will be used for the augmentation of flood control efficiency.

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Growth Rate of Transgenic Pigs and Size of Pig Hearts for Xenotransplantation to Cynomolgus Monkey

  • Ock, Sun A;Oh, Keon Bong;Hwang, Seongsoo;Lee, Jungkyu;Kim, Youngim;Moon, Sun-Woung;Kwon, Dae-Jin;Yun, Ik Jin;Park, Eungwoo
    • Journal of Embryo Transfer
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    • v.29 no.4
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    • pp.333-337
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    • 2014
  • To compensate for the critical shortage of human organs for allotransplantation, xenotransplantation studies using genetically modified pigs are being performed in Korea. Two types of pigs that are used are ${\alpha}1,3$-galactosyltransferase gene knockout (GalT KO) pigs and GalT KO+hCD46 (human complement regulatory protein) pigs. The present study measured the gestation time, birth weight, daily growth rate, and heart weight of both kinds of transgenic minipigs. The gestation period for both types of pigs was 117~119 days. There was no difference in the body weight of GalT KO (-/+) and GalT KO (-/-) piglets, but GalT KO+hCD46 ($-^{hCD46+}/+$) pigs were significantly heavier at birth than were GalT KO+hCD46 ($-^{hCD46+}/-^{hCD46+}$) pigs. During the first 10 weeks of life, the daily weight gain of GalT KO+hCD46 ($-^{hCD46+}/-^{CD46+}$) piglets, which are considered the optimal type for xenotransplantation, was 0.19 kg. The weight of hearts from GalT KO piglets up to two months of age was affected more by body weight than by age. Transgenic pigs showed no differences in gestation period or reproductive ability compared with normal pigs. These results comprise basic data that may be used in xenotransplantation studies and transgenic animal production in Korea.