• Title/Summary/Keyword: 탐색적연구

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The Study on the Education and Training for the Personnel in the Military Acquisition Field in US (미국 국방획득인력의 교육·훈련체계 및 관련동향)

  • Kim, Myunghyun;Lee, Youngwoo;Kim, Kyoungrok
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.3
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    • pp.223-229
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    • 2020
  • The current technological advances are changing the way people live. In the history of war in the past, nations or people with an edge in military science and technology have always been the victor. The emergence of new technologies not only alters war patterns drastically but also affects military operational concepts and organizational systems. As the paradigm of the security environment changes, developed countries are investing heavily in defense R & D for their security. Therefore, the importance of professionalism of the defense acquisition personnel who perform their tasks from the exploration and development of weapon systems to mass production, deployment, and logistics support cannot be overemphasized. In the United States, an advanced country in this field, to improve the work efficiency of acquisition personnel in the defense field, the Directive of Ministry of Defense issued a law on education and training career development for personnel in 1990. The present study refers to related materials, such as the Desk Guide for the main education requirements for the US acquisition personnel in the military field, which contributes to the improvement of the workforce of the acquired manpower after the systematic education system.

A Study on GA-based Optimized Polynomial Neural Networks and Its Application to Nonlinear Process (유전자 알고리즘 기반 최적 다항식 뉴럴네트워크 연구 및 비선형 공정으로의 응용)

  • Kim Wan-Su;Lee In-Tae;Oh Sung-Kwun;Kim Hyun-Ki
    • Journal of the Korean Institute of Intelligent Systems
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    • v.15 no.7
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    • pp.846-851
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    • 2005
  • In this paper, we propose Genetic Algorithms(GAs)-based Optimized Polynomial Neural Networks(PNN). The proposed algorithm is based on Group Method of Data Handling(GMDH) method and its structure is similar to feedforward Neural Networks. But the structure of PNN is not fixed like in conventional neural networks and can be generated in a dynamic manner. As each node of PNN structure, we use several types of high-order polynomial such as linear, quadratic and modified quadratic, and it is connected as various kinds of multi-variable inputs. The conventional PNN depends on the experience of a designer that select the number of input variables, input variable and polynomial type. Therefore it is very difficult to organize optimized network. The proposed algorithm leads to identify and select the number of input variables, input variable and polynomial type by using Genetic Algorithms(GAs). The aggregate performance index with weighting factor is proposed as well. The study is illustrated with tile NOx omission process data of gas turbine power plant for application to nonlinear process. In the sequel the proposed model shows not only superb predictability but also high accuracy in comparison to the existing intelligent models.

Optimization of Z-R relationship in the summer of 2014 using a micro genetic algorithm (마이크로 유전알고리즘을 이용한 2014년 여름철 Z-R 관계식 최적화)

  • Lee, Yong Hee;Nam, Ji-Eun;Joo, Sangwon
    • Journal of the Korean Institute of Intelligent Systems
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    • v.26 no.1
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    • pp.1-8
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    • 2016
  • The Korea Meteorological Administration has operated the Automatic Weather Stations, of the average 13 km horizontal resolution, to observe rainfall. However, an additional RADAR network also has been operated in all-weather conditions, because AWS network could not observed rainfall over the sea. In general, the rain rate is obtained by estimating the relationship between the radar reflectivity (Z) and the rainfall (R). But this empirical relationship needs to be optimized on the rainfall over the Korean peninsula. This study was carried out to optimize the Z-R relationship in the summer of 2014 using a parallel Micro Genetic Algorithm. The optimized Z-R relationship, $Z=120R^{1.56}$, using a micro genetic algorithm was different from the various Z-R relationships that have been previously used. However, the landscape of the fitness function found in this study looked like a flat plateau. So there was a limit to the fine estimation including the complex development and decay processes of precipitation between the ground and an altitude of 1.5km.

Production and Separation of Angiotension Converting Enzyme Inhibitor during Natto Fermentation (납두 발효과정 중 Angiotensin Converting Enzyme 저해물질의 생성 및 분리)

  • Cho, Young-Je;Cha, Woen-Suep;Bok, Su-Kyung;Kim, Myung-Uk;Chun, Sung-Sook;Choi, Ung-Kyu;Kim, Soon-Hee;Park, Kyung-Sook
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.29 no.4
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    • pp.737-742
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    • 2000
  • As functionality investigation of a soybean fermentation food, a angiotensin converting enzyme inhibitory peptide was separated during natto fermentation by Bacillus natto and inhibitory effect was investigated. After incubation at each 2$0^{\circ}C$, 3$0^{\circ}C$, 4$0^{\circ}C$, 5$0^{\circ}C$, 6$0^{\circ}C$ for the 0~72 hr, protein content, protease activity and angiotensin converting enzyme inhibition were determined. The protein content and protease activity were increased and reached maximum at 60 hr fermentation with 4$0^{\circ}C$ and decreased after the 60 hr fermentation during natto fermentation. The optimum condition for angiotensin converting enzyme inhibitors was appeared at fermentation for 60 hr at 4$0^{\circ}C$. Crude extract of natto was partially purified by Amicon membrane YM-3 and Sephadex G-10, G-25 gel filtration, stepwise. The inhibitory rate was increased in a concentration dependent manner, espcially the most potent activity about 74.74% at 1.0 mg peptide content. The most prominent amino acid of the peptide from natto was alanine, followed by phenylalnine, histidine.

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Effects of Heat Treatment of Chitooligosaccharide and Water-Soluble Chitosan on the Changes in Oligosaccharide Content and Anti-Rotaviral Activity (키토올리고당과 수용성 키토산의 열처리가 올리고당 함량의 변화와 항 로타바이러스성에 미치는 영향)

  • Park, B.S.;Kim, J.H.;Yu, D.H.;Yu, J.H.
    • Journal of Animal Science and Technology
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    • v.44 no.6
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    • pp.809-816
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    • 2002
  • Chitosan is the deacetylated product of chitin. Chitosan and its derivatives have many properties that make them attractive for a wide variety of health applications. This study was conducted to investigate change of oligosaccharide content and antiviral effect on rotavirus of chitooligosaccharide and water soluble chitosan after heat treatment. The quantitative analysis of oligosaccharide using colorimetry showed that oligosaccharide contents in water soluble chitosan and chitooligosaccharide were decreased from 62.67% to 60.45% and from 59.48% to 54.31%, respectively, after heating. The inhibitory effect of chitosan derivatives on MA-104 cell infected with human rotavirus(HRV) measured using AEC staining method. The inhibition level of 0.125% water-soluble chitosan against cell infection by human rotavirus was 91.98 3.09% in HRV S2 and was 89.92 1.68% in HRV Wa. But, chitooligosaccharide had not shown inhibitory effect against cell infection by HRV. It considered that most oligosaccharide of chitooligosaccharides consist of oligomer of lower polymerization degree. Heat treatment of water soluble chitosan and chitooligosaccharide did not influence their antiviral effects on rotavirus.

Estimation of Equivalent Friction Angle and Cohesion of Near-Surface Rock Mass Using the Upper-Bound Solution for Bearing Capacity of Strip Footing (줄기초 지지력 상계해를 활용한 천부 암반의 등가마찰각과 등가점착력 산정)

  • Lee, Youn-Kyou
    • Tunnel and Underground Space
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    • v.25 no.3
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    • pp.284-292
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    • 2015
  • The generalized Hoek-Brown failure criterion, the strength parameters of which are determined by using the GSI index, is an empirical nonlinear failure criterion of rock mass and has been widely employed in various rock engineering practices. Many rock engineering practitioners, however, are still familiar with the description of the strength of rock mass in terms of friction angle and cohesion. In addition, almost all rock mechanics softwares incorporate the simple linear Mohr-Coulomb function. Therefore, it is necessary to provide a tool to implement the Hoek-Brown function in the framework of the Mohr-Coulomb criterion. In this study, the use of upper-bound solution of limit analysis for bearing capacity of a strip footing resting on the ground surface is proposed for the estimation of the equivalent friction angle and cohesion of rock mass incorporating the generalized Hoek-Brown failure criterion. The upper-bound bearing capacity is expressed in terms of friction angle by use of the relationship between tangential friction angle and tangential cohesion implied in the generalized Hoek-Brown function. The friction angle minimizing the upper-bound bearing capacity is taken as the equivalent friction angle. Through the illustrative implementations of the proposed method, the influences of GSI, $m_i$ and D on the equivalent friction angle and cohesion are investigated.

Identifications of a Sprout-Rot Pathogen Pseudomonas Species SN239 and Selection Resistant Soybean Line (콩나물 부패균 Pseudomonas sp. SN239 동정과 콩나물 부패병 내병성 계통 선발)

  • Lim, Jong-Soo;Do, Kum-Sook;Lee, Dong-Sun;Kang, Sang-Gu;Suh, Sang-Gon;Park, Eui-Ho
    • Journal of Life Science
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    • v.18 no.12
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    • pp.1771-1774
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    • 2008
  • Control microbial contamination in pathogens to soy sprouts has always been highly concerned in soybean sprout industries because the soybean sprouts are consumed largely as a nutritious fresh vegetable around the world. However, pathogens in soy sprouts are little known. Here, we isolated a strain of Pseudomonas sp. SN239 that caused severer symptoms in sprouts of many soybean cultivars. In phylogenetic relationships using 16S ribosomal RNA sequences of the Pseudomonas species, the identified Pseudomonas sp. SN239 was grouped with P. putita, P. plecoglossicida, P. monteilii and P. mevalonii. Thus, the bacterial strain SN239 might be a newly identified Pseudomonas species which closely related to P. putida. Furthermore, we found that a Korean indigenous soybean (Glycine max) cultivar YNPCSS3-19 has strong resistance against the Pseudomonas sp. SN239.

Production and Characteristics of Lytic Enzyme against Streptococcus mutans Cell Wall from Alkalophilic Bacillus sp. 4830 (호알카리성 Bacillus sp. 4830이 생산하는 Streptococcus mutans 세포벽 분해효소의 분리와 특성)

  • Kim, Yun-Keun;Bai, Dong-Hoon
    • Korean Journal of Food Science and Technology
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    • v.35 no.6
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    • pp.1143-1149
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    • 2003
  • To elucidate a method of preventing dental caries, strains producing lytic enzymes were isolated and their characteristics were investigated. Among 5,00 alkalophilic strains isolated from soil, 22 strains showed lytic activity against Streptococcus mutans. Strain No. 4830, with the highest lytic activity, was selected for further study. Strain 4830 showed 94% sequence homology with the 16S rDNA sequence of Bacillus alcalophilus, but it was concluded to be different from Bacillus alcalophilus because of its biochemical characteristics. The strain was named Bacillus sp. 4830. The lytic enzyme from Bacillus sp. 4830 was purified by ethanol precipitation and CM-agarose column chromatography. The molecular weight of the lytic enzyme was determined to be 28 kDa by SDS-PAGE. The lytic enzyme was stable between pH 5.0 and pH 11 and up to $40^{\circ}C$. The optimal pH and temperature for the lytic activity was 9.0 and $50^{\circ}C$, respectively.

A Semantic Investigation of Geometric Terminology in School Mathematics (학교 수학 기하 용어의 의미론적 탐색 - 기하 용어의 역사적 변천 및 국제 비교를 중심으로 -)

  • 박경미;임재훈
    • Journal of Educational Research in Mathematics
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    • v.8 no.2
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    • pp.565-586
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    • 1998
  • Like many other school subjects, terminology is a starting point of mathematical thinking, and plays a key role in mathematics learning. Among several areas in mathematics, geometry is the area in which students usually have the difficulty of learning, and the new terms are frequently appeared. This is why we started to investigate geometric terms first. The purpose of this study is to investigate geometric terminology in school mathematics. To do this, we traced the historical transition of geometric terminology from the first revised mathematics curriculum to the 7th revised one, and compared the geometric terminology of korean, english, Japanese, and North Korean. Based on this investigation, we could find and structuralize the following four issues. The first issue is that there are two different perspectives regarding the definitions of geometric terminology: inclusion perspective and partition perspective. For example, a trapezoid is usually defined in terms of inclusion perspective in asian countries while the definition of trapezoid in western countries are mostly based on partition perspective. This is also the case of the relation of congruent figures and similar figures. The second issue is that sometimes there are discrepancies between the definitions of geometric figures and what the name of geometric figures itself implies. For instance, a isosceles trapezoid itself means the trapezoid with congruent legs, however the definition of isosceles trapezoid is the trapezoid with two congruent angles. Thus the definition of the geometric figure and what the term of the geometric figure itself implies are not consistent. We also found this kind of discrepancy in triangle. The third issue is that geometric terms which borrow the name of things are not desirable. For example, Ma-Rum-Mo(rhombus) in Korean borrows the name from plants, and Sa-Da-Ri-Gol(trapezoid) in Korean implies the figure which resembles ladder. These terms have the chance of causing students' misconception. The fourth issue is that whether we should Koreanize geometric terminology or use Chinese expression. In fact, many geometric terms are made of Chinese characters. It's very hard for students to perceive the ideas existing in terms which are made of chines characters. In this sense, it is necessary to Koreanize geometric terms. However, Koreanized terms always work. Therefore, we should find the optimal point between Chines expression and Korean expression. In conclusion, when we name geometric figures, we should consider the ideas behind geometric figures. The names of geometric figures which can reveal the key ideas related to those geometric figures are the most desirable terms.

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Screening of Immune Activation Activities in the Leaves of Dendropanax morbifera Lev. (황칠나무 잎의 면역활성증진기능 탐색)

  • Lee, Seo-Ho;Lee, Hyun-Soo;Park, Young-Sik;Hwang, Baik;Kim, Jae-Hun;Lee, Hyeon-Yong
    • Korean Journal of Medicinal Crop Science
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    • v.10 no.2
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    • pp.109-115
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    • 2002
  • The immune activation activities of ethanol, ethanol : water(1 : 1,v/v) and water extracts from Dendropanax morbifera Lev. were compared. The crude extracts showed relatively low cytotoxicity as less than 26% by using human normal liver cell(WRL-68). For example, the ethanol extract inhibited. in MCF7 and Hep3B cells in adding 1.0 mg/mL ethanol extracts. The growth of human immune T and B cells was enhanced up to $1.22{\sim}1.27$ times by adding the crude extracts. These are a trend of increasing secretion of $cytokines(IL-6,\;TNF-{\alpha})$ from human B/T cell for 6 day cultivation. It was found that the immune activation activities of the crude extracts seemed to be higher than those obtained by using other solvents.