• Title/Summary/Keyword: 탐색적연구

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Virtual Location Information based Routing Scheme in Wireless Ad-Hoc Networks (무선 애드 혹 네트워크에서 가상위치정보 기반 라우팅 기법)

  • Youn, JooSang
    • Journal of the Korea Society of Computer and Information
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    • v.18 no.2
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    • pp.77-85
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    • 2013
  • Recently, location information based routing protocol has been studied to estimate end-to-end path in wireless ad-hoc network. This protocol assumes all nodes can get heir location information via GPS devices and floods only limited area with routing message through acquired location information. Therefore, this protocol has advantage that can reduce the number of routing message than the existing IP-based routing protocols. In addition, all nodes enabling this protocol must acquire their own location information to participate in the location-based routing. However, recent because of the miniaturization of sensor node, sensor node without GPS function has been launched. Therefore in case of the sensor node that does not know location information, it is impossible to participate in the ad hoc network configuration and location information based routing. In this paper, a virtual location information based routing scheme is proposed for wireless nodes without GPS function to be able to participate in location information based routing within ad hoc network environments consisting of wireless nodes with GPS function and wireless nodes without GPS function. Therefore, the proposed protocol has the advantage that a wireless node without a GPS function is able to participate in ad hoc network configuration and the location information based routing.

An Analysis of the Conditions and Causes of Income Inequality: Focusing on the Urban Worker Households (소득불평등 실태, 원인분석 및 과제: 도시근로자 가구를 중심으로)

  • Chai, Goo-Mook
    • Korean Journal of Social Welfare
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    • v.59 no.1
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    • pp.199-221
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    • 2007
  • This study examines the conditions and causes of income inequality and seeks assignments for mitigating income inequality. An analysis of the conditions and causes of income inequality is summarized as follows. First, income inequality, which rapidly increased after the economic crisis, increased and reduced repeatedly during 1999-2004, and remained a level in 2005 as high as that of the year directly after the economic crisis. Second, an analysis of the causes of income inequality by utilizing the long-term data(1985-2004) shows that unemployment rate, nonstandard employment rate, and the rising rate of land prices positively affect income inequality. Third, an analysis of the causes of income inequality by utilizing the data before and after the economic crisis(1995-2004) demonstrates that unemployment rate, nonstandard employment rate, and the workers' income ratio between large enterprises and small enterprises positively affect income inequality. Fourth, the rising rate of land prices which significantly affects income inequality in the data of 1985-2004 does not affect income equality in the data of 1995-2004, and the workers' income ratio between large enterprises and small enterprises which does not affect income inequality in the data of 1985-2004 significantly affect income equality in the data of 1995-2004. These results suggest several implications for mitigating income inequality. First, alternative plans to reduce unemployment rate must be prepared. Second, policies to reduce nonstandard employment rate should be established. Third, programs to stabilize or lower the land prices must be deliberated. Fourth, a master-plan to support small to medium enterprises must be carried out in order to reduce the wage differentials between large enterprises and small to medium enterprises.

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Analysis of Relevance of Korean and Foreign Science Curricula and Invention (국내외 과학과 교육과정과 발명의 관련성 분석)

  • Son, Jeongwoo;Lee, Bongwoo
    • Journal of The Korean Association For Science Education
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    • v.37 no.4
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    • pp.651-658
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    • 2017
  • The purpose of this study is to analyze the invention-related content of foreign science curricula and investigate the perception of science educators about the degree of relevance between science curriculum and invention. For the analysis of foreign science curricula, we investigated the programs of 10 nations, including the US, Canada, UK, Japan, Australia, Singapore, New Zealand, France, Finland and China. To analyze the relevance between Korean science curriculum and invention, we examined common topics such as science, integrated science, and science inquiry experiment, and investigated that the elements related to invention education were included in each 'achievement standard' and 'teaching and evaluation methods'. Science educators including science teachers were asked to evaluate the degree of relevance of invention education. The results were as follows. First, science curricula in many countries contained invention-related content. Second, science educators recognized that invention education was related to science curriculum, but the systematic connection was insufficient. Third, because it is mainly limited to the results of designing and device design, they recognized that the relevance of invention education, which focuses on various processes such as problem design, inventive techniques and intellectual property, was not revealed. Therefore, it is necessary to be process-oriented when developing invention education teaching-learning methods and related materials in science education for the future.

Exploring the Improvement Plan for Science-Gifted Education through Analysis of the Performance Result of Master plan for Identifying and Nurturing of Science-Gifted Student (과학영재 발굴·육성 종합계획 성과분석을 통한 과학영재교육 발전방안 탐색)

  • Lee, Bongwoo;Son, Jeongwoo
    • Journal of The Korean Association For Science Education
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    • v.37 no.5
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    • pp.775-785
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    • 2017
  • The purpose of this study is to analyze the outcome of 'The second plan for identifying and nurturing of science-gifted student' and investigate the implications for the third plan. 'The second plan for identifying and nurturing of science-gifted student' was made for the promotion of science-gifted education from 2013 to 2017. This plan is composed of three strategies with 25 sub-projects: a systematic identification of science-gifted students with potential, an activation of creative and integrated science-gifted education and an establishment of optimized science education supporting system. We supposed six implications through the investigation of the performance analysis of each sub-project. First, the third plan should be composed of projects to be able to be supported directly. Second, the paradigm shift is needed from quantitative expansion to qualitative expansion. Third, third plan should include a special support for profoundly gifted students. Fourth, a specialization plan for science-gifted institute is required. Fifth, it is necessary to establish a camp or residential type gifted institute. Sixth, it is needed to have a quality management of science-gifted programs and MOOC (massive open online course) on science-gifted programs are needed.

Manufacturing of Watermelon Beverage Added with Natural Color Extracts (천연 색소 추출물을 첨가한 수박 음료의 제조)

  • Hwang, Young;Lee, Ki-Kwon;Jung, Gi-Tai;Ko, Bok-Rae;Choi, Dong-Chil;Choi, Joung-Sik;Eun, Jong-Bang
    • Korean Journal of Food Science and Technology
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    • v.36 no.2
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    • pp.226-232
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    • 2004
  • Dilution concentration of watermelon juice, concentrations of added sugar, citric acid, and vitamin C, sterilization temperature and time, and natural color extracts were evaluated to determine optimum conditions for watermelon beverage production. Optimum dilution concentration of watermelon juice and optimum content of soluble solid were 40% and $12^{\circ}Brix$, respectively. Addition of 0.5 and 0.3 g/L or 1.0 and 0.3 g/L citric acid and vitamin C gave optimum sensory quality. Sterilization of watermelon beverage at above $70^{\circ}C$ decreased redness. Sterilization at $60^{\circ}C$ for 10 to 30 min or at $70^{\circ}C$ for 10 min achieved best sensory quality. Addition of 20 g/L raspberries gave best sensory quality among raspberries, omija, and borage. Hot water was better than alcohol for extraction of natural color. Ratio of extracts for optimum sensory quality was 7 : 3 for extract of 20 g raspberries/L : extract of 30 g omija/L.

Cloning of Cytochrome P450 Gene involved in the Pathway of Capsidiol Biosynthesis in Red Pepper Cells (고추세포에서 Capsidiol 생합성을 유도하는 Cytochrome P450 유전자의 탐색)

  • Kwon, Soon-Tae;Kim, Jae-Sung;Jung, Do-Cheul;Jeong, Jeong-Hag;Hwang, Jae-Moon;Oh, Sei-Myoung
    • Journal of Life Science
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    • v.13 no.6
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    • pp.879-888
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    • 2003
  • In order to measure the enzyme activity of 5-epi-aristolochene hydroxylase, one of cytochrome P450 (P450) enzymes in eicitor-treated pepper cell, we used in vivo assay method and demonstrated a dramatic suppression of the activity by P450-inhibitors, ancymidol and ketocornazole. Using RT-PCR method with degenerate primer of the well conserved domains found within most P450-enzymes, and using cDNA library screening method, one distinct cDNA, being designated P450Hy01, was successfully isolated from elicitor-treated pepper cells. P450Hy01 mRNA was all induced in elicitor-treated cells whereas never induced in control cells. Moreover, levels of P450Hy01 expression were highly correlated with the levels of extracellular capsidiol production by different elicitors in cell cultures. P450Hy01 transcript was also induced by several other elicitors such as, cellulase, arachidonic acid, jasmonic acid, yeast extract as well as UV stress. P450Hy01 sequence contained high probability amino acid matches to known Plant P450 genes and ORF with a conserved FxxGxRxCxG heme-binding domain. P450Hy01 cDNA showed 98% of homology in sequence of nucleotide as well as amino acid to 5-epi-aristolochene-1, 3-hydroxylase (5EAl, 3H) which has been isolated in tobacco cells, suggesting that P450Hy01 is prominent candidate gene for P450-enzyme encoding 5EAl, 3H in pepper cell.

Phylogenetic Analysis of 680 Prokaryotes by Gene Content (유전자 보유 계통수를 이용한 원핵생물 680종의 분석)

  • Lee, Dong-Geun;Lee, Sang-Hyeon
    • Journal of Life Science
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    • v.26 no.6
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    • pp.711-720
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    • 2016
  • To determine the degree of common genes and the phylogenetic relationships among genome-sequenced 680 prokaryotes, the similarities among 4,631 clusters of orthologous groups of protein (COGs)’ presence/ absence and gene content trees were analyzed. The number of COGs was in the range of 103–2,199 (mean 1377.1) among 680 prokaryotes. Candidatus Nasuia deltocephalinicola str. NAS-ALF, an obligate symbiont with insects, showed the minimum COG, while Pseudomonas aeruginosa PAO1, an opportunistic pathogen, represented the maximum COG. The similarities between two prokaryotes were 49.30–99.78 % (mean 72.65%). Methanocaldococcus jannaschii DSM 2661 (hyperthermophilic and autotrophic, Euryarchaeota phylum) and Mesorhizobium loti MAFF303099 (mesophilic and symbiotic, alpha-Proteobacteria class) had the minimum amount of similarities. As gene content may represent the potential for an organism to adapt to each habitat, this may represent the history of prokaryotic evolution or the range of prokaryotic habitats at present on earth. COG content trees represented the following. First, two members of Chloroflexi phylum (Dehalogenimonas lykanthroporepellens BL-DC-9 and Dehalococcoides mccartyi 195) showed a greater relationship with Archaea than other Eubacteria. Second, members of the same phylum or class in the 16S rRNA gene were separated in the COG content tree. Finally, delta- and epsilon-Proteobacteria were in different lineages with other Proteobacteria classes in neighbor-joining (NJ) and maximum likelihood (ML) trees. The results of this study would be valuable to identifying the origins of organisms, functional relationships, and useful genes.

An Explorative Study on Using the Method of Natural Family Planning (자연적 가족계획방법 사용에 대한 탐색적 연구)

  • Choi, Hee-Chung;Park, Shin-Ae
    • Research in Community and Public Health Nursing
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    • v.12 no.1
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    • pp.226-238
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    • 2001
  • This study was attempted to understand experiences of the users of natural family planning(NFP) by applying Q-methodology. 37 statements were used to Q population through literature research and interviews. For the P sample. I interviewed personally 30 people who had taken a lesson in NFP for over 6 months and had been using and experiencing it autonomously for more than 2 years so far, and asked them to Q-classify the statement cards in order of the degree of approval, from the one they most approved to the one they least approved. Data were coded and input into a computer and were analyzed using QUANL PC Program. In this study, I discovered 4 types of experiences by the users of NFP and named them each according to their features: the first, a type of mutual control with morality, the second, a type of the pursuit of mutual -cooperation, the third. a type of the pursuit of conviction. and the fourth, a type of the perception of health management. The first type said that NFP was a good contraceptive way in which no drug or devices are used, that the husband's cooperation was needed, and that they became able to control sexual desire with morality. The second type perceived that continuous efforts were required to put NFP in practice, that the, husband's cooperation was essential, and that dialogues between husband and wife were also necessary to use it, and as such they regarded mutual cooperation between husband and wife as highly important. On the other hand. the third type perceived that one's conviction played a big part, that knowledge of physiological changes was useful and the ability to sense physical changes improved. and that one's willpower was important. and thus they regarded one's own willpower as most important. The fourth type reported that this method was a good way to control pregnancy and should be taught about at the beginning of sex education. and thus they were emphasizing the importance of NFP as a helpful way to manage one's health. 1. therefore, intend to provide the following suggestions based on the result of this study. 1) It is necessary to develop a program that allows NFP to be applied to sex education program. 2) It is necessary to analyze factors that affect the execution of NFP. 3) It is necessary to analyze causes of failure of those who fail to execute NFP.

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Purification and Characterization of Phospholipase D from Actinomycetes KF923. (방선균 KE923이 생산하는 Phospholipase D의 정제 및 특성)

  • 곽보연;윤석후;김창진;손동화
    • Microbiology and Biotechnology Letters
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    • v.31 no.4
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    • pp.389-394
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    • 2003
  • In order to screen microorganisms producing phopholipase D (PLD) had high transphosphatidylation activity, about 1,000 Actinomycetes strains were isolated from the 63 soil samples, collected over 6 local area in Korea. When the hydrolytic activity in the supernatant was determined, 131 strains produced PLD more than 0.3 U/ml. Among 131 culture broths tested, 23 ones had transphosphatidylation activity higher than 20% and finally one strain (Actinomycetes KF 923), which had highest hydrolytic and transphophadylation activity, was selected. Actinomycetes KF923 showed the highest hydrolytic activity (13 U/ml) and phosphatidylation activity (95%) after 48 h fermentation using the P medium (yeast extract 1%, peptone 1%, glucose 1.5%, glycerol 1%, $CaCo_3$ 0.4%, pH 7.2). PLD was purified from the culture broth of Actinomycetes KF923 and the specific activity of purified PLD was 567 U/mg. The molecular weight of PLD was about 55 kD and the optimum pH and temperature were 6.0 and $60^{\circ}C$, respectively. The stability of PLD toward pH and temperature were high around pH 8.0 and below $40^{\circ}C$. Special metal ions were not necessary to the PLD activity.

Optimization of Post-Processing for Subsequence Matching in Time-Series Databases (시계열 데이터베이스에서 서브시퀀스 매칭을 위한 후처리 과정의 최적화)

  • Kim, Sang-Uk
    • The KIPS Transactions:PartD
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    • v.9D no.4
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    • pp.555-560
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    • 2002
  • Subsequence matching, which consists of index searching and post-processing steps, is an operation that finds those subsequences whose changing patterns are similar to that of a given query sequence from a time-series database. This paper discusses optimization of post-processing for subsequence matching. The common problem occurred in post-processing of previous methods is to compare the candidate subsequence with the query sequence for discarding false alarms whenever each candidate subsequence appears during index searching. This makes a sequence containing candidate subsequences to be accessed multiple times from disk, and also have a candidate subsequence to be compared with the query sequence multiple times. These redundancies cause the performance of subsequence matching to degrade seriously. In this paper, we propose a new optimal method for resolving the problem. The proposed method stores ail the candidate subsequences returned by index searching into a binary search tree, and performs post-processing in a batch fashion after finishing the index searching. By this method, we are able to completely eliminate the redundancies mentioned above. For verifying the performance improvement effect of the proposed method, we perform extensive experiments using a real-life stock data set. The results reveal that the proposed method achieves 55 times to 156 times speedup over the previous methods.