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A Review of Multivariate Analysis Studies Applied for Plant Morphology in Korea (국내 식물 형태 연구에 사용된 다변량분석 논문에 대한 재고)

  • Chang, Kae Sun;Oh, Hana;Kim, Hui;Lee, Heung Soo;Chang, Chin-Sung
    • Journal of Korean Society of Forest Science
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    • v.98 no.3
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    • pp.215-224
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    • 2009
  • A review was given of the role of traditional morphometrics in plant morphological studies using 54 published studies in three major journals and others in Korea, such as Journal of Korean Forestry Society, Korean Journal of Plant Taxonomy, Korean Journal of Breeding, Korean Journal of Apiculture, Journal of Life Science, and Korean Journal of Plant Resources from 1997 to 2008. The two most commonly used techniques of data analysis, cluster analysis (CA) and principal components analysis (PCA) with other statistical tests were discussed. The common problem of PCA is the underlying assumptions of methods, like random sampling and multivariate normal distribution of data. The procedure was intended mainly for continuous data and was not efficient for data which were not well summarized by variances or covariances. Likewise CA was most appropriate for categorical rather than continuous data. Also, the CA produced clusters whether or not natural groupings existed, and the results depended on both the similarity measure chosen and the algorithm used for clustering. An additional problems of the PCA and the CA arised with both qualitative and quantitative data with a limited number of variables and/or too few numbers of samples. Some of these problems may be avoided if a certain number of variables (more than 20 at least) and sufficient samples (40-50 at least) are considered for morphometric analyses, but we do not think that the methods are all mighty tools for data analysts. Instead, we do believe that reasonable applications combined with focus on objectives and limitations of each procedure would be a step forward.

Analysis of Factors Influencing Entrepreneurial Performance at the University Level for Becoming Entrepreneurial Universities (기업가형 대학(Entrepreneurial University)을 위한 대학의 창업 성과 영향요인 분석)

  • Lim, Hanryeo;Hon, Sungpyo
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.15 no.2
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    • pp.19-32
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    • 2020
  • The purpose of this study was to investigate the influence factors of the university level centering on the entrepreneurial performance of the university students and full-time faculties in the situation of increasing interest in entrepreneurial university. In order to achieve the purpose of the study, a panel data was established from 2015 to 2018 on the basis of the university notification data. The panel data included universities with data on the number of university students and full-time faculty founders for at least two years. Through this, four year data from 154 universities were used for analysis. As an analysis method, frequency analysis and descriptive statistics were conducted to understand the characteristics of the university. Since then, panel negative binomial regression analysis has been conducted in consideration of the longitudinal features and distribution of the data. Also, based on the Hausman test results, the results were interpreted based on random effect model. The results of this study are as follows. First, as a result of the analysis of the entrepreneurial performance and the change trend of the domestic university from 2015 to 2018, the entrepreneurial performance of the university has been steadily increasing in the last four years, and the increase in the number of university student entrepreneurs was relatively higher than the full-time faculties. Second, economic and educational approaches need to be combined to promote university students' start-ups. The university factors that promote the start-up of university students were found to be scholarships, start-up grants, startup lectures, and startup clubs. Third, the openness and regional characteristics of the univeristy can promote the establishment of university students. Fourth, the establishment of a research environment and support for start-ups for full-time faculty members can enhance their start-up performance. The university factors that promote the start-up of full-time faculty were research funds and staffes who support start-up. The conclusions drawn from these findings are as follows. First, overall efforts are needed to develop into an entrepreneurial university. Second, in order to change into an entrepreneurial university, direct support for entrepreneurship is needed. Third, as an entrepreneurial university, it is necessary to find a way to bridge the gap by university according to region and size. Fourth, it is necessary to reinforce the support for linking the research results of universities to start-ups. Fifth, it is necessary to improve the atmosphere for full-time faculty members to be entrepreneur.

The Health Status of Rural Farming Women (농촌여성(農村女性)의 건강실태(健康實態)에 관한 연구(硏究))

  • Park, Jung-Eun
    • Journal of agricultural medicine and community health
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    • v.15 no.2
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    • pp.97-106
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    • 1990
  • 1. Background Women's health and their involvement in health care are essential to health for everyone. If they are ignorant, malnourished or over-worked, the health &-their families as well as their own health will suffer. Women's health depends on broad considerations beyond medicine. Among other things, it depends upon their work in farming. their subordination to their families, their accepted roles, and poor hygiene with poorly equipped housing and environmental sanitation. 2. Objectives and Contents a. The health status of rural women : physical and mental complaints, experience of pesticides intoxication, Farmer's syndrome, experiences of reproductive health problems. b. participation in and attitudes towards housework and farming c. accessibility of medical care d. status of maternal health : fertility, family planning practice. induced abortion, and maternal care 3. Research method A nationwide field survey, based on stratified random sampling, was conducted during July, 1986. Revised Cornell Medical index(68 out of 195 items). Kawagai's Farmers Syndrome Scale, and self-developed structured questionnaires were used to rural farming wives(n=2.028). aged between 26-55. 4. Characteristics of the respondents mean age : 40.2 marital status : 90.8% married mean no. of household : 4.9 average years of education : 4.7 yrs. average income of household : \235,000 average years of residence in rural area : 36.4 yrs average Working hours(household and farming) : 11 hrs. 23 min 5. Health Status of rural women a. The average number of physical and mental symptoms were 12.4, 4.7, and the rate of complaints were 22.1%, 38.8% each. revealing complaints of mental symptomes higher than physical ones. b. 65.4% of rural women complained of more than 4 symptoms out of 9, indicating farmer's syndrome. 11.9 % experienced pesticide overdue syndrome c. 57.6% of respondents experienced women-specific health problems. d. Age and education of respondents were the variables which affect on the level of their health 6. Utilization of medical services a. The number of symptoms and complaints of respondents were dependent on the distance to where the health-care service is given b. Drug store was the most commonly utilized due to low price and the distance to reach. while nurse practitioners were well utilized when there were nurse practitioner's office in their villages. c. Rural women were internalized their subordination to husbands and children, revealing they are positive(93%) in health-care demand for-them but negative(30%) for themselves d. 33.0% of respondents were habitual drug users, 4.5% were smokers and 32.3% were alcohol drinkers. and 86.3% experienced induced-abortion. But most of them(77.6%) knew that those had negative effects on health. 7. Maternal Health Care a. Practice rate of contraception was 48.1% : female users were 90.9% in permanent and 89.6% in temporary contraception b. Induced abortions were taken mostly at hospital(86.3%), while health centers(4.7%), midwiferies(4.3%). and others(4.5%) including drug stores were listed a few. The repeated numbers of induced abortion seemed affected on the increasing numbers of symptoms and complaints. c. The first pre-natal check-up during first trimester was 41.8%, safe delivery rate was 15.6%, post-natal check-up during two months after delivery. Rural women had no enough rest after delivery revealing average days of rest from home work and farming 8.3 and 17.2. d. 86.6% practised breast feeding, showing younger and more educated mothers depending on artificial milk 8. Recommendations a. To lessen the multiple role over burden housing and sanitary conditions should be improved, and are needed farming machiner es for women and training on the use of them b. Health education should begin at primary school including health behavior and living environment. c. Women should be encouraged to become policy-makers as well as administrators in the field of women specific health affairs. d. Women's health indicators should be developed and women's health surveillance system too.

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The Study on the Reduction of Patient Surface Dose Through the use of Copper Filter in a Digital Chest Radiography (디지털 흉부 촬영에서 구리필터사용에 따른 환자 표면선량 감소효과에 관한 연구)

  • Shin, Soo-In;Kim, Chong-Yeal;Kim, Sung-Chul
    • Journal of radiological science and technology
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    • v.31 no.3
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    • pp.223-228
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    • 2008
  • The most critical point in the medical use of radiation is to minimize the patient's entrance dose while maintaining the diagnostic function. Low-energy photons (long wave X-ray) among diagnostic X-rays are unnecessary because they are mostly absorbed and contribute the increase of patient's entrance dose. The most effective method to eliminate the low-energy photons is to use the filtering plate. The experiments were performed by observing the image quality. The skin entrance dose was 0.3 mmCu (copper) filter. A total of 80 images were prepared as two sets of 40 cuts. In the first set (of 40 cuts), 20 cuts were prepared for the non-filter set and another 20 cuts for the Cu filter of signal + noise image set. In the second set of 40 cuts, 20 cuts were prepared for the non-filter set and another 20 cuts for the Cu filter of non-signal image (noisy image) with random location of diameter 4 mm and 3 mm thickness of acryl disc for ROC signal at the chest phantom. P(S/s) and P(S/n) were calculated and the ROC curve was described in terms of sensitivity and specificity. Accuracy were evaluated after reading by five radiologists. The number of optically observable lesions was counted through ANSI chest phantom and contrast-detail phantom by recommendation of AAPM when non-filter or Cu filter was used, and the skin entrance dose was also measured for both conditions. As the result of the study, when the Cu filter was applied, favorable outcomes were observed on, the ROC Curve was located on the upper left area, sensitivity, accuracy and the number of CD phantom lesions were reasonable. Furthermore, if skin entrance dose was reduced, the use of additional filtration may be required to be considered in many other cases.

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The Phenomenological Comparison between Results from Single-hole and Cross-hole Hydraulic Test (균열암반 매질 내 단공 및 공간 간섭 시험에 대한 현상적 비교)

  • Kim, Tae-Hee;Kim, Kue-Young;Oh, Jun-Ho;Hwang, Se-Ho
    • Journal of Soil and Groundwater Environment
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    • v.12 no.5
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    • pp.39-53
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    • 2007
  • Generally, fractured medium can be described with some key parameters, such as hydraulic conductivities or random field of hydraulic conductivities (continuum model), spatial and statistical distribution of permeable fractures (discrete fracture network model). Investigating the practical applicability of the well-known conceptual models for the description of groundwater flow in fractured media, various types of hydraulic tests were applied to studies on the highly fractured media in Geumsan, Korea. Results from single-hole packer test show that the horizontal hydraulic conductivities in the permeable media are between $7.67{\times}10^{-10}{\sim}3.16{\times}10^{-6}$ m/sec, with $7.70{\times}10^{-7}$ m/sec arithmetic mean and $2.16{\times}10^{-7}$ m/sec geometric mean. Total number of test interval is 110 at 8 holes. The number of completely impermeable interval is 9, and the low permeable interval - below $1.0{\times}10^{-8}$ m/sec is 14. In other words, most of test intervals are permeable. The vertical distribution of hydraulic conductivities shows apparently the good correlation with the results of flowmeter test. But the results from the cross-hole test show some different features. The results from the cross-hole test are highly related to the connectivity and/or the binary properties of fractured media; permeable and impermeable. From the viewpoint of the connection, the application of the general stochastic approach with a single continuum model may not be appropriate even in the moderately or highly permeable fractured medium. Then, further studies on the investigation method and the analysis procedures should be required for the reasonable and practical design of the conceptual model, with which the binary properties, including permeable/impermeable features, can be described.

Characteristics and breeding of a new cultivar Pleurotus eryngii, Song-A (큰느타리버섯 신품종 '송아'의 육성 및 그 특성)

  • Shin, Pyung-Gyun;Park, Yun-Jung;Yoo, Young-Bok;Kong, Won-Sik;Jang, Kab-Yeul;Cheong, Jong-Cheon;Oh, Se-Jong;Lee, Keum-Hee
    • Journal of Mushroom
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    • v.9 no.2
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    • pp.59-62
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    • 2011
  • To develop a new cultivar of King oyster mushroom(Pleurotus eryngii), G09-21 as parental strain was selected by the method of Di-mon crossing between monokaryotic strains derived from ASI 2824(Keunneutari No.2) and dikaryotic strain ASI 2887(Aeryni 3). The Pe21-51($G09-21-10{\times}2844-11$) was shown the best cultural characteristics, selected to be a new cultivar and named as 'Song-A'. The 'Song-A' was formed incompatibility line distinctly in the confrontation growth of parental strains Keunneutari No.2, Aeryni 3 and ASI 2844. The optimum temperature for mycelial growth, fruiting body development and pH arrange were $25{\sim}30^{\circ}C$, $14{\sim}16^{\circ}C$ and pH5~8, respectively. Fruiting body production per bottle was about $94.7{\pm}29.5$ g which is almost 106% quantity compared to that of other cultuvar Keunneutari No.2. And also the stip is thick and long but the number of available stipe is few. Analysis of the genetic characteristics of the new cultivar 'Song-A' showed a different DNA profile as that of the control strains, Keunneutari No.2, Aeryni 3 and ASI 2844, when RAPD(Random Amplified Polymorphic DNA) primers URP4 and 7 were used. This new cultivar 'Song-A' of Pleurotus eryngii is characterized by a small number of primordia formation and the stip is thick and long. Therefore, we expect that this new strain will save of labor and cost by without culling work.

The Variation of Nutural Population of Pinus densiflora S. et Z. in Korea -Change of variance due to number of family as sample size to affirm the population and family variations- (소나무 천연집단(天然集團)의 변이(變異)에 관(關)한 연구(硏究)(IV) -집단간(集團間) 및 가계간분산(家系間分散) 추정(推定)에 영향하는 가계수(家系數)에 대하여-)

  • Yim, Kyong Bin;Kwon, Ki Won;Lee, Kyong Jae
    • Journal of Korean Society of Forest Science
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    • v.35 no.1
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    • pp.39-46
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    • 1977
  • In the analysis of variance between population and between individual trees (families), the fluctuation of values of variances due to sample size, (number of family) was analysed by two different designs, i.e. 2-level nested design with equal sample size and randomized complete block design. The variables were seedling heights and root calipers of 1-0 and 1-1 seedlings of Pinus densiflora S. et Z. The details of three natural stands and their progeny characters were presented in previous reports. 1. In nested design analysis. increase of sample size resulted the decrease of F-values among families in general, however, the F-values among populations showen the increasing tendency. The smaller the sample size, the larger the F-values fluctuation was resulted in general. At the point of beyond sample size 10, however, the fluctuation become to be stabilized. The F-value fluctuation seemed to be more in the case of analysis with random sampling method than with sequentially accumulated sampling method. And also such a tendency was more obvious in smaller sample size than in large one. 2. In R.C.B.D. analysis, the sample size to affirm the family variation was smaller than that for population variations.

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Physical Characteristics and Microsatellite Polymorphisms in Miryang Native Dogs (밀양지방 토종개의 형태학적 특징 및 유전적 다양성 연구)

  • Cho, Byung-Wook;Cho, Gil-Jae
    • Journal of Life Science
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    • v.16 no.4
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    • pp.626-631
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    • 2006
  • This study was carried out to investigate the physical characteristics (height, body lenght, chest depth, head type, ear type, body color, eye type and tail type) and genetic diversity using 15 microsatellite DNA markers (PEZ 1, 5, 8, 10, 11, 12, 13, 15, 16, 17, 20, 21, FHC 2010, FHC 2054 and FHC 2079) in 44 random Miryang native dogs(6 months${\sim}$12 years old). The height, body lenght, and chest depth of Miryang native dogs were 43-55 cm(mean 49.5 cm), 45-60 cm(mean 54.3 cm), and 50-64 cm(mean 57.9 cm), respectively. Miryang native dog was medium sized. The head and eye type were reverse-triangle(100%), triangle (90.9%) and newborn moon(9.1%), respectively. Most of body color had white coat color(93.2%), light pink tongue color(100%), light black anal color(90,9%) and pink claw color(100%). The ear type showed erect ear(100%), and half-curled(56.8%), upward(34.1%), curled(9.1%) in tail type, respectively. Number of alleles observed at a single locus ranged from 2 (PEZ 21 and FHC 2010) to 14 (PEZ 13), with average number of alleles per locus of 6.13. The expected heterozygosities of 15 microsatellite loci were estimated based on gene frequencies. The highest expected heterozygosity, 0.863 was estimated in PEZ 13 locus and the lowest, 0.455 in PEZ 21 and FHC 2010 locus. And the mean expected heterozygosity of 15 microsatellite markers was calculated as 0.635. Polymorphic information content (PIC) values were ranged from 0.348 (PEZ 21 and FHC 2010) to 0.837 (PEZ 13), and the mean PIC value was calculated as 0.570. Of the 15 markers, PEZ 10, PEZ 13, PEZ 17 and FHC 2054 loci have relatively high PIC value (> 0.7) in Miryang native dog. In order to determine the efficieney of parentage control, exclusion probabilities (PE) were calculated for each allele. The highest PE 1 and PE 2 in PEZ 13 locus was caculated to 0.548 and 0.710, respectively. And the total exclusion power in PE 1 and PE 2 was calculated to 0.9895 and 0.9996, respectively. These results can give basic information for perservation and research in Miryang native dog, and phylogenetic relationships of the Korean native dog and Asian dog breeds.

Analysis for the Major Traits and Genetic Similarity of Native Ginseng (Panax Ginseng C.A. Meyer) Collections in Korea. (인삼(Panax ginsneg C.A. Meyer) 수집종의 주요 특성 및 유연관계 분석)

  • Rhim, Soon-Young;Sohn, Jae-Keun;Ryu, Tae-Seok;Kwon, Tae-Ryong;Choi, Jin-Kook;Choi, Hong-Jib
    • Korean Journal of Breeding Science
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    • v.42 no.5
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    • pp.488-494
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    • 2010
  • In this study, the major agronomic traits were investigated and RAPD technique was applied for the analysis of the genetic relations between the native ginsengs collected from Poonggi and Geumsan provinces in Korea. The main morphological traits were measured for a total of 54 collections of native ginseng from two areas based on UPOV standard. A total of 58 collections consisting of twenty-one native ginsengs collections from Poonggi area, twenty-nine collections from Geumsan area and four varieties of P. quinquefolium, P. japonicum, Chunpoong and Hwangsuk as controls were analyzed and clustered by RAPD. The results indicated that 01-9, 01-35 and 01-44 collections from Poonggi area were grouped into Geumsan area, while 332001, 332002 and 332003 collections from Geumsan area were grouped into Poonggi area. On comparison to the similarity of Poonggi collections (73-95%), the Geumsan collections showed 65-86% similarity in the population. Thus, the cluster should be applied according to the number of stem, number of leaves per stem and leaflet shape on the regionally native ginseng collections. The fourteen primers such as OPA02, OPA07, OPC08, OPD11, OPD20 and so on, will be used to select the native ginseng in the future studies.

Positron Annihilation Spectroscopy of Active Galactic Nuclei

  • Doikov, Dmytry N.;Yushchenko, Alexander V.;Jeong, Yeuncheol
    • Journal of Astronomy and Space Sciences
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    • v.36 no.1
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    • pp.21-33
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    • 2019
  • This paper focuses on the interpretation of radiation fluxes from active galactic nuclei. The advantage of positron annihilation spectroscopy over other methods of spectral diagnostics of active galactic nuclei (therefore AGN) is demonstrated. A relationship between regular and random components in both bolometric and spectral composition of fluxes of quanta and particles generated in AGN is found. We consider their diffuse component separately and also detect radiative feedback after the passage of high-velocity cosmic rays and hard quanta through gas-and-dust aggregates surrounding massive black holes in AGN. The motion of relativistic positrons and electrons in such complex systems produces secondary radiation throughout the whole investigated region of active galactic nuclei in form of cylinder with radius R= 400-1000 pc and height H=200-400 pc, thus causing their visible luminescence across all spectral bands. We obtain radiation and electron energy distribution functions depending on the spatial distribution of the investigated bulk of matter in AGN. Radiation luminescence of the non-central part of AGN is a response to the effects of particles and quanta falling from its center created by atoms, molecules and dust of its diffuse component. The cross-sections for the single-photon annihilation of positrons of different energies with atoms in these active galactic nuclei are determined. For the first time we use the data on the change in chemical composition due to spallation reactions induced by high-energy particles. We establish or define more accurately how the energies of the incident positron, emitted ${\gamma}-quantum$ and recoiling nucleus correlate with the atomic number and weight of the target nucleus. For light elements, we provide detailed tables of all indicated parameters. A new criterion is proposed, based on the use of the ratio of the fluxes of ${\gamma}-quanta$ formed in one- and two-photon annihilation of positrons in a diffuse medium. It is concluded that, as is the case in young supernova remnants, the two-photon annihilation tends to occur in solid-state grains as a result of active loss of kinetic energy of positrons due to ionisation down to thermal energy of free electrons. The single-photon annihilation of positrons manifests itself in the gas component of active galactic nuclei. Such annihilation occurs as interaction between positrons and K-shell electrons; hence, it is suitable for identification of the chemical state of substances comprising the gas component of the investigated media. Specific physical media producing high fluxes of positrons are discussed; it allowed a significant reduction in the number of reaction channels generating positrons. We estimate the brightness distribution in the ${\gamma}-ray$ spectra of the gas-and-dust media through which positron fluxes travel with the energy range similar to that recorded by the Payload for Antimatter Matter Exploration and Light-nuclei Astrophysics (PAMELA) research module. Based on the results of our calculations, we analyse the reasons for such a high power of positrons to penetrate through gas-and-dust aggregates. The energy loss of positrons by ionisation is compared to the production of secondary positrons by high-energy cosmic rays in order to determine the depth of their penetration into gas-and-dust aggregations clustered in active galactic nuclei. The relationship between the energy of ${\gamma}-quanta$ emitted upon the single-photon annihilation and the energy of incident electrons is established. The obtained cross sections for positron interactions with bound electrons of the diffuse component of the non-central, peripheral AGN regions allowed us to obtain new spectroscopic characteristics of the atoms involved in single-photon annihilation.