• 제목/요약/키워드: Single parent

검색결과 369건 처리시간 0.03초

식물육종에 있어서 비환원 ( 2n ) 배우자의 중요성 (Significance of Unreduced ( 2n ) Gametes in Plant Breeding)

  • Rim, Yong-Woo
    • 한국초지조사료학회지
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    • 제17권1호
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    • pp.1-10
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    • 1997
  • Unreduced (2n) gametes are meiotic products (pollen or egg) having a sporophytic (somatic) chromosome number, resulting from abnormalities during either microsporogenesis or megasporogenesis. They occur naturally at a low frequency in many plant species. Unreduced (2n) gametes in plants can be identified for four possible ways as follow i) pollen size and/or shape differences between haploid (n) and diploid (2n) pollen, ii) ploidy analysis (chromosome number) of progeny or meiotic analysis (presence of dyads andlor triads at the microspore stage), iii) progeny performance and fertility and iv) dosage of isozyme and DNA markers. Unreduced (2n) gametes can be an effective breeding tool in synthesizing new cultivars, providing a unique method to maximizing heterozygosity, i.e., transferring a large proportion of the non-additive genetic effects (intra- and inter- locus interactions) h m parent to offspring and can also be used to overcome infertility of interploidy crosses. Sexual polyploidization through 2n gametes has been a major route to the formation of naturally occurring polyploids. The three mechanisms of 2n pollen formation in potato have been discovered as follow: i) parallel spindles (ps) or tripolar spindles (ts), ii) premature cytokinesis (pc-I, pc-2) and iii) synaptic mutants (sy-2, sy-3, sy-4). Genetic analysis indicated that the mechanisms of 2n gamete formation were controlled by single recessive gene in potato, alfalfa, red clover, etc., and by two recessive genes in wheat. The use of 2n gametes which can efficiently transfer germplasm fiom wild relatives to cultivated species, especially fiom diploid to tetraploid could make a contribution to the improvement of germplasm base in breeding programs.

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흰가루병 저항성 동양종 호박 품종 육성 (Breeding for Powdery Mildew Resistant Varieties in Cucurbita moschata)

  • 조명철;엄영현;김대현;허윤찬;김정수;박효근
    • 식물병연구
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    • 제11권2호
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    • pp.106-114
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    • 2005
  • To breed powdery mildew resistant varieties, 104 accessions of Cucurbita spp. germplasm were evaluated. Powdery mildew resistance and horticultural characteristics of the accessions were investigated in the field conditions. C. martinezii was selected for high resistance to powdery mildew in the field. The growth of powdery mildew pathogen and response of leaf surface tissue to the pathogen were observed after artificial inoculation to resistant C martinezii and susceptible C. moschata cv. 'Wonye No.402'. Mycelium growth was very clearly different between resistant C. martinezii and susceptible C moschata cv. 'Wonye No. 402' at 5 days after inoculation at the adult stage. Interspecific hybridization was attempted to transfer powdery mildew resistance gene(s) from C. martinezii to C. moschata. A single dominant gene action was postulated as deter mining powdery mildew resistance at the seedling stage. But for the effective selection of powdery mildew resistant individuals, it was established that adult plant resistance should be confirmed in the field conditions after the seedling test. Through the seedling and field tests, C. moschata lines resistant to powdery mildew and superior to horticultural characteristics, were selected after 2 backcrossing and 3 selfing generations. The fruit characteristics of newly developed lines were similar to those of the recurrent parent, 'Jaechenjarae'.

Exact calculation of natural frequencies of repetitive structures

  • Williams, F.W.;Kennedy, D.;Wu, Gaofeng;Zhou, Jianqing
    • Structural Engineering and Mechanics
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    • 제4권5호
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    • pp.553-568
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    • 1996
  • Finite element stiffness matrix methods are presented for finding natural frequencies (or buckling loads) and modes of repetitive structures. The usual approximate finite element formulations are included, but more relevantly they also permit the use of 'exact finite elements', which account for distributed mass exactly by solving appropriate differential equations. A transcendental eigenvalue problem results, for which all the natural frequencies are found with certainty. The calculations are performed for a single repeating portion of a rotationally or linearly (in one, two or three directions) repetitive structure. The emphasis is on rotational periodicity, for which principal advantages include: any repeating portions can be connected together, not just adjacent ones; nodes can lie on, and members along, the axis of rotational periodicity; complex arithmetic is used for brevity of presentation and speed of computation; two types of rotationally periodic substructures can be used in a multi-level manner; multi-level non-periodic substructuring is permitted within the repeating portions of parent rotationally periodic structures or substructures and; all the substructuring is exact, i.e., the same answers are obtained whether or not substructuring is used. Numerical results are given for a rotationally periodic structure by using exact finite elements and two levels of rotationally periodic substructures. The solution time is about 500 times faster than if none of the rotational periodicity had been used. The solution time would have been about ten times faster still if the software used had included all the substructuring features presented.

불타(佛陀)의 재가아동관(在家兒童觀) (Buddha's View on Children in the Family)

  • 백경임
    • 아동학회지
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    • 제2권
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    • pp.55-66
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    • 1981
  • Research on children should be perferably made in reference with the past thinking if it is to be affirmed by the present and to predict the future. In this respect, Buddhism, which is one of the major original thinkings in the Orient as well as the most influential religion upon Koreans daily lives and attitudes, deserves to be researched in the light of education of children. In this thesis, I have made a trial to delve into the original Buddhistic scriptures to find out Buddha's outlook on home children and arrived at the following conclusions: 1. Concerning human development stages, Buddha regarded the starting point of human life from fertilization instead of birth, even at that ancient time, and the fetal life was devided into 4, 5, or 8 stages. 2. In spite of the numerous scriptures by Buddha, very little is written about children, and even these teaching did not regard the child as an independent entity. In addition, since Buddha was a person of superior enlightenment, he did not regard the age of human beings as of great importance. 3. On the relationship between parents and children, Buddha warned the extra ordinary attachment of parents toward children, because such attachment would be an obstacle in the search of truth. This idea was originated from his thought that the relationship between parents and children was not a single fixed one but of unlimited variation through numerous life times of reincarnation. This idea gives some illumination upon the problems of today's education where parent's exclusive attachment to their children and over-protection are hindrance for successful education. 4. Buddha put emphasis on parents' social duty, by which he meant that parents should care and accept not only their biological children but all children and all living things as if they were their own children. 5. Regardeding the children's role to their parents, Buddha taught that children should respect and support their parents under any condition. Buddha also emphasized that true filial piety was to help parents to improve their religious status by helping them attain the truth, morality, and wisdom. It is my intention to investigate Buddha's View tin children of entering pristhood.

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초등학생의 식생태에 관한 지역별 비교 (Comparison of The Food and Nutrition Ecology of Elementary School Children by Regions)

  • 승정자;성미경;최미경;김미현;서유리;박은숙;백정자;서정숙;모수미
    • 대한지역사회영양학회지
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    • 제8권5호
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    • pp.642-651
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    • 2003
  • This study was performed using mealtime atmosphere to characterize the food ecology of Korean children residing in different regions of Korea. A total of 705 elementary school students, 347 girls and 358 boys, were divided into three groups according to the areas where they lived, which included Seoul (n=230), provincial cities (n=273) and rural areas (n=202). The subjects were asked to fill out questionnaires which were categorized to determine various factors related to food ecology, life styles, and health related symptoms. The average age of the study subjects was 11.5 years. The results showed that the average height (p<0.01), weight (p<0.01) and body mass index (BMIs) (p< 0.01) of the rural group were significantly lower than those of the Seoul and provincial city groups. A significantly higher proportion (10.4%) of the rural group was from disfunctional families, including single parent families, than those of the Seoul (1.7%) or provincial city (4.4%) groups. However, a larger number of children from Seoul ate alone, did not enjoy their meals, and hardly talked to each other during breakfast time, compared to those from the provincial city or rural areas. Also, the proportion (33.0%) of ‘good’ in balance of meal was the lowest (33.0%) in Seoul of the three areas (p<0.01). Most of the children answered that they liked having breakfast and dinner with the whole family. In conclusion, the food ecology of elementary children differed according to the regions in which they resided. Although children from Seoul had higher BMIs, their nutritional intake was not satisfactory, and their undesirable food ecology could be a contributing factor.

안락사에 대한 간호사의 의식 (A Study on Attitude of Nurses toward Euthanasia)

  • 홍명선
    • 한국보건간호학회지
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    • 제14권2호
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    • pp.446-463
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    • 2000
  • The purpose of this study is to identify the recent attitude of nurses toward euthanasia. and to provide necessary basic information for on-the-job-training and student education. The subject of this study are 521 nurses working in the hospital attached to university in Seoul. to whom I distributed questionnaires which were made on the basis of the instrument of Tordella & Neutens. from 21. July. 2000 to 27. July. 2000. The collected data were statistically examined through SPSS program and were analysed through Frequency. Means. Factor Analysis. T-test. and ANOVA. The study results are as follows: 1. General characteristics of nurses are in age of average 26.9. in education of junior college graduate $83.7\%$. in both parent alive $85.2\%$. in marital status of single $77.5\%$. in religion of christianity $34.8\%$ against non-religion 38.3%. The term of employment is average 52.7 months and are in various post. The experience of family dying $46.3\%$ and of terminal care $56.8\%\;and\;82.5\%$ are information oriented to euthanasia. 2. The attitude toward euthanasia reveals 3.40 score in average. and is significant in relation to religion among general characteristics (p<.000). 3. Passive euthanasia reveals 2.48 score in average with significance in religion(p<.000), and duty post (p<.046). Natural euthanasia is 4.09 score which is in most characteristics positive direction with significance in information oriented group. Indirect euthanasia reveals 2.98 score and are significant in various group of age (p<.004). both parents alive (p<.005), marital status (p<.000). term of employment (p<.022), duty post (p<.005), and family dying(p<.028). Family commitment is 3.51 score with significance in both parents alive (p<.023) and term of employment (p<.020). Clear definition of euthanasia and analysis of its effects need to be studied in order to improve proper courses of nursing patients with terminal illness.

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로지스틱회귀모형을 활용한 아동학대 가족의 연구 (Study of child abuse families using logistic regression models)

  • 민대기;최미경
    • Journal of the Korean Data and Information Science Society
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    • 제27권5호
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    • pp.1327-1336
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    • 2016
  • 우리나라에서 발생하는 아동학대의 대부분은 가정 내에서 부모에 의해 발생하며 해가 갈수록 증가하는 추세이다. 성장기에 있는 아동을 대상으로 한 학대는 아동의 발달전반에 피해를 주며, 그 영향이 장기화되어 청소년기 부적응, 성인기 범죄로까지 이어지기 쉬우므로, 사회의 각별한 주의가 요구된다. 급변하는 사회 환경 속에서 맞벌이, 한 부모 가족 등 다양한 가족형태가 등장했으며, 취약한 경제구조속에서 가장들의 고용형태의 불안정은 가족들을 더욱 불안하게 만들고 있다. 이러한 환경 속에서 힘이 없는 아동은 무방비 상태로 부모로부터 신체적, 정신적 학대를 경험할 위험에 놓인다. 어려운 사회 경제적 환경 속에서 어떤 형태의 가정에서 아동학대가 많이 발생하는지에 대하여 회귀모형을 통하여 연구하였다.

무선 센서 네트워크를 위한 대규모 장애 적응적 라우팅 프로토콜 (Large Scale Failure Adaptive Routing Protocol for Wireless Sensor Networks)

  • 이좌형;선주호;정인범
    • 정보처리학회논문지A
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    • 제16A권1호
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    • pp.17-26
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    • 2009
  • 무선센서네트워크는 위험 지역에서의 데이터 수집 용도로 최근 각광받고 있는 기술이다. 하지만 위험한 지역에서는 다수 노드들에서 동시 다발적인 장애발생 위험이 크기 때문에 대규모의 장애를 빠르게 복구시키기 위한 자가 복구 능력을 높여야 한다. 기존의 라우팅 프로토콜들은 하나의 노드에서 발생한 장애는 빠르게 복구하지만 다수의 노드들에서 장애 발생시 이에 효과적으로 대처하지 못한다. 이에 본 논문에서는 대규모 장애 발생시 이를 빠르게 복구하기 위한LSFA(Large Scale Failure Adaptive Routing Protocol)을 제안한다. LSFA는 다수의 노드들에 장애가 발생하여 데이터 전송이 이루어지지 못하는 환경에서 장애를 빠르게 감지하고 라우팅 주기를 적응적으로 조절하여 빠른 시간에 네트워크를 복구한다. LSFA는 패킷손실 정도를 장애발생 판단의 기준으로 사용하며 장애를 감지하면 라우팅 주기를 짧게 하여 장애가 발생한 사실이 네트워크에 빠르게 퍼지도록 한다. 베이스스테이션으로의 경로를 유지하고 있는 노드가 주위에 장애가 발생한 사실을 감지하면 자신의 라우팅 정보를 빠르게 전파시켜 장애 복구가 빠르게 이루어지도록 한다. 실험을 통하여 LSFA가 다른 프로토콜들에 비해 적은 패킷을 사용하면서도 장애를 빠르게 복구함을 보인다.

맞벌이 가정 자녀를 위한 기초 생활습관 형성 및 기초 영어회화 교육 로봇 설계 및 구현 - 만 5세 이상 아동을 중심으로 (Design and Implementation of The Formation of Basic living habits and Basic English Conversation Education Robot for Children in Dual Income Households - focused children over five)

  • 김경민;이강희
    • 문화기술의 융합
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    • 제6권1호
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    • pp.507-513
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    • 2020
  • 본 논문에서 우리는 단일보드 컴퓨터인 라즈베리 파이3 기반의 오픈 플랫폼 로봇 Q.bo one을 이용하여 맞벌이 가정의 아이들의 생활 습관과 영어회화 교육을 케어해줄 로봇을 설계 및 구현하고자 한다. 첫 번째 생활습관 형성 기능은 성장기 아이들에게 가장 중요한 생활습관인 손씻기, 규칙적인 식사, 양치질, 숙제, 규칙적인 수면 총 5가지를 선정하여 부모가 부재중일 때에도 로봇으로 부모 목소리를 출력함으로서 아이에게 생활습관이 자리 잡을 수 있도록 도와준다. 알림을 듣고 실행에 옮긴 아이의 모습을 촬영하여 부모가 확인하고 피드백을 할 수 있게 한다. 두 번째 기초회화 교육 기능은 구글의 DialogFlow를 사용하여 로봇과 아이가 간단한 영어 회화를 통해 영어를 자연스럽게 익힐 수 있도록 도와준다. 이 두 가지 기능의 로봇을 통해 맞벌이 가정의 아이들이 부모님이 집에 계시지 않을 때에도 부모님의 목소리를 출력하는 알림으로 안정감을 느끼게 한다. 동시에 기본적인 생활 습관을 들이고, 로봇과의 기초 영어회화를 하며 일찍이 영어에 흥미를 느낄 수 있도록 하는 것이 목적이다.

차원계수방식에 의한 다차원적 빈곤 측정 (Measurement of Multidimensional Poverty by Counting Approach)

  • 최균;서병수;권종희
    • 한국사회복지학
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    • 제63권1호
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    • pp.85-111
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    • 2011
  • 다차원적 빈곤접근에 있어 빈자의 구분방식에는 복합지수방식, 합집합 및 교집합방식이 있는데 이들 방식들은 타당하지 않은 문제들이 있었다. Alkire와 Foster는 이 문제를 해소하는 방법으로 합집합과 교집합의 중간 형태로서 결핍차원들의 개수를 경계선으로 이용하는 차원계수방식을 이론화하였다. 차원계수방식에 의해 우리나라의 다차원적 빈곤을 측정한 결과, 3개 결핍차원을 정책적 차원빈곤선으로 하는 경우 다차원적 빈곤율은 20% 수준으로서 10명 중 2명이 다차원적으로 빈곤하였다. 다차원적 빈곤율이 높은 것은 자산, 소득, 사회보장, 건강 등 여러 차원으로 결핍의 폭이 넓은데 기인하였다. 여성, 한 부모, 노인, 비경제활동인구 등 취약계층일수록 다차원 빈곤의 폭이 넓고 가중되고 있었다. 연구결과 현행 기초생활보장제도가 탈 빈곤유도와 기초생활보장이라는 두 가지 정책목표를 각각 효과적으로 달성하기 위해서는 근로능력 유무에 따라 수급자선정과 지원체제를 이원화하고 차원계수방식을 적용하는 것이 유용하다고 본다.

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