• 제목/요약/키워드: Family of distributions

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한국산 청어과 어류의 분류학적 연구 (Taxonomic Revision of the Family Clupeidae(Pisces: Clupeiformes) from Korea)

  • 윤창호;김익수
    • 한국어류학회지
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    • 제10권1호
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    • pp.49-60
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    • 1998
  • 한국산 청어과(科) 어류에 대한 분류학적인 재검토를 실시하기 위하여 우리나라 연안 22개 지점에서 채집하거나 국외에서 입수한 표본에 대한 계수 계측형질을 중심으로 연구를 수행하였다. 본 조사결과, 한국산 청어과(科)는 10속(屬) 11종(種)으로 확인되었다. Pristigaster 속(屬) 어류는 남미의 담수역에서만 분포 서식하며, 배지느러미가 없는 특정을 지니고 있어 Chyung (1977)이 보고한 때치 Pristigaster chinensis는 준치의 동종이명으로 확인되었다. 청어과(科) 어류의 학명을 재검토한 결과, 눈퉁멸의 학명은 Etrumeus micropus에서 E. teres (De Kay, 1842)로, 샛줄멸은 Spratelloides japonicus에서 S. gracilis (Temminck et Schlegel, 1846), 이와치는 Sardinella immaculata에서 S. jussieu (Valenciennes, 1847)로, 밴댕이는 Harengula zunasi 에서 Sardinella zunasi (Bleeker, 1854) 및 납작전어는 Macrura reevesii에서 Tenualosa reevesii (Richardson, 1846)로 확인되어, 이들의 학명을 변경하였다. 청어과(科) 어류는 우리나라 전해역에서 고르게 출현하였으며, 비교적 전 해역에서 고르게 출현하는 종은 전어 Konosirus punctatus와 밴댕이 Sardinella zunasis로 확인되었고, 한국산 고유종은 없었다.

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가족계획 우수.부진지역 사례연구 (A Case Study on High and Low Performance Areas for Family Planning)

  • 홍성열;김태일
    • 한국인구학
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    • 제4권1호
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    • pp.105-130
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    • 1981
  • This study was conducted to compare the characteristics of high performane areas for family planning with that of low performance areas and to find factors which strongly affected contraceptive practice behavior. For the study, eight areas were selected from 274 rural family planning canvassing areas of Korean Population Policy and Program Evaluation Study, which was an action study operated in all areas of Cheju Island from July 1, 1976 until December 31,1979. As a first step of the action study, Cheju Island was devided up 318 family planning canvasser areas Each area was consisted of 200 households in rural district and 300 households in urhan one Duriog the period of project, each canvassing area had been managed by a female family planning canvasser, selected by director of health center considering several individual conditions needed for family planning activities Basic activities of canvassers were to counsell all the eligihie couples in own charged area about family planning methods and also to distribute contraceptives such as condoms and oral pills. In case couples desire to accept sterilization including vasectomy and tubal-ligation, the canvassers played a linking role connecting potential client with family planning field workers. Canvassng areas shows significant differentce in performance for family planning, nevertheless they are supposed to have almost the same conditions regarding family planning distribution channel. Because the purpose of the Cheju project was to eliminate all the problems that existed in governmental distribution system, that is to remove geographic, economic, cognitive and administrative barriers Accumulated performances of family planning methods accepted by residents in each area were calculated by eligible women aged 14-49. And then canvassing areas were ranked according to performance score. Consequently, 4 areas in extremely high and low family planning performance areas were selected respectively. Major results were obtained by comparing characteristics of high performance area with that of low performance areas, which are as follows: 1. The mean number of living children was about the same both in high and low performance areas for family planning. But respondents' mean age (38.5) in high performance areas was higher than that (37.0) in low performance areas 2. Respondents' perception in the expectant educational level of others' children in high performance areas was higher than that in low performance areas, although respondents educational level, monthly expenditure and ratio of children in high school and above was not different. 3. Ratio of ownerships of TV and newspaper in high performance areas was highen than that in low performance areas 4. The duration of canvasser' charge in high performance areas was longer than that of low performance areas, showing the fact that canvassers didn't move cut in high performance areas 5. In high performance areas, canvassers' houses were relatively located in the center part of the village. And so villagers resided in near distances from the anvasser's house 6. 4H clubs' activities in high performance areas were more active than those in low performance areas Therefore it was assumed that cohesiveness of community in high performance areas were stronger than that in low areas. 7. Canvassers' family planning practice rate was higher than that in low performance areas, and also canvassers' human relationship was more sociable than that of canvassers in low performance areas. 8. Fourteen variables which showed relatively high significance level in $X^2$ and F test were selected as independent variables for stepwise regression analysis. According to the results of regression analysis. five of 14 variables-distributors education level ($R^2$=.4439), duration of distributor's charge ($R^2$=.6166), 4H club activities ($R^2$=.6697), canvasser's contraceptive practice ($R^2$=.7377) and location of distributions house ($R^2$=.8010) explained 80.1 percent of total variance.

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Use of Flattening Filter Free Photon Beams for Off-axis Targets in Conformal Arc Stereotactic Body Radiation Therapy

  • Smith, Ashley;Kim, Siyong;Serago, Christopher;Hintenlang, Kathleen;Ko, Stephen;Vallow, Laura;Peterson, Jennifer;Hintenlang, David;Heckman, Michael;Buskirk, Steven
    • 한국의학물리학회지:의학물리
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    • 제25권4호
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    • pp.288-297
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    • 2014
  • Dynamic conformal arc therapy (DCAT) and flattening-filter-free (FFF) beams are commonly adopted for efficient conformal dose delivery in stereotactic body radiation therapy (SBRT). Off-axis geometry (OAG) may be necessary to obtain full gantry rotation without collision, which has been shown to be beneficial for peripheral targets using flattened beams. In this study dose distributions in OAG using FFF were evaluated and the effect of mechanical rotation induced uncertainty was investigated. For the lateral target, OAG evaluation, sphere targets (2, 4, and 6 cm diameter) were placed at three locations (central axis, 3 cm off-axis, and 6 cm off-axis) in a representative patient CT set. For each target, DCAT plans under the same objective were obtained for 6X, 6FFF, 10X, and 10FFF. The parameters used to evaluate the quality of the plans were homogeneity index (HI), conformality indices (CI), and beam on time (BOT). Next, the mechanical rotation induced uncertainty was evaluated using five SBRT patient plans that were randomly selected from a group of patients with laterally located tumors. For each of the five cases, a plan was generated using OAG and CAG with the same prescription and coverage. Each was replanned to account for one degree collimator/couch rotation errors during delivery. Prescription isodose coverage, CI, and lung dose were evaluated. HI and CI values for the lateral target, OAG evaluation were similar for flattened and unflattened beams; however, 6FFF provided slightly better values than 10FFF in OAG. For all plans the HI and CI were acceptable with the maximum difference between flattened and unflattend beams being 0.1. FFF beams showed better conformality than flattened beams for low doses and small targets. Variation due to rotational error for isodose coverage, CI, and lung dose was generally smaller for CAG compared to OAG, with some of these comparisons reaching statistical significance. However, the variations in dose distributions for either treatment technique were small and may not be clinically significant. FFF beams showed acceptable dose distributions in OAG. Although 10FFF provides more dramatic BOT reduction, it generally provides less favorable dosimetric indices compared to 6FFF in OAG. Mechanical uncertainty in collimator and couch rotation had an increased effect for OAG compared to CAG; however, the variations in dose distributions for either treatment technique were minimal.

ON ESTIMATION OF NEGATIVE POLYA-EGGENBERGER DISTRIBUTION AND ITS APPLICATIONS

  • Hassan, Anwar;Bilal, Sheikh
    • Journal of the Korean Society for Industrial and Applied Mathematics
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    • 제12권2호
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    • pp.81-95
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    • 2008
  • In this paper, the negative Polya-Eggenberger distribution has been introduced by compounding negative binomial distribution with beta distribution of I-kind which generates a number of univariate contagious or compound (or mixture of) distributions as its particular cases. The distribution is unimode, over dispersed and all of its positive and negative integer moments exist. The difference equation of the proposed model shows that it is a member of the Ord's family of distribution. Some of its interesting properties have been explored besides different methods of estimation been discussed. Finally, the parameters of the proposed model have been estimated by using a computer programme in R-software. Application of the proposed model to some data, available in the literature, has been given and its goodness of fit demonstrated.

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An Adaptive Approach to Learning the Preferences of Users in a Social Network Using Weak Estimators

  • Oommen, B. John;Yazidi, Anis;Granmo, Ole-Christoffer
    • Journal of Information Processing Systems
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    • 제8권2호
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    • pp.191-212
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    • 2012
  • Since a social network by definition is so diverse, the problem of estimating the preferences of its users is becoming increasingly essential for personalized applications, which range from service recommender systems to the targeted advertising of services. However, unlike traditional estimation problems where the underlying target distribution is stationary; estimating a user's interests typically involves non-stationary distributions. The consequent time varying nature of the distribution to be tracked imposes stringent constraints on the "unlearning" capabilities of the estimator used. Therefore, resorting to strong estimators that converge with a probability of 1 is inefficient since they rely on the assumption that the distribution of the user's preferences is stationary. In this vein, we propose to use a family of stochastic-learning based Weak estimators for learning and tracking a user's time varying interests. Experimental results demonstrate that our proposed paradigm outperforms some of the traditional legacy approaches that represent the state-of-the-art technology.

Divergent long-terminal-repeat retrotransposon families in the genome of Paragonimus westermani

  • Bae, Young-An;Kong, Yoon
    • Parasites, Hosts and Diseases
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    • 제41권4호
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    • pp.221-231
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    • 2003
  • To gain information on retrotransposons in the genome of Paragonimus westermani, PCR was carried out with degenerate primers, specific to protease and reverse transcriptase (rt) genes of long-terminal-repeat (LTR) retrotransposons. The PCR products were cloned and sequenced, after which 12 different retrotransposon-related sequences were isolated from the trematode genome. These showed various degrees of identity to the polyprotein of divergent retrotransposon families. A phylogenetic analysis demonstrated that these sequences could be classified into three different families of LTR retrotransposons, namely, Xena, Bel, and Gypsy families. Of these, two mRNA transcripts were detected by reverse transcriptase-PCR, showing that these two elements preserved their mobile activities. The genomic distributions of these two sequences were found to be highly repetitive. These results suggest that there are diverse retrotransposons including the ancient Xena family in the genome of P. westermani, which may have been involved in the evolution of the host genome.

Burning of Metallized Composite Solid Rocket Propellants: from Micrometric to Nanometric Aluminum Size

  • DeLuca, Luigi T.;Galfetti, Luciano
    • 한국추진공학회:학술대회논문집
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    • 한국추진공학회 2008년 영문 학술대회
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    • pp.886-898
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    • 2008
  • A survey is offered of the present status of microaluminized propellants industrially used worldwide in most space applications, but new directions are also pointed out making profitable use of the nanoaluminized propellants currently tested in many laboratories. Different industrial- and research-type of solid rocket propellants, mainly but not only, of the well-known family oxidizer/Al/HTPB(oxidizer being AP, AN or a mixture of the two) were experimentally analyzed at the Space Propulsion Laboratory of Politecnico di Milano. In general, they feature the same nominal composition but implement different grain size distributions of the oxidizer or metal fuel. The basic properties of all formulations were compared to that of a standard propellant already certified for flight.

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New Record of Diatom Species in Korean Coastal Waters

  • Lee, Sang Deuk;Park, Joon Sang;Lee, Jin Hwan
    • 환경생물
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    • 제30권3호
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    • pp.245-271
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    • 2012
  • A study on the indigenous diatoms was carried out at 103 sites during August 2008 to April 2011 from the marine and the brackish waters in Korea. A fine structure of small-sized diatoms was examined using a light and scanning electron microscopy. Sixty species of diatoms were newly identified and composed of 3 class, 6 subclass, 16 order, 21 family and 39 genus. The detailed nomenclatures, references, photographs and distributions were here reported. Of 60 species, the most frequent species was Tryblionella coarctata appearing 24 times, and 22 times followed by Thalassiosira lacustris, Cocconeis stauroneiformis was 20 times. In the level of genus, Chaetoceros, Parlibells and Thalassiosira were included 4 species, Actinocyclus, Minidiscus and Licmophora were included 3 species. This study will provide the knowledge of the diversity level of diatom in Korea, the knowledge is important on the diatoms for further studies.

역학과 사회역학 (Epidemiology and Social Epidemiology)

  • 송윤미
    • Journal of Preventive Medicine and Public Health
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    • 제38권3호
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    • pp.237-240
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    • 2005
  • Social epidemiology is a sub-discipline of epidemiology explicitly investigating social determinants of population distributions of health, disease, and well-being. Persistent pattern of social inequalities in health in spite of the broad improvement in the physical environment over the last centuries necessitated the development of this field as an approach to understand disease etiology that incorporates social experiences as more direct determinant of health. Social epidemiology incorporates theories, measurement tools, and techniques from a wide variety of other social sciences. A population perspective, the social context of behavior, contextual multilevel analysis, a developmental and life-course perspective, and general susceptibility to disease are the most important guiding concepts in social epidemiology.

First Report of Two Diogenid Species of Hermit Crabs (Crustacea: Decapoda: Anomura) from Korea

  • Jung, Jibom;Kim, Won
    • Animal Systematics, Evolution and Diversity
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    • 제31권2호
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    • pp.107-113
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    • 2015
  • Two diogenid hermit crab species, Dardanus lagopodes and Diogenes deflectomanus, are newly reported from Korea. Dardanus lagopodes is distinguished from the other species of genus Dardanus in Korea by having setae with cream-colored tips on the cephalothorax and the following characteristics: ocular peduncles somewhat longer than antennular peduncles, and the pereopod without a longitudinal sulcus and scute-like projections. Diogenes deflectomanus is similar to D. nitidimanus but can be distinguished by having the fixed finger of the left cheliped bent slightly downwardly and the following characteristics: slightly shorter ocular peduncle, elongated left cheliped with small granules on the surface, right cheliped without calcareous teeth on the cutting edge of the dactylus, and the minute spine of post-median margin of the telson is not well developed. The geographical distributions of these two species are extended by the present study. In particular, D. deflectomanus in the current study is the first report outside Chinese waters. Now, 20 species of the family Diogenidae are known in Korean waters.