• Title/Summary/Keyword: For the first time in Korea

Search Result 8,726, Processing Time 0.05 seconds

The first record of Bouchetriphora consfera (Caenogastropoda, Triphoridae) from Korean Waters

  • Kil, Hyun-Jong;Lee, Jun-Sang
    • The Korean Journal of Malacology
    • /
    • v.28 no.3
    • /
    • pp.275-276
    • /
    • 2012
  • The specimens of triphorid snail, Bouchetriphora consfera were collected from Jeju-do, Korea and diagnostic characters were analysed. As a result, the genus Bouchetriphora is reported for the first time in Korean malacol fauna and the family Triphoridae in Korea turned out to be 15 species of 10 genera.

Approximate Method in Estimating Sensitivity Responses to Variations in Delayed Neutron Energy Spectra

  • J. Yoo;H. S. Shin;T. Y. Song;Park, W. S.
    • Proceedings of the Korean Nuclear Society Conference
    • /
    • 1997.10a
    • /
    • pp.85-90
    • /
    • 1997
  • Previous our numerical results in computing point kinetics equations show a possibility in developing approximations to estimate sensitivity responses of nuclear reactor We recalculate sensitivity responses by maintaining the corrections with first order of sensitivity parameter. We present a method for computing sensitivity responses of nuclear reactor based on an approximation derived from point kinetics equations. Exploiting this approximation, we found that the first order approximation works to estimate variations in the time to reach peak power because of their linear dependence on a sensitivity parameter, and that there are errors in estimating the peak power in the first order approximation for larger sensitivity parameters. To confirm legitimacy of our approximation, these approximate results are compared with exact results obtained from our previous numerical study.

  • PDF

Influence of Geometric Initial Imperfection on the First Buckling Time Variation of Cylinder Under Impact Load (충격하중을 받는 원통의 최초좌굴시간의 변동성에 대한 기하학적 초기결함의 영향)

  • 김두기
    • Computational Structural Engineering
    • /
    • v.10 no.1
    • /
    • pp.173-183
    • /
    • 1997
  • In this paper a method is suggested for the probabilistic analysis of impact buckling failure time of cylinder with random axisymmetric geometric imperfection under axial impact. Failure is assumed as axisymmetric radial deformation exceeds the given criteria for the first time. For the generation of random geometric initial imperfection, random field theory by mean function and autocorrelation function of geometric imperfection is used. Suggested method is useful for the treatment of the randomness of realistic geometric imperfection and can be used for the structural safety analysis of cylinder considering its effect.

  • PDF

Study on Milkability Traits in Holstein Cows

  • Lee, D.H.;Choudhary, V.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.19 no.3
    • /
    • pp.309-314
    • /
    • 2006
  • The present investigation was undertaken to study the milkability characteristics of Holstein cows. Out of 6,660 initial records 4,607 records were finally included in the analysis after deleting some records with an abnormal range of values for the traits considered. These 4,607 Holstein cows belonged to a total of 122 herds located in a province in Korea. The 'LactoCorder' instrument was used to electronically record the milkability traits at the milking parlor. A total of 19 traits were studied which were broadly classified into milk yield, milking speed, milking time and the electrical conductivity related traits. The SAS 9.1 statistical software was used to carry out analyses. The average maximum milk flow per minute was 3.21 kg/min, while the average milking speed during the main milking process (DMHG) had a mean value of 2.30 kg/min. The total milk yield was 14.14 kg, 62% of which was milked during the first three minutes of the milking. The average total milking time was 8.23 min. Among the three phases of the main milking process, the time of stable milk flow had the longest time (2.97 min) followed by the time at the decline phase (2.62 min). The average time taken to reach the plateau phase was 1.08 min, which can still be reduced further through improved managemental practices. Among milk yield traits, milk yield during the first two (MG2) and three (MG3) minutes of milking had high positive correlation with milking speed traits and negative correlations with almost all the milking time traits except time of incline in milk flow from 0.5 kg/min till the attainment of the plateau phase (tAN). Milking speed traits had negative correlations with total milking time, time at main milking process, time at plateau and with the time at decline. Since there was medium to high negative correlation between the milking speed and the time at plateau, there is a need for selection of cows which have intermediate milking speed so that it could require less milking time and also the optimum (higher and longer) plateau time. Proper pre-stimulation and avoiding over milking will help in further reducing the milking time and thus will add to the net profit of the farmer.

First records of the genera Tillus and Elasmocylidrus (Coleoptera: Cleridae) in Korea, with Tillus elongatus (Linnaeus, 1758) and Elasmocylidrus takedaorum Murakami and Gerstmeier, 2020

  • JUNG, Boo Hee
    • International Journal of Industrial Entomology and Biomaterials
    • /
    • v.43 no.1
    • /
    • pp.1-5
    • /
    • 2021
  • Two genera of the family Cleridae, Tillus Olivier, 1790 and Elasmocylidrus Corporaal, 1939 and two species, Tillus elongatus (Linnaeus, 1758) and Elasmocylidrus takedaorum Murakami and Gerstmeier, 2020 are reported for the first time in Korea. Illustrations of a habitus, diagnostic characteristics of the genus and species are presented with key to the korean genera of subfamily Tillinae.

Factors Associated with Use and Types of Multiple Concurrent Care and Education Arrangements in Early Childhood in South Korea

  • An, Miyoung
    • International Journal of Human Ecology
    • /
    • v.15 no.2
    • /
    • pp.81-92
    • /
    • 2014
  • This paper explores factors associated with multiple concurrent care and education arrangements in early childhood in South Korea. It draws on a subsample from the Korean Longitudinal Survey of Women and Families. Results show that about one-fifth of the families utilized multiple arrangements for their first preschool child. The primary non-parental option in multiplicity was nurseries or kindergartens. Home care and education options such as home study materials were found to be most prevalent secondary non-parental option, followed by services at private institution as well as relative care. Children's age, care cost, non-parental care time and time constraints were found to be positively related to the incidence of multiplicity for the first preschool child while family income and cost constraints were negatively associated. As a secondary option in the multiplicity, services at private institutions increased with children's age, care cost and when the grandparents live far from the parents' house. Home care and education utilization was found more among mothers with low degree of time constraints. Utilization of relative support decreased with the children's age and meant lower care cost and increased with mother's employment, fathers' education, family income, cost constraints and when grandparents live nearby. This paper, based on the associated factors, suggests how issues of children enrichment and constraints might be related to the multiplicity.

First Record of Psen ussuriensis (Hymenoptera: Crabronidae: Pemphredoninae) from Korea, with a Key and Checklist of Current Valid Species of Korean Pemphredoninae

  • Kim, Jeong-Kyu;Yang, Hyeon-Woo
    • Animal Systematics, Evolution and Diversity
    • /
    • v.26 no.2
    • /
    • pp.141-151
    • /
    • 2010
  • Psen ussuriensis Lith is reported for the first time in Korea. Diagnostic description and digital images of this species are provided. For future researchers, a key to higher taxa and a checklist of 36 valid Korean Pemphredononae species are also given.

Four unrecorded species of free-living nematodes from the sublittoral zone in the East Sea, Korea

  • Jung-Ho Hong;Kichoon Kim;Seunghan Lee;Kanghyun Lee
    • Journal of Species Research
    • /
    • v.13 no.2
    • /
    • pp.147-158
    • /
    • 2024
  • Four species of the free-living nematodes were collected from marine sediments in the sublittoral zone in the East Sea, Korea and were identified, described, and illustrated. Paranticoma tricerviseta Zhang, 2005, originally described from the Bohai Sea, China, is recorded for the first time in the East Sea, Korea; only in body length and thickness (1902-2282 ㎛ compared to 2472-3300 ㎛, 50-62 ㎛ compared to 57-82 ㎛, respectively). Specimens of Parodontophora marina Zhang, 1991, from East Sea, Korea largely agrees with the original description of Zhang (1991) of nematodes from the Bohai Sea, except for differences in body length and thickness (1190-1345 ㎛ compared to 1235-1408 ㎛, 40-44 ㎛ compared to 42-72 ㎛). Terschellingia longicaudata de Man, 1907 is reported for the first time in Korea, but was previously considered a cosmopolitan species of nematodes with a widespread distribution from the North Sea, Belgium to the Exclusive Economic Zone of New Zealand; it differs from the original description in body thickness(30-38 ㎛ vs. 40-62 ㎛). Vasostoma brevispicula Huang & Wu, 2011, originally described from the subtidal muddy sediment in the Yellow Sea, China, is newly reported in Korea; apart from a few minor morphological differences, body length and thickness (2009-2425 ㎛ vs. 2119-2906 ㎛, 41-48 ㎛ vs. 37-58 ㎛). The present study on unrecorded species improves our understanding of nematode species diversity in Korean waters.

A Taxonomy of the Common Tasks and the Development of a Risk Index for Physical Load Assessment in Nursing Job

  • Ryoo, Jang Jin;Lee, Kyung-Sun;Koo, Jung-Wan
    • Safety and Health at Work
    • /
    • v.11 no.3
    • /
    • pp.335-346
    • /
    • 2020
  • Background: Nursing service is a nonroutine work with an excessive physical load and diverse tasks. This study derived representative common tasks based on the frequently occurring tasks with a high physical load in the nursing workers' daily work and developed indicators to evaluate the work risk by reflecting the characteristics of nonroutine work. Methods: Common tasks were classified through the following stages: literature review, first focus group interview (FGI) with experts, first classification of common tasks, second FGI with hospital health managers, a survey of nursing service workers, and the final classification of common tasks for each task type. To develop an objective risk index for physical load assessment, we investigated the frequency and duration of the derived common tasks via survey. Results: Nursing common tasks were categorized into six task types and 56 subtasks. To evaluate the risks of various tasks in nonroutine works, three frequencies and three working time levels were defined by examining the task frequency and working hours. Exposure time was defined to reflect the characteristics of a nonroutine job. The final risk assessment was the product of the exposure time level and job intensity level. From this, four risk action levels were derived. Conclusion: This study has the advantage of solving the problem of focusing on some tasks in evaluating the physical load. It was meaningful in that a new risk assessment index based on exposure time was proposed based on the development of an evaluation scale for frequency and time by reflecting the characteristics of nonroutine work.

Nonlinear Canonical Correlation Analysis of the Korea Precipitaiton with Sea Surface Temperature near East Asia

  • Kim, Gwang-Seob;Mingdong, Sun
    • Proceedings of the Korea Water Resources Association Conference
    • /
    • 2010.05a
    • /
    • pp.1620-1624
    • /
    • 2010
  • The NLCCA has been applied to analyze the East Asia sea surface temperature (SST) and Korea monthly precipitation, where the eight leading PCs of the SST and the eight PCs of the precipitation during 1973-2007 were inputs to an NLCCA model. The first NLCCA mode is plotted in the PC spaces of the Korea precipitation and the world SST present a curve linking the nonlinear relationship between the first three leading PCs of Korea precipitation and world SST forthright. The correlation coefficient between canonical variate time series u and v is 0.8538 for the first NLCCA mode. And there are some areas' climate variability have higher relationship with Korea precipitation, especially focus on the north of East Sea' climate variability have represented the higher canonical correlation with Korea precipitation, with the correlation coefficient is 0.871 and 0.838. Likewise in Korea, most stations display similarly uniform distributing characteristic and less difference, in particular the inshore stations have display identical distributing characteristic. In correlation variables' scores, the fluctuation and variation trend are also seasonal oscillation with high frequency.

  • PDF