• Title/Summary/Keyword: division into periods

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EFFECT OF EGG WEIGHT AND PRE-INCUBATION HOLDING PERIODS ON HATCHABILITY OF JAPANESE QUAIL EGGS IN DIFFERENT SEASONS

  • Salah Uddin, M.;Paul, D.C.;Huque, Q.M.E.
    • Asian-Australasian Journal of Animal Sciences
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    • v.7 no.4
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    • pp.499-503
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    • 1994
  • One thousand and eighty eggs of Japanese quail (Coturnix coturnix Japonica) were set into the incubator maintaining 36 treatment groups (3 egg weight groups ${\times}3$ seasons ${\times}4$ preincubation holding periods) to evaluate their hatchability performances. Holding periods had significant (p<0.05) effect on hatchability and the seasons showed significant (p<0.05) effect on chick weight. All the parameters (except fertility) were significantly (p<0.01) influenced by the egg weight. None of the parameters maintained regular trend with egg weight and pre-incubation holding periods. Significant interactions were not observed on any of the parameters (except fertility) studied. The egg weight maintained significant (p<0.05) negative correlation with fertility and positive correlation with chick weight. Eggs of medium weight (9.10 to 10.00 cm) could be hatched satisfactorily between 4 and 7 days of pre-incubation holding periods in any season of the year.

Lactic Acid Bacteria Mixture as Inoculants on Low Moisture Italian Ryegrass Silage Fermentation

  • Soundharrajan, Ilavenil;Kuppusamy, Palaniselvam;Park, Hyung Soo;Kim, Ji Hea;Kim, Won Ho;Jung, Jeong Sung;Choi, Ki Choon
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.39 no.3
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    • pp.127-131
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    • 2019
  • The effects of lactic acid bacteria (LAB) mixtures on low moisture Italian ryegrass (IRG) silage fermentation was evaluated in field conditions. The experiment was categorized into two groups: Un-inoculated (Control) and Inoculated with LAB mixture for four storage periods (45, 90, 180, and 365 days, respectively). Silage inoculated with the LAB mixture had the lowest pH with highest lactic acid production than the control from beginning at 45-365 days at all moistures. Higher LAB counts were observed in inoculated silages than the control silages at whole experimental periods. It is a key reason for the rapid acidification and higher lactic acid production in silages during the storage periods. Overall results suggest that an adding of LAB mixture had positive effects on the increasing aerobic stability of silage and preserved its quality for an extended duration.

Comparison of Community Structure of Fish Larvae in the Northern East China Sea in Normal and El Niño/La Niña Periods (엘리뇨/라니냐와 정상 기간 동중국해 북부해역의 자치어의 군집구조 비교)

  • Yoo, Joon-Taek;Choi, Jung-Hwa;Kim, Jin-Yeong;Kim, Jong-Bin;Choi, Kwang-Ho
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.46 no.6
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    • pp.907-916
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    • 2013
  • The aim of this study was to compare community structure of larval fish species in the northern East China Sea during normal meteorological conditions in autumn 2009, during the El Ni$\tilde{n}$o period in 2009-2010, and during the La Nina period in 2010. Fifty taxa were recorded during the study period; the most dominant species were Benthosema pterotum and Gobiidae spp. In October 2008 during the normal period, warm water from the Tsushima Warm Current (TWC) intruded more into the surface and middle layers, and cold water affected by the Yellow Sea Cold Water (YSCW) intruded into the bottom layer. In October 2009 during the El Ni$\tilde{n}$o period, intrusion of the China Coastal Water (CCW), which has low salinity (<32.2 psu), was more apparent than intrusion of the TWC or YSCW. In October 2010 during the La Nina period, intrusion of the TWC and CCW was relatively weak, resulting in the lowest temperature and highest salinity observed during the study period in the eastern part of the study area. Hierarchical cluster, one-way ANOSIM (analysis of similarities), and SIMPER (similarity-percentages procedure) analyses provided two main results. First, the abundance of the most dominant larval fish species in autumn of the normal period was greater than that in autumn of the El Ni$\tilde{n}$o/La Nina periods, resulting in a significant difference in ichthyoplankton community structure between the periods. The abundance of Benthosema pterotum increased in the normal period, possibly influenced by the intrusion of cold water from the YSCW; the abundance of species residing in Korean waters (e.g., Gobiidae spp.) probably decreased during the El Ni$\tilde{n}$o/La Nina periods. The second finding was that the abundance of subtropical larval fish in autumn of the normal period was generally larger than that during autumn of the El Ni$\tilde{n}$o/La Nina periods. This could have been induced by the stronger intrusion of warm water from the TWC during the normal period. Although differences in oceanographic conditions between El Ni$\tilde{n}$o and La Nina periods were observed, the differences in ichthyoplankton community structure between the two periods were not significant.

The method of period division and range setting for annual river discharge management (연중 하천유량 관리를 위한 기간 구분 및 관리범위 설정 방안)

  • Park, Tae Sun
    • Journal of Korea Water Resources Association
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    • v.56 no.1
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    • pp.1-9
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    • 2023
  • Until now, the periods of river discharge management throughout a year are divided into flood and non-flood periods, and the ranges of discharges to be managed are broadly defined from drought discharge to flood discharge. In this study, using the long-term daily discharge data from 8 points of four major rivers, we propose a method of dividing the year into several periods with the homogeneous mean and dispersion of discharges. As a result of the study, the period of through a year was different depending on the point, but it could be divided into pre-flood period, flood period, and post-flood period. And the more subdivided the period, the more decreased the ratio of the maximum discharge to the minimum discharge. In addition, in order to ensure that the discharge for a year is more than the drought discharge and less than the flood discharge, to set the range of discharge management per period as the average flow ± standard deviation for each period is proposed.

Short-Term Load Forecast for Summer Special Light-Load Period (하계 특수경부하기간의 단기 전력수요예측)

  • Park, Jeong-Do;Song, Kyung-Bin
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.62 no.4
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    • pp.482-488
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    • 2013
  • Load forecasting is essential to the economical and the stable power system operations. In general, the forecasting days can be classified into weekdays, weekends, special days and special light-load periods in short-term load forecast. Special light-load periods are the consecutive holidays such as Lunar New Years holidays, Korean Thanksgiving holidays and summer special light-load period. For the weekdays and the weekends forecast, the conventional methods based on the statistics are mainly used and show excellent results for the most part. The forecast algorithms for special days yield good results also but its forecast error is relatively high than the results of the weekdays and the weekends forecast methods. For summer special light-load period, none of the previous studies have been performed ever before so if the conventional methods are applied to this period, forecasting errors of the conventional methods are considerably high. Therefore, short-term load forecast for summer special light-load period have mainly relied on the experience of power system operation experts. In this study, the trends of load profiles during summer special light-load period are classified into three patterns and new forecast algorithms for each pattern are suggested. The proposed method was tested with the last ten years' summer special light-load periods. The simulation results show the excellent average forecast error near 2%.

Species composition and community structure of benthic crustacean assemblage around Oryukdo in southeastern waters off Korea (오륙도 주변해역 저서 갑각류 (Crustacea)의 종조성과 군집구조)

  • Heo, Yu-Sim;Choi, Jung-Hwa;Kim, Jung-Yun;Lee, Dong-Woo
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.50 no.4
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    • pp.604-613
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    • 2014
  • Community structures and species composition in benthic crustacean around Oryukdo of Busan was investigated using a SCUBA diving in 2011. A total 115 species, 51 families, and 4 taxa were collected during the sampling periods. Species were included 52 species in amphipoda, 49 in decapoda, 8 in isopoda and 6 in thoracica. On cluster analysis, the benthic crustacea community was classified into three groups based on the species composition: group A occurred in spring, group B in autumn and winter and group C in summer. Species composition in benthic crustacean corresponded with the water temperature.

Two Dimensional Electronic Spectroscopy

  • Fleming, Graham R.;Yang, Min-O;Agarwal, Ritesh;Prall, Bradley S.;Kaufman, Laura J.;Neuwahl, Fred
    • Bulletin of the Korean Chemical Society
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    • v.24 no.8
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    • pp.1081-1090
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    • 2003
  • Two different electronically resonant two-dimensional spectroscopies are described. The first, two-color photon echo peak shift spectroscopy, is sensitive to correlations in transition frequency between the initial and probed (final) states. It provides new insight into the mechanism of ultrafast solvation and should prove useful for characterizing dynamics in inhomogeneous systems in general. The second technique, fifth order threepulse scattering, contains two coherence periods whose durations are controlled. The entire two-dimensional surface was recorded for a dye molecule in dilute solution and a photosynthetic light-harvesting complex. The data provide insight into the short-time dynamics of solvation and exciton relaxation, respectively.

Effects of Interrupted Wetness Periods on Conidial Germination, Germ Tube Elongation and Infection Periods of Botryosphaeria dothidea Causing Apple White Rot

  • Kim, Ki Woo;Kim, Kyu Rang;Park, Eun Woo
    • The Plant Pathology Journal
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    • v.32 no.1
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    • pp.1-7
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    • 2016
  • Responses of Botryosphaeria dothidea to interrupted wetness periods were investigated under in vivo and in vitro conditions. Conidia of B. dothidea were allowed to germinate on apple fruits under wetting condition at $25^{\circ}C$ for 5 hr. They were air-dried for 0, 1, 2 or 4 hr, and then rewetted at $25^{\circ}C$ for 5 hr. Following an initial wetness period of 5 hr, 83% of the conidia germinated. The percent conidial germination increased to 96% when wetting was extended continuously another 5 hr. However, no further conidial germination was observed when wetting was interrupted by dry periods of 1, 2 and 4 hr, resulting in 83, 81 and 82%, respectively. The mean length of the germ tubes was $37{\mu}m$ after 5 hr of wetting and elongated to $157{\mu}m$ after 10 hr of continuous wetting. On the other hand, interruption of wetting by a dry period of 1 hr or longer after the 5 hr of initial wetting arrested the germ tube elongation at approximately $42{\mu}m$ long. Prolonged rewetting up to 40 hr did not restore germ tube elongation on slide glasses under substrate treatments. Model simulation using weather data sets revealed that ending infection periods by a dry period of at least 1 hr decreased the daily infection periods, avoiding the overestimation of infection warning. This information can be incorporated into infection models for scheduling fungicide sprays to control apple white rot with fewer fungicide applications.

Use of Androgenesis in Haploid Breeding

  • Yi, Gihwan;Kim, Kyung-Min;Sohn, Jae-Keun
    • Current Research on Agriculture and Life Sciences
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    • v.31 no.2
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    • pp.75-82
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    • 2013
  • Haploids are plants with a gametophytic number of chromosomes in their sporophytes. Androgenesis occurs from asymmetric division of pollen grains into generative cells and vegetative cells, followed by re-entry of the vegetative cell during S-phase, which causes microspores progress into G2/M transition in culture. One of the most interesting features of haploids is the possibility to produce doubled haploid (DH) individuals. Doubled haploidy is extremely useful to plant breeders because it enables shortened breeding periods and efficiency in selection of useful recessive agronomic traits. Doubled-haploid technology is not only applicable to breeding, but also to transformation programs of desired genes. In addition to practical breeding programs, DH lines provide useful materials of fundamental genetics including exploitation of QTLs and genes conferred with various agronomic traits by establishing DH populations. This paper provides historical overviews on androgenesis and describes several mechanisms associated with pollen embryogenesis, including mode of actions in pollen embryogenesis, mechanisms of chromosome doubling and factors affecting androgenesis. We also discuss recent progress in application of haploids to breeding, genes associated with in vitro response and drawbacks to anther culture for application of doubled haploids in crop breeding.

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Change in Hanbok of South and North Korea after the Division and the Interexchange -Focusing on Women's Jeogori- (분단과 교류이후 남북한 한복에 나타난 변화 -여자 저고리 중심으로-)

  • Chang, In-Woo
    • Journal of the Korean Society of Clothing and Textiles
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    • v.30 no.1 s.149
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    • pp.106-114
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    • 2006
  • This research aims to identify the recent changes in construction, design, and technical vocabularies between North and South Korea of the Korean woman's top(Jeogori), which is a main part of her traditional costume(Hanbok). After Korea War, Korea was divided into two countries(the division), and there was little communication between the two until 1972(the interexchange). Thus, this study will compare two time periods: 1953-1972 and 1972 to recent times. Hanbok construction books published in both Koreas are evaluated here to see what similarities and differences existed during these two periods. Women in the North continued to wear their traditional costume(renamed the Chosunot in the North) as daily clothing, but women in the South began saving the Hanbok only for parties and ceremonies. As the North Korean government controlled its peoples dress and continued to make changes, the North kept developing new technical vocabularies, but the South continued to use the same terms fur the Hanbok. From the end of the 1990s, the Chosunot had become more and more similar to the Hanbok in colors, shapes, and materials.