• Title/Summary/Keyword: Peak period

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Reproductive Ecology of the Freshwater Marsh Clam, Corbicula papyracea (Heude) in Bukhan River (북한강 엷은재첩, Corbicula papyracea (Heude) 의 번식생태)

  • Kim, Dae-Hee;Lee, Wan-Ok;Lee, Jun-Sang
    • The Korean Journal of Malacology
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    • v.30 no.2
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    • pp.107-116
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    • 2014
  • Gonadal development and maturation mechanism were studied on the freshwater marsh clam Corbicula papyracea (Heude), which is the endangered species in Korea. The specimens were collected in the rearing ponds and waterway of NFRDI in Gapyeong-gun, Gyeonggi-do from January to December 2004, and then investigated by condition factor, relative growth, gonadal development phases and gonad histological characters based on 30-50 individuals every month. Comparing with the freshwater marsh clam, C. papyracea is small, light olive brown shell and violet interior. The hermaphrodite individuals of C. papyracea take an internal fertilization and fertilized eggs are stored in the foster-sack in the gills, then the hatched juveniles are released outside after an ovoviviparous process. The average water temperature of inhabit area was in range of $1.8-27.0^{\circ}C$ and usually took great effects on the gonad maturation of C. papyracea. The condition factor ranged from 0.14 to 0.21 throughout the year, which was the lowest during winter season (December-February), and gradually increased to the highest value of 0.21 in May. The ratio of meat weight to total weight was 25.9-38.7%, indicating the similar trend with condition factor. The highest values of condition factor and the ratio of meat weight appeared 1-2 months later than gonadosomatic index reached the peak value, it was probably because that the ovoviviparous eggs would spend a long period before hatching from the foster-sack in the gills. To synthesize the characters of meat weight, condition factor and gonad development by histological study, reproductive cycle of C. papyracea could be divided into five successive stages: multiplicative stage (December to February), growing stage (February to May), mature stage (June to August), spawning stage (August to November), recovery stage (November to December). The smallest shell length of matured C. papyracea was 12.6 mm, and individuals, larger than 16 mm, was formed the nursery in the gills.

The Effects of Complex Motor Training on Motor Function and Synaptic Plasticity After Neonatal Binge-like Alcohol Exposure in Rats (복합운동훈련이 신생 흰쥐의 알코올성 소뇌손상 후 운동기능 및 신경연접가소성에 미치는 영향)

  • Lee, Sun-Min;Koo, Hyun-Mo;Kwon, Hyuk-Cheol
    • Physical Therapy Korea
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    • v.12 no.3
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    • pp.56-66
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    • 2005
  • The purposes of this study were to test that complex motor training enhance motor function significantly, to test change in cerebellum, and to test the synaptic plasticity into the immunohistochemistry response of synaptophysin. Using an animal model of fetal alcohol syndrome - which equates peak blood alcohol concentrations across developmental period - the effects of alcohol on body weight during periods were examined. The effect of complex motor training on motor function and synaptic plasticity of rat exposed alcohol on postnatal days 4 through 10 were studied. Newborn rats were assigned to one of two groups: (1) normal group (NG), via artificial rearing to milk formula and (2) alcohol groups (AG), via 4.5 g/kg/day of ethanol in a milk solution. After completion of the treatments, the pups were fostered back to lactating dams, where they were raised in standard cages (two-and three animals per cage) until they were postnatal 48 days. Rats from alcohol group of postnatal treatment then spent 10 days in one of two groups: Alcohol-experimental group was had got complex motor training (learning traverse a set of 6 elevated obstacles) for 4 weeks. The alcohol-control group was not trained. Before consider replacing with "the experiment/study", (avoid using "got" in writing) the rats were examined during four behavioral tests and their body weights were measured, then their coronal sections were processed in rabbit polyclonal antibody synaptophysin. The synaptophysin expression in the cerebellar cortex was investigated using a light microscope. The results of this study were as follows: 1. The alcohol groups contained significantly higher alcohol concentrations than the normal group. 2. The alcohol groups had significantly lower body weights than the normal group. 3. In alcohol groups performed significantly lower than the normal group on the motor behavioral test. 4. In alcohol-control group showed significantly decreased immunohistochemistric response of the synaptophysin in the cerebellar cortex compared to the nomal group. These results suggest that improved motor function induced by complex motor training after postnatal exposure is associated with dynamically altered expression of synaptophysin in cerebellar cortex and that is related with synaptic plasticity. Also, these data can potentially serve as a model for therapeutic intervention.

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Investigation on a Haze Episode of Fine Particulate Matter using Semi-continuous Chemical Composition Data (준 실시간 화학적 조성자료를 이용한 미세입자 연무 에피소드 규명)

  • Park, Seung-Shik;Kim, Sun-Jung;Gong, Bu-Joo;Lee, Kwon-Ho;Cho, Seog-Yeon;Kim, Jong-Choon;Lee, Suk-Jo
    • Journal of Korean Society for Atmospheric Environment
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    • v.29 no.5
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    • pp.642-655
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    • 2013
  • In this study, semi-continuous measurements of $PM_{2.5}$ mass, organic and elemental carbon (OC and EC), black carbon (BC), and ionic species concentrations were made for the period of April 03~13, 2012, at a South Area Supersite at Gwangju. Possible sources causing the high concentrations of major chemical species in $PM_{2.5}$ observed during a haze episode were investigated. The measurement results, along with meteorological parameters, gaseous pollutants data, air mass back trajectory analyses and PSCF (potential source contribution function) results, were used to study the haze episode. Substantial enhancements of OC, EC, BC, $K^+$, $SO{_4}^{2-}$, $NO{_3}{^-}$, $NH{_4}{^+}$, and CO concentrations were closely associated with air masses coming from regions of forest fires in southeastern China, suggesting likely an impact of the forest fires. Also the PSCF maps for EC, OC, $SO{_4}^{2-}$, and $K^+$ demonstrate further that the long-range transport of smoke plumes of forest fires detected over the southeastern China could be a possible source of haze phenomena observed at the site. Another possible source leading to haze formation was likely from photochemistry of precursor gases such as volatile organic compounds, $SO_2$, and $NO_2$, resulting in accumulation of secondary organic aerosol, $SO{_4}^{2-}$ and $NO{_3}{^-}$. Throughout the episode, local wind directions were between 200 and $230^{\circ}C$, where two industrial areas are situated, with moderate wind speeds of 3~5 m/s, resulting in highly elevated concentration of $SO_2$ with a maximum of 15 ppb. The $SO{_4}^{2-}$ peak occurring in the afternoon hours coincided with maximum ambient temperature ($24^{\circ}C$) and ozone concentration (~100 ppb), and were driven by photochemistry of $SO_2$. As a result, the pattern of $SO{_4}^{2-}$ variations in relation to wind direction, $SO_2$ and $O_3$ concentrations, and the strong correlation between $SO_2$ and $SO{_4}^{2-}$ ($R^2=0.76$) suggests that in addition to the impact of smoke plumes from forest fires in the southeastern China, local $SO_2$ emissions were likely an important source of $SO{_4}^{2-}$ leading to haze formation at the site.

Anticipating the Need for Healthcare Resources Following the Escalation of the COVID-19 Outbreak in the Republic of Kazakhstan

  • Semenova, Yuliya;Pivina, Lyudmila;Khismetova, Zaituna;Auyezova, Ardak;Nurbakyt, Ardak;Kauysheva, Almagul;Ospanova, Dinara;Kuziyeva, Gulmira;Kushkarova, Altynshash;Ivankov, Alexandr;Glushkova, Natalya
    • Journal of Preventive Medicine and Public Health
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    • v.53 no.6
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    • pp.387-396
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    • 2020
  • Objectives: The lack of advance planning in a public health emergency can lead to wasted resources and inadvertent loss of lives. This study is aimed at forecasting the needs for healthcare resources following the expansion of the coronavirus disease 2019 (COVID-19) outbreak in the Republic of Kazakhstan, focusing on hospital beds, equipment, and the professional workforce in light of the developing epidemiological situation and the data on resources currently available. Methods: We constructed a forecast model of the epidemiological scenario via the classic susceptible-exposed-infected-removed (SEIR) approach. The World Health Organization's COVID-19 Essential Supplies Forecasting Tool was used to evaluate the healthcare resources needed for the next 12 weeks. Results: Over the forecast period, there will be 104 713.7 hospital admissions due to severe disease and 34 904.5 hospital admissions due to critical disease. This will require 47 247.7 beds for severe disease and 1929.9 beds for critical disease at the peak of the COVID-19 outbreak. There will also be high needs for all categories of healthcare workers and for both diagnostic and treatment equipment. Thus, Republic of Kazakhstan faces the need for a rapid increase in available healthcare resources and/or for finding ways to redistribute resources effectively. Conclusions: Republic of Kazakhstan will be able to reduce the rates of infections and deaths among its population by developing and following a consistent strategy targeting COVID-19 in a number of inter-related directions.

Estimation of Extreme Wind Speeds in Korean Peninsula using Typhoon Monte Carlo Simulation (태풍 시뮬레이션을 통한 한반도 극한풍속 추정)

  • Lee, Sungsu;Kim, Ga Young
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.29 no.2
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    • pp.141-148
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    • 2016
  • The long-span bridges such as Incheon Bridge and Seohae Grand Bridge are located on the coastal region effected frequently by strong wind of typhoons. In order to ensure the wind-resistant performance of the structure, estimation of the proper design wind speed is very important. In this study, stochastic estimation of design wind speed incurred by typhoons is carried out. For this purpose, we first established probability distribution of climatological parameters such as central pressure depth, distance of closest approach, translation speed and heading to build statistical model of typhoons, which are employed in Monte Carlo simulation for hypothetical typhoons. Once a typhoon is generated with statistically justified parameters, wind speeds are estimated along its path using wind field model. Thousands of typhoons are generated and their peak wind speeds are utilized to establish the extreme wind speeds for different return period. The results are compared with design basic wind speeds in Korean Highway Bridge Design Code, showing that the present results agree well with similar studies while the existing code suggests higher design wind speed.

A Study on the Community of Wintering Waterbirds Gangjin Bay (강진만에 월동하는 수조류 군집에 관한 연구)

  • Kim In-Kyu;Lee Han-Soo;Pack Woon-Kee;Lee Joon-Woo;Choi Young-Bok
    • Korean Journal of Environment and Ecology
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    • v.19 no.3
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    • pp.305-311
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    • 2005
  • For research of the wintering waterbirds we surveyed monthly from October 2000 to March 2001 on Gangjin Bay, Chollanam-do, Korea. During the study period, the waterbirds were observed 9,825 individuals and 36 species. The highest dominant species was Anaspiatyrhynchos which occupied the $48.42\%$, the one followings were Anas crecca $(10.8\%)$, Tadorna tadorna $(9.7\%)$, Anas poecilorhyncha $(9.5\%)$ and Cygnus cygnus $(4.8\%)$. A regularly observed species in every months were 3 species, Egretta garzetta, Anas pin tyrhynchos and Anas poecilorhyncha. The Cygnus cygnus of specially protected species was observed the 232 individuals maximumly in November and the 125 individuals to a minimum in December. The index of species diversity was minimum 1.24 at October and maximum 2.01 at March. This area has provided a suitable roosting and feeding place for waterbirds. The peak count of the wintering whooper swan was 232 individuals in Gangjin Bay. Therefore, We need the conservation and management of Gangjiun Bay.

Threshold-dependent Occupancy Control Schemes for 3GPP's ARQ (3GPP의 ARQ를 위한 threshold에 의존하는 점유량 조절 방식)

  • Shin, Woo-Cheol;Park, Jin-Kyung;Ha, Jun;Choi, Cheon-Won
    • Journal of IKEEE
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    • v.9 no.2 s.17
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    • pp.123-135
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    • 2005
  • 3GPP RLC protocol specification adopted a window-controlled selective-repeat ARQ scheme for provisioning reliable data transmission. Inevitably, the re-ordering issue arises in the 3GPP's ARQ since it belongs to the selective-repeat ARQ clan. A long re-ordering time results in the degradation of throughput and delay performance, and may invoke the overflow of the re-ordering buffer. Also, the re-ordering time must be regulated to meet the requirements of some services which are both loss-sensitive and delay-sensitive. In the 3GPP's ARQ, we may deflate the occupancy of the re-ordering buffer by reducing the window size and/or length of the status report period. Such a decrease, however, deteriorates the throughput and delay performance and encroaches the resource of the reverse channel. Aiming at reducing the occupancy at the re-ordering buffer while suppressing the degradation of throughput and delay performance, we propose threshold-dependent occupancy control schemes, identified as post-threshold and pre-threshold schemes, as supplements to the 3GPP's ARQ. For judging the effectiveness of the proposed schemes, we investigate peak occupancy, maximum throughput and average delay in the practical environment involving fading channels. From the simulation results, we observe that the proposed schemes invoke the performance trade-off between occupancy and throughput in general. Also, we reveal that the post-threshold scheme is able to improve the throughput and delay performance of the ordinary 3GPP's ARQ without inflating the occupancy of the re-ordering buffer.

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Fecundity and Hatchability of Natural Stone Flounder Kareius bicoloratus from the West Coast of Korea (서해 자연산 돌가자미, Kareius bicoloratus의 포란수와 부화율)

  • Jun, Je-Cheon;Kang, Hee-Woong;Kim, Byung-Gyun;Choi, Ki-Ho;Jo, Ki-Che
    • Korean Journal of Ichthyology
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    • v.21 no.4
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    • pp.239-246
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    • 2009
  • To establish a database for artificial seed production of stone flounder Kareius bicoloratus, experiments were conducted to study the characteristics of spawning and fecundity of this species. Broodstocks were captured in the area of Gyeokryeolbiyeoldo, Chungnam, Korea in October 2003 and induced to natural spawning. The broodstock consisted of 12 females (34.5~51.0 cm total length and 540~2,200 g body weight) and 23 males (29.0~38.0 cm total length and 310~680 g body weight). Gonad development began in December and proceeded in the direction of the tail; measurements were made with the naked eye. The tank-held broodstock were reared for 3 months before spawning, which continued for 77 days from January 9 to March 27, 2004. Daylength during the spawning was recorded at the yearly shortest of 9.8~12.1 hours and the water temperature was maintained at $8.4{\sim}12.2^{\circ}C$. The total fecundity was 19,844,000 individuals, among which 15,433,000 individuals (77.8%) were produced during the mid-spawning period. The average bloating rate, egg-fertilization rate and hatching rate of the total number spawned reached 50.4%, 58.5% and 55.6%, respectively, and 93.8% of the hatched fry appeared normal. The number of total eggs in absolute fecundity per total length was proportional to both lengths, as was the number of total eggs in relative fecundity per total length. The number of total eggs in absolute fecundity per body weight was proportional to body weight as was the number in relative fecundity per body weight except that the number in relative fecundity per gram decreased after a peak in increased body weight at a certain point.

The Interrelationship between Pop Art and Textile Design (팝 아트와 텍스타일 디자인의 상호관계)

  • 차임선
    • Archives of design research
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    • v.13
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    • pp.177-200
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    • 1996
  • The purpose of this study is to show the textile designers how to be creative and how to accept other ideas which are not necessarily of their own, and to show what exactly creating anything means. During the 1950's and'60s. America and Europe reached their peak in developing their consumption culture. After World War II, America achieved an astonished feat in developing its thechnology and industry to cause the economy to a rapid ascendence. The U.S. government adopted the Keynsian theory in its economic policy. The Keynsian theory advocates the consumer spending. And during this time period the American public developed consumption habit. Mass production and mass media went in hand to induce the public to buy. The public became an important target for the advertising stratages of the industry. In order for the industry to advertise the mass produced products, it had to utilize the mass media such as television, newspaper, and magazine. And mass media came into play an important role not to advertise the products, but to imform and educate the public about the products. This corporate stratege is further enhanced by the desire of the American public to climb up the ladder by way of material possession. Pop Art was born not only in reflecting the ideology of the consumption culture, but acted as a catalyst for more spending. The subjects of Pop Art are cars, foods, comics, Hollywood actors and movie scenes, the famous singers or persons. Andy Warhol specifically used the chosen image repeatedly to emphasize the redundacy of the image. The common factors which exist between Andy Warhol's Pop Art and textile design is the repetition in form, and the way of transferring an image to a canvas - Warhol used the frotttage technique to transfer an image to a canvas and textile design is transferred to a paper by way of transferring technique. Also the way Warhol thought of his paintings as a decorative elements and made a couple of his paintings into wallpapers or exhibits his painstings wall to wall demonstrates his close alliance with the textile design, let alone his comercial design background. In this study, I examined the inter-relationship between textile design and Pop Art. To carry out this study, I examined the comsumption culture: and the biomorphic relationship of culture and art: and Pop art and its transience stage. The major finding of this study is there exists a common denomenator between textile design and Pop Art, especially of Andy Warhol's.

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The Clarification Of Spatial-temporal Patterns of Phytoplankton From Southern Korean Coastal Waters In 2004 (2004년 한국 남해연안 해역에 출현하는 식물플랑크톤의 시.공간적 특성 조사)

  • Cho Eun-Seob;Kim Jeong-Bae;An Kyoung-Ho;Yu Jun;Kwon Jung-No;Jeong Chang-Su
    • Journal of Environmental Science International
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    • v.15 no.6
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    • pp.539-562
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    • 2006
  • The clarification of spatial-temporal patterns of phytoplankton from southern coastal waters during the period of March to November in 2004 was carried out. Total cell numbers were shown in 5,286 cells $ml^{-1}$ on March and reached to encounter a peak of 27,775 cells $ml^{-1}$ on July. Mean cell number was also shown in maximum of 1,587 cells $ml^{-1}$ on July, which recorded approximately two times higher than on June. The cell number of phytoplankton from southmiddle waters attained an abundance of ${\geq}35%$ regardless of months, which was the highest the abundance of phytoplankton in 2004 than any other waters in this study. Southwestern waters were lower the cell number of 2-5 times than those of southmiddle and southeastern waters. In particular, Prorocentrum occurred in southeastern waters on June and the highest cell number of 8,200 cells $ml^{-1}$ around Tongyeong region on July, which was recorded to occupy the value of 60.9% in southeast waters. The abundance of Skeletonema costatum as a dominant taxa in southwest was shown in ${\geq}60%$ on March, July, September, and October, whereas was also recorded to achieve the abundance of above 80% in southmiddle waters on March, July, and September. The majority of the taxa in southeastern waters was diatom: Eucampia zoodiacus, and Chaetoceros spp.. They occupied above 45%. On November, most of southern waters were abundant to Chaetoceros spp. On the basis of cluster analysis using SPSS ver 10.0, phytoplankton occurring on March showed somewhat no correlation with all of southern waters. In contrast to on March, the relationship between southwestern and southmiddle waters was shown on August and November, indicating a distinction from southeastern waters. However, the distance between southwestern/middle and southeastern waters appeared to be less than 5. Consequently, the abundance of phytoplankton in southern waters showed much fluctuations in temporal and spatial assays. In particular, southwestern and southmiddle waters during the periods of summer and winter appeared to be a similar to environmental characteristics.