• 한국방송∙미디어공학회:학술대회논문집
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• 한국방송∙미디어공학회 2018년도 추계학술대회
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• pp.114-116
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• 2018

본 논문에서는 빔-호핑 위성 전송 시스템을 위한 카운터를 기반의 연속적인 beam allocation time schedule (BATS) 변경 기법을 제안한다. 제안하는 기법은 BATS 를 처음 변경할 때, 카운터를 기반으로 gateway (GW)와 space craft (SC) 양단에서 BATS 변경 시점을 동기화 시킨다. 이 후, BATS를 계속 변경하더라도 전송 데이터 손실 없이 BATS 를 변경할 수 있다.

• 한국동물학회지
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• 제20권2호
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• pp.67-76
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• 1977

The periodic changes of testis and \ulcorner션 epididymidis in Korean hibernating bats, the oriental discoloured bats (Vesportilio superans Thomas) and the Korean greater horseshoe bats (Rhinolophus ferrumequinum korak Kuroda) were studied in order to clarify the possibility of correlation between their histological findings and one of physiological facets, hibernation, and the results obtained were as follows: 1. The spermatogenic function of the oriental discoloured bats obtained in July and August was depressed although the spermatocytes showed a considerable cell proliferation. Few mature sperms were observed in the seminiferous tubules of the bat obtained in August. 2. The spermatogenic function of the Korean greater horeshoe bats obtained in September was not remalkable but a considerable number of sperms were stored in the excretory ducts which were characterized by existence of para-tubular spaces in the ductus epididymidis. 3. The spermatogenic epithelia of the Korean greater horseshoe bats obtained in December showed histologically atrophied figures. However, a vast number of sperm remained in extremely expaned luminae of the ductuc epididymidis which epithelial cells were maintained rectangular in shape. 4. These results suggest that there are periodic changes of the spermatogenic epithelia and the excretory ducts, and that those histological changes are closely related to their wintering.

• 한국환경과학회지
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• 제26권7호
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• pp.817-826
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• 2017

We analyzed how foraging area use changed in female Pipistrellus abramus during the breeding season. Radio tracking was used to follow 12 female P. abramus in Gyeongju City, from 2013 to 2015. We followed three bats in each of four stages of reproduction: early pregnancy, late pregnancy, lactation, and post-lactation. Our data showed that the usable area of a foraging site and the area that was actually used by bats in that site were different, and foraging site use also differed according to stage of reproduction. The bats used arable land the most, with use rates of 57%, 40.4%, and 73.2% during early pregnancy, late pregnancy, and lactation, respectively. Bats in a post-lactation state did not use arable areas at all and instead foraged over bodies of water 90% of the time. There was no difference in the use of each foraging environment between bats in early pregnancy and late pregnancy. However, bats in late pregnancy and those that were lactating did use arable land to different extents, and bats that were lactating and those that were post-lactation also used arable land and bodies of water to different extents.

• 한국환경과학회지
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• 제32권10호
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• pp.685-692
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• 2023

This study was conducted in organic and conventional farming areas to understand the activity and habitat use patterns of bats according to farming methods. A total of 521 bat sounds were recorded, of which approximately 90% sounds were of Pipistrellus abramus. The activity of bats according to farming methods was significantly higher in organic farming areas. Bat activity was the highest for approximately an hour after sunset, and gradually decreased. Buzz calls in bats were also significantly higher in organic farming areas, and buzz calls were identified only in Pipistrellus abramus. Our results suggest that the activity of bats was significantly higher in organic farming areas, and the differences in activity and habitat use of bats according to farming methods show that bats can be used as an indicator species of farming methods.

• 대한바이러스학회지
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• 제26권1호
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• pp.91-99
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• 1996

To understand whether the bats inhabiting in Korea play role as hosts harboring Hantavirus that cause acute febrile diseases, a total number of 802 bats of 9 species were collected from seven provinces in Korea from 1989 to 1995 and tested for the presence of antibodies to Hantavirus by means of immunofluorescent antibody (IFA) technique. The results are summarized as follow. 1. Total 802 captured bats were classified into 9 different species with the following distribution. They were Rhinolophus ferrumequinum, Eptesicus serotinus, Miniopterus sehreibersii, Vespertilio superans, Myotis mystatinus, Murina leucogaster, Myotis formosus, Myotis macrodactylus and Plecotus auritus with numbers and rates of 423 (52.74%), 291 (36.28%), 47 (5.86%), 28 (3.49%), 8 (1.00%), 1 (0.12%) and 1 (0.12%), respectively. The predominant species of the bats was Rhinolophus ferrumequinum with 52.74% of the captured. 2. Among 9 species of bats, species of Rhinolophus ferrumequinum and Eptesicus serotinus were positive with Hantavirus antibody of strain numbers 76-118. The rate of antibody positive was 3.78%. 3. The seasonal differences of Hantavirus antibody in 802 bats tested were 5.83%, 4.17%, 3.67% and 0.64% in winter, spring, summer and autumn, respectively. Again the highest viral antibody prevalence was detected in winter. It could be concluded through the study that certain species of bats inhabiting in Korea play a definite role as the host animals of certain species of Hantavirus.

• Journal of Ecology and Environment
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• 제32권3호
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• pp.191-195
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• 2009

We monitored 38 hibernation sites of Myotis formosus in South Korea and recorded the number of bats occupying each site and assessed the micro-climate at the sites during four winters from 2005 to 2009 at. The mean rock temperature of the bat roosting sites was $13.2{\pm}1.4^{\circ}C$ and the mean body temperature of the hibernating bats was $13.3{\pm}1.3^{\circ}C$. The number of hibernating bats was negatively related to the size of the entrance and positively related to the minimum ambient temperature and humidity in the site interior. More bats hibernated in roosts with smaller entrances and higher minimum ambient temperatures, and more bats selected sites presenting a narrow temperature range. This study showed that the internal environments of hibernacula of M. formosus were highly stable despite dramatic variation in the external environment.

• 한국환경과학회지
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• 제23권12호
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• pp.2083-2087
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• 2014

Between May and September 2014, a total of 226 serotine bats (Eptesicus serotinus) were captured and subsequently released at a site 50 km distant from the site of capture, in order to determine the homing ability of the bats and changes in the homing rate according to the season. The bats were captured from a nursery colony at a bridge in An-dong (Gyeongbuk, Korea), and then released at a similar site in Yeong-Ju (Gyeongbuk, Korea). We found that 115 of the 226 bats released (51%) returned to the capture site. However, there was a difference in the homing ability of the serotine bats depending on the season and reproductive status. We found that the homing rate was the highest in June during late pregnancy and the lowest in August after the lactation period.

• Journal of Ecology and Environment
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• 제43권1호
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• pp.1-8
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• 2019

Background: Hibernating bats exhibit ubiquitous winter activity in temperate zones, but there is considerable between- and within-species variety in their intensity and purpose. Bats may fly during winter for sustenance or travel to other hibernacula. This study compared inter-regional variation in the winter activity of the greater horseshoe bat (Rhinolophus ferrumequinum). We predicted that weather and hibernacula-environmental conditions would influence winter activity patterns. Results: Winter activity patterns differed between regions. In the Anseong area, we confirmed movement inside the hibernaculum, but in Hampyeong, we observed movement both inside and between hibernacula. The two regions differ by $4^{\circ}C$ in average winter temperatures. Anseong experiences 22 days during which average daily temperatures exceeded $5^{\circ}C$, whereas Hampyeong experienced 50 such days. During the hibernating period, bat body weight decreased by approximately 17-20% in both regions. Conclusions: Ambient temperatures and winter-roost environments appear to be behind regional differences in hibernating bat activity. As winter temperatures in Korea do not favor insect activity, feeding probability is low for bats. However, bats may need to access water. At Anseong, underground water flows inside the hibernaculum when the reservoir outside is frozen. At Hampyeong, the hibernaculum does not contain a water source, but the reservoir outside does not freeze during winter. In conclusion, water-source location is the most likely explanation for regional variation in the winter activity of hibernating bats.

• 생태와환경
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• 제49권4호
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• pp.385-392
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• 2016

지리적 격리는 생태학적 특징의 차이를 유발한다. 지리적인 격리는 박쥐 종 내의 소리 차이의 원인으로 알려져 왔다. 본 연구는 관박쥐의 반향정위가 지리적 차이에 의해 차이가 있는지를 알기 위해 우리나라 섬(제주도)과 내륙에서 수행되었다 우리는 내륙과 섬(제주도)에서 관박쥐가 활동기간에 휴식처로 이용하는 것으로 알려진 폐광과 동굴을 연구 지역으로 선정하였다. 관박쥐의 Hand-held call과 Free-flying call을 녹음하였다. 녹음된 펄스(pulse)는 관박쥐의 Hand-held call과 Free-flying call을 녹음하였다. 분석 결과, 내륙에서 서식하는 관박쥐의 PF는 평균 69 kHz로 섬(제주도)에 서식하는 관박쥐의 PF (71 kHz)와 차이가 났다. 판별 분석 결과에서도 내륙과 섬의 반향정위는 차이를 보였다. 우리나라 관박쥐 개체군의 PF는 유럽(82 kHz)보다는 낮고, 일본(65 kHz)보다는 높았다.

• Journal of Forest and Environmental Science
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• 제32권4호
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• pp.377-383
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• 2016

We obtained a total of 36 GPS coordinates of the seven bat species of Rhinolophus ferrumequinum, Myotis ikonnikovi, M. nattereri, M. petax, Murina ussuriensis, Plecotus auritus, and Pipistrellus abramus. Characteristics of forests (forest type, age class, DBH class and crown density), terrain (aspect, slope and distance from mountain stream) and disturbance factors (distance from human residential areas and distance from cultivated areas) that bats have used as their habitats were revealed from the GIS analysis based on GPS coordinates of the 36 positions that bats were found. The bats-preferred forest type is broad-leaf forests (43%) with the trees of the 2th (31%) and 5th (31%) age class, the trees of sapling (36%) and large DBH class (31%), and sparse crown density (67%). Bats prefer the slop direction of the east (39%), the gradient below $15^{\circ}$ (61%), the ranges within 200 m from the mountain streams (92%), the ranges within 200 m near roads (89%), the ranges of 200-400 m from human residential areas (28%), and the ranges within 200 m from cultivated areas (36%).