• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2018.11a
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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.

• The Korean Journal of Zoology
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• v.20 no.2
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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.

• Journal of Environmental Science International
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• v.26 no.7
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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.

• Journal of Environmental Science International
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• v.32 no.10
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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.

• The Journal of Korean Society of Virology
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• v.26 no.1
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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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• v.32 no.3
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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.

• Journal of Environmental Science International
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• v.23 no.12
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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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• v.43 no.1
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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.

• Korean Journal of Ecology and Environment
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• v.49 no.4
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• pp.385-392
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• 2016

Geographical isolation may lead to the populations having different ecological characteristics. Geographic isolation have been known to cause echolocation call differences in bats. In order to look at geographic differences of echolocation calls of Great Horseshoe Bats (Rhinolophus ferrumequinum), populations of inland and Jeju island habitats were examined in Korea. The study areas were some abandoned mines in the inland and caves of Jeju island, which were known as rest sites of Great Horseshoe Bats during the active season. Recording was done in two ways: Hand-held, Free-flying. Recording pulse was analyzed into five parameters: Maximum Frequency (FMAX), Minimum Frequency (FMIN), Peak Frequency (PF), Duration (D), Inter pulse Interval (IPI). Interestingly, The present study shows that the difference in echolocation between the inland and island populations. The PF of bats inhabited inland was 69 kHz. but, the PF of bats inhabited island (Jeju) was 71 kHz. There was a difference between regions. Discriminant analyses also showed clear difference between the inland and the island populations. Especially, PF of Korea population is lower than that of Europe (82 kHz) and higher than that of Japan (65 kHz).

• Journal of Forest and Environmental Science
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• v.32 no.4
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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%).