• 천문학회보
• /
• 제40권1호
• /
• pp.60.2-60.2
• /
• 2015

Since its detection in 1980, the $8-{\mu}m$ north-polar brightening of $CH_4$ on Juptier has not moved from $180^{\circ}$ (SysIII) longitude. The $8-{\mu}m$ $CH_4$ brightening is mostly thermal and very similar to that of $13-{\mu}m$ $C_2H_2$ emissions, but the morphology of these hydrocarbon north-polar brightenings are very different from that of the $3-{\mu}m$ $H_3{^+}$ auroral oval suggesting a significantly different excitation process yet unknown heating mechanism. Recently, Kim et al. (submitted to Icarus, 2015) found that that the center of the $3-{\mu}m$ $CH_4$ northern bright spot is located at ${\sim}200^{\circ}$ (SysIII) longitude, which is ${\sim}20^{\circ}$ west from the center of the $8-{\mu}m$ north-polar bright spot, and it does not coincide with the $3-{\mu}m$ $H_3{^+}$ bright spot. They found significantly high temperatures (500 ~ 850K) from $CH_4$ rotational lines on the $3-{\mu}m$ bright spot above the $1-{\mu}bar$ pressure level, while we find cooler temperatures (<350K) over the the $8-{\mu}m$ spot. They also found that the upper states of the $3-{\mu}m$ $CH_4$ bands are mostly populated by non-thermal excitations, such as auroral particle precipitations and/or Joule heatings in contrast to the $8-{\mu}m$ thermal emission. This finding indicates that the $10-{\mu}m$ hydrocarbon brightening is confined to low altitudes below the $1-{\mu}bar$ level eliminating the long-suggested possibility of direct auroral bombardments while opening a new possibility of dynamical origin for the $10-{\mu}m$ brightening.

• 한국환경복원기술학회지
• /
• 제6권4호
• /
• pp.24-32
• /
• 2003

This study was carried out to select proper species for early stage replantation of forest road cut-slope. From one to fourteen year elapsed forest roads in Gangwon-do, sample plots were selected, and their vegetations and environmental factors were investigated. Invaded species with high frequency ordered Lespedeza cyrtobotrya, Lysimachia clethroides, Rubus crataegifolius, Patrinia villosa, Spodiopogon sibiricus, Pueraria thunbergiana, Youngia denticulata, Dactylis glomerata, Rhus chinensis, and Pinus densiflora. North cut-slope have the highest value of invaded species number and plant coverage, and so, north aspect could be best for plant invasion. According to ordination, distribution of species were influenced by elapsed year, cut-slope aspect, and cut-slope. Lespedeza bicolor, Lespedeza cyrtobotrya, Artemisia stolonifera, Miscanthus sinensis, Rubus crataegifolius, Rhus chinensis, Lindera obtusiloba, and Pinus densiflora were considered with proper species for replantation at south slope. Also, Lespedeza bicolor, Lespedeza cyrtobotrya, Arundinella hirta, Artemisia keiskeana, Astilbe chinensis var. davidii, Rubus crataegifolius, Weigela subsessilis, Stephanandra incisa, and Rhododendron mucronulatum were considered with proper species as replantation at north slope.

• 한국어류학회지
• /
• 제21권4호
• /
• pp.311-321
• /
• 2009

Three categories (freshwater, amphidromous, and marine fishes) of Taiwanese fishes are analyzed on the basis of zoogeographic elements, viz. China element, Indo-China element, Indo-West Pacific element, Indo-Pacific element, North-Pacific element, Japan-Oregon element, and circumtropical element. Freshwater fishes, which include the China and Indo-China elements, are distributed on part of the boundary area between the Palaearctic and Oriental regions of Wallace (1876). Diadromous fishes include the North-Pacific, Indo-China and Indo-West Pacific elements. Taiwanese salmon, a landlocked (initially diadromous) species that became established in Taiwan between 0.5 my B.P. and the early Pleistocene, is recognized as a distinct taxon included within the Oncorhynchus masou complex, which comprises here three species and two subspecies, viz. Oncorhynchus masou masou (Sancheoneo, Songeo, Sakura-masu or Yamame), O. masou ishikawae (Satsuki-masu or Amago), O. sp. (Biwa-masu), and O. formosanus (Taiwanese salmon), based on molecular, morphological and biological studies. Marine fishes are discussed under the following headings, brackish-water fishes (fishes of brackish waters and seas adjacent to continental coastlines, North Pacific and Indo-West Pacific elements; fishes of brackish waters and seas primarily around islands, Indo-West Pacific element), reef fishes (fishes of inshore reefs along continental coastlines from 0 to ca.100 m depth, Indo-West Pacific element; fishes of inshore reefs primarily around islands from 0 to ca.100 m depth, Indo-West Pacific element; fishes of offshore reefs along continental shelf edges from ca.150 to 300 m depth, circumtropical and Indo-Pacific elements; fishes of offshore reefs primarily around islands from ca.150 to 300 m depth, Indo-Pacific element), demersal fishes (fishes on continental shelves shallower than ca.150 m depth, Indo-West Pacific and Japan-Oregon elements; fishes on edges and upper continental slopes from ca.150 m to 500 m depth, Indo-West Pacific, Indo-Pacific, and circumtropical elements; fishes on lower continental slopes to abyssal plains from ca.500 m to 6,000 m depth, circumtropical element and rarely Indo-Pacific element), pelagic fishes (epipelagic fishes from 0 to ca.150 m depth, Indo-West Pacific, Indo-Pacific or circumtropical elements; meso- and bathypelagic fishes from ca.150 to 3,000 m depth, circumtropical element). The distribution of Taiwanese marine fishes are influenced by the Kuroshio Current, low-salinity and low-temperature waters from mainland China, and sea-bottom topography.

• 한국농림기상학회지
• /
• 제5권4호
• /
• pp.233-237
• /
• 2003

본 연구는 우리나라 중부지방의 굴참나무 천연 임분을 대상으로 입지환경별 생장 및 수분생리 특성을 파악하여 합리적인 경영방안을 제시하기 위하여 수행되었다. 연구 대상지의 굴참나무림은 평균 206.5 ㎥/ha을 나타냈으며, 각 방위별로 본수, 단면적, 재적 등의 임분 통계량을 보면 북사면에서 남사면으로 갈수록 증가하는 경향을 보이고 있지만 연년생장량과 10년간의 정기평균 생장량은 반대로 남사면에서 가장 낮은 값을 나타내고 있다. 오후 12∼14시 사이에 측정된 최대 수분포텐셜(Ψw)을 각 방위 및 고도별로 구분하여 분석한 결과 굴참나무는 북사면에서 남사면으로 가면서 수분포텐셜이 낮아지는 경향을 보였으며, 고도별 수분포텐셜은 상부에서 하부로 가면서 증가하였다. 각 방위별 토양 수분함량은 북사면에서 남사면으로 가면서 감소하는 경향을 나타냈고, 토양 수분함량에 따른 굴참나무의 수분포텐셜은 고도의 음의 상관관계를 나타냈다. 따라서 연구 대상지의 굴참나무는 남사면에서 수분 요구도가 높은데, 이는 다른 사면 보다 생육 본수가 많아 종내 경쟁이 심한 결과로 판단된다.

• Ocean and Polar Research
• /
• 제26권2호
• /
• pp.299-309
• /
• 2004

Conductivity-temperature-depth (CTD) data obtained along a meridional section in the eastern tropical Pacific in July 2003 have been analyzed to identify various water masses, and to examine the hydrographic structure and zonal geostrophic currents in the upper 1000 m. Water mass analysis shows the existence of subtropical and intermediate waters, characterized by layers of subsurface salinity maximum and minimum, originating from both hemispheres of the Pacific. Vertical section of temperature in the upper 200 m shows the typical trough-ridge structure associated with the zonal current system for most of the tropical Pacific. Water with the lowest salinity of less than 33.6 was found in the upper 30 m between $8.5^{\circ}N$ and $10.5^{\circ}N$ in a boundary zone between the North Equatorial Current and North Equatorial Countercurrent. Temporal changes in water properties observed at $10.5^{\circ}N$ over a period of 9 days suggest both the local rainfall and horizontal advection is responsible for the presence of the low-salinity water. Development of a barrier layer was also observed at $10.5^{\circ}N$. In the North Equatorial Current region a local upwelling was observed at $15^{\circ}N$, which brings high salinity and cooler subtropical water to the sea surface. A band of countercurrent occurs in the upwelling region between $13^{\circ}N$ and $15^{\circ}N$.

• Ocean and Polar Research
• /
• 제26권2호
• /
• pp.351-360
• /
• 2004

To investigate latitudinal variations in the zooplankton community along the meridian line ($5^{\circ}N-12^{\circ}N$, $131.5^{\circ}W$), we measured temperature, salinity, nitrate, chlorophyll-a and zooplankton at depths above 200 m from July $10^{th}$ to $25^{th}$, 2003. For comparative analysis, data of the physico-chemical properties and chl-a were matched to the two sampling depths (surface mixed layer and thermocline depth-200 m) of zooplankton. Latitudinal differences in the mesozooplankton distribution were mainly influenced by divergence formed at a boundary line formed by currents of opposing directions, consisting of North Equatorial Current (NEC) and North Equatorial Counter Current (NECC). High concentrations of chl-a south of $9^{\circ}N$, caused by equatorial upwelling related nutrients, is thought to be affected by the role of this divergence barrier, supported by relatively low concentrations in waters north of $9^{\circ}N$. The latitudinal differences of the chl-a were significantly associated with the major groups of zooplankton, namely calanoid and cyclopoid copepods, appendicularians, ostracods, chaetognaths, invertebrate larvae, and others. And temperature significantly affected the latitudinal variation of radiolarians, siphonophores, salps and immature copepods. The latitudinal differences in the two factors, temperature and chl-a, which explained 71.0% of the total zooplankton variation, were characterized by the equatorial upwelling as well as the divergence at $9^{\circ}N$. The physical characteristics also affected the community structure and abundance of zooplankton as well as average ratios of cyclopoid versus calanoid copepods. The abundance of dominant copepods, which were consistent with chl-a, were often associated with the carnivorous zooplankton chaetognaths, implying the relative importance of bottom-up regulation from physical properties to predatory zooplankton during the study period. These results suggested that latitudinal distribution of zooplankton is primarily controlled by current-related divergences, while biological processes are of secondary importance in the northeastern Equatorial Pacific during the study period in question.

• 한국언론정보학보
• /
• 제31권
• /
• pp.9-49
• /
• 2005

이 연구는 북한의 저널리즘 이론이 강조하는 국제정세선전과 당 대외정책간의 관계를 중심으로 북한신문의 국제뉴스가 지닌 보도형식과 내용, 그리고 정세선전의 특성을 고찰하였다. 이를 위해 북한의 대표적 일간지 ${\ulcorner}$로동신문${\lrcorner}$과 ${\ulcorner}$민주조선${\lrcorner}$의 국제정세선전 기사를 내용분석하였다. 분석결과에 따르면, 북한신문의 국제뉴스는 김정일 체제가 지향하는 최근의 대외정책 변화를 충실하게 반영하여 당 중앙이 의도하는 대로 국제관계를 분석하고 정세추이를 선전 선동함으로써 주민을 통제하고 동원하는 이데올로기 도구로 활용되고 있음을 알 수 있었다. 그러나 보도의 형식과 내용면에서 두 신문 간의 의미 있는 차이는 발견되지 않았다. 북한의 정치권력과 언론보도의 조응관계를 국제 커뮤니케이션의 관점에서 논의하였다.

• Parasites, Hosts and Diseases
• /
• 제54권4호
• /
• pp.439-446
• /
• 2016

Toxoplasmosis is a protozoan disease that is caused by Toxoplasma gondii in livestock and humans. Due to its medical and veterinary importance, it is essential to study the seroprevalence of T. gondii infection among humans and animals in various parts of the world. The major objective of this study was to determine the seroprevalence and spatial distribution of toxoplasmosis in small ruminants (sheep and goats) of north-eastern region, Pakistan. A total of 1,000 animals comprising of sheep (n=470) and goats (n=530) were examined for T. gondii infection by using ELISA. An epidemiological data was collected in the form of questionnaire. A surface has been generated by using method of interpolation in Arc GIS with the help of IDW (inverse distance weight). The results showed higher seroprevalence of T. gondii in goats (42.8%) as compared to sheep (26.2%). The seroprevalence was higher in females as compared to males in all examined ruminants. Similarly, there is a wide variation in the seroprevalence of T. gondii in different breeds of sheep and goats showing higher seroprevalence in Teddy (52.8%) and Damani breed (34.5%) of goat and sheep's, respectively. The geographical and spatial distribution of T. gondii shows that it is widely distributed in different parts of the north-eastern region of Pakistan. Our results suggest widespread environmental contamination with T. gondii oocysts and that small ruminants could be a potentially important source of T. gondii infection if their infected meat is consumed undercooked.

• 한국작물학회지
• /
• 제41권3호
• /
• pp.376-383
• /
• 1996

이제까지 보고된 앙소시대 농업유적을 검토하여 앙소시대 농업의 발전을 주로 도속혼작 농업의 분포로 파악하고 도속혼작구의 북한계선을 연장하여 도속의 동북전파를 고찰하였다. 앙소시대문화 유적을 가지고 도작농업구, 속작 농업구 그리고 도속혼작 농업구의 구분을 시도하였다. 도혼작 농업구의 도률유적을 검토하고 앙소시대 중의 도속혼작구의 변천을 검토하여 그 북한계선이 남북으로 이동했음을 고찰하였다 앙소시대 장강유역 및 황회지구에서의 고고 발굴물을 가지고 도작에 영향하였을 것으로 생각되는 기후 · 환경을 고찰하였다. 도속혼작구 북한계선의 남북이동을 가지고 도작의 동북향 전파 특히 한국 한강유역으로의 전파를 추측하였다.

• 자원환경지질
• /
• 제33권5호
• /
• pp.425-434
• /
• 2000

The 3.5 KHz seismic survey was carried out for studying the distribution pattern of the unconsolidated sediments of the Yeosu Sound on the southern coast of the Korean Peninsula. Field data originally recorded in analog are converted and processed digitally to recover the high-resolution acoustic profiles. Across the north-south trending channel with the depth of 20~30 m, different seismic facies types are observed in the top section of sediments. The western part is characterized by the continuous high-amplitude subparallel reflectors within which the acoustic turbidity as a token of the presence of gas is commonly observed, whereas the counterpart largely shows poor reflectors and has shallow acoustic basement toward the north. The dissimilarity of the seismic expression across the channel can be interpreted as the result of the change of depositional environment caused by relative sea-level fluctuations of the late-Quaternary. During the last glacial period, the Yeosu Sound was exposed and eroded by the paleo-Seomjin River. By the following rapid rise of sea level, it was covered by the transgressive sand sheet. When the sea level reached near the present position, the muddy sediment has accumulated only in the western part of the Yeosu Sound as its depositional front has moved toward the north. It is partly caused by the asymmetrical tidal current in the Yeosu Sound where the flood near the bottom has stronger current flow and contains more suspended sediments.