• 제목/요약/키워드: Regional variations

검색결과 357건 처리시간 0.026초

지역 파랑 예측시스템과 해양기상 부이의 파랑 특성 비교 연구 (Research on Wind Waves Characteristics by Comparison of Regional Wind Wave Prediction System and Ocean Buoy Data)

  • 유승협;박종숙
    • 한국해양공학회지
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    • 제24권6호
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    • pp.7-15
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    • 2010
  • Analyses of wind wave characteristics near the Korean marginal seas were performed in 2008 and 2009 by comparisons of an operational wind wave forecast model and ocean buoy data. In order to evaluate the model performance, its results were compared with the observed data from an ocean buoy. The model used in this study was very good at predicting the characteristics of wind waves near the Korean Peninsula, with correlation coefficients between the model and observations of over 0.8. The averaged Root Mean Square Error (RMSE) for 48 hrs of forecasting between the modeled and observed waves and storm surges/tide were 0.540 m and 0.609 m in 2008 and 2009, respectively. In the spatial and seasonal analysis of wind waves, long waves were found in July and September at the southern coast of Korea in 2008, while in 2009 long waves were found in the winter season at the eastern coast of Korea. Simulated significant wave heights showed evident variations caused by Typhoons in the summer season. When Typhoons Kalmaegi and Morakot in 2008 and 2009 approached to Korean Peninsula, the accuracy of the model predictions was good compared to the annual mean value.

Ionospheric TEC Monitoring over Jeju Island using the Chinese BeiDou Satellite Navigation System

  • Choi, Byung-Kyu;Lee, Woo Kyoung;Sohn, Dong-Hyo;Yoo, Sung-Moon;Roh, Kyoung-Min;Joo, Jung-Min;Heo, Moon Beom
    • Journal of Positioning, Navigation, and Timing
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    • 제9권1호
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    • pp.1-6
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    • 2020
  • The Chinese BeiDou Satellite Navigation System consists of three kinds of constellations: the geostationary Earth orbit (GEO), the inclined geosynchronous satellite orbit (IGSO), and the medium Earth orbit (MEO). The BeiDou has expanded its service coverage from regional to global. Recently, the BeiDou has been widely used in ionospheric total electron content (TEC) research. In this study, we analyzed the BeiDou signals for ionospheric TEC monitoring over Jeju Island in South Korea. The BeiDou GEO TEC showed a clear pattern of diurnal variations. In addition, we compared the TEC values from the BeiDou GEO, the BeiDou IGSO, GPS, and International GNSS Service (IGS) Global Ionosphere Maps (GIM). There was a difference of about 5 TEC units between the BeiDou GEO and the IGS GIM. This may be due to the altitude difference between the different navigation satellites.

층상구조에서 지진파 전파경로를 고려하여 수정된 경험 Green 함수를 이용한 지반운동 모사 (Site-Specific Ground Motions based on Empirical Green`s Function modified for the Path Effects in Layered Media)

  • 조남대;박창업
    • 한국지진공학회:학술대회논문집
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    • 한국지진공학회 2001년도 추계 학술발표회 논문집 Proceedings of EESK Conference-Fall 2001
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    • pp.19-27
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    • 2001
  • Seismic parameters fur computation of ground motions in Southern Korea are obtained from recently recorded data, and site-independent regional and site-dependent local strong ground motions are predicted using efficient computational techniques. For the computation of ground motions, we devised an efficient procedure to compute site-independent $x_{q}$ and dependent $x_{s}$ values separately. The first step of this procedure is to use the coda normalization method far computation of site independent Q or corresponding $x_{q}$ value. The next step is the computation of $x_{s}$, values fur each site separately using the given $x_{q}$ value. For computation of ground motions the empirical Green's function (EGF) is modified to account fur the depth and distance variations of subevents on a finite fault plane using the theoritical Green's function. It is computed using wavenumber integration technique in layered media. The site dependent ground motions at seismic stations in southeastern local area were properly simulated using the modified empirical Green's function method in layered medium. The proposed method and procedures fur estimation of site dependent seismic parameters and ground motions could be efficiently used in the low and moderate seismicity regions.ons.s.ons.

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Regional Variations in Spectra of (25143) Itokawa taken with Hayabusa/AMICA

  • Jin, Sunho;Ishiguro, Masateru
    • 천문학회보
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    • 제43권1호
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    • pp.73.2-73.2
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    • 2018
  • The Hayabusa remote-sensing images of near-Earth asteroid (25143) Itokawa exhibited large diversity in spectral properties. The evidence suggests a various degrees of space weathering on the surface. It is known that the space weathering changes the spectra of S-type asteroids redder and reduces the depths of absorption around $1{\mu}m$. It is therefore possible to determine the surface ages through the investigation of the degree of space weathering. It is, however, reported that the scattered light components severely degrade the Asteroid Multiband Imaging Camera (AMICA) images, especially at the wavelengths > $0.86{\mu}m$. Our team came up with a technique for subtracting the scattered light components (Ishiguro 2014). Here, we upgraded the techniqu e by applying simplex algorism to correct the artifacts for all AMICA bands. This new technique enables to apply for the longest channel (i.e., zs-band at $1.01{\mu}m$) images, which was not studied so far. With the AMICA all bands data, we estimated the surface ages at the different location to be 0.6-2 Myr. Based on this data together with the geological information (e.g. gravitational potentials and local). we will discuss about the evolution of surface materials on the asteroid.

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두경부 MRS검사의 SVS와 3D CSI 데이터의 비교 분석및 임상응용을 위한 연구 (A Comparison of MRS Data for SVS and 3D CSI in Human Brain Study)

  • 윤성익;최보영
    • 한국의학물리학회:학술대회논문집
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    • 한국의학물리학회 2005년도 제30회 춘계학술대회
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    • pp.93-95
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    • 2005
  • 자기공명분광법은 극소의 체적내애서 핵자기공명에 의하여 생화학적 성질들을 고유한 주파수에 따라서 대사물질의 신호를 얻는다. 핵자기공명의 신호는 경사자장 혹은 주파수의 크기를 조절하여 체내의 조직성분을 충분히 포함하여 통과시킨다. 획득되어진 원래 데이터는 TE, TR 등의 물리적 상수값의 변화에 의해서 영향을 받는다. 최근의 펄스 시퀀스는 고해상도 3D CSI 및 SVS가 국소적인 체적내의 대사물질의 변화량을 정성적으로 감지하므로 임상데이터로 활용하기 위한 연구가 더욱 절실하다.

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Implications of Temperature and Humidity on Pupation Patterns in the Silkworm, Bombyx mori L.

  • Lakshminarayana, P.;Naik, S.Sankar;Reddy, N.Sivarami
    • International Journal of Industrial Entomology and Biomaterials
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    • 제5권1호
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    • pp.67-71
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    • 2002
  • The implications of temperature (25,30 and 35$^{\circ}C$) and relative humidity (60, 70 and 80%) on the pupation patterns were studied in the silkworm, Bombyx mori L. Larvae of two pure silkworm breeds, Pure Mysore (PM) and NB4D2 and their hybrid, PM ${\times}4 NB4D2 were reared under experimental conditions under natural day photoperiodic (LD 12: 12) condition. The three developmental marker events viz., larval ripening, pharate pupal formation and pupal formation occurred at or around the beginning of the photo-phase. The computed of mean vector (equation omitted), based on the circular statistics, also confirmed the above. However, the length of mean vector, r and the mean vector angular variance, s varied according to temperature and humidity conditions imposed; the variations being non-significant. Extreme temperature and humidity conditions, however, resulted in reduction in pupation rate (%) for PM and PM ${\times}4 NB4D2. On the other hand, in NB4D2 pupation percentage reduced below the economic level. The temperature and humidity together seems to exert synergic impact on the pupation rate at least in the silkworm Bombyx mori, L.

타 지역 환자의 서울지역 종합병원 입원이용에 관한 연구 (Utilization Patterns of Other Region Inpatients in General Hospitals Located in Seoul Area)

  • 박영희
    • 보건의료산업학회지
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    • 제5권3호
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    • pp.63-76
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    • 2011
  • The objective of this study is to analyze the utilization patterns of other region inpatients in general hospitals located in Seoul area. For the analysis, the study utilize the nationwide data on '2008 Survey of Patients' of Ministry of Health & Welfare. The statistical methodology used in the study is the logistic regression model. This study has three major findings. First, the significant affecting sociodemographic factors in selecting general hospitals located in Seoul area was sex, age, type of payment and inpatients residence region. Second, compared to other disease groups, the inpatients on both 'congenital malformation, deformity and chromosomal abnormalities' and 'neoplasm' groups are more likely to utilize general hospitals in Seoul area. Furthermore, in 'neoplasm' disease group, inpatients with 'bones and articular cartilage malignant neoplasm' are more likely to utilize general hospitals in Seoul area. Finally, hospitals with more than 1,000 beds was chief factor in selecting Seoul-based hospitals by other region inpatients. In conclusion, the study showed that other region inpatients are more likely to utilize general hospitals located in Seoul area in case of severe disease, rare case and surgical case. Therefore, central and local authority is required to monitor local hospitals on quality of the medical service as well as support them to establish specialized medical centers by providing human and physical resources.

Geographic Variation of Granulilittorina exigua (Littorinidae, Gastropoda) in Korea Based on the Mitochondrial Cytochrome b Gene Sequence

  • Song, Jun-Im;Suh, Jae-Hwa;Kim, Sook-Jung
    • Animal cells and systems
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    • 제4권3호
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    • pp.267-272
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    • 2000
  • Partial sequence of the mitochondrial cytochrome b gene was analyzed to investigate genetic variation from 10 geographic populations of Granulilittorina exigua in Korea. The sequence of 282 base pairs was determined by PCR-directed silver sequencing method. The sequences of two species within the genus Littorina reserved in NIH blast search were utilized to determine geographic variations of species referred. The levels of mtDNA sequence differences were 0.00-2.54% within populations and 0.71-4.43% between populations. There were four amino acid differences between representative species of the genera Granulilittorina and Littorina, but no differences within populations of the genus Granulilittorina. The UPGMA and the N-J trees based on Tamura-Nei genetic distance matrix were constructed, which showed that the genus Granulilittorina was divided into three groups such as eastern (even exception for Tokdo population), southern, and western regional populations. The degrees of genetic divergence within populations of each group were p=0.021, p=0.019, and p=0.018, respectively. The divergence between the eastern and southern populations was p=0.032, showing closer relationship than with the western populations (p=0.052). Based on the diverged time estimation, the eastern and southern populations of Granulilittorina exigua in Korea diverged from the western populations about 2.1 MYBP, and the eastern and southern populations diverged from each other about 1.3 MYBP.

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GIS를 활용한 용도지역 관리방안 (A Development of Use Districting Management Using GIS)

  • 이외희;최기주
    • 대한공간정보학회지
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    • 제5권1호
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    • pp.41-55
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    • 1997
  • 본고에서는 GIS를 이용한 용도지역의 개선방안이 제시되었다. 대상지역으로는 경기도의 용인시를 대상으로 용도지역 중에서 준농림지를 대상으로 하였다. 관리자중심의 사용자의 요구분석사항을 거쳐서, 데이터베이스의 설계방안과 사용자 인터페이스를 구축하는 과정을 소개하였고, 다소 시범적이어서 기능상의 한계 및 완벽한 사용자 인터페이스의 미비 등에도 불구하고 일선의 지방정부 수준의 업무에서 사용되어질 수 있는 가능성을 제시하였다. 범용GIS인 ARC/INFO와 ArcView를 중심으로 구축되어졌고 퍼스널 컴퓨터에서 의사결정 보조시스템의 형식을 띠고 있는 본 시스템은 시간요소의 결합 등이 가미되면서 전반적 계획의 작성에 있어서 효율성과 효과성을 함께 제고할 수 있는 의사결정보조도구가 될 수 있을 것으로 기대된다.

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지방거주환자의 서울지역 의료기관 이용에 영향을 미치는 요인 (Factors Associated with Utilization Patterns of Provincial Patients Discharged from General Hospitals Located in Seoul Area)

  • 홍성옥;서원식
    • 보건교육건강증진학회지
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    • 제26권4호
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    • pp.117-127
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    • 2009
  • Objectives: The primary objective of the study is to analyze the utilization patterns of provincial patients discharged from hospitals located in Seoul area. Methods: For the analysis, the study employed the nationwide data on 'Survey of Injured Patients Discharged from Hospitals' conducted by KCDC (Korea Centers for Disease Control and Prevention). The statistical methodology used in the measurement model is a logistic regression model. Results: The study has three major findings. First, compared to other disease groups, the discharged on both 'neoplasm(cancer)' and 'congenital malformation, deformity and chromosomal abnormalities' disease groups are more likely to utilize hospitals in Seoul area. Second, as for 'neoplasm(cancer)' disease group, patients with 'bones and articular cartilage' areas are more likely to utilize hospitals in Seoul area. Finally, Hospitals with more than 1,000 beds was primary factor in selecting Seoul-based hospitals by the discharged in provincial areas. Conclusion: In sum, the study showed that patients in provincial areas are more likely to utilize hospitals located in Seoul area regardless of the severity of their cases. Local authority, therefore, is required to monitor local hospitals on regular basis, as well as support them to establish specialized medical centers by providing human and physical resources.