• 대한두개안면성형외과학회지
• /
• 제25권3호
• /
• pp.145-149
• /
• 2024

The superficial temporal artery (STA) bifurcates into frontal and parietal branches. The parietal branch is used as a recipient vessel for scalp reconstruction, but it is absent in approximately 16.3% of individuals. In this case, a 72-year-old woman with an occipital scalp defect lacked both the parietal branch of the STA and the superficial temporal vein. To address this anatomic variation, we used the frontal branch of the STA and the posterior auricular vein as alternative recipient vessels for anterolateral thigh free flap reconstruction. The surgical procedure involved end-to-end microvascular anastomosis of one artery and one vein. Partial flap necrosis occurred postoperatively, but eventually resolved with debridement. The frontal branch of the STA and the posterior auricular vein can serve as reliable alternatives in the absence of the parietal branch. Reconstructive surgeons should be aware of anatomic variations of the STA and adapt their surgical approach accordingly.

• 한국지하수토양환경학회:학술대회논문집
• /
• 한국지하수토양환경학회 2006년도 총회 및 춘계학술발표회
• /
• pp.282-285
• /
• 2006

This study is to present the method for estimating groundwater recharge with temporal-spatial variability using the SWAT model which can represent the heterogeneity of the watershed. The SWAT model can simulate daily surface runoff, evapotranspiration, soil storage, recharge, and groundwater flow within the watershed. The model was applied to Musimcheon watershed located in the upstream of Mihocheon watershed. Hydrological components were determined for the period 2001 - 2004, and the validity of the results was tested by comparing the estimated runoff with the observed runoff data at the outlet of the catchment. The results of temporal and spatial variations of recharge were presented, This study suggests that variations in recharge can be significantly affected by subbasin slope as well as land use changes.

• 대한원격탐사학회지
• /
• 제37권4호
• /
• pp.789-802
• /
• 2021

Synthetic Aperture Radar (SAR) at C-band is an ideal remote sensing system for crop monitoring owing to its short wavelength, which interacts with the upper parts of the crop canopy. This study evaluated the potential of dual polarimetric Sentinel-1 at C-band for monitoring rice phenology. Rice phenological variations occur in a short period. Hence, the short revisit time of Sentinel-1 SAR system can facilitate the tracking of short-term temporal morphological variations in rice crop growth. The sensitivity of SAR backscattering coefficients, backscattering ratio, and polarimetric decomposition parameters on rice phenological stages were investigated through a time-series analysis of 33 Sentinel-1 Single Look Complex images collected from 10th April to 25th October 2020 in Gimhae, South Korea. Based on the observed temporal variations in SAR parameters, we could identify and distinguish the phenological stages of the Gimhae rice growth cycle. The backscattering coefficient in VH polarisation and polarimetric decomposition parameters showed high sensitivity to rice growth. However, amongst SAR parameters estimated in this study, the VH backscattering coefficient realistically identifies all phenological stages, and its temporal variation patterns are preserved in both Sentinel-1A (S1A) and Sentinel-1B (S1B). Polarimetric decomposition parameters exhibited some offsets in successive acquisitions from S1A and S1B. Further studies with data collected from various incidence angles are crucial to determine the impact of different incidence angles on polarimetric decomposition parameters in rice paddy fields.

• Journal of Positioning, Navigation, and Timing
• /
• 제2권2호
• /
• pp.109-114
• /
• 2013

The vulnerability of GPS to interference signals was reported in the early 2000s, and an eLORAN system has been suggested as a backup navigation system for replacing the existing GPS. Thus, relevant studies have been carried out in the United States, Europe, Korea, etc., and especially, in Korea, the research and development is being conducted for the FOC of the eLORAN system by 2018. The required performance of the eLORAN system is to meet the HEA performance, and to achieve this, it is essential to perform ASF correction based on a dLORAN system. ASF can be divided into temporal ASF, nominal ASF, and spatial ASF. Spatial ASF is the variation due to spatial characteristics, and is stored in an eLORAN receiver in the form of a premeasured map. Temporal ASF is the variations due to temporal characteristics, and are transmitted from a dLORAN site to a receiver via LDC. Unlike nominal ASF that is obtained by long-term measurement (over 1 year), temporal ASF changes in a short period of time, and ideally, real-time correction needs to be performed. However, it is difficult to perform real-time correction due to the limit of the transmission rate of the LDC for transmitting correction values. In this paper, to determine temporal ASF correction frequency that shows satisfactory performance within the range of the limit of data transmission rates, relative variations of temporal ASF in summer and winter were measured, and the stability of correction values was analyzed using the average of temporal ASF for a certain period.

• 한국대기환경학회지
• /
• 제19권2호
• /
• pp.191-204
• /
• 2003

A one dimensional time dependent acid rain model considering size distribution of aerosols and hydrometeors is developed to predict observed chemical and physical properties of precipitation. Temporal variations of anions and cations observed are predicted fairly well with acid rain model simulations. It is found that aerosol depletion rates are highly dependent on aerosol sizes under the assumption of Marshall - Palmer raindrop size distribution. Also, the aerosol depletion during the initial rain event largely influences on ion concentrations in rainwaters.

• 한국대기환경학회지
• /
• 제18권4호
• /
• pp.253-264
• /
• 2002

Surface ozone concentrations measured at 40 monitoring sites in three major cities (Seoul, Busan, and Daegu) of Korea during 1993~2000 were analyzed to understand the characteristics of temporal and spatial distributions. Trends were analyzed for annual mean, 95th percentiles of daily 8-hour maximum and days exceeding 8-h ozone standard of 60 ppb. Three indicators exhibited increasing trends (+0.75 ppb yr$^{-1}$ , +2.20 ppb yr$_{-1}$ , and +5.35 days yr$_{-1}$ on average) throughout the study period at all cities. Diurnal and seasonal variations were the largest in Seoul followed by Daegue and Busan, due to the high photochemical production and titration of ozone (Seoul), strong wind and constant supply of background ozone from the ocean (Busan). In the urban centers and industrial areas at all cities, scavenging of ozone by NO reduces the daily 8-hour maximum ozone by 10 ppb on average. High concentrations of ozone have frequently occurred in downwind eastern (Seoul and Daegu) or northern (Busan) sides of the territory. In particular, the coastal area of Busan had relatively high ozone level due to the local sea land breeze circulation. The results indicated that the temporal and spatial variations of ozone concentration were non -uniform and were closely related to the local environments; emission levels, climates, and geographic locations.

• 수산해양교육연구
• /
• 제25권5호
• /
• pp.1046-1054
• /
• 2013

Spatial and temporal variations of sea surface temperature (SST), abundances of copepods, euphausiids, amphipods, and chaetognaths were investigated in the western waters of the Korean Peninsula. Zooplankton and SST were monitored at 63 stations arrayed in six transects ($124^{\circ}00^{\prime}-126^{\circ}30^{\prime}E$, $34^{\circ}00^{\prime}-37^{\circ}00^{\prime}N$) in February, April, June, August, October, and December during 1978-2010. In general, SST increased $0.7-3.8^{\circ}C$ during the last three decades with spatio-temporal variations. SST was lowest in February and highest in August. SST was highest in the northernmost transect and declined gradually along transects to the south. The general pattern of interannual variations of SST was similar to the global pattern, which has been increasing. Trends of abundances of all zooplankton groups slightly increased interannually and peaked seasonally in June and August, except chaetognaths, which fluctuated around the long-term mean value with a seasonal peak in August and October. Abundances of zooplankton groups were highest in the northernmost transect while those of euphausiids were highest in the southern transect. We discuss the distribution patterns of SST and zooplankton groups in relation to oceanographic characteristics in the study area.

• 한국환경과학회지
• /
• 제29권11호
• /
• pp.1141-1151
• /
• 2020

The impact of sound speed variability in the sea is the very important on acoustic propagation for the underwater acoustic systems. Understanding of the temporal and spatial variability of ocean sound speed in the sea around the Ieodo were obtained using oceanographic data (temperature, salinity). from the Korea Oceanographic Data Center, collected by season for 17 years. The vertical distributions of sound speed are mainly related to seasonal variations and various current such as Chinese coastal water, Yellow Sea Cold Water (YSCW), Kuroshio source water. The standard deviations show that great variations of sound speed exist in the upper layer and observation station between 16 and 18. In order to quantitatively explain the reason for sound speed variations, Empirical Orthogonal Function (EOF) analysis was performed on sound speed data at the Line 316 covering 68 cruises between 2002 and 2018. Three main modes of EOFs respectively revealed 55, 29, and 5% the total variance of sound speed. The first mode of the EOFs was associated with influence of surface heating. The second EOFs pattern shows that contributions of YSCW and surface heating. The first and second modes had seasonal and inter-annul variations.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2006년도 제37회 하계학술대회 논문집 D
• /
• pp.2113-2115
• /
• 2006

This paper proposes a spatio-temporal correlation algorithm that takes advantage of the spatial and temporal correlations in video streams for error concealment. The spatio-temporal correlation algorithm sets the neighborhood area of the damaged part as a reference window, then finds the area that best matches the reference window in the previous frame. The best-matched area in the previous frame replaces the damaged part in the current frame. The results of ten variations of the proposed algorithm are compared with conventional error concealment methods. These methods include the ones applicable to P-frames as well as I-frames. The comparison results show that the proposed algorithm is very efficient for l-frame error concealment with a large motion between frames.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• 제28권1호
• /
• pp.69-73
• /
• 2002

Temporal muscle flap is usefull for the reconstruction of tissue defect at the oral and maxillofacial area. This article reports 3 cases of temporal muscle flap for the soft tissue reconstruction of infraorbital, palatal and mandibular retromolar area after tumor ablation. The advantages and disadvantage, postoperative complications and technical variations were reviewed and our 3 cases were evaluated in this aspects.