• Journal of Astronomy and Space Sciences
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• v.24 no.4
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• pp.269-274
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• 2007

We established a regional ionospheric model for investigating ionospheric TEC (Total Electron Contents) variations over the Korean Peninsula during major geomagnetic storms. In order to monitor the ionospheric TEC variations, we used nine permanent GPS reference stations uniformly distributed in South Korea operated by the Korea Astronomy and Space Science Institute (KASI). The cubic spline smoothing (CSS) interpolation method was used to analyze the characteristics of the ionospheric TEC variations. It has been found that variations of TEC over the Korean Peninsula increase when a major geomagnetic storm occurred on November 20, 2003. The TEC has increased about one and a half of those averaged quite days at the specific time during a geomagnetic storm. It has been indicated that the KASI GPS-derived TEC has a correlation with the geomagnetic storm indices (eq. Kp and Dst indices).

• Journal of Korean Society for Atmospheric Environment
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• v.16 no.3
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• pp.225-236
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• 2000

Diurnal variations of wind field and pollutant dispersion over the Yosu area under the insolation conditions of summer and winter were investigated by using the Regional Atmospheric Modeling System (RAMS). Initially, horizontally homogeneous wind field were assumed on the basis of sounding data at the Kwangju upper-air station for days whose morning wind speeds were below 2m/s. In these days, the sea breeze prevailed in summer while the land breeze lasted for a few hours in the morning; the effect of synoptic winds was strong in winter with some inclusion of wind variations owing to the interaction between sea and land. The predicted wind direction at the location of the Yosu weather station captured an important change of the sea-land breeze of the observed one. The predicted wind speed and the air temperature agreed with observed ones in a reasonable range. In the morning, both in summer and winter, winds around the source location were diverged and became weak between the mountainous area to the southeast and the Kwangyang Bay to the north. Winds, however, accelerated while blowing to the east and south and blowing on the mountainous area. Complicated wind fields resulted in high pollutant concentrations at almost all receptors considered. These high concentrations in the morning were even comparable to the ISCST3 calculations with the worst-case and typical meteorological conditions designated by USEPA(1996). On the other hand, in the afternoon, the wind field was rather uniform even in the mountainous area with development of mixing layer and the concentration distributions being close to the Gaussian distributions.

• Ocean and Polar Research
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• v.34 no.2
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• pp.201-218
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• 2012

The purpose of this study is to investigate climatological variations from the sea surface temperature (SST), chlorophyll-a concentration (Chl-a), and phytoplankton size class (PSC), using NOAA AVHRR, SeaWiFS, and MODIS data in the South Sea of Korea (SSK) and East China Sea (ECS). 26-year monthly SST and 13-year monthly Chl-a and PSC data, separated by whole and nine-different areas, were used to understand seasonal and inter-annual variations. SST and Chl-a clearly showed seasonal variations: higher SST and Chl-a were observed during the summer and spring, and lower values occurred during the winter and summer. The annual and monthly SST over 26 years increased by $0.2{\sim}1.0^{\circ}C$. The annual and monthly Chl-a concentration over 13 years decreased by $0.2{\sim}1.1mg/m^3$. To determine more detailed spatial and temporal variations, we used the combined data with monthly SST, Chl-a, and PSC. Between 1998 and 2010, the inter-annual trend of Chl-a decreased, with decreasing micro- and nano-size plankton, and increasing pico-size plankton. In regional analysis, the west region of the study area was spatially and temporally correlated with the area dominated by decreasing micro-size plankton; while the east region was less sensitive to coastal and land effects, and was dominated by increasing pico-size plankton. This phenomenon is better related to one or more forcing factors: the increased stratification of ocean driven by changes occurring in spatial variations of the SST caused limited contributions of nutrients and changed marine ecosystems in the study area.

• Korean Journal of Community Nutrition
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• v.6 no.4
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• pp.592-603
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• 2001

Seasonal variations of nutrient intake ware evaluated through a 3-day dietary records in 196 Korean adolescents(86 males, 108 females) aged 13 - 15 years and living in urban and rural areas of Chungnam. The seasonal differences of nutrient intake were tested by repealed measure ANOVA. Comparing nutrient intakes among flour seasons using repealed measure ANOVA, mean values of daily intakes were higher in winter and autumn for most nutrients, and were the lowest in summer in the urban areas and in spring in rural areas. Girls recieved the largest amount of nutrients, except Ca and vitamin $B_12$, in winter and the lowest amount in summer, while in boys significant differences were not observed among the four seasons for meet nutrients, except fats, Mg, and vitamin E. Interestingly, the seasonal differences for many nutrients were more evident in rural areas than in urban areas. Vitamin A intake in urban areas was higher in winter and spring, while in rural oreas, in summer. Mean values of daily intakes as a percent of the RDA throughout the year in boys and girls ware 82.2% and 84.2% for energy and 88.9% and 82.7% for protein, respectively. Ca and vitamin A intakes were as low as 32.4% and 24.2% of the RDA in boys and 39.7% and 30.6% in girls. Intakes of Fe, Zn, folic acid and vitamin B$_{12}$ ranged from 40 - 60% of the RDA. The nutrients which showed the largest seasonal difference in the percent of RDA were vitamin E in boys and vitamin C, vitamin E, and Fe in girls. The index of nutritional quality(INQ) for Fe was significantly lower in autumn in both genders. The INQ for vitamin C in girls of both areas was much higher in winter. Annual mean adequacy ratio(MAR), an index of overall nutritional quality, ranged from 0.57 - 0.69, which was higher in winter than in other seasons. Conclusively, nutrient intakes of Korean adolescents showed seasonal variations, particularly in girls and in rural area. Thus, seasonal variations should be considered in the assessing nutritional status, particularly ill the rural areas of Korea.a.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.2 no.2
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• pp.120-133
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• 2008

This paper presents a novel approach for facial motion tracking and facial expression cloning to create a realistic facial animation of a 3D avatar. The exact head pose estimation and facial expression tracking are critical issues that must be solved when developing vision-based computer animation. In this paper, we deal with these two problems. The proposed approach consists of two phases: dynamic head pose estimation and facial expression cloning. The dynamic head pose estimation can robustly estimate a 3D head pose from input video images. Given an initial reference template of a face image and the corresponding 3D head pose, the full head motion is recovered by projecting a cylindrical head model onto the face image. It is possible to recover the head pose regardless of light variations and self-occlusion by updating the template dynamically. In the phase of synthesizing the facial expression, the variations of the major facial feature points of the face images are tracked by using optical flow and the variations are retargeted to the 3D face model. At the same time, we exploit the RBF (Radial Basis Function) to deform the local area of the face model around the major feature points. Consequently, facial expression synthesis is done by directly tracking the variations of the major feature points and indirectly estimating the variations of the regional feature points. From the experiments, we can prove that the proposed vision-based facial expression cloning method automatically estimates the 3D head pose and produces realistic 3D facial expressions in real time.

• The Bulletin of The Korean Astronomical Society
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• v.40 no.2
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• pp.45.1-45.1
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• 2015

Hayabusa is the JAXA's space mission that succeeded in sample-return from S-type asteroid (25143) Itokawa. During the rendezvous phase, more than a thousand of images were taken with the Asteroid Multi-band Imaging Camera (AMICA). It is valuable to study the regional variation of the optical properties on the asteroid using these images to know the generality and uniqueness of the returned samples. In addition, AMICA images are important in that they provide unique data set at low phase angle (i.e Sun-Itokawa-AMICA's angle) that have not been explored in the previous asteroidal missions. At the previous conference (2015 KAS spring meeting), we introduced our preliminary data analysis of AMICA data without considering the shape model of Itokawa and mentioned. In this study, we present a new result obtained through further analysis, taking account of the shape model of the asteroid. We thus utilized "plate_renderer" tool to derive Hapke model parameters at different terrains. It is found that the opposition amplitude (parameter B0) is consistent with those of the other S-type asteroids while the opposition width (parameter h) is significantly narrower than those of the other S-type asteroids. At this conference, we plan to describe the regional variation of photometric properties on Itokawa.

• The korean journal of orthodontics
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• v.17 no.1
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• pp.23-32
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• 1987

There are variations in regional cranial and facial balance as a normal developmental process and regional imbalances often tend to compensate each other to provide functional equilibrium. This study was designed to analyse the patterns of morphologic harmony and inharmony inherent in normal occlusion and malocclusion. The subjects consisted of 92 individuals with normal occlusion and 60 Class III malocclusion patients. Their lateral cephalograms were traced and analysed using the counterpart analysis described by Enlow. The normal occlusion group was divided into Normal Types A and B according to the relative positions of Points A and B. The following conclusions were reached: 1 The normal occlusion consisted of $28.3\%$ of Normal Type A and $69.6\%$ of Normal Type B. 2. The Normal Type A and B differed from each other in the morphology of the cranial base, the mandibular ramus and corpus, and the functional occlusal plane. The Normal Type B showed considerable mandibular protrusion effect in the effective dimension and alignment of the above factors. 3. Most normal individuals showed some degree of disharmony among morphologic factors but the deviations were relatively small. 4. The Normal Type B was less balanced than the Normal Type A. 5. More regional imbalances were involved in Class III malocclusion and the imbalances were more severe.

• Journal of Environmental Science International
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• v.10 no.3
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• pp.209-216
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• 2001

Dustfall particles were collected by the modified American dust jar (wide inlet bottle type) at 6 sampling sites in Pusan area from March, 1999 to February, 2000. Thirteen chemical species (Al, Ca, Cd, Cr, Cu, Fe, K, Mg, Mn, Ni, Pb, Si, and Zn) were analyzed by AAS and ICP. The purposes of this study were to estimate qualitatively various bulk deposition flux of dustfall and insoluble components by applying regional and seasonal distribution. Dustfall amount of regional variations were found in order of coastal zone, industrial zone, commercial zone, agricultural zone and residential zone, and seasonal total dustfall had higher concentrations during spring for 6.741 ton/${km}^2$/season, lower concentrations during summer for 1.989 ton/${km}^2$/season, and annual total concentration was 17.742 ton/${km}^2$/year. The regional distributions of enrichment factor show well-defined anthropogenic metals (Cd, Cu, Pb, and Zn) at industrial and agricultural zone, and contribution rate of soil particles were found in order of summer, fall, winter and spring. Factor loading effects of chemical composition of dustfall were found in order of road traffic emission source and combustion processed source, industrial activity source, soil source and marine source.

• Journal of Korean Society for Atmospheric Environment
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• v.4 no.1
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• pp.45-57
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• 1988

This is a close relationship between energy consumption and the way in which we develop and manage our regions. This study has estimated and compared energy requirements for the journey to work, resulting from alternative population and employment growth patterns in a rural-urban regional settlement of Korea. The broad scope of work was as follows: i) Select the study area ii) Formulate alternative growth patterns iii) Develop the Hansen and double-constrained gravity model iv) Application of Vogel's approximation method and the developed Hansen and gravity model to the case study area. v) Analyze the relationship between spatial structure, transport energy-requirements and environmental pollution. At issue here is the trade-off between air pollution averages and variations. Policies concentrating manufacturing industry and other regional facilities, for instance, may indeed reduce average pollution levels at the benefit of less-car miles, thus, reducing auto pollution, in the region, but increase local pollution peaks.

• The Plant Pathology Journal
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• v.40 no.2
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• pp.115-124
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• 2024

Citrus cultivation plays a pivotal role, making a significant contribution to global fruit production and dietary consumption. Accurate identification of viral pathogens is imperative for the effective management of plant viral disease in citrus crops. High-throughput sequencing serves as an alternative approach, enabling comprehensive pathogen identification on a large scale without requiring pre-existing information. In this study, we employed HTS to investigate viral pathogens infecting citrus in three different regions of South Korea: Jejudo (Jeju), Wando-gun (Wando), and Dangjin-si (Dangjin). The results unveiled diverse viruses and viroids that exhibited regional variations. Notably, alongside the identification of well-known citrus viruses such as satsuma dwarf virus, citrus tatter leaf virus, and citrus leaf blotch virus (CLBV), this study also uncovered several viruses and viroids previously unreported in Korean citrus. Phylogenetic analysis revealed that majority of identified viruses exhibited the closest affilations with isolates from China or Japan. However, CLBV and citrus viroid-I-LSS displayed diverse phylogenetic positions, reflecting their regional origins. This study advances our understanding of citrus virome diversity and regional dynamics through HTS, emphasizing its potential in unraveling intricate viral pathogens in agriculture. Consequently, it significantly contributes to disease management strategies, ensuring the resilience of the citrus industry.