본 연구는 우리나라와 중국 간의 황해 환경에 대한 조사 필요성에 의하여 공동으로 수행한 결과 중 일부이다. 계절에 따른 황해 동물플랑크톤 군집의 변동을 보기 위하여 1998년부터 2003년까지 6년에 걸쳐 매년 1회 3개 선 24개 정점에서 동물플랑크톤을 채집하였다. 채집된 동물플랑크톤 시료는 일정 비율로 분할 후 생물량을 측정하였으며, 1998, 2000, 2002년 등 3개년에 걸쳐 주요 분류군의 경우 종수준까지 동정하였고, 1999, 2001, 2003년 등 3개년은 주요 분류군 수준까지 동정하였다. 이러한 결과에서 황해 동물플랑크톤 군집의 계절적 분포 변동에 따른 특성을 파악하였다. 조사시기에 따른 공간적 분포 양상에 있어 반복성은 나타나지 않았다. 가장 중요 분류군인 요각류의 경우 한국측 해역에서 높은 분포를 보였으며, 모악류의 경우 중국측 해역에서 높았다. 현 결과에서 조사시기 동안 황해를 대표하는 요각류는 Calanus sinicus, Paracalanus parvus s.l., Oithona atlantica, Corycaeus affinis 등 4종으로 이들 종의 밀도 변화가 수산자원의 양에 영향을 미칠 수 있는 중요한 요인으로 생각할 수 있다.

The purpose of this study was to compare spatio-temporal parameters during walking between patients with idiopathic Parkinson's disease and a control group matched for age, height, and weight. Thirty-three subjects were included in this study. Fifteen normal subjects (age, 63.3±5.8 yrs; height, 164.1±8.7 cm; weight, 60.7±17.5 kg) and eighteen patients (age, 64.0±7.7 yrs; height, 164.7±7.3 cm; weight, 63.6±7.7 kg) participated in the study. The Vicon 512 Motion analysis system was used for gait analysis in each group during walking, with and without an obstacle. The measured spatio-temporal parameters were cadence, walking speed, stride time, step time, single limb support time, double limb support time, stride length, and step length. Results in stride length and step length, when walking without an obstacle, showed a significantly greater decrease in the patient group compared to the control group. During walking with an obstacle, the patient group showed a significantly greater decrease in the step length as compared to the control group. For the control group, there were significant decreases in parameters of cadence and walking speed and increases in parameters of stride time, step time, and single limb support time when walking with an obstacle. The patient group had lower cadence and walking speed and higher stride time, step time, and single limb support time during walking with an obstacle than in walking without an obstacle. These results suggest that patients with Parkinson's disease who walk over an obstacle can decrease cadence, stride length, and step length. Further study is needed, performed with more obstacles and combined with other external cues, such as visual or acoustic guides.

2004년 2월, 5월, 9월 11월의 총 4회에 걸쳐 거제도 남동부 연안에 총 26개의 정점을 선정하고 저서동물 군집의 특성을 파악하였다. 표층 퇴적물의 입도 조성은 대체적으로 연안에서 다소 조립하였고 외해로 갈수록 세립화 되었으며, 연구 해역의 주요 퇴적상은 mud로 구성 되었다고 볼 수 있었다. 전체 연구기간동안 평균 저서동물의 서식밀도는 1,067개체 m-2이었다. 이 중 모든 계절에서 우점하는 동물군은 다모류로서 4계절 평균 871개체

1998년에서 2000년까지 2월과 5월, 8월, 11월 각 분기별로 영일만과 형산강의 수질의 변화에 대하여 조사하였다. 그리고 형산강에서 영일만으로 유입되는 담수가 영일만 수질에 미치는 영향에 대하여 고찰하였다. 수온은 5월과 8월에 높은 기온과 냉수대의 영향으로 표층수는 저층수보다 수온이 높으며, 염분은 형산강으로 부터 유입되는 담수의 영향으로 만 내측이 특히 낮은 특징을 나타내었다. 그리고 표ㆍ저층수의 염분차는 만 외측이나 만 중앙부에 비하여 만

The spatio-temporal distribution of four coexisting acartiid species in two subgenera Acartiura (Acartia hongi and A. omorii) and Odontacartia (A. erythraea and A. pacifica) was examined at seven stations in the southwestern waters of Korea, between Janua

The spatio-temporal distribution and seasonal fluctuations of phytoplankton community were carried out in the Southwestern parts of Deukryang Bay of the Korean South Sea from July 1997 to January 1998. A total of 60 species of phytoplankton belonging to 4

시아해의 수질환경과 식물플랑크톤 생물량의 계절변동 특성 및 식물플랑크톤 생물량변동에 영향을 미치는 환경요인을 파악하기 위해 1995년 2월,4월,7월과 10월 4회에 걸쳐 계절별로 23개 관측점의 표층과 저층 해수를 대상으로 현장조사를 실시하였다. 결과, 시아해는 2월에 최저수온, 8월에 최고 수온을 나타내나, 염분은 6, 7월에 높고 겨울에 낮은 특성을 나타내었으며, 연중 빠른 유속과 조석혼합 등으로 수층 간 혼합된 양상과 매우 낮은 투명도를 나타내고

득량만 식물플랑크톤 군집의 시.공간적 분포특성을 파악하기 위해 1992년 6월부터 1993년 4월까지 만내 38개의 관측점을 대상으로 월별 조사를 실시하였다. 결과, 득량만에서 출현이 확인된 식물플랑크톤 종은 식물성 편모조류 33종을 포함 50속 75종이 동정되었다. 계절별로는 여름과 가을에 비교적 다양한 종이 출현을 보이고 있는 반면, 봄과 겨울에 단순한 종 출현 특성을 나타내었다. 우점종은 연간 규조류에 의해 지배되고 있으며, 여름에 P. alata

The purpose of this study is to elucidate the spatio-temporal characteristics of ultrafine dust generation in East Asia and the synoptic climate patterns related to its dispersal which has its adverse effects on public health across East Asia. To achieve this purpose, Level 3 monthly Aerosol Optical Depth (AOD) data extracted from MODIS satellite imagery (MOD08_M3) representing particle matters less than 2.5 micrometer (PM2.5) and the NCEP-NCAR reanalysis I upper-level climatic data associated with the exacerbation of ultrafine dust problem are analyzed for the recent 20-year (2001-2020) period. Analyses of long-term average MOD08 data show that high AOD value exceeding 0.5 or more frequently occurred in populous cities in East Asia but mainly in the vicinity of densely populated large rivers and the eastern lowlands in China between mid-winter and mid-spring, which is attributable to the accumulation effects of continuous fossil fuel consumption for heating and manufacturing. Despite the overall decreasing trend of ultrafine dust across China in the 2010s, the weakened westerlies in the warmer climate as well as its continuous generation from the densely populated industrial regions of China provide a favorable synoptic climate condition for frequent severe ultrafine dust problems across East Asia including South Korea. These results indicate that ultrafine dust from China is a long-lasting transboundary environmental problem across East Asia, which needs long-term international cooperation in developing the sustainable policies.

The purpose of this study is to explore spatio-temporal patterns of extreme low human-sensible temperature (HST) across Mt Halla (1,950m), Korea. To do this, decadal (2011/12-2020/21) averages of daily or hourly windchill index (WCI), which quantifies HST considering the combined effects of low temperature and strong wind, are calculated for 24 weather stations in Mt Halla. Time series of decadal average daily mean show that extreme low HST events with moderate risk level (-27~-10°C) occur in mid-winter (mid-January~early February) around the high mountainous areas of Mt Halla, while such risk does not exist in the low-elevated coastal regions of Jeju Island under subtropical climate. Strong wind around the subalpine climate belt lowers HST by 5°C than air temperature in mid-winter. In extreme cases when the advection of northerly cold wind is intensified by the west high-east low pressure pattern in East Asia, the HST around the peak of Mt Halla can be lowered to high risk level (-39~-28°C) in the early morning times of mid-winter days. These information about mountain bioclimate may help establish mountain extreme climate warning systems, which are needed to protect mountaineers from potential life-threatening accidents caused by extreme low HST events over high mountains such as Mt Halla.

목적: 본 실험의 목적은 자극의 속도와 방향이 예측타이밍 반응시에 발생하는 안구운동패턴과 반응의 시공간적 정확성, 그리고 눈과 손의 협응패턴에 미치는 영향을 분석함으로써 시공간적 정확성을 요구하는 예측타이밍 과제를 수행할 때 자극에 대한 시각적 지각과 활동이 결합되는 과정을 연구하는 것이다. 방법: 12명의 오른손잡이 남자피험자가 다양한 속도와 방향으로 이동하는 자극이 목표영역에 도달하는 시점과 일치되게 철필로 자극을 치도록 요구받았다. 피험자가 과제를 수행할 때 안구운동패턴과 반응결과를 측정하였으며, 자극의 속도와 방향에 따른 주시점 이동패턴의 차이, 동작종료시점에서의 주시점 위치와 자극 위치 사이의 간격, 그리고 주시점과 철필위치의 시공간적 관계를 분석하였다. 결과: 예측타이밍 반응의 시공간적 오차는 자극속도가 빠를수록 증가하였으며, 단속성 안구운동의 잠복기와 빈도, 그리고 주시점 고정기간은 자극속도가 느릴수록 증가하였다. 모든 자극속도 조건에서 주시점은 반응이 종료되기 전에 목표영역에 먼저 도달하였으며, 자극속도가 느릴수록 주시점과 철필의 시간적 연결은 증가하였으나, 주시점과 자극, 그리고 주시점과 철필의 공간적 간격은 감소되었다. 결론: 이러한 결과는 자극의 속도와 방향에 대한 시각적 지각에 근거를 두고 발생하는 주시점의 이동패턴이 예측타이밍 반응의 시공간적 정확성을 결정하는 과정에서 주요 기준으로 작용할 수 있으며 손의 반응과 시공간적으로 연결되어 있음을 시사한다.

In this study, the spatio-temporal patterns of summertime thermal environments in the two subtropical cities (Jeju and Seogwipo) of Jeju Island, Korea are examined. Long-term average data from Jeju and Seogwipo show that higher human sensible temperature (HST) than air temperature (T) due to the high humidity effects associated with warm sea surface temperature around Jeju Island is most distinct during mid-summer period (late July-early August). Comparatively, their trend analyses reveal that summertime intra-seasonal changes with more increasing HST than T are most obviously observed in late summer (late September-early October) and regionally in Seogwipo. According to the hourly temperature-humidity data measured at approximately 30 HOBO temperature-humidity sensors deployed in the two subtropical cities during 2019 summer, the greater HST than T during mid-summer period maximizes up to 6.2°C and 7.0°C across the urban areas of Jeju and Seogwipo, respectively in early afternoon, leading to consecutive inter-daily heat wave events. The examination of their spatial patterns demonstrates that bioclimatic heat waves in these two subtropical cities are affected primarily by the urban heat island phenomenon. However, it should not be overlooked that local moisture advection from the warm ocean adjacent to the subtropical cities can modify the stronger heat wave pattern toward urban cores. It is also notable that according to comparisons of local HST and T distributions between impervious urban cores and neighboring urban parks, not only the size of green space but also other ecological properties including species of vegetation may be crucial factors to the mitigation of hot thermal environments in subtropical cities during summers.

Water quality is characterized by various complex factors. Therefore, a systematic understanding of water quality trends is required to carry out a proper evaluation. In this study, we analyzed the spatio-temporal water quality characteristics of the Nakdong River using five-year data from 2012 to 2016. Data was collected on the pH, DO, BOD, COD, SS, TN, TP, TOC, WT, EC, NH3-N, NO3-N, PO4-P, Chl-a, rainfall, and total and fecal coliforms. A total of 38 water quality measurement stations, from Andong1 to Gupo, were considered. Statistical analyses including trend, cluster, and factor analyses were conducted to identify the dominant water quality components affecting the Nakdong River. The Nakdong River was spatially classified into three groups for up-stream (Andong1 to Sangju1), mid/up-stream (Donam to Dalseong), and mid/down-stream (Hwawonnaru to Gupo) data collection, and temporally into two groups for summer/fall (7~10), and the rest of the season (11~6) data. The water quality of the entire Nakdong River showed trends similar to the mid/down-stream section, which indicates the importance of water quality management in this section. Suspended solids, phosphorus, and coliform groups were established as important factors to be considered in the summer/fall season across the river, especially in the mid/down-stream section. Nitrogen and organic matter were identified as important factors to be considered in the rest of the season, especially in the mid/up-stream section. This study could help determine the water quality components that should be intensively monitored in the Nakdong River.

Temporal and spatial characteristics of the frequency of several weather types and the change in air pollutant concentrations according to these weather types were analyzed over a decade (2007-2016) in seven major cities and a remote area in Korea. This analysis was performed using hourly (or daily) observed data of weather types (e.g., mist, haze, fog, precipitation, dust, and thunder and lighting) and air pollutant criteria (PM10, PM2.5, O3, NO2, CO, and SO2). Overall, the most frequent weather type across all areas during the study period was found to be mist (39%), followed by precipitation (35%), haze (17%), and the other types (≤ 4%). In terms of regional frequency distributions, the highest frequency of haze (26%) was in Seoul (especially during winter and May-June), possibly due to the high population and air pollutant emission sources, while that of precipitation (47%) was in Jeju (summer and winter), due to its geographic location with the sea on four sides and a very high mountain. PM10 concentrations for dust and haze were significantly higher in three cities (up to 250 μg/m3 for dust in Incheon), whereas those for the other four types were relatively lower. The concentrations of PM2.5 and its major precursor gases (NO2 and SO2) were higher (up to 69 μg/m3, 48 ppb, and 16 ppb, respectively, for haze in Incheon) for haze and/or dust than for the other weather types. On the other hand, there were no distinct differences in the concentrations of O3 and CO for the weather types. The overall results of this study confirm that the frequency of weather types and the related air quality depend on the geographic and environmental characteristics of the target areas.