• 한국환경과학회지
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• 제11권3호
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• pp.155-160
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• 2002

Using measured data at Daegu by tethersonde for the period of 1984∼1987, we have investigated the lower atmospheric boundary layer structure including relationships between inversion layer and meteorological factors(wind and temperature), and the inversion strength and inversion height. The inversion layer was defined from the vertical temperature profile and its strength was analyzed with the wind shear as well as the vertical temperature gradient. From October to January, measured inversion layer isn't destroyed, however, in June, after sun rise, it is destroyed by surface heating and mixed layer is developed from surface. According to Pasquill stability classes, the moderately stable cases dominated. It's the larger vertical temperature gradient the lower SBL height. We have introduced B(bulk turbulence scale) which indicated SBL height. It's larger B, the higher SBL height and vice versa. It was noted that the bulk turbulence scale (B) is appropriate to determine the stable boundary layer height.

• 한국환경과학회지
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• 제3권4호
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• pp.305-315
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• 1994

The field observation was carried out to investigate the characteristics of surface inversion layer at Kimhae using the feild observed date and upper layer meteorological data during 4-5 February 1993. The results of the study can be summarized as follows : The maximum height of surface inversion layer observed at Kimhae is 193m and the height of upper level inversion layer ranges from 2nm to 300m. The surface weather elements was influenced the formation of surface inversion layer. According to the pasquill stability and time variation of temperature with height, both the surface heating from insolation and the disturbance of upper level of inversion layer was influenced the disappearance of inversion layer. And the stability of surface temperature inversion layer generally belongs to the class of F, that of upper level temperature inversion layer commonly to the class of E.

• 한국환경과학회지
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• 제3권3호
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• pp.217-228
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• 1994

The climatological study of temperature inversion was conducted at the Tsukuba of Japan during the cold half year, the periods of which were both from October 1981 through March 1982 and from October 1982 through March 1983. Meteorological phenomena were observed to appear both from l0m to 200m above the ground and from the surface to 300hPa. The data collected from those phenomena were analyzed in terms of statistics and investigated from a synoptic point of view. The results are as follow. The dispersion of the surface inversion happens right after sunrise through the whole period. The higher the upper layer is, the later that happens. Up to a height of 200m, the wind speed at a height of 25m has the greatest effect on temperature, but on the other hand the wind speed at a height of l0m has the greatest effect on inversion intensity.

• 한국환경과학회지
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• 제7권2호
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• pp.195-202
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• 1998

The low level atmospheric obsewation carried out to Investigate magnitude, formation and dissipation of nocturnal surface Inversion layer, also to survey relation to each meterological parameter In Inversion layer at Pusan power plant for Oct. 13, 1996. As coastal area, the surface Inversion layer height was relatively high(186m), and after sunset unstable layer formated firom surface to around 40m, and the Inversion layer was left still in the upper layer. The surface Inversion layer dissipated at 0920LST perfectly. The layer that strong Inversion layer was formated, showed steep variation of potential temperature and wand speed and relative humidity.

• 한국환경과학회지
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• 제14권6호
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• pp.555-563
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• 2005

This study presents the characteristics of nocturnal inversion layer and their effect on the concentration variations of surface air pollutants using tethersonde and automatic weather station (AWS, 2 layer tower) system in Ulsan during 2003, The method for the distinction of inversion intensity was decided based on the sum of nocturnal temperature gradient. As the results, there was a close correlation (correlation coefficient of 0,76) between the maximum inversion height obtained from tethersonde and the sum of nocturnal temperature gradient. The air pollutant concentration was also directly proportional to the inversion intensity. When the inversion intensity was strong in the nighttime, ozone $(O_3)$ concentration was lower, while nitrogen dioxide $(NO_2)$ concentration was higher. The carbon monoxide (CO) concentration was gradually higher according to the nocturnal inversion intensity, whereas sulfur dioxide $(SO_2)$ concentration was relatively constant. In addition, we found that there was no correlation between the inversion intensity and TSP concentration.

• 한국대기환경학회지
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• 제13권2호
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• pp.103-113
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• 1997

The research described in this paper was conducted to estimate the stability and heat budget in planetary boundary layer (PBL) at Kimhae. The upper air observation was carried out during period from 3 Februsry 1993 to 5 February 1993 at Kimhae. The surface observation data used the one during period from 1 April 1994 to 31 March 1995. The maximum height of inversion layer observed at Kimhae was 310 m. Destruction of the inversion was simultaneously occurred at the surface and the mid-layer (200 $\sim$ 300 m), however the origin of destruction is different each other. The surface inversion is destructed by surface heating owing to growing radiation in surface but disappearance of the mid-layer inversion is related to the upper cold air movement.

• 한국운동역학회지
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• 제33권1호
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• pp.25-33
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• 2023

Objective: The purpose of this study was to investigate the differences in static arch height and ankle stability according to the preference for insole height and hardness in the arch area. Method: The study participants were 20 adult males (age: 22.7 ± 1.8 yrs., height: 175.3 ± 4.3 cm, body weight: 72.5 ± 7.7 kg). First, the arch heights of all subjects were measured in static postures (sitting and standing). The inversion and eversion movements of the ankle joint were analyzed during walking (1.3 m/s & 1.7 m/s) and running (2.7 m/s & 3.3 m/s). The variables (static arch height, and inversion and eversion angle of ankle joint) were compared by classifying groups according to the preference for the height and hardness of the arch of the insole. First, it was divided into a high arch insole preference group (HAG, n=8) and a low arch insole preference group (LAG, n=12) according to the preference for the arch height of the insole. Second, it was divided into a high hardness insole preference group (HHG, n=7), medium hardness insole preference group (MHG, n=7), and low hardness insole preference group (LHG, n=6), according to the preference for the arch hardness of the insole. Results: First, the range of motion (ROM) of inversion-eversion at the ankle joint during walking was statistically smaller in HAG than in LAG (p<.05). Second, the arch height change of HHG was statistically greater than that of MHG and LHG (p<.05). Conclusion: In the case of flexible flat feet with a large change in arch height, providing a high hardness arch insole that can disperse foot pressure can improve comfort. It was found that people with high medial and lateral sway of the ankle joint preferred a low arch insole, but it is necessary to differentiate and compare the insole heights of the arch part in detail. In addition, in the case of fast motion such as running, the preference for the arch height and hardness of the insole was not related to the static arch height and ankle stability.

• 한국운동역학회지
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• 제16권4호
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• pp.31-38
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• 2006

The purpose of this study was to investigate the effect of changing the steps height on the joint moment of lower extremity in stair-descent activity of elderly persons. Data were collected by 3-D cinematography and force platform. 9 male elderly subjects in the 60s and 70s participated in this study. All subjects performed a stair-descent in four different heights of stairs (10, 14, 18, 22cm) having 5 step staircase. The results were as follows. 1. For the step height of 22cm the maximum. plantarflexion moment was the smallest and the largest for the step height of 14cm. 2. There was not a statistical difference shown for the extension moment of the knee joint for the different height of steps. 3. There was not a statistical difference shown for the flexion moment of the hip joint for the varying height of steps but on average for the 18cm step this increased rapidly. 4. The smallest maximum. value for inversion moment was revealed for the step height of 10cm and this increased significantly for the step height of 22cm. 5. The smallest maximum. value for abduction moment of the hip joint was revealed for the step height of 10cm and this increased significantly for the step height of 22cm. 6. There was no significant difference shown for the maximum. abduction moment for the hip joint. The main conclusion is that there is a huge difference in the moment of the lower extremities for the elderly while walking down a stairs with a step height above 18 cm and that this moment increased or decreased rapidly under a condition of step height being 22cm. With the results from this research and related research of elderly walking upstairs it can be shown that the step height has a large role in the safety for the elderly.

• 대기
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• 제19권4호
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• pp.331-344
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• 2009

A sensitivity study has been performed using ARPS (Advanced Regional Prediction System) version 5.2.10 in a downslope windstorm case of 12-13 February 2006. The purpose of this study was to find out the role of the inversion layer of temperature mainly in relation to the strength of the downslope winds over the Yeongdong region located downstream of the Taebaek mountains. Under the conditions of N (Brunt-$V{\ddot{a}}is{\ddot{a}}la$ frequency)=0.008 and N=0.016, the effects of the presence of the inversion layer, its variation of height of the layer, and the depth of the layer were identified. The sensitivity experiments suggested that the inversion layer effected the downstream wind speed of the mountains under both conditions of N=0.008 and N=0.016, and notably when the inversion layer was located near the mountain crest the downstream wind speed of the mountains was strong (~ $27ms^{-1}$) only under the condition of N=0.016. In addition, when the atmosphere was rather stable (N=0.016) and the depth of the layer was relatively thin (765 m) the downstream wind speed of the mountains was the strongest (~ $30ms^{-1}$) among the sensitivity experiments.

• 한국전자파학회논문지
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• 제17권12호
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• pp.1172-1180
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• 2006

본 논문은 풀이 없는 지표면에서의 후방 산란 계수(backscattering coefficients)를 측정하고, 이 측정 결과를 이용하여 여러 표면 산란 모델들과 inversion 알고리즘의 성능을 비교, 분석하였다. 우선, R-밴드 주파수($1.7{\sim}2.0GHz$)에서 완전 편파 scatterometer를 이용하여 풀 층이 없는 지표면에 대해서 편파별로 후방 산란 계수를 측정하고, 동시에 수분 함유량과 표면 거칠기를 측정하였다. 그런 다음 측정된 지표면 변수들을 표면 산란 모델들에 입력하여 후방 산란 계수를 계산하고, 이 계산 결과를 측정 결과와 비교 분석하였다. 또한, inversion 알고리즘들을 적용하여 측정된 편파별 후방 산란 계수로부터 수분 함유량을 추출하고, 이 추출된 수분 함유량이 현장에서 측정한 수분 함유량과 잘 맞는지 여부를 확인하였다. 표면 산란 모델들 중에서 정확도가 높은 모델들을 제시하였으며, inversion 모델들의 계산 결과도 나타내었다.