• Current Optics and Photonics
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• v.3 no.3
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• pp.210-214
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• 2019

The allowable path-deviation time of aircraft in a free-space optical communication system has been estimated from various trajectories, using different values of aircraft speeds and turn rates. We assumed the existence of a link between the aircraft and a ground base station. First, the transmitter beam's divergence angle was calculated through two different approaches, one based on a simple optical-link equation, and the other based on an attenuation coefficient. From the calculations, the discrepancy between the two approaches was negligible when the link distance was approximately 110 km, and was under 5% when the link distance ranged from 80 to 140 km. Subsequently, the allowable path-deviation time of the aircraft within the tracking-error tolerance of the system was estimated, using different aircraft speeds, turn rates, and link distances. The results indicated that the allowable path-deviation time was primarily determined by the aircraft's speed and turn rate. For example, the allowable path-deviation time was estimated to be ~3.5 s for an aircraft speed of 166.68 km/h, a turn rate of $90^{\circ}/min$, and a link distance of 100 km. Furthermore, for a constant aircraft speed and turn rate, the path-deviation time was observed to be almost unchanged when the link distance ranged from 80 to 140 km.

• Journal of Astronomy and Space Sciences
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• v.15 no.1
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• pp.197-208
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• 1998

Ground track manintenance maneuver simulations for the KOMPSAT spacecraft are performed for three and half years. Both longitude targeting and time targeting strate-gies are applied for in-plane maneuvers. The nominal longitude bands of maneuvers for $\pm5km$ and $\pm10km$ are applied for the longitude targeting and the 21-day maneuver time duration is used for the time targeting. Daily solar flux values for the simulation period are derived from the previous solar cycle values. Atmospheric drag formula for the KOMPSAT orbit altitude is derived from Jacchia model using polynomial and sinusoidal curve fitting. Total required delta velocity and proper time between successive maneuvers are estimated during ground track maintenance maneuver simulations.

• Journal of the Korean Society of Food Science and Nutrition
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• v.22 no.6
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• pp.792-796
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• 1993

The synthesis alcohol-oxidase[EC 1.1.3.13] was investigated in the yeasts, Candida boidinii CBS 8106 and C. boidinii CBS 2428, during growth on different carbon sources. Alcohol-oxidase was undetectable in all strains submitted to the test in the mineral salts medium containing 1.0% glucose, but its production was rapidly increased when the carbon source was changed glucose to 1.0% methanol after 24hrs of incubation. When cells were grown on the various carbon sources (glucose, xylose, lactose, glycerol, galactose, saccharose, sorbose, lactic acid or acetic acid), the alcohol-oxidase activity was undetected. These carbon sources together with methanol yielded far better synthesis of alcohol-oxidase than in the case of carbon sources alone. Alcohol-oxidase was active towards alcohol of shorter alkyl-chain length than C5 and unsaturated alcohols. Its affinity for these alcohols decreased with the increasing length of the alkyl-chain. The apparent Km values for the methanol of Candida boidinii CBS 8106 and C. boidinii CBS 2428 were 1.96 and 1.21, respestively.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.8
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• pp.1157-1163
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• 2011

This study was conducted to determine the effect of the inclusion of different levels of ensiled cassava leaves (variety KM94) in the diets on performance and carcass characteristics of growing pigs in Vietnam. A total of 40 crossbreds pigs (Large White${\times}$Mong Cai, 20 males and 20 females) with an initial live weight of 23.5 kg (SD = 0.86) were randomly allocated to one of the four pens across 5 units. Four experimental diets were formulated for two growth periods, period 1 (60 days) for 20 to 50 kg and period 2 lasted 30 days, from 50 kg until slaughter. Four diets were formulated containing inclusion levels of ensiled cassava KM94 leaves diet of 0, 10, 15 and 20% in the DM. Diets were formulated based on previously determined ileal amino acid digestibility values of the KM94 products and were isonitrogenous and isocaloric on a metabolizable energy basis. Each pen of pigs was randomly assigned to one of the four dietary treatments. Dry matter intake and final weight tended to decreased with increasing levels of ensiled cassava KM94 leaves in the diet while there was a significant (p = 0.022) decrease in average daily gain. Protein depositions of the F1 pigs tended (p = 0.093) to decrease with increasing inclusion levels of ensiled cassava KM94 leaves. There was no significant difference in feed conversion ratio, carcass quality and fat gain between the groups of pigs. There were clear differences in feed costs among the experimental diets (p = 0.001) with increasing levels of ensiled cassava KM 94 leaves in the diet reducing feed costs. It was concluded that, in diets for growing pig, inclusion of ensiled cassava leaves reduces growth rate of pigs in Vietnam but increases profitability as measured by feed costs.

• Korean Journal of Remote Sensing
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• v.26 no.4
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• pp.411-419
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• 2010

The type of forestland value was evaluated using various thematic maps, satellite images, and aerial photograph of Namyangju, Based on GIS analysis, forestland value was classified into 4 kind types; conservation, production, recreation, and development values. Finally, the comprehensive analysis map of forestland value was made according to the priority order of value assessment. Among the whole forestland of Namyangju, conservation value area is $195km^2$, high production value area $96km^2$ except the conservation value area, high recreation value area $59km^2$, and the high development value area is $11km^2$. Henceforward, The value evaluation system of forestland by using GIS is to be very applicable for the scientific management of forestland, according to the periodic data update.

• Journal of the korean academy of Pediatric Dentistry
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• v.49 no.4
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• pp.453-467
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• 2022

The purpose of this study was to evaluate the accessibility of pediatric dental clinics and quantitatively compare the regions with the best and worst accessibility to pediatric dental clinics in South Korea using the geographic information system. Seoul city showed the highest density of pediatric dental clinics, while Gyeongbuk and Jeonbuk provinces showed the lowest density. Seoul city had a service area ratio of 100% in all districts on a 10 km basis. In Gyeongbuk and Jeonbuk provinces, more than half of the districts had a service area ratio of 0%. In Seoul, the average distance from elementary school to the nearest pediatric dental clinic was 3.45 km. The average distance values were 43.66 km and 40.57 km in Gyeongbuk and Jeonbuk provinces, respectively, which were 12.66 times and 11.76 times longer than the average distance in Seoul city.

• Journal of the Korean Data and Information Science Society
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• v.28 no.5
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• pp.1133-1144
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• 2017

Cluster analysis with meteorological data allows to segment meteorological region based on meteorological characteristics. By the way, meteorological observed data are not adequate for cluster analysis because meteorological stations which observe the data are located not uniformly. Therefore the clustering of meteorological observed data cannot reflect the climate characteristic of South Korea properly. The clustering of $5km{\times}5km$ gridded data derived from a numerical model, on the other hand, reflect it evenly. In this study, we analyzed long-term grid data for temperatures and precipitation using cluster analysis. Due to the monthly difference of climate characteristics, clustering was performed by month. As the result of K-Means cluster analysis is so sensitive to initial values, we used initial values with Ward method which is hierarchical cluster analysis method. Based on clustering of gridded data, cluster of meteorological stations were determined. As a result, clustering of meteorological stations in South Korea has been made spatio-temporal segmentation.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.18 no.1
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• pp.1-12
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• 2015

Beginning of the human ecology in 1920s, the efforts for applying the environmental values to a policy have been embodied by the enactments of international agreement and relevant laws. The government has been struggling to adopt the environmental values for the policy by enacting the relevant laws and establishing the environmental value evaluation information (environmental conservation value assessment map, eco-natural map, biotope map). In spite of the efforts to apply the environmental value assessment information for the habitat potential of wildlife, the application is being challenged by the discrepancy in methods and criteria. Thus this study intends to measure the potential of wildlife habitat and apply it to the spatial value classification for the application plan of wildlife habitat potential in policy. Maxent was used for the habitat potential and the land types were classified depending on the surface and land use pattern of cadastral map. As a result, the policy matrix including conservation strategy(CS), restoration strategy(RS), practical use strategy(PS) and development strategy(DS) has been deduced as CS $13.05km^2$(2.38%), RS $1.64km^2$(0.30%), PS $162.42km^2$(29.57%) and DS $8.56km^2$(1.56%). CS was emerged mostly on forest valleys and farmlands, and RS was appeared in the road area near the conservation strategy areas. Boryung downtown and Daecheon Beach were the center of DS, while the forest and farmlands were presented as PS. It is significant that this study suggest the new approaching method by comparing the wildlife habitat potential with the land type. Since this study evaluated the environmental value by one species of leopard cat (Prionailurusbengalensis) with Maxent model, it is necessary to apply the habitat potential measuring method for various target species as further research.

• The Journal of Korean Medicine
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• v.43 no.1
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• pp.33-41
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• 2022

Objectives: Drug-induced blockade of the human ether-à-go-go related gene (hERG) potassium ion channel causes acquired long QT syndrome, which is known to cause cardiac arrhythmias and be fatal. To establish safety evidence of herbal formulae, we evaluated the effects of 31 herbal formulae on hERG channel activity. Methods: The current through hERG channel was measured by changing the membrane voltage before and after treatment with 31 herbal formulae in HEK 293 cell overexpressing hERG channel using a whole-cell patch clamp system. The current-voltage curves and the activity curves were fitted, and the hERG activity and 50% inhibitory concentration (IC₅₀) according to each herbal formula were calculated. Results: Chokyungjongok-tang, Oncheong-eum, and Cheongsangbangpung-tang strongly inhibited the hERG activity, with IC₅₀ values of 67.67, 141.2, and 296.3 ㎍/mL, respectively. Yeonkyopaedok-san, Eunkyo-san, Ukgan-san gajinphibanha, Daegunjoong-tang (except Oryzae gluten), Insamyangyoung-tang, Banhahubak-tang, SokyungHwalhyul-tang, Jodeung-san, Hyeonggaeyeongyo-tang, and Bangkeehwangkee-tang weakly inhibited hERG activity, with IC₅₀ values ranging from 400 to 1000 ㎍/mL. The other 18 herbal formulae showed very weak hERG activity inhibition of less than 50% at the highest concentration (1000 ㎍/mL). Conclusion: This study provided safety information on cardiotoxicity by cardiac arrhythmia risk assessment of herbal formulae, and is expected to be a reference data for predicting the safety and risk of herbal formulae.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.2D
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• pp.251-258
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• 2006

This study is to develop an estimation method of freeway design capacity through the analysis of time headway distribution in continuum flow. Traffic flow-speed diagram and time headway distribution plotted from individual vehicle data shows: a) a road capacity is not deterministic but stochastic, b) time headway distribution for each vehicle speed group follows pearson type V distribution. The freeway design capacity estimation model is developed by determining a minimum time headway for capacity with stochastic method. The estimated capacity values for each design speed are lower when design speed ${\leq}80km/h$, and higher when design speed ${\geq}106km/h$ in comparison with HCM(2000)'s values. In addition, The distinguish difference is that this model leads flexible application in planning level by defining the capacity as stochastic distribution. In detail, this model could prevent a disutility to add a lane for only one excess demand in a road planning level.