• Korean Journal of Agricultural and Forest Meteorology
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• v.18 no.4
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• pp.233-241
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• 2016

Experiments were carried out to quantify the topographic effects on attenuation of sunshine in complex terrain and the results are expected to help convert the coarse resolution sunshine duration information provided by the Korea Meteorological Administration (KMA) into a detailed map reflecting the terrain characteristics of mountainous watershed. Hourly shaded relief images for one year, each pixel consisting of 0 to 255 brightness value, were constructed by applying techniques of shadow modeling and skyline analysis to the 3m resolution digital elevation model for an experimental watershed on the southern slope of Mt. Jiri in Korea. By using a bimetal sunshine recorder, sunshine duration was measured at three points with different terrain conditions in the watershed from May 15, 2015 to May 14, 2016. The brightness values of the 3 corresponding pixel points on the shaded relief map were extracted and regressed to the measured sunshine duration, resulting in a brightness-sunshine duration response curve for a clear day. We devised a method to calibrate this curve equation according to sky condition categorized by cloud amount and used it to derive an empirical model for estimating sunshine duration over a complex terrain. When the performance of this model was compared with a conventional scheme for estimating sunshine duration over a horizontal plane, the estimation bias was improved remarkably and the root mean square error for daily sunshine hour was 1.7hr, which is a reduction by 37% from the conventional method. In order to apply this model to a given area, the clear-sky sunshine duration of each pixel should be produced on hourly intervals first, by driving the curve equation with the hourly shaded relief image of the area. Next, the cloud effect is corrected by 3-hourly 'sky condition' of the KMA digital forecast products. Finally, daily sunshine hour can be obtained by accumulating the hourly sunshine duration. A detailed sunshine duration distribution of 3m horizontal resolution was obtained by applying this procedure to the experimental watershed.

• Journal of Environmental Policy
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• v.12 no.4
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• pp.119-132
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• 2013

Hosta longipes is one of the most popular ornamental perennials in use in Korea today, and is mainly used as a groundcover plant in urban shaded places. In this study, the pytoremediation effect of Hosta longipes was tested using four concentrations (Control, 100, 250 and $500mg{\cdot}kg^{-1}$) of Cd, Pb and Zn in soil. The plants were planted in $300mm{\times}200mm{\times}250mm$ drainless-containers, which were filled with a artificial amended soil for 7 months. The results showed that the contents of heavy metals cadmium and lead in the shoot of Hosta longipes increased with increasing heavy metal concentration levels exception of zinc. The amount of zinc, cadmium, and lead accumulated in roots were increased with heavy metal concentration levels up in soil. The shoot/root ratios(TF; translocation factor) values were found to be more than 80% of total Zn, Cd, and Pb take up by Hosta longipes. These results indicated that root is the major part for accumulation of heavy metal. The removal contents of zinc, cadmium, and lead increased significantly with the increasing heavy metal concentration in the soil, which was planted with Hosta longipes. The heavy metal concentration accumulation in plant/soil ratios (BF; bioaccumulation factor) values for three metals were found to be more than 30% in cadmium and lead, but lower in zinc treatments. The different responses of Hosta longipes suggest that in heavy metal contaminated soils the plant adsorbs available metals depending on the concentration soils in which they are present. Therefore, this species can be an efficient phytoremediator for soils contaminated with cadmium and lead in urban shaded places.

• Asian Journal of Turfgrass Science
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• v.20 no.1
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• pp.25-31
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• 2006

'Meyer' zoysiagrass(Zoysia japonica Steud.) is a popular turfgrass species used for transition zone golf course fairways and tees in mfd U.S.A golf courses because it is generally winter hardy while providing an excellent playing surface with minimal chemical and irrigation inputs. However, its functionality declines easily in many of the shaded areas of these courses. Reduced irradiance causes excessive shoot elongation, reduced tillering, and weak plants that are poorly suited to tolerate or recover from traffic and devoting. Trinexapac-ethyl (TE) effectively reduces gibberellic acid (GA) biosynthesis and subsequent shoot cell elongation. This study was initiated to evaluate TE effect on shoot elongation and stand persistence under two levels of shade in 'Meyer' zoysiagrass. A mature stand of 'Meyer' was treated with all combinations of three levels of shade(0%, 79%, and 92%) and three levels of monthly TE [0, 48 $g{\cdot}ha^{-1}$ a.i(0.5x) and 96 $g{\cdot}ha^{-1}$ a.i(1x)]. In full sun, the TE at 48 $g{\cdot}ha^{-1}$ a.i reduced clipping yield by 18% over a four-week period and, whereas the TE at 96 $g{\cdot}ha^{-1}$ a.i by 30% to 38%. Monthly application of TE at the 96 $g{\cdot}ha^{-1}$ a.i increased 'Meyer' tiller density in full sun and under 79% shade. Both rates of TE consistently reduced shoot growth under shade relative to the shaded control. Only the monthly applications of the TE at 96 $g{\cdot}ha^{-1}$ a.i consistently delayed loss of quality under 79% shade. Our results indicate TE can be an effective management practice to increase 'Meyer' zoysiagrass persistence in shaded environments.

• Journal of the Korean Institute of Landscape Architecture
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• v.37 no.3
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• pp.113-124
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• 2009

This study has attempted to calculate the intensity of illumination for the optimal growth environment of indoor plants after analyzing both damage to plant species and growth conditions as impacted by light conditions for the Kyobo Life Insurance greenhouse. The optical intensity of illumination has been estimated after investigating the problems of growth conditions based on an analysis of illumination by light condition, dead tree replacement cycle(weeks) and rate of damage of plant species. According to the investigation of illumination, the lowest difference was observed between the shaded spot in the south(531lux) and the sunny spot(602lux) while the largest difference(nearly 500lux) was detected between the shaded spot in the central area(210lux) and the sunny spot(782lux). According to an analysis of dead trees from 1990 to 2004, in terms of dead tree replacement cycle, Viburnum awabuki was the highest(161weeks), followed by Phyllostachys spp.(84weeks), Camellia japonica and Ternstroemia japonica(40weeks). Regardless of plant species, damage rate of plant were lower in the shaded spot and higher in the sunny spot. According to correlation and regression analyses with the intensity of illumination as an independent variable and the damage rate of plant species as a dependent variable, the damage rate of plant species increased as the intensity of illumination decreased. A dramatic decline in the rate of damage was observed at $500{\sim}600lux$. At 700lux, it reached the lowest level.

• Proceedings of the IEEK Conference
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• 1998.10a
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• pp.947-950
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• 1998

Geological structures such as fault and fracture patterns provide important information about preliminary exploration of mineralized areas and geological characterization. We apply a filtering method taking the sun's azimuth angle into account to a shaded relief image derived from a digital elevation model (DEM), by which even linear edges extending parallel to the sun direction can be effectively extracted. Then, Generalized Hough tranform is applied to extract lineanments which correspond to fault and fracture patterns.

• 한국약용작물학회:학술대회논문집
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• 2008.11a
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• pp.151-152
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• 2008

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.11a
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• pp.317-317
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• 2006

This study is about Sealant for LCD panel which used m manufacture of liquid crystal display device with LC dropping method, with the least contamination of liquid crystals, the best adhesion of glass and Improvement of photoreaction for shaded area.

• Journal of Ginseng Research
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• v.21 no.2
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• pp.115-118
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• 1997

Stratified American ginseng(Panax quinquefoilium L.) seeds were planted in a shaded greenhouse at four depths and in four different soil types to observe effects on emergence rate and root size. Seeding depth affected seedling emergence rates and the number of days required to complete emergence. The shape of the roots was affected by the texture of soil, especially percentage of sand.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.03a
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• pp.78-89
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• 2008

In this study the frost penetration depth along national roads in Korea were measured and analyzed over several years. The frost penetration depth was analyzed with respect to the Provinces of Korea and sunny/shaded areas. Additionally, the measurement results were compared to the formular of the US Army Corps of Engineers and Terada in Japan.

• 제어로봇시스템학회:학술대회논문집
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• 1991.10a
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• pp.730-735
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• 1991

In this paper, a graphics system supporting PHIGS and PHIGS+ is suggested and its hardware structure and software are described. The developed graphics system is a multi-processing system that uses 6 i860 RISC CPU's and supports PHIGS and PHIGS+ language in a hardware level. The developed system under tested is able to draw 160, 000 3-D polygones in one second when each polygon has 100 pixels and is shaded with Gouraud shading.