• Current Research on Agriculture and Life Sciences
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• v.17
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• pp.71-77
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• 1999

The study aimed to identify effect of shading rate and duration on the growth and flowering of Lilium species in faring culture. Plant height of 'Gelria' and 'Casablanca' increased by higher shading at early growth stage, whereas that of 'Jolanda' and 'Dream Land' decreased. Also, plant height of 3 cultivars except 'Gelria' were longer by higher shading at whole growth stage, that of 'Gelria' was shorter as compared to in untreated plants. In cultivar 'Gelria', blasting increased and days to flowering shorted in higher shading only except 100% shading treatment at early growth stage. In 100% shading treatment, Blasting of 'Jolanda' was occurred 15.7% and the number of flower buds of 'Dream Land' and 'Casablanca' were reduced. Flower buds of 'Gelria' were not induceded in continued shading condition regardless of shading degree, the number of flower buds and flower size of 'Jolanda' and 'Dream Land' was reduced by 75% and 50% shading, respectively and in 'Casablanca', days to flowering was longer by shading at whole growth stage. Growth of daughter bulbs in 'Gelria', 'Jolanda' and 'Dream Land' was not influenced by shading at early growth stage but those of 'Casablanca' was inactive. Whereas that of 4 cultivars were inactive in continused shading condition.

• Journal of The Korean Society of Grassland and Forage Science
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• v.37 no.4
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• pp.283-289
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• 2017

The present study was carried out to explore the potential effect of shading degrees on yields and nutritive values of forage in forest-grassland. This experiment was conducted this study under different natural shading at National Institute of Animal Science, Cheonan province in Korea, for 2 years (from 2015 to 2016). This experiment was consisted of four different shading degrees, such as full sunlight (control, 10% below), 25% of shading, 35% of shading, 50% of shading. Pasture species used in this study were orchardgrass 'Kodiwin', perenial ryegrass 'Linn', tall fescue 'Purumi', kentuky bluegrass 'Kenblue', and white clover 'Ladino'. Botanical composition of orchardgrass was higher than that of perenial ryegrass, tall fescue and kentuky bluegrass. Dry matter (DM) yields of forage decreased as increasing shading degrees. DM yields of forage significantly decreased as increasing shading degrees and lots of cutting times under increasing shading degrees decreased DM yields of forage. The content of crude protein increased as increasing shading degrees and the contents of acid detergent fiber (ADF), neutral detergent fiber (NDF), the activity of total digestible nutrient (TDN) and in-vitro digestibility (IVD), and relative feed value (RFV) were similar in control and different shading. This study suggests that orchardgrass is major component for forest-grassland and establishment of orchardgrass can be improved by increasing shading degrees.

• Korean Journal of Plant Resources
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• v.34 no.5
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• pp.462-469
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• 2021

Maesa japonica (Thunb.) Moritzi & Zoll. is a rare evergreen shrub that occurs in west Gotjawal, Jeju island, Korea. This study was conducted to investigate effects of an artificial shading on flowering and growth characteristics of M. japonica seedlings. The level of shading had been set to be 35%, 55% and 75% using shading net. The stage of flowering and flowering ratio, seedling height, the number of leaves and stems, leaf area were measured. Flowering timings were delayed by shading. The number of flowering seedlings per plot and inflorescences per seedling were the most in 55% shading level. Tendency of decreased seedling height with increased shading level was shown. The number of leaves and stems were the fewest values in 75% shading level. The increased biomass with decreased shading level was statistically significant. Aboveground and underground biomass were 2.1 and 1.7 times higher in shading 35% than in shading 75%, respectively. Meanwhile, all seedlings in non-shading plots were dead in winter. Such might be speculated as results of the light stress. As a result, we conclude that M. japonica vitally demands the shading for growth and the optimal shading levels for growth and flowering are 35% and 55%, respectively.

• Journal of the Korean Institute of Navigation
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• v.9 no.1
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• pp.95-109
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• 1985

It has been generally known that the chattering of an AC electromagnetic contactor due to the fluctuation of attracting force is the primary cause of its abrasion and noise. To reduce this chattering effect, an AC electromagnetic contactor is mostly fitted with a shading coil which works the role to make difference in phases of two distinct components of attracting force. The theoretical interpretation of an AC electromagnetic contactor with shading coil and the equation of its attracting force per unit wattage consumed have already been proposed, however, few explications so far have been made on the determination of optimal circuit constants of shading coil. In this paper, the auther constructs a circuit model of an AC electromagnetic contactor with shading coil which is based on the theoretical interpretation of shading coil examined to be valid by experiments under some assumptions, and defines the equation of attracting force without chattering per unit wattage consumed as a performance function for determining the optimal circuit constants of shading coil. And then, the optimal circuit constants maximizing the performance function are determined by means of computer simulation founded on the above circuit model and the characteristics of those circuit constants are examined with special attention to the coupling coefficient.

• Journal of Forest and Environmental Science
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• v.36 no.1
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• pp.55-61
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• 2020

In this study, basic data with respect to the introduction of Hipphophae rhamnoides L. and its cultivation in Korea could be obtained. According to the size of the plug cell tray, Chinese origin's rate of seed germination was relatively high in 128 plug cell tray, and growth was vibrant in 50 plug cell tray. The germination and growth of Russian origin seeds showed that they were relatively effective in 50 plug cell tray and with respect to soil environment, TKS-2 soil with untreated shading relatively promoted both germination and growth for Chinese origin, the rate of germination was high in bed soil for horticulture and growth result was good in TKS-2 in the case of Russian origin. It was confirmed that the germination rate of Chinese origin H. rahmnoides L. was highest in untreated shading and the shoot growth was vibrant in 70% shading while the growth in roots was vibrant in the untreated shading. In the Russian origin, H. rhamnoides L. the germination rate in 30% and 70% shading was about 50% which was higher than that in the untreated shading and general growth was vibrant in 30% shading.

• Journal of Environmental Science International
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• v.29 no.2
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• pp.167-175
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• 2020

The purpose of this study was to investigate the effect of shading on the growth and productivity of strawberries. Photosynthesis was normally achieved under natural light without shading treatment, and vegetative growth of under- and aboveground part of strawberry plants were excellent. Strawberry fruit productivity and quality were different depending on shading conditions. In natural light, they were improved possibly by balanced vegetative and reproductive growth. However, under light-shading conditions with insufficient sunshine, photosynthetic activity deteriorated and carbohydrate production was therfore inadequate; this adversely affected plant height and quality. The negative effects were more pronounced at 50% shading condition. Shading treatments resulting in insufficient sunshine had a detrimental impact on plant productivity and growth; this implies that proper shading conditions could heip improve yield and fruit quality.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.25 no.4
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• pp.91-98
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• 1980

Three kinds of shading materials, styrol-foam board, pine board and polytex, were examined and compared with ordinary shading, and the effects of light intensity and the temperature under the shadings on the photosynthesis and the root growth of the Korean ginseng were studied to improve the shading on the ginseng field. The amounts of photosynthesis of the ginseng leaves at 2$0^{\circ}C$ were significantly larger than those at 3$0^{\circ}C$ in the same light intensity. At 2$0^{\circ}C$, the maximum photosynthesis occured at 35, 000 lux, but at 3$0^{\circ}C$, the amount of photosynthesis was rapidly reduced by higher light intensity over 26, 200 lux. The best root growth occurred under the polytex shading and the styrol-foam board shading was also effective for ginseng growth. Under the ordinary shading, the root growth of ginseng planted on rear line was very poor but under the styrol-foam or the polytex shading, the root growth showed little difference between the ginsengs planted on rear line and front line.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.18 no.1
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• pp.83-89
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• 2015

Thalictrum species belongs to the Ranunculaceae and are perennial landscape plants which are available in the garden and potted plants. This experiment was conducted to find out the basic data for the growth effects of fertilizer levels and shading rate in seedling plug cell tray in the Thalictrum rochebrunianum, T. uchiyamai and T. coreanum. For T. rochebrunianum and T. uchiyamai, growth increased by all fertilizer level treatments as compared to non-treatment. Hyponex 1000 times of treatment showed the highest growth. All growth increased in 35% shading as compared to other treatments for T. rochebrunianum and T. coreanum. But, for T. uchiyamai growth increased in 55% shading. In general, growth of three Thalictrum species was worse in 75% shading, as compared to other shading rates. Based on the results, Thalictrum species seedling can be produced by 35-55% shading and fertilization of Hyponex 1000 times by using plug tray.

• Asian Journal of Turfgrass Science
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• v.7 no.1
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• pp.5-12
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• 1993

This experiment was conducted to study on the morphological change and growth retardation of Korean Lawograss (Zoysia japonica Steud.) under various shading degrees. Dada of plant height, No. of tiller, No. of stolon, No. of rhizome and fresh weight were measured on the l47days after transplanting in 1991. The results are summarized as follows. Plant height was increased at 30% shading degree or over, Maximum plant height was observed at 60% shadeing degree which was 24.2 cm. while full sunlight(control) was most shorted as 10.1 cm. Plant height rapidly was increased as to shading degree increase. The decreasing rate was lower in tiller number and stolon number(top parts of plant) compared with the rhizome number(under ground part) was severely decreased at 30% to 60% of shading. To increase the shading degree, rhizome number was most severely decreased under shading degrees. As degree of shading increase to 30%, 60% and 90%, fresh weight decrease to 66%, 44%, 22% to full sunlight, respectively. Relative growth retadation of Korean lawngrass was decreased by the order of number of rhizome, fresh weight, number of tiller, number of stolon. And these characters were highly significant accord-ing to the different shading degrees.

• Proceedings of the SAREK Conference
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• 2006.06a
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• pp.854-859
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• 2006

This study aims to evaluate the effect on indoor environment by the application of the shading device on winter season. Therefore, thermal and visual experiments were conducted at two side-by-side mock-Lip test cells which were equipped with the shading device(venetian blind & roll blind) at interior and exterior side of the window. The results of this study are as follows: 1) At night of winter, the shading device can prevent internal heat from going out. 2) Exterior shading device is more effective in winter as well as in summer. 3) At daytime of winter, the shading device can provide the uniformity of illuminance, and the interior shading device is more effective.