• Journal of Practical Agriculture & Fisheries Research
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• v.25 no.4
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• pp.84-89
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• 2024

Light is an important component among which plays a crucial role in determining the production and quality of fruit trees. Since the disturbance of light directly leads to reduced photosynthetic efficiency, their damage can be increased especially in fruit trees such as Japanese apricots with a short growing time. In this study, we investigated how the effects of shading condition can affect the production and quality of Japanese apricots according to increased damages by light disturbance in the main orchard complex. The average photosynthetically active radiation (PAR) level in Japanese apricots was rapidly dropped as the shading time was increased compared to the control (304 μmol/m²/s) and the PAR level decreased to 142 μmol/m²/s after shaded for eight hours. The maximum photosynthetic efficiency, with a PAR value of 900 to 1,000 μmol/m²/s, corresponds to the time period without shading and the time period with 2 hours of shading, and these times range from 11 a.m. to 3 p.m. And the time period for shading for 4 hours was from 1:00 p.m. to 2:00 p.m., and under conditions of shading for 6 and 8 hours, the effect was a low amount of light. There was no difference in the weight of Japanese apricots during 2 hours shading time, however, it was significantly reduced as shading time were increased. The difference of the acid content and L/D ratio was not significant on shading time, but the SSC was decreased as times going on. In conclusion, our results indicate that the shading for more than 2 hours make negative effects to decrease the weight and SSC and the yield and affects directly to drop in fruit quality.

• Horticultural Science & Technology
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• v.35 no.4
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• pp.418-430
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• 2017

The objective of this study was to understand the combined effect of shading treatment and harvest time on pungency, ascorbic acid content, market-quality pepper yield, and photosynthetic activity in a yellow 'Star Flame' and 'Fire Flame' F1 hybrid pepper cultivar (Capsicum annuum). Plants were cultivated in a greenhouse under white, red, and green shading nets and compared to those grown under unshaded control conditions. The ascorbic acid and pungency parameters were analyzed by high-performance liquid chromatographic methods. Ascorbic acid, a compound of high nutritive value in pepper, was highest in fruits gathered during the first summer harvest in both hybrids. The ascorbic acid content was found to be further increased in fruits from plants grown under white net shading in both 'Star Flame' and 'Fire Flame'. Total capsaicinoid contents in 'Star Flame' were influenced by the interaction of shading treatment and harvest time (p = 0.004), with the lowest amounts ($241.2-251.5mg{\cdot}kg^{-1}$ fresh weight) resulting from white and red shading treatments at the early autumn harvest. In 'Fire Flame', both shading treatment (p = 0.009) and harvest time (p < 0.001) affected total capsaicinoid contents. We observed significantly higher total capsaicinoid contents in control fruits compared to that resulting from red and green shading treatments at the second harvest, and that resulting from red shading treatment at the third harvest. Analysis of photosynthetic activity revealed a significant and negative correlation between Fv/Fm values and total capsaicinoid contents in both hybrids (p < 0.001). Based on the obtained results, the harvest of peppers during summer should be promoted to produce fruits with high pungency.

• Journal of Bio-Environment Control
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• v.15 no.3
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• pp.211-216
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• 2006

This study was carried out to investigate the effect of greenhouse cooling by a geothermal heat pump system on greenhouse temperature and growth of vegetable transplants in summer season. Greenhouse air temperature in day time was $3-4^{\circ}C$ lower in fog plus shading system than in shading, while in night time that was $5-7^{\circ}C$ lower in geothermal heat pump (GHP) plus shading system compared to shading or fogplus shading. system. Plant height of cucumber, tomato and hot pepper transplants was shortened in GHP plus shading compared to shading or fog plus shading system. And Leaf area and dry weight were slightly decreased in GHP plus shading compared to the other systems. Therefore, healthy transplant index on cucumber, tomato and hot pepper was higher in GHP plusshading than in shading or fogplusshading system.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.58 no.2
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• pp.158-163
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• 2009

A shading ring in an AC solenoid plays an important role in reducing vibration and humming sound. Estimation of performance of the shading ring placed in a stator pole of the AC solenoid is not an easy task due to the difficulty in measurement of the current and flux linkage of the shading ring. In this paper, dynamic performance of an AC solenoid with a shading ring is analyzed through the simulation using electromagnetic analysis software and the results are verified by simple AC and DC voltage tests. Both the simulation and experimental results show that the shading ring in the AC solenoid not only increases pull force, but also reduces operation time, vibration and humming sound.

• Proceedings of the IEEK Conference
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• 2002.06d
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• pp.199-202
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• 2002

This paper introduces the near field shading beamformer using widely known Chebyshev and Hanning window in the field of digital signal processing. The proposed shading beamformer improves the estimation of range as well as azimuth angle of targe residing in near field. A series of sensor weighting values are calculated from the FFT operation of given shading functions in time domain. This paper verifies the performance of the focused beamformer having the proposed shading sensor weights which are used to detect the range of target. Throughout computer simulations this paper exploits the performance improvement of the proposed shading beamformer as varying the frequency band of the received radiated signal along the non-uniform array.

• Journal of the Korean Institute of Landscape Architecture
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• v.19 no.4
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• pp.46-57
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• 1992

This study was carried out to compare physiological characteristics of winter green cultivar (Buxus microphylla van. koreana 'Hanlim') with those of native cultuvar and clucidate the effect of environmental factors such as light intensity, time of shading, and nutrients etc. on leaf color in Korean boxwood(Buxus microphylla var. koreana Nakai). The results are summarized as followed; The 'Hanlim' cultivar had higher contents of chlorophyll as compared with native cultivar from September, 1989 to March, 1990. However, at April, 1990, native cultivar had higher chlorophyll contents. In the rate of photosynthesis, 'Hanlim' cultivar was higher than native cultivar from September to December, 1989, but showed the opposite trend from March to April, 1990. As to the period of browning, 'Hanlim'cultivar had stayed green even after November 22, 1989, while the foliage of native cultivar turned yellowish brown color through the winter. The contents of nitrogen and potassium of 'Hanlim' cultivar werehigher than those of the native cultivar. However native cultivar had higher rate of phosphorus, magnessium, and calcium. In the effect of environmental factors such as light intensity, time of shading, and nutrients etc. on leaf color in Korean boxwood(Buxus microphylla var. koreana Nakai), chlorophyll contents were increased with shading and leaves grown 70% shading had twice as much as those of full sunlight, fertilized plot. Nutrient fertilization increased chlorophyll contents and values of color in boxwood too. In the shading times, early shading time maintained effectively green color of boxwood in winter. Therefore, in case of native cultivars, it has planted at full sunlight area until now and color of leaves turned yellowish brown color through the witner. However, it will maintain green color of leaves by planting at shade area. In addition to, as 'Hanlim' cultivar had benefits of maintain green color of leaves during winter, it will be planted at full sunlight area to landscape plants.

• Proceedings of the KIPE Conference
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• 2017.07a
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• pp.136-137
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• 2017

Maximum power point tracking (MPPT) under partial shading condition (PSC) is a challenging process in the PV array system. The shaded PV panel makes different peak patterns on the P-V curve and misguides the MPPT algorithm. Various kinds of global MPP (GMPP) detecting algorithms are used to overcome this issue. Generally, too frequent execution of GMPP tracking algorithm reduces the achievable power of PV panel due to time spent on the scanning process. Thus, partial shading detection algorithm is essential for efficient utilization of solar energy source. While conventional method only detects fast shading patterns, the proposed algorithm always shows superb performance regardless of the speed of partial shading patterns.

• Journal of Digital Contents Society
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• v.9 no.3
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• pp.509-516
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• 2008

We propose the Hybrid Rendering model to support multi-resolution for computer graphics. LOD method for computer graphics system considering performance of device environment and end-user preference usually adopts mesh resolution, mipmap in texture rendering, or oct-tree data structure in ray tracing. The hybrid rendering model, as a local shading model combining Gouraud shading model and a flat shading model, applies a proper shading method to each of polygons consisting of an object. This method can be an effective alternative to reduce real-time rendering time so that it can be utilized in real time adaptive service of computer graphic contents among various device environments under ubiquitous environments.

• Journal of Bio-Environment Control
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• v.12 no.1
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• pp.45-53
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• 2003

The object of this study was to develop the control technology of daily integral photosynthetic photon flux (PPF) by the artificial lighting and shading screen in greenhouse. The shading time needed to get the target PPF by using two types of shading screens having shading ratio of 55% and 85% was analyzed. The results showed the shading ratio of screen to be installed in greenhouse should be different depending on the amount of target PPF to be controlled. The PPF control experiment by using the 55% shading screen in July and August showed that the maximum difference between measured and calculated value was about 5 mol$.$ $m^{-2}$ $.$ $d^{-1}$ in no shading condition. This difference is satisfactory result because the daily integral PPF is quite different depending on the weather condition. The simulation result about PPF distribution pattern shortened the time needed to find the proper arrangement of artificial lightings in greenhouse. But the further study was required to find the supplemental lighting arrangement to be able to provide the exactly uniform distribution of target light intensity. The supplemental irradiation time needed to acquire the target daily integral PPF for different supplemental light intensities, weather conditions, and months was analyzed. The result showed that the supplemental light intensity should be decided depending on the amount of target PPF to be controlled. The result of PPF control experiment conducted by using 55% shading screen and 300 $\mu$mol$.$ $m^{-2}$ $.$ $s^{-1}$ supplemental light intensity from the end of May to the beginning of June showed that the maximum difference between target and measured value was about 3 mol$.$ $d^{-1}$ $.$ $m^{-2}$ . If we consider that the difference of the daily integral PPF depending on weather condition was the maximum 30 mol$.$ $m^{-2}$ $.$ $d^{-l}$, the control effect was acceptable. Although the result of this study was the PPF control technology to grow lettuce, the data and control method obtained could be employed for other crop production.n.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.16 no.8
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• pp.1759-1764
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• 2012

This paper describes FPGA design and realization using the shading correction algorithm for a CCD scan image enhancement. The shading algorithm is used by LUT (Look-up Table). The image enhancement results from that the histogram minimum value and maximum with respect to all pixels of the CCD image should be extracted, and the shading LUT is constructed to keep constant histogram with offset data. The output of sensor be converted to corrected LUT image in preprocessing, and the converting system is realized by FPGA to be enabled to operate in real time. The result of the experimentation for the proposed system is showed to take the scanning time 2.4ms below. The system is presented to be based on a low speed processor system to scan enhanced images in real time and be guaranteed to be low cost.