• Title/Summary/Keyword: natural light

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A Study on Lighting Performance Evaluation of Light-Shelf using Crystal Face (결정면 적용 광선반 채광성능 평가 연구)

  • Lee, Heangwoo;Rogers, Kyle Eric;Seo, Janghoo;Kim, Yongseong
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.27 no.8
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    • pp.395-401
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    • 2015
  • Recently, many research studies have been carried out on the efficiency of light-shelf daylighting systems, especially comparing performance improvements and the limitations of reflective surfaces and their lighting performance. In this study, a crystal face reflective surface is proposed. The objective of the study is to evaluate the lighting performance of a crystal face light-shelf through a performance study. The performance study was carried out in a full scale test-bed in order to calculate the light distribution and energy consumption utilizing the standard indoor illumination as an index. The conclusions of the performance study are as follows. 1) The optimal angle of incidence for daylighting for both the operable flat type light-shelf and the crystal face light-shelf are taken in the natural environment on the dates of the winter and summer solstices, as well as the autumn and spring equinoxes. 2) The application and installation of the crystal face light-shelf can produce a 29.9%~34.3% increase of light distribution within the indoor space. However, the increase of light distribution can also lead to a decrease in the uniformity ratio, a design challenge that should be considered when applying a crystal face light-shelf. 3) It is possible to achieve a 7.98%~13.3% greater reduction in energy consumption when applying a crystal face light-shelf than when applying a flat type light-shelf. The increase in the number of crystal faces should concur with the analysis of the energy reduction. A limitation of the study is that only one predetermined pattern was performance tested for a crystal face light-shelf. In order to carry out further research on crystal face light-shelves, additional performance studies are needed based on alternative patterns and designs.

The effect of rod domain A148V mutation of neurofilament light chain on filament formation

  • Lee, In-Bum;Kim, Sung-Kuk;Chung, Sang-Hee;Kim, Ho;Kwon, Taeg-Kyu;Min, Do-Sik;Chang, Jong-Soo
    • BMB Reports
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    • v.41 no.12
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    • pp.868-874
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    • 2008
  • Neurofilaments (NFs) are neuronal intermediate filaments composed of light (NF-L), middle (NF-M), and heavy (NF-H) subunits. NF-L self-assembles into a "core" filament with which NF-M or NF-H co-assembles to form the neuronal intermediate filament. Recent reports show that point mutations of the NF-L gene result in Charcot-Marie-Tooth disease (CMT). However, the most recently described rod domain mutant of human NF-L (A148V) has not been characterized in cellular level. We cloned human NF-L and used it to engineer the A148V. In phenotypic analysis using SW13 cells, A148V mutation completely abolished filament formation despite of presence of NF-M. Moreover, A148V mutation reduced the levels of in vitro self-assembly using GST-NF-L (H/R) fusion protein whereas control (A296T) mutant did not affect the filament formation. These results suggest that alanine at position 148 is essentially required for NF-L self-assembly leading to subsequent filament formation in neuronal cells.

Dyeing Properties of Young Superfluous Fruits of Naju Pear Trees (나주배 적과(摘果)중 유과(乳菓)의 염색성)

  • 이상필
    • The Korean Journal of Community Living Science
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    • v.15 no.1
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    • pp.27-33
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    • 2004
  • Natural dyeing means coloring with dyes extracted from plants, minerals or animals found in nature. Natural dyeing provides calm and natural colors; it has antibacterial and deodorizing qualities; and the dyeing process is environmentally friendly. This study extracted natural dyes from young fruit by thinning out the superfluous fruits of Naju pear trees, and then examined its dyeing properties, the optimal dyeing conditions, and its color fastness for practical use. The results indicated that dyeing is ideal when it had Cu mordant treatment (5% concentration at 9$0^{\circ}C$, pH 4) for 50 min. The color fastness of natural dyes with Cu mordant treatment was very excellent after rubbing and dry cleaning, and also good after exposure to perspiration, light and washing.

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A Preliminary Study on Natural Dyeing by the Delphi Method (Part III) -Developing Valuation of Natural Dyes- (델파이법을 이용한 천연염색에 관한 기초 연구 (제3보) -천연염료의 개발가치 평가-)

  • You Myung-Nim;Roh Eui-Kyung
    • Journal of the Korean Society of Clothing and Textiles
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    • v.30 no.5 s.153
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    • pp.733-741
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    • 2006
  • This study was to investigate categories of valuation and make the standard on developing valuation of natural dyes by Delphi method. The three-round Delphi tests were performed with 36 professional in the academic, the industrial, and the art field.'Dyeability property' meant levelling, adsorption, color diversity with mordant, color stability, 'marketability', possibility of mass production, economical efficiency, functionality, demand and supply of natural dyes, 'color', yield, beautiful color, value of color and 'color fastness', washing, perspiration and light fastness. Indigo, persimmon, cochineal, safflower and onion in dyeability property were evaluated highly, functional natural dyes in marketability, red and purple color ones except indigo in color and ones containing tannin in color fastness.

A Study on Psychological Effect of Natural Element in Rest Space of Office (오피스 휴게공간에서 자연요소의 심리적 효과에 관한 연구)

  • Kang, Min-Kyung;Lyu, Ho-Chang
    • Proceedings of the Korean Institute of Interior Design Conference
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    • 2004.11a
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    • pp.84-87
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    • 2004
  • The stress from the office environment comes from the most psychological things. Therefore, the purpose of this study is to research the psychological effect of natural element for office worker's psychological stability. This study is focused on the light, sound, air, temperature, plant, and water. Perception of these natural elements through the senses of sight, auditory, smell, and touch is effect on human body and mind directly. The application of natural elements provide a health of office workers. The result will show that, with application of the natural element, the rest space will be more powerful for health of workers. And also combination of natural element and geometric pattern will be very useful to prepare healing environment on the rest space

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Dyeing Fabrics with Grape Juice which is Discarded in the Process of Grape Juice (포도쥬스 제조중 폐기되는 포도액을 이용한 직물염색)

  • Jeong, Young-Ok;Kim, Soon-Sim
    • Fashion & Textile Research Journal
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    • v.4 no.1
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    • pp.79-85
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    • 2002
  • To develope natural dyeing materials from the unused plant materials, we had several dyeing experiments to investigate the optimum conditions of dyeing fabrics with the waste grape juice. Dyeing experiments were done under different dyeing conditions of dyeing time, dyeing temperature, pH and concentration of dyebath and mordants which were treated after dyeing. Experimental fabrics were silk, cotton, ramie and hemp. Color difference(${\Delta}E$) and Munsell's HV/C of the dyed fabrics and color fastness of silk dyed fabrics to dry cleaning, washing, rubbing, perspiration and light were measured. The color differences of dyed experimental fabrics were very slightly increased with dyeing time and the color of dyed silk was light purple and the cotton, ramie and hemp was light red purple. The color differences of dyed experimental fabrics were decreased and the color became lighter with dyeing temperature increased. The color differences of dyed experimental fabrics were decreased and the color changed from light purple to blue with the pH of dyebath increased. The color differences of dyed experimental fabrics were slightly increased with the concentration of dyebath increased. The color of dyed fabric changed with the mordant treatment and were different among the experimental fabrics. On the whole, blue tone increased with the Al and Fe mordant and green tone increased with the Cu mordant. The color fastness of dyed silk fabrics to light, washing (change) and perspiration (change) was bad and color fastness to dry cleaning and rubbing were good.

Structural Analysis and Light-Weight Design of Aircraft Floats with Laminated Composites (복합재 적층판을 이용한 경항공기 플로트 구조해석 및 경량화)

  • Choi, Youn-Gyu;Kim, Sung-Jun;Shin, Eui-Sup
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.25 no.1
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    • pp.65-71
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    • 2012
  • In order to improve the structural safety and light-weight design of aircraft floats, natural frequency and static stress analysis are performed under water and ground landing conditions. A finite element mesh based on the design configuration of light aircraft floats is modeled, and simplified water and ground landing loads are applied to this model. The natural frequency and stress analysis of aluminum-alloy floats are carried out first. Then, the structural performance of the floats is re-analyzed in the case of laminated composites, and the numerical results are compared each other. It is concluded that, by tailoring the laminated composites with respect to stacking sequence and ply thickness, the structural safety of the light-weight floats can be improved.

Studies on the improvement of UV sterilizer for toothbrush (가정용 칫솔 UV 살균기의 성능 개선법에 관한 연구)

  • Yang, Eun-Jung;Lee, Mi-Seon;Kim, Jung-Woo
    • The Journal of Natural Sciences
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    • v.11 no.1
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    • pp.41-44
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    • 1999
  • For the purpose of improving the UV sterilization for toothbrush, the sterilizing effects by the UV light were studied. When toothbrushes were treated with the UV light for 5, 15, 30, 60 minutes, the sufficient antibacterial effect were shown after 15 minutes with 80% of bactericidal effects. To prevent the brownish stain on the sterilizer which was caused by the long exposure of UV light, no UV treatment for two hours after 15 minutes exposure were scheduled and then 3 minutes re-exposure were performed, which showed 97% of bactericidal effect. Also, the antibacterial effects of the sterilizer showed different results depending on the position of the toothbrush, it was recommended to adjust toothbrush to be exposed by the UV light directly.

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Feasibility Study of Non Local Means Noise Reduction Algorithm with Improved Time Resolution in Light Microscopic Image (광학 현미경 영상 기반 시간 분해능이 향상된 비지역적 평균 노이즈 제거 알고리즘 가능성 연구)

  • Lee, Youngjin;Kim, Ji-Youn
    • Journal of the Korean Society of Radiology
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    • v.13 no.4
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    • pp.623-628
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    • 2019
  • The aim of this study was to design fast non local means (FNLM) noise reduction algorithm and to confirm its application feasibility in light microscopic image. For that aim, we acquired mouse first molar image and compared between previous widely used noise reduction algorithm and our proposed FNLM algorithm in acquired light microscopic image. Contrast to noise ratio, coefficient of variation, and no reference-based evaluation parameter such as natural image quality evaluator (NIQE) and blind/referenceless image spatial quality evaluator (BRISQUE) were used in this study. According to the result, our proposed FNLM noise reduction algorithm can achieve excellent result in all evaluation parameters. In particular, it was confirmed that the NIQE and BRISQUE evaluation parameters for analyzing the overall morphologcal image of the tooth were 1.14 and 1.12 times better than the original image, respectively. In conclusion, we demonstrated the usefulness and feasibility of FNLM noise reduction algorithm in light microscopic image of small animal tooth.

Environmental Control in the Plant Factory System Influences Year-Round Production of Allium hookeri Leaves (삼채(Allium hookeri) 잎 연중생산을 위한 식물공장 환경제어 효과)

  • Jeong-Wook Heo;Jeong-Hyun Baek;Sung-Hyen Lee;Min-Jeong Kim;Chang-Kee Shim
    • Korean Journal of Environmental Agriculture
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    • v.42 no.4
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    • pp.279-285
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    • 2023
  • The demand for the fresh leaf of hooker chive, which is mainly used as functional roots and contains dietary sulfur or saponin, is increasing, but the leaves are only harvested 3-4 times per year under conventional field conditions. A plant factory system with different light qualities or intensities was applied for year-round production of the fresh leaves. Hooker chive (Allium hookeri) roots were hydroponically cultured under the plant factory with a mixture of blue plus red LEDs (Light-Emitting Diodes) and fluorescent lights for 50 weeks. Maximum leaf growth was attained with the 1.5 dS/m EC in the culture medium under the plant factory. The average leaf and shoot numbers of hooker chive grown hydroponically under a mixture of 200 µmol/m2/s LEDs increased by 147% and 140%, respectively compared to those under 100 µmol/m2/s LEDs at the 10th harvest. The leaf length of hooker chive grown under the LEDs treatment with the lowest light intensity significantly increased by 27% compared with the natural light treatment at the 10th harvest. However, there was no significant difference in leaf pigmentation between natural and 200 µmol/m2/s LEDs treatments. Plant factory with the mixture LEDs of blue and red lights can be applied for year-round production of hooker chive fresh leaves to ensure a stable supply of leafy vegetable throughout the year.