• Title/Summary/Keyword: Clearness

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Statistical Study and Prediction of Variability of Erythemal Ultraviolet Irradiance Solar Values in Valencia, Spain

  • Gurrea, Gonzalo;Blanca-Gimenez, Vicente;Perez, Vicente;Serrano, Maria-Antonia;Moreno, Juan-Carlos
    • Asia-Pacific Journal of Atmospheric Sciences
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    • v.54 no.4
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    • pp.599-610
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    • 2018
  • The goal of this study was to statistically analyse the variability of global irradiance and ultraviolet erythemal (UVER) irradiance and their interrelationships with global and UVER irradiance, global clearness indices and ozone. A prediction of short-term UVER solar irradiance values was also obtained. Extreme values of UVER irradiance were included in the data set, as well as a time series of ultraviolet irradiance variability (UIV). The study period was from 2005 to 2014 and approximately 250,000 readings were taken at 5-min intervals. The effect of the clearness indices on global irradiance variability (GIV) and UIV was also recorded and bi-dimensional distributions were used to gather information on the two measured variables. With regard to daily GIV and UIV, it is also shown that for global clearness index ($k_t$) values lower than 0.6 both global and UVER irradiance had greater variability and that UIVon cloud-free days ($k_t$ higher than 0.65) exceeds GIV. To study the dependence between UIVand GIV the ${\chi}^2$ statistical method was used. It can be concluded that there is a 95% probability of a clear dependency between the variabilities. A connection between high $k_t$ (corresponding to cloudless days) and low variabilities was found in the analysis of bidimensional distributions. Extreme values of UVER irradiance were also analyzed and it was possible to calculate the probable future values of UVER irradiance by extrapolating the values of the adjustment curve obtained from the Gumbel distribution.

Physical factors Affecting Sound Sensation for Korean Traditional Silk Fabrics with Similar Sound Pressure Levels (유사 음압 전통 견직물의 소리 감각에 영향을 미치는 물리적 요인)

  • Cho Su-Min;Cho Gil-Soo;Yi Eun-Jou
    • Science of Emotion and Sensibility
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    • v.9 no.1
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    • pp.39-48
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    • 2006
  • This study was carried out to investigate sound sensation of Korean traditional silk fabrics with similar sound pressure levels (SPL) and to identify secondary physical factors excluding SPL which determine sound sensation of the fabrics. Sounds of the silk fabrics tended to be perceived differently from one another as for some of sensation such as clearness ant roughness. They were felt more strongly in aspects of loudness, roughness, and highness than of softness, sharpness, clearness, and pleasantness. Subjective clearness, roughness, and highness were significantly correlated with some of sound parameters including roughness(z), ${\Delta}L,\;and\;{\Delta}f$. Especially, both of clearness and roughness which were varied among the fabrics were found as determined by ${\Delta}L$. This result means that ${\Delta}L$ as well as roughness(z) and ${\Delta}f$ could be utilized secondary to SPL in order to satisfy some of human sensibility for sound from traditional silk fabrics without variation of physical loudness.

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A Study on the characteristic a reflector of retaining wall by PV module (PV module을 이용한 옹벽용 반사판 특성에 관한 연구)

  • 김대근
    • Proceedings of the KIPE Conference
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    • 2000.07a
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    • pp.41-44
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    • 2000
  • This paper represent about design of the controller for battery of a reflector of retaining wall for power supply using PV Module. Simulation is represents V-I and power characteristic by Mathematica & Design Cneter 6.3 & Qnet 2.1 Finally we composed of road surface-signpost system. This system is successfully operating with high clearness lights.

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A Comparative Study of Eastern and Western Cross-Style in Modern Fashion - Through a Comparative Study of "West Meets East" vs. "East Meets West" - (현대 패션에 나타난 동.서양 Cross-Style 비교 연구 - 동.서양 사유관의 비교 연구를 통하여 -)

  • Chae, Hye-Sook;Chae, Keum-Suk
    • Journal of the Korean Society of Costume
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    • v.58 no.10
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    • pp.95-111
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    • 2008
  • Now when Wests meet Easts, they approach with a motive of acknowledging Eastern or Asian value, concretizing and sharing philosophy. As the result of this study through comparing Eastern and Western view of thinking, First, East is the cosmic beauty of harmony that pursues the harmony with the nature involving emotional and humane affection, and West has the tendency of proportional beauty of harmony involving order and balance. Second, East pursues the metaphorical beauty of mimesis which implies more in invisible parts, and West has the tendency of pursuing visual beauty of mimesis which has contents in visible parts. Third, East is the sublime beauty of nothingness which suggests a blank is endless infinitude of doctrines and mind breath, and West pursues the sublime beauty of being which desires to fill tangible existence without blank. Fourth, East is the expressive beauty that has the intuition of pleasure, which gives weight on non-clearness, emotional joke, and satire, and emphasizes a comic phase, and in West pursuing clearness of order, the concept of the ugliness of disformation is the intuition of defiance, and close to intuition of sadness.

Sound Characteristics and Hand of Fabrics for Blouse (블라우스용 직물의 소리 특성과 태)

  • 이은주;조길수
    • Journal of the Korean Society of Clothing and Textiles
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    • v.24 no.4
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    • pp.605-615
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    • 2000
  • This study was carried out to investigate sound characteristics including sound parameters and subjective sensation, and primary hand values related with sound of fabrics for blouse, and furthermore to predict subjective sound sensation with mechanical properties and sound parameters. Sound of specimens was analyzed by FFT. Level pressure of total sound(LPT), loudness(Z), coefficients of autoregressive(AR) functions for fitting the spectra, and sound color factors(ΔL and Δf) were obtained as sound parameters. Primary hand values for women's thin dress were calculated by using KES-FB. Subjective sensation for sound including softness, loudness, sharpness, clearness, roughness, highness, and pleasantness was evaluated by free modulus magnitude estimation. The results were as follows; 1. Fabrics for blouse showed similar spectral shapes to one another in that amplitude values were lower in most ranges of frequencies than fabrics for other uses. 2. It was found that fabrics for blouse were less louder because LPT, loudness(Z), and ARC values were lower than other fabrics. 3. Primary hand values indicated that specimens were soft-touched, flexible, and less crisp. Among primary hands related with sound, Shari values were higher for silk fabrics than for synthetic ones, while the values for Kishimi were similar, 4. Fabrics for blouse were rated more highly for softness, clearness, and pleasantness than for loudness, sharpness. roughness, and highness. Silk fabrics were evaluated more pleasant than synthetic fabrics. 5. Subjective sensation for sound of blouse fabrics were predicted with mechanical properties and physical sound parameters.

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Analysis of X-ray image Qualities -accuracy of shape and clearness of image using X-ray digital tomosynthesis (디지털 영상 합성에 의한 X선 단층 영상의 형상 정확도와 선명도 분석)

  • Roh, Yeong-Jun;Cho, Hyung-Suck;Kim, Hyeong-Cheol;Kim, Sung-Kwon
    • Journal of Institute of Control, Robotics and Systems
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    • v.5 no.5
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    • pp.558-567
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    • 1999
  • X-ray laminography and DT(digital tomosynthesis) that can form a cross-sectional image of 3-D objects promis to be good solutions for inspecting interior defects of industrial products. DT is a kind of laminography technique and the difference is in the fact that it synthesizes the several projected images by use of the digitized memory and computation. The quality of images acquired from the DT system varies according to image synthesizing methods, the number of images used in image synthesizing, and X-ray projection angles. In this paper, a new image synthesizing method named 'log-root method' is proposed to get clear and accurate cross-sectional images, which can reduce both artifact and blurring generated by materials out of focal plane. To evaluate the quality of cross-sectional images, two evaluating criteria : (1) shape accuracy and (2) clearness of the cross-sectional images are defined. Based on these criteria, a series of simulations are performed, and the results show the superiority of the new synthesizing method over the existing ones such as averaging and minimum methods.

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A Study on Image of Patterns [ 1 ] - With a focus on Development on Image Positioning of Patterns - (문양 이미지에 관한 연구[ 1 ] -문양 이미지 포지셔닝 기준 개발을 중심으로-)

  • Ryu, Hyun-Jung;Kim, Min-Ja
    • Journal of the Korean Society of Costume
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    • v.59 no.2
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    • pp.29-41
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    • 2009
  • Perception between real object and recognized subject of human on objective subject is not the same. The reason Is that individual perception of visual design components are transmitted as the image of whole. It is required process of visual perception. Therefore, I developed the vision of seeing image of pattern which is based on Gestalt visual perception theory in clothes. The summary of this study's results is like followings. Extremely antagonistic terms which are specialized by formative characteristics of formative components are clearness and blur of outline/ fixed shape and non-fixed shape/ visuality and tangibility of representation/ simplicity and complexity of structure/ invariability and variability of mobility/ symmetry and asymmetry of arrangements singularity and plurality of group number. The expression of motive shows that clearness, fixed shape, visuality and simplicity pursuit Determination image, and blur, non-fixed shape, tangibility and complexity pursuit Ambiguity image. The arrangements of motive shows that invariability, symmetry and singularity pursuit Order image, and variability asymmetry and plurality pursuit Disorder image. Therefore, the standard of the coordinator of Pattern image positioning is established as Determination and Ambiguity of motive are X-axis, and Order and Disorder of pattern are Y-axis. As the frame of Pattern image positioning, four separated dimensions have made.

Dynamic performance analysis of flat plate solar collector system according to weather conditions and capacity of heat storage tank (기상조건과 축열조 용량에 따른 평판형 태양열 집열기 시스템의 동적 성능 해석)

  • Park, Bae-Duck;Kim, Gew-Deok;Kim, Kyoung-Hoon
    • Journal of the Korean Solar Energy Society
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    • v.34 no.6
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    • pp.57-65
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    • 2014
  • Solar energy has attracted wide attention as a promising renewable energy source. The goal of this paper is to estimate the dynamic performance of solar flat plate collector system according to the weather conditions and the capacity of heat storage tank. This study provides a detailed description of the modeling methods and materials of the system. The effects of the daily clearness index and the volume of the heat storage tank on the hourly and daily performances of the system are numerically investigated. Special attention is focused on the important system variables including the solar insolation on the collector surface, useful energy, heat loss at the collector, and collector efficiency.

Beam and Diffuse to Global Solar Irradiation Correlation Coefficients for Daejeon (대전지역 직달 및 산란과 전일사 상관계수)

  • Lee, Kwan-Ho;Song, Doo-Sam
    • Journal of the Korean Solar Energy Society
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    • v.39 no.4
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    • pp.11-24
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    • 2019
  • The total solar irradiation on horizontal surfaces is separated into the beam and diffuses components. Although horizontal global irradiance is a commonly measured parameter for many sites, horizontal diffuse irradiance is not so readily obtainable. For such sites that measure global irradiation alone, a simple but reasonably accurate method is required to estimate diffuse irradiance from its global counterpart. This study investigates the applicability of correlation coefficients models correlating hourly diffuse and beam fraction and hourly clearness index in Daejeon. The three diffuse to global correlation coefficients models (Orgill and Holland model, CIBSE Guide J model, and Erbs et al. model) are selected and the three modified beam to global correlation coefficients models are generated. MBE, RMSE, r-squared of Daejeon and Daejeon boundary site-fitted models are compared with the case of original coefficients. The comparison result shows that the beam and diffuse to global solar irradiation correlation coefficients models with boundary site-fitted coefficients are best suitable for Daejeon. Further researches will be conducted to find the boundary site-fitting method using measured data of other cities and correlation coefficients models using solar altitude, cloud cover, and sunshine duration.

Effects of Fining Treatments on Color and Clearness of Apple Wine (청징방법에 따른 사과와인의 색과 투명도에 미치는 영향)

  • Bang, Byung-Ho;Jeong, Eun-Ja;Kang, Hyeran;Rhee, Moon-Soo;Yi, Dong-Heui;Paik, Jean Kyung
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.46 no.3
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    • pp.368-373
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    • 2017
  • Comparative fining trials were conducted in a laboratory to study the effects of fining treatments including polyvinylpolypyrrolidone (PVPP) and bentonite on the color and clearness of apple wine. The wines were subjected to three different fining treatments: PVPP, PVPP+bentonite (applied at the same time), and PVPP+bentonite (24 h later). Based on the results, all treatments induced noticeable decreases in wine color (APHA value) and turbidity. The treatment including PVPP and bentonite at the same time provided the best results in relation to wine color and clearness. PVPP was the most effective in the reduction of phenolic compounds, which means it helped wine obtain a paler color. Organic acids and aromatic profile were not altered by the fining treatments.