• Title/Summary/Keyword: Clearness Number

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Generation of monthly averaged horizontal Radiation based on a regional clearness estimating model (우리나라 지역별 청명도 예측 모델을 이용한 월평균 수평면 일사량 산출)

  • Kim, Jin-Hyo;Kim, Min-Hwi;Kwon, Oh-Hyun;Seok, Yoon-Jin;Jeong, Jae-Weon
    • Journal of the Korean Solar Energy Society
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    • v.30 no.2
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    • pp.72-80
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    • 2010
  • The main thrust of this paper is to investigate a practical way of generating the monthly averaged daily horizontal solar radiation in Korea. For estimating the horizontal solar radiation, the clearness index($K_T$) and the clearness number($C_N$) which are required for the use of Liu and Jordan's model and ASHRAE Clear Sky model were derived based on the measured weather data. Third-order polynomials returning $K_T$ and��$C_N$ for a given location were derived as a function of cloud amount, month, date, latitude and longitude. The predicted monthly averaged daily horizontal solar radiation values were compared with those acquired from the established design weather data. The MBE(Mean Bias Error) and RMSE (Root Mean Squares for Error) between the predicted values and the measured data were near zero. It means that the suggested third-order polynomials for $K_T$ and $C_N$ have good applicability to Liu and Jordan's model and ASHRAE Clear Sky model.

A Study on the Classification Scheme of the Internet Search Engine (인터넷 탐색엔진에 관한 연구)

  • 김영보
    • Journal of the Korean BIBLIA Society for library and Information Science
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    • v.8 no.1
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    • pp.197-227
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    • 1997
  • The main purpose of this study is ① to settle and to analyze the classification of the Internet Search Engine comparitively, and ② to build the compatible model of Internet Search Engine classification in order to seek information on the Internet resources. specially in the branch of the Computers and Internet areas. For this study, four Internet Search Engine (Excite, 1-Detect, Simmany, Yahoo Korea!), Inspec Classification and two distionaries were used. The major findings and result of analysis are summarized as follows : 1. The basis of the classification is the scope of topics, the system logic, the clearness, the efficiency. 2. The scope of topics is analyzed comparitively by the number of items from each Search Engine. In the result, Excite is the most superior of the four 3. The system logic is analyzed comparitively by the casuality balance and consistency of the items from each Search Engine. In the result, Excite is the most superior of the four 4. The clearness is analyzed comparitively by the clearness and accuracy of items, the recognition of the searchers. In the result, Excite is the most superior of the four. 5 The efficiency is analyzed comparitively by the exactness of indexing and decreasing the effort of the searchers. In the result, Yahoo Korea! is the most superior of the four. 6 The compatible model of Internet Search Engine classification is estavlished to uplift the scope of topics, the system logic, the clearness, and the efficiency. The model divides the area mainly based upon the topics and resources using‘bookmark’and‘shadow’concept.

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Studies on the Selection Efficiency for Clear Rice in the wx - carrier technique. (wx-Carrier Technique를 이용한 맑은 쌀의 선발에 관한 연구)

  • Heu, M.H.;Kim, H.Y.
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.29 no.1
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    • pp.1-10
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    • 1984
  • The main objective of this experiment was to investigate the selection efficiency for clear rice by the application of the wx-carrier technique in rice. Twelve semi-dwarf waxy lines were bred through backcrosses to the two recurrent semi-dwarf parents, IR667 and IR1317, utilizing six different waxy cultivars as waxy donor parent. These waxy lines were crossed to three clear non-waxy varieties, IR24, Suweon 287 and Suweon294. Their F$_3$ seeds were separated into waxy and non-waxy and the clearness of non-waxy grains were counted. The results are summarized as follows: l. Mean clearness per plant for twelve waxy lines ranged from 3.7% to 78.9% at the 35 days after heading. It was higher in the lines which utilized IR 1317 as recurrent parent and it was lower in the lines which utilized IR667 as recurrent parent. Mean clearness per plant for recurrent parent, IRl317 and IR667 were 47.6% and 5.6% respectively. The clear non-waxy parents; Suweon287, IR24 and Suweon294 showed 83.7% 80.5% and 73.5% clearness respectively. 2. Mean clearness of F$_3$ seeds of the crosses between different waxy parents and IR24, Suweon 294 and Suweon 287 ranged 16.7-73.9%, 21.9-42.9% and 10.6-26.9%, respectively. IR24 crosses showed the highest mean clearness. 3. Highly positive correlation was found between the clearness of F$_3$ seeds of Suweon 287 crosses and those of Suweon294. 4. Significant differences were observed in mean clearness of F$_3$ seeds of the crosses between the different waxy lines, which was bred through the same number of backcrosses to the same recurrent parent, and a clear non-waxy parent. Crosses of IR1317 recurrent parent showed higher mean clearness than those of IR667 recurrent parent. 5. In some crosses, clearness was higher in homo-non-waxy than in hetero-non-waxy, but, in other crosses it was higher in hetero-non-waxy. Thus no distinct pattern in the segregation of clearness was observed along the homo-non-waxy or hetero-non-waxy. 6. From the results it was concluded that, the selection efficiency for the clear rice can be improved by choosing the proper waxy parent, as well as proper recurrent parent under the wx-carrier technique.

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Analysis of X-ray image qualities-accuracy of shape and clearness of image-using X-ray digital tomosynthesis

  • Roh, Young Jun;Kang, Sung Taek;Kim, Hyung Cheol;Kim, Sung-Kwon
    • 제어로봇시스템학회:학술대회논문집
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    • 1997.10a
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    • pp.572-576
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    • 1997
  • X-ray laminography and DT(digital tomosynthesis) that can form a cross-sectional image of 3-D objects promise to be good solutions for inspecting interior defects of industrial products. The major factors of the digital tomosynthesis that influence on the quality of x-ray cross-sectional images are also discussed. 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 in the cross-sectional image are defined. Based on this criteria, a series of simulations were performed, and the results show the superiority of the new synthesizing method over the existing ones such as averaging and minimum method.

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The ecological studies on Aspergillus kawachii Kitahara. (백국균 Aspergillus kawachii Kitahara의 생태학적 연구)

  • 이두영
    • Korean Journal of Microbiology
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    • v.6 no.4
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    • pp.113-121
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    • 1968
  • This study has been aimed to determine the ecological factors with relationship to the Jongkok production in view of fermentation technology by means of some strains, Asp. kawachii, which is now preserved by the author and the following factors are included during the study; inorganic salts, nitrogen, sugar, water contents and temperature. The results, are as follows: (a) Sugar among other above-mentioned factors is increasingly affecting the number of the short type of conidiophore on culture medium and the conidiophore is increased by direct ratio until glucose concentration of 50%, at which concentration is mostly effective for the short type of conidiophore, while other factors did not affect on it. (b) Until glucose concentration of 50% sugar component of culture medium is favorable for the spore formation of Asp. kawachii by direct ratio. And peptone or asparagine on nitrogen medium, calcium-phosphate among other inorganic salts, wheat bran and rice branare also favorable, but other factors rientioned earlier show no relationship with the spore formation. Sugar, however, also related with the spore color clearness of crimson and light brown, and spore color is mostly clear at the point of glucose concentration until 50%. And asparagine on nitrogen medium, calcium phosphate among other inorganic salts, rice bran did all affect on the color clearness, while other factors did not concern with color clearness. (c) Water, sugar and temperature have related with the acid formation which is promoted, by direct ratio at the point of water-saturated condition and glucose concentration of 50%, while temperature at $25^{\circ}C$favorably affected on the acid formation which is increased by inverse ratio at the temperature$25^{\circ}C$ to $45^{\circ}C$ And pH did not relate with the acid formation. (d) Cylindrical plate method devised by the author is mostly favorable for the preservation and isolation of culture, compared with the traditional slant medium method.

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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.

Comparisons of Diesel and DME Fuel in Macroscopic Spray Characteristics (디젤 및 DME 연료의 거시적 분무특성 비교)

  • Park, Junkyu;Chon, Munsoo;Park, Sungwook
    • Journal of ILASS-Korea
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    • v.17 no.4
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    • pp.205-209
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    • 2012
  • This study focused on comparing macroscopic characteristics of DME and diesel fuel experimentally. DME fuel is one of the most promising alternative fuels because of its superiority in atomization characteristic and clearness in terms of exhaust gas compared with existing fossil fuels. In addition, DME fuel has high cetane number so it could be applied to compression ignition engine. However because DME fuel exists in gas phase at room temperature and atmospheric pressure, and it corrodes rubber parts of fuel line, DME fuel is hard to apply to commercial vehicles. To establish knowledge about DME fuel and furthermore, to develop commercial DME vehicles such as passenger cars, many research have been proceeded steadily. The present study, by comparing spray characteristics of DME fuel to those of diesel fuel, improved atomization characteristics in DME were revealed. Injection quantity measurement and spray visualization experiment were progressed and it was revealed that DME fuel shows small injection quantity than that of diesel fuel and axial development of spray in terms of spray tip penetration decreases when DME fuel was injected.

A research on Safety and Dangerous Awareness of Environment on Walking trails (도보길환경의 안전 및 위험인식에 관한 조사연구)

  • Kim, Young-duk;Byun, Kyeonghwa
    • Journal of the Korean Institute of Rural Architecture
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    • v.20 no.1
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    • pp.45-52
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    • 2018
  • The purpose of this study is to investigate safety and dangerous awareness of environment on walking trails. For this purpose, questionnaire survey are carried out by people who had experience using walking trails during 2016. It is evaluated that environments of walking trails located inside big cities are inferior than ones located in small and medium-sized cities and countryside in air pollution, bed smell, water pollution, noise, and waste. Needs about management and number installed public restroom are high for hygienic environment of walking trails. With waste treatment, users of 2.4 percentage are showed improper behavior that they left their rubbish at the place out of view but others bring their trash. Accident likelihood is highly appreciated and possibility of physical accident like slipping is showed at the highest. The reasons of accident on walking trails are responded with carelessness of walkers and improper of installation or management of safety facility at the most. For safety environment of walking trails, needs of installation of safety fences and notices of dangerous area are requested. In order to separate prevention from paths of walking trails, signposts are needed at visual clearness, maintenance, installation with proper interval and location, and correct contents. Respondents of 2.4 percentage have experiences of accident on walking trails and physical accident like slipping is occurred at the most.

Search for the Efficient Hierarchical Data Structure in Mobile Screen (모바일 화면에서의 효율적인 메뉴구조 - 유목의 명확성, 깊이수준, 아이템의 수, 공간단서를 중심으로)

  • Cho, Kyung-Ja;Choi, Hyang;Han, Kwang-Hee
    • Korean Journal of Cognitive Science
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    • v.18 no.2
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    • pp.193-221
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    • 2007
  • This study explored the efficient hierarchical data structure of mobile interfaces. The first experiment demonstrated the effects of grouping(clear/unclear), depth level(2/3/5), and the number of items(32/64/128) on the search time and the number of errors. The results indicated that participants spent less time and made fewer errors to perform the task when the clear mobile interfaces, low depth level, and fewer items were provided. In addition, the results indicated that there were no effects of the depth level and the number of items on the search time and number of errors in clear mobile interfaces conditions. As depth level and the number of items changed, on the other hand, participants spent longer time to complete the task and made more mistakes in unclear mobile interfaces conditions. The second experiment investigated the effects of grouping(clear/unclear), the number of items(32/64/128), and spacial cues(colors/ windows/ number of cues) on search time and the number of errors in hierarchical data structures which had five depth levels. The results indicated that participants spent less time to complete the task and made less errors in a mobile interface when grouping is clear and the number of items are fewer. The results were identical with the first experiments. In addition, the main effect of spacial cues indicated that providing spacial cues via pictures and numbers can be helpful to reduce errors in search behaviors.

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