• Title/Summary/Keyword: Fans

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The Study of Alluvial Fans in Korea (한국(韓國) 선상지(扇狀地) 연구(硏究))

  • Park, No-Sik
    • Journal of the Speleological Society of Korea
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    • no.68
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    • pp.5-22
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    • 2005
  • Since earlier in 1947 the writer had been devoting part of his time to study alluvial fans in Korea based on his own interest in geomorphology. However, it was in 1958 when a new geography department was set up and the Research Center of National Lands was established in the university of Kyung Hee, the writer started scientific investigation for alluvial fans. The Following alluvial fans have been studied by the writer: those of Mt. Kwanak and Mt. Chungge in 1947; those of Pulkuksa in 1948; those of Suhnamsa, Suh Myun, Pusan in 1950; those of Shindonae, Mt. Kerrong, in summer of 1958; those of Hwaomsa, Kure and Yongsan Myun, Changhung, in winter of 1958. The article is the comparative study of the above mentioned alluvial fans including Suhkwangsa Fan, Chugaryng Rift Valley. Of course this is not the study covering all af alluvial fans in Korea. Within the limits of his surbey, the writer has com to a conclusion which may be helpful for the Korean alluvial fm study. 1. Korean alluvial fans are generally found in rift valleys or basins. 2. They are formed in places of below 220-meter contour line. 3. The slope from fna apex to river valley is 20-40 degree. The slope of fan surface is 5-20 degree, but most of them under 16 degree. A sudden change of slope is taken place or the fan apex and fan center. 4. Hills (100-200m) are developed on the surfaces of alluvial fans. 5. Most of rivers in alluvial fans are geyser rivers. 6. The depth of well : from ground surface to the well water surface is 4-8 m; water depth is 1-2m. 7. Land utilization; cultivated land 30%: non cultivatedland 70%. The area occupied by upland fields is twice of paddy field area. 8. Settlement : agglomerated settlement is developed on the top or the end of fan and surrounded by windbreakers. 9. Farming pattern at the top of fan fields are rectangular and parallel to flumes but at the center of fan, they are irregular and perpendicular to flumes.

Prediction of the Effect of Cooling Fan Electrification on City Bus (냉각팬 전동화에 따른 시내버스 연비효과 예측)

  • Lee, Yongkyu;Park, Jinil;Lee, Jonghwa
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.22 no.6
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    • pp.908-912
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    • 2013
  • Because of their longer operating times and larger size relative to conventional fans, the cooling fans mounted in buses consume larger amounts of energy. Most of the cooling fans mounted in a bus are connected to the engine by a viscous clutch. A viscous cooling fan's speed is determined by its fluid temperature, which is affected by the air flow through the radiator. The fan does not react immediately to the coolant temperature and in doing so causes unnecessary energy consumption. Therefore, the fuel economy of buses using viscous fans can be improved by changing to an electric cooling fan design, which can be actively controlled. In addition, electric power consumption is increased by using electric cooling fans. Thus, when electric fans are applied in conjunction with the alternator management system (AMS), the fuel economy is further enhanced. In this study, simulations were performed to predict coolant temperature and cooling fan speeds. Simulations were performed for both viscous and electric cooling fans, and power consumption was calculated. Additionally, fuel economy was calculated applying both the alternator management system and the electric cooling fan.

The Survey of Fire Hazard of Fan in Manufacturing Industries (제조 사업장의 환풍기 화재위험성 조사)

  • Kim, Sung-Sam
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.27 no.10
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    • pp.21-29
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    • 2013
  • The short circuit and overload is presented by main cause of electrical fire. However, 85% of the fan directly connected the outlet box without switch in total 110 fans as a research in manufacturing industries. In installation direction of vertical type fans which was placed on the horizontal surface, only 39 vertical type fans were placed on vertical surface and 71 fans were placed on the horizontal type. The installation direction of the fans warns of the risk of the fire hazard due to the motor stall to the user manual of the maker. However, it is the representative nonconformity example of construction which the people or builder disregards. In addition, the condition of ground connection with the earth leakage prevention was investigated in grounding of 5 fans, non-grounding of 105 fans. The double insulation structure is generally used for small fan and it can't connect ground wire as electric plug of non-grounding type. However, industrial iron fan needs ground wire for electric leakage and to protect against electric shock.

A Numerical Analysis and Experiment for Micro-Fans (축류 마이크로 홴의 전산해석 및 성능시험)

  • Cho, Jin-Soo;Pyun, Tae-Kyoon;Park, Wang-Sik;Chun, Chang-Kun
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.24 no.7
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    • pp.895-906
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    • 2000
  • A three dimensional linear frequency-domain lifting surface panel method was used for the aerodynamic analysis of axial flow type micro-fans. As proven by the duct modeling, the tip clearance of the micro-fans tested is large enough to ignore the calculated effect of the duct system. As the numerical results and experimental data agreed well in the operating point region, the method was applicable in the parametric studies to determine the design parameters of axial flow fans. Experiments on micro-fans were carried out based on KS B 6311. The newly designed micro-fan showed improvements in both static pressure rise and volumetric flow rate compared to the existing fans at a given operating condition. No detection of surging and the smooth characteristic curve proved the improvement in performance. To reduce the fan noise in the fan design, it was necessary to make use of the frequency spectrum analysis data. Measurement of sound pressure level for micro-fans was conducted based on KS B 6361 and KS A 0705. The peak - which occurs at blade passage frequency and its higher harmonics due to the fan noise - was not detected. This justifies the design methodology of the blade.

Theoretical Review and Experiment on Applicability of Double Skin Facade Ventilated by Fans (팬을 부착한 이중외피의 이론적 검토 및 적용성에 대한 실험 연구)

  • Lim, Ji-Hye;Sohn, Jang-Yeul
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.22 no.9
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    • pp.605-613
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    • 2010
  • Double skin facade(DSF) ventilated by fans consists of a normal external and an internal envelope. In this glass layer, the installed fan replaces an air inlet for the control of air flow through the cavity. The purpose of this paper is to investigate physical theory and to analyze the applicability of fans installed in a DSF. The experiment was conducted in 2 rooms. One room has a DSF with installed fans and the other one has a typical window. The room ventilated through a DSF which fans are installed was always kept warmer than the other room, ventilated directly from the outdoors. The average increase of the supplied air temperature through the DSF ventilated by fans was $6.54^{\circ}C$ at 78CMH, $6.2^{\circ}C$ at 95CMH, and $3.7^{\circ}C$ at 120CMH. As a result, the DSF with installed fans was appropriate for installation in rooms. It supplies outdoor fresh air heated through a cavity and ventilates a constant air volume.

A NOTE ON GRÖBNER FANS OF IDEALS

  • KIM, YONGGU
    • Honam Mathematical Journal
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    • v.21 no.1
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    • pp.19-33
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    • 1999
  • In this paper we reproduce results on $Gr{\ddot{o}}bner$ fans of ideals following a paper by T. Mora and L. Robbiano [5], and introduce stable $Gr{\ddot{o}}bner$ fans of ideals introduced by D. Mall [4]. We make minor corrections for the clarification, simplify proofs and provide new proofs. At the end we give a description of $Gr{\ddot{o}}bner$ fans of toric ideals.

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Understanding the Korean Fandom of the K-pop Focusing on Its Perspectives on Foreign Fans (케이팝(K-pop)의 한국 팬덤에 대한 연구 해외 팬들에 대한 인식을 중심으로)

  • Berbiguier, Mathieu;Cho, Younghan
    • Korean journal of communication and information
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    • v.81
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    • pp.272-298
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    • 2017
  • This study aims at understanding Korean fans who are also one of the most inquisitive consumers of the Korean pop products. For this purpose, it examines how Korean fandom perceives the procedures of the K-pop's globalization and constructs different perspectives of foreign fans. Firstly, it examines Korean fandom's the national pride as the K-pop expands to the global markets. Secondly, it explores how the Korean fandom rationalizes its possessive instinct while the global fans and markets becomes increasingly important. Finally, it explores how the Korean fandom constructs the different perceptions on foreign fans. In order to observe korean fans' thoughts and activities, it participates in the interactions in the tweeters and an online community. The Korean fans' perspective reflects both on individual tastes and the social dimensions in which fans live through. Through the lens of the Korean fandom, this study attempts to explicate the Korean fans' perception on foreign fans, which reflects another dimension of the K-pop's globalization.

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Development of Micro-Cooling Fans for Cooling of CPU (CPU 냉각용 저소음 Micro-Cooling Fan 의 개발)

  • 김기황;박용민;김진화;이승배
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2001.05a
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    • pp.961-966
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    • 2001
  • Micro fans of randomly swept-blades were designed to provide C.P.U. in a personal computer with effective cooling in a very quiet mode. The proto--type axial micro-fans machined by a laser sintering machine were tested against manufactured products by comparing the performance and overall sound pressure level with spectral measurements in an environment suggested by ASHRAE and ANSI standards. The predicted OSPLs and directivity patterns of fans by iDesignFan software were in good agreements with measured data. The newly introduced fans of randomly swept-blades were proved to provide a very promising mode of low noise at small loading conditions.

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Investigate on the rate of change of CO concentration in a tunnel under changed position of the jet fans by using numerical method (제트 팬 가동위치에 따른 장대터널 내 CO 농도 변화율에 대한 전산해석)

  • Min, Jae-Hong;Kim, Dae-Hyun;Chung, Jin-Taek
    • Proceedings of the KSME Conference
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    • 2008.11b
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    • pp.2765-2770
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    • 2008
  • The purpose of tunnel ventilation system for long road tunnels is to keep certain levels of Visibility Index and the concentration of CO. Additional equipments such as jet fans are used in road tunnel to discharge pollutants in the road tunnel. The control algorism of tunnel ventilation system takes the value of sensors as input, and then gives the operation method of jet fans in tunnel as output. Information on the variation of CO concentration in tunnel when jet fans are running is needed to minimize their operation time. Numerical analysis is used in this paper because of the difficulty of conducting experiments under standard condition for ventilation of road tunnel. The concentration of CO has been calculated by using 3-dimensional CFD under transient condition with speed of cars, quantity of air ventilation, and the results for various operation position of jet fans are compared.

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New Trends in the Production of One Hundred Fans Paintings in the Late Joseon Period: The One Hundred Fans Painting in the Museum am Rothenbaum Kulturen und Künste der Welt in Germany and Its Original Drawings at the National Museum of Korea (조선말기 백선도(百扇圖)의 새로운 제작경향 - 독일 로텐바움세계문화예술박물관 소장 <백선도(百扇圖)>와 국립중앙박물관 소장 <백선도(百扇圖) 초본(草本)>을 중심으로 -)

  • Kwon, Hyeeun
    • MISULJARYO - National Museum of Korea Art Journal
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    • v.96
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    • pp.239-260
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    • 2019
  • This paper examines the circulation and dissemination of painting during and after the nineteenth century through a case study on the One Hundred Fans paintings produced as decorative folding screens at the time. One Hundred Fans paintings refer to depictions of layers of fans in various shapes on which pictures of diverse themes are drawn. Fans and paintings on fans were depicted on paintings before the nineteenth century. However, it was in the nineteenth century that they began to be applied as subject matter for decorative paintings. Reflecting the trend of enjoying extravagant hobbies, fans and paintings on fans were mainly produced as folding screens. The folding screen of One Hundred Fans from the collection of the Museum am Rothenbaum Kulturen und Künste der Welt (hereafter Rothenbaum Museum) in Germany was first introduced to Korean in the exhibition The City in Art, Art in the City held at the National Museum of Korea in 2016. Each panel in this six-panel folding screen features more than five different fans painted with diverse topics. This folding screen is of particular significance since the National Museum of Korea holds the original drawings. In the nineteenth century, calligraphy and painting that had formerly been enjoyed by Joseon royal family members and the nobility in private spaces began to spread among common people and was distributed through markets. In accordance with the trend of adorning households, colorful decorative paintings were preferred, leading to the popularization of the production of One Hundred Fans folding screens with pictures in different shapes and themes. A majority of the Korean collection in the Rothenbaum Museum belonged to Heinrich Constantin Eduard Meyer(1841~1926), a German businessman who served as the Joseon consul general in Germany. From the late 1890s until 1905, Meyer traveled back and forth between Joseon and Germany and collected a wide range of Korean artifacts. After returning to Germany, he sequentially donated his collections, including One Hundred Fans, to the Rothenbaum Museum. Folding screens like One Hundred Fans with their fresh and decorative beauty may have attracted the attention of foreigners living in Joseon. The One Hundred Fans at the Rothenbaum Museum is an intriguing work in that during its treatment, a piece of paper with the inscription of the place name "Donghyeon" was found pasted upside down on the back of the second panel. Donghyeon was situated in between Euljiro 1-ga and Euljiro 2-ga in present-day Seoul. During the Joseon Dynasty, a domestic handicraft industry boomed in the area based on licensed shops and government offices, including the Dohwaseo (Royal Bureau of Painting), Hyeminseo (Royal Bureau of Public Dispensary), and Jangagwon (Royal Bureau of Music). In fact, in the early 1900s, shops selling calligraphy and painting existed in Donghyeon. Thus, it is very likely that the shops where Meyer purchased his collection of calligraphy and painting were located in Donghyeon. The six-panel folding screen One Hundred Fans in the collection of the Rothenbaum Museum is thought to have acquired its present form during a process of restoring Korean artifacts works in the 1980s. The original drawings of One Hundred Fans currently housed in the National Museum of Korea was acquired by the National Folk Museum of Korea between 1945 and 1950. Among the seven drawings of the painting, six indicate the order of their panels in the margins, which relates that the painting was originally an eight-panel folding screen. Each drawing shows more than five different fans. The details of these fans, including small decorations and patterns on the ribs, are realistically depicted. The names of the colors to be applied, including 'red ocher', 'red', 'ink', and 'blue', are written on most of the fans, while some are left empty or 'oil' is indicated on them. Ten fans have sketches of flowers, plants, and insects or historical figures. A comparison between these drawings and the folding screen of One Hundred Fans at the Rothenbaum Museum has revealed that their size and proportion are identical. This shows that the Rothenbaum Museum painting follows the directions set forth in the original drawings. The fans on the folding screen of One Hundred Fans at the Rothenbaum Museum are painted with images on diverse themes, including landscapes, narrative figures, birds and flowers, birds and animals, plants and insects, and fish and crabs. In particular, flowers and butterflies and fish and crabs were popular themes favored by nineteenth century Joseon painters. It is noteworthy that the folding screen One Hundred Fans at the Rothenbaum Museum includes several scenes recalling the typical painting style of Kim Hong-do, unlike other folding screens of One Hundred Fans or Various Paintings and Calligraphy. As a case in point, the theme of "Elegant Gathering in the Western Garden" is depicted in the Rothenbaum folding screen even though it is not commonly included in folding screens of One Hundred Fans or One Hundred Paintings due to spatial limitations. The scene of "Elegant Gathering in the Western Garden" in the Rothenbaum folding screen bears a resemblance to Kim Hong-do's folding screen of Elegant Gathering in the Western Garden at the National Museum of Korea in terms of its composition and style. Moreover, a few scenes on the Rothenbaum folding screen are similar to examples in the Painting Album of Byeongjin Year produced by Kim Hong-do in 1796. The painter who drew the fan paintings on the Rothenbaum folding screen is presumed to have been influenced by Kim Hong-do since the fan paintings of a landscape similar to Sainsam Rock, an Elegant Gathering in the Western Garden, and a Pair of Pheasants are all reminiscent of Kim's style. These paintings in the style of Kim Hong-do are reproduced on the fans left empty in the original drawings. The figure who produced both the original drawings and fan paintings appears to have been a professional painter influenced by Kim Hong-do. He might have appreciated Kim's Painting Album of Byeongjin Year or created duplicates of Painting Album of Byeongjin Year for circulation in the art market. We have so far identified about ten folding screens remaining with the One Hundred Fans. The composition of these folding screens are similar each other except for a slight difference in the number and proportion of the fans or reversed left and right sides of the fans. Such uniform composition can be also found in the paintings of scholar's accoutrements in the nineteenth century. This suggests that the increasing demand for calligraphy and painting in the nineteenth century led to the application of manuals for the mass production of decorative paintings. As the demand for colorful decorative folding screens with intricate designs increased from the nineteenth century, original drawings began to be used as models for producing various paintings. These were fully utilized when making large-scale folding screens with images such as Guo Ziyi's Enjoyment-of-Life Banquet, Banquet of the Queen Mother of the West, One Hundred Children, and the Sun, Cranes and Heavenly Peaches, all of which entailed complicated patterns. In fact, several designs repeatedly emerge in the extant folding screens, suggesting the use of original drawings as models. A tendency toward using original drawings as models for producing folding screens in large quantities in accordance with market demand is reflected in the production of the folding screens of One Hundred Fans filled with fans in different shapes and fan paintings on diverse themes. In the case of the folding screens of One Hundred Paintings, bordering frames are drawn first and then various paintings are executed inside the frames. In folding screens of One Hundred Fans, however, fans in diverse forms were drawn first. Accordingly, it must have been difficult to produce them in bulk. Existing examples are relatively fewer than other folding screens. As discussed above, the folding screen of One Hundred Fans at the Rothenbaum Museum and its original drawings at the National Museum of Korea aptly demonstrate the late Joseon painting trend of embracing and employing new painting styles. Further in-depth research into the Rothenbaum painting is required in that it is a rare example exhibiting the influence of Kim Hong-do compared to other paintings on the theme of One Hundred Fans whose composition and painting style are more similar to those found in the work of Bak Gi-jun.