• Title/Summary/Keyword: Distribution pattern

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Effects of Annular Gap Size on the Flow Pattern and Void Distribution in a Vertical Upward Two-Phase Flow (수직상향 이상류에서 동심원관 간극이 유동양식과 보이드분포에 미치는 영향)

  • Son B. J.;Kim I. S.;Kim M. C.
    • The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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    • v.16 no.4
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    • pp.383-391
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    • 1987
  • An experimental investigation has been conducted to determine the flow pattern for two-component , two-phase mixtures which flow vertically upwards in concentric annuli based on the measurement for the local void fraction and the distribution of the local void fraction in various radial locations in the annular gap. The annular test section consists of a lucite outer tube whose inside diameter is 38mm and a stainless steel rod, The rod diameter is either :2mm,16mm or 20mm. It is demonstrated that the probability density function of the fluctuations in void fraction may be used as an flow pattern indicator and the local void fraction distribution depends on the flow pattern and radial location in the annular passage.

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Spatial Distribution Pattern of Parking Lots in Cheongju City, Korea (청주시 주차장의 공간적 분포 패턴)

  • 손선미;한주성
    • Journal of the Korean Geographical Society
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    • v.37 no.4
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    • pp.337-356
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    • 2002
  • It was proven that the spatial distribution pattern of the parking lots in Cheongju city was clarified through the concentric expansion of the parking lots, which started out from the center for commercial and business function, into the periphery regions. First of ail, in terms of the spatial distribution pattern of the parking lot according to the operational subject, the parking lot is distributed through private, public, and parking lots attached to buildings in the center, and in its adjacent regions, public and parking lots attached to buildings are distributed. And public parking lot, private and parking lots attached to buildings are distributed in sector pattern. And in terms of facility structure, more than half of the parking lots attached to buildings in Cheongju city are composed of Parking lots of self-driver type. In the case of the center, regional structure of self-Parking type of parking lots attacked to buildings, self-parking type lots on plane street parking, mechanical parking types attached to buildings, self-parking type of plane non-street diversely appear to be combined types, its spatial facility distribution patterns appear to be concentric patterns. Also, in terms of the spatial distribution pattern of the parking lots according to the contact types, with the centralizing of a center, southwestern regions show hourly and monthly charged parking lots; northeastern regions show free parking lots. The spatial distribution pattern of the parking lots as above, reflects the regional distribution change of the establishment and residential location.

Relationship between Pattern of Fatigue Crack Surface and Fatigue Crack Growth Behavior under $K_{III}$ Mode-Four Point Shear in Al 5083-O

  • Kim Gun-Ho;Won Young-Jun;Sakakur Keigo;Fujimot Takehiro;Nishioka Toshihisa
    • Journal of Advanced Marine Engineering and Technology
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    • v.30 no.4
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    • pp.474-482
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    • 2006
  • Generally almost all fatigue crack growth is affected by mode I. For this reason a study on mode I has concentrated in the field of fracture mechanics. However the fatigue crack initiation and growth in machines and structures usually occur in mixed mode loading. If there is any relationship between the cause of fracture in mixed mode loading and fracture surface, fracture surface pattern will be the main mean explaining reasons of fatigue fracture and obtaining further information about fracture process. In this paper low point shear-fatigue test with Aluminum alloy hi 5083-O is carried out from this prospect and then the mixed mode distribution of fracture surface is examined from the result after identifying the generation of fatigue crack surface pattern. It was found from the experimental results that the fatigue crack surface pattern and the fatigue crack shear direction are remarkably consistent. Furthermore It is possible that the analysis of distribution of mixed mode through the fatigue crack surface pattern.

Relationship between Pattern of Fatigue Crack Surface and Fatigue Crack Growth Behavior under $K_{III}$ Mode-Four Point Shear in Al 5083-O (Al 5083-O재에 있어서 $K_{III}$ 모드 4점 전단 하에서의 피로파단면 무늬와 피로균열진전거동의 관계)

  • Kim, Gun-Ho;Won, Young-Jun;Sakakura, Keigo;Fujimoto, Takehiro;Nishioka, Toshihisa
    • Proceedings of the Korean Society of Marine Engineers Conference
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    • 2006.06a
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    • pp.43-44
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    • 2006
  • Generally almost all fatigue crack growth is affected by model. For this reason a study on model has concentrated in the field of fracture mechanics. However the fatigue crack initiation and growth in machines and structures usually occur in mixed mode loading. If there is any relationship between the cause of fracture in mixed mode loading and fracture surface, fracture surface pattern will be the main mean explaining reasons of fatigue fracture and obtaining further information about fracture process. In this paper four point shear-fatigue test with Aluminum alloy Al 5083-O is carried out from this prospect and then the mixed mode distribution of fracture surface is examined from the result after identifying the generation of fatigue crack surface pattern. It was found from the experimental results that the fatigue crack surface pattern and the fatigue crack shear direction are remarkably consistent. Furthermore It is possible that the analysis of distribution of mixed mode through the fatigue crack surface pattern.

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A Study on the Distribution of Streamside Vegetation in Kyonganchon (경안천에서 하천변 식생의 분포에 관한 연구)

  • Cho, Do-Soon
    • The Korean Journal of Ecology
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    • v.18 no.1
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    • pp.55-62
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    • 1995
  • This study was conducted to investigate the distribution pattern of plants on streamside of Kyonganchon, which is a tributary of the Han River, and to determine the relationships between plant distribution and environmental factors. Fifteen study sites were selected along the Kyonganchon, and vegetation distribution pattern and soil environmental factors were determined. The most frequently ocurring species in the study sites were Persicaria thunbergii, Persicaria hydropiper, Echinochloa crus-galli and Bidens frondosa, and among them the two Persicaria species were dominants of the community. Many species showed different distribution along the stream:Chenopodium album, Equisetum arvense and Setaria viridies occurred in the upstream region, while Rumex crispus, Leonurus sibiricus and Rorippa islandica occurred in the middle and downstream regions. Analysis of soil properties showed that organic matter and clay content were higher in the upstream region while sand content was higher in the downstream region. The results of DCA ordination showed that axis one was positively correlated with organic matter and clay content and negatively correlated with sand content, indicating that the distribution pattern of vegetation along the Kyonganchon was determined by elevational gradient from upstream to downstream region or gradient of stream width and water level, and by soil organic matter content and soil texture related to these gradients.

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A lateral load pattern based on energy evaluation for eccentrically braced frames

  • Fakhraddini, Ali;Fadaee, Mohammad Javad;Saffari, Hamed
    • Steel and Composite Structures
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    • v.27 no.5
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    • pp.623-632
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    • 2018
  • Performance-Based Plastic Design (PBPD) method has been recently developed to evaluate the behavior of structures in different performance levels. The PBPD method utilizes a base shear force and a lateral load pattern that are estimated based on energy and yielding mechanism concepts. Using of current lateral force pattern results in weak structural members in upper stories of a structure so that the values of the story drift in these stories are larger than the target drift, particularly in high-rise buildings. Therefore, such distribution requires modifications to overcome this drawback. This paper proposes a modified lateral load pattern for steel Eccentrically Braced Frames (EBFs) based on parametric study. In order to achieve the modified load pattern, a group of 26 EBFs has been analyzed under a set of 20 earthquake ground motions. Additionally, results of nonlinear dynamic analyses of EBFs have been post-processed by nonlinear regression analysis in order to derive the new load pattern. To prove the efficiency of present study, three EBFs as examples were designed by modified pattern and current PBPD distribution. Inelastic dynamic analyses results showed that the story drifts using modified lateral load pattern were well within the target values in comparison with current pattern in PBPD, particularly where the effect of the height is significant. The modified load pattern reduces the possibility of underdesigning in upper levels and overdesigning in lower levels of the frames.

Characteristics and Distribution Pattern of Eupatorium rugosum at Mt. Namsan in Seoul (서양등골나물의 생육특성과 남산에서의 분포)

  • 서민환;길지현;김기대;이유미
    • The Korean Journal of Ecology
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    • v.20 no.4
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    • pp.285-291
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    • 1997
  • The taxonomic characteristics of Eupatorium rugosum were reviewed and growth responses under different light intensities were investigated. Changes of soil and vegetation environments at experimental plots on Mt. Namsan were surveyed and the distribution pattern examined. The distribution of E. rugosum was closely related to the content of total nitrogen and available phosphorus in the soil. No competitors which could inhibit the growth of E. rugosum were present. Growth of E. rugosum was highest at a light intensity of 7, 500 lux, but dry weight was highest at a light intensity of 15, 000 lux followed by 30, 000 and 7, 500 lux. Growth in height of E. rugosum under a light intensity of 1, 500 lux continued even though the amount of growth was small. E. rugosum is found throughout the area of Mt. Namsan, and its density is higher at the roadside and in valley regions. E. rugosum appeared at 25 of 50 quadrats on Mt. Namsan, and the mean coverage of E. rugosum in survey quadrats was 12%.

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Analysis on LGP with Multi-Side-Lamp (다변 광원 도광판에 대한 연구)

  • Park Jong-Ryul;Sah Jong-Youb
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.29 no.3 s.234
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    • pp.361-368
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    • 2005
  • LGP(Light-Guide Panel) of LCD backlight is one of the major componets which affect on the product quality of LCD. The LGP with multi-side lamp has been analized for pattern design with the uniform distribution of brightness. When given the uniform distribution of brightness as target, the distribution of dot pattern has been designed for superposed distributions of brightness for each lamp. Multi-side lamp has been tested for various types such as ㄴ-, ㄷ-, and ㅁ -shapes. The present study enhances the possibility of LGP with multi-side lamp by showing the pricise control of brightness distribution.

Vertical Distribution of Phytoplankton in the Paldang Dam Reservior (팔당댐 담수수역 식물플랑크톤의 수직분포)

  • Lee, Kyung
    • Journal of Plant Biology
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    • v.29 no.2
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    • pp.117-127
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    • 1986
  • Phytoplankton community was investigated at the Paldang Dam Reservoir in the Mid-Han River by it's depth, in spring and summer known as the period of phytoplankton's blooming. It was only in summer that phytoplankton bloomed at the investigated area. 128 kinds of phytoplankton were identified and of them, diatoms were abundunt in spring but cyanophyta and chlorophyta were in summer. Because some species with high pollution index were observed in summer, it could be proved that the investigated area was polluted especially in summer. In spring shown the circulation period by vertical distribution pattern of chlorophyll-a and isothermal distribution pattern of water temperature, maximum value of phytoplankton standing crops appeared at the upper layer, except for surface layer. In summer shown the circulation period after the stagnation period by vertical distribution pattern of chlorophyll-a and immediate destruction after stratification of water temperature, maximum value of phytoplankton standing crops appeared at the lower layer. the layer at which the maximum value of chlorophyll-a appeared also accorded with that of phytoplankton standing crops. So, it could be approved that there existed a close relationship among phytoplankton standing crops, chlorophyll-a, and water temperature.

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A Study for Distribution of Pattern Identification by Age in Stroke Patients (중풍 환자의 연령에 따른 변증 유형 분포에 대한 연구)

  • Yeo, Hyeon-Su;Hsia, Yu-Chun;Baik, Jong-Woo;Park, Jong-Hyung;Choi, You-Kyung;Ko, Ho-Yeon;Cho, Ki-Ho;Jang, Bo-Hyung;Ko, Seung-Gyu;Han, Chang-Ho;Bang, Ok-Sun;Jun, Chan-Yong
    • The Journal of Korean Medicine
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    • v.30 no.2
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    • pp.145-151
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    • 2009
  • Objectives: The purpose of this study was to investigate distribution of pattern identification by age in stroke patients. Methods: From 1 April, 2007 to 29 September, 2008, 903 patients within a month after onset of stroke were included. Stroke patients were interviewed by oriental medicine doctors who used standard operation procedures for this study. A questionnaire was completed by a question-and-answer form between patients and doctors after explanation of details to patients and patients' agreement given. Results: Distributions of pattern identification in stroke patients differed by age groups. Dampness-Phlegm pattern was more common in the younger group aged under 80 years, while Yin-Deficiency pattern was more common in the older group aged over 80 years. Conclusions: In this study, we found a character of distribution of pattern identification by age in stroke patients within one month after stroke onset. We have concluded that these differences should be considered in the management and treatment of stroke patients.

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