• Title/Summary/Keyword: Well-mixed condition

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COUPLED COMMON FIXED POINT THEOREMS FOR A CONTRACTIVE CONDITION OF RATIONAL TYPE IN ORDERED METRIC SPACES

  • Chandok, Sumit
    • Journal of applied mathematics & informatics
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    • v.31 no.5_6
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    • pp.643-649
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    • 2013
  • The purpose of this paper is to establish some coupled coincidence point theorems for a pair of mappings having a strict mixed g-monotone property satisfying a contractive condition of rational type in the framework of partially ordered metric spaces. Also, we present a result on the existence and uniqueness of coupled common fixed points. The results presented in the paper generalize and extend several well-known results in the literature.

A Study on Complex Program of the Mixed-Use building - Focusing on Intermediary Space between Public and Private - (주상복합 실내공간의 복합 프로그램에 관한 연구 - 공(公), 사(私) 경계영역을 중심으로 -)

  • Yoon, Se-Eun;Kim, Jong-Jin
    • Proceedings of the Korean Institute of Interior Design Conference
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    • 2006.11a
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    • pp.58-61
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    • 2006
  • The mixed-use building is certainly one of the significant alternatives for urban dwelling based on the over-crowded urban condition as well as the ever-changing contemporary life patterns. It is clear that residential and other programs somehow are becoming more separated in most high quality mixed-use buildings in Seoul. Thus making the space between residential and other programs where diverse multi activities can be inserted is extremely important in terms of bridging the different urban programs. This research aims to briefly analyze the mixed-use programs in contemporary cities and case projects to see how they respond to unique characteristics of each projects by creating different mixed zones and spaces.

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Coprime factor reduction of plant in $H{\infty}$ mixed sensitivity problem

  • Um, Tae-Ho;Oh, Do-Chang;Park, Hong-Bea;Kim, Soo-Joong
    • 제어로봇시스템학회:학술대회논문집
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    • 1995.10a
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    • pp.340-343
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    • 1995
  • In this paper, we get a reduced order controller in $H^{\infty}$ mixed sensitivity problem with weighting functions. For this purpose, we define frequency weighted coprime factor of plant in $H^{\infty}$ mixed sensitivity problem and reduce the coprime factor using the frequency weighted balanced truncation technique. The we design the controller for plant with reduced order coprime factor using J-lossless coprime factorization technique. Using this approach, we can derive the robust stability condition and achieve good performance preservation in the closed loop system with reduced order controller. And it behaves well in both stable plant and unstable plant.t.

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The quality condition of concrete in the hydraulic structures and a plan improving Quality (콘크리트 수리구조물의 품질상태와 개선방향)

  • Park, Kwang-Su;Shin, Su-Kyun;Kim, Kwan-Ho;Lee, Joon-Gu;Kim, Meyong-Won;Jang, Dan-Gum
    • Proceedings of the Korean Society of Agricultural Engineers Conference
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    • 2003.10a
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    • pp.407-410
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    • 2003
  • The actual quality of the concrete in the structure for Irrigation may differ from that represented by the cylinders because the age, consolidation, or curing of the in-place material may not be well represented by the standard test specimens. The objective of this paper is to offer a base data of specification is the best fit the ready-mixed concrete strength to the specified, and to address this deficiency, so that the strength information of the concrete in the structure for Irrigation can be rationally accounted for in the assessment of the quality condition of this. The strength of concrete in the hydraulic structures is checked using strength of core obtained from that, and 28-day-old cylinder strength is analyzed using cylinder data of the ready-mixed concrete.

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Numerical Study on the Ventilation Effect in the Boiler Building (보일러빌딩 내부 환기현상에 관한 수치적 연구)

  • Kim, Chul Hwan;Yoo, Geun Jong;Choi, Hoon Ki
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.15 no.3
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    • pp.239-249
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    • 2005
  • Ventilation effect is analyzed for boiler building with multiple heat sources. Air flow inside the boiler building is characterized as turbulent mixed convection. Analysis methodology is set up with two different $k-{\varepsilon}$ type models (standard $k-{\varepsilon}$, RNG $k-{\varepsilon}$). Two different cases with high and low outside temperature are analyzed. In case of high outside temperature condition, mixed convection is well realized inside the boiler building. With different upper louver opening rate, air flow is also well established and proper opening rate is found to meet design limit in case of low outside temperature condition. Difference of analysis results for two different turbulence models are not significant. Therefore, analysis methodology with simple $k-{\varepsilon}$ turbulence model is found to be reliable for the boiler building ventilation analysis. However, more simplified geometrical model is desired to expand its application.

Particle Dispersion and Effect of Spin in the Turbulent Boundary Layer Flow (난류 경계층 유동에서 입자의 확산과 스핀의 영향)

  • Kim, Byung-Gu;Lee, Chang-Hoon
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.28 no.1
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    • pp.89-98
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    • 2004
  • In this paper, we develope a dispersion model based on the Generalized Langevin Model. Thomson's well-mixed condition is the well known criterion to determine particle dispersion. But, it has 'non-uniqueness problem'. To resolve this, we adopt a turbulent model which is a new approach in this field of study. Our model was greatly simplified under the self-similarity condition, leaving model only two model constants $C_{0}$ and ${\gamma}$$_{5}$ that control the dispersion and spin which measures rotational property of the Lagrangian particle trajectory. We investigated the sign of spin as well as magnitude by using the Direct Numerical Simulation. Model calculations were performed on the neutrally stable boundary layer flow. We found that spin has weak effect on the particle dispersion but it shows the significant effect on the horizontal flux compared to the zero-spin model.

Effect of mixed sowing treatment of green manure crops on the change of soil nitrogen amount and yield production of corn

  • Shim, Kang Bo;Kim, Min Tae;Kim, Sung Gook;Jung, Kun Ho;Kim, Chung Guk;Lee, Jae Un;Kwon, Young Up
    • Proceedings of the Korean Society of Crop Science Conference
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    • 2017.06a
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    • pp.318-318
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    • 2017
  • This study was conducted to find optimum mixed sowing ratio of green manure crops to reduce the use of chemical fertilizer as well as to increase the crop yield potential which will foster the utilization of green manure crops in the upland field in view of environment friendly agriculture. According to the study, the mixed ratio, 50:50, of hairy vetch and green barley showed highest nitrogen production yield in the soil due to the relatively higher organic nitrogen supply from the hairy vetch plant as well as nitrogen fixation from the air rather than other mixed ratio. In the 50:50 mixed ratio of hairy vetch and green barely total nitrogen amount in the soil showed 17.2kg per 10a, but in the other treatment ratio such as 75:25, 25:75. total nitrogen fixation amount were 16.7, 16.9 respectively. We also conducted the experiment to compare the effect of the mixed sowing treatment of green manure crops on the production of corn cultivated as a succeeding plant of hairy vetch. According to the result, the mixed ratio, 50:50, of hairy vetch and green barley treatment showed highest yield potential of corn as 153kg per 10a in seed weight which is due to the relatively higher organic nitrogen supply from the hairy vetch plant as well as nitrogen fixation from the air rather than other mixed ratio. In the mixed sowing treatment of hairy vetch 100 and barley 0 ratio, the corn production showed 148kg per 10a which is 5kg lower than that of hairy vetch 50 and barley 50 ratio, but showed statistically no difference between those two treatment. Otherwise, different treatments, such as hairy vetch 75 and barley 25, 25 and 75, 0 and 100 showed statistically different each other. Therefore, it was concluded that green manure crops, such as hairy vetch, green barley and rye were very effective crops to increase the soil fertility and gave the positive effect to the crops to give vegetative and propagative growth condition and, in turn, increased the yield potential. We have to make policy to enhance the utility of green manure crops in the upland crops as well as faddy field for the soil fertility and crop yield production which will guarantee prominent quality of environment friendly agriculture products.

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Evaluation of One-particle Stochastic Lagrangian Models in Horizontally - homogeneous Neutrally - stratified Atmospheric Surface Layer (이상적인 중립 대기경계층에서 라그랑지안 단일입자 모델의 평가)

  • 김석철
    • Journal of Korean Society for Atmospheric Environment
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    • v.19 no.4
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    • pp.397-414
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    • 2003
  • The performance of one-particle stochastic Lagrangian models for passive tracer dispersion are evaluated against measurements in horizontally-homogeneous neutrally-stratified atmospheric surface layer. State-of-the-technology models as well as classical Langevin models, all in class of well mixed models are numerically implemented for inter-model comparison study. Model results (far-downstream asymptotic behavior and vertical profiles of the time averaged concentrations, concentration fluxes, and concentration fluctuations) are compared with the reported measurements. The results are: 1) the far-downstream asymptotic trends of all models except Reynolds model agree well with Garger and Zhukov's measurements. 2) profiles of the average concentrations and vertical concentration fluxes by all models except Reynolds model show good agreement with Raupach and Legg's experimental data. Reynolds model produces horizontal concentration flux profiles most close to measurements, yet all other models fail severely. 3) With temporally correlated emissions, one-particle models seems to simulate fairly the concentration fluctuations induced by plume meandering, when the statistical random noises are removed from the calculated concentration fluctuations. Analytical expression for the statistical random noise of one-particle model is presented. This study finds no indication that recent models of most delicate theoretical background are superior to the simple Langevin model in accuracy and numerical performance at well.

A Study on the Planning Tendency of the Mixed-Use School Facilities (학교시설(學敎施設)의 복합화(複合化) 성향(性向)에 관한 연구(硏究))

  • Kang, Jin-A;Oh, Deog-Seong
    • Journal of the Korean Institute of Educational Facilities
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    • v.7 no.4
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    • pp.5-15
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    • 2000
  • As the core of community, schools should play not only for the educational facilities but also for the public facilities. With the mixture of those facilities, the people in the community are able to use these facilities conveniently. The students could also make the best use of the school with the well-established facilities for sport and cultural functions. With those consideration in mind, this study aims to identify the planning feature of mixed-use school. Firstly, the concept of mixed-use and the typology of the development are reviewed. The pre-condition for the design of the mixed-use school are also studied with consideration of the planning tendencies of mixed-use schools in four countries(UK, USA, Japan and Korea). Secondly, eight case schools are selected in Japan and Korea. We analyzed them in terms of following three aspects; 1) The major functions to combine with school design, 2) The spatial arrangement how different functions could be connected in horizontal and vertical order, 3) The circulation system with which students and different user are able to access separately to those function.

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Coprime factor reduction of plant in $H{\infty}$ mixed sensitivity problem ($H{\infty}$ 혼합감도문제에서 플랜트의 소인수요소줄임)

  • 음태호;오도창;박홍배;김수중
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.33B no.2
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    • pp.20-27
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    • 1996
  • In this paper, we propose a coprime factor model reduction method to get a reduced order controller in $H^{\infty}$ mixed sensitivity problem with frequency weighting functions. for this purpose, the given $H^{\infty}$ mixed sensitivity problem is transformed into robust stabilization problem with coprime factor uncertainty of given plant. This method is to define frequency weighted coprime factors of plant in CSD (chain scattering description) form and reduce the coprime factors using weighted balanced truncation. then a controller is designed to the reduced order coprime factors using J-lossless coprime factorization method. Using this approach, the robust stability condition is derived and good performance is preserved in closed loop system with the given plant and the reduced order controller. Also the order of reduced controller for guaranteeing the robust stability can be determined before designing the reduced controller. The proposed method behaves well in both stable and unstable plant.

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