• Title/Summary/Keyword: disperse model

검색결과 58건 처리시간 0.023초

Application of Modified Stokes Expression to Model the Behavior of Expanded Beds with Feed Streams Containing E. coli Homogenates

  • Chae, Young-Rea;Yoon, Yeo-Joon;Ryu, Keun-Garp
    • Biotechnology and Bioprocess Engineering:BBE
    • /
    • 제9권4호
    • /
    • pp.323-325
    • /
    • 2004
  • To model the behavior of expanded beds with aqueous feed streams containing different amounts of glycerol, we previously developed a modified Stokes expression that correlates the terminal settling velocity of a particle of a solution with the properties of the particle (particle diameter and density) and the solution (density and viscosity). Two empirical parameters, the effective diameter of the poly-disperse resins for protein adsorption and an exponent of non-unity for $(\rho_{P}-\rho)/\mu$ term, are introduced in the modified Stokes expression. We applied the same type of the modified Stokes expression in combination with the Richardson-Zaki correlation to the published results [1], and found that the expansions of the beds with feed streams containing different amounts of E. coli homogenates can also be successfully described.

봄철 서해안 해무의 수치예보 (Numerical forecasting of sea fog at West sea in spring)

  • 한경근;김영철
    • 한국항공운항학회지
    • /
    • 제14권4호
    • /
    • pp.94-100
    • /
    • 2006
  • The purpose of this case study is to determine the possibility of Numerical Forecasting of sea fog at West Sea in spring time. For practical method of analyzing the data collected from 24th to 26th March 2003, Numerical Weather Prediction model MM5(Mesoscale Model Version 5) and synoptic field study using synoptic chart, upper level chart, and sea surface temperature were employed. The results of synoptic field analysis summarized that sea fog at West sea in spring is intensified by the inflow of the warm flow from west or southwest, low sea surface temperature to increase the temperature difference between air and sea surface, and inversion layer to disturb the disperse. It appears that the possibility of sea fog forecasting by MM5, in view of the result that the MM5 output is similar to the synoptic fields analysis.

  • PDF

인공신경망을 이용한 평면파괴 안정성 예측 (A Prediction of the Plane Failure Stability Using Artificial Neural Networks)

  • 김방식;이성기;서재영;김광명
    • 한국지반공학회:학술대회논문집
    • /
    • 한국지반공학회 2002년도 가을 학술발표회 논문집
    • /
    • pp.513-520
    • /
    • 2002
  • The stability analysis of rock slope can be predicted using a suitable field data but it cannot be predicted unless suitable field data was taken. In this study, artificial neural networks theory is applied to predict plane failure that has a few data. It is well known that human brain has the advantage of handling disperse and parallel distributed data efficiently. On the basis of this fact, artificial neural networks theory was developed and has been applied to various fields of science successfully In this study, error back-propagation algorithm that is one of the teaching techniques of artificial neural networks is applied to predict plane failure. In order to verify the applicability of this model, a total of 30 field data results are used. These data are used for training the artificial neural network model and compared between the predicted and the measured. The simulation results show the potentiality of utilizing the neural networks for effective safety factor prediction of plane failure. In conclusion, the well-trained artificial neural network model could be applied to predict the plane failure stability of rock slope.

  • PDF

A study on anti-thrombotic activity of Hwao-tang

  • Park Tae Woo;Park Won Hwan
    • 동의생리병리학회지
    • /
    • 제16권1호
    • /
    • pp.181-185
    • /
    • 2002
  • The thrombosis is the category of blood stasis. Blood stasis is a pathologicial state resulting from the reverse or impeded flow of blood in the body or the stagnation of blood flow in local parts as well as abnormal blood outside of the vessles which remains in the body and fails to disperse. Hwao-tang has been reported to have a hypolipidemic effect in patients with hypercholesterolemia, and in highcholesterol-induced experimental models. The present paper reports the effects of HOT on atherosclerosis using a spontaneous experimental model, Kurosawa and Kusanagi-hypercholesterolemic (KHC) rabbits. We have also investigated the pharmacological effect of extracts obtained from HOT on collagen-and ADP-induced blood platelet aggregation, thrombin-induced conversion of fibrinogen and fibrinolysis in in vitro experiments. In conclusion, the protection of extracts of Korean herbs' HOT on the ischemic infarction induced artificially might be involved to their inhibition of thrombotic action.

복잡한 지형내 오염물질의 대기확산 풍동실험: I. 산지지형에서의 확산 (Wind Tunnel Experiments for Studying Atmospheric Dispersion in the Complex Terrain I.Dispersion in a mountainous Area)

  • 경남호;김영성;손재익
    • 한국대기환경학회지
    • /
    • 제8권3호
    • /
    • pp.169-178
    • /
    • 1992
  • Dispersion of pollutant in a mountainous area is simulated in a wind tunnel. In the northwest side of the terrain model, the sea level is assumed. Wind from the sea initially confronts hills along the shoreline, a line of large buildings next, and finally a valley between high mountains in the south and in the east. In the northwest wind conditions, severe flow separation occurs in the lee side of hills, even beyond the building area. Pollutant from the buildings is trapped in this region and its concentration is the highest. In the west wind conditions, pollutant from the buildings flows along the hills aslant the main wind direction in this case. Since large valley is located in the downstream, pollutant tends to disperse along the valley.

  • PDF

The Facial Expression Recognition using the Inclined Face Geometrical information

  • Zhao, Dadong;Deng, Lunman;Song, Jeong-Young
    • 한국정보통신학회:학술대회논문집
    • /
    • 한국정보통신학회 2012년도 추계학술대회
    • /
    • pp.881-886
    • /
    • 2012
  • The paper is facial expression recognition based on the inclined face geometrical information. In facial expression recognition, mouth has a key role in expressing emotions, in this paper the features is mainly based on the shapes of mouth, followed by eyes and eyebrows. This paper makes its efforts to disperse every feature values via the weighting function and proposes method of expression classification with excellent classification effects; the final recognition model has been constructed.

  • PDF

아민화 폴리아크로니트릴 유도체 현탁액의 전기유변학적 특성 (Electrorheological Properties of Aminated Polyacrylonitrile Susupension)

  • 최웅수;김충현
    • Tribology and Lubricants
    • /
    • 제25권3호
    • /
    • pp.176-181
    • /
    • 2009
  • Aminated polyacrylonitrile as the new organic disperse phases of the anhydrous ER fluid has been synthesized and ER effect of the suspension composed of aminated polyacrylonitrile in silicone oil investigated. The suspension showed a typical ER response (Bingham flow behavior) upon application of an electric field. The shear stress for the suspension exhibited the dependence with a factor equals to 1.6 power on theelectric field. The current density and the conductivity of the of aminated polyacrylonitrile suspension increase with the electric field intensity and moreover the conductivity of the suspension is about 8 order of magnitude higher than that of the silicone oil. On the basis of the the results, aminated polyacrylonitrile suspension showed the ER flow behavior upon application of the electric field due to the polarizability of the branched amine polar group of the aminated polyacrylonitrile particles.

Fundamental study on cancer therapy by blocking newborn blood vessels by magnetic force control

  • KIRIMURA, Makoto;AKIYAMA, Yoko;NISHIJIMA, Shigehiro
    • 한국초전도ㆍ저온공학회논문지
    • /
    • 제20권2호
    • /
    • pp.11-15
    • /
    • 2018
  • In this study, a cancer treatment by accumulating and aggregating ferromagnetic particles in newborn blood vessels was examined. It is necessary for this treatment to control dispersion-aggregation property of ferromagnetic particles. Ferromagnetic particles required in this method disperse at low magnetic field, aggregate at high magnetic field and maintain the aggregation even after removal of the magnetic field. In order to control the dispersion-aggregation property, the surface of magnetite particles was modified with higher fatty acids having different lengths. As a result, we succeeded to prepare propionic acid-modified magnetite particles that form irreversible aggregation by magnetic field. The model experiments simulating newborn blood vessels showed that these particles can block the flow by the magnetic field, and the blockage was maintained after removal of the magnetic field.

A Study on Dispersion Behaviors of Fume Particles in Laser Cutting Process of Optical Plastic Thin Films

  • Kim, Kyoungjin
    • 반도체디스플레이기술학회지
    • /
    • 제18권4호
    • /
    • pp.62-68
    • /
    • 2019
  • The optoelectronic display units such as TFT-LCD or OLED require many thin optical plastic films and their mass manufacturing processes employ CO2 laser cutting of those thin films in a large quantity. However, laser film cutting could generate fume particles through melt shearing, vaporization, and chemical degradation and those particles could be of great concern for film surface contamination. In order to appreciate the fume particle dispersion behaviors in laser film cutting, this study relies on random particle simulations by probabilistic distributions of particle size, ejection velocity and angles coupled with Basset-Boussinesq-Oseen model of particle trajectory in low Reynolds number flows. Here, up to one million particles of random sampling have been tested to effectively show fume particles dispersed on the film surface. The computational results could show that particular range of fume particle size could easily disperse into the pixel region of processed optical films.

Boundary-Fitted 좌표계로 변환한 2차원조석모형의 매개변수 동정 (The Parameter Identification of Tidal Model on The Boundary-Fitted Coordinates)

  • 김경수;이재형
    • 물과 미래
    • /
    • 제23권3호
    • /
    • pp.319-328
    • /
    • 1990
  • 2차원 하구모델의 매개변수 동정을 BF좌표계로 변환된 ADI-FDM출력 수치모형을 사용하여 수행하였다. 모형에서 기본 방정식을 동수역학식과 수송방정식이 복합된 방정식을 사용하였다. Thompson식이 지배방정식을 사각평면으로 변환 하는데 사용도이ㅓㅆ으며 Thompson의 Elliptic 격자발생기법이 BF 좌표계에서 곡선격자망을 발생하는데 사용되었다. 지배방정식에서 동정될 매개변수는 마찰계수와 분산 정수이다. 출력수치모형은 BF좌표계에서 조석평균 염도 모형이 사용되었다. 최적화 기법으로 영향계수 알고리즘을 적용하였다. 또한 Lumped 모형이 동정에 고려 되었다. 본 연구는 새로운 출력 수치모형이 하구염도 모형의 매개변수 동정에 있어 유용한가를 검토 하는데 중점을 두었다. 제안된 기법은 간단한 가상모형에 실험적인 적용을 통하여 검토되었다. 검토한 결과는 제안된 기법이 하구모형에서 매개변수 동정시 도입될 수 있음을 보여주었다.

  • PDF