• Title/Summary/Keyword: formation dynamics

Search Result 465, Processing Time 0.028 seconds

Evolution of suspended sediment patterns in the East China and Yellow Seas

  • Ahn, Yu-Hwan;Shanmugam, Palanisamy;Gallegosi, Sonia
    • Journal of the korean society of oceanography
    • /
    • v.39 no.1
    • /
    • pp.26-34
    • /
    • 2004
  • The evolution of intricate and striking patterns of suspended sediments (SS), which are created by certain physical dynamics in the East China and Yellow Seas, has been investigated using satellite ocean color imageries and vertical profiles of particle attenuation and backscattering coefficients. The structure of these patterns can reveal a great deal about the process underlying their formation. Sea surface temperature (SST) analyzed from the Advanced Very High Resolution Radiometer (AVHRR) thermal infrared data were used to elucidate the physical factors responsible for the evolution of suspended sediment patterns in the East China Sea. The concomitant patterns of suspended sediments were tracked from the Sea-viewing Wide Field-of-view Sensor (SeaWiFS) ocean color data. The detailed examination about these patterns gave birth to the definition of the evolution of suspended sediments (SS) into four stages: (1) Youth or Infant stage, (2) Younger stage, (3) Mature stage, and (4) Old stage. We describe about the three directional forces of the tidal currents, ocean warm currents and estuarine circulations that lead to occurrence of various stages of the evolution of suspended sediments that increase turbidity at high levels through out the water column of the inner and outer shelf areas during September to April. The occurrence of these four stages could be repeatedly observed. In contrast, vertical profiles of the particle attenuation ($c_{p}$) and backscattering ($b_{bp}$) coefficients displayed obvious patterns of the propagation of suspended sediment plume from the southwestern coastal sea that leads to eventual collision with the massive sediment plume originating from the Yangtze banks of the East China Sea.

Analysis of the Adsorbed Plasma Proteins in the Moving Actuator type Total Artificial Heart

  • Gyu Ha Ryu;Jon
    • Journal of Biomedical Engineering Research
    • /
    • v.14 no.4
    • /
    • pp.307-314
    • /
    • 1993
  • Plasma protein adsorption is the first event in the blood-material interaction and influenc- es subsequent platelet adhesion towards thlㅈombus formation. Thiㅈomboembolic events are strongly influenced by surface characteristics of materials and fluid dynamics inside the blood pump. In vitro flow visualizaion and an amimal experiment with the moving actuator type TAH were Performed in order to investigate fluid dynamic effects on the protein adsorption. The diffel'encl level, j of shear rate inside the ventricle Lvere determined by consid- ering the direction of the major opening of four healt valves in the implanted TAH and the visualized flow patterns as well. Each ventricle of the explanted TAH was sectionalized into 12 segments according to the shear rate level. The adsorbed protein on each segment was quantified using the ELISA method after soaking in 2% (wye)SDS/PBS for two days. Adsorbed protein layer thicknesses Itvere measured by the Immunogotd method under TEM. The SEM observation show that right ventricle (RV) , immobilized with albumin, displayed different degrees of platelet adhesion on each segment, whereas the left ventricle (LV), grafted by PEO-sulronate, indicated nearly , iame platelet adhesion behavior, regardless of shear rates. The surface concentrations of adsorbed proteins in the low shear rate region are hlghel'than those in the high region, which was confirmed statistically. A modified adsorption model of plasma protein onto polyurethane surface was suggested by considering the effect of the fluid dynamic characteristics.

  • PDF

A Study on the Equilibrium Theory of Business Administration Organization (경영조직의 균형이론에 관한 연구 -"바아나이드" 및 "마취-사이몬"의 이론을 중심으로-)

  • 이경희
    • The Journal of Fisheries Business Administration
    • /
    • v.9 no.1
    • /
    • pp.29-46
    • /
    • 1978
  • The Equilibrium Theory is one of the key theories on the study of maintenance and continuance of organization. A contributor or participant of the business organization has been given the needed incucements and motivated to join in business. To keep this situation balanced is, so-called, the organization equilibrium. C. I. Barnard was the first to research this, and that J. G. March and H. A. Simon advanced it. Modern organization theory is not only the equilibrium theory but continuance theory of organization. That is, the continuance of business administration organization relies on the willingness to cooperate with which the participants in business try to devote themselves to business. The organization itself is not only combined with its members and assets but a kind of behaviour system which every member makes an effort to contribute. On a view of dynamics, organization remains, prospers and deceases in process of its formation, disorganization and reformation. But taking consideration into going concern, it is necessary that we should plan to strike a balance of business administration organization. We can write down the proposition of this theory as follows: The continuance and growth of organization=inducements contribution The basic idea of this theory was established by C. I. Barnard. But it implied many problems such as incorrect statistical measures and the defects of objectivity. These problems were more or less rearranged and improved by so-called March-Simon's equilibrium theory. Especially March-Simon's general models of organization equilibrium are a great success in this field. In the future, these problems mentioned above will be a challenge to workers in this field how we shall diminish the defects to the minimum and how perfectly we can progress it.

  • PDF

Community Should Be Invented Focusing on Maeul Media in Seoul (공동체는 발명되어야 한다 서울시 마을미디어 형성과 활동을 중심으로)

  • Kim, Yeran;Kim, Yong Chan;Chae, Young Gil;Baek, Young Min;Kim, Eujong
    • Korean journal of communication and information
    • /
    • v.81
    • /
    • pp.40-74
    • /
    • 2017
  • Drawn upon the analysis of Seoul community media, this study make six points. The generation of community is not essentially determined but has singularity and differences. Historical context, social conditionality, cultural orientation, and the subjects' will and anticipation bring out certain forms of community. Various power relations and desires are engaged in the formation of community. The process of the construction of community is necessarily and simultaneously mediated with collective acts of communication and sharing. Community is not so much cultivated within society as articulated with precariousness, negativity and limit. Community is able to create its own cultural sensibility and language to express it. Thereby community is a dynamics between articulation and disarticulation, convergency and divergency, similitude and difference living in our actual society.

  • PDF

TWO MOLECULAR CLOUDS WITH ANOMALOUS VELOCITIES IN THE GALACTIC ANTICENTER

  • Lee, Youngung;Kim, Young Sik;Kim, Hyung-Goo;Jung, Jae-Hoon;Yim, In-Sung;Kang, Hyunwoo;Lee, Changhoon;Kim, Bong-Gyu;Kim, Kwang-Tae
    • Journal of The Korean Astronomical Society
    • /
    • v.47 no.6
    • /
    • pp.319-325
    • /
    • 2014
  • We map two molecular clouds located in the exact anticenter region emitting in the (J = 1-0) transition of $^{12}CO$ and $^{13}CO$ using the 3-mm SIS mixer receiver on the 14-m radio telescope at Taeduk Radio Astronomy Observatory. The target clouds with anomalous velocities of $V_{LSR}{\sim}-20km\;s^{-1}$ are distinguished from other clouds in this direction. In addition, they are located in the interarm region between the Orion Arm and the Perseus Arm. Sizes of the clouds are estimated to be about 8.6 and 10.8 pc, respectively. The total mass is estimated to be about $4{\times}10^3$ $M_{\odot}$ using CO luminosity of the clouds. Several cores are detected, but no sign of star formation is found according to the IRAS point sources. Their larger linewidths, anomalous velocities, and their location at the interarm region make these clouds more distinguished, though their physical properties are similar to the dark clouds in the solar neighborhood in terms of mass and size.

Seed-born Burkholderia glumae Infects Rice Seedling and Maintains Bacterial Population during Vegetative and Reproductive Growth Stage

  • Pedraza, Luz Adriana;Bautista, Jessica;Uribe-Velez, Daniel
    • The Plant Pathology Journal
    • /
    • v.34 no.5
    • /
    • pp.393-402
    • /
    • 2018
  • Rice world production is affected due to the growing impact of diseases such as bacterial panicle blight, produced by Burkholderia glumae. The pathogen-induced symptoms include seedling rot, grain rot and leafsheath browning in rice plants. It is currently recognized the entrance of this pathogen to the plant, from infected seeds and from environmental sources of the microorganism. However, it is still not fully elucidated the dynamics and permanence of the pathogen in the plant, from its entry until the development of disease symptoms in seedlings or panicles. In this work it was evaluated the infection of B. glumae rice plants, starting from inoculated seeds and substrates, and its subsequent monitoring after infection. Various organs of the plant during the vegetative stage and until the beginning of the reproductive stage, were evaluated. In both inoculation models, the bacteria was maintained in the plant as an endophyte between $1{\times}10^1$ and $1{\times}10^5cfu$ of B. $glumae.g^{-1}$ of plant throughout the vegetative stage. An increase of bacterial population towards initiation of the panicle was observed, and in the maturity of the grain, an endophyte population was identified in the flag leaf at $1{\times}10^6cfu$ of B. $glumae.g^{-1}$ fresh weight of rice plant, conducting towards the symptoms of bacterial panicle blight. The results found, suggest that B. glumae in rice plants developed from infected seeds or from the substrate, can colonize seedlings, establishing and maintaining a bacterial population over time, using rice plants as habitat to survive endophyticly until formation of bacterial panicle blight symptoms.

Numerical Analysis of a Liquid Sheet Flow around a Simplified Sprinkler Head Using a CFD Model (CFD 모델을 이용한 단순 스프링클러 헤드 주위의 액막 유동해석)

  • Kim, Sung-Chan
    • Fire Science and Engineering
    • /
    • v.30 no.6
    • /
    • pp.111-117
    • /
    • 2016
  • The present study examined the free surface flow of a liquid sheet near a sprinkler head using a Computational Fluid Dynamics (CFD) model and considered the feasibility of the empirical model for predicting the initial spray characteristics of the sprinkler head through a comparison of the CFD results. The CFD calculation for a simplified sprinkler geometry considering the nozzle and deflector were performed using the commercially available CFD package, CFX 14.0 with the standard $k-{\varepsilon}$ turbulence model and theVolume of Fluid (VOF) method. The predicted velocity of the empirical model at the edge of deflector were in good agreement with that of the CFD model for the flat plate region but there was a certain discrepancy between the two models for the complex geometry region. The mean droplet diameter predicted by the empirical model differed significantly from the measured value of the real sprinkler head. On the other hand, the empirical model can be used to understand the mechanism of droplet formation near the sprinkler head and predict the initial spray characteristics for cases without experimental data.

Proper motion of Galactic globular cluster NGC 104

  • Kim, Eun-Hyeuk;Kim, Min-Sun
    • The Bulletin of The Korean Astronomical Society
    • /
    • v.35 no.2
    • /
    • pp.84.1-84.1
    • /
    • 2010
  • Globular clusters (GCs) are known to be one of the oldest objects in the Milky Way. Therefore the dynamical informations of GCs are very important to understand the formation and evolution of our Galaxy. Motion of GCs in the halo of Galaxy can be traced by radial velocities of individual stars and proper motions of GCs. Measuring the radial velocities of stars in GCs has been challenging for decades because the brightness of stars (even for the brightest stars) in GCs are too faint (V>14) to measure the radial velocities. The available large telescopes (D>4m) enable us to observe the spectra of stars in the red giant branch of GCs, and it is now more plausible to measure the radial velocities of stars in GCs. On the contrary it is still very difficult to measure the sky-projected two-dimensional motion of GCs in Galaxy even with the large telescopes because the distance to GCs is quite large (~10kpc) compared to the spatial resolution of present-day large ground-based telescopes. Instruments on-board Hubble Space Telescope are ideal to study the proper motion of GCs thanks to their extremely high spatial resolution (~0.05arcsec). We report a study of proper motion of NGC 104, one of the most metal-rich Milky Way GCs, based-on archival images of NGC 104 observed using HST/ACS. Using the stars in Small Magellanic Cloud as reference coordinate, we are able to measure the proper motions of individual stars in NGC 104 with a high precision. We discuss the internal dynamics of stars in NGC 104 by comparing proper motion results based-on shorter (<1yr) and longer (~7yrs) time durations.

  • PDF

Monitoring in-service performance of fibre-reinforced foamed urethane sleepers/bearers in railway urban turnout systems

  • Kaewunruen, Sakdirat
    • Structural Monitoring and Maintenance
    • /
    • v.1 no.1
    • /
    • pp.131-157
    • /
    • 2014
  • Special track systems used to divert a train to other directions or other tracks are generally called 'railway turnout'. A traditional turnout system consists of steel rails, switches, crossings, steel plates, fasteners, screw spikes, timber bearers, ballast and formation. The wheel rail contact over the crossing transfer zone has a dip-like shape and can often cause detrimental impact loads on the railway track and its components. The large impact also emits disturbing noises (either impact or ground-borne noise) to railway neighbors. In a brown-field railway track where an existing aged infrastructure requires renewal or maintenance, some physical constraints and construction complexities may dominate the choice of track forms or certain components. With the difficulty to seek for high-quality timbers with dimensional stability, a methodology to replace aged timber bearers in harsh dynamic environments is to adopt an alternative material that could mimic responses and characteristics of timber in both static and dynamic loading conditions. A critical review has suggested an application of an alternative material called fibre-reinforced foamed urethane (FFU). The full-scale capacity design makes use of its comparable engineering characteristics to timber, high-impact attenuation, high damping property, and a longer service life. A field trial to investigate in-situ behaviours of a turnout grillage system using an alternative material, 'fibre-reinforced foamed urethane (FFU)' bearers, has been carried out at a complex turnout junction under heavy mixed traffics at Hornsby, New South Wales, Australia. The turnout junction was renewed using the FFU bearers altogether with new special track components. Influences of the FFU bearers on track geometry (recorded by track inspection vehicle 'AK Car'), track settlement (based on survey data), track dynamics, and acoustic characteristics have been measured. Operational train pass-by measurements have been analysed to evaluate the effectiveness of the replacement methodology. Comparative studies show that the use of FFU bearers generates higher rail and sleeper accelerations but the damping capacity of the FFU help suppress vibration transferring onto other track components. The survey data analysis suggests a small vertical settlement and negligible lateral movement of the turnout system. The static and dynamic behaviours of FFU bearers appear to equate that of natural timber but its service life is superior.

Features of Malignancy Prevalence among Children in the Aral Sea Region

  • Mamyrbayev, Arstan;Dyussembayeva, Nailya;Ibrayeva, Lyazzat;Satenova, Zhanna;Tulyayeva, Anara;Kireyeva, Nurgul;Zholmukhamedova, Dinara;Rybalkina, Dina;Yeleuov, Galymzhan;Yeleuov, Almasbek
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.17 no.12
    • /
    • pp.5217-5221
    • /
    • 2016
  • Objective: A study of primary cancer morbidity among children and subsequent calculation of average annual incidence were carried out for boys and girls, and young men and women in Kazakhstan. Methods: The investigated population lived in three areas of the Aral Sea region: designated catastrophe (Aral, Kazalt, Shalkar regions), crisis (Zhalagash, Karmakshy, Shiely regions), pre-crisis (Irgiz, Arys, Ulytau regions). Zhanaarka region of Karaganda oblast was applied as a control. Parameters were retrospective analyzed for the 10 years from 2004 to 2013. Result: The results indicate that indices of children cancer morbidity were slightly higher in the Aral Sea region than in the control district, but they were comparable with similar data from studies in other regions. In all areas of the Aral Sea region, except for Ulytau, primary cancer morbidity exceeded the control level by 1.3-2.7 times (4.7%000). Hematological malignancies, including solid tumors - tumors of musculoskeletal system and skin, digestive system, brain and central nervous system predominated. Stress levels in zones of the Aral Sea region were slightly higher in the crisis zone than in the catastrophe zone that can be explained by the phenomenon of wave-like dynamics of disease growth risk. Gender differences in characteristics of malignancy formation were not more pronounced in the studied region. Conclusion: Indices of children cancer are slightly higher in the Aral Sea region than in the control area of Kazakhstan, but they are comparable to results for other regions.