Transformation Mapping of Bubbles' 2-D Circular Shape to an Elliptical Shape Under Influence of a Magnetic Field in Pool Boiling in Microgravity Conditions
This is the presentation of my (short) PhD viva defended at Massey University in New Zealand. I am Charline Lormand, I have successfully defended my PhD thesis in Earth Sciences in March 2020. More specifically, my PhD thesis focused on the magmatic and ascent processes associated with explosive eruptions at the Tongariro Volcanic Centre in New Zealand. Feel free to get in touch with me for more details.
As a scientist/physicist I view microgravity as another system state parameter: in early stages, systems behavior was studied at standard temperature and pressure. Next, observations took place over an entire range. Significant scientific discoveries and engineering advances were made when observing systems at low temperatures or low pressures. There is an immense database of information specific to 1g. Microgravity would provide a second dataset to explore further values of gravity ranges...
As a pragmatic person (entrepreneur? business? maker?) I view microgravity as benefiting and improving life on Earth in almost every aspect of it as a result of the serendipitous and cascading effects originating in the new knowledge gained in space.
I hope the presentation speaks to this effect
Transformation Mapping of Bubbles' 2-D Circular Shape to an Elliptical Shape Under Influence of a Magnetic Field in Pool Boiling in Microgravity Conditions
This is the presentation of my (short) PhD viva defended at Massey University in New Zealand. I am Charline Lormand, I have successfully defended my PhD thesis in Earth Sciences in March 2020. More specifically, my PhD thesis focused on the magmatic and ascent processes associated with explosive eruptions at the Tongariro Volcanic Centre in New Zealand. Feel free to get in touch with me for more details.
As a scientist/physicist I view microgravity as another system state parameter: in early stages, systems behavior was studied at standard temperature and pressure. Next, observations took place over an entire range. Significant scientific discoveries and engineering advances were made when observing systems at low temperatures or low pressures. There is an immense database of information specific to 1g. Microgravity would provide a second dataset to explore further values of gravity ranges...
As a pragmatic person (entrepreneur? business? maker?) I view microgravity as benefiting and improving life on Earth in almost every aspect of it as a result of the serendipitous and cascading effects originating in the new knowledge gained in space.
I hope the presentation speaks to this effect
This paper presents the design of a deployable and
foldable tsunami pod for older and disabled people who cannot
run to higher grounds during a tsunami attack. In our design, we
adopt an ellipsoid structure and use finite element method (FEM)
to model the structure. Then, we conduct numerical simulation
and confirm the safety based on the von Mises equivalent value
and the Head Injury Criterion (HIC). As the result of the first
simulation, it is proved that the initial model referring to the
commercially available tsunami shelters is weak against the
impact force from rigid walls and obstacles and can be strained
in the central part. And also, the occupant might hit against the
internal wall and get injured. Therefore, a seat and upper and
lower bars are added to the initial model. As a result of the
second simulation, the von Mises equivalent value for the
modified model is decreased, but still above that of the first
simulation. The HIC value is decreased largely and is much less
than the HIC safety level. This is because the occupant restraint
system will prevent the occupant from hitting the internal wall of
the pod. Moreover, we optimize the structure for the tsunami pod
by minimizing its weight. Finally, we confirm the validity of the
optimal model in the original condition of fluid-structure
coupling analysis.
The purpose of this study is to design experiments to determine the impact of ship
aerodynamics in Indonesia using the Computational Fluid Dynamic method and
compare the impact of fuell consumption and load from experimental testing. Thus, it
can be known in detail about the voltage that occurs up to the final speed of the ship
during testing. In the preparation of this research the first step is to model the end of
the ship using CAD software from the original model used in experimental testing. The
next thing is to determine the value of the mechanical properties of the material and
then put it in the CAE software. In CAE software, it is also determined about the
boundary conditions of the material and then determines the speed. The next thing to
do is the process of meshing the plate and ammunition and after the meshing process
is proceeded to the running process. In contrast to experimental testing where there
are various obstacles, the data produced by testing the Computational Fluid Dynamic
method and experimental testing can sometimes be different. This is because in the
testing process using Computational Fluid Dynamic, conditions are always in optimal
conditions.
MODELING OF E. COLI TRANSPORT ON HOMOGENEOUS CLAY FORMATION INFLUENCED BY PER...IAEME Publication
Modeling of E.coli transport on homogenous clay influenced by permeability has been carried out. The transport of the microbes on uniform clay formation was developed to monitor the migration process of the microbes in the clay region. The model explains the behaviour of the microbes with respect to time of transport on homogenous clay, and determines the rate of concentration including the rate of permeability influence. The results show that without any regeneration of the microbes in the study area, the concentration at the period from 10 – 100 days may be insignificant on homogenous clay formation. From the simulation results it has explain the behaviour in physical process where the contaminant express it deposition from high to low concentration, while in other deposition the heterogeneous setting of some minerals developed high accumulation of E.coli in eighty days thus decreasing slightly in hundred days. The models were compared with the experimental values and both parameters compared favourably well.
Microthrusters are used to propel and orient small (miniature satellites). Various systems are developed till now. In this system there is a MEMS valve that opens or closes to operate the truster.
Effect of wind turbine on tlp floating platform responseseSAT Journals
Abstract Ever increasing population of India demands high production of electrical energy which puts immense pressure on our limited stock of non-renewable sources of energy and makes us dependent over imports from foreign countries. The present study focuses on the innovative concept of renewable offshore wind energy wherein the hydrodynamic analysis of Tension Leg Platform (TLP) Floating Offshore Wind Turbine (FOWT) which supports 5MW wind turbine tower is carried out using ‘ANSYS Workbench 14.5’. The six degree responses of the structure are obtained in operational conditions considering rated wind velocity of 11.4m/s in an irregular wave environment. Two cases are mainly considered, the first-one with incident wave and wind combined action along 00 (case 1) and the second–one with incident wave and wind combined action along 450 (case 2). The effect of wind turbine on TLP responses is compared in between 10 different geometric models; 5 models (A’, B’, C’, D’, E’) considering only the TLP platform and 5 models (A, B, C, D, E) considering the same platforms along with wind turbine tower. It is observed that TLP FOWT has higher translational motions (surge, sway, and heave) as compared to rotational motions (roll, pitch, and yaw). The metacentric height improves drastically after adding weight to concrete ballast. Higher reserve buoyancy helps reduce surge, sway, roll and yaw. The direction of the incident wave and wind does not affect heave response and remains same when incident wave and wind acts at 00 or 450. Higher reserve buoyancy increases pitch response only when incident wave and wind is acting at 00 but the reverse effect is observed when incident wave and wind is acting at 450. Keywords: TLP, floating offshore wind turbine, hydrodynamic analysis.
Experimental Research on Primary Wave Height Generated by Integral Landslide ...Agriculture Journal IJOEAR
Abstract—For investigating the primary wave height generated by integral landslide in channel type reservoir, by adopting orthogonal experimental method to design experiment groups. Landslides occurrence and the exchanges progress between landslides and water were simulated through the conceptual model experiment. Experiment result analysis and variance analysis obtained primary wave height with the variation of the influencing factors and significant trends. Theoretical analysis and experimental results are the same.
This paper presents the design of a deployable and
foldable tsunami pod for older and disabled people who cannot
run to higher grounds during a tsunami attack. In our design, we
adopt an ellipsoid structure and use finite element method (FEM)
to model the structure. Then, we conduct numerical simulation
and confirm the safety based on the von Mises equivalent value
and the Head Injury Criterion (HIC). As the result of the first
simulation, it is proved that the initial model referring to the
commercially available tsunami shelters is weak against the
impact force from rigid walls and obstacles and can be strained
in the central part. And also, the occupant might hit against the
internal wall and get injured. Therefore, a seat and upper and
lower bars are added to the initial model. As a result of the
second simulation, the von Mises equivalent value for the
modified model is decreased, but still above that of the first
simulation. The HIC value is decreased largely and is much less
than the HIC safety level. This is because the occupant restraint
system will prevent the occupant from hitting the internal wall of
the pod. Moreover, we optimize the structure for the tsunami pod
by minimizing its weight. Finally, we confirm the validity of the
optimal model in the original condition of fluid-structure
coupling analysis.
The purpose of this study is to design experiments to determine the impact of ship
aerodynamics in Indonesia using the Computational Fluid Dynamic method and
compare the impact of fuell consumption and load from experimental testing. Thus, it
can be known in detail about the voltage that occurs up to the final speed of the ship
during testing. In the preparation of this research the first step is to model the end of
the ship using CAD software from the original model used in experimental testing. The
next thing is to determine the value of the mechanical properties of the material and
then put it in the CAE software. In CAE software, it is also determined about the
boundary conditions of the material and then determines the speed. The next thing to
do is the process of meshing the plate and ammunition and after the meshing process
is proceeded to the running process. In contrast to experimental testing where there
are various obstacles, the data produced by testing the Computational Fluid Dynamic
method and experimental testing can sometimes be different. This is because in the
testing process using Computational Fluid Dynamic, conditions are always in optimal
conditions.
MODELING OF E. COLI TRANSPORT ON HOMOGENEOUS CLAY FORMATION INFLUENCED BY PER...IAEME Publication
Modeling of E.coli transport on homogenous clay influenced by permeability has been carried out. The transport of the microbes on uniform clay formation was developed to monitor the migration process of the microbes in the clay region. The model explains the behaviour of the microbes with respect to time of transport on homogenous clay, and determines the rate of concentration including the rate of permeability influence. The results show that without any regeneration of the microbes in the study area, the concentration at the period from 10 – 100 days may be insignificant on homogenous clay formation. From the simulation results it has explain the behaviour in physical process where the contaminant express it deposition from high to low concentration, while in other deposition the heterogeneous setting of some minerals developed high accumulation of E.coli in eighty days thus decreasing slightly in hundred days. The models were compared with the experimental values and both parameters compared favourably well.
Microthrusters are used to propel and orient small (miniature satellites). Various systems are developed till now. In this system there is a MEMS valve that opens or closes to operate the truster.
Effect of wind turbine on tlp floating platform responseseSAT Journals
Abstract Ever increasing population of India demands high production of electrical energy which puts immense pressure on our limited stock of non-renewable sources of energy and makes us dependent over imports from foreign countries. The present study focuses on the innovative concept of renewable offshore wind energy wherein the hydrodynamic analysis of Tension Leg Platform (TLP) Floating Offshore Wind Turbine (FOWT) which supports 5MW wind turbine tower is carried out using ‘ANSYS Workbench 14.5’. The six degree responses of the structure are obtained in operational conditions considering rated wind velocity of 11.4m/s in an irregular wave environment. Two cases are mainly considered, the first-one with incident wave and wind combined action along 00 (case 1) and the second–one with incident wave and wind combined action along 450 (case 2). The effect of wind turbine on TLP responses is compared in between 10 different geometric models; 5 models (A’, B’, C’, D’, E’) considering only the TLP platform and 5 models (A, B, C, D, E) considering the same platforms along with wind turbine tower. It is observed that TLP FOWT has higher translational motions (surge, sway, and heave) as compared to rotational motions (roll, pitch, and yaw). The metacentric height improves drastically after adding weight to concrete ballast. Higher reserve buoyancy helps reduce surge, sway, roll and yaw. The direction of the incident wave and wind does not affect heave response and remains same when incident wave and wind acts at 00 or 450. Higher reserve buoyancy increases pitch response only when incident wave and wind is acting at 00 but the reverse effect is observed when incident wave and wind is acting at 450. Keywords: TLP, floating offshore wind turbine, hydrodynamic analysis.
Experimental Research on Primary Wave Height Generated by Integral Landslide ...Agriculture Journal IJOEAR
Abstract—For investigating the primary wave height generated by integral landslide in channel type reservoir, by adopting orthogonal experimental method to design experiment groups. Landslides occurrence and the exchanges progress between landslides and water were simulated through the conceptual model experiment. Experiment result analysis and variance analysis obtained primary wave height with the variation of the influencing factors and significant trends. Theoretical analysis and experimental results are the same.
This pdf is about the Schizophrenia.
For more details visit on YouTube; @SELF-EXPLANATORY;
https://www.youtube.com/channel/UCAiarMZDNhe1A3Rnpr_WkzA/videos
Thanks...!
Richard's aventures in two entangled wonderlandsRichard Gill
Since the loophole-free Bell experiments of 2020 and the Nobel prizes in physics of 2022, critics of Bell's work have retreated to the fortress of super-determinism. Now, super-determinism is a derogatory word - it just means "determinism". Palmer, Hance and Hossenfelder argue that quantum mechanics and determinism are not incompatible, using a sophisticated mathematical construction based on a subtle thinning of allowed states and measurements in quantum mechanics, such that what is left appears to make Bell's argument fail, without altering the empirical predictions of quantum mechanics. I think however that it is a smoke screen, and the slogan "lost in math" comes to my mind. I will discuss some other recent disproofs of Bell's theorem using the language of causality based on causal graphs. Causal thinking is also central to law and justice. I will mention surprising connections to my work on serial killer nurse cases, in particular the Dutch case of Lucia de Berk and the current UK case of Lucy Letby.
Professional air quality monitoring systems provide immediate, on-site data for analysis, compliance, and decision-making.
Monitor common gases, weather parameters, particulates.
Multi-source connectivity as the driver of solar wind variability in the heli...Sérgio Sacani
The ambient solar wind that flls the heliosphere originates from multiple
sources in the solar corona and is highly structured. It is often described
as high-speed, relatively homogeneous, plasma streams from coronal
holes and slow-speed, highly variable, streams whose source regions are
under debate. A key goal of ESA/NASA’s Solar Orbiter mission is to identify
solar wind sources and understand what drives the complexity seen in the
heliosphere. By combining magnetic feld modelling and spectroscopic
techniques with high-resolution observations and measurements, we show
that the solar wind variability detected in situ by Solar Orbiter in March
2022 is driven by spatio-temporal changes in the magnetic connectivity to
multiple sources in the solar atmosphere. The magnetic feld footpoints
connected to the spacecraft moved from the boundaries of a coronal hole
to one active region (12961) and then across to another region (12957). This
is refected in the in situ measurements, which show the transition from fast
to highly Alfvénic then to slow solar wind that is disrupted by the arrival of
a coronal mass ejection. Our results describe solar wind variability at 0.5 au
but are applicable to near-Earth observatories.
Cancer cell metabolism: special Reference to Lactate PathwayAADYARAJPANDEY1
Normal Cell Metabolism:
Cellular respiration describes the series of steps that cells use to break down sugar and other chemicals to get the energy we need to function.
Energy is stored in the bonds of glucose and when glucose is broken down, much of that energy is released.
Cell utilize energy in the form of ATP.
The first step of respiration is called glycolysis. In a series of steps, glycolysis breaks glucose into two smaller molecules - a chemical called pyruvate. A small amount of ATP is formed during this process.
Most healthy cells continue the breakdown in a second process, called the Kreb's cycle. The Kreb's cycle allows cells to “burn” the pyruvates made in glycolysis to get more ATP.
The last step in the breakdown of glucose is called oxidative phosphorylation (Ox-Phos).
It takes place in specialized cell structures called mitochondria. This process produces a large amount of ATP. Importantly, cells need oxygen to complete oxidative phosphorylation.
If a cell completes only glycolysis, only 2 molecules of ATP are made per glucose. However, if the cell completes the entire respiration process (glycolysis - Kreb's - oxidative phosphorylation), about 36 molecules of ATP are created, giving it much more energy to use.
IN CANCER CELL:
Unlike healthy cells that "burn" the entire molecule of sugar to capture a large amount of energy as ATP, cancer cells are wasteful.
Cancer cells only partially break down sugar molecules. They overuse the first step of respiration, glycolysis. They frequently do not complete the second step, oxidative phosphorylation.
This results in only 2 molecules of ATP per each glucose molecule instead of the 36 or so ATPs healthy cells gain. As a result, cancer cells need to use a lot more sugar molecules to get enough energy to survive.
Unlike healthy cells that "burn" the entire molecule of sugar to capture a large amount of energy as ATP, cancer cells are wasteful.
Cancer cells only partially break down sugar molecules. They overuse the first step of respiration, glycolysis. They frequently do not complete the second step, oxidative phosphorylation.
This results in only 2 molecules of ATP per each glucose molecule instead of the 36 or so ATPs healthy cells gain. As a result, cancer cells need to use a lot more sugar molecules to get enough energy to survive.
introduction to WARBERG PHENOMENA:
WARBURG EFFECT Usually, cancer cells are highly glycolytic (glucose addiction) and take up more glucose than do normal cells from outside.
Otto Heinrich Warburg (; 8 October 1883 – 1 August 1970) In 1931 was awarded the Nobel Prize in Physiology for his "discovery of the nature and mode of action of the respiratory enzyme.
WARNBURG EFFECT : cancer cells under aerobic (well-oxygenated) conditions to metabolize glucose to lactate (aerobic glycolysis) is known as the Warburg effect. Warburg made the observation that tumor slices consume glucose and secrete lactate at a higher rate than normal tissues.
(May 29th, 2024) Advancements in Intravital Microscopy- Insights for Preclini...Scintica Instrumentation
Intravital microscopy (IVM) is a powerful tool utilized to study cellular behavior over time and space in vivo. Much of our understanding of cell biology has been accomplished using various in vitro and ex vivo methods; however, these studies do not necessarily reflect the natural dynamics of biological processes. Unlike traditional cell culture or fixed tissue imaging, IVM allows for the ultra-fast high-resolution imaging of cellular processes over time and space and were studied in its natural environment. Real-time visualization of biological processes in the context of an intact organism helps maintain physiological relevance and provide insights into the progression of disease, response to treatments or developmental processes.
In this webinar we give an overview of advanced applications of the IVM system in preclinical research. IVIM technology is a provider of all-in-one intravital microscopy systems and solutions optimized for in vivo imaging of live animal models at sub-micron resolution. The system’s unique features and user-friendly software enables researchers to probe fast dynamic biological processes such as immune cell tracking, cell-cell interaction as well as vascularization and tumor metastasis with exceptional detail. This webinar will also give an overview of IVM being utilized in drug development, offering a view into the intricate interaction between drugs/nanoparticles and tissues in vivo and allows for the evaluation of therapeutic intervention in a variety of tissues and organs. This interdisciplinary collaboration continues to drive the advancements of novel therapeutic strategies.
1. Studying the Characteristics of Bubble Motion in Pool
Boiling in Microgravity Conditions Under the Influence
of a Magnetic Field.
by
Thilanka Munasinghe
West Virginia University,
Morgantown, USA
thilanka.munasinghe@mail.wvu.edu.
RAST 2009 - Istanbul ,Turkey 1
2. The “Key” Terms :
• Pool Boiling
• Microgravity
• Bubble characteristics
•
RAST 2009 - Istanbul ,Turkey 2
3. What is Pool Boiling ?
How can we do pool boiling ?
Pool Boling is a method of boiling and generating bubbles in a
liquid that can boil in a container with a heat resource.
There are several ways that can do the pool boiling and one of
the common ways is boiling in a cylindrical tank as we used in
our experiment.
RAST 2009 - Istanbul ,Turkey 3
4. What is “Microgravity” ?
micro level (10-6) = μ = 0.000001
g= 9.81 m/s2 ( Earth’s gravity level)
μ g= [0.000001] X [ 9.81 ]
= 0.00000981 m/s2
RAST 2009 - Istanbul ,Turkey 4
5. Pool Boiling in two identical tanks with a
paramagnetic liquid
Paramagnetic liquid – MnCl2 (aq) + H2O
RAST 2009 - Istanbul ,Turkey 5
6. Why We need a Paramagnetic Liquid?
In order to avoid the floating of the liquid inside the tank
due to lack of gravity, paramagnetic liquid will be used
to attach the liquid to the bottom surface of the tank by
using a permanent magnet.
RAST 2009 - Istanbul ,Turkey 6
7. Bubble Behavior
• Bubble’s travel path inside the tank.
• Size of the bubble ( vertical and horizontal radius).
• Bubble’s shape deformation comparatively to the
original shape.
RAST 2009 - Istanbul ,Turkey 7
8. How to create a “Microgravity”
conditions artificially ?
Parabolic path of an aircraft can create
“Microgravity” conditions within a short period of
time such as 20-30 seconds period in a one
parabola.
RAST 2009 - Istanbul ,Turkey 8
9. Parabolic path of the aircraft that can create
microgravity conditionRAST 2009 - Istanbul ,Turkey 9
29. Bubble’s coordinates on the perimeter
Three consecutive bubble frames
RAST 2009 - Istanbul ,Turkey 29
30. Colour Images has converted to gray scale images and bubble location has determined.
(1) Colour image and Gray scale image
(2) Location of the bubble on gray scale image with respect to the colour image
(1) (2)
RAST 2009 - Istanbul ,Turkey 30
31. 0 0.02 0.04 0.06 0.08 0.1
0
500
1000
1500
2000
2500
3000
3500
Axial Distance Vs Magnetic Feild Strength
Axial Distance (m)
MagneticFeildStrength(Gauss)
RAST 2009 - Istanbul ,Turkey 31
32. 40 45 50 55 60 65
0
5
10
15
20
25
30
35
40
45
50
Bubble Possition Vs Frame Number
Frame Number
X-CoordinateoftheBubblePossition(pixels)
RAST 2009 - Istanbul ,Turkey 32
33. 0 10 20 30 40 50
20
40
60
80
100
120
140
160
180
200
220
Vertical Possition of the Bubble Vs Frame Number
Frame Number
Y-CoordinateoftheBubblePossition(pixels)
RAST 2009 - Istanbul ,Turkey 33
34. 0 5 10 15 20 25 30 35 40 45 50
6
8
10
12
14
16
18
20
22
Radius Vs Frame Number
Frame Number
BubbleRadius(pixels)
Vertical Radius
Horizontal Radius
RAST 2009 - Istanbul ,Turkey 34
35. 0 5 10 15 20 25 30 35 40 45 50
0
200
400
600
800
1000
1200
1400
Frame Number
BubbleArea(pixelsquard)
RAST 2009 - Istanbul ,Turkey 35
36. Possible practical applications of Pool
Boiling in microgravity
• Pool boiling in Microgravity conditions can use as a
“Cooling Process” for out of Earth conditions specially inside
the ISS (International Space Station)
• Space applications that are related to liquids and bubbles
that related to many fields such as Space medicine, Space
Agriculture, Heat transfer ..etc
RAST 2009 - Istanbul ,Turkey 36
37. Conclusion:
• In microgravity conditions boiling process take place faster than Earth’s gravity.
• At the bottom of the tank the bubble’s vertical radius is comparatively smaller than
the horizontal radius.
•As the bubble goes along the tank, the strength of the magnetic field reduces and
eventually the vertical component of the radius gets bigger than the horizontal radius.
•While the bubble travels upwards, bubble movement demonstrates a 2-D spiral path
along the tank.
•Horizontal and vertical radius, bubble area, bubble path along the vertical axis of the
tank was graphed verses bubble frame number for the detailed characteristic study of
bubbles.
•These bubbles also were observed to be elliptical and in real visualization it is in 3-D.
RAST 2009 - Istanbul ,Turkey 37
38. A. Fujiwara, Y. Danmoto, K. Hishida, “Bubble Deformation and Surrounding Flow
Structure Measured By PIV/LIV and Shadow image Technique”, ASME_JSME 4th Joint
Fluid Engineering Conference, F E DSM200 3-4 5674, Honolulu, Hawaii, USA, July
2003.
S. Toshiyuki, M. Watanabe,T. Fukano, “Study On Single Bubble Chain in Stagnant
Water”, ASME_JSME 4th Joint Fluid Engineering Conference, F E DSM200 3-4 5381,
Honolulu, Hawaii, USA, July 2003.
M. Ashihara, A. Kitagawa, M. Ishikawa, A. Nakashinchi, Y. Murai, F Yamamoto,
“Particle Tracking Velocimetry Measurement of Bubble-Bubble Interaction”,
ASME_JSME 4th Joint Fluid Engineering Conference, F E DSM200 3-4 5208,
Honolulu, Hawaii, USA, July 2003.
T. Munasinghe, “Investigating the Bubble Behavior in Pool Boiling in Microgravity
Conditions,” WCE 2008, vol. II, pp. 1366–1371, London, UK, July 2008.
C. Maneri, P Vassallo, “Dynamic of Bubble Rising in Finite and Infinite Media”
ASME_JSME 4th Joint Fluid Engineering Conference, F E DSM200 3-4 5208,
Honolulu, Hawaii, USA, July 2003.
Reference :
RAST 2009 - Istanbul ,Turkey 38
39. Acknowledgement
Special Thanks to:
NASA -West Virginia Space Grant
Consortium at WVU.
West Virginia University, College of
Engineering and Mineral Recourse.
Mechanical and Aerospace Engineering
Department of WVU.
Dr. John Kuhlman , Dr. Donald Gray,
Dr. Majid Jaraiedi , Dr. Arun Ross and
Microgravity Research Team.
Zero Gravity Cooperation.
RAST 2009 - Istanbul ,Turkey 39