Method of calculation for three-dimensional joint torque in human movement in a linked rigid body system

OpenAIRE

宮西, 智久; Tomohisa, Miyanishi; 仙台大学; Sendai College

1998-01-01

In sports biomechanics, joint torque analysis play a very important role. For this reason, if we understand the joint torque during sports activity, it will be useful for the diagnosis and/or evaluation of sports technique, the specific method for muscle training and the mechanisms of sports movement. In the past decade, many studies which dealt with the motion analysis for sports activity using a three-dimensional cinematography, have been done. However, most of these studies has been focuse...

Characterization of an Actively Controlled Three-Dimensional Turret Wake

Science.gov (United States)

Shea, Patrick; Glauser, Mark

2012-11-01

Three-dimensional turrets are commonly used for housing optical systems on airborne platforms. As bluff bodies, these geometries generate highly turbulent wakes that decrease the performance of the optical systems and the aircraft. The current experimental study looked to use dynamic suction in both open and closed-loop control configurations to actively control the turret wake. The flow field was characterized using dynamic pressure and stereoscopic PIV measurements in the wake of the turret. Results showed that the suction system was able to manipulate the wake region of the turret and could alter not only the spatial structure of the wake, but also the temporal behavior of the wake flow field. Closed-loop, feedback control techniques were used to determine a more optimal control input for the flow control. Similar control effects were seen for both the steady open-loop control case and the closed-loop feedback control configuration with a 45% reduction in the suction levels when comparing the closed-loop to the open-loop case. These results provide unique information regarding the development of the baseline three-dimensional wake and the wake with three different active flow control configurations.

Self-assembled three-dimensional chiral colloidal architecture

Science.gov (United States)

Ben Zion, Matan Yah; He, Xiaojin; Maass, Corinna C.; Sha, Ruojie; Seeman, Nadrian C.; Chaikin, Paul M.

2017-11-01

Although stereochemistry has been a central focus of the molecular sciences since Pasteur, its province has previously been restricted to the nanometric scale. We have programmed the self-assembly of micron-sized colloidal clusters with structural information stemming from a nanometric arrangement. This was done by combining DNA nanotechnology with colloidal science. Using the functional flexibility of DNA origami in conjunction with the structural rigidity of colloidal particles, we demonstrate the parallel self-assembly of three-dimensional microconstructs, evincing highly specific geometry that includes control over position, dihedral angles, and cluster chirality.

Modelling three-dimensional distribution of photosynthetically active radiation in sloping coniferous stands

International Nuclear Information System (INIS)

Knyazikhin, Yu.; Kranigk, J.; Miessen, G.; Panfyorov, O.; Vygodskaya, N.; Gravenhorst, G.

1996-01-01

Solar irradiance is a major environmental factor governing biological and physiological processes in a vegetation canopy. Solar radiation distribution in a canopy and its effect are three-dimensional in nature. However, most of the radiation models up to now have been one-dimensional. They can be successfully applied to large-scale studies of forest functioning. The one-dimensional modelling technique, however, does not provide adequate interpretation of small scale processes leading to forest growth. In this article we discuss a modelling strategy for the simulation of three-dimensional radiation distribution in a vegetation canopy of a small area (about 0.25–0.3 ha). We demonstrate its realisation to predict the three-dimensional radiative regime of phytosynthetically active radiation in a real coniferous stand located on hilly surroundings. Our model can be used to investigate the influence of different climatic conditions, forest management methods and field sites on the solar energy available for forest growth in small heterogeneous areas. Further, a three-dimensional process-oriented model helps to derive global variables affecting bio-physiological processes in a vegetation canopy shifting from small scale studies of the functioning of forests to regional, continental, and global scale problems. (author)

Kinematics of swimming of the manta ray: three-dimensional analysis of open-water maneuverability.

Science.gov (United States)

Fish, Frank E; Kolpas, Allison; Crossett, Andrew; Dudas, Michael A; Moored, Keith W; Bart-Smith, Hilary

2018-03-22

For aquatic animals, turning maneuvers represent a locomotor activity that may not be confined to a single coordinate plane, making analysis difficult, particularly in the field. To measure turning performance in a three-dimensional space for the manta ray ( Mobula birostris ), a large open-water swimmer, scaled stereo video recordings were collected. Movements of the cephalic lobes, eye and tail base were tracked to obtain three-dimensional coordinates. A mathematical analysis was performed on the coordinate data to calculate the turning rate and curvature (1/turning radius) as a function of time by numerically estimating the derivative of manta trajectories through three-dimensional space. Principal component analysis was used to project the three-dimensional trajectory onto the two-dimensional turn. Smoothing splines were applied to these turns. These are flexible models that minimize a cost function with a parameter controlling the balance between data fidelity and regularity of the derivative. Data for 30 sequences of rays performing slow, steady turns showed the highest 20% of values for the turning rate and smallest 20% of turn radii were 42.65±16.66 deg s -1 and 2.05±1.26 m, respectively. Such turning maneuvers fall within the range of performance exhibited by swimmers with rigid bodies. © 2018. Published by The Company of Biologists Ltd.

Active immobilization of biomolecules on a hybrid three-dimensional nanoelectrode by dielectrophoresis for single-biomolecule study

International Nuclear Information System (INIS)

Yamamoto, Takatoki; Fujii, Teruo

2007-01-01

We propose and experimentally demonstrate a method of active immobilization for biomolecules on a three-dimensional nanometre-scale electrode (3D nanoelectrode) using dielectrophoresis to immobilize the biomolecules at predetermined locations for single-biomolecule study. We have developed a novel two-step fabrication process for obtaining a 3D nanoelectrode having a sharp top, which is necessary for immobilizing a single biomolecule at a single point. The first step is to fabricate the backbone structure, which is rigid and defines the shape of the 3D nanoelectrode. It was fabricated with diamond-like carbon (DLC) obtained using focused ion beam assisted chemical vapour deposition followed by post-plasma etching, which reshapes the DLC structure. The second step coats the DLC structure with a thin layer of aluminium, which supplies electrical conductivity to the DLC structure. By applying a high frequency (of the order of megahertz) and high intensity (greater than or equal to a few megavolts per metre) electric field using the 3D nanoelectrodes, the generated dielectrophoresis attracted and then immobilized target biomolecules onto the tops of 3D nanoelectrodes, as a demonstration of active immobilization of biomolecules

Three-dimensional neuroimaging

International Nuclear Information System (INIS)

Toga, A.W.

1990-01-01

This book reports on new neuroimaging technologies that are revolutionizing the study of the brain be enabling investigators to visualize its structure and entire pattern of functional activity in three dimensions. The book provides a theoretical and practical explanation of the new science of creating three-dimensional computer images of the brain. The coverage includes a review of the technology and methodology of neuroimaging, the instrumentation and procedures, issues of quantification, analytic protocols, and descriptions of neuroimaging systems. Examples are given to illustrate the use of three-dimensional enuroimaging to quantitate spatial measurements, perform analysis of autoradiographic and histological studies, and study the relationship between brain structure and function

Nanofluidic structures with complex three-dimensional surfaces

International Nuclear Information System (INIS)

Stavis, Samuel M; Gaitan, Michael; Strychalski, Elizabeth A

2009-01-01

Nanofluidic devices have typically explored a design space of patterns limited by a single nanoscale structure depth. A method is presented here for fabricating nanofluidic structures with complex three-dimensional (3D) surfaces, utilizing a single layer of grayscale photolithography and standard integrated circuit manufacturing tools. This method is applied to construct nanofluidic devices with numerous (30) structure depths controlled from ∼10 to ∼620 nm with an average standard deviation of 1 cm. A prototype 3D nanofluidic device is demonstrated that implements size exclusion of rigid nanoparticles and variable nanoscale confinement and deformation of biomolecules.

Dimensional Metrology of Non-rigid Parts Without Specialized Inspection Fixtures =

Science.gov (United States)

Sabri, Vahid

Quality control is an important factor for manufacturing companies looking to prosper in an era of globalization, market pressures and technological advances. Functionality and product quality cannot be guaranteed without this important aspect. Manufactured parts have deviations from their nominal (CAD) shape caused by the manufacturing process. Thus, geometric inspection is a very important element in the quality control of mechanical parts. We will focus here on the geometric inspection of non-rigid (flexible) parts which are widely used in the aeronautic and automotive industries. Non-rigid parts can have different forms in a free-state condition compared with their nominal models due to residual stress and gravity loads. To solve this problem, dedicated inspection fixtures are generally used in industry to compensate for the displacement of such parts for simulating the use state in order to perform geometric inspections. These fixtures and the installation and inspection processes are expensive and time-consuming. Our aim in this thesis is therefore to develop an inspection method which eliminates the need for specialized fixtures. This is done by acquiring a point cloud from the part in a free-state condition using a contactless measuring device such as optical scanning and comparing it with the CAD model for the deviation identification. Using a non-rigid registration method and finite element analysis, we numerically inspect the profile of a non-rigid part. To do so, a simulated displacement is performed using an improved definition of displacement boundary conditions for simulating unfixed parts. In addition, we propose a numerical method for dimensional metrology of non-rigid parts in a free-state condition based on the arc length measurement by calculating the geodesic distance using the Fast Marching Method (FMM). In this thesis, we apply our developed methods on industrial non-rigid parts with free-form surfaces simulated with different types of

Tailor-made three-dimensional hybrid scaffolds for cell cultures

International Nuclear Information System (INIS)

Psycharakis, Stylianos; Melissinaki, Vasileia; Giakoumaki, Anastasia; Ranella, Anthi; Tosca, Androniki

2011-01-01

The construction of the ideal three-dimensional scaffold for cell culture is one of the most intriguing topics in tissue engineering. It has been shown that cells can be cultured on most organic biomimetic materials, which now are losing popularity in favour of novel, hybrid systems. In this study, a series of photosensitive sol-gel hybrid materials, based on silicon-zirconium and silicon-titanium oxides, have been investigated for their suitability in three-dimensional scaffold fabrication. These materials can be structured by two-photon polymerization, a laser-based technique allowing the fabrication of micrometre-size structures with submicron resolution. The work presented here examined the effect of the organic/inorganic composition of the materials on cell behaviour and the establishment of a 'cell-culture friendly' environment. This is vital for cell adhesion, growth and differentiation, as the organic part of the material provides the soft matrix for cell growth, whereas the inorganic component gives the mechanical stability and rigidity of the three-dimensional structures. In addition, the use of femtosecond laser structuring permits the fabrication of a wide range of mechanically stable scaffolds of different sizes and shapes to be tested in terms of cell viability, proliferation and orientation.

Removing grain boundaries from three-dimensional colloidal crystals using active dopants

NARCIS (Netherlands)

van der Meer, B.; Dijkstra, M.; Filion, L.C.

2016-01-01

Using computer simulations we explore how grain boundaries can be removed from three-dimensional colloidal crystals by doping with a small fraction of active colloids. We show that for sufficient selfpropulsion, the system is driven into a crystal-fluid coexistence. In this phase separated regime,

A computer-based biomechanical analysis of the three-dimensional motion of cementless hip prostheses.

Science.gov (United States)

Gilbert, J L; Bloomfeld, R S; Lautenschlager, E P; Wixson, R L

1992-04-01

A computer-based mathematical technique was developed to measure and completely describe the migration and micromotion of a femoral hip prosthesis relative to the femur. This technique utilized the mechanics of rigid-body motion analysis and apparatus of seven linear displacement transducers to measure and describe the complete three-dimensional motion of the prosthesis during cyclic loading. Computer acquisition of the data and custom analysis software allowed one to calculate the magnitude and direction of the motion of any point of interest on the prostheses from information about the motion of two points on the device. The data were also used to replay the tests using a computer animation technique, which allowed a magnified view of the three-dimensional motion of the prosthesis. This paper describes the mathematical development of the rigid-body motion analysis, the experimental method and apparatus for data collection, the technique used to animate the motion, the sources of error and the effect of the assumptions (rigid bodies) on the results. Selected results of individual test runs of uncemented and cemented prostheses are presented to demonstrate the efficacy of the method. The combined effect of the vibration and electrical noise resulted in a resolution of the system of about 3-5 microns motion for each transducer. Deformation effects appear to contribute about 3-15 microns to the measurement error. This measurement and analysis technique is a very sensitive and powerful means of assessing the effects of different design parameters on the migration and micromotion of total joint prostheses and can be applied to any other case (knee, dental implant) where three-dimensional relative motion between two bodies is important.

Three dimensional illustrating - three-dimensional vision and deception of sensibility

Directory of Open Access Journals (Sweden)

Anita Gánóczy

2009-03-01

Full Text Available The wide-spread digital photography and computer use gave the opportunity for everyone to make three-dimensional pictures and to make them public. The new opportunities with three-dimensional techniques give chance for the birth of new artistic photographs. We present in detail the biological roots of three-dimensional visualization, the phenomena of movement parallax, which can be used efficiently in making three-dimensional graphics, the Zöllner- and Corridor-illusion. There are present in this paper the visual elements, which contribute to define a plane two-dimensional image in three-dimension: coherent lines, the covering, the measurement changes, the relative altitude state, the abatement of detail profusion, the shadings and the perspective effects of colors.

Tailor-made three-dimensional hybrid scaffolds for cell cultures

Energy Technology Data Exchange (ETDEWEB)

Psycharakis, Stylianos; Melissinaki, Vasileia; Giakoumaki, Anastasia; Ranella, Anthi [Institute of Electronic Structure and Laser, Foundation for Research and Technology Hellas, PO Box 1527, 711 10 Heraklion, Crete (Greece); Tosca, Androniki, E-mail: ranthi@iesl.forth.gr [Department of Medicine, University of Crete, 710 03 Heraklion, Crete (Greece)

2011-08-15

The construction of the ideal three-dimensional scaffold for cell culture is one of the most intriguing topics in tissue engineering. It has been shown that cells can be cultured on most organic biomimetic materials, which now are losing popularity in favour of novel, hybrid systems. In this study, a series of photosensitive sol-gel hybrid materials, based on silicon-zirconium and silicon-titanium oxides, have been investigated for their suitability in three-dimensional scaffold fabrication. These materials can be structured by two-photon polymerization, a laser-based technique allowing the fabrication of micrometre-size structures with submicron resolution. The work presented here examined the effect of the organic/inorganic composition of the materials on cell behaviour and the establishment of a 'cell-culture friendly' environment. This is vital for cell adhesion, growth and differentiation, as the organic part of the material provides the soft matrix for cell growth, whereas the inorganic component gives the mechanical stability and rigidity of the three-dimensional structures. In addition, the use of femtosecond laser structuring permits the fabrication of a wide range of mechanically stable scaffolds of different sizes and shapes to be tested in terms of cell viability, proliferation and orientation.

Three-dimensional reconstruction of functional brain images

International Nuclear Information System (INIS)

Inoue, Masato; Shoji, Kazuhiko; Kojima, Hisayoshi; Hirano, Shigeru; Naito, Yasushi; Honjo, Iwao

1999-01-01

We consider PET (positron emission tomography) measurement with SPM (Statistical Parametric Mapping) analysis to be one of the most useful methods to identify activated areas of the brain involved in language processing. SPM is an effective analytical method that detects markedly activated areas over the whole brain. However, with the conventional presentations of these functional brain images, such as horizontal slices, three directional projection, or brain surface coloring, makes understanding and interpreting the positional relationships among various brain areas difficult. Therefore, we developed three-dimensionally reconstructed images from these functional brain images to improve the interpretation. The subjects were 12 normal volunteers. The following three types of images were constructed: routine images by SPM, three-dimensional static images, and three-dimensional dynamic images, after PET images were analyzed by SPM during daily dialog listening. The creation of images of both the three-dimensional static and dynamic types employed the volume rendering method by VTK (The Visualization Toolkit). Since the functional brain images did not include original brain images, we synthesized SPM and MRI brain images by self-made C++ programs. The three-dimensional dynamic images were made by sequencing static images with available software. Images of both the three-dimensional static and dynamic types were processed by a personal computer system. Our newly created images showed clearer positional relationships among activated brain areas compared to the conventional method. To date, functional brain images have been employed in fields such as neurology or neurosurgery, however, these images may be useful even in the field of otorhinolaryngology, to assess hearing and speech. Exact three-dimensional images based on functional brain images are important for exact and intuitive interpretation, and may lead to new developments in brain science. Currently, the surface

Three-dimensional reconstruction of functional brain images

Energy Technology Data Exchange (ETDEWEB)

Inoue, Masato; Shoji, Kazuhiko; Kojima, Hisayoshi; Hirano, Shigeru; Naito, Yasushi; Honjo, Iwao [Kyoto Univ. (Japan)

1999-08-01

We consider PET (positron emission tomography) measurement with SPM (Statistical Parametric Mapping) analysis to be one of the most useful methods to identify activated areas of the brain involved in language processing. SPM is an effective analytical method that detects markedly activated areas over the whole brain. However, with the conventional presentations of these functional brain images, such as horizontal slices, three directional projection, or brain surface coloring, makes understanding and interpreting the positional relationships among various brain areas difficult. Therefore, we developed three-dimensionally reconstructed images from these functional brain images to improve the interpretation. The subjects were 12 normal volunteers. The following three types of images were constructed: routine images by SPM, three-dimensional static images, and three-dimensional dynamic images, after PET images were analyzed by SPM during daily dialog listening. The creation of images of both the three-dimensional static and dynamic types employed the volume rendering method by VTK (The Visualization Toolkit). Since the functional brain images did not include original brain images, we synthesized SPM and MRI brain images by self-made C++ programs. The three-dimensional dynamic images were made by sequencing static images with available software. Images of both the three-dimensional static and dynamic types were processed by a personal computer system. Our newly created images showed clearer positional relationships among activated brain areas compared to the conventional method. To date, functional brain images have been employed in fields such as neurology or neurosurgery, however, these images may be useful even in the field of otorhinolaryngology, to assess hearing and speech. Exact three-dimensional images based on functional brain images are important for exact and intuitive interpretation, and may lead to new developments in brain science. Currently, the surface

Rigidity of Glasses and Macromolecules

Science.gov (United States)

Thorpe, M. F.

1998-03-01

The simple yet powerful ideas of percolation theory have found their way into many different areas of research. In this talk we show how RIGIDITY PERCOLATION can be studied at a similar level of sophistication, using a powerful new program THE PEBBLE GAME (D. J. Jacobs and M. F. Thorpe, Phys. Rev. E) 53, 3682 (1996). that uses an integer algorithm. This program can analyse the rigidity of two and three dimensional networks containing more than one million bars and joints. We find the total number of floppy modes, and find the critical behavior as the network goes from floppy to rigid as more bars are added. We discuss the relevance of this work to network glasses, and how it relates to experiments that involve the mechanical properties like hardness and elasticity of covalent glassy networks like Ge_xAs_ySe_1-x-y and dicuss recent experiments that suggest that the rigidity transition may be first order (Xingwei Feng, W. J.Bresser and P. Boolchand, Phys. Rev. Lett 78), 4422 (1997).. This approach is also useful in macromolecules and proteins, where detailed information about the rigid domain structure can be obtained.

Three-dimensional neural cultures produce networks that mimic native brain activity.

Science.gov (United States)

Bourke, Justin L; Quigley, Anita F; Duchi, Serena; O'Connell, Cathal D; Crook, Jeremy M; Wallace, Gordon G; Cook, Mark J; Kapsa, Robert M I

2018-02-01

Development of brain function is critically dependent on neuronal networks organized through three dimensions. Culture of central nervous system neurons has traditionally been limited to two dimensions, restricting growth patterns and network formation to a single plane. Here, with the use of multichannel extracellular microelectrode arrays, we demonstrate that neurons cultured in a true three-dimensional environment recapitulate native neuronal network formation and produce functional outcomes more akin to in vivo neuronal network activity. Copyright © 2017 John Wiley & Sons, Ltd.

Identifying Floppy and Rigid Regions in Proteins

Science.gov (United States)

Jacobs, D. J.; Thorpe, M. F.; Kuhn, L. A.

1998-03-01

In proteins it is possible to separate hard covalent forces involving bond lengths and bond angles from other weak forces. We model the microstructure of the protein as a generic bar-joint truss framework, where the hard covalent forces and strong hydrogen bonds are regarded as rigid bar constraints. We study the mechanical stability of proteins using FIRST (Floppy Inclusions and Rigid Substructure Topography) based on a recently developed combinatorial constraint counting algorithm (the 3D Pebble Game), which is a generalization of the 2D pebble game (D. J. Jacobs and M. F. Thorpe, ``Generic Rigidity: The Pebble Game'', Phys. Rev. Lett.) 75, 4051-4054 (1995) for the special class of bond-bending networks (D. J. Jacobs, "Generic Rigidity in Three Dimensional Bond-bending Networks", Preprint Aug (1997)). This approach is useful in identifying rigid motifs and flexible linkages in proteins, and thereby determines the essential degrees of freedom. We will show some preliminary results from the FIRST analysis on the myohemerythrin and lyozyme proteins.

A three-dimensional correlation method for registration of medical images in radiology

Energy Technology Data Exchange (ETDEWEB)

Georgiou, Michalakis; Sfakianakis, George N [Department of Radiology, University of Miami, Jackson Memorial Hospital, Miami, FL 33136 (United States); Nagel, Joachim H [Institute of Biomedical Engineering, University of Stuttgart, Stuttgart 70174 (Germany)

1999-12-31

The availability of methods to register multi-modality images in order to `fuse` them to correlate their information is increasingly becoming an important requirement for various diagnostic and therapeutic procedures. A variety of image registration methods have been developed but they remain limited to specific clinical applications. Assuming rigid body transformation, two images can be registered if their differences are calculated in terms of translation, rotation and scaling. This paper describes the development and testing of a new correlation based approach for three-dimensional image registration. First, the scaling factors introduced by the imaging devices are calculated and compensated for. Then, the two images become translation invariant by computing their three-dimensional Fourier magnitude spectra. Subsequently, spherical coordinate transformation is performed and then the three-dimensional rotation is computed using a novice approach referred to as {sup p}olar Shells{sup .} The method of polar shells maps the three angles of rotation into one rotation and two translations of a two-dimensional function and then proceeds to calculate them using appropriate transformations based on the Fourier invariance properties. A basic assumption in the method is that the three-dimensional rotation is constrained to one large and two relatively small angles. This assumption is generally satisfied in normal clinical settings. The new three-dimensional image registration method was tested with simulations using computer generated phantom data as well as actual clinical data. Performance analysis and accuracy evaluation of the method using computer simulations yielded errors in the sub-pixel range. (authors) 6 refs., 3 figs.

A three-dimensional correlation method for registration of medical images in radiology

International Nuclear Information System (INIS)

Georgiou, Michalakis; Sfakianakis, George N.; Nagel, Joachim H.

1998-01-01

The availability of methods to register multi-modality images in order to 'fuse' them to correlate their information is increasingly becoming an important requirement for various diagnostic and therapeutic procedures. A variety of image registration methods have been developed but they remain limited to specific clinical applications. Assuming rigid body transformation, two images can be registered if their differences are calculated in terms of translation, rotation and scaling. This paper describes the development and testing of a new correlation based approach for three-dimensional image registration. First, the scaling factors introduced by the imaging devices are calculated and compensated for. Then, the two images become translation invariant by computing their three-dimensional Fourier magnitude spectra. Subsequently, spherical coordinate transformation is performed and then the three-dimensional rotation is computed using a novice approach referred to as p olar Shells . The method of polar shells maps the three angles of rotation into one rotation and two translations of a two-dimensional function and then proceeds to calculate them using appropriate transformations based on the Fourier invariance properties. A basic assumption in the method is that the three-dimensional rotation is constrained to one large and two relatively small angles. This assumption is generally satisfied in normal clinical settings. The new three-dimensional image registration method was tested with simulations using computer generated phantom data as well as actual clinical data. Performance analysis and accuracy evaluation of the method using computer simulations yielded errors in the sub-pixel range. (authors)

Recent development of three-dimensional piping code SHAPS

International Nuclear Information System (INIS)

Wang, C.Y.; Zeuch, W.R.

1985-01-01

This paper describes the recent development of the three-dimensional, structural, and hydrodynamic analysis piping code SHAPS. Several new features have been incorporated into the program, including (1) an elbow hydrodynamic model for analyzing the effect of global motion on the pressure-wave propagation, (2) a component hydrodynamic model for treating fluid motion in the vicinity of rigid obstacles and baffle plates, (3) the addition of the implicit time integration scheme in the structural-dynamic analysis, (4) the option of an implicit-implicit fluid-structural linking scheme, and (5) provisions for two constitutive equations for materials under various loading conditions. Sample problems are given to illustrate these features. Their results are discussed in detail. 7 refs., 8 figs

Potential-based methodology for active sound control in three dimensional settings

OpenAIRE

Lim, H.; Utyuzhnikov, S V; Lam, Y.W.; Kelly, L.

2014-01-01

This paper extends a potential-based approach to active noise shielding with preservation of wanted sound in three-dimensional settings. The approach, which was described in a previous publication [Lim et al., J. Acoust. Soc. Am. 129(2), 717–725 (2011)], provides several significant advantages over conventional noise control methods. Most significantly, the methodology does not require any information including the characterization of sources, impedance boundary conditions and surrounding med...

Three-dimensional oblique water-entry problems at small deadrise angles

KAUST Repository

Moore, M. R.

2012-09-19

This paper extends Wagner theory for the ideal, incompressible normal impact of rigid bodies that are nearly parallel to the surface of a liquid half-space. The impactors considered are three-dimensional and have an oblique impact velocity. A formulation in terms of the displacement potential is used to reveal the relationship between the oblique and corresponding normal impact solutions. In the case of axisymmetric impactors, several geometries are considered in which singularities develop in the boundary of the effective wetted region. We present the corresponding pressure profiles and models for the splash sheets. © 2012 Cambridge University Press.

Three-dimensional oblique water-entry problems at small deadrise angles

KAUST Repository

Moore, M. R.; Howison, S. D.; Ockendon, J. R.; Oliver, J. M.

2012-01-01

This paper extends Wagner theory for the ideal, incompressible normal impact of rigid bodies that are nearly parallel to the surface of a liquid half-space. The impactors considered are three-dimensional and have an oblique impact velocity. A formulation in terms of the displacement potential is used to reveal the relationship between the oblique and corresponding normal impact solutions. In the case of axisymmetric impactors, several geometries are considered in which singularities develop in the boundary of the effective wetted region. We present the corresponding pressure profiles and models for the splash sheets. © 2012 Cambridge University Press.

Three-dimensional ICT reconstruction

International Nuclear Information System (INIS)

Zhang Aidong; Li Ju; Chen Fa; Sun Lingxia

2005-01-01

The three-dimensional ICT reconstruction method is the hot topic of recent ICT technology research. In the context, qualified visual three-dimensional ICT pictures are achieved through multi-piece two-dimensional images accumulation by, combining with thresholding method and linear interpolation. Different direction and different position images of the reconstructed pictures are got by rotation and interception respectively. The convenient and quick method is significantly instructive to more complicated three-dimensional reconstruction of ICT images. (authors)

Three-dimensional ICT reconstruction

International Nuclear Information System (INIS)

Zhang Aidong; Li Ju; Chen Fa; Sun Lingxia

2004-01-01

The three-dimensional ICT reconstruction method is the hot topic of recent ICT technology research. In the context qualified visual three-dimensional ICT pictures are achieved through multi-piece two-dimensional images accumulation by order, combining with thresholding method and linear interpolation. Different direction and different position images of the reconstructed pictures are got by rotation and interception respectively. The convenient and quick method is significantly instructive to more complicated three-dimensional reconstruction of ICT images. (authors)

Direct Linear System Identification Method for Multistory Three-dimensional Building Structure with General Eccentricity

OpenAIRE

Shintani, Kenichirou; Yoshitomi, Shinta; Takewaki, Izuru

2017-01-01

A method of physical parameter system identification (SI) is proposed here for three-dimensional (3D) building structures with in-plane rigid floors in which the stiffness and damping coefficients of each structural frame in the 3D building structure are identified from the measured floor horizontal accelerations. A batch processing least-squares estimation method for many discrete time domain measured data is proposed for the direct identification of the stiffness and damping coefficients of...

Three-dimensional analysis of craniofacial bones using three-dimensional computer tomography

Energy Technology Data Exchange (ETDEWEB)

Ono, Ichiro; Ohura, Takehiko; Kimura, Chu (Hokkaido Univ., Sapporo (Japan). School of Medicine) (and others)

1989-08-01

Three-dimensional computer tomography (3DCT) was performed in patients with various diseases to visualize stereoscopically the deformity of the craniofacial bones. The data obtained were analyzed by the 3DCT analyzing system. A new coordinate system was established using the median sagittal plane of the face (a plane passing through sella, nasion and basion) on the three-dimensional image. Three-dimensional profilograms were prepared for detailed analysis of the deformation of craniofacial bones for cleft lip and palate, mandibular prognathia and hemifacial microsomia. For patients, asymmetry in the frontal view and twist-formed complicated deformities were observed, as well as deformity of profiles in the anteroposterior and up-and-down directions. A newly developed technique allows three-dimensional visualization of changes in craniofacial deformity. It would aid in determining surgical strategy, including crani-facial surgery and maxillo-facial surgery, and in evaluating surgical outcome. (N.K.).

Three-dimensional analysis of craniofacial bones using three-dimensional computer tomography

International Nuclear Information System (INIS)

Ono, Ichiro; Ohura, Takehiko; Kimura, Chu

1989-01-01

Three-dimensional computer tomography (3DCT) was performed in patients with various diseases to visualize stereoscopically the deformity of the craniofacial bones. The data obtained were analyzed by the 3DCT analyzing system. A new coordinate system was established using the median sagittal plane of the face (a plane passing through sella, nasion and basion) on the three-dimensional image. Three-dimensional profilograms were prepared for detailed analysis of the deformation of craniofacial bones for cleft lip and palate, mandibular prognathia and hemifacial microsomia. For patients, asymmetry in the frontal view and twist-formed complicated deformities were observed, as well as deformity of profiles in the anteroposterior and up-and-down directions. A newly developed technique allows three-dimensional visualization of changes in craniofacial deformity. It would aid in determining surgical strategy, including crani-facial surgery and maxillo-facial surgery, and in evaluating surgical outcome. (N.K.)

Rigidity Sensing Explained by Active Matter Theory

OpenAIRE

Marcq, Philippe; Yoshinaga, Natsuhiko; Prost, Jacques

2011-01-01

The magnitude of traction forces exerted by living animal cells on their environment is a monotonically increasing and approximately sigmoidal function of the stiffness of the external medium. We rationalize this observation using active matter theory, and propose that adaptation to substrate rigidity results from an interplay between passive elasticity and active contractility.

Three-dimensional assessment of brain tissue morphology

Science.gov (United States)

Müller, Bert; Germann, Marco; Jeanmonod, Daniel; Morel, Anne

2006-08-01

The microstructure of brain tissues becomes visible using different types of optical microscopy after the tissue sectioning. This preparation procedure introduces stress and strain in the anisotropic and inhomogeneous soft tissue slices, which are several 10 μm thick. Consequently, the three-dimensional dataset, generated out of the two-dimensional images with lateral submicrometer resolution, needs algorithms to correct the deformations, which can be significant for mellow tissue such as brain segments. The spatial resolution perpendicular to the slices is much worse with respect to the lateral sub-micrometer resolution. Therefore, we propose as complementary method the synchrotron-radiation-based micro computed tomography (SRμCT), which avoids any kind of preparation artifacts due to sectioning and histological processing and yields true micrometer resolution in the three orthogonal directions. The visualization of soft matter by the use of SRμCT, however, is often based on elaborate staining protocols, since the tissue exhibits (almost) the same x-ray absorption as the surrounding medium. Therefore, it is unexpected that human tissue from the pons and the medulla oblongata in phosphate buffer show several features such as the blood vessels and the inferior olivary nucleus without staining. The value of these tomograms lies especially in the precise non-rigid registration of the different sets of histological slices. Applications of this method to larger pieces of brain tissue, such as the human thalamus are planned in the context of stereotactic functional neurosurgery.

Three dimensional strained semiconductors

Science.gov (United States)

Voss, Lars; Conway, Adam; Nikolic, Rebecca J.; Leao, Cedric Rocha; Shao, Qinghui

2016-11-08

In one embodiment, an apparatus includes a three dimensional structure comprising a semiconductor material, and at least one thin film in contact with at least one exterior surface of the three dimensional structure for inducing a strain in the structure, the thin film being characterized as providing at least one of: an induced strain of at least 0.05%, and an induced strain in at least 5% of a volume of the three dimensional structure. In another embodiment, a method includes forming a three dimensional structure comprising a semiconductor material, and depositing at least one thin film on at least one surface of the three dimensional structure for inducing a strain in the structure, the thin film being characterized as providing at least one of: an induced strain of at least 0.05%, and an induced strain in at least 5% of a volume of the structure.

Three dimensional investigation on the oceanic active fault. A demonstration survey

Energy Technology Data Exchange (ETDEWEB)

Nakao, Seizo; Kishimoto, Kiyoyuki; Okamoto, Yukinobu; Ikehara, Ken; Kuramoto, Shinichi; Sato, Mikio; Arai, Kosaku [Geological Survey of Japan, Tsukuba, Ibaraki (Japan)

2000-02-01

In order to upgrade activity and likelihood ratio on active potential evaluation of the water active fault with possibility of severe effect on nuclear facilities, by generally applying the conventional procedures to some areas and carrying out a demonstration survey, a qualitative upgrading on survey to be conducted by the executives was planned. In 1998 fiscal year, among the water active faults classified to the trench and the inland types, three dimensional survey on the inland type water active fault. The survey was carried out at the most southern part of aftershock area in the 1983 Nihonkai-Chubu earthquake, which is understood to be a place changing shallow geological structure (propagation of fault) from an old report using the sonic survey. As a result, a geological structure thought to be an active fault at a foot of two ridge topographies was found. Each fault was thought to be a reverse fault tilt to its opposite direction and an active fault cutting to its sea bottom. (G.K.)

Three dimensional investigation on the oceanic active fault. A demonstration survey

International Nuclear Information System (INIS)

Nakao, Seizo; Kishimoto, Kiyoyuki; Okamoto, Yukinobu; Ikehara, Ken; Kuramoto, Shinichi; Sato, Mikio; Arai, Kosaku

2000-01-01

In order to upgrade activity and likelihood ratio on active potential evaluation of the water active fault with possibility of severe effect on nuclear facilities, by generally applying the conventional procedures to some areas and carrying out a demonstration survey, a qualitative upgrading on survey to be conducted by the executives was planned. In 1998 fiscal year, among the water active faults classified to the trench and the inland types, three dimensional survey on the inland type water active fault. The survey was carried out at the most southern part of aftershock area in the 1983 Nihonkai-Chubu earthquake, which is understood to be a place changing shallow geological structure (propagation of fault) from an old report using the sonic survey. As a result, a geological structure thought to be an active fault at a foot of two ridge topographies was found. Each fault was thought to be a reverse fault tilt to its opposite direction and an active fault cutting to its sea bottom. (G.K.)

Conformational Rigidity and Protein Dynamics at Distinct Timescales Regulate PTP1B Activity and Allostery.

Science.gov (United States)

Choy, Meng S; Li, Yang; Machado, Luciana E S F; Kunze, Micha B A; Connors, Christopher R; Wei, Xingyu; Lindorff-Larsen, Kresten; Page, Rebecca; Peti, Wolfgang

2017-02-16

Protein function originates from a cooperation of structural rigidity, dynamics at different timescales, and allostery. However, how these three pillars of protein function are integrated is still only poorly understood. Here we show how these pillars are connected in Protein Tyrosine Phosphatase 1B (PTP1B), a drug target for diabetes and cancer that catalyzes the dephosphorylation of numerous substrates in essential signaling pathways. By combining new experimental and computational data on WT-PTP1B and ≥10 PTP1B variants in multiple states, we discovered a fundamental and evolutionarily conserved CH/π switch that is critical for positioning the catalytically important WPD loop. Furthermore, our data show that PTP1B uses conformational and dynamic allostery to regulate its activity. This shows that both conformational rigidity and dynamics are essential for controlling protein activity. This connection between rigidity and dynamics at different timescales is likely a hallmark of all enzyme function. Copyright © 2017 Elsevier Inc. All rights reserved.

The use of the co-ordinate measuring machine for the study of three-dimensional biomechanics of the knee.

Science.gov (United States)

Veselko, M; Jenko, M; Lipuscek, I

1998-07-01

Original methodology for the study of three-dimensional biomechanics of the knee is presented in the paper. Defining the geometry of the rigid body in the body-fixed reference frame and the orientation of the body-fixed reference frame in the global co-ordinate system are the theoretic basis. The data in the form of co-ordinates of the Cartesian frame are gathered by the co-ordinate measuring machine and analysed by specially computer program. The theory and a practical example of the study of the three-dimensional biomechanics of the knee are presented. Various possibilities of the use of the methodology are discussed.

Flat tori in three-dimensional space and convex integration.

Science.gov (United States)

Borrelli, Vincent; Jabrane, Saïd; Lazarus, Francis; Thibert, Boris

2012-05-08

It is well-known that the curvature tensor is an isometric invariant of C(2) Riemannian manifolds. This invariant is at the origin of the rigidity observed in Riemannian geometry. In the mid 1950s, Nash amazed the world mathematical community by showing that this rigidity breaks down in regularity C(1). This unexpected flexibility has many paradoxical consequences, one of them is the existence of C(1) isometric embeddings of flat tori into Euclidean three-dimensional space. In the 1970s and 1980s, M. Gromov, revisiting Nash's results introduced convex integration theory offering a general framework to solve this type of geometric problems. In this research, we convert convex integration theory into an algorithm that produces isometric maps of flat tori. We provide an implementation of a convex integration process leading to images of an embedding of a flat torus. The resulting surface reveals a C(1) fractal structure: Although the tangent plane is defined everywhere, the normal vector exhibits a fractal behavior. Isometric embeddings of flat tori may thus appear as a geometric occurrence of a structure that is simultaneously C(1) and fractal. Beyond these results, our implementation demonstrates that convex integration, a theory still confined to specialists, can produce computationally tractable solutions of partial differential relations.

Three-dimensional, three-component wall-PIV

Science.gov (United States)

Berthe, André; Kondermann, Daniel; Christensen, Carolyn; Goubergrits, Leonid; Garbe, Christoph; Affeld, Klaus; Kertzscher, Ulrich

2010-06-01

This paper describes a new time-resolved three-dimensional, three-component (3D-3C) measurement technique called wall-PIV. It was developed to assess near wall flow fields and shear rates near non-planar surfaces. The method is based on light absorption according to Beer-Lambert’s law. The fluid containing a molecular dye and seeded with buoyant particles is illuminated by a monochromatic, diffuse light. Due to the dye, the depth of view is limited to the near wall layer. The three-dimensional particle positions can be reconstructed by the intensities of the particle’s projection on an image sensor. The flow estimation is performed by a new algorithm, based on learned particle trajectories. Possible sources of measurement errors related to the wall-PIV technique are analyzed. The accuracy analysis was based on single particle experiments and a three-dimensional artificial data set simulating a rotating sphere.

An efficient semi-implicit method for three-dimensional non-hydrostatic flows in compliant arterial vessels.

Science.gov (United States)

Fambri, Francesco; Dumbser, Michael; Casulli, Vincenzo

2014-11-01

Blood flow in arterial systems can be described by the three-dimensional Navier-Stokes equations within a time-dependent spatial domain that accounts for the elasticity of the arterial walls. In this article, blood is treated as an incompressible Newtonian fluid that flows through compliant vessels of general cross section. A three-dimensional semi-implicit finite difference and finite volume model is derived so that numerical stability is obtained at a low computational cost on a staggered grid. The key idea of the method consists in a splitting of the pressure into a hydrostatic and a non-hydrostatic part, where first a small quasi-one-dimensional nonlinear system is solved for the hydrostatic pressure and only in a second step the fully three-dimensional non-hydrostatic pressure is computed from a three-dimensional nonlinear system as a correction to the hydrostatic one. The resulting algorithm is robust, efficient, locally and globally mass conservative, and applies to hydrostatic and non-hydrostatic flows in one, two and three space dimensions. These features are illustrated on nontrivial test cases for flows in tubes with circular or elliptical cross section where the exact analytical solution is known. Test cases of steady and pulsatile flows in uniformly curved rigid and elastic tubes are presented. Wherever possible, axial velocity development and secondary flows are shown and compared with previously published results. Copyright © 2014 John Wiley & Sons, Ltd.

Semi-Active Control of Three-Dimensional Vibrations of an Inclined Sag Cable with Magnetorheological Dampers

DEFF Research Database (Denmark)

Zhou, Q.; Nielsen, Søren R.K.; Qu, W. L.

2006-01-01

Three-dimensional semi-active vibration control of an inclined sag cable with discrete magnetorheological (MR) dampers is investigated in this paper using the finite difference method (FDM). A modified Dahl model is used to describe the dynamic property of MR damper. The nonlinear equations...

Three-dimensional effects in fracture mechanics

International Nuclear Information System (INIS)

Benitez, F.G.

1991-01-01

An overall view of the pioneering theories and works, which enlighten the three-dimensional nature of fracture mechanics during the last years is given. the main aim is not an exhaustive reviewing but the displaying of the last developments on this scientific field in a natural way. This work attempts to envisage the limits of disregarding the three-dimensional behaviour in theories, analyses and experiments. Moreover, it tries to draw attention on the scant fervour, although increasing, this three-dimensional nature of fracture has among the scientific community. Finally, a constructive discussion is presented on the use of two-dimensional solutions in the analysis of geometries which bear a three-dimensional configuration. the static two-dimensional solutions and its applications fields are reviewed. also, the static three-dimensional solutions, wherein a comparative analysis with elastoplastic and elastostatic solutions are presented. to end up, the dynamic three-dimensional solutions are compared to the asymptotic two-dimensional ones under the practical applications point of view. (author)

Electron tomography, three-dimensional Fourier analysis and colour prediction of a three-dimensional amorphous biophotonic nanostructure

Science.gov (United States)

Shawkey, Matthew D.; Saranathan, Vinodkumar; Pálsdóttir, Hildur; Crum, John; Ellisman, Mark H.; Auer, Manfred; Prum, Richard O.

2009-01-01

Organismal colour can be created by selective absorption of light by pigments or light scattering by photonic nanostructures. Photonic nanostructures may vary in refractive index over one, two or three dimensions and may be periodic over large spatial scales or amorphous with short-range order. Theoretical optical analysis of three-dimensional amorphous nanostructures has been challenging because these structures are difficult to describe accurately from conventional two-dimensional electron microscopy alone. Intermediate voltage electron microscopy (IVEM) with tomographic reconstruction adds three-dimensional data by using a high-power electron beam to penetrate and image sections of material sufficiently thick to contain a significant portion of the structure. Here, we use IVEM tomography to characterize a non-iridescent, three-dimensional biophotonic nanostructure: the spongy medullary layer from eastern bluebird Sialia sialis feather barbs. Tomography and three-dimensional Fourier analysis reveal that it is an amorphous, interconnected bicontinuous matrix that is appropriately ordered at local spatial scales in all three dimensions to coherently scatter light. The predicted reflectance spectra from the three-dimensional Fourier analysis are more precise than those predicted by previous two-dimensional Fourier analysis of transmission electron microscopy sections. These results highlight the usefulness, and obstacles, of tomography in the description and analysis of three-dimensional photonic structures. PMID:19158016

Three-dimensional biomedical imaging

International Nuclear Information System (INIS)

Robb, R.A.

1985-01-01

Scientists in biomedical imaging provide researchers, physicians, and academicians with an understanding of the fundamental theories and practical applications of three-dimensional biomedical imaging methodologies. Succinct descriptions of each imaging modality are supported by numerous diagrams and illustrations which clarify important concepts and demonstrate system performance in a variety of applications. Comparison of the different functional attributes, relative advantages and limitations, complementary capabilities, and future directions of three-dimensional biomedical imaging modalities are given. Volume 1: Introductions to Three-Dimensional Biomedical Imaging Photoelectronic-Digital Imaging for Diagnostic Radiology. X-Ray Computed Tomography - Basic Principles. X-Ray Computed Tomography - Implementation and Applications. X-Ray Computed Tomography: Advanced Systems and Applications in Biomedical Research and Diagnosis. Volume II: Single Photon Emission Computed Tomography. Position Emission Tomography (PET). Computerized Ultrasound Tomography. Fundamentals of NMR Imaging. Display of Multi-Dimensional Biomedical Image Information. Summary and Prognostications

Second-Order Inelastic Dynamic Analysis of 3D Semi-Rigid Steel Frames Under Earthquake Loads with Three Components

International Nuclear Information System (INIS)

Ozakgul, Kadir

2008-01-01

In this study, it has been presented an algorithm for second-order elastoplastic dynamic time-history analysis of three dimensional frames that have steel members with semirigid joints. The proposed analysis accounts for material, geometric and connection nonlinearities. Material nonlinearity have been modeled by the Ramberg-Osgood relation. While the geometric nonlinearity caused by axial force has been described by the use of the geometric stiffness matrix, the nonlinearity caused by the interaction between the axial force and bending moment has been also described by the use of the stability functions. The independent hardening model has been used to describe the nonlinear behaviour of semi-rigid connections. Dynamic equation of motion has been solved by Newmark's constant acceleration method in time history domain

A Robust and Accurate Two-Step Auto-Labeling Conditional Iterative Closest Points (TACICP Algorithm for Three-Dimensional Multi-Modal Carotid Image Registration.

Directory of Open Access Journals (Sweden)

Hengkai Guo

Full Text Available Atherosclerosis is among the leading causes of death and disability. Combining information from multi-modal vascular images is an effective and efficient way to diagnose and monitor atherosclerosis, in which image registration is a key technique. In this paper a feature-based registration algorithm, Two-step Auto-labeling Conditional Iterative Closed Points (TACICP algorithm, is proposed to align three-dimensional carotid image datasets from ultrasound (US and magnetic resonance (MR. Based on 2D segmented contours, a coarse-to-fine strategy is employed with two steps: rigid initialization step and non-rigid refinement step. Conditional Iterative Closest Points (CICP algorithm is given in rigid initialization step to obtain the robust rigid transformation and label configurations. Then the labels and CICP algorithm with non-rigid thin-plate-spline (TPS transformation model is introduced to solve non-rigid carotid deformation between different body positions. The results demonstrate that proposed TACICP algorithm has achieved an average registration error of less than 0.2mm with no failure case, which is superior to the state-of-the-art feature-based methods.

Type number and rigidity of fibred surfaces

International Nuclear Information System (INIS)

Markov, P E

2001-01-01

Infinitesimal l-th order bendings, 1≤l≤∞, of higher-dimensional surfaces are considered in higher-dimensional flat spaces (for l=∞ an infinitesimal bending is assumed to be an analytic bending). In terms of the Allendoerfer type number, criteria are established for the (r,l)-rigidity (in the terminology of Sabitov) of such surfaces. In particular, an (r,l)-infinitesimal analogue is proved of the classical theorem of Allendoerfer on the unbendability of surfaces with type number ≥3 and the class of (r,l)-rigid fibred surfaces is distinguished

Left ventricular rigid body rotation in a diffuse large B-cell lymphoma patient with cardiac involvement: A case from the three-dimensional speckle-tracking echocardiographic MAGYAR-Path Study.

Science.gov (United States)

Földeák, Dóra; Kalapos, Anita; Domsik, Péter; Sinkó, Mária; Szeleczki, Nóra; Bagdi, Enikő; Krenács, László; Forster, Tamás; Borbényi, Zita; Nemes, Attila

2017-02-01

Secondary myocardial involvement by diffuse large B-cell lymphoma is a rare occurrence. Left ventricular (LV) twist is considered an essential part of LV function. In normal circumstances LV twist results from the movement of two orthogonally oriented muscular bands of a helical myocardial structure with consequent clockwise rotation of the base and counterclockwise rotation of the apex. Three-dimensional (3D) speckle-tracking echocardiography (3DSTE) has been found to be feasible for non-invasive 3D quantification of LV wall motion and rotational mechanics. The present report aimed to assess LV twisting motion in a patient with diffuse large B-cell lymphoma with positron emission tomography/computer tomography-proven cardiac involvement by 3DSTE. During 3DSTE, reduction in some segmental radial, longitudinal, circumferential, area and 3D LV strains were found. Apical and basal LV rotations were found to be in the same counterclockwise direction, confirming near absence of LV twist - so-called rigid body rotation. Copyright © 2016 Sociedade Portuguesa de Cardiologia. Publicado por Elsevier España, S.L.U. All rights reserved.

Three dimensional canonical transformations

International Nuclear Information System (INIS)

Tegmen, A.

2010-01-01

A generic construction of canonical transformations is given in three-dimensional phase spaces on which Nambu bracket is imposed. First, the canonical transformations are defined as based on cannonade transformations. Second, it is shown that determination of the generating functions and the transformation itself for given generating function is possible by solving correspondent Pfaffian differential equations. Generating functions of type are introduced and all of them are listed. Infinitesimal canonical transformations are also discussed as the complementary subject. Finally, it is shown that decomposition of canonical transformations is also possible in three-dimensional phase spaces as in the usual two-dimensional ones.

Exotic distributions of rigid unit modes in the reciprocal spaces of framework aluminosilicates

International Nuclear Information System (INIS)

Dove, Martin T; Pryde, Alexandra K A; Heine, Volker; Hammonds, Kenton D

2007-01-01

Until recently it was assumed that rigid unit modes, defined as the zero-frequency solutions to the dynamical equations for an infinite framework of rigid corner-linked tetrahedra, were confined to a small set of normal modes with wavevectors on lines or planes of special symmetry in reciprocal space. Using a search method that explores the full three-dimensional reciprocal space, we have located rigid unit modes with wavevectors on exotic curved surfaces in reciprocal space for a range of silicate minerals. This has led to the realization that the crystal structures of these minerals contain rather more topological floppiness than had previously been realized. The origin of the exotic RUM surfaces remains to be understood

A three-dimensional graphene-TiO{sub 2} nanotube nanocomposite with exceptional photocatalytic activity for dye degradation

Energy Technology Data Exchange (ETDEWEB)

Zhao, Fenghuan [Institute of Material Science and Engineering, Ocean University of China, 266000 Qingdao (China); Dong, Bohua, E-mail: dongbohua@ouc.edu.cn [Institute of Material Science and Engineering, Ocean University of China, 266000 Qingdao (China); Gao, Rongjie; Su, Ge; Liu, Wei [Institute of Material Science and Engineering, Ocean University of China, 266000 Qingdao (China); Shi, Liang [College of Chemistry and Chemical Engineering, Ocean University of China, 266000 Qingdao (China); Xia, Chenghui [Debye Institute, Utrecht University, Princetonplein 1, 3584 CC Utrecht (Netherlands); Cao, Lixin, E-mail: caolixin@ouc.edu.cn [Institute of Material Science and Engineering, Ocean University of China, 266000 Qingdao (China)

2015-10-01

Highlights: • A new kind of three-dimensional graphene/TiO{sub 2} nanotube composites were fabricated by facile hydrothermal method. • The graphene with optimized amount has a great influence on the photocatalytic activity of TiO{sub 2}. • The special and well-structured composites nanomaterials have outstanding photocatalytic activity. - Abstract: Three dimensional nanocomposites made up of TiO{sub 2} nanotubes (TNTs) and conducting reduced graphene oxide nanosheets (RGO) were fabricated successfully via hydrothermal method. These graphene/TNTs nanocomposites (GTNCs) with unique nanostructure not only provided sufficient active sites but supplied electron-transport path, Which gave big rise to their photocatalytic activity. In addition, the graphene amount and calcination temperature were intensively optimized. A series of products were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and UV–vis absorption spectroscopy. The photocatalytic activity of as-prepared GTNCs was investigated through the degradation of methyl orange (MO) under UV-light irradiation. The results show that these GTNCs are well-structured with outstanding photocatalytic activity which is much better than that of traditional TiO{sub 2} nanotubes.

Three-dimensional microbubble streaming flows

Science.gov (United States)

Rallabandi, Bhargav; Marin, Alvaro; Rossi, Massimiliano; Kaehler, Christian; Hilgenfeldt, Sascha

2014-11-01

Streaming due to acoustically excited bubbles has been used successfully for applications such as size-sorting, trapping and focusing of particles, as well as fluid mixing. Many of these applications involve the precise control of particle trajectories, typically achieved using cylindrical bubbles, which establish planar flows. Using astigmatic particle tracking velocimetry (APTV), we show that, while this two-dimensional picture is a useful description of the flow over short times, a systematic three-dimensional flow structure is evident over long time scales. We demonstrate that this long-time three-dimensional fluid motion can be understood through asymptotic theory, superimposing secondary axial flows (induced by boundary conditions at the device walls) onto the two-dimensional description. This leads to a general framework that describes three-dimensional flows in confined microstreaming systems, guiding the design of applications that profit from minimizing or maximizing these effects.

On Classical Dynamics of Affinely-Rigid Bodies Subject to the Kirchhoff-Love Constraints

Directory of Open Access Journals (Sweden)

Vasyl Kovalchuk

2010-04-01

Full Text Available In this article we consider the affinely-rigid body moving in the three-dimensional physical space and subject to the Kirchhoff-Love constraints, i.e., while it deforms homogeneously in the two-dimensional central plane of the body it simultaneously performs one-dimensional oscillations orthogonal to this central plane. For the polar decomposition we obtain the stationary ellipsoids as special solutions of the general, strongly nonlinear equations of motion. It is also shown that these solutions are conceptually different from those obtained earlier for the two-polar (singular value decomposition.

Three-dimensional features on oscillating microbubbles streaming flows

Science.gov (United States)

Rossi, Massimiliano; Marin, Alvaro G.; Wang, Cheng; Hilgenfeldt, Sascha; Kähler, Christian J.

2013-11-01

Ultrasound-driven oscillating micro-bubbles have been used as active actuators in microfluidic devices to perform manifold tasks such as mixing, sorting and manipulation of microparticles. A common configuration consists in side-bubbles, created by trapping air pockets in blind channels perpendicular to the main channel direction. This configuration results in bubbles with a semi-cylindrical shape that creates a streaming flow generally considered quasi two-dimensional. However, recent experiments performed with three-dimensional velocimetry methods have shown how microparticles can present significant three-dimensional trajectories, especially in regions close to the bubble interface. Several reasons will be discussed such as boundary effects of the bottom/top wall, deformation of the bubble interface leading to more complex vibrational modes, or bubble-particle interactions. In the present investigation, precise measurements of particle trajectories close to the bubble interface will be performed by means of 3D Astigmatic Particle Tracking Velocimetry. The results will allow us to characterize quantitatively the three-dimensional features of the streaming flow and to estimate its implications in practical applications as particle trapping, sorting or mixing.

Three-dimensional magnetospheric equilibrium with isotropic pressure

International Nuclear Information System (INIS)

Cheng, C.Z.

1995-05-01

In the absence of the toroidal flux, two coupled quasi two-dimensional elliptic equilibrium equations have been derived to describe self-consistent three-dimensional static magnetospheric equilibria with isotropic pressure in an optimal (Ψ,α,χ) flux coordinate system, where Ψ is the magnetic flux function, χ is a generalized poloidal angle, α is the toroidal angle, α = φ - δ(Ψ,φ,χ) is the toroidal angle, δ(Ψ,φ,χ) is periodic in φ, and the magnetic field is represented as rvec B = ∇Ψ x ∇α. A three-dimensional magnetospheric equilibrium code, the MAG-3D code, has been developed by employing an iterative metric method. The main difference between the three-dimensional and the two-dimensional axisymmetric solutions is that the field-aligned current and the toroidal magnetic field are finite for the three-dimensional case, but vanish for the two-dimensional axisymmetric case. With the same boundary flux surface shape, the two-dimensional axisymmetric results are similar to the three-dimensional magnetosphere at each local time cross section

Three dimensional visualization of medical images

International Nuclear Information System (INIS)

Suto, Yasuzo

1992-01-01

Three dimensional visualization is a stereoscopic technique that allows the diagnosis and treatment of complicated anatomy site of the bone and organ. In this article, the current status and technical application of three dimensional visualization are introduced with special reference to X-ray CT and MRI. The surface display technique is the most common for three dimensional visualization, consisting of geometric model, voxel element, and stereographic composition techniques. Recent attention has been paid to display method of the content of the subject called as volume rendering, whereby information on the living body is provided accurately. The application of three dimensional visualization is described in terms of diagnostic imaging and surgical simulation. (N.K.)

(Weakly) three-dimensional caseology

International Nuclear Information System (INIS)

Pomraning, G.C.

1996-01-01

The singular eigenfunction technique of Case for solving one-dimensional planar symmetry linear transport problems is extended to a restricted class of three-dimensional problems. This class involves planar geometry, but with forcing terms (either boundary conditions or internal sources) which are weakly dependent upon the transverse spatial variables. Our analysis involves a singular perturbation about the classic planar analysis, and leads to the usual Case discrete and continuum modes, but modulated by weakly dependent three-dimensional spatial functions. These functions satisfy parabolic differential equations, with a different diffusion coefficient for each mode. Representative one-speed time-independent transport problems are solved in terms of these generalised Case eigenfunctions. Our treatment is very heuristic, but may provide an impetus for more rigorous analysis. (author)

A concise introduction to mechanics of rigid bodies multidisciplinary engineering

CERN Document Server

Huang, L

2017-01-01

This updated second edition broadens the explanation of rotational kinematics and dynamics — the most important aspect of rigid body motion in three-dimensional space and a topic of much greater complexity than linear motion. It expands treatment of vector and matrix, and includes quaternion operations to describe and analyze rigid body motion which are found in robot control, trajectory planning, 3D vision system calibration, and hand-eye coordination of robots in assembly work, etc. It features updated treatments of concepts in all chapters and case studies. The textbook retains its comprehensiveness in coverage and compactness in size, which make it easily accessible to the readers from multidisciplinary areas who want to grasp the key concepts of rigid body mechanics which are usually scattered in multiple volumes of traditional textbooks. Theoretical concepts are explained through examples taken from across engineering disciplines and links to applications and more advanced courses (e.g. industrial rob...

Normal Reflection Characteristics of One-Dimensional Unsteady Flow Shock Waves on Rigid Walls from Pulse Discharge in Water

Directory of Open Access Journals (Sweden)

Dong Yan

2017-01-01

Full Text Available Strong shock waves can be generated by pulse discharge in water, and the characteristics due to the shock wave normal reflection from rigid walls have important significance to many fields, such as industrial production and defense construction. This paper investigates the effects of hydrostatic pressures and perturbation of wave source (i.e., charging voltage on normal reflection of one-dimensional unsteady flow shock waves. Basic properties of the incidence and reflection waves were analyzed theoretically and experimentally to identify the reflection mechanisms and hence the influencing factors and characteristics. The results indicated that increased perturbation (i.e., charging voltage leads to increased peak pressure and velocity of the reflected shock wave, whereas increased hydrostatic pressure obviously inhibited superposition of the reflection waves close to the rigid wall. The perturbation of wave source influence on the reflected wave was much lower than that on the incident wave, while the hydrostatic pressure obviously affected both incident and reflection waves. The reflection wave from the rigid wall in water exhibited the characteristics of a weak shock wave, and with increased hydrostatic pressure, these weak shock wave characteristics became more obvious.

Three-dimensional friction measurement during hip simulation.

Directory of Open Access Journals (Sweden)

Robert Sonntag

Full Text Available Wear of total hip replacements has been the focus of many studies. However, frictional effects, such as high loading on intramodular connections or the interface to the bone, as well as friction associated squeaking have recently increased interest about the amount of friction that is generated during daily activities. The aim of this study was thus to establish and validate a three-dimensional friction setup under standardized conditions.A standard hip simulator was modified to allow for high precision measurements of small frictional effects in the hip during three-dimensional hip articulation. The setup was verified by an ideal hydrostatic bearing and validated with a static-load physical pendulum and an extension-flexion rotation with a dynamic load profile. Additionally, a pendulum model was proposed for screening measurement of frictional effects based on the damping behavior of the angular oscillation without the need for any force/moment transducer. Finally, three-dimensional friction measurements have been realized for ceramic-on-polyethylene bearings of three different sizes (28, 36 and 40 mm.A precision of less than 0.2 Nm during three-dimensional friction measurements was reported, while increased frictional torque (resultant as well as taper torque was measured for larger head diameters. These effects have been confirmed by simple pendulum tests and the theoretical model. A comparison with current literature about friction measurements is presented.This investigation of friction is able to provide more information about a field that has been dominated by the reduction of wear. It should be considered in future pre-clinical testing protocols given by international organizations of standardization.

Study on three dimensional seismic isolation system

International Nuclear Information System (INIS)

Morishita, Masaki; Kitamura, Seiji

2003-01-01

Japan Nuclear Cycle Development Institute (JNC) and Japan Atomic Power Company (JAPC) launched joint research programs on structural design and three-dimensional seismic isolation technologies, as part of the supporting R and D activities for the feasibility studies on commercialized fast breeder reactor cycle systems. A research project by JAPC under the auspices of the Ministry of Economy, Trade, and Industry (METI) with technical support by JNC is included in this joint study. This report contains the results of the research on the three-dimensional seismic isolation technologies, and the results of this year's study are summarized in the following five aspects. (1) Study on Earthquake Condition for Developing 3-dimensional Base Isolation System. The case study S2 is one of the maximum ground motions, of which the records were investigated up to this time. But a few observed near the fault exceed the case study S2 in the long period domain, depending on the fault length and conditions. Generally it is appropriate that the response spectra ratio (vertical/horizontal) is 0.6. (2) Performance Requirement for 3-dimensional Base Isolation System and Devices. Although the integrity map of main equipment/piping dominate the design criteria for the 3-dimensional base isolation system, the combined integrity map is the same as those of FY 2000, which are under fv=1Hz and over hv=20%. (3) Developing Targets and Schedule for 3-dimensional Isolation Technology. The target items for 3-dimensional base isolation system were rearranged into a table, and developing items to be examined concerning the device were also adjusted. A development plan until FY 2009 was made from the viewpoint of realization and establishment of a design guideline on 3-dimensional base isolation system. (4) Study on 3-dimensional Entire Building Base Isolation System. Three ideas among six ideas that had been proposed in FY2001, i.e., '3-dimensional base isolation system incorporating hydraulic

Magnetohydrodynamic study of three-dimensional instability of the spontaneous fast magnetic reconnection

International Nuclear Information System (INIS)

Shimizu, T.; Kondoh, K.; Ugai, M.; Shibata, K.

2009-01-01

Three-dimensional instability of the spontaneous fast magnetic reconnection is studied with magnetohydrodynamic (MHD) simulation, where the two-dimensional model of the spontaneous fast magnetic reconnection is destabilized in three dimension. Generally, in two-dimensional magnetic reconnection models, every plasma condition is assumed to be uniform in the sheet current direction. In such two-dimensional MHD simulations, the current sheet destabilized by the initial resistive disturbance can be developed to fast magnetic reconnection by a current driven anomalous resistivity. In this paper, the initial resistive disturbance includes a small amount of fluctuations in the sheet current direction, i.e., along the magnetic neutral line. The other conditions are the same as that of previous two-dimensional MHD studies for fast magnetic reconnection. Accordingly, we may expect that approximately two-dimensional fast magnetic reconnection occurs in the MHD simulation. In fact, the fast magnetic reconnection activated on the first stage of the simulation is two dimensional. However, on the subsequent stages, it spontaneously becomes three dimensional and is strongly localized in the sheet current direction. The resulting three-dimensional fast magnetic reconnection intermittently ejects three-dimensional magnetic loops. Such intermittent ejections of the three-dimensional loops are similar to the intermittent downflows observed in the solar flares. The ejection of the three-dimensional loops seems to be random but, numerically and theoretically, it is shown that the aspect ratio of the ejected loops is limited under a criterion.

Two-dimensional lift-up problem for a rigid porous bed

Energy Technology Data Exchange (ETDEWEB)

Chang, Y.; Huang, L. H.; Yang, F. P. Y. [Department of Civil Engineering, National Taiwan University, Taipei, Taiwan (China)

2015-05-15

The present study analytically reinvestigates the two-dimensional lift-up problem for a rigid porous bed that was studied by Mei, Yeung, and Liu [“Lifting of a large object from a porous seabed,” J. Fluid Mech. 152, 203 (1985)]. Mei, Yeung, and Liu proposed a model that treats the bed as a rigid porous medium and performed relevant experiments. In their model, they assumed the gap flow comes from the periphery of the gap, and there is a shear layer in the porous medium; the flow in the gap is described by adhesion approximation [D. J. Acheson, Elementary Fluid Dynamics (Clarendon, Oxford, 1990), pp. 243-245.] and the pore flow by Darcy’s law, and the slip-flow condition proposed by Beavers and Joseph [“Boundary conditions at a naturally permeable wall,” J. Fluid Mech. 30, 197 (1967)] is applied to the bed interface. In this problem, however, the gap flow initially mainly comes from the porous bed, and the shear layer may not exist. Although later the shear effect becomes important, the empirical slip-flow condition might not physically respond to the shear effect, and the existence of the vertical velocity affects the situation so greatly that the slip-flow condition might not be appropriate. In contrast, the present study proposes a more general model for the problem, applying Stokes flow to the gap, the Brinkman equation to the porous medium, and Song and Huang’s [“Laminar poroelastic media flow,” J. Eng. Mech. 126, 358 (2000)] complete interfacial conditions to the bed interface. The exact solution to the problem is found and fits Mei’s experiments well. The breakout phenomenon is examined for different soil beds, mechanics that cannot be illustrated by Mei’s model are revealed, and the theoretical breakout times obtained using Mei’s model and our model are compared. The results show that the proposed model is more compatible with physics and provides results that are more precise.

Novel Three-Dimensional Understanding of Maxillary Cleft Distraction.

Science.gov (United States)

Vaughan, Stephen Michael; Kau, Chung How; Waite, Peter Daniel

2016-09-01

To set forth a universal standard methodology for quantifying volumetric and linear changes in the craniofacial complex, utilizing three-dimensional data captured from a cleft-lip palate patient who underwent rigid external device (RED) distraction. Cone beam computed tomography images of a 14-year-old patient were captured using a Kodak 9500 (Atlanta, GA) Cone Beam system device and a stereophotogrammetric system (3dMDface(TM) Atlanta, GA). The subject was a nonsyndromic unilateral cleft-lip palate patient who received RED distraction as part of maxillary advancement in conjunction with orthodontic treatment. Preop (T1) and postop (T2) images were superimposed using Invivo 5.2.3 (San Jose, CA) software. Volumetric rendering of the airway, bone, and soft tissues, as well as linear measurements were analyzed. Each measurement was captured 10 times to ensure reliability and reproducibility of methodology. Data from T1 to T2 revealed mean differences as follows: airway total volume +5250 mm, minimum cross-sectional area +67.84 mm; bone +1719 mm, soft tissue +44,432 mm. Mean of linear measurements: Pronasale 1.98 mm, Subnasale 3.35 mm, Labial superius 10.79 mm, Labial inferius 4.13 mm, Right alare 5.71 mm, Right cheilion 7.83 mm, Left alare 4.97 mm, Left cheilion 5.50 mm, Pogonion 3.01 mm, B-point 2.49 mm, U1-U1 9.77 mm, and L1-L1 0.00 mm. P values are distractions in a three-dimensional format. A universal standard analysis of the craniofacial complex can be implemented using the techniques and method outlined in this study.

Three-dimensional structure of Rubella virus factories

International Nuclear Information System (INIS)

Fontana, Juan; Lopez-Iglesias, Carmen; Tzeng, Wen-Ping; Frey, Teryl K.; Fernandez, Jose J.; Risco, Cristina

2010-01-01

Viral factories are complex structures in the infected cell where viruses compartmentalize their life cycle. Rubella virus (RUBV) assembles factories by recruitment of rough endoplasmic reticulum (RER), mitochondria and Golgi around modified lysosomes known as cytopathic vacuoles or CPVs. These organelles contain active replication complexes that transfer replicated RNA to assembly sites in Golgi membranes. We have studied the structure of RUBV factory in three dimensions by electron tomography and freeze-fracture. CPVs contain stacked membranes, rigid sheets, small vesicles and large vacuoles. These membranes are interconnected and in communication with the endocytic pathway since they incorporate endocytosed BSA-gold. RER and CPVs are coupled through protein bridges and closely apposed membranes. Golgi vesicles attach to the CPVs but no tight contacts with mitochondria were detected. Immunogold labelling confirmed that the mitochondrial protein p32 is an abundant component around and inside CPVs where it could play important roles in factory activities.

Steady finite-Reynolds-number flows in three-dimensional collapsible tubes

Science.gov (United States)

Hazel, Andrew L.; Heil, Matthias

2003-07-01

A fully coupled finite-element method is used to investigate the steady flow of a viscous fluid through a thin-walled elastic tube mounted between two rigid tubes. The steady three-dimensional Navier Stokes equations are solved simultaneously with the equations of geometrically nonlinear Kirchhoff Love shell theory. If the transmural (internal minus external) pressure acting on the tube is sufficiently negative then the tube buckles non-axisymmetrically and the subsequent large deformations lead to a strong interaction between the fluid and solid mechanics. The main effect of fluid inertia on the macroscopic behaviour of the system is due to the Bernoulli effect, which induces an additional local pressure drop when the tube buckles and its cross-sectional area is reduced. Thus, the tube collapses more strongly than it would in the absence of fluid inertia. Typical tube shapes and flow fields are presented. In strongly collapsed tubes, at finite values of the Reynolds number, two ’jets‘ develop downstream of the region of strongest collapse and persist for considerable axial distances. For sufficiently high values of the Reynolds number, these jets impact upon the sidewalls and spread azimuthally. The consequent azimuthal transport of momentum dramatically changes the axial velocity profiles, which become approximately uTheta-shaped when the flow enters the rigid downstream pipe. Further convection of momentum causes the development of a ring-shaped velocity profile before the ultimate return to a parabolic profile far downstream.

Effects of emotional valence and three-dimensionality of visual stimuli on brain activation: an fMRI study.

Science.gov (United States)

Dores, A R; Almeida, I; Barbosa, F; Castelo-Branco, M; Monteiro, L; Reis, M; de Sousa, L; Caldas, A Castro

2013-01-01

Examining changes in brain activation linked with emotion-inducing stimuli is essential to the study of emotions. Due to the ecological potential of techniques such as virtual reality (VR), inspection of whether brain activation in response to emotional stimuli can be modulated by the three-dimensional (3D) properties of the images is important. The current study sought to test whether the activation of brain areas involved in the emotional processing of scenarios of different valences can be modulated by 3D. Therefore, the focus was made on the interaction effect between emotion-inducing stimuli of different emotional valences (pleasant, unpleasant and neutral valences) and visualization types (2D, 3D). However, main effects were also analyzed. The effect of emotional valence and visualization types and their interaction were analyzed through a 3 × 2 repeated measures ANOVA. Post-hoc t-tests were performed under a ROI-analysis approach. The results show increased brain activation for the 3D affective-inducing stimuli in comparison with the same stimuli in 2D scenarios, mostly in cortical and subcortical regions that are related to emotional processing, in addition to visual processing regions. This study has the potential of clarify brain mechanisms involved in the processing of emotional stimuli (scenarios' valence) and their interaction with three-dimensionality.

Three-dimensional particle image velocimetry measurement technique

International Nuclear Information System (INIS)

Hassan, Y.A.; Seeley, C.H.; Henderson, J.A.; Schmidl, W.D.

2004-01-01

The experimental flow visualization tool, Particle Image Velocimetry (PIV), is being used to determine the velocity field in two-dimensional fluid flows. In the past few years, the technique has been improved to allow the capture of flow fields in three dimensions. This paper describes changes which were made to two existing two-dimensional tracking algorithms to enable them to track three-dimensional PIV data. Results of the tests performed on these three-dimensional routines with synthetic data are presented. Experimental data was also used to test the tracking algorithms. The test setup which was used to acquire the three-dimensional experimental data is described, along with the results from both of the tracking routines which were used to analyze the experimental data. (author)

Structures of two-dimensional three-body systems

International Nuclear Information System (INIS)

Ruan, W.Y.; Liu, Y.Y.; Bao, C.G.

1996-01-01

Features of the structure of L = 0 states of a two-dimensional three-body model system have been investigated. Three types of permutation symmetry of the spatial part, namely symmetric, antisymmetric, and mixed, have been considered. A comparison has been made between the two-dimensional system and the corresponding three-dimensional one. The effect of symmetry on microscopic structures is emphasized. (author)

Self-assembled three-dimensional and compressible interdigitated thin-film supercapacitors and batteries

Science.gov (United States)

Nyström, Gustav; Marais, Andrew; Karabulut, Erdem; Wågberg, Lars; Cui, Yi; Hamedi, Mahiar M.

2015-01-01

Traditional thin-film energy-storage devices consist of stacked layers of active films on two-dimensional substrates and do not exploit the third dimension. Fully three-dimensional thin-film devices would allow energy storage in bulk materials with arbitrary form factors and with mechanical properties unique to bulk materials such as compressibility. Here we show three-dimensional energy-storage devices based on layer-by-layer self-assembly of interdigitated thin films on the surface of an open-cell aerogel substrate. We demonstrate a reversibly compressible three-dimensional supercapacitor with carbon nanotube electrodes and a three-dimensional hybrid battery with a copper hexacyanoferrate ion intercalating cathode and a carbon nanotube anode. The three-dimensional supercapacitor shows stable operation over 400 cycles with a capacitance of 25 F g−1 and is fully functional even at compressions up to 75%. Our results demonstrate that layer-by-layer self-assembly inside aerogels is a rapid, precise and scalable route for building high-surface-area 3D thin-film devices. PMID:26021485

Hydrodynamics of a three-dimensional self-propelled flexible plate

Science.gov (United States)

Ryu, Jaeha; Sung, Hyung Jin

2017-11-01

A three-dimensional self-propelled flexible plate in a quiescent flow was simulated using the immersed boundary method. The clamped leading edge of the flexible plate was forced into a vertical oscillation, while free to move horizontally. To reveal the hydrodynamics of the plate, the averaged cruising speed (UC) , the input power (P) , and the swimming efficiency (η) were analyzed as a function of the bending rigidity (γ) and the flapping frequency (f) . The velocity field around the plate and the exerted force on the plate were demonstrated to find out the dynamic interaction between the plate and the surrounding fluid. The kinematics of the plate, the maximum angle of attack (ϕmax) , and the mean effective length (Leff) were examined accounting for the hydrodynamics of the self-propelled flexible plate. The vortical structures around the plate were visualized, and the influence of the tip vortex on the swimming efficiency was explored qualitatively and quantitatively. This work was supported by the Creative Research Initiatives (No. 2017-013369) program of the National Research Foundation of Korea (MSIP).

Elastocapillary fabrication of three-dimensional microstructures

NARCIS (Netherlands)

van Honschoten, J.W.; Berenschot, Johan W.; Ondarcuhu, T.; Sanders, Remco G.P.; Sundaram, J.; Elwenspoek, Michael Curt; Tas, Niels Roelof

2010-01-01

We describe the fabrication of three-dimensional microstructures by means of capillary forces. Using an origami-like technique, planar silicon nitride structures of various geometries are folded to produce three-dimensional objects of 50–100 m. Capillarity is a particularly effective mechanism since

Numerical simulation of the control of the three-dimensional transition process in boundary layers

Science.gov (United States)

Kral, L. D.; Fasel, H. F.

1990-01-01

Surface heating techniques to control the three-dimensional laminar-turbulent transition process are numerically investigated for a water boundary layer. The Navier-Stokes and energy equations are solved using a fully implicit finite difference/spectral method. The spatially evolving boundary layer is simulated. Results of both passive and active methods of control are shown for small amplitude two-dimensional and three-dimensional disturbance waves. Control is also applied to the early stages of the secondary instability process using passive or active control techniques.

Three-dimensional structure of a pre-catalytic human spliceosomal complex B.

Science.gov (United States)

Boehringer, Daniel; Makarov, Evgeny M; Sander, Bjoern; Makarova, Olga V; Kastner, Berthold; Lührmann, Reinhard; Stark, Holger

2004-05-01

Major structural changes occur in the spliceosome during its transition from the fully assembled complex B to the catalytically activated spliceosome. To understand the rearrangement, it is necessary to know the detailed three-dimensional structures of these complexes. Here, we have immunoaffinity-purified human spliceosomes (designated B Delta U1) at a stage after U4/U6.U5 tri-snRNP integration but before activation, and have determined the three-dimensional structure of B Delta U1 by single-particle electron cryomicroscopy at a resolution of approximately 40 A. The overall size of the complex is about 370 x 270 x 170 A. The three-dimensional structure features a roughly triangular body linked to a head domain in variable orientations. The body is very similar in size and shape to the isolated U4/U6.U5 tri-snRNP. This provides initial insight into the structural organization of complex B.

Three-dimensional finite element impact analysis of a nuclear waste truck cask

International Nuclear Information System (INIS)

Miller, J.D.

1985-01-01

This paper presents a three-dimensional finite element impact analysis of a hypothetical accident event for the preliminary design of a shipping cask which is used to transport radioactive waste by standard tractor-semitrailer truck. The nonlinear dynamic structural analysis code DYNA3D run on Sandia's Cray-1 computer was used to calculate the effects of the cask's closure-end impacting a rigid frictionless surface on an edge of its external impact limiter after a 30-foot fall. The center of gravity of the cask (made of 304 stainless steel and depleted uranium) was assumed to be directly above the impact point. An elastic-plastic material constitutive model was used to calculate the nonlinear response of the cask components to the transient loading. Interactive color graphics (PATRAN and MOVIE BYU) were used throughout the analysis, proving to be extremely helpful for generation and verification of the geometry and boundary conditions of the finite element model and for interpretation of the analysis results. Results from the calculations show the cask sustained large localized deformations. However, these were almost entirely confined to the impact limiters built into the cask. The closure sections were determined to remain intact, and leakage would not be expected after the event. As an example of a large three-dimensional finite element dynamic impact calculation, this analysis can serve as an excellent benchmark for computer aided design procedures

A study of semi-rigid support on ankle supination sprain kinematics.

Science.gov (United States)

Tang, Y M; Wu, Z H; Liao, W H; Chan, K M

2010-12-01

Ankle sprain injury is very common in sports and the use of ankle support is crucial. This research investigated the effect of an ankle brace in reducing the ankle angular displacement and angular velocity during sudden supination. In the experiment, 11 healthy males were tested. The bracing condition, semi-rigid ankle braces were investigated. The angular displacement and angular velocity of the ankle were computed. The motion-capture system was adopted to capture the three-dimensional coordinates of the reflective markers. The coordinates of the reflective markers were used to compute the ankle kinematics during simulated ankle supination. A mechanical supination platform was used to simulate the sprain motions. Experimental results showed that the semi-rigid brace tested significantly reduced the ankle angular displacement and angular velocity compared with control conditions during sudden supination. In conclusion, the semi-rigid-type brace can provide significant restriction to reduce the magnitudes of the angular displacement and angular velocity of the ankle during sudden supination sprain. The semi-rigid-type brace is suggested as the prophylactic bracing for the ankle. © 2009 John Wiley & Sons A/S.

Quantum dynamics of water dissociative chemisorption on rigid Ni(111): An approximate nine-dimensional treatment

International Nuclear Information System (INIS)

Jiang, Bin; Song, Hongwei; Yang, Minghui; Guo, Hua

2016-01-01

The quantum dynamics of water dissociative chemisorption on the rigid Ni(111) surface is investigated using a recently developed nine-dimensional potential energy surface. The quantum dynamical model includes explicitly seven degrees of freedom of D 2 O at fixed surface sites, and the final results were obtained with a site-averaging model. The mode specificity in the site-specific results is reported and analyzed. Finally, the approximate sticking probabilities for various vibrationally excited states of D 2 O are obtained considering surface lattice effects and formally all nine degrees of freedom. The comparison with experiment reveals the inaccuracy of the density functional theory and suggests the need to improve the potential energy surface.

Three-dimensional printing and pediatric liver disease.

Science.gov (United States)

Alkhouri, Naim; Zein, Nizar N

2016-10-01

Enthusiastic physicians and medical researchers are investigating the role of three-dimensional printing in medicine. The purpose of the current review is to provide a concise summary of the role of three-dimensional printing technology as it relates to the field of pediatric hepatology and liver transplantation. Our group and others have recently demonstrated the feasibility of printing three-dimensional livers with identical anatomical and geometrical landmarks to the native liver to facilitate presurgical planning of complex liver surgeries. Medical educators are exploring the use of three-dimensional printed organs in anatomy classes and surgical residencies. Moreover, mini-livers are being developed by regenerative medicine scientist as a way to test new drugs and, eventually, whole livers will be grown in the laboratory to replace organs with end-stage disease solving the organ shortage problem. From presurgical planning to medical education to ultimately the bioprinting of whole organs for transplantation, three-dimensional printing will change medicine as we know in the next few years.

Visual Interpretation with Three-Dimensional Annotations (VITA): Three-Dimensional Image Interpretation Tool for Radiological Reporting

OpenAIRE

Roy, Sharmili; Brown, Michael S.; Shih, George L.

2013-01-01

This paper introduces a software framework called Visual Interpretation with Three-Dimensional Annotations (VITA) that is able to automatically generate three-dimensional (3D) visual summaries based on radiological annotations made during routine exam reporting. VITA summaries are in the form of rotating 3D volumes where radiological annotations are highlighted to place important clinical observations into a 3D context. The rendered volume is produced as a Digital Imaging and Communications i...

Near-field three-dimensional radar imaging techniques and applications.

Science.gov (United States)

Sheen, David; McMakin, Douglas; Hall, Thomas

2010-07-01

Three-dimensional radio frequency imaging techniques have been developed for a variety of near-field applications, including radar cross-section imaging, concealed weapon detection, ground penetrating radar imaging, through-barrier imaging, and nondestructive evaluation. These methods employ active radar transceivers that operate at various frequency ranges covering a wide range, from less than 100 MHz to in excess of 350 GHz, with the frequency range customized for each application. Computational wavefront reconstruction imaging techniques have been developed that optimize the resolution and illumination quality of the images. In this paper, rectilinear and cylindrical three-dimensional imaging techniques are described along with several application results.

A three-dimensional muscle activity imaging technique for assessing pelvic muscle function

Science.gov (United States)

Zhang, Yingchun; Wang, Dan; Timm, Gerald W.

2010-11-01

A novel multi-channel surface electromyography (EMG)-based three-dimensional muscle activity imaging (MAI) technique has been developed by combining the bioelectrical source reconstruction approach and subject-specific finite element modeling approach. Internal muscle activities are modeled by a current density distribution and estimated from the intra-vaginal surface EMG signals with the aid of a weighted minimum norm estimation algorithm. The MAI technique was employed to minimally invasively reconstruct electrical activity in the pelvic floor muscles and urethral sphincter from multi-channel intra-vaginal surface EMG recordings. A series of computer simulations were conducted to evaluate the performance of the present MAI technique. With appropriate numerical modeling and inverse estimation techniques, we have demonstrated the capability of the MAI technique to accurately reconstruct internal muscle activities from surface EMG recordings. This MAI technique combined with traditional EMG signal analysis techniques is being used to study etiologic factors associated with stress urinary incontinence in women by correlating functional status of muscles characterized from the intra-vaginal surface EMG measurements with the specific pelvic muscle groups that generated these signals. The developed MAI technique described herein holds promise for eliminating the need to place needle electrodes into muscles to obtain accurate EMG recordings in some clinical applications.

Stability Analysis Of 3-d Conventional Pallet Rack Structures With Semi-rigid Connections

Directory of Open Access Journals (Sweden)

Kamal M. Bajoria

2009-12-01

Full Text Available This paper describe the three dimensional finite element modeling and buckling analysis of conventional pallet racking system with semi rigid connection. In this study three dimensional models of conventional pallet racking system were prepared using the finiteelement program ANSYS and finite element analysis carried out on conventional pallet racks with the 18 types of column sections developed along with semi-rigid connections. A parametric study was carried out to compare the effective length approach and the finiteelement method for accuracy and appropriateness for cold-formed steel frame design. Numerous frame elastic buckling analyses were carried out to evaluate the alignment chart and the AISI torsional-flexural buckling provisions. The parameters that influence the valueof Kx for column flexural buckling were examined in this study. The alignment chart and the AISI torsional-flexural buckling provisions, used to obtain the effective lengths and elastic buckling load of members were also evaluated. Results showed that the elastic buckling load obtained from the AISI torsional-flexural buckling provisions is generally conservative compared to the results obtained from performing frame elastic buckling analysis. Results also showed that, the effective length approach is more conservative than the finite element approach.

Application of Simulated Three Dimensional CT Image in Orthognathic Surgery

Energy Technology Data Exchange (ETDEWEB)

Kim, Hyun Don; Park, Chang Seo [Dept. of Dental Radiology, College of Dentistry, Yensei University, Seoul (Korea, Republic of); Yoo, Sun Kook; Lee, Kyoung Sang [Dept. of Medical Engineering, College of Medicine, Yensei University, Seoul (Korea, Republic of)

1998-08-15

In orthodontics and orthognathic surgery, cephalogram has been routine practice in diagnosis and treatment evaluation of craniofacial deformity. But its inherent distortion of actual length and angles during projecting three dimensional object to two dimensional plane might cause errors in quantitative analysis of shape and size. Therefore, it is desirable that three dimensional object is diagnosed and evaluated three dimensionally and three dimensional CT image is best for three dimensional analysis. Development of clinic necessitates evaluation of result of treatment and comparison before and after surgery. It is desirable that patient that was diagnosed and planned by three dimensional computed tomography before surgery is evaluated by three dimensional computed tomography after surgery, too. But Because there is no standardized normal values in three dimension now and three dimensional Computed Tomography needs expensive equipment and because of its expenses and amount of exposure to radiation, limitations still remain to be solved in its application to routine practice. If postoperative three dimensional image is constructed by pre and postoperative lateral and postero-anterior cephalograms and preoperative three dimensional computed tomogram, pre and postoperative image will be compared and evaluated three dimensionally without three dimensional computed tomography after surgery and that will contribute to standardize normal values in three dimension. This study introduced new method that computer-simulated three dimensional image was constructed by preoperative three dimensional computed tomogram and pre and postoperative lateral and postero-anterior cephalograms, and for validation of new method, in four cases of dry skull that position of mandible was displaced and four patients of orthognathic surgery, computer-simulated three dimensional image and actual postoperative three dimensional image were compared. The results were as follows. 1. In four cases of

Application of Simulated Three Dimensional CT Image in Orthognathic Surgery

International Nuclear Information System (INIS)

Kim, Hyun Don; Park, Chang Seo; Yoo, Sun Kook; Lee, Kyoung Sang

1998-01-01

In orthodontics and orthognathic surgery, cephalogram has been routine practice in diagnosis and treatment evaluation of craniofacial deformity. But its inherent distortion of actual length and angles during projecting three dimensional object to two dimensional plane might cause errors in quantitative analysis of shape and size. Therefore, it is desirable that three dimensional object is diagnosed and evaluated three dimensionally and three dimensional CT image is best for three dimensional analysis. Development of clinic necessitates evaluation of result of treatment and comparison before and after surgery. It is desirable that patient that was diagnosed and planned by three dimensional computed tomography before surgery is evaluated by three dimensional computed tomography after surgery, too. But Because there is no standardized normal values in three dimension now and three dimensional Computed Tomography needs expensive equipment and because of its expenses and amount of exposure to radiation, limitations still remain to be solved in its application to routine practice. If postoperative three dimensional image is constructed by pre and postoperative lateral and postero-anterior cephalograms and preoperative three dimensional computed tomogram, pre and postoperative image will be compared and evaluated three dimensionally without three dimensional computed tomography after surgery and that will contribute to standardize normal values in three dimension. This study introduced new method that computer-simulated three dimensional image was constructed by preoperative three dimensional computed tomogram and pre and postoperative lateral and postero-anterior cephalograms, and for validation of new method, in four cases of dry skull that position of mandible was displaced and four patients of orthognathic surgery, computer-simulated three dimensional image and actual postoperative three dimensional image were compared. The results were as follows. 1. In four cases of

Rheology of three-dimensional packings of aggregates: microstructure and effects of nonconvexity.

Science.gov (United States)

Azéma, Emilien; Radjaï, Farhang; Saint-Cyr, Baptiste; Delenne, Jean-Yves; Sornay, Philippe

2013-05-01

We use three-dimensional contact dynamics simulations to analyze the rheological properties of granular materials composed of rigid aggregates. The aggregates are made from four overlapping spheres and described by a nonconvexity parameter depending on the relative positions of the spheres. The macroscopic and microstructural properties of several sheared packings are analyzed as a function of the degree of nonconvexity of the aggregates. We find that the internal angle of friction increases with the nonconvexity. In contrast, the packing fraction first increases to a maximum value but declines as the nonconvexity increases further. At a high level of nonconvexity, the packings are looser but show a higher shear strength. At the microscopic scale, the fabric and force anisotropy, as well as the friction mobilization, are enhanced by multiple contacts between aggregates and interlocking, thus revealings the mechanical and geometrical origins of shear strength.

Three-dimensional rearrangement of single atoms using actively controlled optical microtraps.

Science.gov (United States)

Lee, Woojun; Kim, Hyosub; Ahn, Jaewook

2016-05-02

We propose and demonstrate three-dimensional rearrangements of single atoms. In experiments performed with single 87Rb atoms in optical microtraps actively controlled by a spatial light modulator, we demonstrate various dynamic rearrangements of up to N = 9 atoms including rotation, 2D vacancy filling, guiding, compactification, and 3D shuffling. With the capability of a phase-only Fourier mask to generate arbitrary shapes of the holographic microtraps, it was possible to place single atoms at arbitrary geometries of a few μm size and even continuously reconfigure them by conveying each atom. For this purpose, we loaded a series of computer-generated phase masks in the full frame rate of 60 Hz of the spatial light modulator, so the animation of phase mask transformed the holographic microtraps in real time, driving each atom along the assigned trajectory. Possible applications of this method of transformation of single atoms include preparation of scalable quantum platforms for quantum computation, quantum simulation, and quantum many-body physics.

Three-dimensional low-energy topological invariants

International Nuclear Information System (INIS)

Bakalarska, M.; Broda, B.

2000-01-01

A description of the one-loop approximation formula for the partition function of a three-dimensional abelian version of the Donaldson-Witten theory is proposed. The one-loop expression is shown to contain such topological invariants of a three-dimensional manifold M like the Reidemeister-Ray-Singer torsion τ R and Betti numbers. (orig.)

Three-dimensional interconnected nickel phosphide networks with hollow microstructures and desulfurization performance

International Nuclear Information System (INIS)

Zhang, Shuna; Zhang, Shujuan; Song, Limin; Wu, Xiaoqing; Fang, Sheng

2014-01-01

Graphical abstract: Three-dimensional interconnected nickel phosphide networks with hollow microstructures and desulfurization performance. - Highlights: • Three-dimensional Ni 2 P has been prepared using foam nickel as a template. • The microstructures interconnected and formed sponge-like porous networks. • Three-dimensional Ni 2 P shows superior hydrodesulfurization activity. - Abstract: Three-dimensional microstructured nickel phosphide (Ni 2 P) was fabricated by the reaction between foam nickel (Ni) and phosphorus red. The as-prepared Ni 2 P samples, as interconnected networks, maintained the original mesh structure of foamed nickel. The crystal structure and morphology of the as-synthesized Ni 2 P were characterized by X-ray diffraction, scanning electron microscopy, automatic mercury porosimetry and X-ray photoelectron spectroscopy. The SEM study showed adjacent hollow branches were mutually interconnected to form sponge-like networks. The investigation on pore structure provided detailed information for the hollow microstructures. The growth mechanism for the three-dimensionally structured Ni 2 P was postulated and discussed in detail. To investigate its catalytic properties, SiO 2 supported three-dimensional Ni 2 P was prepared successfully and evaluated for the hydrodesulfurization (HDS) of dibenzothiophene (DBT). DBT molecules were mostly hydrogenated and then desulfurized by Ni 2 P/SiO 2

[Bone drilling simulation by three-dimensional imaging].

Science.gov (United States)

Suto, Y; Furuhata, K; Kojima, T; Kurokawa, T; Kobayashi, M

1989-06-01

The three-dimensional display technique has a wide range of medical applications. Pre-operative planning is one typical application: in orthopedic surgery, three-dimensional image processing has been used very successfully. We have employed this technique in pre-operative planning for orthopedic surgery, and have developed a simulation system for bone-drilling. Positive results were obtained by pre-operative rehearsal; when a region of interest is indicated by means of a mouse on the three-dimensional image displayed on the CRT, the corresponding region appears on the slice image which is displayed simultaneously. Consequently, the status of the bone-drilling is constantly monitored. In developing this system, we have placed emphasis on the quality of the reconstructed three-dimensional images, on fast processing, and on the easy operation of the surgical planning simulation.

Three-Dimensional Printing Surgical Applications.

Science.gov (United States)

AlAli, Ahmad B; Griffin, Michelle F; Butler, Peter E

2015-01-01

Three-dimensional printing, a technology used for decades in the industrial field, gains a lot of attention in the medical field for its potential benefits. With advancement of desktop printers, this technology is accessible and a lot of research is going on in the medical field. To evaluate its application in surgical field, which may include but not limited to surgical planning, surgical education, implants, and prosthesis, which are the focus of this review. Research was conducted by searching PubMed, Web of science, and other reliable sources. We included original articles and excluded articles based on animals, those more than 10 years old, and those not in English. These articles were evaluated, and relevant studies were included in this review. Three-dimensional printing shows a potential benefit in surgical application. Printed implants were used in patient in a few cases and show successful results; however, longer follow-up and more trials are needed. Surgical and medical education is believed to be more efficient with this technology than the current practice. Printed surgical instrument and surgical planning are also believed to improve with three-dimensional printing. Three-dimensional printing can be a very powerful tool in the near future, which can aid the medical field that is facing a lot of challenges and obstacles. However, despite the reported results, further research on larger samples and analytical measurements should be conducted to ensure this technology's impact on the practice.

The Three-dimensional Digital Factory for Shipbuilding Technology Research

Directory of Open Access Journals (Sweden)

Xu Wei

2016-01-01

Full Text Available The three-dimensional digital factory technology research is the hotspot in shipbuilding recently. The three-dimensional digital factory technology not only focus on design the components of the product, but also discuss on the simulation and analyses of the production process.Based on the three-dimensional model, the basic data layer, application control layer and the presentation layer of hierarchical structure are established in the three-dimensional digital factory of shipbuilding in this paper. And the key technologies of three-dimensional digital factory of shipbuilding are analysed. Finally, a case study is applied and the results show that the three-dimensional digital factory will play an important role in the future.

Towards three-dimensional optical metamaterials

Science.gov (United States)

Tanaka, Takuo; Ishikawa, Atsushi

2017-12-01

Metamaterials have opened up the possibility of unprecedented and fascinating concepts and applications in optics and photonics. Examples include negative refraction, perfect lenses, cloaking, perfect absorbers, and so on. Since these metamaterials are man-made materials composed of sub-wavelength structures, their development strongly depends on the advancement of micro- and nano-fabrication technologies. In particular, the realization of three-dimensional metamaterials is one of the big challenges in this research field. In this review, we describe recent progress in the fabrication technologies for three-dimensional metamaterials, as well as proposed applications.

Three-dimensional imaging modalities in endodontics

Science.gov (United States)

Mao, Teresa

2014-01-01

Recent research in endodontics has highlighted the need for three-dimensional imaging in the clinical arena as well as in research. Three-dimensional imaging using computed tomography (CT) has been used in endodontics over the past decade. Three types of CT scans have been studied in endodontics, namely cone-beam CT, spiral CT, and peripheral quantitative CT. Contemporary endodontics places an emphasis on the use of cone-beam CT for an accurate diagnosis of parameters that cannot be visualized on a two-dimensional image. This review discusses the role of CT in endodontics, pertaining to its importance in the diagnosis of root canal anatomy, detection of peri-radicular lesions, diagnosis of trauma and resorption, presurgical assessment, and evaluation of the treatment outcome. PMID:25279337

Three-dimensional imaging modalities in endodontics

Energy Technology Data Exchange (ETDEWEB)

Mao, Teresa; Neelakantan, Prasanna [Dept. of Conservative Dentistry and Endodontics, Saveetha Dental College and Hospitals, Saveetha University, Chennai (India)

2014-09-15

Recent research in endodontics has highlighted the need for three-dimensional imaging in the clinical arena as well as in research. Three-dimensional imaging using computed tomography (CT) has been used in endodontics over the past decade. Three types of CT scans have been studied in endodontics, namely cone-beam CT, spiral CT, and peripheral quantitative CT. Contemporary endodontics places an emphasis on the use of cone-beam CT for an accurate diagnosis of parameters that cannot be visualized on a two-dimensional image. This review discusses the role of CT in endodontics, pertaining to its importance in the diagnosis of root canal anatomy, detection of peri-radicular lesions, diagnosis of trauma and resorption, presurgical assessment, and evaluation of the treatment outcome.

Three-dimensional imaging modalities in endodontics

International Nuclear Information System (INIS)

Mao, Teresa; Neelakantan, Prasanna

2014-01-01

Recent research in endodontics has highlighted the need for three-dimensional imaging in the clinical arena as well as in research. Three-dimensional imaging using computed tomography (CT) has been used in endodontics over the past decade. Three types of CT scans have been studied in endodontics, namely cone-beam CT, spiral CT, and peripheral quantitative CT. Contemporary endodontics places an emphasis on the use of cone-beam CT for an accurate diagnosis of parameters that cannot be visualized on a two-dimensional image. This review discusses the role of CT in endodontics, pertaining to its importance in the diagnosis of root canal anatomy, detection of peri-radicular lesions, diagnosis of trauma and resorption, presurgical assessment, and evaluation of the treatment outcome

A three-dimensional field solutions of Halbach

International Nuclear Information System (INIS)

Chen Jizhong; Xiao Jijun; Zhang Yiming; Xu Chunyan

2008-01-01

A three-dimensional field solutions are presented for Halback cylinder magnet. Based on Ampere equivalent current methods, the permanent magnets are taken as distributing of current density. For getting the three-dimensional field solution of ideal polarized permanent magnets, the solution method entails the use of the vector potential and involves the closed-form integration of the free-space Green's function. The programmed field solution are ideal for performing rapid parametric studies of the dipole Halback cylinder magnets made from rare earth materials. The field solutions are verified by both an analytical two-dimensional algorithm and three-dimensional finite element software. A rapid method is presented for extensive analyzing and optimizing Halbach cylinder magnet. (authors)

Three Dimensional Dirac Semimetals

Science.gov (United States)

Zaheer, Saad

2014-03-01

Dirac points on the Fermi surface of two dimensional graphene are responsible for its unique electronic behavior. One can ask whether any three dimensional materials support similar pseudorelativistic physics in their bulk electronic spectra. This possibility has been investigated theoretically and is now supported by two successful experimental demonstrations reported during the last year. In this talk, I will summarize the various ways in which Dirac semimetals can be realized in three dimensions with primary focus on a specific theory developed on the basis of representations of crystal spacegroups. A three dimensional Dirac (Weyl) semimetal can appear in the presence (absence) of inversion symmetry by tuning parameters to the phase boundary separating a bulk insulating and a topological insulating phase. More generally, we find that specific rules governing crystal symmetry representations of electrons with spin lead to robust Dirac points at high symmetry points in the Brillouin zone. Combining these rules with microscopic considerations identifies six candidate Dirac semimetals. Another method towards engineering Dirac semimetals involves combining crystal symmetry and band inversion. Several candidate materials have been proposed utilizing this mechanism and one of the candidates has been successfully demonstrated as a Dirac semimetal in two independent experiments. Work carried out in collaboration with: Julia A. Steinberg, Steve M. Young, J.C.Y. Teo, C.L. Kane, E.J. Mele and Andrew M. Rappe.

Three-dimensional sea-urchin-like hierarchical TiO{sub 2} microspheres synthesized by a one-pot hydrothermal method and their enhanced photocatalytic activity

Energy Technology Data Exchange (ETDEWEB)

Zhou, Yi, E-mail: zhouyihn@163.com [Department of Chemical and Biological Engineering, Changsha University of Science and Technology, Hunan, 410114 (China); Huang, Yan; Li, Dang; He, Wenhong [Department of Chemical and Biological Engineering, Changsha University of Science and Technology, Hunan, 410114 (China)

2013-07-15

Graphical abstract: SEM images of the samples synthesized at different hydrothermal temperatures for 8 h: (a) 75; (b) 100; (c) 120; and (d) 140°C, followed by calcination at 450 °C for 2 h. Highlights: ► Effects of calcination temperature on the phase transformation were studied. ► Effects of hydrothermal temperature and time on the morphology growth were studied. ► A two-stage reaction mechanism for the formation was presented. ► The photocatalytic activity was evaluated under sunlight irradiation. ► Effects of calcination temperature on the photocatalytic activity were studied. - Abstract: Novel three-dimensional sea-urchin-like hierarchical TiO{sub 2} superstructures were synthesized on a Ti plate in a mixture of H{sub 2}O{sub 2} and NaOH aqueous solution by a facile one-pot hydrothermal method at a low temperature, followed by protonation and calcination. The results of series of electron microscopy characterizations suggested that the hierarchical TiO{sub 2} superstructures consisted of numerous one-dimensional nanostructures. The microspheres were approximately 2–4 μm in diameter, and the one-dimensional TiO{sub 2} nanostructures were up to 600–700 nm long. A two-stage reaction mechanism, i.e., initial growth and then assembly, was proposed for the formation of these architectures. The three-dimensional sea-urchin-like hierarchical TiO{sub 2} microstructures showed excellent photocatalytic activity for the degradation of Rhodamine B aqueous solution under sunlight irradiation, which was attributed to the special three-dimensional hierarchical superstructure, and increased number of surface active sites. This novel superstructure has promising use in practical aqueous purification.

Three-dimensional instability of standing waves

Science.gov (United States)

Zhu, Qiang; Liu, Yuming; Yue, Dick K. P.

2003-12-01

We investigate the three-dimensional instability of finite-amplitude standing surface waves under the influence of gravity. The analysis employs the transition matrix (TM) approach and uses a new high-order spectral element (HOSE) method for computation of the nonlinear wave dynamics. HOSE is an extension of the original high-order spectral method (HOS) wherein nonlinear wave wave and wave body interactions are retained up to high order in wave steepness. Instead of global basis functions in HOS, however, HOSE employs spectral elements to allow for complex free-surface geometries and surface-piercing bodies. Exponential convergence of HOS with respect to the total number of spectral modes (for a fixed number of elements) and interaction order is retained in HOSE. In this study, we use TM-HOSE to obtain the stability of general three-dimensional perturbations (on a two-dimensional surface) on two classes of standing waves: plane standing waves in a rectangular tank; and radial/azimuthal standing waves in a circular basin. For plane standing waves, we confirm the known result of two-dimensional side-bandlike instability. In addition, we find a novel three-dimensional instability for base flow of any amplitude. The dominant component of the unstable disturbance is an oblique (standing) wave oriented at an arbitrary angle whose frequency is close to the (nonlinear) frequency of the original standing wave. This finding is confirmed by direct long-time simulations using HOSE which show that the nonlinear evolution leads to classical Fermi Pasta Ulam recurrence. For the circular basin, we find that, beyond a threshold wave steepness, a standing wave (of nonlinear frequency Omega) is unstable to three-dimensional perturbations. The unstable perturbation contains two dominant (standing-wave) components, the sum of whose frequencies is close to 2Omega. From the cases we consider, the critical wave steepness is found to generally decrease/increase with increasing radial

Analogy and Dynamic Geometry System Used to Introduce Three-Dimensional Geometry

Science.gov (United States)

Mammana, M. F.; Micale, B.; Pennisi, M.

2012-01-01

We present a sequence of classroom activities on Euclidean geometry, both plane and space geometry, used to make three dimensional geometry more catchy and simple. The activity consists of a guided research activity that leads the students to discover unexpected properties of two apparently distant geometrical entities, quadrilaterals and…

Cylindrical Three-Dimensional Porous Anodic Alumina Networks

Directory of Open Access Journals (Sweden)

Pedro M. Resende

2016-11-01

Full Text Available The synthesis of a conformal three-dimensional nanostructure based on porous anodic alumina with transversal nanopores on wires is herein presented. The resulting three-dimensional network exhibits the same nanostructure as that obtained on planar geometries, but with a macroscopic cylindrical geometry. The morphological analysis of the nanostructure revealed the effects of the initial defects on the aluminum surface and the mechanical strains on the integrity of the three-dimensional network. The results evidence the feasibility of obtaining 3D porous anodic alumina on non-planar aluminum substrates.

Multiparallel Three-Dimensional Optical Microscopy

Science.gov (United States)

Nguyen, Lam K.; Price, Jeffrey H.; Kellner, Albert L.; Bravo-Zanoquera, Miguel

2010-01-01

Multiparallel three-dimensional optical microscopy is a method of forming an approximate three-dimensional image of a microscope sample as a collection of images from different depths through the sample. The imaging apparatus includes a single microscope plus an assembly of beam splitters and mirrors that divide the output of the microscope into multiple channels. An imaging array of photodetectors in each channel is located at a different distance along the optical path from the microscope, corresponding to a focal plane at a different depth within the sample. The optical path leading to each photodetector array also includes lenses to compensate for the variation of magnification with distance so that the images ultimately formed on all the photodetector arrays are of the same magnification. The use of optical components common to multiple channels in a simple geometry makes it possible to obtain high light-transmission efficiency with an optically and mechanically simple assembly. In addition, because images can be read out simultaneously from all the photodetector arrays, the apparatus can support three-dimensional imaging at a high scanning rate.

Water dissociating on rigid Ni(100): A quantum dynamics study on a full-dimensional potential energy surface

Science.gov (United States)

Liu, Tianhui; Chen, Jun; Zhang, Zhaojun; Shen, Xiangjian; Fu, Bina; Zhang, Dong H.

2018-04-01

We constructed a nine-dimensional (9D) potential energy surface (PES) for the dissociative chemisorption of H2O on a rigid Ni(100) surface using the neural network method based on roughly 110 000 energies obtained from extensive density functional theory (DFT) calculations. The resulting PES is accurate and smooth, based on the small fitting errors and the good agreement between the fitted PES and the direct DFT calculations. Time dependent wave packet calculations also showed that the PES is very well converged with respect to the fitting procedure. The dissociation probabilities of H2O initially in the ground rovibrational state from 9D quantum dynamics calculations are quite different from the site-specific results from the seven-dimensional (7D) calculations, indicating the importance of full-dimensional quantum dynamics to quantitatively characterize this gas-surface reaction. It is found that the validity of the site-averaging approximation with exact potential holds well, where the site-averaging dissociation probability over 15 fixed impact sites obtained from 7D quantum dynamics calculations can accurately approximate the 9D dissociation probability for H2O in the ground rovibrational state.

Backlund transformations and three-dimensional lattice equations

NARCIS (Netherlands)

Nijhoff, F.W.; Capel, H.W.; Wiersma, G.L.; Quispel, G.R.W.

1984-01-01

A (nonlocal) linear integral equation is studied, which allows for Bäcklund transformations in the measure. The compatibility of three of these transformations leads to an integrable nonlinear three-dimensional lattice equation. In appropriate continuum limits the two-dimensional Toda-lattice

Arching in three-dimensional clogging

Science.gov (United States)

Török, János; Lévay, Sára; Szabó, Balázs; Somfai, Ellák; Wegner, Sandra; Stannarius, Ralf; Börzsönyi, Tamás

2017-06-01

Arching in dry granular material is a long established concept, however it remains still an open question how three-dimensional orifices clog. We investigate by means of numerical simulations and experimental data how the outflow creates a blocked configuration of particles. We define the concave surface of the clogged dome by two independent methods (geometric and density based). The average shape of the cupola for spheres is almost a hemisphere but individual samples have large holes in the structure indicating a blocked state composed of two-dimensional force chains rather than three-dimensional objects. The force chain structure justifies this assumption. For long particles the clogged configurations display large variations, and in certain cases the empty region reaches a height of 5 hole diameters. These structures involve vertical walls consisting of horizontally placed stable stacking of particles.

Three-dimensional reconstruction of the biliary tract using spiral computed tomography. Three-dimensional cholangiography

International Nuclear Information System (INIS)

Gon, Masanori; Ogura, Norihiro; Uetsuji, Shouji; Ueyama, Yasuo

1995-01-01

In this study, 310 patients with benign biliary diseases, 20 with gallbladder cancer, and 8 with biliary tract carcinoma underwent spiral CT (SCT) scanning at cholangiography. Depiction rate of the shape of the conjunction site of the gallbladder and biliary tract was 27.5% by conventional intravenous cholangiography (DIC), 92.5% by ERC, and 90.0% by DIC-SCT. Abnormal cystic duct course was admitted in 14.1%. Multiplanar reconstruction by DIC-SCT enabled identification of the common bile duct and intrahepatic bile duct stone. Three-dimensional reconstruction of DIC-SCT was effective in evaluating obstruction of the anastomosis or passing condition of after hepatico-jejunostomy. Two-dimensional SCT images through PTCD tube enabled degree of hepatic invasion in bile duct cancer, and three-dimensional images were useful in grasping the morphology of the bile duct branches near the obstruction site. DIC-SCT is therefore considered a useful procedure as non-invasive examination of bile duct lesions. (S.Y.)

Construction simulation analysis of 120m continuous rigid frame bridge based on Midas Civil

Science.gov (United States)

Shi, Jing-xian; Ran, Zhi-hong

2018-03-01

In this paper, a three-dimensional finite element model of a continuous rigid frame bridge with a main span of 120m is established by the simulation and analysis of Midas Civil software. The deflection and stress of the main beam in each construction stage of continuous beam bridge are simulated and analyzed, which provides a reliable technical guarantee for the safe construction of the bridge.

Rigidity-tuning conductive elastomer

Science.gov (United States)

Shan, Wanliang; Diller, Stuart; Tutcuoglu, Abbas; Majidi, Carmel

2015-06-01

We introduce a conductive propylene-based elastomer (cPBE) that rapidly and reversibly changes its mechanical rigidity when powered with electrical current. The elastomer is rigid in its natural state, with an elastic (Young’s) modulus of 175.5 MPa, and softens when electrically activated. By embedding the cPBE in an electrically insulating sheet of polydimethylsiloxane (PDMS), we create a cPBE-PDMS composite that can reversibly change its tensile modulus between 37 and 1.5 MPa. The rigidity change takes ˜6 s and is initiated when a 100 V voltage drop is applied across the two ends of the cPBE film. This magnitude of change in elastic rigidity is similar to that observed in natural skeletal muscle and catch connective tissue. We characterize the tunable load-bearing capability of the cPBE-PDMS composite with a motorized tensile test and deadweight experiment. Lastly, we demonstrate the ability to control the routing of internal forces by embedding several cPBE-PDMS ‘active tendons’ into a soft robotic pneumatic bending actuator. Selectively activating the artificial tendons controls the neutral axis and direction of bending during inflation.

Rigidity-tuning conductive elastomer

International Nuclear Information System (INIS)

Shan, Wanliang; Diller, Stuart; Tutcuoglu, Abbas; Majidi, Carmel

2015-01-01

We introduce a conductive propylene-based elastomer (cPBE) that rapidly and reversibly changes its mechanical rigidity when powered with electrical current. The elastomer is rigid in its natural state, with an elastic (Young’s) modulus of 175.5 MPa, and softens when electrically activated. By embedding the cPBE in an electrically insulating sheet of polydimethylsiloxane (PDMS), we create a cPBE–PDMS composite that can reversibly change its tensile modulus between 37 and 1.5 MPa. The rigidity change takes ∼6 s and is initiated when a 100 V voltage drop is applied across the two ends of the cPBE film. This magnitude of change in elastic rigidity is similar to that observed in natural skeletal muscle and catch connective tissue. We characterize the tunable load-bearing capability of the cPBE–PDMS composite with a motorized tensile test and deadweight experiment. Lastly, we demonstrate the ability to control the routing of internal forces by embedding several cPBE–PDMS ‘active tendons’ into a soft robotic pneumatic bending actuator. Selectively activating the artificial tendons controls the neutral axis and direction of bending during inflation. (paper)

Physical Webbing: Collaborative Kinesthetic Three-Dimensional Mind Maps[R

Science.gov (United States)

Williams, Marian H.

2012-01-01

Mind Mapping has predominantly been used by individuals or collaboratively in groups as a paper-based or computer-generated learning strategy. In an effort to make Mind Mapping kinesthetic, collaborative, and three-dimensional, an innovative pedagogical strategy, termed Physical Webbing, was devised. In the Physical Web activity, groups…

Three-dimensional appearance of the lips muscles with three-dimensional isotropic MRI: in vivo study

Energy Technology Data Exchange (ETDEWEB)

Olszewski, Raphael; Reychler, H. [Universite Catholique de Louvain, Department of Oral and Maxillofacial Surgery, Cliniques Universitaires Saint Luc, Brussels (Belgium); Liu, Y.; Xu, T.M. [Peking University School and Hospital of Stomatology, Department of Orthodontics, Beijing (China); Duprez, T. [Universite Catholique de Louvain, Department of Radiology, Cliniques Universitaires Saint Luc, Brussels (Belgium)

2009-06-15

Our knowledge of facial muscles is based primarily on atlases and cadaveric studies. This study describes a non-invasive in vivo method (3D MRI) for segmenting and reconstructing facial muscles in a three-dimensional fashion. Three-dimensional (3D), T1-weighted, 3 Tesla, isotropic MRI was applied to a subject. One observer performed semi-automatic segmentation using the Editor module from the 3D Slicer software (Harvard Medical School, Boston, MA, USA), version 3.2. We were able to successfully outline and three-dimensionally reconstruct the following facial muscles: pars labialis orbicularis oris, m. levatro labii superioris alaeque nasi, m. levator labii superioris, m. zygomaticus major and minor, m. depressor anguli oris, m. depressor labii inferioris, m. mentalis, m. buccinator, and m. orbicularis oculi. 3D reconstruction of the lip muscles should be taken into consideration in order to improve the accuracy and individualization of existing 3D facial soft tissue models. More studies are needed to further develop efficient methods for segmentation in this field. (orig.)

Three-dimensional appearance of the lips muscles with three-dimensional isotropic MRI: in vivo study.

Science.gov (United States)

Olszewski, Raphael; Liu, Y; Duprez, T; Xu, T M; Reychler, H

2009-06-01

Our knowledge of facial muscles is based primarily on atlases and cadaveric studies. This study describes a non-invasive in vivo method (3D MRI) for segmenting and reconstructing facial muscles in a three-dimensional fashion. Three-dimensional (3D), T1-weighted, 3 Tesla, isotropic MRI was applied to a subject. One observer performed semi-automatic segmentation using the Editor module from the 3D Slicer software (Harvard Medical School, Boston, MA, USA), version 3.2. We were able to successfully outline and three-dimensionally reconstruct the following facial muscles: pars labialis orbicularis oris, m. levatro labii superioris alaeque nasi, m. levator labii superioris, m. zygomaticus major and minor, m. depressor anguli oris, m. depressor labii inferioris, m. mentalis, m. buccinator, and m. orbicularis oculi. 3D reconstruction of the lip muscles should be taken into consideration in order to improve the accuracy and individualization of existing 3D facial soft tissue models. More studies are needed to further develop efficient methods for segmentation in this field.

Three-Dimensional Messages for Interstellar Communication

Science.gov (United States)

Vakoch, Douglas A.

One of the challenges facing independently evolved civilizations separated by interstellar distances is to communicate information unique to one civilization. One commonly proposed solution is to begin with two-dimensional pictorial representations of mathematical concepts and physical objects, in the hope that this will provide a foundation for overcoming linguistic barriers. However, significant aspects of such representations are highly conventional, and may not be readily intelligible to a civilization with different conventions. The process of teaching conventions of representation may be facilitated by the use of three-dimensional representations redundantly encoded in multiple formats (e.g., as both vectors and as rasters). After having illustrated specific conventions for representing mathematical objects in a three-dimensional space, this method can be used to describe a physical environment shared by transmitter and receiver: a three-dimensional space defined by the transmitter--receiver axis, and containing stars within that space. This method can be extended to show three-dimensional representations varying over time. Having clarified conventions for representing objects potentially familiar to both sender and receiver, novel objects can subsequently be depicted. This is illustrated through sequences showing interactions between human beings, which provide information about human behavior and personality. Extensions of this method may allow the communication of such culture-specific features as aesthetic judgments and religious beliefs. Limitations of this approach will be noted, with specific reference to ETI who are not primarily visual.

Three-dimensional topological insulators and bosonization

Energy Technology Data Exchange (ETDEWEB)

Cappelli, Andrea [INFN, Sezione di Firenze,Via G. Sansone 1, 50019 Sesto Fiorentino - Firenze (Italy); Randellini, Enrico [INFN, Sezione di Firenze,Via G. Sansone 1, 50019 Sesto Fiorentino - Firenze (Italy); Dipartimento di Fisica e Astronomia, Università di Firenze,Via G. Sansone 1, 50019 Sesto Fiorentino - Firenze (Italy); Sisti, Jacopo [Scuola Internazionale Superiore di Studi Avanzati (SISSA),Via Bonomea 265, 34136 Trieste (Italy)

2017-05-25

Massless excitations at the surface of three-dimensional time-reversal invariant topological insulators possess both fermionic and bosonic descriptions, originating from band theory and hydrodynamic BF theory, respectively. We analyze the corresponding field theories of the Dirac fermion and compactified boson and compute their partition functions on the three-dimensional torus geometry. We then find some non-dynamic exact properties of bosonization in (2+1) dimensions, regarding fermion parity and spin sectors. Using these results, we extend the Fu-Kane-Mele stability argument to fractional topological insulators in three dimensions.

Rigidity of outermost MOTS: the initial data version

Science.gov (United States)

Galloway, Gregory J.

2018-03-01

In the paper Commun Anal Geom 16(1):217-229, 2008, a rigidity result was obtained for outermost marginally outer trapped surfaces (MOTSs) that do not admit metrics of positive scalar curvature. This allowed one to treat the "borderline case" in the author's work with R. Schoen concerning the topology of higher dimensional black holes (Commun Math Phys 266(2):571-576, 2006). The proof of this rigidity result involved bending the initial data manifold in the vicinity of the MOTS within the ambient spacetime. In this note we show how to circumvent this step, and thereby obtain a pure initial data version of this rigidity result and its consequence concerning the topology of black holes.

High-resolution three-dimensional mapping of semiconductor dopant potentials

DEFF Research Database (Denmark)

Twitchett, AC; Yates, TJV; Newcomb, SB

2007-01-01

Semiconductor device structures are becoming increasingly three-dimensional at the nanometer scale. A key issue that must be addressed to enable future device development is the three-dimensional mapping of dopant distributions, ideally under "working conditions". Here we demonstrate how a combin......Semiconductor device structures are becoming increasingly three-dimensional at the nanometer scale. A key issue that must be addressed to enable future device development is the three-dimensional mapping of dopant distributions, ideally under "working conditions". Here we demonstrate how...... a combination of electron holography and electron tomography can be used to determine quantitatively the three-dimensional electrostatic potential in an electrically biased semiconductor device with nanometer spatial resolution....

Equilibrium: three-dimensional configurations

International Nuclear Information System (INIS)

Anon.

1987-01-01

This chapter considers toroidal MHD configurations that are inherently three-dimensional. The motivation for investigation such complicated equilibria is that they possess the potential for providing toroidal confinement without the need of a net toroidal current. This leads to a number of advantages with respect to fusion power generation. First, the attractive feature of steady-state operation becomes more feasible since such configurations no longer require a toroidal current transformer. Second, with zero net current, one potentially dangerous class of MHD instabilities, the current-driven kink modes, is eliminated. Finally, three-dimensional configurations possess nondegenerate flux surfaces even in the absence of plasma pressure and plasma current. Although there is an enormous range of possible three-dimensional equilibria, the configurations of interest are accurately described as axisymmetric tori with superimposed helical fields; furthermore, they possess no net toroidal current. Instead, two different and less obvious restoring forces are developed: the helical sideband force and the toroidal dipole current force. Each is discussed in detail in Chapter 7. A detailed discussion of the parallel current constraint, including its physical significance, is given in section 7.2. A general analysis of helical sideband equilibria, along with a detailed description of the Elmo bumpy torus, is presented in sections 7.3 and 7.4. A general description of toroidal dipole-current equilibria, including a detailed discussion of stellarators, heliotrons, and torsatrons, is given in sections 7.5 and 7.6

Volume scanning three-dimensional display with an inclined two-dimensional display and a mirror scanner

Science.gov (United States)

Miyazaki, Daisuke; Kawanishi, Tsuyoshi; Nishimura, Yasuhiro; Matsushita, Kenji

2001-11-01

A new three-dimensional display system based on a volume-scanning method is demonstrated. To form a three-dimensional real image, an inclined two-dimensional image is rapidly moved with a mirror scanner while the cross-section patterns of a three-dimensional object are displayed sequentially. A vector-scan CRT display unit is used to obtain a high-resolution image. An optical scanning system is constructed with concave mirrors and a galvanometer mirror. It is confirmed that three-dimensional images, formed by the experimental system, satisfy all the criteria for human stereoscopic vision.

Three-dimensional bio-printing.

Science.gov (United States)

Gu, Qi; Hao, Jie; Lu, YangJie; Wang, Liu; Wallace, Gordon G; Zhou, Qi

2015-05-01

Three-dimensional (3D) printing technology has been widely used in various manufacturing operations including automotive, defence and space industries. 3D printing has the advantages of personalization, flexibility and high resolution, and is therefore becoming increasingly visible in the high-tech fields. Three-dimensional bio-printing technology also holds promise for future use in medical applications. At present 3D bio-printing is mainly used for simulating and reconstructing some hard tissues or for preparing drug-delivery systems in the medical area. The fabrication of 3D structures with living cells and bioactive moieties spatially distributed throughout will be realisable. Fabrication of complex tissues and organs is still at the exploratory stage. This review summarize the development of 3D bio-printing and its potential in medical applications, as well as discussing the current challenges faced by 3D bio-printing.

Friction effects on lateral loading behavior of rigid piles

DEFF Research Database (Denmark)

Zania, Varvara; Hededal, Ole

2012-01-01

taking into account the shear frictional resistance along the pile. For this purpose efficient three dimensional finite element models of different diameter have been developed. The increase of the side friction and of the diameter of the pile is shown to alter the failure pattern and increase...... the lateral capacity of the pile. The obtained p - y curves demonstrate the importance of the aforementioned parameters in the design of rigid piles, as the reduction of friction along the interface reduces not only the ultimate load but also the stiffness of the soil-pile response. Read More: http...

Acid-base properties of complexes with three-dimensional polyligands. Complexes with three-dimensional polyphosphoric acids

International Nuclear Information System (INIS)

Kopylova, V.D.; Bojko, Eh.T.; Saldadze, K.M.

1985-01-01

By the method of potentiometric titration acid-base properties of uranyl (2) complexes with three-dimensional polyphosphoric acids, KRF-8p, KF-1, KF-7 prepared by phosphorylation of copolymer of styrene and divinylbenzene or saponification of the copolymers of di-2,2'-chloroethyl ester of vinylphosphonic acid with divinyl benzene are studied. It is shown that in case of formation in the phase of three-dimensional polyphosphoric acids of UO 2 2+ complexes with the growth of bond covalence of metal ion-phosphonic group the acidjty of the second hydroxyl of the phosphonic group increases

Three dimensional periodic foundations for base seismic isolation

International Nuclear Information System (INIS)

Yan, Y; Mo, Y L; Cheng, Z; Shi, Z; Menq, F; Tang, Y

2015-01-01

Based on the concept of phononic crystals, periodic foundations made of periodic materials are investigated in this paper. The periodic foundations can provide low frequency band gaps, which cover the main frequency ranges of seismic waves. Therefore, the periodic foundations are able to protect the upper structures during earthquake events. In this paper, the basic theory of three dimensional periodic foundations is studied and the finite element method was used to conduct the sensitivity study. A simplified three-dimensional periodic foundation with a superstructure was tested in the field and the feasibility of three dimensional periodic foundations was proved. The test results showed that the response of the upper structure with the three dimensional periodic foundation was reduced under excitation waves with the main frequency falling in the attenuation zones. The finite element analysis results are consistent with the experimental data, indicating that three dimensional periodic foundations are a feasible way of reducing seismic vibrations. (paper)

Electronic structures and three-dimensional effects of boron-doped carbon nanotubes

International Nuclear Information System (INIS)

Koretsune, Takashi; Saito, Susumu

2008-01-01

We study boron-doped carbon nanotubes by first-principles methods based on the density functional theory. To discuss the possibility of superconductivity, we calculate the electronic band structure and the density of states (DOS) of boron-doped (10,0) nanotubes by changing the boron density. It is found that the Fermi level density of states D(ε F ) increases upon lowering the boron density. This can be understood in terms of the rigid band picture where the one-dimensional van Hove singularity lies at the edge of the valence band in the DOS of the pristine nanotube. The effect of three-dimensionality is also considered by performing the calculations for bundled (10,0) nanotubes and boron-doped double-walled carbon nanotubes (10,0)/(19,0). From the calculation of the bundled nanotubes, it is found that interwall dispersion is sufficiently large to broaden the peaks of the van Hove singularity in the DOS. Thus, to achieve the high D(ε F ) using the bundle of nanotubes with single chirality, we should take into account the distance from each nanotube. In the case of double-walled carbon nanotubes, we find that the holes introduced to the inner tube by boron doping spread also on the outer tube, while the band structure of each tube remains almost unchanged.

Simulation on three dimensional bubble formation using MARS

International Nuclear Information System (INIS)

Kunugi, Tomoaki

1997-01-01

This paper describes a numerical simulation on three-dimensional bubble formation by means of the MARS (Multi-interfaces Advection and Reconstruction Solver) developed by the author. The comparison between two-dimensional and three-dimensional simulation on an agglomeration of two bubbles is discussed. Moreover, some simulation results regarding a phase change phenomena such as a boiling and condensation in a two dimensional enclosure with heated and cooled walls are presented. (author)

Asymmetric three-dimensional topography over mantle plumes.

Science.gov (United States)

Burov, Evgueni; Gerya, Taras

2014-09-04

The role of mantle-lithosphere interactions in shaping surface topography has long been debated. In general, it is supposed that mantle plumes and vertical mantle flows result in axisymmetric, long-wavelength topography, which strongly differs from the generally asymmetric short-wavelength topography created by intraplate tectonic forces. However, identification of mantle-induced topography is difficult, especially in the continents. It can be argued therefore that complex brittle-ductile rheology and stratification of the continental lithosphere result in short-wavelength modulation and localization of deformation induced by mantle flow. This deformation should also be affected by far-field stresses and, hence, interplay with the 'tectonic' topography (for example, in the 'active/passive' rifting scenario). Testing these ideas requires fully coupled three-dimensional numerical modelling of mantle-lithosphere interactions, which so far has not been possible owing to the conceptual and technical limitations of earlier approaches. Here we present new, ultra-high-resolution, three-dimensional numerical experiments on topography over mantle plumes, incorporating a weakly pre-stressed (ultra-slow spreading), rheologically realistic lithosphere. The results show complex surface evolution, which is very different from the smooth, radially symmetric patterns usually assumed as the canonical surface signature of mantle upwellings. In particular, the topography exhibits strongly asymmetric, small-scale, three-dimensional features, which include narrow and wide rifts, flexural flank uplifts and fault structures. This suggests a dominant role for continental rheological structure and intra-plate stresses in controlling dynamic topography, mantle-lithosphere interactions, and continental break-up processes above mantle plumes.

* Three-Dimensional Bioprinting of Polycaprolactone Reinforced Gene Activated Bioinks for Bone Tissue Engineering.

Science.gov (United States)

Cunniffe, Gráinne M; Gonzalez-Fernandez, Tomas; Daly, Andrew; Sathy, Binulal N; Jeon, Oju; Alsberg, Eben; Kelly, Daniel J

2017-09-01

Regeneration of complex bone defects remains a significant clinical challenge. Multi-tool biofabrication has permitted the combination of various biomaterials to create multifaceted composites with tailorable mechanical properties and spatially controlled biological function. In this study we sought to use bioprinting to engineer nonviral gene activated constructs reinforced by polymeric micro-filaments. A gene activated bioink was developed using RGD-γ-irradiated alginate and nano-hydroxyapatite (nHA) complexed to plasmid DNA (pDNA). This ink was combined with bone marrow-derived mesenchymal stem cells (MSCs) and then co-printed with a polycaprolactone supporting mesh to provide mechanical stability to the construct. Reporter genes were first used to demonstrate successful cell transfection using this system, with sustained expression of the transgene detected over 14 days postbioprinting. Delivery of a combination of therapeutic genes encoding for bone morphogenic protein and transforming growth factor promoted robust osteogenesis of encapsulated MSCs in vitro, with enhanced levels of matrix deposition and mineralization observed following the incorporation of therapeutic pDNA. Gene activated MSC-laden constructs were then implanted subcutaneously, directly postfabrication, and were found to support superior levels of vascularization and mineralization compared to cell-free controls. These results validate the use of a gene activated bioink to impart biological functionality to three-dimensional bioprinted constructs.

Role of active site rigidity in activity: MD simulation and fluorescence study on a lipase mutant.

Directory of Open Access Journals (Sweden)

Md Zahid Kamal

Full Text Available Relationship between stability and activity of enzymes is maintained by underlying conformational flexibility. In thermophilic enzymes, a decrease in flexibility causes low enzyme activity while in less stable proteins such as mesophiles and psychrophiles, an increase in flexibility is associated with enhanced enzyme activity. Recently, we identified a mutant of a lipase whose stability and activity were enhanced simultaneously. In this work, we probed the conformational dynamics of the mutant and the wild type lipase, particularly flexibility of their active site using molecular dynamic simulations and time-resolved fluorescence techniques. In contrast to the earlier observations, our data show that active site of the mutant is more rigid than wild type enzyme. Further investigation suggests that this lipase needs minimal reorganization/flexibility of active site residues during its catalytic cycle. Molecular dynamic simulations suggest that catalytically competent active site geometry of the mutant is relatively more preserved than wild type lipase, which might have led to its higher enzyme activity. Our study implies that widely accepted positive correlation between conformation flexibility and enzyme activity need not be stringent and draws attention to the possibility that high enzyme activity can still be accomplished in a rigid active site and stable protein structures. This finding has a significant implication towards better understanding of involvement of dynamic motions in enzyme catalysis and enzyme engineering through mutations in active site.

Three-dimensional tori and Arnold tongues

Energy Technology Data Exchange (ETDEWEB)

Sekikawa, Munehisa, E-mail: sekikawa@cc.utsunomiya-u.ac.jp [Department of Mechanical and Intelligent Engineering, Utsunomiya University, Utsunomiya-shi 321-8585 (Japan); Inaba, Naohiko [Organization for the Strategic Coordination of Research and Intellectual Property, Meiji University, Kawasaki-shi 214-8571 (Japan); Kamiyama, Kyohei [Department of Electronics and Bioinformatics, Meiji University, Kawasaki-shi 214-8571 (Japan); Aihara, Kazuyuki [Institute of Industrial Science, the University of Tokyo, Meguro-ku 153-8505 (Japan)

2014-03-15

This study analyzes an Arnold resonance web, which includes complicated quasi-periodic bifurcations, by conducting a Lyapunov analysis for a coupled delayed logistic map. The map can exhibit a two-dimensional invariant torus (IT), which corresponds to a three-dimensional torus in vector fields. Numerous one-dimensional invariant closed curves (ICCs), which correspond to two-dimensional tori in vector fields, exist in a very complicated but reasonable manner inside an IT-generating region. Periodic solutions emerge at the intersections of two different thin ICC-generating regions, which we call ICC-Arnold tongues, because all three independent-frequency components of the IT become rational at the intersections. Additionally, we observe a significant bifurcation structure where conventional Arnold tongues transit to ICC-Arnold tongues through a Neimark-Sacker bifurcation in the neighborhood of a quasi-periodic Hopf bifurcation (or a quasi-periodic Neimark-Sacker bifurcation) boundary.

New 3-D coordination polymers based on semi-rigid V-shape tetracarboxylates

International Nuclear Information System (INIS)

Huang, Jing-Jing; Xu, Wei; Wang, Yan-Ning; Yu, Jie-Hui; Zhang, Ping; Xu, Ji-Qing

2015-01-01

Under the hydrothermal conditions, the reactions of transition-metal salts, tetracarboxylic acids and N,N′-donor ligands yielded three new coordination polymers as [Cu 4 (fph) 2 (bpe) 3 (H 2 O) 2 ]·2H 2 O (fph=4,4′-(hexafluoroisopropylidene)diphthalate, bpe=1,2-bis(pyridyl)ethylene) 1, [Co 2 (fph)(bpa) 2 (H 2 O) 2 ]·3H 2 O (bpa=1,2-bis(pyridyl)ethylane) 2, and [Ni(H 2 O)(H 2 oph)(bpa)] (oph=4,4′-oxydiphthalate) 3. X-ray single-crystal diffraction analysis revealed that the title three compounds all possess the three-dimensional (3-D) network structures. For compound 1, the fph molecules first link the Cu 2+ ions into a two-dimensional (2-D) wave-like layer with a (4,4) topology. The bpe molecules act as the second linkers, extending the 2-D layers into a 3-D network. For compound 2, the fph molecules still serve as the first connectors, linking the Co 2+ ions into a one-dimensional (1-D) tube-like chain. Then the bpa molecules propagate the chains into a 3-D (4,4,4)-connected network. In the formation of the 3-D network of compound 3, the oph molecule does not play a role. The bpa molecules as well as the water molecules act as a mixed bridge. Only a kind of 4-connected metal node is observed in compound 3. The magnetic properties of compounds 1–3 were investigated and all exhibit the predominant antiferromegnetic magnetic behaviors. - Graphical abstract: Structures of three semi-rigid V-shape tetracarboxylate-based coordination polymers were reported, and their magnetic properties were investigated. - Highlights: • Structures of three tetracarboxylate-based coordination polymers were reported. • Role of organic bases in metal–tetracarboxylate compounds was discussed. • Characters of V-shape and semi-rigidity for tetracarboxylate play a key role in crystal growth. • Their magnetic properties were investigated

New 3-D coordination polymers based on semi-rigid V-shape tetracarboxylates

Energy Technology Data Exchange (ETDEWEB)

Huang, Jing-Jing; Xu, Wei; Wang, Yan-Ning [College of Chemistry, Jilin University, Jiefang Road 2519, Changchun 130023, Jilin (China); State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, Jilin University, Qianjin Road 2699, Changchun 130012, Jilin (China); Yu, Jie-Hui, E-mail: jhyu@jlu.edu.cn [College of Chemistry, Jilin University, Jiefang Road 2519, Changchun 130023, Jilin (China); State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, Jilin University, Qianjin Road 2699, Changchun 130012, Jilin (China); Zhang, Ping, E-mail: zhangping@jlu.edu.cn [College of Chemistry, Jilin University, Jiefang Road 2519, Changchun 130023, Jilin (China); Xu, Ji-Qing [College of Chemistry, Jilin University, Jiefang Road 2519, Changchun 130023, Jilin (China); State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, Jilin University, Qianjin Road 2699, Changchun 130012, Jilin (China)

2015-03-15

Under the hydrothermal conditions, the reactions of transition-metal salts, tetracarboxylic acids and N,N′-donor ligands yielded three new coordination polymers as [Cu{sub 4}(fph){sub 2}(bpe){sub 3}(H{sub 2}O){sub 2}]·2H{sub 2}O (fph=4,4′-(hexafluoroisopropylidene)diphthalate, bpe=1,2-bis(pyridyl)ethylene) 1, [Co{sub 2}(fph)(bpa){sub 2}(H{sub 2}O){sub 2}]·3H{sub 2}O (bpa=1,2-bis(pyridyl)ethylane) 2, and [Ni(H{sub 2}O)(H{sub 2}oph)(bpa)] (oph=4,4′-oxydiphthalate) 3. X-ray single-crystal diffraction analysis revealed that the title three compounds all possess the three-dimensional (3-D) network structures. For compound 1, the fph molecules first link the Cu{sup 2+} ions into a two-dimensional (2-D) wave-like layer with a (4,4) topology. The bpe molecules act as the second linkers, extending the 2-D layers into a 3-D network. For compound 2, the fph molecules still serve as the first connectors, linking the Co{sup 2+} ions into a one-dimensional (1-D) tube-like chain. Then the bpa molecules propagate the chains into a 3-D (4,4,4)-connected network. In the formation of the 3-D network of compound 3, the oph molecule does not play a role. The bpa molecules as well as the water molecules act as a mixed bridge. Only a kind of 4-connected metal node is observed in compound 3. The magnetic properties of compounds 1–3 were investigated and all exhibit the predominant antiferromegnetic magnetic behaviors. - Graphical abstract: Structures of three semi-rigid V-shape tetracarboxylate-based coordination polymers were reported, and their magnetic properties were investigated. - Highlights: • Structures of three tetracarboxylate-based coordination polymers were reported. • Role of organic bases in metal–tetracarboxylate compounds was discussed. • Characters of V-shape and semi-rigidity for tetracarboxylate play a key role in crystal growth. • Their magnetic properties were investigated.

Dynamical analysis of an orbiting three-rigid-body system

Energy Technology Data Exchange (ETDEWEB)

Pagnozzi, Daniele, E-mail: daniele.pagnozzi@strath.ac.uk, E-mail: james.biggs@strath.ac.uk; Biggs, James D., E-mail: daniele.pagnozzi@strath.ac.uk, E-mail: james.biggs@strath.ac.uk [Department of Mechanical and Aerospace Engineering, University of Strathclyde, Glasgow, Scotland (United Kingdom)

2014-12-10

The development of multi-joint-spacecraft mission concepts calls for a deeper understanding of their nonlinear dynamics to inform and enhance system design. This paper presents a study of a three-finite-shape rigid-body system under the action of an ideal central gravitational field. The aim of this paper is to gain an insight into the natural dynamics of this system. The Hamiltonian dynamics is derived and used to identify relative attitude equilibria of the system with respect to the orbital reference frame. Then a numerical investigation of the behaviour far from the equilibria is provided using tools from modern dynamical systems theory such as energy methods, phase portraits and Poincarè maps. Results reveal a complex structure of the dynamics as well as the existence of connections between some of the equilibria. Stable equilibrium configurations appear to be surrounded by very narrow regions of regular and quasi-regular motions. Trajectories evolve on chaotic motions in the rest of the domain.

Dynamics of pre-strained bi-material elastic systems linearized three-dimensional approach

CERN Document Server

Akbarov, Surkay D

2015-01-01

This book deals with dynamics of pre-stressed or pre-strained bi-material elastic systems consisting of stack of pre-stressed layers, stack of pre-stressed layers and pre-stressed half space (or half plane), stack of pre-stressed layers as well as absolute rigid foundation, pre-stressed compound solid and hollow cylinders and pre-stressed sandwich hollow cylinders. The problems considered in the book relate to the dynamics of a moving and oscillating moving load, forced vibration caused by linearly located or point located time-harmonic forces acting to the foregoing systems. Moreover, a considerable part of the book relate to the problems regarding the near surface, torsional and axisymmetric longitudinal waves propagation and dispersion in the noted above bi-material elastic systems. The book carries out the investigations within the framework of the piecewise homogeneous body model with the use of the Three-Dimensional Linearized Theory of Elastic Waves in Initially Stressed Bodies.

Three Dimensional Response Spectrum Soil Structure Modeling Versus Conceptual Understanding To Illustrate Seismic Response Of Structures

International Nuclear Information System (INIS)

Touqan, Abdul Razzaq

2008-01-01

Present methods of analysis and mathematical modeling contain so many assumptions that separate them from reality and thus represent a defect in design which makes it difficult to analyze reasons of failure. Three dimensional (3D) modeling is so superior to 1D or 2D modeling, static analysis deviates from the true nature of earthquake load which is ''a dynamic punch'', and conflicting assumptions exist between structural engineers (who assume flexible structures on rigid block foundations) and geotechnical engineers (who assume flexible foundations supporting rigid structures). Thus a 3D dynamic soil-structure interaction is a step that removes many of the assumptions and thus clears reality to a greater extent. However such a model cannot be analytically analyzed. We need to anatomize and analogize it. The paper will represent a conceptual (analogical) 1D model for soil structure interaction and clarifies it by comparing its outcome with 3D dynamic soil-structure finite element analysis of two structures. The aim is to focus on how to calculate the period of the structure and to investigate effect of variation of stiffness on soil-structure interaction

Active feedback wide-field optical low-coherence interferometry for ultrahigh-speed three-dimensional morphometry

International Nuclear Information System (INIS)

Choi, Woo June; Choi, Hae Young; Lee, Byeong Ha; Na, Jihoon; Eom, Jonghyun

2010-01-01

A novel optical interferometric scheme for ultrahigh-speed three-dimensional morphometry is proposed. The system is based on wide-field optical coherence tomography (WF-OCT) but with optically chopped illumination. The chopping frequency is feedback-controlled to be always matched with the Doppler frequency of the OCT interferometer, which provides an efficient page-wide demodulation suitable for ultrahigh-speed volumetric imaging. To compensate the unwanted variation in the OCT Doppler frequency of the system, the illumination frequency is phase-locked with an auxiliary laser interferometer which shares the reference arm with the OCT interferometer. The two-dimensional (2D) interference signals projected on the 2D array pixels of a 200 Hz CCD are accumulated during one imaging frame of the CCD. Then, each pixel of the CCD demodulates the OCT signal automatically. Owing to the proposed active frequency-locked illumination scheme, the demodulation does not depend on the variation in the axial scanning speed. Volumetric topograms or/and tomograms of several samples were achieved and rendered with a sensitivity of 58 dB at an axial scan speed of 0.805 mm s −1

Three-dimensional time-lapse velocity tomography of an underground longwall panel

Energy Technology Data Exchange (ETDEWEB)

Luxbacher, K.; Westman, E.; Swanson, P.; Karfakis, M. [Virginia Tech., Blacksburg, VA (United States). Dept. of Mining & Minerals Engineering

2008-06-15

Three-dimensional velocity tomograms were generated to image the stress redistribution around an underground coal longwall panel to produce a better understanding of the mechanisms that lead to ground failure, especially rockbursts. Mining-induced microseismic events provided passive sources for the three-dimensional velocity tomography. Surface-mounted geophones monitored microseismic activity for 18 days. Eighteen tomograms were generated and high-velocity regions correlated with high abutment stresses predicted by numerical modeling. Additionally, the high-velocity regions were observed to redistribute as the longwall face retreated, indicating that velocity tomography may be an appropriate technology for monitoring stress redistribution in underground mines.

Three-dimensional CT of the pediatric spine

International Nuclear Information System (INIS)

Starshak, R.J.; Crawford, C.R.; Waisman, R.C.; Sty, J.R.

1987-01-01

CT of the spine has been shown to be useful in evaluating congenital, neoplastic, inflammatory, and traumatic lesions. Any portion of the neural arch may be involved by these disease processes. However, the complex nature of the spinal column can make evaluation of these abnormalities difficult on axial CT. This is especially true if the spine is distorted by scoliosis, kyphosis, or lordosis. The principal advantage of three-dimensional CT is its ability to display the surface relationships of complicated objects. The complexity of the spinal axis makes it ideal for study with three-dimensional CT. This presentation illustrates the advantages and drawbacks of three-dimensional CT in spinal abnormalities in children

The Effect of Three-Dimensional Simulations on the Understanding of Chemical Structures and Their Properties

Science.gov (United States)

Urhahne, Detlef; Nick, Sabine; Schanze, Sascha

2009-08-01

In a series of three experimental studies, the effectiveness of three-dimensional computer simulations to aid the understanding of chemical structures and their properties was investigated. Arguments for the usefulness of three-dimensional simulations were derived from Mayer’s generative theory of multimedia learning. Simulations might lead to a decrease in cognitive load and thus support active learning. In our studies, the learning effectiveness of three-dimensional simulations was compared to two-dimensional illustrations by use of different versions of a computer programme concerning the modifications of carbon. The first and third study with freshman students of chemistry and biochemistry show that no more knowledge was acquired when participants learnt with three-dimensional simulations than with two-dimensional figures. In the second study with 16-year old secondary school students, use of simulations facilitated the acquisition of conceptual knowledge. It was concluded that three-dimensional simulations are more effective for younger students who lack the experience of learning with different visual representation formats in chemistry. In all three studies, a significant relationship between spatial ability and conceptual knowledge about the modifications of carbon was detected.

Three-dimensional display of magnetic source imaging (MSI)

International Nuclear Information System (INIS)

Morioka, Takato; Yamamoto, Tomoya; Nishio, Shunji; Hasuo, Kanehiro; Fujii, Kiyotaka; Fukui, Masashi; Nitta, Koichi.

1995-01-01

Magnetic source imaging (MSI) is a relatively new, noninvasive technique for defining the relationship between brain structure and function of individual patients, and to establish comparisons from one patient to another. This is achieved by combining detailed neurophysiological data derived via magnetoencephalography (MEG) with neuroimaging data such as computed tomographic scan and magnetic resonance imaging (MRI). The noninvasive presurgical mapping of cortical functional somatosensory activity and the direct mapping of epilepsy-associated activity are among the neurosurgical uses that are emerging for MSI. Although the procedure provides clinically useful data, there are still limitations to two-dimensional MSI. We employ three-dimensional (3-D) MSI, superimposing MSI localizations on 3-D volumetric reconstruction of MRI. 3-D MSI enhances the visualization of the entire sensory homunculus and clearly demonstrates the spatial relationship with structural lesions. The functional localization of the epileptic focus in spatial relation to the lesion provides important clues for preoperative planning and on the epileptogenicity of the lesion. 3-D MSI improves localization of the sensory cortex and generator areas of epileptic activity. (author)

Electrochemical in situ regeneration of granular activated carbon using a three-dimensional reactor.

Science.gov (United States)

Sun, Hong; Liu, Zhigang; Wang, Ying; Li, Yansheng

2013-12-01

Electrochemical in situ regeneration of granular activated carbon (GAC) saturated with phenol was experimentally investigated using a three-dimensional electrode reactor with titanium filter electrode arrays. The feasibility of the electrochemical regeneration has been assessed by monitoring the regeneration efficiency and chemical oxygen demand (COD). The influence of the applied current, the effluent flow rate, and the effluent path of the electrochemical cell have been systematically studied. Under the optimum conditions, the regeneration efficiency of GAC could reach 94% in 2 hr, and no significant declination was observed after five-time continuous adsorption-regeneration cycles. The adsorption of organic pollutants was almost completely mineralized due to electrochemical oxidation, indicating that this regeneration process is much more potentially cost-effective for application. Copyright © 2013 The Research Centre for Eco-Environmental Sciences, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.

Three-dimensional deformation of orthodontic brackets

Science.gov (United States)

Melenka, Garrett W; Nobes, David S; Major, Paul W

2013-01-01

Braces are used by orthodontists to correct the misalignment of teeth in the mouth. Archwire rotation is a particular procedure used to correct tooth inclination. Wire rotation can result in deformation to the orthodontic brackets, and an orthodontic torque simulator has been designed to examine this wire–bracket interaction. An optical technique has been employed to measure the deformation due to size and geometric constraints of the orthodontic brackets. Images of orthodontic brackets are collected using a stereo microscope and two charge-coupled device cameras, and deformation of orthodontic brackets is measured using a three-dimensional digital image correlation technique. The three-dimensional deformation of orthodontic brackets will be evaluated. The repeatability of the three-dimensional digital image correlation measurement method was evaluated by performing 30 archwire rotation tests using the same bracket and archwire. Finally, five Damon 3MX and five In-Ovation R self-ligating brackets will be compared using this technique to demonstrate the effect of archwire rotation on bracket design. PMID:23762201

Three-dimensional deformation of orthodontic brackets.

Science.gov (United States)

Melenka, Garrett W; Nobes, David S; Major, Paul W; Carey, Jason P

2013-01-01

Braces are used by orthodontists to correct the misalignment of teeth in the mouth. Archwire rotation is a particular procedure used to correct tooth inclination. Wire rotation can result in deformation to the orthodontic brackets, and an orthodontic torque simulator has been designed to examine this wire-bracket interaction. An optical technique has been employed to measure the deformation due to size and geometric constraints of the orthodontic brackets. Images of orthodontic brackets are collected using a stereo microscope and two charge-coupled device cameras, and deformation of orthodontic brackets is measured using a three-dimensional digital image correlation technique. The three-dimensional deformation of orthodontic brackets will be evaluated. The repeatability of the three-dimensional digital image correlation measurement method was evaluated by performing 30 archwire rotation tests using the same bracket and archwire. Finally, five Damon 3MX and five In-Ovation R self-ligating brackets will be compared using this technique to demonstrate the effect of archwire rotation on bracket design.

Three-dimensional plasma equilibrium near a separatrix

International Nuclear Information System (INIS)

Reiman, A.H.; Pomphrey, N.; Boozer, A.H.

1988-08-01

The limiting behavior of a general three-dimensional MHD equilibrium near a separatrix is calculated explicitly. No expansions in β or assumptions about island widths are made. Implications of the results for the numerical calculation of such equilibria, are discussed, as well as for issues concerning the existence of three-dimensional MHD equilibria. 16 refs., 2 figs

Advancing three-dimensional MEMS by complimentary laser micro manufacturing

Science.gov (United States)

Palmer, Jeremy A.; Williams, John D.; Lemp, Tom; Lehecka, Tom M.; Medina, Francisco; Wicker, Ryan B.

2006-01-01

This paper describes improvements that enable engineers to create three-dimensional MEMS in a variety of materials. It also provides a means for selectively adding three-dimensional, high aspect ratio features to pre-existing PMMA micro molds for subsequent LIGA processing. This complimentary method involves in situ construction of three-dimensional micro molds in a stand-alone configuration or directly adjacent to features formed by x-ray lithography. Three-dimensional micro molds are created by micro stereolithography (MSL), an additive rapid prototyping technology. Alternatively, three-dimensional features may be added by direct femtosecond laser micro machining. Parameters for optimal femtosecond laser micro machining of PMMA at 800 nanometers are presented. The technical discussion also includes strategies for enhancements in the context of material selection and post-process surface finish. This approach may lead to practical, cost-effective 3-D MEMS with the surface finish and throughput advantages of x-ray lithography. Accurate three-dimensional metal microstructures are demonstrated. Challenges remain in process planning for micro stereolithography and development of buried features following femtosecond laser micro machining.

On two-dimensionalization of three-dimensional turbulence in shell models

DEFF Research Database (Denmark)

Chakraborty, Sagar; Jensen, Mogens Høgh; Sarkar, A.

2010-01-01

Applying a modified version of the Gledzer-Ohkitani-Yamada (GOY) shell model, the signatures of so-called two-dimensionalization effect of three-dimensional incompressible, homogeneous, isotropic fully developed unforced turbulence have been studied and reproduced. Within the framework of shell m......-similar PDFs for longitudinal velocity differences are also presented for the rotating 3D turbulence case....

Leadership and organizational ethics: the three dimensional African perspectives.

Science.gov (United States)

Mathooko, Jude Mutuku

2013-01-01

This paper addresses the past, present and future aspects of African leadership and organizational ethics that have, are and will be key for any organization to sustain its systems and structures. Organizational ethics revolves around written and/or unwritten guidelines, ethical values, principles, rules and standards, that are drawn from the harmonious coexistence with the biosphere and it is how these elements are applied that dictates the style of leadership and the ethical thinking of the leaders. Africa has a wide range of complexities which are compounded by, inter alia, tribal divisiveness, selfish leadership, wealth inequality, and massive unemployment. Africans tend to draw their leadership and ethical practices and reflections from the events in the environment with which they have interacted for many years. However, in order to fully address and understand the African perspective in leadership and organizational ethics, a broad comprehension of the African diverse and complex landscape is needed through unravelling of the three dimensional existence of the people. African ethics, developed over time, unifies organizations and leadership since it is part of life and is practised, sub-consciously or unconsciously, by the people as they transform from one practice to the other, and during intergenerational transitions. Globalization, liberalization, technological changes and advancement, and market changes are rapidly transforming the environment in which organizations operate. In such a situation, an effective and true leader cannot be rigid but should be flexible, with the ability to use different leadership styles whenever the situation calls for it. Only those leaders with a three-dimensional perspective live inspiring lives, live with a cause and adopt organizational ethics and leadership styles that will stand the test of time. Despite Africa being the cradle of humankind, leadership and organizational ethics is still in its infancy and wanting, even

THREE-DIMENSIONAL WEB-BASED PHYSICS SIMULATION APPLICATION FOR PHYSICS LEARNING TOOL

Directory of Open Access Journals (Sweden)

William Salim

2012-10-01

Full Text Available The purpose of this research is to present a multimedia application for doing simulation in Physics. The application is a web based simulator that implementing HTML5, WebGL, and JavaScript. The objects and the environment will be in three dimensional views. This application is hoped will become the substitute for practicum activity. The current development is the application only covers Newtonian mechanics. Questionnaire and literature study is used as the data collecting method. While Waterfall Method used as the design method. The result is Three-DimensionalPhysics Simulator as online web application. Three-Dimensionaldesign and mentor-mentee relationship is the key features of this application. The conclusion made is Three-DimensionalPhysics Simulator already fulfilled in both design and functionality according to user. This application also helps them to understand Newtonian mechanics by simulation. Improvements are needed, because this application only covers Newtonian Mechanics. There is a lot possibility in the future that this simulation can also covers other Physics topic, such as optic, energy, or electricity.Keywords: Simulation, Physic, Learning Tool, HTML5, WebGL

Synthesis of three-dimensionally ordered macro-/mesoporous Pt with high electrocatalytic activity by a dual-templating approach

Science.gov (United States)

Zhang, Chengwei; Yang, Hui; Sun, Tingting; Shan, Nannan; Chen, Jianfeng; Xu, Lianbin; Yan, Yushan

2014-01-01

Three dimensionally ordered macro-/mesoporous (3DOM/m) Pt catalysts are fabricated by chemical reduction employing a dual-templating synthesis approach combining both colloidal crystal (opal) templating (hard-templating) and lyotropic liquid crystal templating (soft-templating) techniques. The macropore walls of the prepared 3DOM/m Pt exhibit a uniform mesoporous structure composed of polycrystalline Pt nanoparticles. Both the size of the mesopores and Pt nanocrystallites are in the range of 3-5 nm. The 3DOM/m Pt catalyst shows a larger electrochemically active surface area (ECSA), and higher catalytic activity as well as better poisoning tolerance for methanol oxidation reaction (MOR) than the commercial Pt black catalyst.

Computational study of three-dimensional wake structure

International Nuclear Information System (INIS)

Himeno, R.; Shirayama, S.; Kamo, K.; Kuwahara, K.

1986-01-01

Three-dimensional wake structure is studied by numerically solving the incompressible Navier-Stokes equations. Results are visualized by a three-dimensional color graphic system. It was found that a pair of vortex tubes separated from a body plays the most important role in the wake. Near the body vortex tubes are rather stable, however, they gradually become unsteady as they flow down

Standalone visualization tool for three-dimensional DRAGON geometrical models

International Nuclear Information System (INIS)

Lukomski, A.; McIntee, B.; Moule, D.; Nichita, E.

2008-01-01

DRAGON is a neutron transport and depletion code able to solve one-, two- and three-dimensional problems. To date DRAGON provides two visualization modules, able to represent respectively two- and three-dimensional geometries. The two-dimensional visualization module generates a postscript file, while the three dimensional visualization module generates a MATLAB M-file with instructions for drawing the tracks in the DRAGON TRACKING data structure, which implicitly provide a representation of the geometry. The current work introduces a new, standalone, tool based on the open-source Visualization Toolkit (VTK) software package which allows the visualization of three-dimensional geometrical models by reading the DRAGON GEOMETRY data structure and generating an axonometric image which can be manipulated interactively by the user. (author)

SNAP - a three dimensional neutron diffusion code

International Nuclear Information System (INIS)

McCallien, C.W.J.

1993-02-01

This report describes a one- two- three-dimensional multi-group diffusion code, SNAP, which is primarily intended for neutron diffusion calculations but can also carry out gamma calculations if the diffusion approximation is accurate enough. It is suitable for fast and thermal reactor core calculations and for shield calculations. SNAP can solve the multi-group neutron diffusion equations using finite difference methods. The one-dimensional slab, cylindrical and spherical geometries and the two-dimensional case are all treated as simple special cases of three-dimensional geometries. Numerous reflective and periodic symmetry options are available and may be used to reduce the number of mesh points necessary to represent the system. Extrapolation lengths can be specified at internal and external boundaries. (Author)

Three-dimensional fluorescence lifetime tomography

International Nuclear Information System (INIS)

Godavarty, Anuradha; Sevick-Muraca, Eva M.; Eppstein, Margaret J.

2005-01-01

Near-infrared fluorescence tomography using molecularly targeted lifetime-sensitive, fluorescent contrast agents have applications for early-stage cancer diagnostics. Yet, although the measurement of fluorescent lifetime imaging microscopy (FLIM) is extensively used in microscopy and spectroscopy applications, demonstration of fluorescence lifetime tomography for medical imaging is limited to two-dimensional studies. Herein, the feasibility of three-dimensional fluorescence-lifetime tomography on clinically relevant phantom volumes is established, using (i) a gain-modulated intensified charge coupled device (CCD) and modulated laser diode imaging system, (ii) two fluorescent contrast agents, e.g., Indocyanine green and 3-3'-Diethylthiatricarbocyanine iodide differing in their fluorescence lifetime by 0.62 ns, and (iii) a two stage approximate extended Kalman filter reconstruction algorithm. Fluorescence measurements of phase and amplitude were acquired on the phantom surface under different target to background fluorescence absorption (70:1, 100:1) and fluorescence lifetime (1:1, 2.1:1) contrasts at target depths of 1.4-2 cm. The Bayesian tomography algorithm was employed to obtain three-dimensional images of lifetime and absorption owing to the fluorophores

Self-consistent theory of three-dimensional convection in the geomagnetic tail

International Nuclear Information System (INIS)

Birn, J.; Schindler, K.

1983-01-01

The self-consistent theory of time-dependent convection in the earth's magnetotail of Schindler and Birn (1982) is extended to three dimensions to include more realistic tail geometry and three-dimensional flow. We confirm that a steady state solution implies unrealistic tail geometry or large particle or energy losses that are unrealistic during quiet times and conclude therefore that as in the 2-dimensional case the magnetotail becomes time-dependent for typical convection electric fields. Explicit solutions are derived, even analytically, for the three-dimensional flow and the electric and magnetic field in a realistic tail geometry, and quantitative examples are presented. Consequences of time-dependent convection are demonstrated considering two idealized cases of magnetosphere response to solar wind changes: (1) uniform compression as the likely consequence of increasing (static, dynamic or magnetic) solar wind pressure; and (2) compression only in the z direction perpendicular to the plasma sheet as the probable consequence of a dawn to dusk external electric field (E/sub y/>0), corresponding to a southward interplanetary magnetic field component (B/sub z/ 0 with geomagnetic activity. Several other features, already present in the 2-dimensional theory, are confirmed

Development of three dimensional solid modeler

International Nuclear Information System (INIS)

Zahoor, R.M.A.

1999-01-01

The work presented in this thesis is aimed at developing a three dimensional solid modeler employing computer graphics techniques using C-Language. Primitives have been generated, by combination of plane surfaces, for various basic geometrical shapes including cylinder, cube and cone. Back face removal technique for hidden surface removal has also been incorporated. Various transformation techniques such as scaling, translation, and rotation have been included for the object animation. Three dimensional solid modeler has been created by the union of two primitives to demonstrate the capabilities of the developed program. (author)

Polycrystalline diamond detectors with three-dimensional electrodes

Energy Technology Data Exchange (ETDEWEB)

Lagomarsino, S., E-mail: lagomarsino@fi.infn.it [University of Florence, Department of Physics, Via Sansone 1, 50019 Sesto Fiorentino (Italy); INFN Firenze, Via B. Rossi 1, 50019 Sesto Fiorentino (Italy); Bellini, M. [INO-CNR Firenze, Largo E. Fermi 6, 50125 Firenze (Italy); Brianzi, M. [INFN Firenze, Via B. Rossi 1, 50019 Sesto Fiorentino (Italy); Carzino, R. [Smart Materials-Nanophysics, Istituto Italiano di Tecnologia, Genova, Via Morego 30, 16163 Genova (Italy); Cindro, V. [Joseph Stefan Institute, Jamova Cesta 39, 1000 Ljubljana (Slovenia); Corsi, C. [University of Florence, Department of Physics, Via Sansone 1, 50019 Sesto Fiorentino (Italy); LENS Firenze, Via N. Carrara 1, 50019 Sesto Fiorentino (Italy); Morozzi, A.; Passeri, D. [INFN Perugia, Perugia (Italy); Università degli Studi di Perugia, Dipartimento di Ingegneria, via G. Duranti 93, 06125 Perugia (Italy); Sciortino, S. [University of Florence, Department of Physics, Via Sansone 1, 50019 Sesto Fiorentino (Italy); INFN Firenze, Via B. Rossi 1, 50019 Sesto Fiorentino (Italy); Servoli, L. [INFN Perugia, Perugia (Italy)

2015-10-01

The three-dimensional concept in diamond detectors has been applied, so far, to high quality single-crystal material, in order to test this technology in the best available conditions. However, its application to polycrystalline chemical vapor deposited diamond could be desirable for two reasons: first, the short inter-electrode distance of three-dimensional detectors should improve the intrinsically lower collection efficiency of polycrystalline diamond, and second, at high levels of radiation damage the performances of the poly-crystal material are not expected to be much lower than those of the single crystal one. We report on the fabrication and test of three-dimensional polycrystalline diamond detectors with several inter-electrode distances, and we demonstrate that their collection efficiency is equal or higher than that obtained with conventional planar detectors fabricated with the same material. - Highlights: • Pulsed laser fabrication of polycristalline diamond detectors with 3D electrodes. • Measurement of the charge collection efficiency (CCE) under beta irradiation. • Comparation between the CCE of 3D and conventional planar diamond sensors. • A rationale for the behavior of three-dimensional and planar sensors is given.

Three-dimensional Ca2+ imaging advances understanding of astrocyte biology.

Science.gov (United States)

Bindocci, Erika; Savtchouk, Iaroslav; Liaudet, Nicolas; Becker, Denise; Carriero, Giovanni; Volterra, Andrea

2017-05-19

Astrocyte communication is typically studied by two-dimensional calcium ion (Ca 2+ ) imaging, but this method has not yielded conclusive data on the role of astrocytes in synaptic and vascular function. We developed a three-dimensional two-photon imaging approach and studied Ca 2+ dynamics in entire astrocyte volumes, including during axon-astrocyte interactions. In both awake mice and brain slices, we found that Ca 2+ activity in an individual astrocyte is scattered throughout the cell, largely compartmented between regions, preponderantly local within regions, and heterogeneously distributed regionally and locally. Processes and endfeet displayed frequent fast activity, whereas the soma was infrequently active. In awake mice, activity was higher than in brain slices, particularly in endfeet and processes, and displayed occasional multifocal cellwide events. Astrocytes responded locally to minimal axonal firing with time-correlated Ca 2+ spots. Copyright © 2017, American Association for the Advancement of Science.

Three-dimensional local ALE-FEM method for fluid flow in domains containing moving boundaries/objects interfaces

Energy Technology Data Exchange (ETDEWEB)

Carrington, David Bradley [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States); Monayem, A. K. M. [Univ. of New Mexico, Albuquerque, NM (United States); Mazumder, H. [Univ. of New Mexico, Albuquerque, NM (United States); Heinrich, Juan C. [Univ. of New Mexico, Albuquerque, NM (United States)

2015-03-05

A three-dimensional finite element method for the numerical simulations of fluid flow in domains containing moving rigid objects or boundaries is developed. The method falls into the general category of Arbitrary Lagrangian Eulerian methods; it is based on a fixed mesh that is locally adapted in the immediate vicinity of the moving interfaces and reverts to its original shape once the moving interfaces go past the elements. The moving interfaces are defined by separate sets of marker points so that the global mesh is independent of interface movement and the possibility of mesh entanglement is eliminated. The results is a fully robust formulation capable of calculating on domains of complex geometry with moving boundaries or devises that can also have a complex geometry without danger of the mesh becoming unsuitable due to its continuous deformation thus eliminating the need for repeated re-meshing and interpolation. Moreover, the boundary conditions on the interfaces are imposed exactly. This work is intended to support the internal combustion engines simulator KIVA developed at Los Alamos National Laboratories. The model's capabilities are illustrated through application to incompressible flows in different geometrical settings that show the robustness and flexibility of the technique to perform simulations involving moving boundaries in a three-dimensional domain.

Three dimensional diffusion calculations of nuclear reactors

International Nuclear Information System (INIS)

Caspo, N.

1981-07-01

This work deals with the three dimensional calculation of nuclear reactors using the code TRITON. The purposes of the work were to perform three-dimensional computations of the core of the Soreq nuclear reactor and of the power reactor ZION and to validate the TRITON code. Possible applications of the TRITON code in Soreq reactor calculations and in power reactor research are suggested. (H.K.)

Study of three-dimensional image display by systemic CT

International Nuclear Information System (INIS)

Fujioka, Tadao; Ebihara, Yoshiyuki; Unei, Hiroshi; Hayashi, Masao; Shinohe, Tooru; Wada, Yuji; Sakai, Takatsugu; Kashima, Kenji; Fujita, Yoshihiro

1989-01-01

A head phantom for CT was scanned at 2 mm intervals from the cervix to the vertex in an attempt to obtain a three-dimensional image display of bones and facial epidermis from an ordinary axial image. Clinically, three-dimensional images were formed at eye sockets and hip joints. With the three-dimensional image using the head phantom, the entire head could be displayed at any angle. Clinically, images were obtained that could not be attained by ordinary CT scanning, such as broken bones in eye sockets and stereoscopic structure at the bottom of a cranium. The three-dimensional image display is considered to be useful in clinical diagnosis. (author)

Continuum modeling of three-dimensional truss-like space structures

Science.gov (United States)

Nayfeh, A. H.; Hefzy, M. S.

1978-01-01

A mathematical and computational analysis capability has been developed for calculating the effective mechanical properties of three-dimensional periodic truss-like structures. Two models are studied in detail. The first, called the octetruss model, is a three-dimensional extension of a two-dimensional model, and the second is a cubic model. Symmetry considerations are employed as a first step to show that the specific octetruss model has four independent constants and that the cubic model has two. The actual values of these constants are determined by averaging the contributions of each rod element to the overall structure stiffness. The individual rod member contribution to the overall stiffness is obtained by a three-dimensional coordinate transformation. The analysis shows that the effective three-dimensional elastic properties of both models are relatively close to each other.

Birationally rigid varieties. I. Fano varieties

International Nuclear Information System (INIS)

Pukhlikov, A V

2007-01-01

The theory of birational rigidity of rationally connected varieties generalises the classical rationality problem. This paper gives a survey of the current state of this theory and traces its history from Noether's theorem and the Lueroth problem to the latest results on the birational superrigidity of higher-dimensional Fano varieties. The main components of the method of maximal singularities are considered.

Three-dimensional simulations of resistance spot welding

DEFF Research Database (Denmark)

Nielsen, Chris Valentin; Zhang, Wenqi; Perret, William

2014-01-01

This paper draws from the fundamentals of electro-thermo-mechanical coupling to the main aspects of finite element implementation and three-dimensional modelling of resistance welding. A new simulation environment is proposed in order to perform three-dimensional simulations and optimization...... of resistance welding together with the simulations of conventional and special-purpose quasi-static mechanical tests. Three-dimensional simulations of resistance welding consider the electrical, thermal, mechanical and metallurgical characteristics of the material as well as the operating conditions...... of the welding machines. Simulations of the mechanical tests take into account material softening due to the accumulation of ductile damage and cover conventional tests, such as tensile–shear tests, cross-tension test and peel tests, as well as the possibility of special-purpose tests designed by the users...

[Three-dimensional display simulation of lung surgery using "active shutter glasses"].

Science.gov (United States)

Onuki, Takamasa; Kanzaki, Masato; Sakamoto, Kei; Kikkawa, Takuma; Isaka, Tamami; Shimizu, Toshihide; Oyama, Kunihiro; Murasugi, Masahide

2011-08-01

We have reported preoperative 3-dimensional (3D) simulation of thoracoscopic lung surgery using self-made software and internet shareware of 3D-modeler. Using "active shutter glasses", we have tried the "3D display simulation" of lung surgery. 3D display was more effective to grasp clear 3D interrelation between the bronchii and pulmonary vascular system than those in images of currently in use with the same information volume.

Depth-enhanced three-dimensional-two-dimensional convertible display based on modified integral imaging.

Science.gov (United States)

Park, Jae-Hyeung; Kim, Hak-Rin; Kim, Yunhee; Kim, Joohwan; Hong, Jisoo; Lee, Sin-Doo; Lee, Byoungho

2004-12-01

A depth-enhanced three-dimensional-two-dimensional convertible display that uses a polymer-dispersed liquid crystal based on the principle of integral imaging is proposed. In the proposed method, a lens array is located behind a transmission-type display panel to form an array of point-light sources, and a polymer-dispersed liquid crystal is electrically controlled to pass or to scatter light coming from these point-light sources. Therefore, three-dimensional-two-dimensional conversion is accomplished electrically without any mechanical movement. Moreover, the nonimaging structure of the proposed method increases the expressible depth range considerably. We explain the method of operation and present experimental results.

An algorithm for three-dimensional imaging in the positron camera

International Nuclear Information System (INIS)

Chen Kun; Ma Mei; Xu Rongfen; Shen Miaohe

1986-01-01

A mathematical algorithm of back-projection filtered for image reconstructions using two-dimensional signals detected from parallel multiwire proportional chambers is described. The approaches of pseudo three-dimensional and full three-dimensional image reconstructions are introduced, and the available point response functions are defined as well. The designing parameters and computation procedure of the full three-dimensional method is presented

Selective three-dimensional hydrophilization of microstructured polymer surfaces through confined photocatalytic oxidation

International Nuclear Information System (INIS)

Ammosova, Lena; Jiang, Yu; Suvanto, Mika; Pakkanen, Tapani A.

2015-01-01

Graphical abstract: - Highlights: • Microstructured polymer surfaces with selective 3-D anisotropy were created. • Selective UV treatment was performed to alter surface wettability. • Removable meshes resembling a photomask were applied during UV treatment. • Micropatterning by viscous polymer on solid surface was performed. - Abstract: While the conventional photomask technique gives only two-dimensional anisotropies, in this study we fabricated microstructured polymer surfaces with a selective three-dimensional anisotropy. With the applied removable mesh, we were able to confine the contacting area between the surface and photoinitiator and provide three-dimensional wettability anisotropies. Different types of meshes were used depending on the desired micropatterns shape, size and substrate material. The results revealed the three-dimensional anisotropic micropits pattern with depth profiles, which would be applicable for the confinement and patterning of cells and biomolecules. In addition, the proposed method is applicable for creating selectively activated polymer surface as a substrate for further atomic layer deposition. Moreover, we demonstrate a low cost and fast mass productive method for patterning a viscous polymer liquid in a micro-sized scale

Two- and three-dimensional CT analysis of ankle fractures

International Nuclear Information System (INIS)

Magid, D.; Fishman, E.K.; Ney, D.R.; Kuhlman, J.E.

1988-01-01

CT with coronal and sagittal reformatting (two-dimensional CT) and animated volumetric image rendering (three-dimensional CT) was used to assess ankle fractures. Partial volume limits transaxial CT in assessments of horizontally oriented structures. Two-dimensional CT, being orthogonal to the plafond, superior mortise, talar dome, and tibial epiphysis, often provides the most clinically useful images. Two-dimensional CT is most useful in characterizing potentially confusing fractures, such as Tillaux (anterior tubercle), triplane, osteochondral talar dome, or nondisplaced talar neck fractures, and it is the best study to confirm intraarticular fragments. Two-and three-dimensional CT best indicate the percentage of articular surface involvement and best demonstrate postoperative results or complications (hardware migration, residual step-off, delayed union, DJD, AVN, etc). Animated three-dimensional images are the preferred means of integrating the two-dimensional findings for surgical planning, as these images more closely simulate the clinical problem

Evaluation of three-dimensional virtual perception of garments

Science.gov (United States)

Aydoğdu, G.; Yeşilpinar, S.; Erdem, D.

2017-10-01

In recent years, three-dimensional design, dressing and simulation programs came into prominence in the textile industry. By these programs, the need to produce clothing samples for every design in design process has been eliminated. Clothing fit, design, pattern, fabric and accessory details and fabric drape features can be evaluated easily. Also, body size of virtual mannequin can be adjusted so more realistic simulations can be created. Moreover, three-dimensional virtual garment images created by these programs can be used while presenting the product to end-user instead of two-dimensional photograph images. In this study, a survey was carried out to investigate the visual perception of consumers. The survey was conducted for three different garment types, separately. Questions about gender, profession etc. was asked to the participants and expected them to compare real samples and artworks or three-dimensional virtual images of garments. When survey results were analyzed statistically, it is seen that demographic situation of participants does not affect visual perception and three-dimensional virtual garment images reflect the real sample characteristics better than artworks for each garment type. Also, it is reported that there is no perception difference depending on garment type between t-shirt, sweatshirt and tracksuit bottom.

The Bio Bay Game: Three-Dimensional Learning of Biomagnification.

Science.gov (United States)

Jasti, Chandana; Lauren, Hillary; Wallon, Robert C; Hug, Barbara

2016-01-01

Pressing concerns about sustainability and the state of the environment amplify the need to teach students about the connections between ecosystem health, toxicology, and human health. Additionally, the Next Generation Science Standards call for three-dimensional science learning, which integrates disciplinary core ideas, scientific practices, and crosscutting concepts. The Bio Bay Game is a way to teach students about the biomagnification of toxicants across trophic levels while engaging them in three-dimensional learning. In the game, the class models the biomagnification of mercury in a simple aquatic food chain as they play the roles of anchovies, tuna, and humans. While playing, the class generates data, which they analyze after the game to graphically visualize the buildup of toxicants. Students also read and discuss two articles that draw connections to a real-world case. The activity ends with students applying their understanding to evaluate the game as a model of biomagnification. Throughout the activity, students practice modeling and data analysis and engage with the crosscutting concepts of patterns and cause and effect to develop an understanding of core ideas about the connections between humans and the environment.

Three-dimensional reconstruction and visualization system for medical images

International Nuclear Information System (INIS)

Preston, D.F.; Batnitzky, S.; Kyo Rak Lee; Cook, P.N.; Cook, L.T.; Dwyer, S.J.

1982-01-01

A three-dimensional reconstruction and visualization system could be of significant advantage in medical application such as neurosurgery and radiation treatment planning. The reconstructed anatomic structures from CT head scans could be used in a head stereotactic system to help plan the surgical procedure and the radiation treatment for a brain lesion. Also, the use of three-dimensional reconstruction algorithm provides for quantitative measures such as volume and surface area estimation of the anatomic features. This aspect of the three-dimensional reconstruction system may be used to monitor the progress or staging of a disease and the effects of patient treatment. Two cases are presented to illustrate the three-dimensional surface reconstruction and visualization system

Three-dimensional labeling program for elucidation of the geometric properties of biological particles in three-dimensional space.

Science.gov (United States)

Nomura, A; Yamazaki, Y; Tsuji, T; Kawasaki, Y; Tanaka, S

1996-09-15

For all biological particles such as cells or cellular organelles, there are three-dimensional coordinates representing the centroid or center of gravity. These coordinates and other numerical parameters such as volume, fluorescence intensity, surface area, and shape are referred to in this paper as geometric properties, which may provide critical information for the clarification of in situ mechanisms of molecular and cellular functions in living organisms. We have established a method for the elucidation of these properties, designated the three-dimensional labeling program (3DLP). Algorithms of 3DLP are so simple that this method can be carried out through the use of software combinations in image analysis on a personal computer. To evaluate 3DLP, it was applied to a 32-cell-stage sea urchin embryo, double stained with FITC for cellular protein of blastomeres and propidium iodide for nuclear DNA. A stack of optical serial section images was obtained by confocal laser scanning microscopy. The method was found effective for determining geometric properties and should prove applicable to the study of many different kinds of biological particles in three-dimensional space.

Analysis and validation of carbohydrate three-dimensional structures

International Nuclear Information System (INIS)

Lütteke, Thomas

2009-01-01

The article summarizes the information that is gained from and the errors that are found in carbohydrate structures in the Protein Data Bank. Validation tools that can locate these errors are described. Knowledge of the three-dimensional structures of the carbohydrate molecules is indispensable for a full understanding of the molecular processes in which carbohydrates are involved, such as protein glycosylation or protein–carbohydrate interactions. The Protein Data Bank (PDB) is a valuable resource for three-dimensional structural information on glycoproteins and protein–carbohydrate complexes. Unfortunately, many carbohydrate moieties in the PDB contain inconsistencies or errors. This article gives an overview of the information that can be obtained from individual PDB entries and from statistical analyses of sets of three-dimensional structures, of typical problems that arise during the analysis of carbohydrate three-dimensional structures and of the validation tools that are currently available to scientists to evaluate the quality of these structures

Progress of radiotherapy by three-dimensional treatment planning

International Nuclear Information System (INIS)

Imada, Hajime; Nomoto, Satoshi; Takahashi, Hiroyuki; Nakata, Hajime

1998-01-01

The recent progress of three-dimensional radiation treatment planning was reviewed. And clinical cases such as lung cancer and breast cancer are introduced. In the University of Occupational and Development Health, the treatment system FOCUS which is made up of CT simulator and linac was used mainly. Three-dimensional treatment planning was carried for about 90% of 330 patients who underwent radiotherapy for one year. The target becomes to be accurate and dose distribution with all CT slices in radiation field can be confirmed by using three-dimensional radiation treatment planning apparatus. High dose irradiation localized to tumor part is possible. Relations between total dose and volume of normal tissue and/or tumor can be estimated numerically and easily by DVH. A prediction of indication and affection became possible by this procedure. In conclusion, generalization of three-dimensional radiation treatment planning will bring progress of more effective radiotherapy with less adverse reaction. (K.H.). 21 refs

Three Dimensional Polarimetric Neutron Tomography of Magnetic Fields

DEFF Research Database (Denmark)

Sales, Morten; Strobl, Markus; Shinohara, Takenao

2018-01-01

Through the use of Time-of-Flight Three Dimensional Polarimetric Neutron Tomography (ToF 3DPNT) we have for the first time successfully demonstrated a technique capable of measuring and reconstructing three dimensional magnetic field strengths and directions unobtrusively and non-destructively wi......Through the use of Time-of-Flight Three Dimensional Polarimetric Neutron Tomography (ToF 3DPNT) we have for the first time successfully demonstrated a technique capable of measuring and reconstructing three dimensional magnetic field strengths and directions unobtrusively and non...... and reconstructed, thereby providing the proof-of-principle of a technique able to reveal hitherto unobtainable information on the magnetic fields in the bulk of materials and devices, due to a high degree of penetration into many materials, including metals, and the sensitivity of neutron polarisation to magnetic...... fields. The technique puts the potential of the ToF time structure of pulsed neutron sources to full use in order to optimise the recorded information quality and reduce measurement time....

Three-dimensional structure of the γ-secretase complex

International Nuclear Information System (INIS)

Ogura, Toshihiko; Mio, Kazuhiro; Hayashi, Ikuo; Miyashita, Hiroyuki; Fukuda, Rie; Kopan, Raphael; Kodama, Tatsuhiko; Hamakubo, Takao; Iwastubo, Takeshi; Tomita, Taisuke; Sato, Chikara

2006-01-01

γ-Secretase belongs to an atypical class of aspartic proteases that hydrolyzes peptide bonds within the transmembrane domain of substrates, including amyloid-β precursor protein and Notch. γ-Secretase is comprised of presenilin, nicastrin, APH-1, and PEN-2 which form a large multimeric membrane protein complex, the three-dimensional structure of which is unknown. To gain insight into the structure of this complex enzyme, we purified functional γ-secretase complex reconstituted in Sf9 cells and analyzed it using negative stain electron microscopy and 3D reconstruction techniques. Analysis of 2341 negatively stained particle images resulted in the three-dimensional representation of γ-secretase at a resolution of 48 A. The structure occupies a volume of 560 x 320 x 240 A and resembles a flat heart comprised of two oppositely faced, dimpled domains. A low density space containing multiple pores resides between the domains. Some of the dimples in the putative transmembrane region may house the catalytic site. The large dimensions are consistent with the observation that γ-secretase activity resides within a high molecular weight complex

Almost-global tracking for a rigid body with internal rotors

OpenAIRE

Nayak, Aradhana; Banavar, Ravi N.

2017-01-01

Almost-global orientation trajectory tracking for a rigid body with external actuation has been well studied in the literature, and in the geometric setting as well. The tracking control law relies on the fact that a rigid body is a simple mechanical system (SMS) on the $3-$dimensional group of special orthogonal matrices. However, the problem of designing feedback control laws for tracking using internal actuation mechanisms, like rotors or control moment gyros, has received lesser attention...

Dynamic model of organic pollutant degradation in three dimensional packed bed electrode reactor.

Science.gov (United States)

Pang, Tianting; Wang, Yan; Yang, Hui; Wang, Tianlei; Cai, Wangfeng

2018-04-21

A dynamic model of semi-batch three-dimensional electrode reactor was established based on the limiting current density, Faraday's law, mass balance and a series of assumptions. Semi-batch experiments of phenol degradation were carried out in a three-dimensional electrode reactor packed with activated carbon under different conditions to verify the model. The factors such as the current density, the electrolyte concentration, the initial pH value, the flow rate of organic and the initial organic concentration were examined to know about the pollutant degradation in the three-dimensional electrode reactor. The various concentrations and logarithm of concentration of phenol with time were compared with the dynamic model. It was shown that the calculated data were in good agreement with experimental data in most cases. Copyright © 2018 Elsevier Ltd. All rights reserved.

Application of three-dimensional CT reconstruction cranioplasty

International Nuclear Information System (INIS)

Yan Shuli; Yun Yongxing; Wan Kunming; Qiu Jian

2011-01-01

Objective: To study the application of three-dimensional CT reconstruction in cranioplasty. Methods: 46 patients with skull defect were divided into two group. One group underwent CT examination and three-dimensional reconstruction, and then the Titanium nets production company manufactured corresponding titanium meshes were shaped those data before the operation. The other group received traditional operation in which titanium meshes were shaped during operation. The average time of operation were compared. Results: The average time of operation of the first group is 86.6±13.6 mins, and that of the second group is 115±15.0 mins. The difference of average operation time between the two groups was statistically significant. Conclusion: Three-dimensional CT reconstruction techniques contribute to shorten the average operation time, reduce the intensity of neurosurgeon's work and the patien's risk. (authors)

Computational methods for three-dimensional microscopy reconstruction

CERN Document Server

Frank, Joachim

2014-01-01

Approaches to the recovery of three-dimensional information on a biological object, which are often formulated or implemented initially in an intuitive way, are concisely described here based on physical models of the object and the image-formation process. Both three-dimensional electron microscopy and X-ray tomography can be captured in the same mathematical framework, leading to closely-related computational approaches, but the methodologies differ in detail and hence pose different challenges. The editors of this volume, Gabor T. Herman and Joachim Frank, are experts in the respective methodologies and present research at the forefront of biological imaging and structural biology.   Computational Methods for Three-Dimensional Microscopy Reconstruction will serve as a useful resource for scholars interested in the development of computational methods for structural biology and cell biology, particularly in the area of 3D imaging and modeling.

Three-dimensional weight-accumulation algorithm for generating multiple excitation spots in fast optical stimulation

Science.gov (United States)

Takiguchi, Yu; Toyoda, Haruyoshi

2017-11-01

We report here an algorithm for calculating a hologram to be employed in a high-access speed microscope for observing sensory-driven synaptic activity across all inputs to single living neurons in an intact cerebral cortex. The system is based on holographic multi-beam generation using a two-dimensional phase-only spatial light modulator to excite multiple locations in three dimensions with a single hologram. The hologram was calculated with a three-dimensional weighted iterative Fourier transform method using the Ewald sphere restriction to increase the calculation speed. Our algorithm achieved good uniformity of three dimensionally generated excitation spots; the standard deviation of the spot intensities was reduced by a factor of two compared with a conventional algorithm.

Three-dimensional tokamak equilibria and stellarators with two-dimensional magnetic symmetry

International Nuclear Information System (INIS)

Garabedian, P.R.

1997-01-01

Three-dimensional computer codes have been developed to simulate equilibrium, stability and transport in tokamaks and stellarators. Bifurcated solutions of the tokamak problem suggest that three-dimensional effects may be more important than has generally been thought. Extensive calculations have led to the discovery of a stellarator configuration with just two field periods and with aspect ratio 3.2 that has a magnetic field spectrum B mn with toroidal symmetry. Numerical studies of equilibrium, stability and transport for this new device, called the Modular Helias-like Heliac 2 (MHH2), will be presented. (author)

Three-dimensional rendering of segmented object using matlab - biomed 2010.

Science.gov (United States)

Anderson, Jeffrey R; Barrett, Steven F

2010-01-01

The three-dimensional rendering of microscopic objects is a difficult and challenging task that often requires specialized image processing techniques. Previous work has been described of a semi-automatic segmentation process of fluorescently stained neurons collected as a sequence of slice images with a confocal laser scanning microscope. Once properly segmented, each individual object can be rendered and studied as a three-dimensional virtual object. This paper describes the work associated with the design and development of Matlab files to create three-dimensional images from the segmented object data previously mentioned. Part of the motivation for this work is to integrate both the segmentation and rendering processes into one software application, providing a seamless transition from the segmentation tasks to the rendering and visualization tasks. Previously these tasks were accomplished on two different computer systems, windows and Linux. This transition basically limits the usefulness of the segmentation and rendering applications to those who have both computer systems readily available. The focus of this work is to create custom Matlab image processing algorithms for object rendering and visualization, and merge these capabilities to the Matlab files that were developed especially for the image segmentation task. The completed Matlab application will contain both the segmentation and rendering processes in a single graphical user interface, or GUI. This process for rendering three-dimensional images in Matlab requires that a sequence of two-dimensional binary images, representing a cross-sectional slice of the object, be reassembled in a 3D space, and covered with a surface. Additional segmented objects can be rendered in the same 3D space. The surface properties of each object can be varied by the user to aid in the study and analysis of the objects. This inter-active process becomes a powerful visual tool to study and understand microscopic objects.

Evaluation of diagnostic quality in musculoskeletal three-dimensional CT scans

International Nuclear Information System (INIS)

Vannier, M.W.; Hildebolt, C.F.; Gilula, L.A.; Sutherland, C.J.; Offutt, C.J.; Drebin, R.; Mantle, M.; Giordono, T.A.

1988-01-01

A major application of three-dimensional computed tomography (CT) is in the imaging of the skeleton. Three-dimensional CT has an important role in determining the presence and extent of congenital and acquired orthopedic abnormalities. The objective of this study was to compare the diagnostic sensitivity and specificity of three-dimensional CT, planar CT, and plain radiography in the detection and characterization of orthopedic abnormalities. Three-dimensional CT scan reconstructions were obtained by two methods, surface reconstruction and volumetric techniques. Seventy patients were imaged with CT, three-dimensional CT, and plain radiography. The consensus opinion of experts with access to all images plus clinical history, surgical findings, and follow-up findings were taken as truth. Expert radiologists read these cases in a blinded fashion. The results were compared using receiver operating characteristic (ROC) analysis. The diagnostic value of each three-dimensional reconstruction method and the parameters used to perform the reconstructions were evaluated

The use of virtual reality to reimagine two-dimensional representations of three-dimensional spaces

Science.gov (United States)

Fath, Elaine

2015-03-01

A familiar realm in the world of two-dimensional art is the craft of taking a flat canvas and creating, through color, size, and perspective, the illusion of a three-dimensional space. Using well-explored tricks of logic and sight, impossible landscapes such as those by surrealists de Chirico or Salvador Dalí seem to be windows into new and incredible spaces which appear to be simultaneously feasible and utterly nonsensical. As real-time 3D imaging becomes increasingly prevalent as an artistic medium, this process takes on an additional layer of depth: no longer is two-dimensional space restricted to strategies of light, color, line and geometry to create the impression of a three-dimensional space. A digital interactive environment is a space laid out in three dimensions, allowing the user to explore impossible environments in a way that feels very real. In this project, surrealist two-dimensional art was researched and reimagined: what would stepping into a de Chirico or a Magritte look and feel like, if the depth and distance created by light and geometry were not simply single-perspective illusions, but fully formed and explorable spaces? 3D environment-building software is allowing us to step into these impossible spaces in ways that 2D representations leave us yearning for. This art project explores what we gain--and what gets left behind--when these impossible spaces become doors, rather than windows. Using sketching, Maya 3D rendering software, and the Unity Engine, surrealist art was reimagined as a fully navigable real-time digital environment. The surrealist movement and its key artists were researched for their use of color, geometry, texture, and space and how these elements contributed to their work as a whole, which often conveys feelings of unexpectedness or uneasiness. The end goal was to preserve these feelings while allowing the viewer to actively engage with the space.

Fluctuations and symmetries in two-dimensional active gels.

Science.gov (United States)

Sarkar, N; Basu, A

2011-04-01

Motivated by the unique physical properties of biological active matter, e.g., cytoskeletal dynamics in eukaryotic cells, we set up effective two-dimensional (2d) coarse-grained hydrodynamic equations for the dynamics of thin active gels with polar or nematic symmetries. We use the well-known three-dimensional (3d) descriptions (K. Kruse et al., Eur. Phys. J. E 16, 5 (2005); A. Basu et al., Eur. Phys. J. E 27, 149 (2008)) for thin active-gel samples confined between parallel plates with appropriate boundary conditions to derive the effective 2d constitutive relations between appropriate thermodynamic fluxes and generalised forces for small deviations from equilibrium. We consider three distinct cases, characterised by spatial symmetries and boundary conditions, and show how such considerations dictate the structure of the constitutive relations. We use these to study the linear instabilities, calculate the correlation functions and the diffusion constant of a small tagged particle, and elucidate their dependences on the activity or nonequilibrium drive.

Vortex statistics for turbulence in a container with rigid boundaries

DEFF Research Database (Denmark)

Clercx, H.J.H.; Nielsen, A.H.

2000-01-01

The evolution of vortex statistics for decaying two-dimensional turbulence in a square container with rigid no-slip walls is compared with a few available experimental results and with the scaling theory of two-dimensional turbulent decay as proposed by Carnevale et al. Power-law exponents......, computed from an ensemble average of several numerical runs, coincide with some experimentally obtained values, but not with data obtained from numerical simulations of decaying two-dimensional turbulence with periodic boundary conditions....

Three-dimensional echocardiography of normal and pathologic mitral valve: a comparison with two-dimensional transesophageal echocardiography

NARCIS (Netherlands)

Salustri, A.; Becker, A. E.; van Herwerden, L.; Vletter, W. B.; ten Cate, F. J.; Roelandt, J. R.

1996-01-01

This study was done to ascertain whether three-dimensional echocardiography can facilitate the diagnosis of mitral valve abnormalities. The value of the additional information provided by three-dimensional echocardiography compared with two-dimensional multiplane transesophageal echocardiography for

Semiconductor Three-Dimensional Photonic Crystals with Novel Layer-by-Layer Structures

Directory of Open Access Journals (Sweden)

Satoshi Iwamoto

2016-05-01

Full Text Available Three-dimensional photonic crystals (3D PhCs are a fascinating platform for manipulating photons and controlling their interactions with matter. One widely investigated structure is the layer-by-layer woodpile structure, which possesses a complete photonic bandgap. On the other hand, other types of 3D PhC structures also offer various possibilities for controlling light by utilizing the three dimensional nature of structures. In this article, we discuss our recent research into novel types of layer-by-layer structures, including the experimental demonstration of a 3D PhC nanocavity formed in a <110>-layered diamond structure and the realization of artificial optical activity in rotationally stacked woodpile structures.

Insulin as a model to teach three-dimensional structure of proteins

Directory of Open Access Journals (Sweden)

João Batista Teixeira da Rocha

2018-02-01

Proteins are the most ubiquitous macromolecules found in the living cells and have innumerous physiological functions. Therefore, it is fundamental to build a solid knowledge about the proteins three dimensional structure to better understand the living state. The hierarchical structure of proteins is usually studied in the undergraduate discipline of Biochemistry. Here we described pedagogical interventions designed to increase the preservice teacher chemistry students’ knowledge about protein structure. The activities were made using alternative and cheap materials to encourage the application of these simple methodologies by the future teachers in the secondary school. From the primary structure of insulin chains, students had to construct a three-dimensional structure of insulin. After the activities, the students highlighted an improvement of their previous knowledge about proteins structure. The construction of a tridimensional model together with other activities seems to be an efficient way to promote the learning about the structure of proteins to undergraduate students. The methodology used was inexpensiveness and simple and it can be used both in the university and in the high-school.

Study of the nonlinear three-dimensional Debye screening in plasmas

International Nuclear Information System (INIS)

Lin Chang; Zhao Jinbao; Zhang Xiulian

2000-01-01

The nonlinear three-dimensional Debye screening in plasmas is investigated. New analytical solutions for the three-dimensional Poisson equation have been obtained for the nonlinear Debye potential for the first time. We derive exact analytical expression for the special case of the nonlinear three-dimensional Debye screening in plasmas. (orig.)

Heat engine in the three-dimensional spacetime

Energy Technology Data Exchange (ETDEWEB)

Mo, Jie-Xiong [Institute of Theoretical Physics, Lingnan Normal University,Zhanjiang, 524048, Guangdong (China); Department of Physics, Lingnan Normal University,Zhanjiang, 524048, Guangdong (China); Liang, Feng [Department of Physics, Lingnan Normal University,Zhanjiang, 524048, Guangdong (China); Li, Gu-Qiang [Institute of Theoretical Physics, Lingnan Normal University,Zhanjiang, 524048, Guangdong (China); Department of Physics, Lingnan Normal University,Zhanjiang, 524048, Guangdong (China)

2017-03-02

We define a kind of heat engine via three-dimensional charged BTZ black holes. This case is quite subtle and needs to be more careful. The heat flow along the isochores does not equal to zero since the specific heat C{sub V}≠0 and this point completely differs from the cases discussed before whose isochores and adiabats are identical. So one cannot simply apply the paradigm in the former literatures. However, if one introduces a new thermodynamic parameter associated with the renormalization length scale, the above problem can be solved. We obtain the analytical efficiency expression of the three-dimensional charged BTZ black hole heat engine for two different schemes. Moreover, we double check with the exact formula. Our result presents the first specific example for the sound correctness of the exact efficiency formula. We argue that the three-dimensional charged BTZ black hole can be viewed as a toy model for further investigation of holographic heat engine. Furthermore, we compare our result with that of the Carnot cycle and extend the former result to three-dimensional spacetime. In this sense, the result in this paper would be complementary to those obtained in four-dimensional spacetime or ever higher. Last but not the least, the heat engine efficiency discussed in this paper may serve as a criterion to discriminate the two thermodynamic approaches introduced in ref. https://www.doi.org/10.1103/PhysRevD.92.124069 and our result seems to support the approach which introduces a new thermodynamic parameter R=r{sub 0}.

Subjective figure reversal in two- and three-dimensional perceptual space.

Science.gov (United States)

Radilová, J; Radil-Weiss, T

1984-08-01

A permanently illuminated pattern of Mach's truncated pyramid can be perceived according to the experimental instruction given, either as a three-dimensional reversible figure with spontaneously changing convex and concave interpretation (in one experiment), or as a two-dimensional reversible figure-ground pattern (in another experiment). The reversal rate was about twice as slow, without the subjects being aware of it, if it was perceived as a three-dimensional figure compared to the situation when it was perceived as two-dimensional. It may be hypothetized that in the three-dimensional case, the process of perception requires more sequential steps than in the two-dimensional one.

Analysis of the Behaviour of Semi Rigid Steel End Plate Connections

Directory of Open Access Journals (Sweden)

Bahaz A.

2018-01-01

Full Text Available The analysis of steel-framed building structures with full strength beam to column joints is quite standard nowadays. Buildings utilizing such framing systems are widely used in design practice. However, there is a growing recognition of significant benefits in designing joints as partial strength/semi-rigid. The design of joints within this partial strength/semi-rigid approach is becoming more and more popular. This requires the knowledge of the full nonlinear moment-rotation behaviour of the joint, which is also a design parameter. The rotational behaviour of steel semi rigid connections can be studied using the finite element method for the following three reasons: i such models are inexpensive; ii they allow the understanding of local effects, which are difficult to measure accurately physically, and iii they can be used to generate extensive parametric studies. This paper presents a three-dimensional finite element model using ABAQUS software in order to identify the effect of different parameters on the behaviour of semi rigid steel beam to column end plate connections. Contact and sliding between different elements, bolt pretension and geometric and material non-linearity are included in this model. A parametric study is conducted using a model of two end-plate configurations: flush and extended end plates. The studied parameters were as follows: bolts type, end plate thickness and column web stiffener. Then, the model was calibrated and validated with experimental results taken from the literature and with the model proposed by Eurocode3. The procedure for determining the moment–rotation curve using finite element analysis is also given together with a brief explanation of how the design moment resistance and the initial rotational stiffness of the joint are obtained.

Three-Dimensional Reconstruction of Sandpile Interiors

Science.gov (United States)

Seidler, G. T.

2001-03-01

The granular bed, or sandpile, has become one of the condensed matter physicist's favorite systems. In addition to conceptual appeal, the simplest sandpile of monodisperse hard spheres is a valuable model system for understanding powders, liquids, and metallic glasses. Any fundamental approach to the transport and mechanical properties of three-dimensional mesoscale disordered materials must follow from a thorough understanding of their structure. However, in the overwhelming majority of cases, structure measurements have been limited to the mean filling fraction and the structural autocorrelation function. This is particularly unfortunate in the ongoing sandpile renaissance, where some of the most interesting questions concern structure and the relationship between structure and dynamics. I will discuss the combination of synchrotron x-ray microtomography and computer vision algorithms to perform three-dimensional virtual reconstructions of real sandpiles. This technique is rapid and noninvasive, and is applicable to samples large enough to separate bulk and boundary properties. The resulting complete knowledge of structure can be used to calculate otherwise inaccessible correlation functions. I will present results for several measures of the bond-orientational order in three-dimensional sandpiles, including fabric tensors and nematic order parameters.

A plastic surgery application in evolution: three-dimensional printing.

Science.gov (United States)

Gerstle, Theodore L; Ibrahim, Ahmed M S; Kim, Peter S; Lee, Bernard T; Lin, Samuel J

2014-02-01

Three-dimensional printing represents an evolving technology still in its infancy. Currently, individuals and small business entities have the ability to manufacture physical objects from digital renderings, computer-aided design, and open source files. Design modifications and improvements in extrusion methods have made this technology much more affordable. This article explores the potential uses of three-dimensional printing in plastic surgery. A review was performed detailing the known uses of three-dimensional printing in medicine. The potential applications of three-dimensional printing in plastic surgery are discussed. Various applications for three-dimensional printing technology have emerged in medicine, including printing organs, printing body parts, bio-printing, and computer-aided tissue engineering. In plastic surgery, these tools offer various prospective applications for surgical planning, resident education, and the development of custom prosthetics. Numerous applications exist in medicine, including the printing of devices, implants, tissue replacements, and even whole organs. Plastic surgeons may likely find this technology indispensable in surgical planning, education, and prosthetic device design and development in the near future.

Three-dimensional (3D) analysis of the temporomandibular joint

DEFF Research Database (Denmark)

Kitai, N.; Kreiborg, S.; Murakami, S.

Symposium Orthodontics 2001: Where are We Now? Where are We Going?, three-dimensional analysis, temporomandibular joint......Symposium Orthodontics 2001: Where are We Now? Where are We Going?, three-dimensional analysis, temporomandibular joint...

Three-dimensional imaging utilizing energy discrimination

International Nuclear Information System (INIS)

Gunter, D.L.; Hoffman, K.R.; Beck, R.N.

1990-01-01

An algorithm is proposed for three-dimensional image reconstruction in nuclear medicine which uses scattered radiation rather than multiple projected images to determine the source depth within the body. Images taken from numerous energy windows are combined to construct the source distribution in the body. The gamma-ray camera is not moved during the imaging process. Experiments with both Tc-99m and Ga-67 demonstrate that two channels of depth information can be extracted from the low energy images produced by scattered radiation. By combining this technique with standard SPECT reconstruction using multiple projections the authors anticipate much improved spatial resolution in the overall three-dimensional reconstruction

Three-dimensional compound comparison methods and their application in drug discovery.

Science.gov (United States)

Shin, Woong-Hee; Zhu, Xiaolei; Bures, Mark Gregory; Kihara, Daisuke

2015-07-16

Virtual screening has been widely used in the drug discovery process. Ligand-based virtual screening (LBVS) methods compare a library of compounds with a known active ligand. Two notable advantages of LBVS methods are that they do not require structural information of a target receptor and that they are faster than structure-based methods. LBVS methods can be classified based on the complexity of ligand structure information utilized: one-dimensional (1D), two-dimensional (2D), and three-dimensional (3D). Unlike 1D and 2D methods, 3D methods can have enhanced performance since they treat the conformational flexibility of compounds. In this paper, a number of 3D methods will be reviewed. In addition, four representative 3D methods were benchmarked to understand their performance in virtual screening. Specifically, we tested overall performance in key aspects including the ability to find dissimilar active compounds, and computational speed.

Three dimensional analysis of laterally loaded piles

International Nuclear Information System (INIS)

Yilmaz, C.

1987-01-01

In this study static analysis of laterally loaded pile is studied by the three models. The first model is the beam on discrete elastic springs. This model is analyzed using a flexibility method. The second model is the beam on a two-parameter elastic foundation. This model is analyzed using the linear finite element method. The third model is the finite element model, using the three-dimensional iso-parametric parabolic brick element. Three-dimensional pile group analysis is also performed using elastic constants of single pile obtained by any one of the above analyses. The main objective is to develop computer programs for each model related to single piles and to group analysis. Then, the deflections, rotations, moments, shears, stresses and strains of the single pile are obtained at any arbitrary point. Comparison is made between each model and with other studies such as Poulos 1971, Desai and Appel 1976. In addition, to provide a benchmark of three-dimensional finite element analysis, the Boussinesq problem is analyzed. (orig.)

Three-dimensional attached viscous flow basic principles and theoretical foundations

CERN Document Server

Hirschel, Ernst Heinrich; Kordulla, Wilhelm

2014-01-01

Viscous flow is usually treated in the frame of boundary-layer theory and as a two-dimensional flow. At best, books on boundary layers provide the describing equations for three-dimensional boundary layers, and solutions only for certain special cases.   This book presents the basic principles and theoretical foundations of three-dimensional attached viscous flows as they apply to aircraft of all kinds. Though the primary flight speed range is that of civil air transport vehicles, flows past other flying vehicles up to hypersonic speeds are also considered. Emphasis is put on general three-dimensional attached viscous flows and not on three-dimensional boundary layers, as this wider scope is necessary in view of the theoretical and practical problems that have to be overcome in practice.   The specific topics covered include weak, strong, and global interaction; the locality principle; properties of three-dimensional viscous flows; thermal surface effects; characteristic properties; wall compatibility con...

Static and dynamic properties of three-dimensional dot-type magnonic crystals

International Nuclear Information System (INIS)

Maksymov, Artur; Spinu, Leonard

2016-01-01

The static and dynamic magnetization of three-dimensional magnonic metamaterials has been investigated. By numerical means it was analyzed the impact of space dimensionality on the properties of magnonic crystal with unit cell consisting of four dots. It is find out the possibility of multi-vortex core formation which is related to the increasing of the crystal height by three-dimensional periodicity of single crystal layer. Additionally is provided the analysis of ferromagnetic resonance phenomenon for two-dimensional and three-dimensional structures. For the unsaturated magnetization of three-dimensional crystal the several pronounced resonance frequencies were detected.

Static and dynamic properties of three-dimensional dot-type magnonic crystals

Energy Technology Data Exchange (ETDEWEB)

Maksymov, Artur, E-mail: maxyartur@gmail.com [Advanced Materials Research Institute, University of New Orleans, LA 70148 (United States); Department of General Physics, Chernivtsi National University, Chernivtsi 58012 (Ukraine); Spinu, Leonard [Advanced Materials Research Institute, University of New Orleans, LA 70148 (United States); Department of Physics, University of New Orleans, New Orleans, LA 70148 (United States)

2016-04-01

The static and dynamic magnetization of three-dimensional magnonic metamaterials has been investigated. By numerical means it was analyzed the impact of space dimensionality on the properties of magnonic crystal with unit cell consisting of four dots. It is find out the possibility of multi-vortex core formation which is related to the increasing of the crystal height by three-dimensional periodicity of single crystal layer. Additionally is provided the analysis of ferromagnetic resonance phenomenon for two-dimensional and three-dimensional structures. For the unsaturated magnetization of three-dimensional crystal the several pronounced resonance frequencies were detected.

Three-Dimensional Flows

CERN Document Server

Araujo, Vitor; Viana, Marcelo

2010-01-01

In this book, the authors present the elements of a general theory for flows on three-dimensional compact boundaryless manifolds, encompassing flows with equilibria accumulated by regular orbits. The book aims to provide a global perspective of this theory and make it easier for the reader to digest the growing literature on this subject. This is not the first book on the subject of dynamical systems, but there are distinct aspects which together make this book unique. Firstly, this book treats mostly continuous time dynamical systems, instead of its discrete counterpart, exhaustively treated

Three-diemensional materials science: An intersection of three-dimensional reconstructions and simulations

DEFF Research Database (Denmark)

Thornton, Katsuyo; Poulsen, Henning Friis

2008-01-01

The recent development of experimental techniques that rapidly reconstruct the three-dimensional microstructures of solids has given rise to new possibilities for developing a deeper understanding of the evolution of microstructures and the effects of microstructures on materials properties. Comb...... an overview of this emerging field of materials science, as well as brief descriptions of selected methods and their applicability.......The recent development of experimental techniques that rapidly reconstruct the three-dimensional microstructures of solids has given rise to new possibilities for developing a deeper understanding of the evolution of microstructures and the effects of microstructures on materials properties....... Combined with three-dimensional (3D) simulations and analyses that are capable of handling the complexity of these microstructures, 3D reconstruction, or tomography, has become a powerful tool that provides clear insights into materials processing and properties. This introductory article provides...

Three-dimensional brain mapping using fMRI

International Nuclear Information System (INIS)

Fukunaga, Masaki; Tanaka, Chuzo; Umeda, Masahiro; Ebisu, Toshihiko; Aoki, Ichio; Higuchi, Toshihiro; Naruse, Shoji.

1997-01-01

Functional mapping of the activated brain, the location and extent of the activated area were determined, during motor tasks and sensory stimulation using fMRI superimposed on 3D anatomical MRI. Twelve volunteers were studied. The fMR images were acquired using a 2D gradient echo echo planar imaging sequence. The 3D anatomical MR images of the whole brain were acquired using a conventional 3D gradient echo sequence. Motor tasks were sequential opposition of fingers, clenching a hand and elbow flexion. Somatosensory stimulation were administered by scrubbing the palm and sole with a washing sponge. Visual stimulation consisted of full visual field stimulation. Data were analyzed by the cross-correlation method. Transversal fMR images and anatomical images were reconstructed using both volume-, surface-rendering methods, and reconstructed for coronal and sagittal sections. Activated areas were expressed using the three primary colors. Motor tasks activated the contralateral primary motor area (M1), the primary somatosensory area (S1) and the supplementary motor area (SMA). Somatosensory tasks activated the contralateral S1, M1 and secondary sensory area (S2). Activated areas during full visual field stimulation was observed in the bilateral occipital lobe, including both the primary cortex. Three-dimensional brain mapping allowed visualization of the anatomical location and extent of the activated brain during both motor task and sensory stimulation. Using this method we could obtain a functional map similar to the Penfield's schema. (author)

New method for solving three-dimensional Schroedinger equation

International Nuclear Information System (INIS)

Melezhik, V.S.

1990-01-01

The method derived recently for solving a multidimensional scattering problem is applied to a three-dimensional Schroedinger equation. As compared with direct three-dimensional calculations of finite elements and finite differences, this approach gives sufficiently accurate upper and lower approximations to the helium-atom binding energy, which demonstrates its efficiency. 15 refs.; 1 fig.; 2 tabs

Stochastic self-propagating star formation in three-dimensional disk galaxy simulations

International Nuclear Information System (INIS)

Statler, T.; Comins, N.; Smith, B.F.

1983-01-01

Stochastic self-propagating star formation (SSPSF) is a process of forming new stars through the compression of the interstellar medium by supernova shock waves. Coupling this activity with galactic differential rotation produces spiral structure in two-dimensional disk galaxy simulations. In this paper the first results of a three-dimensional SSPSF simulation of disk galaxies are reported. Our model generates less impressive spirals than do the two-dimensional simulations. Although some spirals do appear in equilibrium, more frequently we observe spirals as non-equilibrium states of the models: as the spiral arms evolve, they widen until the spiral structure is no longer discernible. The two free parameters that we vary in this study are the probability of star formation due to a recent, nearby explosion, and the relaxation time for the interstellar medium to return to a condition of maximum star formation after it has been cleared out by an explosion and subsequent star formation. We find that equilibrium spiral structure is formed over a much smaller range of these parameters in our three-dimensional SSPSF models than in similar two-dimensional models. We discuss possible reasons for these results as well as improvements on the model which are being explored

Resonance fluorescence based two- and three-dimensional atom localization

Science.gov (United States)

Wahab, Abdul; Rahmatullah; Qamar, Sajid

2016-06-01

Two- and three-dimensional atom localization in a two-level atom-field system via resonance fluorescence is suggested. For the two-dimensional localization, the atom interacts with two orthogonal standing-wave fields, whereas for the three-dimensional atom localization, the atom interacts with three orthogonal standing-wave fields. The effect of the detuning and phase shifts associated with the corresponding standing-wave fields is investigated. A precision enhancement in position measurement of the single atom can be noticed via the control of the detuning and phase shifts.

Investigating Hydrocarbon Seep Environments with High-Resolution, Three-Dimensional Geographic Visualizations.

Science.gov (United States)

Doolittle, D. F.; Gharib, J. J.; Mitchell, G. A.

2015-12-01

Detailed photographic imagery and bathymetric maps of the seafloor acquired by deep submergence vehicles such as Autonomous Underwater Vehicles (AUV) and Remotely Operated Vehicles (ROV) are expanding how scientists and the public view and ultimately understand the seafloor and the processes that modify it. Several recently acquired optical and acoustic datasets, collected during ECOGIG (Ecosystem Impacts of Oil and Gas Inputs to the Gulf) and other Gulf of Mexico expeditions using the National Institute for Undersea Science Technology (NIUST) Eagle Ray, and Mola Mola AUVs, have been fused with lower resolution data to create unique three-dimensional geovisualizations. Included in these data are multi-scale and multi-resolution visualizations over hydrocarbon seeps and seep related features. Resolution of the data range from 10s of mm to 10s of m. When multi-resolution data is integrated into a single three-dimensional visual environment, new insights into seafloor and seep processes can be obtained from the intuitive nature of three-dimensional data exploration. We provide examples and demonstrate how integration of multibeam bathymetry, seafloor backscatter data, sub-bottom profiler data, textured photomosaics, and hull-mounted multibeam acoustic midwater imagery are made into a series a three-dimensional geovisualizations of actively seeping sites and associated chemosynthetic communities. From these combined and merged datasets, insights on seep community structure, morphology, ecology, fluid migration dynamics, and process geomorphology can be investigated from new spatial perspectives. Such datasets also promote valuable inter-comparisons of sensor resolution and performance.

Method for coupling two-dimensional to three-dimensional discrete ordinates calculations

International Nuclear Information System (INIS)

Thompson, J.L.; Emmett, M.B.; Rhoades, W.A.; Dodds, H.L. Jr.

1985-01-01

A three-dimensional (3-D) discrete ordinates transport code, TORT, has been developed at the Oak Ridge National Laboratory for radiation penetration studies. It is not feasible to solve some 3-D penetration problems with TORT, such as a building located a large distance from a point source, because (a) the discretized 3-D problem is simply too big to fit on the computer or (b) the computing time (and corresponding cost) is prohibitive. Fortunately, such problems can be solved with a hybrid approach by coupling a two-dimensional (2-D) description of the point source, which is assumed to be azimuthally symmetric, to a 3-D description of the building, the region of interest. The purpose of this paper is to describe this hybrid methodology along with its implementation and evaluation in the DOTTOR (Discrete Ordinates to Three-dimensional Oak Ridge Transport) code

Three-Dimensional Graphene Supported Bimetallic Nanocomposites with DNA Regulated-Flexibly Switchable Peroxidase-Like Activity.

Science.gov (United States)

Yuan, Fang; Zhao, Huimin; Zang, Hongmei; Ye, Fei; Quan, Xie

2016-04-20

A synergistic bimetallic enzyme mimetic catalyst, three-dimensional (3D) graphene/Fe3O4-AuNPs, was successfully fabricated which exhibited flexibly switchable peroxidase-like activity. Compared to the traditional 2D graphene-based monometallic composite, the introduced 3D structure, which was induced by the addition of glutamic acid, and bimetallic anchoring approach dramatically improved the catalytic activity, as well as the catalysis velocity and its affinity for substrate. Herein, Fe3O4NPs acted as supporters for AuNPs, which contributed to enhance the efficiency of electron transfer. On the basis of the measurement of Mott-Schottky plots of graphene and metal anchored hybrids, the catalysis mechanism was elucidated by the decrease of Fermi level resulted from the chemical doping behavior. Notably, the catalytic activity was able to be regulated by the adsorption and desorption of single-stranded DNA molecules, which laid a basis for its utilization in the construction of single-stranded DNA-based colorimetric biosensors. This strategy not only simplified the operation process including labeling, modification, and imprinting, but also protected the intrinsic affinity between the target and biological probe. Accordingly, based on the peroxidase-like activity and its controllability, our prepared nanohybrids was successfully adopted in the visualized and label-free sensing detections of glucose, sequence-specific DNA, mismatched nucleotides, and oxytetracycline.

Three-dimensional immobilization of beta-galactosidase on a silicon surface.

Science.gov (United States)

Betancor, Lorena; Luckarift, Heather R; Seo, Jae H; Brand, Oliver; Spain, Jim C

2008-02-01

Many alternative strategies to immobilize and stabilize enzymes have been investigated in recent years for applications in biosensors. The entrapment of enzymes within silica-based nanospheres formed through silicification reactions provides high loading capacities for enzyme immobilization, resulting in high volumetric activity and enhanced mechanical stability. Here we report a strategy for chemically associating silica nanospheres containing entrapped enzyme to a silicon support. beta-galactosidase from E. coli was used as a model enzyme due to its versatility as a biosensor for lactose. The immobilization strategy resulted in a three-dimensional network of silica attached directly at the silicon surface, providing a significant increase in surface area and a corresponding 3.5-fold increase in enzyme loading compared to enzyme attached directly at the surface. The maximum activity recovered for a silicon square sample of 0.5 x 0.5 cm was 0.045 IU using the direct attachment of the enzyme through glutaraldehyde and 0.16 IU when using silica nanospheres. The immobilized beta-galactosidase prepared by silica deposition was stable and retained more than 80% of its initial activity after 10 days at 24 degrees C. The ability to generate three-dimensional structures with enhanced loading capacity for biosensing molecules offers the potential to substantially amplify biosensor sensitivity. (c) 2007 Wiley Periodicals, Inc.

Three-dimensional imagery by encoding sources of X rays

International Nuclear Information System (INIS)

Magnin, Isabelle

1987-01-01

This research thesis addresses the theoretical and practical study of X ray coded sources, and thus notably aims at exploring whether it would be possible to transform a standard digital radiography apparatus (as those operated in radiology hospital departments) into a low cost three-dimensional imagery system. The author first recalls the principle of conventional tomography and improvement attempts, and describes imagery techniques based on the use of encoding openings and source encoding. She reports the modelling of an imagery system based on encoded sources of X ray, and addresses the original notion of three-dimensional response for such a system. The author then addresses the reconstruction method by considering the reconstruction of a plane object, of a multi-plane object, and of real three-dimensional object. The frequency properties and the tomographic capacities of various types of source codes are analysed. She describes a prototype tomography apparatus, and presents and discusses three-dimensional actual phantom reconstructions. She finally introduces a new principle of dynamic three-dimensional radiography which implements an acquisition technique by 'gating code'. The acquisition principle should allow the reconstruction of volumes animated by periodic deformations, such as the heart for example [fr

Three-dimensional oscillator and Coulomb systems reduced from Kaehler spaces

International Nuclear Information System (INIS)

Nersessian, Armen; Yeranyan, Armen

2004-01-01

We define the oscillator and Coulomb systems on four-dimensional spaces with U(2)-invariant Kaehler metric and perform their Hamiltonian reduction to the three-dimensional oscillator and Coulomb systems specified by the presence of Dirac monopoles. We find the Kaehler spaces with conic singularity, where the oscillator and Coulomb systems on three-dimensional sphere and two-sheet hyperboloid originate. Then we construct the superintegrable oscillator system on three-dimensional sphere and hyperboloid, coupled to a monopole, and find their four-dimensional origins. In the latter case the metric of configuration space is a non-Kaehler one. Finally, we extend these results to the family of Kaehler spaces with conic singularities

Supersymmetric quantum mechanics in three-dimensional space, 1

International Nuclear Information System (INIS)

Ui, Haruo

1984-01-01

As a direct generalization of the model of supersymmetric quantum mechanics by Witten, which describes the motion of a spin one-half particle in the one-dimensional space, we construct a model of the supersymmetric quantum mechanics in the three-dimensional space, which describes the motion of a spin one-half particle in central and spin-orbit potentials in the context of the nonrelativistic quantum mechanics. With the simplest choice of the (super) potential, this model is shown to reduce to the model of the harmonic oscillator plus constant spin-orbit potential of unit strength of both positive and negative signs, which was studied in detail in our recent paper in connection with ''accidental degeneracy'' as well as the ''graded groups''. This simplest model is discussed in some detail as an example of the three-dimensional supersymmetric quantum mechanical system, where the supersymmetry is an exact symmetry of the system. More general choice of a polynomial superpotential is also discussed. It is shown that the supersymmetry cannot be spontaneously broken for any polynomial superpotential in our three-dimensional model; this result is contrasted to the corresponding one in the one-dimensional model. (author)

Slab1.0: A three-dimensional model of global subduction zone geometries

Science.gov (United States)

Hayes, Gavin P.; Wald, David J.; Johnson, Rebecca L.

2012-01-01

We describe and present a new model of global subduction zone geometries, called Slab1.0. An extension of previous efforts to constrain the two-dimensional non-planar geometry of subduction zones around the focus of large earthquakes, Slab1.0 describes the detailed, non-planar, three-dimensional geometry of approximately 85% of subduction zones worldwide. While the model focuses on the detailed form of each slab from their trenches through the seismogenic zone, where it combines data sets from active source and passive seismology, it also continues to the limits of their seismic extent in the upper-mid mantle, providing a uniform approach to the definition of the entire seismically active slab geometry. Examples are shown for two well-constrained global locations; models for many other regions are available and can be freely downloaded in several formats from our new Slab1.0 website, http://on.doi.gov/d9ARbS. We describe improvements in our two-dimensional geometry constraint inversion, including the use of ‘average’ active source seismic data profiles in the shallow trench regions where data are otherwise lacking, derived from the interpolation between other active source seismic data along-strike in the same subduction zone. We include several analyses of the uncertainty and robustness of our three-dimensional interpolation methods. In addition, we use the filtered, subduction-related earthquake data sets compiled to build Slab1.0 in a reassessment of previous analyses of the deep limit of the thrust interface seismogenic zone for all subduction zones included in our global model thus far, concluding that the width of these seismogenic zones is on average 30% larger than previous studies have suggested.

Three-Dimensional Compound Comparison Methods and Their Application in Drug Discovery

Directory of Open Access Journals (Sweden)

Woong-Hee Shin

2015-07-01

Full Text Available Virtual screening has been widely used in the drug discovery process. Ligand-based virtual screening (LBVS methods compare a library of compounds with a known active ligand. Two notable advantages of LBVS methods are that they do not require structural information of a target receptor and that they are faster than structure-based methods. LBVS methods can be classified based on the complexity of ligand structure information utilized: one-dimensional (1D, two-dimensional (2D, and three-dimensional (3D. Unlike 1D and 2D methods, 3D methods can have enhanced performance since they treat the conformational flexibility of compounds. In this paper, a number of 3D methods will be reviewed. In addition, four representative 3D methods were benchmarked to understand their performance in virtual screening. Specifically, we tested overall performance in key aspects including the ability to find dissimilar active compounds, and computational speed.

Environmental, Transient, Three-Dimensional, Hydrothermal, Mass Transport Code - FLESCOT

Energy Technology Data Exchange (ETDEWEB)

Onishi, Yasuo [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Bao, Jie [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Glass, Kevin A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Eyler, L. L. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Okumura, Masahiko [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2015-03-28

The purpose of the project was to modify and apply the transient, three-dimensional FLESCOT code to be able to effectively simulate cesium behavior in Fukushima lakes/dam reservoirs, river mouths, and coastal areas. The ultimate objective of the FLESCOT simulation is to predict future changes of cesium accumulation in Fukushima area reservoirs and costal water. These evaluation results will assist ongoing and future environmental remediation activities and policies in a systematic and comprehensive manner.

Outreach activity by using three-dimensional nuclear chart. Understanding nuclear physics and nuclear energy

International Nuclear Information System (INIS)

Koura, Hiroyuki

2015-01-01

A three-dimensional nuclear chart is constructed with toy blocks for usage of outreach activity related on nuclear physics and atomic energy. The height of each block represents quantities like atomic mass per nucleon, the total half-life, etc. The bulk properties of the nuclei can be easily understood by using these charts. Explanations for the energy generation of nuclear fusion and fission are visually given. In addition, we newly set another chart with blocks of fission fragment mass distribution from U-235 + a thermal neutron. As an example, the origin of abundances of rather radioactive isotopes like Sr-90 and Cs-137 is explained which created in nuclear reactor and also distributed in the eastern side of Fukushima prefecture due to the accident of Fukushima-Daiichi Nuclear Power Plant. Using our charts, lectures entitled 'Alchemy of the Universe' were delivered to high schools and public places. (author)

Three-dimensional theory for light-matter interaction

DEFF Research Database (Denmark)

Sørensen, Martin Westring; Sørensen, Anders Søndberg

2008-01-01

We present a full quantum mechanical three dimensional theory describing an electromagnetic field interacting with an ensemble of identical atoms. The theory is constructed such that it describes recent experiments on light-matter quantum interfaces, where the quantum fluctuations of light...... to a dressed state picture, where the light modes are solutions to the diffraction problem, and develop a perturbative expansion in the fluctuations. The fluctuations are due to quantum fluctuations as well as the random positions of the atoms. In this perturbative expansion we show how the quantum...... fluctuations are mapped between atoms and light while the random positioning of the atoms give rise to decay due to spontaneous emission. Furthermore we identify limits, where the full three dimensional theory reduce to the one dimensional theory typically used to describe the interaction....

Three dimensional contact/impact methodology

International Nuclear Information System (INIS)

Kulak, R.F.

1987-01-01

The simulation of three-dimensional interface mechanics between reactor components and structures during static contact or dynamic impact is necessary to realistically evaluate their structural integrity to off-normal loads. In our studies of postulated core energy release events, we have found that significant structure-structure interactions occur in some reactor vessel head closure designs and that fluid-structure interactions occur within the reactor vessel. Other examples in which three-dimensional interface mechanics play an important role are: (1) impact response of shipping casks containing spent fuel, (2) whipping pipe impact on reinforced concrete panels or pipe-to-pipe impact after a pipe break, (3) aircraft crash on secondary containment structures, (4) missiles generated by turbine failures or tornados, and (5) drops of heavy components due to lifting accidents. The above is a partial list of reactor safety problems that require adequate treatment of interface mechanics and are discussed in this paper

Three-dimensional activated reduced graphene oxide nanocup/nickel aluminum layered double hydroxides composite with super high electrochemical and capacitance performances

International Nuclear Information System (INIS)

Lin, Yan; Ruiyi, Li; Zaijun, Li; Junkang, Liu; Yinjun, Fang; Guangli, Wang; Zhiguo, Gu

2013-01-01

The paper reported a three-dimensional activated reduced graphene oxide nanocup/nickel aluminum layered double hydroxides composite (3D-ARGON/NiAl-LDH) with super high electrochemical and capacitance performances. Graphene oxide was reduced by hydrazine in ammonia medium to form three-dimensional reduced graphene oxide nanocup using polystyrene colloidal particle as sacrificial template. The nanocup was then activated by the alkali corrosion and thermal annealing. The 3D-ARGON/NiAl-LDH was finally fabricated by the hydrothermal synthesis via in situ growth of ultrathin NiAl-LDH nanoflakes on the 3D-ARGON in an ethanol medium. The study demonstrated that the composite offers special 3D architecture with a macropore on the rim of a cup and large mesoporous structure on the wall of a cup, which will greatly boost the electron transfer and mass transport during the faradaic redox reaction, and displays excellent electrochemical and capactance performances, including high specific capacitance and rate capability, good charge/discharge stability and long-term cycling life. Its maximum specific capacitance was found to be 2712.7 F g −1 at the current density of 1 A g −1 , which is more than 7-fold that of pure NiAl-LDH, 3-fold that of common reduced graphene oxide/NiAl-LDH and 1.8-fold that of two-dimensional activated reduced graphene oxide/NiAl-LDH. The specific capacitance can remain 1174 F g −1 when the current density increases up to 50 A g −1 . After 5000 cycles at the current density of 30 A g −1 , the capacitance can keep at least 98.9%. This study provides a promising approach for the design and synthesis of graphene-based materials with largely enhanced supercapacitor behaviors, which can be potentially applied in energy storage/conversion devices

Diffraction limited focusing with controllable arbitrary three-dimensional polarization

International Nuclear Information System (INIS)

Chen, Weibin; Zhan, Qiwen

2010-01-01

We propose a new approach that enables full control over the three-dimensional state of polarization and the field distribution near the focus of a high numerical aperture objective lens. By combining the electric dipole radiation and a vectorial diffraction method, the input field at the pupil plane for generating arbitrary three-dimensionally oriented linear polarization at the focal point with a diffraction limited spot size is found analytically by solving the inverse problem. Arbitrary three-dimensional elliptical polarization can be obtained by introducing a second electric dipole oriented in the orthogonal plane with appropriate amplitude and phase differences

Three-dimensional CT imaging of soft-tissue anatomy

International Nuclear Information System (INIS)

Fishman, E.K.; Ney, D.R.; Magid, D.; Kuhlman, J.E.

1988-01-01

Three-dimensional display of computed tomographic data has been limited to skeletal structures. This was in part related to the reconstruction algorithm used, which relied on a binary classification scheme. A new algorithm, volumetric rendering with percentage classification, provides the ability to display three-dimensional images of muscle and soft tissue. A review was conducted of images in 35 cases in which muscle and/or soft tissue were part of the clinical problem. In all cases, individual muscle groups could be clearly identified and discriminated. Branching vessels in the range of 2.3 mm could be identified. Similarly, lymph nodes could be clearly defined. High-resolution three-dimensional images were found to be useful both in providing an increased understanding of complex muscle and soft tissue anatomy and in surgical planning

THREE DIMENSIONAL GRAPHICAL REPRESENTATION OF QUALITY

Directory of Open Access Journals (Sweden)

Vineet V. Kumar

2014-03-01

Full Text Available Quality is an important aspect for every firm in modern era of competition. Every product has tough competition in terms of market reach. The factor, which actually makes any product long run in market, is quality and hence quality is the stepping-stone for success of any firm. For everyone meaning of quality is different. We have seen several economists who have defined quality by considering different factors, but what all of them have common in them is Customer satisfaction. Customer satisfaction is the ultimate result of quality. In three-dimensional graphical representation of quality, optimum quality is obtained by using three-dimensional graph by considering some important factors governing quality of any product, limiting factor, and customer satisfaction.

Blast wave interaction with a rigid surface

International Nuclear Information System (INIS)

Josey, T.; Whitehouse, D.R.; Ripley, R.C.; Dionne, J.P.

2004-01-01

A simple model used to investigate blast wave interactions with a rigid surface is presented. The model uses a constant volume energy source analogue to predict pressure histories at gauges located directly above the charge. A series of two-dimensional axi-symmetric CFD calculations were performed, varying the height of the charge relative to the ground. Pressure histories, along with isopycnic plots are presented to evaluate the effects of placing a charge in close proximity to a rigid surface. When a charge is placed near a solid surface the pressure histories experienced at gauges above the charge indicate the presence of two distinct pressure peaks. The first peak is caused by the primary shock and the second peak is a result of the wave reflections from the rigid surface. As the distance from the charge to the wall is increased the magnitude of the second pressure peak is reduced, provided that the distance between the charge and the gauge is maintained constant. The simple model presented is able to capture significant, predictable flow features. (author)

Application status of three-dimensional CT reconstruction in hepatobiliary surgery

Directory of Open Access Journals (Sweden)

JIANG Chao

2017-02-01

Full Text Available With the development of imaging technology, three-dimensional CT reconstruction has been widely used in hepatobiliary surgery. Three-dimensional CT reconstruction can divide and reconstruct two-dimensional images into three-dimensional images and clearly show the location of lesion and its relationship with the intrahepatic bile duct system. It has an important value in the preoperative assessment of liver volume, diagnosis and treatment decision-making process, intraoperative precise operation, and postoperative individualized management, and promotes the constant development of hepatobiliary surgery and minimally invasive technology, and therefore, it holds promise for clinical application.

Utility of three-dimensional method for diagnosing meniscal lesions

International Nuclear Information System (INIS)

Ohshima, Suguru; Nomura, Kazutoshi; Hirano, Mako; Hashimoto, Noburo; Fukumoto, Tetsuya; Katahira, Kazuhiro

1998-01-01

MRI of the knee is a useful method for diagnosing meniscal tears. Although the spin echo method is usually used for diagnosing meniscal tears, we examined the utility of thin slice scan with the three-dimensional method. We reviewed 70 menisci in which arthroscopic findings were confirmed. In this series, sensitivity was 90.9% for medial meniscal injuries and 68.8% for lateral meniscal injuries. There were 3 meniscal tears in which we could not detect tears on preoperative MRI. We could find tears in two of these cases when re-evaluated using the same MRI. In conclusion, we can get the same diagnostic rate with the three-dimensional method compared with the spin echo method. Scan time of the three-dimensional method is 3 minutes, on the other hand that of spin echo method in 17 minutes. This slice scan with three-dimensional method is useful for screening meniscal injuries before arthroscopy. (author)

On the surprising rigidity of the Pauli exclusion principle

International Nuclear Information System (INIS)

Greenberg, O.W.

1989-01-01

I review recent attempts to construct a local quantum field theory of small violations of the Pauli exclusion principle and suggest a qualitative reason for the surprising rigidity of the Pauli principle. I suggest that small violations can occur in our four-dimensional world as a consequence of the compactification of a higher-dimensional theory in which the exclusion principle is exactly valid. I briefly mention a recent experiment which places a severe limit on possible violations of the exclusion principle. (orig.)

Integration of Computed Tomography and Three-Dimensional Echocardiography for Hybrid Three-Dimensional Printing in Congenital Heart Disease.

Science.gov (United States)

Gosnell, Jordan; Pietila, Todd; Samuel, Bennett P; Kurup, Harikrishnan K N; Haw, Marcus P; Vettukattil, Joseph J

2016-12-01

Three-dimensional (3D) printing is an emerging technology aiding diagnostics, education, and interventional, and surgical planning in congenital heart disease (CHD). Three-dimensional printing has been derived from computed tomography, cardiac magnetic resonance, and 3D echocardiography. However, individually the imaging modalities may not provide adequate visualization of complex CHD. The integration of the strengths of two or more imaging modalities has the potential to enhance visualization of cardiac pathomorphology. We describe the feasibility of hybrid 3D printing from two imaging modalities in a patient with congenitally corrected transposition of the great arteries (L-TGA). Hybrid 3D printing may be useful as an additional tool for cardiologists and cardiothoracic surgeons in planning interventions in children and adults with CHD.

Three-dimensional image reconstruction from stereo DSA

International Nuclear Information System (INIS)

Sakamoto, Kiyoshi; Kotoura, Noriko; Umehara, Takayoshi; Yamada, Eiji; Inaba, Tomohiro; Itou, Hiroshi

1999-01-01

The technique of interventional radiology has spread rapidly in recent years, and three-dimensional information from blood vessel images is being sought to enhance examinations. Stereo digital subtraction angiography (DSA) and rotational DSA were developed for that purpose. However, it is difficult with stereo DSA to observe the image pair during examination and to obtain positional information on blood vessels. Further, the exposure dose is increased in rotational DSA when many mask images need to be collected, and the patient is required to hold his or her breath for a long duration. We therefore devised a technique to construct three-dimensional blood vessel images by employing geometrical information extracted from stereo DSA images using the right and left images. We used a judgment method based on the correlation coefficient, although we had to extract an equal blood vessel from the right and left images to determine the three-dimensional coordinates of the blood vessel. The reconstructed three-dimensional blood vessels were projected from various angles, again by using a virtual focus, and new images were created. These image groups were displayed as rotational images by the animation display function incorporated in the DSA device. This system can observe blood vessel images of the same phase at a free angle, although the image quality is inferior to that of rotational DSA. In addition, because collection of the mask images is reduced, exposure dose can be decreased. Further, the system offers enhanced safety because no mechanical movement of the imaging system is involved. (author)

Evolution of three-dimensional relativistic current sheets and development of self-generated turbulence

Science.gov (United States)

Takamoto, M.

2018-05-01

In this paper, the temporal evolution of three-dimensional relativistic current sheets in Poynting-dominated plasma is studied for the first time. Over the past few decades, a lot of efforts have been conducted on studying the evolution of current sheets in two-dimensional space, and concluded that sufficiently long current sheets always evolve into the so-called plasmoid chain, which provides a fast reconnection rate independent of its resistivity. However, it is suspected that plasmoid chain can exist only in the case of two-dimensional approximation, and would show transition to turbulence in three-dimensional space. We performed three-dimensional numerical simulation of relativistic current sheet using resistive relativistic magnetohydrodynamic approximation. The results showed that the three-dimensional current sheets evolve not into plasmoid chain but turbulence. The resulting reconnection rate is 0.004, which is much smaller than that of plasmoid chain. The energy conversion from magnetic field to kinetic energy of turbulence is just 0.01 per cent, which is much smaller than typical non-relativistic cases. Using the energy principle, we also showed that the plasmoid is always unstable for a displacement in the opposite direction to its acceleration, probably interchange-type instability, and this always results in seeds of turbulence behind the plasmoids. Finally, the temperature distribution along the sheet is discussed, and it is found that the sheet is less active than plasmoid chain. Our finding can be applied for many high-energy astrophysical phenomena, and can provide a basic model of the general current sheet in Poynting-dominated plasma.

A DETERMINISTIC METHOD FOR TRANSIENT, THREE-DIMENSIONAL NUETRON TRANSPORT

International Nuclear Information System (INIS)

S. GOLUOGLU, C. BENTLEY, R. DEMEGLIO, M. DUNN, K. NORTON, R. PEVEY I.SUSLOV AND H.L. DODDS

1998-01-01

A deterministic method for solving the time-dependent, three-dimensional Boltzmam transport equation with explicit representation of delayed neutrons has been developed and evaluated. The methodology used in this study for the time variable of the neutron flux is known as the improved quasi-static (IQS) method. The position, energy, and angle-dependent neutron flux is computed deterministically by using the three-dimensional discrete ordinates code TORT. This paper briefly describes the methodology and selected results. The code developed at the University of Tennessee based on this methodology is called TDTORT. TDTORT can be used to model transients involving voided and/or strongly absorbing regions that require transport theory for accuracy. This code can also be used to model either small high-leakage systems, such as space reactors, or asymmetric control rod movements. TDTORT can model step, ramp, step followed by another step, and step followed by ramp type perturbations. It can also model columnwise rod movement can also be modeled. A special case of columnwise rod movement in a three-dimensional model of a boiling water reactor (BWR) with simple adiabatic feedback is also included. TDTORT is verified through several transient one-dimensional, two-dimensional, and three-dimensional benchmark problems. The results show that the transport methodology and corresponding code developed in this work have sufficient accuracy and speed for computing the dynamic behavior of complex multidimensional neutronic systems

Analysis of Switched-Rigid Floating Oscillator

Directory of Open Access Journals (Sweden)

Prabhakar R. Marur

2009-01-01

Full Text Available In explicit finite element simulations, a technique called deformable-to-rigid (D2R switching is used routinely to reduce the computation time. Using the D2R option, the deformable parts in the model can be switched to rigid and reverted back to deformable when needed during the analysis. The time of activation of D2R however influences the overall dynamics of the system being analyzed. In this paper, a theoretical basis for the selection of time of rigid switching based on system energy is established. A floating oscillator problem is investigated for this purpose and closed-form analytical expressions are derived for different phases in rigid switching. The analytical expressions are validated by comparing the theoretical results with numerical computations.

A control volume scheme for three-dimensional transport: buffer and matrix effect on a decay chain transport in the repository

International Nuclear Information System (INIS)

Lee, Y. M.; Hwang, Y. S.; Kim, S. G.; Kang, C. H.

2002-01-01

Using a three-dimensional numerical code, B3R developed for nuclide transport of an arbitrary length of decay chain in the buffer between the canister and adjacent rock in a high-level radioactive waste repository by adopting a finite difference method utilizing the control-volume scheme, some illustrative calculations have been done. A linear sorption isotherm, nuclide transport due to diffusion in the buffer and the rock matrix, and advection and dispersion along thin rigid parallel fractures existing in a saturated porous rock matrix as well as diffusion through the fracture wall into the matrix is assumed. In such kind of repository, buffer and rock matrix are known to be important physico-chemical barriers in nuclide retardation. To show effects of buffer and rock matrix on nuclide transport in HLW repository and also to demonstrate usefulness of B3R, several cases of breakthrough curves as well as three-dimensional plots of concentration isopleths associated with these two barriers are introduced for a typical case of decay chain of 234 U→ 230 Th→ 226 Ra, which is the most important chain as far as the human environment is concerned

Three-dimensional RAMA fluence methodology benchmarking

International Nuclear Information System (INIS)

Baker, S. P.; Carter, R. G.; Watkins, K. E.; Jones, D. B.

2004-01-01

This paper describes the benchmarking of the RAMA Fluence Methodology software, that has been performed in accordance with U. S. Nuclear Regulatory Commission Regulatory Guide 1.190. The RAMA Fluence Methodology has been developed by TransWare Enterprises Inc. through funding provided by the Electric Power Research Inst., Inc. (EPRI) and the Boiling Water Reactor Vessel and Internals Project (BWRVIP). The purpose of the software is to provide an accurate method for calculating neutron fluence in BWR pressure vessels and internal components. The Methodology incorporates a three-dimensional deterministic transport solution with flexible arbitrary geometry representation of reactor system components, previously available only with Monte Carlo solution techniques. Benchmarking was performed on measurements obtained from three standard benchmark problems which include the Pool Criticality Assembly (PCA), VENUS-3, and H. B. Robinson Unit 2 benchmarks, and on flux wire measurements obtained from two BWR nuclear plants. The calculated to measured (C/M) ratios range from 0.93 to 1.04 demonstrating the accuracy of the RAMA Fluence Methodology in predicting neutron flux, fluence, and dosimetry activation. (authors)

Summary of three-dimensional animation creation based on ethnic culture element

Directory of Open Access Journals (Sweden)

Shao Zhaopo

2016-01-01

Full Text Available three-dimensional animation is a product combined by technology and art. It is an artistic ex-pression form combining painting, film & television, digital technology, music, and literature. As an audio and visual art, three-dimensional animation has its own unique culture-loading function, technical aesthetic charac-teristics, and requirements for national art expression. This paper aims to find the method to combine digital technology and national art in combination of three-dimensional animation short film creation, and hopes to clear the road for the cultivation of domestic three-dimensional animation quality project.

Three-dimensional spiral CT during arterial portography: comparison of three rendering techniques.

Science.gov (United States)

Heath, D G; Soyer, P A; Kuszyk, B S; Bliss, D F; Calhoun, P S; Bluemke, D A; Choti, M A; Fishman, E K

1995-07-01

The three most common techniques for three-dimensional reconstruction are surface rendering, maximum-intensity projection (MIP), and volume rendering. Surface-rendering algorithms model objects as collections of geometric primitives that are displayed with surface shading. The MIP algorithm renders an image by selecting the voxel with the maximum intensity signal along a line extended from the viewer's eye through the data volume. Volume-rendering algorithms sum the weighted contributions of all voxels along the line. Each technique has advantages and shortcomings that must be considered during selection of one for a specific clinical problem and during interpretation of the resulting images. With surface rendering, sharp-edged, clear three-dimensional reconstruction can be completed on modest computer systems; however, overlapping structures cannot be visualized and artifacts are a problem. MIP is computationally a fast technique, but it does not allow depiction of overlapping structures, and its images are three-dimensionally ambiguous unless depth cues are provided. Both surface rendering and MIP use less than 10% of the image data. In contrast, volume rendering uses nearly all of the data, allows demonstration of overlapping structures, and engenders few artifacts, but it requires substantially more computer power than the other techniques.

CFD Simulation of rigid venting of the containment of a BWR-5 Mark-II reactor

International Nuclear Information System (INIS)

Galindo G, I. F.; Vazquez B, A. K.; Velazquez E, L.; Tijerina S, F.; Tapia M, R.

2016-09-01

In conditions of prolonged loss of external energy or a severe accident, venting to the atmosphere is an alternative to prevent overpressure and release of fission products from the primary containment of a nuclear reactor. Due to the importance of flow determination through rigid vents, a computational fluid dynamics (CFD) model is proposed to verify the capacity of rigid vents in the primary containment of a boiling water reactor (BWR) under different operating conditions (pressure, temperature and compositions of the fluids). The model predicts and provides detailed information on variables such as mass flow and velocity of the venting gases. In the proposed model the primary containment gas is vented to the atmosphere via rigid vents (pipes) from the dry and wet pit. Is assumed that the container is pressurized because is in a defined scenario, and at one point the venting is open and the gas released into the atmosphere. The objective is to characterize the flow and validate the CFD model for the overpressure conditions that occur in an accident such as a LOCA, Sbo, etc. The model is implemented with Ansys-Fluent general-purpose CFD software based on the geometry of the venting ducts of the containment of a BWR. The model is developed three-dimensional and resolves at steady state for compressible flow and includes the effects of the turbulence represented by the Reynolds stress model. The CFD results are compared with the values of a one-dimensional and isentropic model for compressible flow. The relative similarity of results leads to the conclusion that the proposed CFD model can help to predict the rigid venting capacity of the containment of a BWR, however more information is required for full validation of the proposed model. (Author)

Three-dimensional reconstruction of the pigeon inner ear

NARCIS (Netherlands)

Hofman, R.; Segenhout, J. M.; Wit, H. P.

2009-01-01

Three-dimensional reconstructions of the inner ear of the pigeon (Columba livia domestica), from two-dimensional images, obtained with (conventional) light microscopy or orthogonal-plane fluorescence optical sectioning (OPFOS), are presented. The results are compared with available information on

A Soft Gripper with Rigidity Tunable Elastomer Strips as Ligaments.

Science.gov (United States)

Nasab, Amir Mohammadi; Sabzehzar, Amin; Tatari, Milad; Majidi, Carmel; Shan, Wanliang

2017-12-01

Like their natural counterparts, soft bioinspired robots capable of actively tuning their mechanical rigidity can rapidly transition between a broad range of motor tasks-from lifting heavy loads to dexterous manipulation of delicate objects. Reversible rigidity tuning also enables soft robot actuators to reroute their internal loading and alter their mode of deformation in response to intrinsic activation. In this study, we demonstrate this principle with a three-fingered pneumatic gripper that contains "programmable" ligaments that change stiffness when activated with electrical current. The ligaments are composed of a conductive, thermoplastic elastomer composite that reversibly softens under resistive heating. Depending on which ligaments are activated, the gripper will bend inward to pick up an object, bend laterally to twist it, and bend outward to release it. All of the gripper motions are generated with a single pneumatic source of pressure. An activation-deactivation cycle can be completed within 15 s. The ability to incorporate electrically programmable ligaments in a pneumatic or hydraulic actuator has the potential to enhance versatility and reduce dependency on tubing and valves.

Encountered-Type Haptic Interface for Representation of Shape and Rigidity of 3D Virtual Objects.

Science.gov (United States)

Takizawa, Naoki; Yano, Hiroaki; Iwata, Hiroo; Oshiro, Yukio; Ohkohchi, Nobuhiro

2017-01-01

This paper describes the development of an encountered-type haptic interface that can generate the physical characteristics, such as shape and rigidity, of three-dimensional (3D) virtual objects using an array of newly developed non-expandable balloons. To alter the rigidity of each non-expandable balloon, the volume of air in it is controlled through a linear actuator and a pressure sensor based on Hooke's law. Furthermore, to change the volume of each balloon, its exposed surface area is controlled by using another linear actuator with a trumpet-shaped tube. A position control mechanism is constructed to display virtual objects using the balloons. The 3D position of each balloon is controlled using a flexible tube and a string. The performance of the system is tested and the results confirm the effectiveness of the proposed principle and interface.

Surface representations of two- and three-dimensional fluid flow topology

Science.gov (United States)

Helman, James L.; Hesselink, Lambertus

1990-01-01

We discuss our work using critical point analysis to generate representations of the vector field topology of numerical flow data sets. Critical points are located and characterized in a two-dimensional domain, which may be either a two-dimensional flow field or the tangential velocity field near a three-dimensional body. Tangent curves are then integrated out along the principal directions of certain classes of critical points. The points and curves are linked to form a skeleton representing the two-dimensional vector field topology. When generated from the tangential velocity field near a body in a three-dimensional flow, the skeleton includes the critical points and curves which provide a basis for analyzing the three-dimensional structure of the flow separation. The points along the separation curves in the skeleton are used to start tangent curve integrations to generate surfaces representing the topology of the associated flow separations.

Three-dimensional magnetophotonic crystals based on artificial opals

Science.gov (United States)

Baryshev, A. V.; Kodama, T.; Nishimura, K.; Uchida, H.; Inoue, M.

2004-06-01

We fabricated and experimentally investigated three-dimensional magnetophotonic crystals (3D MPCs) based on artificial opals. Opal samples with three-dimensional dielectric lattices were impregnated with different types of magnetic material. Magnetic and structural properties of 3D MPCs were studied by field emission scanning electron microscopy, x-ray diffraction analysis, and vibrating sample magnetometer. We have shown that magnetic materials synthesized in voids of opal lattices and the composites obtained have typical magnetic properties.

Three-dimensional magnetophotonic crystals based on artificial opals

International Nuclear Information System (INIS)

Baryshev, A.V.; Kodama, T.; Nishimura, K.; Uchida, H.; Inoue, M.

2004-01-01

We fabricated and experimentally investigated three-dimensional magnetophotonic crystals (3D MPCs) based on artificial opals. Opal samples with three-dimensional dielectric lattices were impregnated with different types of magnetic material. Magnetic and structural properties of 3D MPCs were studied by field emission scanning electron microscopy, x-ray diffraction analysis, and vibrating sample magnetometer. We have shown that magnetic materials synthesized in voids of opal lattices and the composites obtained have typical magnetic properties

THREE-DIMENSIONAL DOPPLER TOMOGRAPHY OF THE RS VULPECULAE INTERACTING BINARY

International Nuclear Information System (INIS)

Richards, Mercedes T.; Sharova, Olga I.; Agafonov, Michail I.

2010-01-01

Three-dimensional Doppler tomography has been used to study the Hα emission sources in the RS Vulpeculae (RS Vul) interacting binary. The two-dimensional tomogram of this binary suggested that most of the emission arises from the cool mass losing star with additional evidence of a gas stream flowing close to its predicted trajectory. However, the three-dimensional tomogram revealed surprising evidence that the gas stream has an average velocity of -85 km s -1 relative to the central velocity plane at V z = 0 km s -1 , unlike U CrB in which the stream was prominent along this central plane. These unexpected V z motions may result from the interaction between magnetic activity on the cool star and the gravitationally induced Roche lobe overflow from that star. Evidence of a loop prominence on the cool star close to the L1 point has been found in the three-dimensional tomogram of RS Vul; hence, the magnetic field lines may have deflected the gas stream relative to the central plane. This result is consistent with earlier detections of RS Vul as both an X-ray and a radio source, and represents the first detection of a loop prominence in an interacting binary based on tomography. Moreover, recent radio images of β Per, the prototype of the Algols, show that the magnetic field of the mass losing star is asymmetric and extends well beyond the orbital plane of the binary, so it is now plausible that the gas flow between the stars in RS Vul could be deflected in an asymmetric way by the magnetic field.

Possibility of estimating three-dimensional mandibular morphology by cephalogram analysis

International Nuclear Information System (INIS)

Kim, S.; Motegi, Etsuko; Kikuchi, Yu; Yamaguchi, Hideharu; Takaki, Takashi; Shibahara, Takahiko

2007-01-01

The purpose of this study was to investigate the possibility of a surmise of three-dimensional mandibular morphology by two-dimensional cephalogram analysis. The materials were three-dimensional CT and cephalogram of 20 female mandibular prognathism patients (average age: 25.20±7.49) before there orthognathic surgery. Mandibular bone volume and sponge bone width were calculated from three-dimensional images constructed from CT images using imaging software (Real Intage, KGT inc.). There was a positive correlation (r=0.72) between mandibular volume value and mandibular ramus width. There was a positive correlation between sponge bone width at the site of the mandibular cuspid and mandibular ramus width and SNB angle (r=0.80), and between sponge bone width at the site of the mandibular molar and symphysis height and mandibular ramus width (r=0.81). It was thought that these results will be useful for a surmise of three-dimensional mandibular morphology by cephalogram analysis. (author)

Three-dimensional interpretation of TEM soundings

Science.gov (United States)

Barsukov, P. O.; Fainberg, E. B.

2013-07-01

We describe the approach to the interpretation of electromagnetic (EM) sounding data which iteratively adjusts the three-dimensional (3D) model of the environment by local one-dimensional (1D) transformations and inversions and reconstructs the geometrical skeleton of the model. The final 3D inversion is carried out with the minimal number of the sought parameters. At each step of the interpretation, the model of the medium is corrected according to the geological information. The practical examples of the suggested method are presented.

A three-dimensional computational model of collagen network mechanics.

Directory of Open Access Journals (Sweden)

Byoungkoo Lee

Full Text Available Extracellular matrix (ECM strongly influences cellular behaviors, including cell proliferation, adhesion, and particularly migration. In cancer, the rigidity of the stromal collagen environment is thought to control tumor aggressiveness, and collagen alignment has been linked to tumor cell invasion. While the mechanical properties of collagen at both the single fiber scale and the bulk gel scale are quite well studied, how the fiber network responds to local stress or deformation, both structurally and mechanically, is poorly understood. This intermediate scale knowledge is important to understanding cell-ECM interactions and is the focus of this study. We have developed a three-dimensional elastic collagen fiber network model (bead-and-spring model and studied fiber network behaviors for various biophysical conditions: collagen density, crosslinker strength, crosslinker density, and fiber orientation (random vs. prealigned. We found the best-fit crosslinker parameter values using shear simulation tests in a small strain region. Using this calibrated collagen model, we simulated both shear and tensile tests in a large linear strain region for different network geometry conditions. The results suggest that network geometry is a key determinant of the mechanical properties of the fiber network. We further demonstrated how the fiber network structure and mechanics evolves with a local formation, mimicking the effect of pulling by a pseudopod during cell migration. Our computational fiber network model is a step toward a full biomechanical model of cellular behaviors in various ECM conditions.

Three-dimensional teletherapy treatment planning

International Nuclear Information System (INIS)

Panthaleon van Eck, R.B. van.

1986-01-01

This thesis deals with physical/mathematical backgrounds of computerized teletherapy treatment planning. The subjects discussed in this thesis can be subdivided into three main categories: a) Three-dimensional treatment planning. A method is evaluated which can be used for the purpose of simulation and optimization of dose distributions in three dimensions. b) The use of Computed Tomography. The use of patient information obtained from Computed Tomography for the purpose of dose computations is evaluated. c) Dose computational models for photon- and electron beams. Models are evaluated which provide information regarding the way in which the radiation dose is distributed in the patient (viz. is absorbed and/or dispersed). (Auth.)

Three-dimensional imaging technology offers promise in medicine.

Science.gov (United States)

Karako, Kenji; Wu, Qiong; Gao, Jianjun

2014-04-01

Medical imaging plays an increasingly important role in the diagnosis and treatment of disease. Currently, medical equipment mainly has two-dimensional (2D) imaging systems. Although this conventional imaging largely satisfies clinical requirements, it cannot depict pathologic changes in 3 dimensions. The development of three-dimensional (3D) imaging technology has encouraged advances in medical imaging. Three-dimensional imaging technology offers doctors much more information on a pathology than 2D imaging, thus significantly improving diagnostic capability and the quality of treatment. Moreover, the combination of 3D imaging with augmented reality significantly improves surgical navigation process. The advantages of 3D imaging technology have made it an important component of technological progress in the field of medical imaging.

Nitrogen-Doped Three Dimensional Graphene for Electrochemical Sensing.

Science.gov (United States)

Yan, Jing; Chen, Ruwen; Liang, Qionglin; Li, Jinghong

2015-07-01

The rational assembly and doping of graphene play an crucial role in the improvement of electrochemical performance for analytical applications. Covalent assembly of graphene into ordered hierarchical structure provides an interconnected three dimensional conductive network and large specific area beneficial to electrolyte transfer on the electrode surface. Chemical doping with heteroatom is a powerful tool to intrinsically modify the electronic properties of graphene due to the increased free charge-carrier densities. By incorporating covalent assembly and nitrogen doping strategy, a novel nitrogen doped three dimensional reduced graphene oxide nanostructure (3D-N-RGO) was developed with synergetic enhancement in electrochemical behaviors. The as prepared 3D-N-RGO was further applied for catechol detection by differential pulse voltammetry. It exhibits much higher electrocatalytic activity towards catechol with increased peak current and decreased potential difference between the oxidation and reduction peaks. Owing to the improved electro-chemical properties, the response of the electrochemical sensor varies linearly with the catechol concentrations ranging from 5 µM to 100 µM with a detection limit of 2 µM (S/N = 3). This work is promising to open new possibilities in the study of novel graphene nanostructure and promote its potential electrochemical applications.

Three-dimensional S-wave tomography under Axial Seamount

Science.gov (United States)

Baillard, C.; Wilcock, W. S. D.; Arnulf, A. F.; Tolstoy, M.; Waldhauser, F.

2017-12-01

Axial Seamount is a submarine volcano located at the intersection of the Juande Fuca Ridge and the Cobb-Eickelberg hotspot 500 km off the coast of thenorthwestern United States. The seamount, which rises 1 km above the seafloor, ischaracterized by a shallow caldera that is elongated in the N-S direction, measure 8km by 3 km and sits on top of a 14 km by 3 km magma reservoir. Two eruptive eventsin 1998 and 2011 motivated the deployment in 2014 of a real time cabled observatorywithin the Axial caldera, as part of the Ocean Observatories Initiative (OOI).Theobservatory includes a network of seven seismometers that span the southern half ofthe caldera. Five months after the observatory came on-line in November 2014, thevolcano erupted on April 24, 2015. Well over 100,000 events were located in thevicinity of the caldera, delineating an outward dipping ring fault that extends fromnear the surface to the magma body at 2 km depth and which accommodatesinflation and deflation of the volcano.The initial earthquake locations have beenobtained with a one-dimensional velocity model but the travel time residuals suggeststrong heterogeneities. A three-dimensional P-wave velocity model, obtained bycombining multichannel and ocean bottom seismometer refraction data, is being usedto refine locations but the three-dimensional S-wave structure is presently unknown.In most mid-ocean ridge settings, the distribution of earthquakes is not conducive forjoint inversions for S-wave velocity and hypocentral parameters because there are fewcrossing ray paths but at Axial the presence of a ring fault that is seismically active atall depths on both the east and west side of the caldera, provides a reasonablegeometry for such efforts. We will present the results of joint inversions that assumethe existing three-dimensional P wave velocity model and solve for VP/VS structure andhypocentral parameters using LOTOS, an algorithm that solves the forward problemusing ray bending.The resulting model

Three-dimensional echocardiographic assessment of the repaired mitral valve.

Science.gov (United States)

Maslow, Andrew; Mahmood, Feroze; Poppas, Athena; Singh, Arun

2014-02-01

This study examined the geometric changes of the mitral valve (MV) after repair using conventional and three-dimensional echocardiography. Prospective evaluation of consecutive patients undergoing mitral valve repair. Tertiary care university hospital. Fifty consecutive patients scheduled for elective repair of the mitral valve for regurgitant disease. Intraoperative transesophageal echocardiography. Assessments of valve area (MVA) were performed using two-dimensional planimetry (2D-Plan), pressure half-time (PHT), and three-dimensional planimetry (3D-Plan). In addition, the direction of ventricular inflow was assessed from the three-dimensional imaging. Good correlations (r = 0.83) and agreement (-0.08 +/- 0.43 cm(2)) were seen between the MVA measured with 3D-Plan and PHT, and were better than either compared to 2D-Plan. MVAs were smaller after repair of functional disease repaired with an annuloplasty ring. After repair, ventricular inflow was directed toward the lateral ventricular wall. Subgroup analysis showed that the change in inflow angle was not different after repair of functional disease (168 to 171 degrees) as compared to those presenting with degenerative disease (168 to 148 degrees; p<0.0001). Three-dimensional imaging provides caregivers with a unique ability to assess changes in valve function after mitral valve repair. Copyright © 2014 Elsevier Inc. All rights reserved.

Tactical Routing Using Two-Dimensional and Three-Dimensional Views of Terrain

National Research Council Canada - National Science Library

St

2001-01-01

Consoles for military and civilian occupations such as air warfare, command and control, air traffic control, piloting, and meteorological forecasting will be capable of displaying three-dimensional (3-D) perspective views...

Three-dimensional strutted graphene grown by substrate-free sugar blowing for high-power-density supercapacitors

Science.gov (United States)

Wang, Xuebin; Zhang, Yuanjian; Zhi, Chunyi; Wang, Xi; Tang, Daiming; Xu, Yibin; Weng, Qunhong; Jiang, Xiangfen; Mitome, Masanori; Golberg, Dmitri; Bando, Yoshio

2013-12-01

Three-dimensional graphene architectures in the macroworld can in principle maintain all the extraordinary nanoscale properties of individual graphene flakes. However, current 3D graphene products suffer from poor electrical conductivity, low surface area and insufficient mechanical strength/elasticity; the interconnected self-supported reproducible 3D graphenes remain unavailable. Here we report a sugar-blowing approach based on a polymeric predecessor to synthesize a 3D graphene bubble network. The bubble network consists of mono- or few-layered graphitic membranes that are tightly glued, rigidly fixed and spatially scaffolded by micrometre-scale graphitic struts. Such a topological configuration provides intimate structural interconnectivities, freeway for electron/phonon transports, huge accessible surface area, as well as robust mechanical properties. The graphene network thus overcomes the drawbacks of presently available 3D graphene products and opens up a wide horizon for diverse practical usages, for example, high-power high-energy electrochemical capacitors, as highlighted in this work.

Three-dimensional strutted graphene grown by substrate-free sugar blowing for high-power-density supercapacitors

Science.gov (United States)

Wang, Xuebin; Zhang, Yuanjian; Zhi, Chunyi; Wang, Xi; Tang, Daiming; Xu, Yibin; Weng, Qunhong; Jiang, Xiangfen; Mitome, Masanori; Golberg, Dmitri; Bando, Yoshio

2013-01-01

Three-dimensional graphene architectures in the macroworld can in principle maintain all the extraordinary nanoscale properties of individual graphene flakes. However, current 3D graphene products suffer from poor electrical conductivity, low surface area and insufficient mechanical strength/elasticity; the interconnected self-supported reproducible 3D graphenes remain unavailable. Here we report a sugar-blowing approach based on a polymeric predecessor to synthesize a 3D graphene bubble network. The bubble network consists of mono- or few-layered graphitic membranes that are tightly glued, rigidly fixed and spatially scaffolded by micrometre-scale graphitic struts. Such a topological configuration provides intimate structural interconnectivities, freeway for electron/phonon transports, huge accessible surface area, as well as robust mechanical properties. The graphene network thus overcomes the drawbacks of presently available 3D graphene products and opens up a wide horizon for diverse practical usages, for example, high-power high-energy electrochemical capacitors, as highlighted in this work. PMID:24336225

Three dimensional peristaltic flow of hyperbolic tangent fluid in non-uniform channel having flexible walls

Directory of Open Access Journals (Sweden)

M. Ali Abbas

2016-03-01

Full Text Available In this present analysis, three dimensional peristaltic flow of hyperbolic tangent fluid in a non-uniform channel has been investigated. We have considered that the pressure is uniform over the whole cross section and the interial effects have been neglected. For this purpose we consider laminar flow under the assumptions of long wavelength (λ→∞ and creeping flow (Re→0 approximations. The attained highly nonlinear equations are solved with the help of Homotopy perturbation method. The influence of various physical parameters of interest is demonstrated graphically for wall tension, mass characterization, damping nature of the wall, wall rigidity, wall elastance, aspect ratio and the Weissenberg number. In this present investigation we found that the magnitude of the velocity is maximum in the center of the channel whereas it is minimum near the walls. Stream lines are also drawn to discuss the trapping mechanism for all the physical parameters. Comparison has also been presented between Newtonian and non-Newtonian fluid.

Crystallization of a self-assembled three-dimensional DNA nanostructure

International Nuclear Information System (INIS)

Rendek, Kimberly N.; Fromme, Raimund; Grotjohann, Ingo; Fromme, Petra

2013-01-01

In this work, the crystallization of a self-assembling three-dimensional B-DNA nanostructure is described. The powerful and specific molecular-recognition system present in the base-pairing of DNA allows for the design of a plethora of nanostructures. In this work, the crystallization of a self-assembling three-dimensional B-DNA nanostructure is described. The DNA nanostructure consists of six single-stranded oligonucleotides that hybridize to form a three-dimensional tetrahedron of 80 kDa in molecular mass and 20 bp on each edge. Crystals of the tetrahedron have been successfully produced and characterized. These crystals may form the basis for an X-ray structure of the tetrahedron in the future. Nucleotide crystallography poses many challenges, leading to the fact that only 1352 X-ray structures of nucleic acids have been solved compared with more than 80 000 protein structures. In this work, the crystallization optimization for three-dimensional tetrahedra is also described, with the eventual goal of producing nanocrystals to overcome the radiation-damage obstacle by the use of free-electron laser technology in the future

Three-dimensional Ag{sub 2}O/WO{sub 3}·0.33H{sub 2}O heterostructures for improving photocatalytic activity

Energy Technology Data Exchange (ETDEWEB)

He, Xiaoyu [Department of Applied Physics, Chongqing University, Chongqing 400044 (China); Department of Physics and Electronic Engineering, Yangtze Normal University, Chongqing 408100 (China); Hu, Chenguo, E-mail: hucg@cqu.edu.cn [Department of Applied Physics, Chongqing University, Chongqing 400044 (China); Xi, Yi; Zhang, Kaiyou; Hua, Hao [Department of Applied Physics, Chongqing University, Chongqing 400044 (China)

2014-02-01

Highlights: • Ag{sub 2}O/WO{sub 3}·0.33H{sub 2}O 3D network heterostructures are prepared via a simple precipitatation method. • Ag{sub 2}O/WO{sub 3}·0.33H{sub 2}O networks exhibit much enhanced photocatalytic activity. • High photocatalytic activity is attributed to its heterostructure and 3D architectures. - Abstract: Three-dimensional Ag{sub 2}O/WO{sub 3}·0.33H{sub 2}O heterostructures were fabricated by loading Ag{sub 2}O nanoparticles on WO{sub 3}·0.33H{sub 2}O 3D networks via a simple chemical precipitation method. The Ag{sub 2}O/WO{sub 3}·0.33H{sub 2}O heterostructures exhibited much enhanced photocatalytic activity for the degradation of methylene blue (MB) under simulated solar light irradiation. The optimal molar ratio of Ag{sub 2}O and WO{sub 3}·0.33H{sub 2}O is 1:2. The outstanding photocatalytic activity of the Ag{sub 2}O/WO{sub 3}·0.33H{sub 2}O can be attributed to its large surface area of the three-dimensional networks, the enhanced sunlight absorption and the prevention of electrons–holes combination from the heterostructures. The experiment result demonstrates that wide band gap semiconductor (WO{sub 3}·0.33H{sub 2}O) modified by narrow band gap metal oxide (Ag{sub 2}O) with 3D architecture will be an effective route to enhance its photocatalytic activity.

Three Dimensional Energy Transmitting Boundary in the Time Domain

Directory of Open Access Journals (Sweden)

Naohiro eNakamura

2015-11-01

Full Text Available Although the energy transmitting boundary is accurate and efficient for the FEM earthquake response analysis, it could be applied in the frequency domain only. In the previous papers, the author proposed an earthquake response analysis method using the time domain energy transmitting boundary for two dimensional problems. In this paper, this technique is expanded for three dimensional problems. The inner field is supposed to be a hexahedron shape and the approximate time domain boundary is explained, first. Next, two dimensional anti-plane time domain boundary is studied for a part of the approximate three dimensional boundary method. Then, accuracy and efficiency of the proposed method are confirmed by example problems.

A method of image improvement in three-dimensional imaging

International Nuclear Information System (INIS)

Suto, Yasuzo; Huang, Tewen; Furuhata, Kentaro; Uchino, Masafumi.

1988-01-01

In general, image interpolation is required when the surface configurations of such structures as bones and organs are three-dimensionally constructed from the multi-sliced images obtained by CT. Image interpolation is a processing method whereby an artificial image is inserted between two adjacent slices to make spatial resolution equal to slice resolution in appearance. Such image interpolation makes it possible to increase the image quality of the constructed three-dimensional image. In our newly-developed algorithm, we have converted the presently and subsequently sliced images to distance images, and generated the interpolation images from these two distance images. As a result, compared with the previous method, three-dimensional images with better image quality have been constructed. (author)

Usefulness Of Three-Dimensional Printing Models for Patients with Stoma Construction

Directory of Open Access Journals (Sweden)

Tetsuro Tominaga

2016-04-01

Full Text Available The use of patient-specific organ models in three-dimensional printing systems could be helpful for the education of patients and medical students. The aim of this study was to clarify whether the use of patient-specific stoma models is helpful for patient education. From January 2014 to September 2014, 5 patients who underwent colorectal surgery and for whom a temporary or permanent stoma had been created were involved in this study. Three-dimensional stoma models and three-dimensional face plates were created. The patients’ ages ranged from 59 to 81 years. Four patients underwent stoma construction because of rectal cancer, and 1 underwent stoma construction because of colon stenosis secondary to recurrent cancer. All patients were educated about their stoma and potential stoma-associated problems using three-dimensional stoma models, and all practiced cutting face plates using three-dimensional face plates. The models were also used during medical staff conferences to discuss current issues. All patients understood their problems and finally became self-reliant. The recent availability of three-dimensional printers has enabled the creation of many organ models, and full-scale stoma and face plate models are now available for patient education on cutting an appropriately individualized face plate. Thus, three-dimensional printers could enable fewer skin problems than are currently associated with daily stomal care.

Discrete-to-continuum modelling of weakly interacting incommensurate two-dimensional lattices.

Science.gov (United States)

Español, Malena I; Golovaty, Dmitry; Wilber, J Patrick

2018-01-01

In this paper, we derive a continuum variational model for a two-dimensional deformable lattice of atoms interacting with a two-dimensional rigid lattice. The starting point is a discrete atomistic model for the two lattices which are assumed to have slightly different lattice parameters and, possibly, a small relative rotation. This is a prototypical example of a three-dimensional system consisting of a graphene sheet suspended over a substrate. We use a discrete-to-continuum procedure to obtain the continuum model which recovers both qualitatively and quantitatively the behaviour observed in the corresponding discrete model. The continuum model predicts that the deformable lattice develops a network of domain walls characterized by large shearing, stretching and bending deformation that accommodates the misalignment and/or mismatch between the deformable and rigid lattices. Two integer-valued parameters, which can be identified with the components of a Burgers vector, describe the mismatch between the lattices and determine the geometry and the details of the deformation associated with the domain walls.

A Three-Dimensional Object Orientation Detector Assisting People with Developmental Disabilities to Control Their Environmental Stimulation through Simple Occupational Activities with a Nintendo Wii Remote Controller

Science.gov (United States)

Shih, Ching-Hsiang; Chang, Man-Ling; Mohua, Zhang

2012-01-01

This study evaluated whether two people with developmental disabilities would be able to actively perform simple occupational activities to control their preferred environmental stimulation using a Nintendo Wii Remote Controller with a newly developed three-dimensional object orientation detection program (TDOODP, i.e. a new software program,…

Three-dimensional ultrasound strain imaging of skeletal muscles

NARCIS (Netherlands)

Gijsbertse, Kaj; Sprengers, Andre M.; Nillesen, Maartje; Hansen, Hendrik H.G.; Verdonschot, Nico; De Korte, Chris L.

2015-01-01

Muscle contraction is characterized by large deformation and translation, which requires a multi-dimensional imaging modality to reveal its behavior. Previous work on ultrasound strain imaging of the muscle contraction was limited to 2D and bi-plane techniques. In this study, a three-dimensional

Exact solutions in three-dimensional gravity

CERN Document Server

Garcia-Diaz, Alberto A

2017-01-01

A self-contained text, systematically presenting the determination and classification of exact solutions in three-dimensional Einstein gravity. This book explores the theoretical framework and general physical and geometrical characteristics of each class of solutions, and includes information on the researchers responsible for their discovery. Beginning with the physical character of the solutions, these are identified and ordered on the basis of their geometrical invariant properties, symmetries, and algebraic classifications, or from the standpoint of their physical nature, for example electrodynamic fields, fluid, scalar field, or dilaton. Consequently, this text serves as a thorough catalogue on 2+1 exact solutions to the Einstein equations coupled to matter and fields, and on vacuum solutions of topologically massive gravity with a cosmological constant. The solutions are also examined from different perspectives, enabling a conceptual bridge between exact solutions of three- and four-dimensional gravit...

A stereotactic method for the three-dimensional registration of multi-modality biologic images in animals: NMR, PET, histology, and autoradiography

International Nuclear Information System (INIS)

Humm, J.L.; Ballon, D.; Hu, Y.C.; Ruan, S.; Chui, C.; Tulipano, P.K.; Erdi, A.; Koutcher, J.; Zakian, K.; Urano, M.; Zanzonico, P.; Mattis, C.; Dyke, J.; Chen, Y.; Harrington, P.; O'Donoghue, J.A.; Ling, C.C.

2003-01-01

The objective of this work was to develop and then validate a stereotactic fiduciary marker system for tumor xenografts in rodents which could be used to co-register magnetic resonance imaging (MRI), PET, tissue histology, autoradiography, and measurements from physiologic probes. A Teflon TM fiduciary template has been designed which allows the precise insertion of small hollow Teflon rods (0.71 mm diameter) into a tumor. These rods can be visualized by MRI and PET as well as by histology and autoradiography on tissue sections. The methodology has been applied and tested on a rigid phantom, on tissue phantom material, and finally on tumor bearing mice. Image registration has been performed between the MRI and PET images for the rigid Teflon phantom and among MRI, digitized microscopy images of tissue histology, and autoradiograms for both tissue phantom and tumor-bearing mice. A registration accuracy, expressed as the average Euclidean distance between the centers of three fiduciary markers among the registered image sets, of 0.2±0.06 mm was achieved between MRI and microPET image sets of a rigid Teflon phantom. The fiduciary template allows digitized tissue sections to be co-registered with three-dimensional MRI images with an average accuracy of 0.21 and 0.25 mm for the tissue phantoms and tumor xenografts, respectively. Between histology and autoradiograms, it was 0.19 and 0.21 mm for tissue phantoms and tumor xenografts, respectively. The fiduciary marker system provides a coordinate system with which to correlate information from multiple image types, on a voxel-by-voxel basis, with sub-millimeter accuracy--even among imaging modalities with widely disparate spatial resolution and in the absence of identifiable anatomic landmarks

A new background distribution-based active contour model for three-dimensional lesion segmentation in breast DCE-MRI

Energy Technology Data Exchange (ETDEWEB)

Liu, Hui; Liu, Yiping; Qiu, Tianshuang [Department of Biomedical Engineering, Dalian University of Technology, Dalian 116024 (China); Zhao, Zuowei, E-mail: liuhui@dlut.edu.cn [Second Affiliated Hospital, Dalian Medical University, Dalian 116027 (China); Zhang, Lina [Department of Radiology, First Affiliated Hospital, Dalian Medical University, Dalian 116027 (China)

2014-08-15

Purpose: To develop and evaluate a computerized semiautomatic segmentation method for accurate extraction of three-dimensional lesions from dynamic contrast-enhanced magnetic resonance images (DCE-MRIs) of the breast. Methods: The authors propose a new background distribution-based active contour model using level set (BDACMLS) to segment lesions in breast DCE-MRIs. The method starts with manual selection of a region of interest (ROI) that contains the entire lesion in a single slice where the lesion is enhanced. Then the lesion volume from the volume data of interest, which is captured automatically, is separated. The core idea of BDACMLS is a new signed pressure function which is based solely on the intensity distribution combined with pathophysiological basis. To compare the algorithm results, two experienced radiologists delineated all lesions jointly to obtain the ground truth. In addition, results generated by other different methods based on level set (LS) are also compared with the authors’ method. Finally, the performance of the proposed method is evaluated by several region-based metrics such as the overlap ratio. Results: Forty-two studies with 46 lesions that contain 29 benign and 17 malignant lesions are evaluated. The dataset includes various typical pathologies of the breast such as invasive ductal carcinoma, ductal carcinomain situ, scar carcinoma, phyllodes tumor, breast cysts, fibroadenoma, etc. The overlap ratio for BDACMLS with respect to manual segmentation is 79.55% ± 12.60% (mean ± s.d.). Conclusions: A new active contour model method has been developed and shown to successfully segment breast DCE-MRI three-dimensional lesions. The results from this model correspond more closely to manual segmentation, solve the weak-edge-passed problem, and improve the robustness in segmenting different lesions.

Reversible Rigidity Control Using Low Melting Temperature Alloys

Science.gov (United States)

Shan, Wanliang; Lu, Tong; Majidi, Carmel

2013-03-01

Inspired by nature, materials able to achieve rapid rigidity changes have important applications for human body protection in military and many other areas. This talk presents the fabrication and design of soft-matter technologies that exhibit rapid reversible rigidity control. Fabricated with a masked deposition technique, the soft-matter composite contains liquid-phase and phase-changing metal alloys embedded in a soft and highly stretchable elastomer. The composite material can reversibly change its rigidity by three orders of magnitude and sustain large deformation.

Rigidity of complete noncompact bach-flat n-manifolds

Science.gov (United States)

Chu, Yawei; Feng, Pinghua

2012-11-01

Let (Mn,g) be a complete noncompact Bach-flat n-manifold with the positive Yamabe constant and constant scalar curvature. Assume that the L2-norm of the trace-free Riemannian curvature tensor R∘m is finite. In this paper, we prove that (Mn,g) is a constant curvature space if the L-norm of R∘m is sufficiently small. Moreover, we get a gap theorem for (Mn,g) with positive scalar curvature. This can be viewed as a generalization of our earlier results of 4-dimensional Bach-flat manifolds with constant scalar curvature R≥0 [Y.W. Chu, A rigidity theorem for complete noncompact Bach-flat manifolds, J. Geom. Phys. 61 (2011) 516-521]. Furthermore, when n>9, we derive a rigidity result for R<0.

Three-dimensional reacting shock–bubble interaction

NARCIS (Netherlands)

Diegelmann, Felix; Hickel, S.; Adams, Nikolaus A.

2017-01-01

We investigate a reacting shock–bubble interaction through three-dimensional numerical simulations with detailed chemistry. The convex shape of the bubble focuses the shock and generates regions of high pressure and temperature, which are sufficient to ignite the diluted stoichiometric

Collapse in a forced three-dimensional nonlinear Schrodinger equation

DEFF Research Database (Denmark)

Lushnikov, P.M.; Saffman, M.

2000-01-01

We derive sufficient conditions for the occurrence of collapse in a forced three-dimensional nonlinear Schrodinger equation without dissipation. Numerical studies continue the results to the case of finite dissipation.......We derive sufficient conditions for the occurrence of collapse in a forced three-dimensional nonlinear Schrodinger equation without dissipation. Numerical studies continue the results to the case of finite dissipation....

Eustachian tube three-dimensional reconstruction of secretory otitis media

International Nuclear Information System (INIS)

Yu Yafeng; Zhou Weirong; Bao Xueping; Li Min; Hu Zhenmin

2006-01-01

Objective: To study relationship between Eustachian tube and secretory otitis media and to explore the pathogeny of secretory otitis by three-dimensional reconstruction of Eustachian tube. Methods: Thirty cases of secretory otitis media (male 19, female 11) were selected randomly. Everyone was checked by otoscope and audiometry. Their bilateral Eustachian tubes were scanning by helix CT while making Valsalva's action. All images were passed on to work station to make three-dimensional reconstruction. Results: Four patients were found have Eustachian tube diseases, while most of patients' Eustachian tubes ventilated normally. Conclusions: Three-dimensional reconstruction of Eustachian tube can open out some pathogens of some secretory otitis medias. It will be helpful to diagnosis and therapy of secretory otitis media. (authors)

Computerized three-dimensional normal atlas

International Nuclear Information System (INIS)

Mano, Isamu; Suto, Yasuzo; Suzuki, Masataka; Iio, Masahiro.

1990-01-01

This paper presents our ongoing project in which normal human anatomy and its quantitative data are systematically arranged in a computer. The final product, the Computerized Three-Dimensional Normal Atlas, will be able to supply tomographic images in any direction, 3-D images, and coded information on organs, e.g., anatomical names, CT numbers, and T 1 and T 2 values. (author)

Three-Dimensional Shallow Water Acoustics

Science.gov (United States)

2016-03-30

medium properties, so horizontal refraction and reflection of sound can occur and produce significant three-dimensional (3-D) sound propagation ...by the environmental factors existing commonly in the continental shelf and shelfbreak areas, such as slopes, submarine canyons, sub-bottom layers ...surface waves, internal waves and shelfbreak fronts. 15. SUBJECT TERMS Continental Shelf; 3-D Acoustics , Surface Waves, Sound Propagation 16

Three-Dimensional Numerical Modeling of Crustal Growth at Active Continental Margins

Science.gov (United States)

Zhu, G.; Gerya, T.; Tackley, P. J.

2011-12-01

Active margins are important sites of new continental crust formation by magmatic processes related to the subduction of oceanic plates. We investigate these phenomena using a three-dimensional coupled petrological-geochemical-thermomechanical numerical model, which combines a finite-difference flow solver with a non-diffusive marker-in-cell technique for advection (I3ELVIS code, Gerya and Yuen, PEPI,2007). The model includes mantle flow associated with the subducting plate, water release from the slab, fluid propagation that triggers partial melting at the slab surface, melt extraction and the resulting volcanic crustal growth at the surface. The model also accounts for variations in physical properties (mainly density and viscosity) of both fluids and rocks as a function of local conditions in temperature, pressure, deformation, nature of the rocks, and chemical exchanges. Our results show different patterns of crustal growth and surface topography, which are comparable to nature, during subduction at active continental margins. Often, two trench-parallel lines of magmatic activity, which reflect two maxima of melt production atop the slab, are formed on the surface. The melt extraction rate controls the patterns of new crust at different ages. Moving free water reflects the path of fluids, and the velocity of free water shows the trend of two parallel lines of magmatic activity. The formation of new crust in particular time intervals is distributed in finger-like shapes, corresponding to finger-like and ridge-like cold plumes developed atop the subducting slabs (Zhu et al., G-cubed,2009; PEPI,2011). Most of the new crust is basaltic, formed from peridotitic mantle. Granitic crust extracted from melted sediment and upper crust forms in a line closer to the trench, and its distribution reflects the finger-like cold plumes. Dacitic crust extracted from the melted lower crust forms in a line farther away from the trench, and its distribution is anticorrelated with

Three-dimensional quantitative structure-activity relationships and docking studies of some structurally diverse flavonoids and design of new aldose reductase inhibitors

Directory of Open Access Journals (Sweden)

Utpal Chandra De

2015-01-01

Full Text Available Aldose reductase (AR plays an important role in the development of several long-term diabetic complications. Inhibition of AR activities is a strategy for controlling complications arising from chronic diabetes. Several AR inhibitors have been reported in the literature. Flavonoid type compounds are shown to have significant AR inhibition. The objective of this study was to perform a computational work to get an idea about structural insight of flavonoid type compounds for developing as well as for searching new flavonoid based AR inhibitors. The data-set comprising 68 flavones along with their pIC 50 values ranging from 0.44 to 4.59 have been collected from literature. Structure of all the flavonoids were drawn in Chembiodraw Ultra 11.0, converted into corresponding three-dimensional structure, saved as mole file and then imported to maestro project table. Imported ligands were prepared using LigPrep option of maestro 9.6 version. Three-dimensional quantitative structure-activity relationships and docking studies were performed with appropriate options of maestro 9.6 version installed in HP Z820 workstation with CentOS 6.3 (Linux. A model with partial least squares factor 5, standard deviation 0.2482, R 2 = 0.9502 and variance ratio of regression 122 has been found as the best statistical model.

Three dimensional CT imaging of ossicular chain: a preliminary study

International Nuclear Information System (INIS)

Hu Chunhong; Zhong Shenbin; Fu Yindi; Zhu Wei; Wang Xueyuan; Chen Jianhua; Ding Yi

2001-01-01

Objective: To analysis the features of normal and abnormal ossicular chain in three dimensional images and asses the best parameters and its usefulness in diagnosis and treatment of chronic otitis media (COM). Methods: All patients, including 43 patients with normal ears and 24 ears with COM, were examined using spiral CT with inner ear software, 1-mm slice width and 1 pitch. SSD method was used in three dimensional reconstruction and the threshold was 100-300 Hu. Results: In normal cases, Malleus, incus, stapes crura, incudomalleal joints and incudostapedial joints were displayed well, but stapes footplate unsatisfactorily. The disruption of the ossicular chain showed in three-dimensional images in cases of chronic otitis media was in accord with that seen in the operation. Conclusion: It is very important for imaging with high quality through selecting proper parameters, and three-dimensional image can provide valuable information for surgery

Stress distribution in delayed replanted teeth splinted with different orthodontic wires: a three-dimensional finite element analysis.

Science.gov (United States)

de Souza, Fernando Isquierdo; Poi, Wilson Roberto; da Silva, Vanessa Ferreira; Martini, Ana Paula; Melo, Regis Alexandre da Cunha; Panzarini, Sonia Regina; Rocha, Eduardo Passos

2015-06-01

The aim was to evaluate the biomechanical behavior of the supporting bony structures of replanted teeth and the periodontal ligament (PDL) of adjacent teeth when orthodontic wires with different mechanical properties are applied, with three-dimensional finite element analysis. Based on tomographic and microtomographic data, a three-dimensional model of the anterior maxilla with the corresponding teeth (tooth 13-tooth 23) was generated to simulate avulsion and replantation of the tooth 21. The teeth were splinted with orthodontic wire (Ø 0.8 mm) and composite resin. The elastic modulus of the three orthodontic wires used, that is, steel wire (FA), titanium-molybdenum wire (FTM), and nitinol wire (FN) were 200 GPa, 84 GPa, and 52 GPa, respectively. An oblique load (100 N) was applied at an angle of 45° on the incisal edge of the replanted tooth and was analyzed using Ansys Workbench software. The maximum (σmax) and minimum (σmin) principal stresses generated in the PDL, cortical and alveolar bones, and the modified von Mises (σvM) values for the orthodontic wires were obtained. With regard to the cortical bone and PDL, the highest σmin and σmax values for FTM, FN, and FA were checked. With regard to the alveolar bone, σmax and σmin values were highest for FA, followed by FTM and FN. The σvM values of the orthodontic wires followed the order of rigidity of the alloys, that is, FA > FTM > FN. The biomechanical behavior of the analyzed structures with regard to all the three patterns of flexibility was similar. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Rigid cohomology over Laurent series fields

CERN Document Server

Lazda, Christopher

2016-01-01

In this monograph, the authors develop a new theory of p-adic cohomology for varieties over Laurent series fields in positive characteristic, based on Berthelot's theory of rigid cohomology. Many major fundamental properties of these cohomology groups are proven, such as finite dimensionality and cohomological descent, as well as interpretations in terms of Monsky-Washnitzer cohomology and Le Stum's overconvergent site. Applications of this new theory to arithmetic questions, such as l-independence and the weight monodromy conjecture, are also discussed. The construction of these cohomology groups, analogous to the Galois representations associated to varieties over local fields in mixed characteristic, fills a major gap in the study of arithmetic cohomology theories over function fields. By extending the scope of existing methods, the results presented here also serve as a first step towards a more general theory of p-adic cohomology over non-perfect ground fields. Rigid Cohomology over Laurent Series Fields...

Three dimensional digital imaging of environmental data

International Nuclear Information System (INIS)

Nichols, R.L.; Eddy, C.A.

1991-01-01

The Environmental Sciences Section (ESS) of the Savannah River Laboratory has recently acquired the computer hardware (Silicon Graphics Personal Iris Workstations) and software (Dynamic Graphics, Interactive Surface and Volume Modeling) to perform three dimensional analysis of hydrogeologic data. Three dimensional digital imaging of environmental data is a powerful technique that can be used to incorporate field, analytical, and modeling results from geologic, hydrologic, ecologic, and chemical studies into a comprehensive model for visualization and interpretation. This report covers the contamination of four different sites of the Savannah River Plant. Each section of this report has a computer graphic display of the concentration of contamination in the groundwater and/or sediments of each site

Three-dimensional Imaging, Visualization, and Display

CERN Document Server

Javidi, Bahram; Son, Jung-Young

2009-01-01

Three-Dimensional Imaging, Visualization, and Display describes recent developments, as well as the prospects and challenges facing 3D imaging, visualization, and display systems and devices. With the rapid advances in electronics, hardware, and software, 3D imaging techniques can now be implemented with commercially available components and can be used for many applications. This volume discusses the state-of-the-art in 3D display and visualization technologies, including binocular, multi-view, holographic, and image reproduction and capture techniques. It also covers 3D optical systems, 3D display instruments, 3D imaging applications, and details several attractive methods for producing 3D moving pictures. This book integrates the background material with new advances and applications in the field, and the available online supplement will include full color videos of 3D display systems. Three-Dimensional Imaging, Visualization, and Display is suitable for electrical engineers, computer scientists, optical e...

Velocity measurements in a rigid ceramic filter in a parallel-flow arrangement

International Nuclear Information System (INIS)

Al-Hajeri, M.H.; Aroussi, A.; Witry, A.

2002-01-01

Rigid ceramic filters have been developed for cleaning the hot combustion gas streams upstream of the turbine in a combined cycle power plant. To obtain continues operation a periodic cleaning is necessary and the cleaning efficiency depends on the distribution of the filtration cake. Consequently uniform particle deposition on the filter element surface is desired. The flow around three filter elements in cross flow is investigated computationally using the commercial code FLUENT. Three filter elements are placed in a two-dimensional rectangle duct with fixed face velocity and varying the velocity ratio between the approach and face velocity. Particle trajectories are obtained for a number of particle diameters and different inlet (approach) velocity to face filtration velocity ratios to investigate the behavior of particles around the filter element. (author)

Three-dimensional radiation treatment planning

International Nuclear Information System (INIS)

Mohan, R.

1989-01-01

A major aim of radiation therapy is to deliver sufficient dose to the tumour volume to kill the cancer cells while sparing the nearby health organs to prevent complications. With the introduction of devices such as CT and MR scanners, radiation therapy treatment planners have access to full three-dimensional anatomical information to define, simulate, and evaluate treatments. There are a limited number of prototype software systems that allow 3D treatment planning currently in use. In addition, there are more advanced tools under development or still in the planning stages. They require sophisticated graphics and computation equipment, complex physical and mathematical algorithms, and new radiation treatment machines that deliver dose very precisely under computer control. Components of these systems include programs for the identification and delineation of the anatomy and tumour, the definition of radiation beams, the calculation of dose distribution patterns, the display of dose on 2D images and as three dimensional surfaces, and the generation of computer images to verify proper patient positioning in treatment. Some of these functions can be performed more quickly and accurately if artificial intelligence or expert systems techniques are employed. 28 refs., figs

Three-dimensional cooling of muons

CERN Document Server

Vsevolozhskaya, T A

2000-01-01

The simultaneous ionization cooling of muon beams in all three - the longitudinal and two transverse - directions is considered in a scheme, based on bent lithium lenses with dipole constituent of magnetic field in them, created by a special configuration of current-carrying rod. An analysis of three-dimensional cooling is performed with the use of kinetic equation method. Results of numerical calculation for a specific beam line configuration are presented together with results of computer simulation using the Moliere distribution to describe the Coulomb scattering and the Vavilov distribution used to describe the ionization loss of energy.

Vibrational spectra and thermal rectification in three-dimensional anharmonic lattices

International Nuclear Information System (INIS)

Lan Jinghua; Li Baowen

2007-01-01

We study thermal rectification in a three-dimensional model consisting of two segments of anharmonic lattices. One segment consists of layers of harmonic oscillator arrays coupled to a substrate potential, which is a three-dimensional Frenkel-Kontorova model, and the other segment is a three-dimensional Fermi-Pasta-Ulam model. We study the vibrational bands of the two lattices analytically and numerically, and find that, by choosing the system parameters properly, the rectification can be as high as a few thousands, which is high enough to be observed in experiment. Possible experiments in nanostructures are discussed

Characterizing College Science Assessments: The Three-Dimensional Learning Assessment Protocol

Science.gov (United States)

Underwood, Sonia M.; Matz, Rebecca L.; Posey, Lynmarie A.; Carmel, Justin H.; Caballero, Marcos D.; Fata-Hartley, Cori L.; Ebert-May, Diane; Jardeleza, Sarah E.; Cooper, Melanie M.

2016-01-01

Many calls to improve science education in college and university settings have focused on improving instructor pedagogy. Meanwhile, science education at the K-12 level is undergoing significant changes as a result of the emphasis on scientific and engineering practices, crosscutting concepts, and disciplinary core ideas. This framework of “three-dimensional learning” is based on the literature about how people learn science and how we can help students put their knowledge to use. Recently, similar changes are underway in higher education by incorporating three-dimensional learning into college science courses. As these transformations move forward, it will become important to assess three-dimensional learning both to align assessments with the learning environment, and to assess the extent of the transformations. In this paper we introduce the Three-Dimensional Learning Assessment Protocol (3D-LAP), which is designed to characterize and support the development of assessment tasks in biology, chemistry, and physics that align with transformation efforts. We describe the development process used by our interdisciplinary team, discuss the validity and reliability of the protocol, and provide evidence that the protocol can distinguish between assessments that have the potential to elicit evidence of three-dimensional learning and those that do not. PMID:27606671

Characterizing College Science Assessments: The Three-Dimensional Learning Assessment Protocol.

Science.gov (United States)

Laverty, James T; Underwood, Sonia M; Matz, Rebecca L; Posey, Lynmarie A; Carmel, Justin H; Caballero, Marcos D; Fata-Hartley, Cori L; Ebert-May, Diane; Jardeleza, Sarah E; Cooper, Melanie M

2016-01-01

Many calls to improve science education in college and university settings have focused on improving instructor pedagogy. Meanwhile, science education at the K-12 level is undergoing significant changes as a result of the emphasis on scientific and engineering practices, crosscutting concepts, and disciplinary core ideas. This framework of "three-dimensional learning" is based on the literature about how people learn science and how we can help students put their knowledge to use. Recently, similar changes are underway in higher education by incorporating three-dimensional learning into college science courses. As these transformations move forward, it will become important to assess three-dimensional learning both to align assessments with the learning environment, and to assess the extent of the transformations. In this paper we introduce the Three-Dimensional Learning Assessment Protocol (3D-LAP), which is designed to characterize and support the development of assessment tasks in biology, chemistry, and physics that align with transformation efforts. We describe the development process used by our interdisciplinary team, discuss the validity and reliability of the protocol, and provide evidence that the protocol can distinguish between assessments that have the potential to elicit evidence of three-dimensional learning and those that do not.

Three dimensional imaging technique for laser-plasma diagnostics

International Nuclear Information System (INIS)

Jiang Shaoen; Zheng Zhijian; Liu Zhongli

2001-01-01

A CT technique for laser-plasma diagnostic and a three-dimensional (3D) image reconstruction program (CT3D) have been developed. The 3D images of the laser-plasma are reconstructed by using a multiplication algebraic reconstruction technique (MART) from five pinhole camera images obtained along different sight directions. The technique has been used to measure the three-dimensional distribution of X-ray of laser-plasma experiments in Xingguang II device, and the good results are obtained. This shows that a CT technique can be applied to ICF experiments

Three dimensional imaging technique for laser-plasma diagnostics

Energy Technology Data Exchange (ETDEWEB)

Shaoen, Jiang; Zhijian, Zheng; Zhongli, Liu [China Academy of Engineering Physics, Chengdu (China)

2001-04-01

A CT technique for laser-plasma diagnostic and a three-dimensional (3D) image reconstruction program (CT3D) have been developed. The 3D images of the laser-plasma are reconstructed by using a multiplication algebraic reconstruction technique (MART) from five pinhole camera images obtained along different sight directions. The technique has been used to measure the three-dimensional distribution of X-ray of laser-plasma experiments in Xingguang II device, and the good results are obtained. This shows that a CT technique can be applied to ICF experiments.

Three-dimensional Reciprocal Structures: Morphology, Concepts, Generative Rules

DEFF Research Database (Denmark)

Parigi, Dario; Pugnale, Alberto

2012-01-01

, causing every configuration to develop naturally out-of the plane. The structures presented here were developed and built by the students of the Master of Science in “Architectural Design” during a two week long workshop organized at Aalborg University in the fall semester 2011.......This paper present seven different three dimensional structures based on the principle of structural reciprocity with superimposition joint and standardized un-notched elements. Such typology could be regarded as being intrinsically three-dimensional because elements sit one of the top of the other...

Flukacad/Pipsicad: three-dimensional interfaces between Fluka and Autocad

International Nuclear Information System (INIS)

Helmut Vincke

2001-01-01

FLUKA is a widely used 3-D particle transport program. Up to now there was no possibility to display the simulation geometry or the calculated tracks in three dimensions. Even with FLUKA there exists only an option to picture two-dimensional views through the geometry used. This paper covers the description of two interface programs between the particle transport code FLUKA and the CAD program AutoCAD. These programs provide a three-dimensional facility not only for illustrating the simulated FLUKA geometry (FLUKACAD), but also for picturing simulated particle tracks (PIPSICAD) in a three-dimensional set-up. Additionally, the programming strategy for connecting FLUKA with AutoCAD is shown. A number of useful features of the programs themselves, but also of AutoCAD in the context of FLUKACAD and PIPSICAD, are explained. (authors)

Usefulness of three dimensional reconstructive images for thoracic trauma induced fractures

Energy Technology Data Exchange (ETDEWEB)

Koh, Kyung Hun; Kim, Dong Hun; Kim, Young Sook; Byun, Joo Nam [Chosun University Hospital, Gwangju (Korea, Republic of)

2006-09-15

We wanted to evaluate the usefulness of three-dimensional reconstructive images using multidetector computed tomography (MDCT) for thoracic traumatic patients visiting emergency room. 76 patients with fractures of the 105 patients who visited our emergency room with complaints of thoracic trauma were analyzed retrospectively. All the patients had thoracic MDCT performed and the three-dimensional reconstructive images were taken. The fractures were confirmed by axial CT, the clinical information, whole body bone scanning and the multiplanar reformation images. Plain x-ray images were analyzed by the fractured sites in a blind comparison of two radiologists' readings, and then that finding was compared with the axial CT scans and the three-dimensional reconstructive images. The fracture sites were rib (n 68), sternum (n = 14), clavicle (n = 6), scapula (n = 3), spine (n = 5) and combined fractures (n = 14). Plain x-ray and axial CT scans had a correspondency of 0.555 for the rib fractures. Axial CT scans and the three-dimensional reconstructive images had a correspondency of .952. For sternal fractures, those values were 0.692 and 0.928, respectively. The axial CT scans and three-dimensional reconstructive images showed sensitivities of 94% and 91% for rib and other fractures, respectively, and 93% and 100% for sternal fracture, respectively. Three-dimensional reconstructive image had an especially high sensitivity for the diagnosis of sternal fracture. While evaluating thoracic trauma at the emergency room, the three-dimensional reconstructive image was useful to easily diagnose the extent of fracture and it was very sensitive for detecting sternal fracture.

Usefulness of three dimensional reconstructive images for thoracic trauma induced fractures

International Nuclear Information System (INIS)

Koh, Kyung Hun; Kim, Dong Hun; Kim, Young Sook; Byun, Joo Nam

2006-01-01

We wanted to evaluate the usefulness of three-dimensional reconstructive images using multidetector computed tomography (MDCT) for thoracic traumatic patients visiting emergency room. 76 patients with fractures of the 105 patients who visited our emergency room with complaints of thoracic trauma were analyzed retrospectively. All the patients had thoracic MDCT performed and the three-dimensional reconstructive images were taken. The fractures were confirmed by axial CT, the clinical information, whole body bone scanning and the multiplanar reformation images. Plain x-ray images were analyzed by the fractured sites in a blind comparison of two radiologists' readings, and then that finding was compared with the axial CT scans and the three-dimensional reconstructive images. The fracture sites were rib (n 68), sternum (n = 14), clavicle (n = 6), scapula (n = 3), spine (n = 5) and combined fractures (n = 14). Plain x-ray and axial CT scans had a correspondency of 0.555 for the rib fractures. Axial CT scans and the three-dimensional reconstructive images had a correspondency of .952. For sternal fractures, those values were 0.692 and 0.928, respectively. The axial CT scans and three-dimensional reconstructive images showed sensitivities of 94% and 91% for rib and other fractures, respectively, and 93% and 100% for sternal fracture, respectively. Three-dimensional reconstructive image had an especially high sensitivity for the diagnosis of sternal fracture. While evaluating thoracic trauma at the emergency room, the three-dimensional reconstructive image was useful to easily diagnose the extent of fracture and it was very sensitive for detecting sternal fracture

Three-dimensional accuracy of plastic transfer impression copings for three implant systems.

Science.gov (United States)

Teo, Juin Wei; Tan, Keson B; Nicholls, Jack I; Wong, Keng Mun; Uy, Joanne

2014-01-01

The purpose of this study was to compare the three-dimensional accuracy of indirect plastic impression copings and direct implant-level impression copings from three implant systems (Nobel Biocare [NB], Biomet 3i [3i], and Straumann [STR]) at three interimplant buccolingual angulations (0, 8, and 15 degrees). Two-implant master models were used to simulate a three-unit implant fixed partial denture. Test models were made from Impregum impressions using direct implant-level impression copings (DR). Abutments were then connected to the master models for impressions using the plastic impression copings (INDR) at three different angulations for a total of 18 test groups (n = 5 in each group). A coordinate measuring machine was used to measure linear distortions, three-dimensional (3D) distortions, angular distortions, and absolute angular distortions between the master and test models. Three-way analysis of variance showed that the implant system had a significant effect on 3D distortions and absolute angular distortions in the x- and y-axes. Interimplant angulation had a significant effect on 3D distortions and absolute angular distortions in the y-axis. Impression technique had a significant effect on absolute angular distortions in the y-axis. With DR, the NB and 3i systems were not significantly different. With INDR, 3i appeared to have less distortion than the other systems. Interimplant angulations did not significantly affect the accuracy of NBDR, 3iINDR, and STRINDR. The accuracy of INDR and DR was comparable at all interimplant angulations for 3i and STR. For NB, INDR was comparable to DR at 0 and 8 degrees but was less accurate at 15 degrees. Three-dimensional accuracy of implant impressions varied with implant system, interimplant angulation, and impression technique.

Phase Diagrams of Three-Dimensional Anderson and Quantum Percolation Models Using Deep Three-Dimensional Convolutional Neural Network

Science.gov (United States)

Mano, Tomohiro; Ohtsuki, Tomi

2017-11-01

The three-dimensional Anderson model is a well-studied model of disordered electron systems that shows the delocalization-localization transition. As in our previous papers on two- and three-dimensional (2D, 3D) quantum phase transitions [J. Phys. Soc. Jpn. 85, 123706 (2016), 86, 044708 (2017)], we used an image recognition algorithm based on a multilayered convolutional neural network. However, in contrast to previous papers in which 2D image recognition was used, we applied 3D image recognition to analyze entire 3D wave functions. We show that a full phase diagram of the disorder-energy plane is obtained once the 3D convolutional neural network has been trained at the band center. We further demonstrate that the full phase diagram for 3D quantum bond and site percolations can be drawn by training the 3D Anderson model at the band center.

Three dimensional force prediction in a model linear brushless dc motor

Energy Technology Data Exchange (ETDEWEB)

Moghani, J.S.; Eastham, J.F.; Akmese, R.; Hill-Cottingham, R.J. (Univ. of Bath (United Kingdom). School of Electronic and Electric Engineering)

1994-11-01

Practical results are presented for the three axes forces produced on the primary of a linear brushless dc machine which is supplied from a three-phase delta-modulated inverter. Conditions of both lateral alignment and lateral displacement are considered. Finite element analysis using both two and three dimensional modeling is compared with the practical results. It is shown that a modified two dimensional model is adequate, where it can be used, in the aligned position and that the full three dimensional method gives good results when the machine is axially misaligned.

Transient analysis of cutoff waveguide antenna in three-dimensional space

International Nuclear Information System (INIS)

Kashiwa, Tatsuya; Yoshida, Norinobu; Fukai, Ichiro

1986-01-01

Recently, the exciting system for electric power heating as seen in nuclear fusion plasma heating and medical purpose has been actively studied and developed. Since such system treats basically a neighborhood field, various problems unlike conventional exciting system for communication arise. In such situation, the structure having the waveguides of simple and robust construction as the main body has been proposed. In this exciting system including the condition of media, the complex distribution of a neighborhood field based on a three-dimensional structure exerts an important effect on the characteristics. Especially in large power excitation, the higher mode of relatively small power distribution cannot be neglected. Besides, also a transient field distribution exerts an important effect on the characteristics, and the time response analysis is required. In this analysis, by the three-dimensional time response analysis method using Bergeron method, the unified analysis of the total system comprising a cutoff waveguide, a coaxial exciting part and a heating region was carried out for determining a radiation neighborhood electromagnetic field by a cutoff waveguide antenna. (Kako, I.)

The confusion effect when attacking simulated three-dimensional starling flocks.

Science.gov (United States)

Hogan, Benedict G; Hildenbrandt, Hanno; Scott-Samuel, Nicholas E; Cuthill, Innes C; Hemelrijk, Charlotte K

2017-01-01

The confusion effect describes the phenomenon of decreasing predator attack success with increasing prey group size. However, there is a paucity of research into the influence of this effect in coherent groups, such as flocks of European starlings ( Sturnus vulgaris ). Here, for the first time, we use a computer game style experiment to investigate the confusion effect in three dimensions. To date, computerized studies on the confusion effect have used two-dimensional simulations with simplistic prey movement and dynamics. Our experiment is the first investigation of the effects of flock size and density on the ability of a (human) predator to track and capture a target starling in a realistically simulated three-dimensional flock of starlings. In line with the predictions of the confusion effect, modelled starlings appear to be safer from predation in larger and denser flocks. This finding lends credence to previous suggestions that starling flocks have anti-predator benefits and, more generally, it suggests that active increases in density in animal groups in response to predation may increase the effectiveness of the confusion effect.

Visual Interpretation with Three-Dimensional Annotations (VITA): three-dimensional image interpretation tool for radiological reporting.

Science.gov (United States)

Roy, Sharmili; Brown, Michael S; Shih, George L

2014-02-01

This paper introduces a software framework called Visual Interpretation with Three-Dimensional Annotations (VITA) that is able to automatically generate three-dimensional (3D) visual summaries based on radiological annotations made during routine exam reporting. VITA summaries are in the form of rotating 3D volumes where radiological annotations are highlighted to place important clinical observations into a 3D context. The rendered volume is produced as a Digital Imaging and Communications in Medicine (DICOM) object and is automatically added to the study for archival in Picture Archiving and Communication System (PACS). In addition, a video summary (e.g., MPEG4) can be generated for sharing with patients and for situations where DICOM viewers are not readily available to referring physicians. The current version of VITA is compatible with ClearCanvas; however, VITA can work with any PACS workstation that has a structured annotation implementation (e.g., Extendible Markup Language, Health Level 7, Annotation and Image Markup) and is able to seamlessly integrate into the existing reporting workflow. In a survey with referring physicians, the vast majority strongly agreed that 3D visual summaries improve the communication of the radiologists' reports and aid communication with patients.

Three-dimensional Simulation of Backward Raman Amplification

International Nuclear Information System (INIS)

Balakin, A.A.; Fraiman, G.M.; Fisch, N.J.

2005-01-01

Three-dimensional (3-D) simulations for the Backward Raman Amplification (BRA) are presented. The images illustrate the effects of pump depletion, pulse diffraction, non-homogeneous plasma density, and plasma ionization

Three dimensional transport model for toroidal plasmas

International Nuclear Information System (INIS)

Copenhauer, C.

1980-12-01

A nonlinear MHD model, developed for three-dimensional toroidal geometries (asymmetric) and for high β (β approximately epsilon), is used as a basis for a three-dimensional transport model. Since inertia terms are needed in describing evolving magnetic islands, the model can calculate transport, both in the transient phase before nonlinear saturation of magnetic islands and afterwards on the resistive time scale. In the β approximately epsilon ordering, the plasma does not have sufficient energy to compress the parallel magnetic field, which allows the Alfven wave to be eliminated in the reduced nonlinear equations, and the model then follows the slower time scales. The resulting perpendicular and parallel plasma drift velocities can be identified with those of guiding center theory

Three dimensional imaging in cardiac nuclear medicine

International Nuclear Information System (INIS)

Torizuka, Kanji; Ishii, Yasushi; Yonekura, Yoshiharu; Yamamoto, Kazutaka; Tamaki, Takeyoshi

1981-01-01

Methods to obtain three dimensional images of the heart were reviewed. Gated three dimensional display reconstructed from images using bidirectional collimator, was a useful method to detect akinesis of the heart wall. Tomographic observation of the heart can be carried out by a pinhole collimator to image ischemia with high sensitivity. However the focusing plane must be carefully selected to prevent false positives. In the case of emission CT (ECT), utilization of positron emitters gave a quantitative image without correction, whereas single photon ECT needed the correction due to the absorption of γ-ray. Though the reliability of the images by ECT was high, the time required for data acquisition was much longer than that by a 7 pinhole or bidirectional collimator. (Nakanishi, T.)

[Three-dimensional computer aided design for individualized post-and-core restoration].

Science.gov (United States)

Gu, Xiao-yu; Wang, Ya-ping; Wang, Yong; Lü, Pei-jun

2009-10-01

To develop a method of three-dimensional computer aided design (CAD) of post-and-core restoration. Two plaster casts with extracted natural teeth were used in this study. The extracted teeth were prepared and scanned using tomography method to obtain three-dimensional digitalized models. According to the basic rules of post-and-core design, posts, cores and cavity surfaces of the teeth were designed using the tools for processing point clouds, curves and surfaces on the forward engineering software of Tanglong prosthodontic system. Then three-dimensional figures of the final restorations were corrected according to the configurations of anterior teeth, premolars and molars respectively. Computer aided design of 14 post-and-core restorations were finished, and good fitness between the restoration and the three-dimensional digital models were obtained. Appropriate retention forms and enough spaces for the full crown restorations can be obtained through this method. The CAD of three-dimensional figures of the post-and-core restorations can fulfill clinical requirements. Therefore they can be used in computer-aided manufacture (CAM) of post-and-core restorations.

Three-dimensional propagation in near-field tomographic X-ray phase retrieval

International Nuclear Information System (INIS)

Ruhlandt, Aike; Salditt, Tim

2016-01-01

An extension of phase retrieval algorithms for near-field X-ray (propagation) imaging to three dimensions is presented, enhancing the quality of the reconstruction by exploiting previously unused three-dimensional consistency constraints. This paper presents an extension of phase retrieval algorithms for near-field X-ray (propagation) imaging to three dimensions, enhancing the quality of the reconstruction by exploiting previously unused three-dimensional consistency constraints. The approach is based on a novel three-dimensional propagator and is derived for the case of optically weak objects. It can be easily implemented in current phase retrieval architectures, is computationally efficient and reduces the need for restrictive prior assumptions, resulting in superior reconstruction quality

Three dimensional reconstruction of tomographic images of the retina

International Nuclear Information System (INIS)

Glittenberg, C.; Zeiler, F.; Falkner, C.; Binder, S.; Povazay, B.; Hermann, B.; Drexler, W.

2007-01-01

The development of a new display system for the three-dimensional visualization of tomographic images in ophthalmology. Specifically, a system that can use stacks of B-mode scans from an ultrahigh resolution optical tomography examination to vividly display retinal specimens as three-dimensional objects. Several subroutines were programmed in the rendering and raytracing program Cinema 4D XL 9.102 Studio Bundle (Maxon Computer Inc., Friedrichsburg, Germany), which could process stacks of tomographic scans into three-dimensional objects. Ultrahigh resolution optical coherence tomography examinations were performed on patients with various retinal pathologies and post processed with the subroutines that had been designed. All ultrahigh resolution optical coherence tomographies were performed with a titanium: sapphire based ultra broad bandwidth (160 nm) femtosecond laser system (INTEGRAL, Femtolasers Productions GmbH. Vienna Austria) with an axial resolution of 3 μm. A new three dimensional display system for tomographic images in ophthalmology was developed, which allows a highly vivid display of physiological and pathological structures of the retina. The system also distinguishes itself through its high interactivity and adaptability. This new display system allows the visualization of physiological and pathological structures of the retina in a new way, which will give us new insight into their morphology and development. (author) [de

The Structure and Dynamics of An Active Galactic Nucleus Torus : CO Line Predictions for ALMA from Three-dimensional Hydrodynamical Simulations with X-ray-driven Chemistry

NARCIS (Netherlands)

Perez Beaupuits, J.P.; Wada, K.; Spaans, M.

2011-01-01

Several attempts have been made to model the mass distribution and dynamical evolution of the circumnuclear gas in active galactic nuclei (AGNs). However, chemical evolution is not included in detail in three-dimensional (3D) hydrodynamic simulations. The X-ray radiation from the AGN can drive the

Clinical significance of three-dimensional sonohysterography

International Nuclear Information System (INIS)

Lee, Eun Hye; Lee, Mi Hwa; Lee, Chan; Kim, Jong Wook; Shin, Myung Choel

1999-01-01

To evaluate the usefulness of three dimensional sonohysterography (3D SHG) in the evaluation of uterine endometrial and submucosal lesions in comparison with conventional two-dimensional sonohysterography (2D SHG). Our series consisted of 26 patients (mean aged 41 years) who complained of uterine bleeding, menorrhagia, or dysmenorrhea. 2D SHG was performed, and then 3D SHG was done after the volume mode was switched on. Simultaneous display of three perpendicular two-dimensional planes and surface rendering of findings on particular section were obtained. We analyzed whether the endometrium was thickened or not, and the location, size, shape, echogenicity, posterior shadowing, and echogenic rim of the focal lesion. The results were compared with the pathologic findings or MRI. There were submucosal myomas (n=12), intramural myomas (n=2), endometrial polyps (n=7), placental polyp (n=1), and normal endometrial cavities (n=4) on SHG. Nineteen cases were confirmed by pathologic findings or MRI. The results were correlated in 89% (17/19) of the cases. We misdiagnosed 2 cases: focal endometrial hyperplasia and choriocarcinoma were misdiagnosed as endometrial polyp and placental polyp, respectively. Imaging diagnoses were same in the techniques. Comparing with 2D SHG, 3D SHG provided a subjective display of pathologic findings and an additional information about spatial relationship between focal lesion and surroundings.

Clinical significance of three-dimensional sonohysterography

Energy Technology Data Exchange (ETDEWEB)

Lee, Eun Hye; Lee, Mi Hwa; Lee, Chan; Kim, Jong Wook; Shin, Myung Choel [Pochon Cha University College of Medicine, Pochon (Korea, Republic of)

1999-12-15

To evaluate the usefulness of three dimensional sonohysterography (3D SHG) in the evaluation of uterine endometrial and submucosal lesions in comparison with conventional two-dimensional sonohysterography (2D SHG). Our series consisted of 26 patients (mean aged 41 years) who complained of uterine bleeding, menorrhagia, or dysmenorrhea. 2D SHG was performed, and then 3D SHG was done after the volume mode was switched on. Simultaneous display of three perpendicular two-dimensional planes and surface rendering of findings on particular section were obtained. We analyzed whether the endometrium was thickened or not, and the location, size, shape, echogenicity, posterior shadowing, and echogenic rim of the focal lesion. The results were compared with the pathologic findings or MRI. There were submucosal myomas (n=12), intramural myomas (n=2), endometrial polyps (n=7), placental polyp (n=1), and normal endometrial cavities (n=4) on SHG. Nineteen cases were confirmed by pathologic findings or MRI. The results were correlated in 89% (17/19) of the cases. We misdiagnosed 2 cases: focal endometrial hyperplasia and choriocarcinoma were misdiagnosed as endometrial polyp and placental polyp, respectively. Imaging diagnoses were same in the techniques. Comparing with 2D SHG, 3D SHG provided a subjective display of pathologic findings and an additional information about spatial relationship between focal lesion and surroundings.

Prognostic value of three-dimensional ultrasound for fetal hydronephrosis

Science.gov (United States)

WANG, JUNMEI; YING, WEIWEN; TANG, DAXING; YANG, LIMING; LIU, DONGSHENG; LIU, YUANHUI; PAN, JIAOE; XIE, XING

2015-01-01

The present study evaluated the prognostic value of three-dimensional ultrasound for fetal hydronephrosis. Pregnant females with fetal hydronephrosis were enrolled and a novel three-dimensional ultrasound indicator, renal parenchymal volume/kidney volume, was introduced to predict the postnatal prognosis of fetal hydronephrosis in comparison with commonly used ultrasound indicators. All ultrasound indicators of fetal hydronephrosis could predict whether postnatal surgery was required for fetal hydronephrosis; however, the predictive performance of renal parenchymal volume/kidney volume measurements as an individual indicator was the highest. In conclusion, ultrasound is important in predicting whether postnatal surgery is required for fetal hydronephrosis, and the three-dimensional ultrasound indicator renal parenchymal volume/kidney volume has a high predictive performance. Furthermore, the majority of cases of fetal hydronephrosis spontaneously regress subsequent to birth, and the regression time is closely associated with ultrasound indicators. PMID:25667626

Imaging unsteady three-dimensional transport phenomena

Indian Academy of Sciences (India)

2014-01-05

Jan 5, 2014 ... The image data can be jointly analysed with the physical laws governing transport and principles of image formation. Hence, with the experiment suitably carried out, three-dimensional physical domains with unsteady processes can be accommodated. Optical methods promise to breach the holy grail of ...

Usefulness Of Three-Dimensional Printing Models for Patients with Stoma Construction

OpenAIRE

Tominaga, Tetsuro; Takagi, Katsunori; Takeshita, Hiroaki; Miyamoto, Tomo; Shimoda, Kozue; Matsuo, Ayano; Matsumoto, Keitaro; Hidaka, Shigekazu; Yamasaki, Naoya; Sawai, Terumitsu; Nagayasu, Takeshi

2016-01-01

The use of patient-specific organ models in three-dimensional printing systems could be helpful for the education of patients and medical students. The aim of this study was to clarify whether the use of patient-specific stoma models is helpful for patient education. From January 2014 to September 2014, 5 patients who underwent colorectal surgery and for whom a temporary or permanent stoma had been created were involved in this study. Three-dimensional stoma models and three-dimensional face ...

Loop expansion in massless three-dimensional QED

International Nuclear Information System (INIS)

Guendelman, E.I.; Radulovic, Z.M.

1983-01-01

It is shown how the loop expansion in massless three-dimensional QED can be made finite, up to three loops, by absorbing the infrared divergences in a gauge-fixing term. The same method removes leading and first subleading singularities to all orders of perturbation theory, and all singularities of the fermion self-energy to four loops

[Application Progress of Three-dimensional Laser Scanning Technology in Medical Surface Mapping].

Science.gov (United States)

Zhang, Yonghong; Hou, He; Han, Yuchuan; Wang, Ning; Zhang, Ying; Zhu, Xianfeng; Wang, Mingshi

2016-04-01

The booming three-dimensional laser scanning technology can efficiently and effectively get spatial three-dimensional coordinates of the detected object surface and reconstruct the image at high speed,high precision and large capacity of information.Non-radiation,non-contact and the ability of visualization make it increasingly popular in three-dimensional surface medical mapping.This paper reviews the applications and developments of three-dimensional laser scanning technology in medical field,especially in stomatology,plastic surgery and orthopedics.Furthermore,the paper also discusses the application prospects in the future as well as the biomedical engineering problems it would encounter with.

Comparison of two three-dimensional cephalometric analysis computer software

OpenAIRE

Sawchuk, Dena; Alhadlaq, Adel; Alkhadra, Thamer; Carlyle, Terry D; Kusnoto, Budi; El-Bialy, Tarek

2014-01-01

Background: Three-dimensional cephalometric analyses are getting more attraction in orthodontics. The aim of this study was to compare two softwares to evaluate three-dimensional cephalometric analyses of orthodontic treatment outcomes. Materials and Methods: Twenty cone beam computed tomography images were obtained using i-CAT® imaging system from patient's records as part of their regular orthodontic records. The images were analyzed using InVivoDental5.0 (Anatomage Inc.) and 3DCeph™ (Unive...

Three-dimensional transesophageal echocardiography of the atrial septal defects

Directory of Open Access Journals (Sweden)

Romero-Cárdenas Ángel

2008-07-01

Full Text Available Abstract Transesophageal echocardiography has advantages over transthoracic technique in defining morphology of atrial structures. Even though real time three-dimensional echocardiographic imaging is a reality, the off-line reconstruction technique usually allows to obtain higher spatial resolution images. The purpose of this study was to explore the accuracy of off-line three-dimensional transesophageal echocardiography in a spectrum of atrial septal defects by comparing them with representative anatomic specimens.

Symmetries, integrals, and three-dimensional reductions of Plebanski's second heavenly equation

International Nuclear Information System (INIS)

Neyzi, F.; Sheftel, M. B.; Yazici, D.

2007-01-01

We study symmetries and conservation laws for Plebanski's second heavenly equation written as a first-order nonlinear evolutionary system which admits a multi-Hamiltonian structure. We construct an optimal system of one-dimensional subalgebras and all inequivalent three-dimensional symmetry reductions of the original four-dimensional system. We consider these two-component evolutionary systems in three dimensions as natural candidates for integrable systems

Upper bound on the capacity of constrained three-dimensional codes

DEFF Research Database (Denmark)

Forchhammer, Søren

2000-01-01

An upper bound on the capacity of constrained three-dimensional codes is presented. The bound for two-dimensional codes of Calkin and Wilf (see SIAM Journal of Discrete Mathematics, vol.11, no.1, p.54-60, 1998) was extended to three dimensions by Nagy and Zeger. Both bounds apply to first order s...

Teaching veterinary obstetrics using three-dimensional animation technology.

Science.gov (United States)

Scherzer, Jakob; Buchanan, M Flint; Moore, James N; White, Susan L

2010-01-01

In this three-year study, test scores for students taught veterinary obstetrics in a classroom setting with either traditional media (photographs, text, and two-dimensional graphical presentations) were compared with those for students taught by incorporating three-dimensional (3D) media (linear animations and interactive QuickTime Virtual Reality models) into the classroom lectures. Incorporation of the 3D animations and interactive models significantly increased students' scores on essay questions designed to assess their comprehension of the subject matter. This approach to education may help to better prepare students for dealing with obstetrical cases during their final clinical year and after graduation.

Three-dimensional wax patterning of paper fluidic devices.

Science.gov (United States)

Renault, Christophe; Koehne, Jessica; Ricco, Antonio J; Crooks, Richard M

2014-06-17

In this paper we describe a method for three-dimensional wax patterning of microfluidic paper-based analytical devices (μPADs). The method is rooted in the fundamental details of wax transport in paper and provides a simple way to fabricate complex channel architectures such as hemichannels and fully enclosed channels. We show that three-dimensional μPADs can be fabricated with half as much paper by using hemichannels rather than ordinary open channels. We also provide evidence that fully enclosed channels are efficiently isolated from the exterior environment, decreasing contamination risks, simplifying the handling of the device, and slowing evaporation of solvents.

Estimation of three-dimensional radar tracking using modified extended kalman filter

Science.gov (United States)

Aditya, Prima; Apriliani, Erna; Khusnul Arif, Didik; Baihaqi, Komar

2018-03-01

Kalman filter is an estimation method by combining data and mathematical models then developed be extended Kalman filter to handle nonlinear systems. Three-dimensional radar tracking is one of example of nonlinear system. In this paper developed a modification method of extended Kalman filter from the direct decline of the three-dimensional radar tracking case. The development of this filter algorithm can solve the three-dimensional radar measurements in the case proposed in this case the target measured by radar with distance r, azimuth angle θ, and the elevation angle ϕ. Artificial covariance and mean adjusted directly on the three-dimensional radar system. Simulations result show that the proposed formulation is effective in the calculation of nonlinear measurement compared with extended Kalman filter with the value error at 0.77% until 1.15%.

Three-dimensional structure of porcine pancreatic carboxypeptidase B with an acetate ion and two zinc atoms in the active site

Energy Technology Data Exchange (ETDEWEB)

Akparov, V. Kh., E-mail: valery@akparov.ru [State Research Institute for Genetics and Selection of Industrial Microorganisms (Russian Federation); Timofeev, V. I., E-mail: tostars@mail.ru [Russian Academy of Sciences, Shubnikov Institute of Crystallography of Federal Scientific Research Centre “Crystallography and Photonics” (Russian Federation); Maghsoudi, N. N., E-mail: maghsudi@yahoo.com [Shahid Beheshti University of Medical Sciences, Neuroscience Research Center (Iran, Islamic Republic of); Kuranova, I. P. [Russian Academy of Sciences, Shubnikov Institute of Crystallography of Federal Scientific Research Centre “Crystallography and Photonics” (Russian Federation)

2017-03-15

Crystals of porcine pancreatic carboxypeptidase B (CPB) were grown by the capillary counter-diffusion method in the presence of polyethylene glycol and zinc acetate. The three-dimensional structure of CPB was determined at 1.40 Å resolution using the X-ray diffraction data set collected from the crystals of the enzyme at the SPring 8 synchrotron facility and was refined to R{sub fact} = 17.19%, R{sub free} = 19.78%. The structure contains five zinc atoms, two of which are present in the active site of the enzyme, and an acetate ion. The arrangement of an additional zinc atom in the active site and the acetate ion is different from that reported by Yoshimoto et al.

Pattern formation in three-dimensional reaction-diffusion systems

Science.gov (United States)

Callahan, T. K.; Knobloch, E.

1999-08-01

Existing group theoretic analysis of pattern formation in three dimensions [T.K. Callahan, E. Knobloch, Symmetry-breaking bifurcations on cubic lattices, Nonlinearity 10 (1997) 1179-1216] is used to make specific predictions about the formation of three-dimensional patterns in two models of the Turing instability, the Brusselator model and the Lengyel-Epstein model. Spatially periodic patterns having the periodicity of the simple cubic (SC), face-centered cubic (FCC) or body-centered cubic (BCC) lattices are considered. An efficient center manifold reduction is described and used to identify parameter regimes permitting stable lamellæ, SC, FCC, double-diamond, hexagonal prism, BCC and BCCI states. Both models possess a special wavenumber k* at which the normal form coefficients take on fixed model-independent ratios and both are described by identical bifurcation diagrams. This property is generic for two-species chemical reaction-diffusion models with a single activator and inhibitor.

Three-dimensional model of a selective theophylline-binding RNA molecule

Energy Technology Data Exchange (ETDEWEB)

Tung, Chang-Shung; Oprea, T.I.; Hummer, G.; Garcia, A.E.

1995-07-01

We propose a three-dimensional (3D) model for an RNA molecule that selectively binds theophylline but not caffeine. This RNA, which was found using SELEX [Jenison, R.D., et al., Science (1994) 263:1425] is 10,000 times more specific for theophylline (Kd=320 nM) than for caffeine (Kd=3.5 mM), although the two ligands are identical except for a methyl group substituted at N7 (present only in caffeine). The binding affinity for ten xanthine-based ligands was used to derive a Comparative Molecular Field Analysis (CoMFA) model (R{sup 2} = 0.93 for 3 components, with cross-validated R{sup 2} of 0.73), using the SYBYL and GOLPE programs. A pharmacophoric map was generated to locate steric and electrostatic interactions between theophylline and the RNA binding site. This information was used to identify putative functional groups of the binding pocket and to generate distance constraints. Based on a model for the secondary structure (Jenison et al., idem), the 3D structure of this RNA was then generated using the following method: each helical region of the RNA molecule was treated as a rigid body; single-stranded loops with specific end-to-end distances were generated. The structures of RNA-xanthine complexes were studied using a modified Monte Carlo algorithm. The detailed structure of an RNA-ligand complex model, as well as possible explanations for the theophylline selectivity will be discussed.

Three-Dimensional Structure Determination of Botulinum Toxin

National Research Council Canada - National Science Library

Stevens, Ray

1997-01-01

...) Based on the structure of the neurotoxin, understand the toxins mechanism of action. We have accomplished the first goal of determining the three-dimensional structure of the 150 kD botulinum neurotoxin serotype...

Three-Dimensional Structure Determination of Botulinum Toxin

National Research Council Canada - National Science Library

Stevens, Ray

1998-01-01

...) Based on the structure of the neurotoxin, understand the toxins mechanism of action. We have accomplished the first goal of determining the three-dimensional structure of the 150 kD botulinum neurotoxin serotype...

Self-assembled three dimensional network designs for soft electronics.

Science.gov (United States)

Jang, Kyung-In; Li, Kan; Chung, Ha Uk; Xu, Sheng; Jung, Han Na; Yang, Yiyuan; Kwak, Jean Won; Jung, Han Hee; Song, Juwon; Yang, Ce; Wang, Ao; Liu, Zhuangjian; Lee, Jong Yoon; Kim, Bong Hoon; Kim, Jae-Hwan; Lee, Jungyup; Yu, Yongjoon; Kim, Bum Jun; Jang, Hokyung; Yu, Ki Jun; Kim, Jeonghyun; Lee, Jung Woo; Jeong, Jae-Woong; Song, Young Min; Huang, Yonggang; Zhang, Yihui; Rogers, John A

2017-06-21

Low modulus, compliant systems of sensors, circuits and radios designed to intimately interface with the soft tissues of the human body are of growing interest, due to their emerging applications in continuous, clinical-quality health monitors and advanced, bioelectronic therapeutics. Although recent research establishes various materials and mechanics concepts for such technologies, all existing approaches involve simple, two-dimensional (2D) layouts in the constituent micro-components and interconnects. Here we introduce concepts in three-dimensional (3D) architectures that bypass important engineering constraints and performance limitations set by traditional, 2D designs. Specifically, open-mesh, 3D interconnect networks of helical microcoils formed by deterministic compressive buckling establish the basis for systems that can offer exceptional low modulus, elastic mechanics, in compact geometries, with active components and sophisticated levels of functionality. Coupled mechanical and electrical design approaches enable layout optimization, assembly processes and encapsulation schemes to yield 3D configurations that satisfy requirements in demanding, complex systems, such as wireless, skin-compatible electronic sensors.

Self-assembled three dimensional network designs for soft electronics

Science.gov (United States)

Jang, Kyung-In; Li, Kan; Chung, Ha Uk; Xu, Sheng; Jung, Han Na; Yang, Yiyuan; Kwak, Jean Won; Jung, Han Hee; Song, Juwon; Yang, Ce; Wang, Ao; Liu, Zhuangjian; Lee, Jong Yoon; Kim, Bong Hoon; Kim, Jae-Hwan; Lee, Jungyup; Yu, Yongjoon; Kim, Bum Jun; Jang, Hokyung; Yu, Ki Jun; Kim, Jeonghyun; Lee, Jung Woo; Jeong, Jae-Woong; Song, Young Min; Huang, Yonggang; Zhang, Yihui; Rogers, John A.

2017-06-01

Low modulus, compliant systems of sensors, circuits and radios designed to intimately interface with the soft tissues of the human body are of growing interest, due to their emerging applications in continuous, clinical-quality health monitors and advanced, bioelectronic therapeutics. Although recent research establishes various materials and mechanics concepts for such technologies, all existing approaches involve simple, two-dimensional (2D) layouts in the constituent micro-components and interconnects. Here we introduce concepts in three-dimensional (3D) architectures that bypass important engineering constraints and performance limitations set by traditional, 2D designs. Specifically, open-mesh, 3D interconnect networks of helical microcoils formed by deterministic compressive buckling establish the basis for systems that can offer exceptional low modulus, elastic mechanics, in compact geometries, with active components and sophisticated levels of functionality. Coupled mechanical and electrical design approaches enable layout optimization, assembly processes and encapsulation schemes to yield 3D configurations that satisfy requirements in demanding, complex systems, such as wireless, skin-compatible electronic sensors.

Three-dimensional MRI of the glenoid labrum

International Nuclear Information System (INIS)

Loehr, S.P.; Pope, T.L. Jr.; Martin, D.F.; Link, K.M.; Monu, J.U.V.; Hunter, M.; Reboussin, D.

1995-01-01

The objective of this study was to assess the accuracy of three-dimensional (3D) magnetic resonance imaging (MRI) reformation in the evaluation of tears of the glenoid labrum complex (GLC). Fifty-five shoulders were evaluated by MRI using standard spin-echo sequences. Gradient-refocused-echo axial projections were used to assess the GLC on the two-dimensional (2D) studies. Three-dimensional Fourier transform multiplanar gradient-recalled imaging with a resolution of 0.7 mm was also performed in all patients. Independent analyses of the anterior and posterior labra were performed in a blinded manner for both the 2D and 3D studies by three experienced musculoskeletal radiologists. Observations of the imaging studies were compared with the videoarthroscopic findings. The appearance of the GLC was rated on a scale of 0 to 4 (0-2=normal, 3, 4=abnormal or torn). The diagnostic confidence was averaged from the three reader's scores. Anterior labral tears were effectively detected with sensitivities of 89% and 96% and specificities of 96% and 100% (P<0.0001) for the 2D and 3D studies, respectively. For posterior labral tears, the sensitivity and specificity of the 2D method were 47% and 98%, respectively. The sensitivity and specificity of the 3D volume sequence were 53% and 98%, respectively. The lower sensitivity of both imaging methods for detecting posterior labral tears may be influenced by the smaller number (n=5) of arthroscopically confirmed cases in our study and reflects the difficulty of visualizing the posteroinferior borders of the GLC with present MRI techniques. (orig.)

Infrared magneto-spectroscopy of two-dimensional and three-dimensional massless fermions: A comparison

Energy Technology Data Exchange (ETDEWEB)

Orlita, M., E-mail: milan.orlita@lncmi.cnrs.fr [Laboratoire National des Champs Magnétiques Intenses, CNRS-UJF-UPS-INSA, 38042 Grenoble (France); Faculty of Mathematics and Physics, Charles University, Ke Karlovu 5, 121 16 Prague 2 (Czech Republic); Faugeras, C.; Barra, A.-L.; Martinez, G.; Potemski, M. [Laboratoire National des Champs Magnétiques Intenses, CNRS-UJF-UPS-INSA, 38042 Grenoble (France); Basko, D. M. [LPMMC UMR 5493, Université Grenoble 1/CNRS, B.P. 166, 38042 Grenoble (France); Zholudev, M. S. [Laboratoire Charles Coulomb (L2C), UMR CNRS 5221, GIS-TERALAB, Université Montpellier II, 34095 Montpellier (France); Institute for Physics of Microstructures, RAS, Nizhny Novgorod GSP-105 603950 (Russian Federation); Teppe, F.; Knap, W. [Laboratoire Charles Coulomb (L2C), UMR CNRS 5221, GIS-TERALAB, Université Montpellier II, 34095 Montpellier (France); Gavrilenko, V. I. [Institute for Physics of Microstructures, RAS, Nizhny Novgorod GSP-105 603950 (Russian Federation); Mikhailov, N. N.; Dvoretskii, S. A. [A.V. Rzhanov Institute of Semiconductor Physics, Siberian Branch, Russian Academy of Sciences, Novosibirsk 630090 (Russian Federation); Neugebauer, P. [Institut für Physikalische Chemie, Universität Stuttgart, Pfaffenwaldring 55, 70569 Stuttgart (Germany); Berger, C. [School of Physics, Georgia Institute of Technology, Atlanta, Georgia 30332 (United States); Institut Néel/CNRS-UJF BP 166, F-38042 Grenoble Cedex 9 (France); Heer, W. A. de [School of Physics, Georgia Institute of Technology, Atlanta, Georgia 30332 (United States)

2015-03-21

Here, we report on a magneto-optical study of two distinct systems hosting massless fermions—two-dimensional graphene and three-dimensional HgCdTe tuned to the zero band gap condition at the point of the semiconductor-to-semimetal topological transition. Both materials exhibit, in the quantum regime, a fairly rich magneto-optical response, which is composed from a series of intra- and interband inter-Landau level resonances with for massless fermions typical √(B) dependence. The impact of the system's dimensionality and of the strength of the spin-orbit interaction on the optical response is also discussed.

Three dimensional system integration

CERN Document Server

Papanikolaou, Antonis; Radojcic, Riko

2010-01-01

Three-dimensional (3D) integrated circuit (IC) stacking is the next big step in electronic system integration. It enables packing more functionality, as well as integration of heterogeneous materials, devices, and signals, in the same space (volume). This results in consumer electronics (e.g., mobile, handheld devices) which can run more powerful applications, such as full-length movies and 3D games, with longer battery life. This technology is so promising that it is expected to be a mainstream technology a few years from now, less than 10-15 years from its original conception. To achieve thi

Turbulence in Three Dimensional Simulations of Magnetopause Reconnection

Science.gov (United States)

Drake, J. F.; Price, L.; Swisdak, M.; Burch, J. L.; Cassak, P.; Dahlin, J. T.; Ergun, R.

2017-12-01

We present two- and three-dimensional particle-in-cell simulations of the 16 October 2015 MMS magnetopause reconnection event. While the two-dimensional simulation is laminar, turbulence develops at both the x-line and along the magnetic separatrices in the three-dimensional simulation. This turbulence is electromagnetic in nature, is characterized by a wavevector k given by kρ e ˜(m_e/m_i)0.25 with ρ e the electron Larmor radius, and appears to have the ion pressure gradient as its source of free energy. Taken together, these results suggest the instability is a variant of the lower-hybrid drift instability. The turbulence produces electric field fluctuations in the out-of-plane direction (the direction of the reconnection electric field) with an amplitude of around ± 10 mV/m, which is much greater than the reconnection electric field of around 0.1 mV/m. Such large values of the out-of-plane electric field have been identified in the MMS data. The turbulence in the simulation controls the scale lengths of the density profile and current layers in asymmetric reconnection, driving them closer to √ {ρ eρ_i } than the ρ e or de scalings seen in 2D reconnection simulations, where de is the electron inertial length. The turbulence is strong enough to make the magnetic field around the reconnection island chaotic and produces both anomalous resistivity and anomalous viscosity. Each contribute significantly to breaking the frozen-in condition in the electron diffusion region. The crescent-shaped features in velocity space seen both in MMS observations and in two-dimensional simulations survive, even in the turbulent environment of the three-dimensional system. We compare and contrast these results to a three-dimensional simulation of the 8 December 2015 MMS magnetopause reconnection event in which the reconnecting and out-of-plane guide fields are comparable. LHDI is still present in this event, although its appearance is modified by the presence of the guide

Free-fall dynamics of a pair of rigidly linked disks

Science.gov (United States)

Kim, Taehyun; Chang, Jaehyeock; Kim, Daegyoum

2018-03-01

We investigate experimentally the free-fall motion of a pair of identical disks rigidly connected to each other. The three-dimensional coordinates of the pair of falling disks were constructed to quantitatively describe its trajectory, and the flow structure formed by the disk pair was identified by using dye visualization. The rigidly linked disk pair exhibits a novel falling pattern that creates a helical path with a conical configuration in which the lower disk rotates in a wider radius than the upper disk with respect to a vertical axis. The helical motion occurs consistently for the range of disk separation examined in this study. The dye visualization reveals that a strong, noticeable helical vortex core is generated from the outer tip of the lower disk during the helical motion. With an increasing length ratio, which is the ratio of the disk separation to the diameter of the disks, the nutation angle and the rate of change in the precession angle that characterize the combined helical and conical kinematics decrease linearly, whereas the pitch of the helical path increases linearly. Although all disk pairs undergo this helical motion, the horizontal-drift patterns of the disk pair depend on the length ratio.

Two- and three-dimensional CT evaluation of sacral and pelvic anomalies

International Nuclear Information System (INIS)

Kuhlman, J.E.; Fishman, E.K.; Magid, D.

1988-01-01

Pelvic anomalies are difficult to evaluate with standard techniques. Detailed knowledge of the existing pelvic structures and musculature is essential for successful repair. The authors evaluated 12 patients with complex malformations of the pelvis using two- and three-dimensional imaging. The anomalies included bladder exstrophy (n = 4), cloacal exstrophy (n = 1), duplicated and absent sacrum (n = 3), myelomeningoceles (n = 2), and diastrophic dwarfism (n = 2). The two-dimensional images consisted of sequential coronal and sagittal reconstructions that could be reviewed dynamically on screen. Three-dimensional images were generated on the Pixar imaging computer with use of volumetric rendering. Two- and three-dimensional CT proved complementary in the evaluation of pelvic anomalies, providing optimal information from transaxial CT data

Three-dimensional stellarator equilibrium as an ohmic steady state

International Nuclear Information System (INIS)

Park, W.; Monticello, D.A.; Strauss, H.; Manickam, J.

1985-07-01

A stable three-dimensional stellarator equilibrium can be obtained numerically by a time-dependent relaxation method using small values of dissipation. The final state is an ohmic steady state which approaches an ohmic equilibrium in the limit of small dissipation coefficients. We describe a method to speed up the relaxation process and a method to implement the B vector . del p = 0 condition. These methods are applied to obtain three-dimensional heliac equilibria using the reduced heliac equations

A retrospective and prospective survey of three-dimensional transport calculations

International Nuclear Information System (INIS)

Nakahara, Yasuaki

1985-01-01

A retrospective survey is made on the three-dimensional radiation transport calculations. Introduction is given to computer codes based on the distinctive numerical methods such as the Monte Carlo, Direct Integration, Ssub(n) and Finite Element Methods to solve the three-dimensional transport equations. Prospective discussions are made on pros and cons of these methods. (author)

Early orthognathic surgery with three-dimensional image simulation during presurgical orthodontics in adults.

Science.gov (United States)

Kang, Sang-Hoon; Kim, Moon-Key; Park, Sun-Yeon; Lee, Ji-Yeon; Park, Wonse; Lee, Sang-Hwy

2011-03-01

To correct dentofacial deformities, three-dimensional skeletal analysis and computerized orthognathic surgery simulation are used to facilitate accurate diagnoses and surgical plans. Computed tomography imaging of dental occlusion can inform three-dimensional facial analyses and orthognathic surgical simulations. Furthermore, three-dimensional laser scans of a cast model of the predetermined postoperative dental occlusion can be used to increase the accuracy of the preoperative surgical simulation. In this study, we prepared cast models of planned postoperative dental occlusions from 12 patients diagnosed with skeletal class III malocclusions with mandibular prognathism and facial asymmetry that had planned to undergo bimaxillary orthognathic surgery during preoperative orthodontic treatment. The data from three-dimensional laser scans of the cast models were used in three-dimensional surgical simulations. Early orthognathic surgeries were performed based on three-dimensional image simulations using the cast images in several presurgical orthodontic states in which teeth alignment, leveling, and space closure were incomplete. After postoperative orthodontic treatments, intraoral examinations revealed that no patient had a posterior open bite or space. The two-dimensional and three-dimensional skeletal analyses showed that no mandibular deviations occurred between the immediate and final postoperative states of orthodontic treatment. These results showed that early orthognathic surgery with three-dimensional computerized simulations based on cast models of predetermined postoperative dental occlusions could provide early correction of facial deformities and improved efficacy of preoperative orthodontic treatment. This approach can reduce the decompensation treatment period of the presurgical orthodontics and contribute to efficient postoperative orthodontic treatments.

Damageable contact between an elastic body and a rigid foundation

Science.gov (United States)

Campo, M.; Fernández, J. R.; Silva, A.

2009-02-01

In this work, the contact problem between an elastic body and a rigid obstacle is studied, including the development of material damage which results from internal compression or tension. The variational problem is formulated as a first-kind variational inequality for the displacements coupled with a parabolic partial differential equation for the damage field. The existence of a unique local weak solution is stated. Then, a fully discrete scheme is introduced using the finite element method to approximate the spatial variable and an Euler scheme to discretize the time derivatives. Error estimates are derived on the approximate solutions, from which the linear convergence of the algorithm is deduced under suitable regularity conditions. Finally, three two-dimensional numerical simulations are performed to demonstrate the accuracy and the behaviour of the scheme.

Reliability of tunnel angle in ACL reconstruction: two-dimensional versus three-dimensional guide technique.

Science.gov (United States)

Leiter, Jeff R S; de Korompay, Nevin; Macdonald, Lindsey; McRae, Sheila; Froese, Warren; Macdonald, Peter B

2011-08-01

To compare the reliability of tibial tunnel position and angle produced with a standard ACL guide (two-dimensional guide) or Howell 65° Guide (three-dimensional guide) in the coronal and sagittal planes. In the sagittal plane, the dependent variables were the angle of the tibial tunnel relative to the tibial plateau and the position of the tibial tunnel with respect to the most posterior aspect of the tibia. In the coronal plane, the dependent variables were the angle of the tunnel with respect to the medial joint line of the tibia and the medial and lateral placement of the tibial tunnel relative to the most medial aspect of the tibia. The position and angle of the tibial tunnel in the coronal and sagittal planes were determined from anteroposterior and lateral radiographs, respectively, taken 2-6 months postoperatively. The two-dimensional and three-dimensional guide groups included 28 and 24 sets of radiographs, respectively. Tibial tunnel position was identified, and tunnel angle measurements were completed. Multiple investigators measured the position and angle of the tunnel 3 times, at least 7 days apart. The angle of the tibial tunnel in the coronal plane using a two-dimensional guide (61.3 ± 4.8°) was more horizontal (P guide (64.7 ± 6.2°). The position of the tibial tunnel in the sagittal plane was more anterior (P guide group compared to the three-dimensional guide group (43.3 ± 2.9%). The Howell Tibial Guide allows for reliable placement of the tibial tunnel in the coronal plane at an angle of 65°. Tibial tunnels were within the anatomical footprint of the ACL with either technique. Future studies should investigate the effects of tibial tunnel angle on knee function and patient quality of life. Case-control retrospective comparative study, Level III.

Three-dimensional characterization of stress corrosion cracks

DEFF Research Database (Denmark)

Lozano-Perez, S.; Rodrigo, P.; Gontard, Lionel Cervera

2011-01-01

the best spatial resolution. To illustrate the power of these techniques, different parts of dominant stress corrosion cracks in Ni-alloys and stainless steels have been reconstructed in 3D. All relevant microstructural features can now be studied in detail and its relative orientation respect......Understanding crack propagation and initiation is fundamental if stress corrosion cracking (SCC) mechanisms are to be understood. However, cracking is a three-dimensional (3D) phenomenon and most characterization techniques are restricted to two-dimensional (2D) observations. In order to overcome...

Controlled synthesis of three-dimensional hierarchical Bi2WO6 microspheres with optimum photocatalytic activity

International Nuclear Information System (INIS)

Wang, Hong; Song, Jimei; Zhang, Hui; Gao, Fei; Zhao, Shaojuan; Hu, Haiqin

2012-01-01

Highlights: ► The synthesized method is very simple. It can be widely used in the production. ► The morphology is novel and the property is fine. ► The formation of 3D hierarchical microsphere can be induced by changing the concentration of KNO 3 . -- Abstract: Three-dimensional (3D) hierarchical Bi 2 WO 6 microsphere and octahedral Bi 2 WO 6 have been synthesized by a facile hydrothermal method using KNO 3 solution and distilled water as solvent, respectively. The obtained products were characterized by X-ray diffraction, scanning electron microscopy, N 2 adsorption/desorption, and UV–vis diffuse reflectance spectroscopy in detail. The concentration of KNO 3 played a key role in the formation of 3D hierarchical Bi 2 WO 6 microspheres. A possible formation mechanism of Bi 2 WO 6 microsphere was proposed. The photocatalytic activity of the as-synthesized products was evaluated by monitoring the degradation of MB solution under sunlight irradiation. It was found that the photocatalytic activity of the 3D hierarchical Bi 2 WO 6 microsphere was superior to the octahedral Bi 2 WO 6 , which was attributed to the larger surface area and special hierarchical structure of Bi 2 WO 6 microsphere.

Two- and three-dimensional evaluation of the acetabulum in the pediatric patient

International Nuclear Information System (INIS)

Magid, D.; Fishman, E.K.; Sponseller, P.D.

1987-01-01

Complex anatomic structures such as the hip and acetabulum are best evaluated with the use of two- and three-dimensional reconstruction techniques and standard transaxial CT data. CT scans of children with various hip pathologies, including congenital hip dislocation, slipped capital femoral epiphyses, hip dysplasias, dwarfism, and acetabular fractures, were reviewed to determine the value of two- and three-dimensional imaging. The advantages of two-dimensional imaging techniques (sequential coronal/sagittal reconstruction) and three-dimensional valumetric imaging techniques (using real-time video display) are illustrated with specific examples

Dynamic three-dimensional display of common congenital cardiac defects from reconstruction of two-dimensional echocardiographic images.

Science.gov (United States)

Hsieh, K S; Lin, C C; Liu, W S; Chen, F L

1996-01-01

Two-dimensional echocardiography had long been a standard diagnostic modality for congenital heart disease. Further attempts of three-dimensional reconstruction using two-dimensional echocardiographic images to visualize stereotypic structure of cardiac lesions have been successful only recently. So far only very few studies have been done to display three-dimensional anatomy of the heart through two-dimensional image acquisition because such complex procedures were involved. This study introduced a recently developed image acquisition and processing system for dynamic three-dimensional visualization of various congenital cardiac lesions. From December 1994 to April 1995, 35 cases were selected in the Echo Laboratory here from about 3000 Echo examinations completed. Each image was acquired on-line with specially designed high resolution image grazmber with EKG and respiratory gating technique. Off-line image processing using a window-architectured interactive software package includes construction of 2-D ehcocardiographic pixel to 3-D "voxel" with conversion of orthogonal to rotatory axial system, interpolation, extraction of region of interest, segmentation, shading and, finally, 3D rendering. Three-dimensional anatomy of various congenital cardiac defects was shown, including four cases with ventricular septal defects, two cases with atrial septal defects, and two cases with aortic stenosis. Dynamic reconstruction of a "beating heart" is recorded as vedio tape with video interface. The potential application of 3D display of the reconstruction from 2D echocardiographic images for the diagnosis of various congenital heart defects has been shown. The 3D display was able to improve the diagnostic ability of echocardiography, and clear-cut display of the various congenital cardiac defects and vavular stenosis could be demonstrated. Reinforcement of current techniques will expand future application of 3D display of conventional 2D images.

Extinction maps toward the Milky Way bulge: Two-dimensional and three-dimensional tests with apogee

Energy Technology Data Exchange (ETDEWEB)

Schultheis, M. [Université de Nice Sophia-Antipolis, CNRS, Observatoire de Côte d' Azur, Laboratoire Lagrange, 06304 Nice Cedex 4 (France); Zasowski, G. [Department of Physics and Astronomy, Johns Hopkins University, Baltimore, MD 21218 (United States); Allende Prieto, C. [Instituto de Astrofísica de Canarias, Calle Vía Láctea s/n, E-38205 La Laguna, Tenerife (Spain); Anders, F.; Chiappini, C. [Leibniz-Institut für Astrophysik Potsdam (AIP), D-14482 Potsdam (Germany); Beaton, R. L.; García Pérez, A. E.; Majewski, S. R. [Department of Astronomy, University of Virginia, Charlottesville, VA 22904 (United States); Beers, T. C. [National Optical Astronomy Observatory, Tucson, AZ 85719 (United States); Bizyaev, D. [Apache Point Observatory, Sunspot, NM 88349 (United States); Frinchaboy, P. M. [Department of Physics and Astronomy, Texas Christian University, TCU Box 298840, Fort Worth, TX 76129 (United States); Ge, J. [Astronomy Department, University of Florida, Gainesville, FL 32611 (United States); Hearty, F.; Schneider, D. P. [Department of Astronomy and Astrophysics, The Pennsylvania State University, University Park, PA 16802 (United States); Holtzman, J. [New Mexico State University, Las Cruces, NM 88003 (United States); Muna, D. [Department of Astronomy, The Ohio State University, Columbus, OH 43210 (United States); Nidever, D. [Department of Astronomy, University of Michigan, Ann Arbor, MI 48109 (United States); Shetrone, M., E-mail: mathias.schultheis@oca.eu, E-mail: gail.zasowski@gmail.com [McDonald Observatory, The University of Texas at Austin, Austin, TX 78712 (United States)

2014-07-01

Galactic interstellar extinction maps are powerful and necessary tools for Milky Way structure and stellar population analyses, particularly toward the heavily reddened bulge and in the midplane. However, due to the difficulty of obtaining reliable extinction measures and distances for a large number of stars that are independent of these maps, tests of their accuracy and systematics have been limited. Our goal is to assess a variety of photometric stellar extinction estimates, including both two-dimensional and three-dimensional extinction maps, using independent extinction measures based on a large spectroscopic sample of stars toward the Milky Way bulge. We employ stellar atmospheric parameters derived from high-resolution H-band Apache Point Observatory Galactic Evolution Experiment (APOGEE) spectra, combined with theoretical stellar isochrones, to calculate line-of-sight extinction and distances for a sample of more than 2400 giants toward the Milky Way bulge. We compare these extinction values to those predicted by individual near-IR and near+mid-IR stellar colors, two-dimensional bulge extinction maps, and three-dimensional extinction maps. The long baseline, near+mid-IR stellar colors are, on average, the most accurate predictors of the APOGEE extinction estimates, and the two-dimensional and three-dimensional extinction maps derived from different stellar populations along different sightlines show varying degrees of reliability. We present the results of all of the comparisons and discuss reasons for the observed discrepancies. We also demonstrate how the particular stellar atmospheric models adopted can have a strong impact on this type of analysis, and discuss related caveats.

Extinction maps toward the Milky Way bulge: Two-dimensional and three-dimensional tests with apogee

International Nuclear Information System (INIS)

Schultheis, M.; Zasowski, G.; Allende Prieto, C.; Anders, F.; Chiappini, C.; Beaton, R. L.; García Pérez, A. E.; Majewski, S. R.; Beers, T. C.; Bizyaev, D.; Frinchaboy, P. M.; Ge, J.; Hearty, F.; Schneider, D. P.; Holtzman, J.; Muna, D.; Nidever, D.; Shetrone, M.

2014-01-01

Galactic interstellar extinction maps are powerful and necessary tools for Milky Way structure and stellar population analyses, particularly toward the heavily reddened bulge and in the midplane. However, due to the difficulty of obtaining reliable extinction measures and distances for a large number of stars that are independent of these maps, tests of their accuracy and systematics have been limited. Our goal is to assess a variety of photometric stellar extinction estimates, including both two-dimensional and three-dimensional extinction maps, using independent extinction measures based on a large spectroscopic sample of stars toward the Milky Way bulge. We employ stellar atmospheric parameters derived from high-resolution H-band Apache Point Observatory Galactic Evolution Experiment (APOGEE) spectra, combined with theoretical stellar isochrones, to calculate line-of-sight extinction and distances for a sample of more than 2400 giants toward the Milky Way bulge. We compare these extinction values to those predicted by individual near-IR and near+mid-IR stellar colors, two-dimensional bulge extinction maps, and three-dimensional extinction maps. The long baseline, near+mid-IR stellar colors are, on average, the most accurate predictors of the APOGEE extinction estimates, and the two-dimensional and three-dimensional extinction maps derived from different stellar populations along different sightlines show varying degrees of reliability. We present the results of all of the comparisons and discuss reasons for the observed discrepancies. We also demonstrate how the particular stellar atmospheric models adopted can have a strong impact on this type of analysis, and discuss related caveats.

Superconductivity and the existence of Nambu's three-dimensional phase space mechanics

International Nuclear Information System (INIS)

Angulo, R.; Gonzalez-Bernardo, C.A.; Rodriguez-Gomez, J.; Kalnay, A.J.; Perez-M, F.; Tello-Llanos, R.A.

1984-01-01

Nambu proposed a generalization of hamiltonian mechanics such that three-dimensional phase space is allowed. Thanks to a recent paper by Holm and Kupershmidt we are able to show the existence of such three-dimensional phase space systems in superconductivity. (orig.)

Three-dimensional stereo by photometric ratios

International Nuclear Information System (INIS)

Wolff, L.B.; Angelopoulou, E.

1994-01-01

We present a methodology for corresponding a dense set of points on an object surface from photometric values for three-dimensional stereo computation of depth. The methodology utilizes multiple stereo pairs of images, with each stereo pair being taken of the identical scene but under different illumination. With just two stereo pairs of images taken under two different illumination conditions, a stereo pair of ratio images can be produced, one for the ratio of left-hand images and one for the ratio of right-hand images. We demonstrate how the photometric ratios composing these images can be used for accurate correspondence of object points. Object points having the same photometric ratio with respect to two different illumination conditions constitute a well-defined equivalence class of physical constraints defined by local surface orientation relative to illumination conditions. We formally show that for diffuse reflection the photometric ratio is invariant to varying camera characteristics, surface albedo, and viewpoint and that therefore the same photometric ratio in both images of a stereo pair implies the same equivalence class of physical constraints. The correspondence of photometric ratios along epipolar lines in a stereo pair of images under different illumination conditions is a correspondence of equivalent physical constraints, and the determination of depth from stereo can be performed. Whereas illumination planning is required, our photometric-based stereo methodology does not require knowledge of illumination conditions in the actual computation of three-dimensional depth and is applicable to perspective views. This technique extends the stereo determination of three-dimensional depth to smooth featureless surfaces without the use of precisely calibrated lighting. We demonstrate experimental depth maps from a dense set of points on smooth objects of known ground-truth shape, determined to within 1% depth accuracy

Three-dimensional metallic opals fabricated by double templating

International Nuclear Information System (INIS)

Yan Qingfeng; Nukala, Pavan; Chiang, Yet-Ming; Wong, C.C.

2009-01-01

We report a simple and cost-effective double templating method for fabricating large-area three-dimensional metallic photonic crystals of controlled thickness. A self-assembled polystyrene opal was used as the first template to fabricate a silica inverse opal on a gold-coated glass substrate via sol-gel processing. Gold was subsequently infiltrated to the pores of the silica inverse opal using electrochemical deposition. A high-quality three-dimensional gold photonic crystal was obtained after removal of the secondary template (silica inverse opal). The effects of template sphere size and deposition current density on the gold growth rate, and the resulting morphology and growth mechanism of the gold opal, were investigated.

Three-dimensional quadrupole lenses made with permanent magnets

International Nuclear Information System (INIS)

Ivanov, A.S.

1984-01-01

The performance of accelerator systems with quadrupole magnets can be improved by using permanent magnets in quadrupole lenses. This requires better methods for treating the three-dimensional nature of the magnetic fields and the nonlinear characteristics of the magnets. A numerical method is described for simulating three-dimensional magnetic fields and used to analyze quadrupole lenses and doublets with permanent magnets. The results, which are confirmed experimentally, indicate that both the quadrupole magnetic gradient and the effective field length are changed in permanent-magnet quadrupole lenses when the pole lengths and the gap between the lenses are varied while the other characteristics of the magnets remain unchanged

Rigid body dynamics of mechanisms

CERN Document Server

Hahn, Hubert

2003-01-01

The second volume of Rigid Body Dynamics of Mechanisms covers applications via a systematic method for deriving model equations of planar and spatial mechanisms. The necessary theoretical foundations have been laid in the first volume that introduces the theoretical mechanical aspects of mechatronic systems. Here the focus is on the application of the modeling methodology to various examples of rigid-body mechanisms, simple planar ones as well as more challenging spatial problems. A rich variety of joint models, active constraints, plus active and passive force elements is treated. The book is intended for self-study by working engineers and students concerned with the control of mechanical systems, i.e. robotics, mechatronics, vehicles, and machine tools. The examples included are a likely source from which to choose models for university lectures.

CFT description of three-dimensional Kerr-de Sitter spacetime

International Nuclear Information System (INIS)

Fjelstad, Jens; Hwang, Stephen; Maansson, Teresia

2002-01-01

We describe three-dimensional Kerr-de Sitter space using similar methods as recently applied to the BTZ black hole. A rigorous form of the classical connection between gravity in three dimensions and two-dimensional conformal field theory is employed, where the fundamental degrees of freedom are described in terms of two dependent SL(2,C) currents. In contrast to the BTZ case, however, quantization does not give the Bekenstein-Hawking entropy connected to the cosmological horizon of Kerr-de Sitter space

CFT description of three-dimensional Kerr-de Sitter spacetime

Energy Technology Data Exchange (ETDEWEB)

Fjelstad, Jens E-mail: jens.fjelstad@kau.se; Hwang, Stephen E-mail: stephen.hwang@kau.se; Maansson, Teresia E-mail: teresia@physto.se

2002-10-07

We describe three-dimensional Kerr-de Sitter space using similar methods as recently applied to the BTZ black hole. A rigorous form of the classical connection between gravity in three dimensions and two-dimensional conformal field theory is employed, where the fundamental degrees of freedom are described in terms of two dependent SL(2,C) currents. In contrast to the BTZ case, however, quantization does not give the Bekenstein-Hawking entropy connected to the cosmological horizon of Kerr-de Sitter space.

Radiological evaluation of the fetal face using three-dimensional ultrasound imaging

Directory of Open Access Journals (Sweden)

Bäumler M

2012-12-01

Full Text Available Marcel Bäumler,1–3 Michèle Bigorre,1,4 Jean-Michel Faure1,51CHU Montpellier, Centre de Compétence des Fentes Faciales, Hôpital Lapeyronie, Montpellier, 2Clinique du Parc, Imagerie de la Femme, Castelnau-le-Lez, 3Cabinet de Radiologie du Trident, Lunel, 4CHU Service de Chirurgie Plastique Pédiatrique, Hôpital Lapeyronie, Montpellier, 5CHU Montpellier, Service de Gynécologie-Obstétrique, Hôpital Arnaud de Villeneuve, Montpellier, FranceAbstract: This paper reviews screening and three-dimensional diagnostic ultrasound imaging of the fetal face. The different techniques available for analyzing biometric and morphological items of the profile, eyes, ears, lips, and hard and soft palate are commented on and briefly compared with the respective bi-dimensional techniques. The available literature supports the use of three-dimensional ultrasound in difficult prenatal diagnostic conditions because of its diagnostic accuracy, enabling improved safety of perinatal care. Globally, a marked increase has been observed in the accuracy of three-dimensional ultrasound in comparison with the bi-dimensional approach. Because there is no consensus about the performance of the different three-dimensional techniques, future studies are needed in order to compare them and to find the best technique for analysis of each of the respective facial elements. Universal prenatal standards may integrate these potential new findings in the future. At this time, the existing guidelines for prenatal facial screening should not be changed.Keywords: prenatal three-dimensional ultrasound, prenatal screening, prenatal diagnosis, cleft lip and palate, fetal profile, retrognathism

Research and Realization of Medical Image Fusion Based on Three-Dimensional Reconstruction

Institute of Scientific and Technical Information of China (English)

无

2007-01-01

A new medical image fusion technique is presented. The method is based on three-dimensional reconstruction. After reconstruction, the three-dimensional volume data is normalized by three-dimensional coordinate conversion in the same way and intercepted through setting up cutting plane including anatomical structure, as a result two images in entire registration on space and geometry are obtained and the images are fused at last.Compared with traditional two-dimensional fusion technique, three-dimensional fusion technique can not only resolve the different problems existed in the two kinds of images, but also avoid the registration error of the two kinds of images when they have different scan and imaging parameter. The research proves this fusion technique is more exact and has no registration, so it is more adapt to arbitrary medical image fusion with different equipments.

Three-dimensional Modeling of Type Ia Supernova Explosions

Science.gov (United States)

Khokhlov, Alexei

2001-06-01

A deflagration explosion of a Type Ia Supernova (SNIa) is studied using three-dimensional, high-resolution, adaptive mesh refinement fluid dynamic calculations. Deflagration speed in an exploding Chandrasekhar-mass carbon-oxygen white dwarf (WD) grows exponentially, reaches approximately 30the speed of sound, and then declines due to a WD expansion. Outermost layers of the WD remain unburned. The explosion energy is comparable to that of a Type Ia supernova. The freezing of turbulent motions by expansion appears to be a crucial physical mechanism regulating the strength of a supernova explosion. In contrast to one-dimensional models, three-dimensional calculations predict the formation of Si-group elements and pockets of unburned CO in the middle and in central regions of a supernova ejecta. This, and the presence of unburned outer layer of carbon-oxygen may pose problems for SNIa spectra. Explosion sensitivity to initial conditions and its relation to a diversity of SNIa is discussed.

Creating three-dimensional thermal maps

CSIR Research Space (South Africa)

Price

2011-11-01

Full Text Available stream_source_info Price_2011.pdf.txt stream_content_type text/plain stream_size 30895 Content-Encoding ISO-8859-1 stream_name Price_2011.pdf.txt Content-Type text/plain; charset=ISO-8859-1 Creating Three...-Dimensional Thermal Maps Mathew Price Cogency cc Cape Town Email: mathew@cogency.co.za Jeremy Green CSIR Centre for Mining Innovation Johannesburg Email: jgreen@csir.co.za John Dickens CSIR Centre for Mining Innovation Johannesburg Email: jdickens...

three dimensional photoelastic investigations on thick rectangular

African Journals Online (AJOL)

user

1983-09-01

Sep 1, 1983 ... Thick rectangular plates are investigated by means of three-dimensional photoelasticity ... a thin plate theory and a higher order thick plate theory. 1. ..... number of fringes lest the accuracy of the results will be considerably.

Surgical accuracy of three-dimensional virtual planning

DEFF Research Database (Denmark)

Stokbro, Kasper; Aagaard, Esben; Torkov, Peter

2016-01-01

This retrospective study evaluated the precision and positional accuracy of different orthognathic procedures following virtual surgical planning in 30 patients. To date, no studies of three-dimensional virtual surgical planning have evaluated the influence of segmentation on positional accuracy...... and transverse expansion. Furthermore, only a few have evaluated the precision and accuracy of genioplasty in placement of the chin segment. The virtual surgical plan was compared with the postsurgical outcome by using three linear and three rotational measurements. The influence of maxillary segmentation...

Three-dimensional motion analysis of an improved head immobilization system for simulation, CT, MRI, and PET imaging

International Nuclear Information System (INIS)

Thornton, A.F. Jr.; Ten Haken, R.K.; Gerhardsson, A.; Correll, M.

1991-01-01

A mask/marker immobilization system for the routine radiation therapy treatment of head and neck disease is described, utilizing a commercially available thermoplastic mesh, indexed and mounted for a rigid frame attached to the therapy couch. Designed to permit CT, MRI, and PET diagnostics scans of the patient to be performed in the simulation and treatment position employing the same mask, the system has been tested in order to demonstrate the reproducibility of immobilization throughout a radical course of irradiation. Three-dimensional analysis of patient position over an 8-week course of daily radiation treatment has been performed for 9 patients from digitization of anatomic points identified on orthogonal radiographs. Studies employing weekly constructed system permits rapid mask formation to be performed on the treatment simulator, resulting in an immobilization device comparable to masks produced with vacuum-forming techniques. Details of motion analysis and central axis CT, MRI, and PET markers are offered. (author). 16 refs.; 3 figs

Understanding geological processes: Visualization of rigid and non-rigid transformations

Science.gov (United States)

Shipley, T. F.; Atit, K.; Manduca, C. A.; Ormand, C. J.; Resnick, I.; Tikoff, B.

2012-12-01

Visualizations are used in the geological sciences to support reasoning about structures and events. Research in cognitive sciences offers insights into the range of skills of different users, and ultimately how visualizations might support different users. To understand the range of skills needed to reason about earth processes we have developed a program of research that is grounded in the geosciences' careful description of the spatial and spatiotemporal patterns associated with earth processes. In particular, we are pursuing a research program that identifies specific spatial skills and investigates whether and how they are related to each other. For this study, we focus on a specific question: Is there an important distinction in the geosciences between rigid and non-rigid deformation? To study a general spatial thinking skill we employed displays with non-geological objects that had been altered by rigid change (rotation), and two types of non-rigid change ("brittle" (or discontinuous) and "ductile" (or continuous) deformation). Disciplinary scientists (geosciences and chemistry faculty), and novices (non-science faculty and undergraduate psychology students) answered questions that required them to visualize the appearance of the object before the change. In one study, geologists and chemists were found to be superior to non-science faculty in reasoning about rigid rotations (e.g., what an object would look like from a different perspective). Geologists were superior to chemists in reasoning about brittle deformations (e.g., what an object looked like before it was broken - here the object was a word cut into many fragments displaced in different directions). This finding is consistent with two hypotheses: 1) Experts are good at visualizing the types of changes required for their domain; and 2) Visualization of rigid and non-rigid changes are not the same skill. An additional important finding is that there was a broad range of skill in both rigid and non-rigid

Method and system for manipulating a digital representation of a three-dimensional object

DEFF Research Database (Denmark)

2010-01-01

A method of manipulating a three-dimensional virtual building block model by means of two-dimensional cursor movements, the virtual building block model including a plurality of virtual building blocks each including a number of connection elements for connecting the virtual building block...... with another virtual building block according to a set of connection rules, the method comprising positioning by means of cursor movements in a computer display area representing a two-dimensional projection of said model, a two-dimensional projection of a first virtual building block to be connected...... to the structure, resulting in a two-dimensional position; determining, from the two-dimensional position, a number of three-dimensional candidate positions of the first virtual building block in the three-dimensional coordinate system; selecting one of said candidate positions based on the connection rules...

Multi-particle three-dimensional coordinate estimation in real-time optical manipulation

DEFF Research Database (Denmark)

Dam, Jeppe Seidelin; Perch-Nielsen, Ivan R.; Palima, Darwin

2009-01-01

We have previously shown how stereoscopic images can be obtained in our three-dimensional optical micromanipulation system [J. S. Dam et al, Opt. Express 16, 7244 (2008)]. Here, we present an extension and application of this principle to automatically gather the three-dimensional coordinates for...

Participatory three dimensional mapping for the preparation of landslide disaster risk reduction program

Science.gov (United States)

Kusratmoko, Eko; Wibowo, Adi; Cholid, Sofyan; Pin, Tjiong Giok

2017-07-01

This paper presents the results of applications of participatory three dimensional mapping (P3DM) method for fqcilitating the people of Cibanteng' village to compile a landslide disaster risk reduction program. Physical factors, as high rainfall, topography, geology and land use, and coupled with the condition of demographic and social-economic factors, make up the Cibanteng region highly susceptible to landslides. During the years 2013-2014 has happened 2 times landslides which caused economic losses, as a result of damage to homes and farmland. Participatory mapping is one part of the activities of community-based disaster risk reduction (CBDRR)), because of the involvement of local communities is a prerequisite for sustainable disaster risk reduction. In this activity, participatory mapping method are done in two ways, namely participatory two-dimensional mapping (P2DM) with a focus on mapping of disaster areas and participatory three-dimensional mapping (P3DM) with a focus on the entire territory of the village. Based on the results P3DM, the ability of the communities in understanding the village environment spatially well-tested and honed, so as to facilitate the preparation of the CBDRR programs. Furthermore, the P3DM method can be applied to another disaster areas, due to it becomes a medium of effective dialogue between all levels of involved communities.

Electron crystallography of three dimensional protein crystals

NARCIS (Netherlands)

Georgieva, Dilyana

2008-01-01

This thesis describes an investigation of the potential of electron diffraction for studying three dimensional sub-micro-crystals of proteins and pharmaceuticals. A prerequisite for using electron diffraction for structural studies is the predictable availability of tiny crystals. A method for

On-line analysis of algae in water by discrete three-dimensional fluorescence spectroscopy.

Science.gov (United States)

Zhao, Nanjing; Zhang, Xiaoling; Yin, Gaofang; Yang, Ruifang; Hu, Li; Chen, Shuang; Liu, Jianguo; Liu, Wenqing

2018-03-19

In view of the problem of the on-line measurement of algae classification, a method of algae classification and concentration determination based on the discrete three-dimensional fluorescence spectra was studied in this work. The discrete three-dimensional fluorescence spectra of twelve common species of algae belonging to five categories were analyzed, the discrete three-dimensional standard spectra of five categories were built, and the recognition, classification and concentration prediction of algae categories were realized by the discrete three-dimensional fluorescence spectra coupled with non-negative weighted least squares linear regression analysis. The results show that similarities between discrete three-dimensional standard spectra of different categories were reduced and the accuracies of recognition, classification and concentration prediction of the algae categories were significantly improved. By comparing with that of the chlorophyll a fluorescence excitation spectra method, the recognition accuracy rate in pure samples by discrete three-dimensional fluorescence spectra is improved 1.38%, and the recovery rate and classification accuracy in pure diatom samples 34.1% and 46.8%, respectively; the recognition accuracy rate of mixed samples by discrete-three dimensional fluorescence spectra is enhanced by 26.1%, the recovery rate of mixed samples with Chlorophyta 37.8%, and the classification accuracy of mixed samples with diatoms 54.6%.

Three-dimensional magnetic probe measurements of EXTRAP T1 equilibria

International Nuclear Information System (INIS)

Hedin, E.R.

1988-12-01

Internal probes are described for use in measuring the three orthogonal components of the magnetic field in the Extrap T1 device. The data analysis process for numerical processing of the probe signals is also explained. Results include radial and vertical profiles of the field components, three-dimensional field plots, inverse field strength contours, two-dimensional magnetic flux plots and toroidal current profiles. (author)

Three-dimensional dose-response models of risk for radiation injury carcinogenesis

International Nuclear Information System (INIS)

Raabe, O.G.

1988-01-01

The use of computer graphics in conjunction with three-dimensional models of dose-response relationships for chronic exposure to ionizing radiation dramaticly clarifies the separate and interactive roles of competing risks. The three dimensions are average dose rate, exposure time, and risk. As an example, the functionally injurious and carcinogenic responses after systemic uptake of Ra-226 by beagles, mice and people with consequent alpha particle irradiation of the bone are represented by three-dimensional dose-rate/time/response surfaces that demonstrate the contributions with the passage of time of the competing deleterious responses. These relationships are further evaluated by mathematical stripping with three-dimensional illustrations that graphically show the resultant separate contribution of each effect. Radiation bone injury predominates at high dose rates and bone cancer at intermediate dose rates. Low dose rates result in spontaneous deaths from natural aging, yielding a type of practical threshold for bone cancer induction. Risk assessment is benefited by the insights that become apparent with these three-dimensional models. The improved conceptualization afforded by them contributes to planning and evaluating epidemiological analyses and experimental studies

Induction of carcinoembryonic antigen expression in a three-dimensional culture system

Science.gov (United States)

Jessup, J. M.; Brown, D.; Fitzgerald, W.; Ford, R. D.; Nachman, A.; Goodwin, T. J.; Spaulding, G.

1994-01-01

MIP-101 is a poorly differentiated human colon carcinoma cell line established from ascites that produces minimal amounts of carcinoembryonic antigen (CEA), a 180 kDa glycoprotein tumor marker, and nonspecific cross-reacting antigen (NCA), a related protein that has 50 and 90 kDa isoforms, in vitro in monolayer culture. MIP-101 produces CEA when implanted into the peritoneum of nude mice but not when implanted into subcutaneous tissue. We tested whether MIP-101 cells may be induced to express CEA when cultured on microcarrier beads in three-dimensional cultures, either in static cultures as non-adherent aggregates or under dynamic conditions in a NASA-designed low shear stress bioreactor. MIP- 101 cells proliferated well under all three conditions and increased CEA and NCA production 3 - 4 fold when grown in three-dimensional cultures compared to MIP-101 cells growing logarithmically in monolayers. These results suggest that three-dimensional growth in vitro simulates tumor function in vivo and that three-dimensional growth by itself may enhance production of molecules that are associated with the metastatic process.

Three-dimensional demonstration of liver and spleen by computer graphics technique

International Nuclear Information System (INIS)

Kashiwagi, Toru; Azuma, Masayoshi; Katayama, Kazuhiro; Yoshioka, Hiroaki; Ishizu, Hiromi; Mitsutani, Natsuki; Koizumi, Takao; Takayama, Ichiro

1987-01-01

Three-dimensional demonstration system of the liver and spleen has been developed using computer graphics technique. Three-dimensional models were constructed from CT images of the organ surface. The three-dimensional images were displayed as wire-frame and/or solid models on the color CRT. The anatomical surface of the liver and spleen was realistically viewed from any direction. In liver cirrhosis, atrophy of the right lobe, hypertrophy of the left lobe and splenomegaly were displayed vividly. The liver and hepatoma were displayed as wire-frame and solid models respectively on the same image. This combined display clarified the intrahepatic location of hepatoma together with configuration of liver and hepatoma. Furthermore, superimposed display of three dimensional models and celiac angiogram enabled us to understand the location and configuration of lesions more easily than the original CT data or angiogram alone. Therefore, it is expected that this system is clinically useful for noninvasive evaluation of patho-morphological changes of the liver and spleen. (author)

Numerical Investigation of Three-dimensional Instability of Standing Waves

Science.gov (United States)

Zhu, Qiang; Liu, Yuming; Yue, Dick K. P.

2002-11-01

We study the three-dimensional instability of finite-amplitude standing waves under the influence of gravity using the transition matrix method. For accurate calculation of the transition matrices, we apply an efficient high-order spectral element method for nonlinear wave dynamics in complex domain. We consider two types of standing waves: (a) plane standing waves; and (b) standing waves in a circular tank. For the former, in addition to the confirmation of the side-band-like instability, we find a new three-dimensional instability for arbitrary base standing waves. The dominant component of the unstable disturbance is an oblique standing wave, with an arbitrary angle relative to the base flow, whose frequency is approximately equal to that of the base standing wave. Based on direct simulations, we confirm such a three-dimensional instability and show the occurrence of the Fermi-Pasta-Ulam recurrence phenomenon during nonlinear evolution. For the latter, we find that beyond a threshold wave steepness, the standing wave with frequency Ω becomes unstable to a small three-dimensional disturbance, which contains two dominant standing-wave components with frequencies ω1 and ω_2, provided that 2Ω ω1 + ω_2. The threshold wave steepness is found to decrease/increase as the radial/azimuthal wavenumber of the base standing wave increases. We show that the instability of standing waves in rectangular and circular tanks is caused by third-order quartet resonances between base flow and disturbance.

Three-dimensional metamaterials fabricated using Proton Beam Writing

Energy Technology Data Exchange (ETDEWEB)

Bettiol, A.A., E-mail: a.bettiol@nus.edu.sg [Centre for Ion Beam Applications, Department of Physics, National University of Singapore, 2 Science Dr. 3, Singapore 117542 (Singapore); Turaga, S.P.; Yan, Y.; Vanga, S.K. [Centre for Ion Beam Applications, Department of Physics, National University of Singapore, 2 Science Dr. 3, Singapore 117542 (Singapore); Chiam, S.Y. [NUS High School for Maths and Science, 20 Clementi Avenue 1, Singapore 129957 (Singapore)

2013-07-01

Proton Beam Writing (PBW) is a direct write lithographic technique that has recently been applied to the fabrication of three dimensional metamaterials. In this work, we show that the unique capabilities of PBW, namely the ability to fabricate arrays of high resolution, high aspect ratio microstructures in polymer or replicated into metal, is well suited to metamaterials research. We have also developed a novel method for selectively electroless plating silver directly onto polymer structures that were fabricated using PBW. This method opens up new avenues for utilizing PBW for making metamaterials and other sub-wavelength metallic structures. Several potential applications of three dimensional metamaterials fabricated using PBW are discussed, including sensing and negative refractive index materials.

SNAP-3D: a three-dimensional neutron diffusion code

International Nuclear Information System (INIS)

McCallien, C.W.J.

1975-10-01

A preliminary report is presented describing the data requirements of a one- two- or three-dimensional multi-group diffusion code, SNAP-3D. This code is primarily intended for neutron diffusion calculations but it can also carry out gamma calculations if the diffuse approximation is accurate enough. It is suitable for fast and thermal reactor core calculations and for shield calculations. It is assumed the reader is familiar with the older, two-dimensional code SNAP and can refer to the report [TRG-Report-1990], describing it. The present report concentrates on the enhancements to SNAP that have been made to produce the three-dimensional version, SNAP-3D, and is intended to act a a guide on data preparation until a single, comprehensive report can be published. (author)

Rigid registration of CT, MR and cryosection images using a GLCM framework

DEFF Research Database (Denmark)

Bro-Nielsen, Morten; Grimson, E.; Mosges, R.

1997-01-01

The majority of the available rigid registration measures are based on a 2-dimensional histogram of corresponding grey-values in the registered images. This paper shows that these features are similar to a family of texture measures based on grey level co-occurrence matrices (GLCM). Features from...

Rigid multibody system dynamics with uncertain rigid bodies

Energy Technology Data Exchange (ETDEWEB)

Batou, A., E-mail: anas.batou@univ-paris-est.fr; Soize, C., E-mail: christian.soize@univ-paris-est.fr [Universite Paris-Est, Laboratoire Modelisation et Simulation Multi Echelle, MSME UMR 8208 CNRS (France)

2012-03-15

This paper is devoted to the construction of a probabilistic model of uncertain rigid bodies for multibody system dynamics. We first construct a stochastic model of an uncertain rigid body by replacing the mass, the center of mass, and the tensor of inertia by random variables. The prior probability distributions of the stochastic model are constructed using the maximum entropy principle under the constraints defined by the available information. The generators of independent realizations corresponding to the prior probability distribution of these random quantities are further developed. Then several uncertain rigid bodies can be linked to each other in order to calculate the random response of a multibody dynamical system. An application is proposed to illustrate the theoretical development.

On boundary conditions in three-dimensional AdS gravity

Energy Technology Data Exchange (ETDEWEB)

Miskovic, Olivera [Instituto de Fisica, P. Universidad Catolica de Valparaiso, Casilla 4059, Valparaiso (Chile) and Departamento de Fisica, P. Universidad Catolica de Chile, Casilla 306, Santiago 22 (Chile)]. E-mail: olivera.miskovic@ucv.cl; Olea, Rodrigo [Departamento de Fisica, P. Universidad Catolica de Chile, Casilla 306, Santiago 22 (Chile) and Centro Multidisciplinar de Astrofisica, CENTRA, Departamento de Fisica, Instituto Superior Tecnico, Universidade Tecnica de Lisboa, Av. Rovisco Pais 1, 1049-001 Lisbon (Portugal)]. E-mail: rolea@fisica.ist.utl.pt

2006-09-07

A finite action principle for three-dimensional gravity with negative cosmological constant, based on a boundary condition for the asymptotic extrinsic curvature, is considered. The bulk action appears naturally supplemented by a boundary term that is one half the Gibbons-Hawking term, that makes the Euclidean action and the Noether charges finite without additional Dirichlet counterterms. The consistency of this boundary condition with the Dirichlet problem in AdS gravity and the Chern-Simons formulation in three dimensions, and its suitability for the higher odd-dimensional case, are also discussed.

Three-Dimensional Organization of Chromosome Territories in the Human Interphase Nucleus

NARCIS (Netherlands)

T.A. Knoch (Tobias); J. Langowski (Jörg)

1999-01-01

textabstractDespite the successful linear sequencing of the human genome its three-dimensional structure is widely unknown. The regulation of genes has been shown to be connected closely to the three-dimensional organization of the genome in the cell nucleus. The nucleus of the cell has for a long

Interplay between cellular activity and three-dimensional scaffold-cell constructs with different foam structure processed by electron beam melting.

Science.gov (United States)

Nune, Krishna C; Misra, R Devesh K; Gaytan, Sara M; Murr, Lawrence E

2015-05-01

The cellular activity, biological response, and consequent integration of scaffold-cell construct in the physiological system are governed by the ability of cells to adhere, proliferate, and biomineralize. In this regard, we combine cellular biology and materials science and engineering to fundamentally elucidate the interplay between cellular activity and interconnected three-dimensional foamed architecture obtained by a novel process of electron beam melting and computational tools. Furthermore, the organization of key proteins, notably, actin, vinclulin, and fibronectin, involved in cellular activity and biological functions and relationship with the structure was explored. The interconnected foamed structure with ligaments was favorable to cellular activity that includes cell attachment, proliferation, and differentiation. The primary rationale for favorable modulation of cellular functions is that the foamed structure provided a channel for migration and communication between cells leading to highly mineralized extracellular matrix (ECM) by the differentiating osteoblasts. The filopodial interaction amongst cells on the ligaments was a governing factor in the secretion of ECM, with consequent influence on maturation and mineralization. © 2014 Wiley Periodicals, Inc.

Three-dimensional face shape in Fabry disease

NARCIS (Netherlands)

Cox-Brinkman, Josanne; Vedder, Anouk; Hollak, Carla; Richfield, Linda; Mehta, Atul; Orteu, Kate; Wijburg, Frits; Hammond, Peter

2007-01-01

Facial dysmorphology is an important feature in several lysosomal storage disorders. Although in Fabry disease facial dysmorphism is not a prominent sign, minor facial abnormalities have been previously reported. By analysing three-dimensional images of faces, we quantified facial dysmorphology in a

Topology of Flow Separation on Three-Dimensional Bodies

Science.gov (United States)

Chapman, Gary T.; Yates, Leslie A.

1991-01-01

In recent years there has been extensive research on three-dimensional flow separation. There are two different approaches: the phenomenological approach and a mathematical approach using topology. These two approaches are reviewed briefly and the shortcomings of some of the past works are discussed. A comprehensive approach applicable to incompressible and compressible steady-state flows as well as incompressible unsteady flow is then presented. The approach is similar to earlier topological approaches to separation but is more complete and in some cases adds more emphasis to certain points than in the past. To assist in the classification of various types of flow, nomenclature is introduced to describe the skin-friction portraits on the surface. This method of classification is then demonstrated on several categories of flow to illustrate particular points as well as the diversity of flow separation. The categories include attached, two-dimensional separation and three different types of simple, three-dimensional primary separation, secondary separation, and compound separation. Hypothetical experiments are utilized to illustrate the topological terminology and its role in characterizing these flows. These hypothetical experiments use colored oil injected onto the surface at singular points in the skin-friction portrait. Actual flow-visualization information, if available, is used to corroborate the hypothetical examples.

Source of errors and accuracy of a two-dimensional/three-dimensional fusion road map for endovascular aneurysm repair of abdominal aortic aneurysm.

Science.gov (United States)

Kauffmann, Claude; Douane, Frédéric; Therasse, Eric; Lessard, Simon; Elkouri, Stephane; Gilbert, Patrick; Beaudoin, Nathalie; Pfister, Marcus; Blair, Jean François; Soulez, Gilles

2015-04-01

To evaluate the accuracy and source of errors using a two-dimensional (2D)/three-dimensional (3D) fusion road map for endovascular aneurysm repair (EVAR) of abdominal aortic aneurysm. A rigid 2D/3D road map was tested in 16 patients undergoing EVAR. After 3D/3D manual registration of preoperative multidetector computed tomography (CT) and cone beam CT, abdominal aortic aneurysm outlines were overlaid on live fluoroscopy/digital subtraction angiography (DSA). Patient motion was evaluated using bone landmarks. The misregistration of renal and internal iliac arteries were estimated by 3 readers along head-feet and right-left coordinates (z-axis and x-axis, respectively) before and after bone and DSA corrections centered on the lowest renal artery. Iliac deformation was evaluated by comparing centerlines before and during intervention. A score of clinical added value was estimated as high (z-axis 5 mm). Interobserver reproducibility was calculated by the intraclass correlation coefficient. The lowest renal artery misregistration was estimated at x-axis = 10.6 mm ± 11.1 and z-axis = 7.4 mm ± 5.3 before correction and at x-axis = 3.5 mm ± 2.5 and z-axis = 4.6 mm ± 3.7 after bone correction (P = .08), and at 0 after DSA correction (P artery was estimated at x-axis = 2.4 mm ± 2.0 and z-axis = 2.2 mm ± 2.0. Score of clinical added value was low (n = 11), good (n= 0), and high (n= 5) before correction and low (n = 5), good (n = 4), and high (n = 7) after bone correction. Interobserver intraclass correlation coefficient for misregistration measurements was estimated at 0.99. Patient motion before stent graft delivery was estimated at x-axis = 8 mm ± 5.8 and z-axis = 3.0 mm ± 2.7. The internal iliac artery misregistration measurements were estimated at x-axis = 6.1 mm ± 3.5 and z-axis = 5.6 mm ± 4.0, and iliac centerline deformation was estimated at 38.3 mm ± 15.6. Rigid registration is feasible and fairly accurate. Only a partial reduction of vascular

Tag gas burnup based on three-dimensional FTR analysis

International Nuclear Information System (INIS)

Kidman, R.B.

1976-01-01

Flux spectra from a three-dimensional diffusion theory analysis of the Fast Test Reactor (FTR) are used to predict gas tag ratio changes, as a function of exposure, for each FTR fuel and absorber subassembly plenum. These flux spectra are also used to predict Xe-125 equilibrium activities in absorber plena in order to assess the feasibility of using Xe-125 gamma rays to detect and distinguish control rod failures from fuel rod failures. Worst case tag burnup changes are used in conjunction with burnup and mass spectrometer uncertainties to establish the minimum spacing of tags which allows the tags to be unambiguously identified

A comparative study of three-dimensional reconstructive images of temporomandibular joint using computed tomogram

International Nuclear Information System (INIS)

Lim, Suk Young; Koh, Kwang Joon

1993-01-01

The purpose of this study was to clarify the spatial relationship of temporomandibular joint and to an aid in the diagnosis of temporomandibular disorder. For this study, three-dimensional images of normal temporomandibular joint were reconstructed by computer image analysis system and three-dimensional reconstructive program integrated in computed tomography. The obtained results were as follows : 1. Two-dimensional computed tomograms had the better resolution than three dimensional computed tomograms in the evaluation of bone structure and the disk of TMJ. 2. Direct sagittal computed tomograms and coronal computed tomograms had the better resolution in the evaluation of the disk of TMJ. 3. The positional relationship of the disk could be visualized, but the configuration of the disk could not be clearly visualized on three-dimensional reconstructive CT images. 4. Three-dimensional reconstructive CT images had the smoother margin than three-dimensional images reconstructed by computer image analysis system, but the images of the latter had the better perspective. 5. Three-dimensional reconstructive images had the better spatial relationship of the TMJ articulation, and the joint space were more clearly visualized on dissection images.

FLEXURAL STRESS ANALYSIS OF RIGID PAVEMENTS USING AXI-SYMMETRIC AND PLANE STRAIN FEM

Directory of Open Access Journals (Sweden)

V.A. Sawant

2017-11-01

Full Text Available The design of pavement involves a study of soils and paving materials, their response under load for different climatic conditions. In the present study, an attempt has been made to compare stresses predicted using two finite element analyses. First analysis is based on the twodimensional plane strain assumption where as in second approach axi-symmetric condition is assumed to consider three-dimensional behavior of rigid pavement. The results are compared with flexural stresses obtained from conventional Portland Cement Association method. The computed flexural stresses obtained from axi-symmetric condition are found to be in close agreement with PCA method. Results of plane strain analysis show a fair agreement after application of an appropriate multiplication factor

Analytical Prediction of Three Dimensional Chatter Stability in Milling

Science.gov (United States)

Altintas, Yusuf

The chip regeneration mechanism during chatter is influenced by vibrations in three directions when milling cutters with ball end, bull nose, or inclined cutting edges are used. A three dimensional chatter stability is modeled analytically in this article. The dynamic milling system is formulated as a function of cutter geometry, the frequency response of the machine tool structure at the cutting zone in three Cartesian directions, cutter engagement conditions and material property. The dynamic milling system with nonlinearities and periodic delayed differential equations is reduced to a three dimensional linear stability problem by approximations based on the physics of milling. The chatter stability lobes are predicted in the frequency domain using the proposed analytical solution, and verified experimentally in milling a Titanium alloy with a face milling cutter having circular inserts.

Akinetic-rigid and tremor-dominant Parkinson's disease patients show different patterns of intrinsic brain activity.

Science.gov (United States)

Zhang, Jiuquan; Wei, Luqing; Hu, Xiaofei; Xie, Bing; Zhang, Yanling; Wu, Guo-Rong; Wang, Jian

2015-01-01

Parkinson's disease (PD) is a surprisingly heterogeneous neurodegenerative disorder. It is well established that different subtypes of PD present with different clinical courses and prognoses. However, the neural mechanism underlying these disparate presentations is uncertain. Here we used resting-state fMRI (rs-fMRI) and the regional homogeneity (ReHo) method to determine neural activity patterns in the two main clinical subgroups of PD (akinetic-rigid and tremor-dominant). Compared with healthy controls, akinetic-rigid (AR) subjects had increased ReHo mainly in right amygdala, left putamen, bilateral angular gyrus, bilateral medial prefrontal cortex (MPFC), and decreased ReHo in left post cingulate gyrus/precuneus (PCC/PCu) and bilateral thalamus. In contrast, tremor-dominant (TD) patients showed higher ReHo mostly in bilateral angular gyrus, left PCC, cerebellum_crus1, and cerebellum_6, while ReHo was decreased in right putamen, primary sensory cortex (S1), vermis_3, and cerebellum_4_5. These results indicate that AR and TD subgroups both represent altered spontaneous neural activity in default-mode regions and striatum, and AR subjects exhibit more changed neural activity in the mesolimbic cortex (amygdala) but TD in the cerebellar regions. Of note, direct comparison of the two subgroups revealed a distinct ReHo pattern primarily located in the striatal-thalamo-cortical (STC) and cerebello-thalamo-cortical (CTC) loops. Overall, our findings highlight the involvement of default mode network (DMN) and STC circuit both in AR and TD subtypes, but also underscore the importance of integrating mesolimbic-striatal and CTC loops in understanding neural systems of akinesia and rigidity, as well as resting tremor in PD. This study provides improved understanding of the pathophysiological models of different subtypes of PD. Copyright © 2014 Elsevier Ltd. All rights reserved.

Effect of trapezius muscle strength on three-dimensional scapular kinematics

OpenAIRE

Turgut, Elif; Duzgun, Irem; Baltaci, Gul

2016-01-01

[Purpose] This study aimed to investigate the effect of trapezius muscle isometric strength on three-dimensional scapular kinematics in asymptomatic shoulders. [Subjects and Methods] Thirty asymptomatic subjects were included to the study. Isometric strengths of the upper, middle, and lower trapezius muscle were measured using a handheld dynamometer. Three-dimensional scapular kinematics was recorded by an electromagnetic tracking device during frontal and sagittal plane elevation. For each m...

Evaluation for rigidity of box construction of nuclear reactor building

International Nuclear Information System (INIS)

Yamakawa, Tetsuo

1979-01-01

A huge box-shaped structure (hereafter, called box construction) of reinforced concrete is presently utilized as the reactor building structure in nuclear power plants. Evaluation of the rigidity of the huge box construction is required for making a vibration analysis model of nuclear reactor buildings. It is necessary to handle the box construction as the plates to which the force in plane is applied. This paper describes that the bending theory in elementary beam theory is equivalent to a peculiar, orthogonally anisotropic plate, the shearing rigidity and film rigidity in y direction of which are put to infinity and the Poisson's ratio is put to zero, viewed from the two-dimensional theory of elasticity. The form factor of 1.2 for shearing deformation in rectangular cross section was calculated from the parabolic distribution of shearing stress intensity, and it is the maximum value. The factor is equal to 1.2 for slender beams, but smaller than 1.2 for short and thick beams, having tendency to converge to 1.0. The non-conformity of boundary conditions regarding the shearing force at the both ends of cantilevers does not affect very seriously the evaluation of shearing rigidity. From the above results, it was found that the application of the theory to the box construction was able to give the rigidity evaluation with sufficient engineering accuracy. The theory can also be applied to the evaluation of tube type ultrahigh buildings. (Wakatsuki, Y.)

A multibody motorcycle model with rigid-ring tyres: formulation and validation

Science.gov (United States)

Leonelli, Luca; Mancinelli, Nicolò

2015-06-01

The aim of this paper is the development and validation of a three-dimensional multibody motorcycle model including a rigid-ring tyre model, taking into account both the slopes and elevation of the road surface. In order to achieve accurate assessment of ride and handling performances of a road racing motorcycle, a tyre model capable of reproducing the dynamic response to actual road excitation is required. While a number of vehicle models with such feature are available for car application, the extension to the motorcycle modelling has not been addressed yet. To do so, a novel parametrisation for the general motorcycle kinematics is proposed, using a mixed reference point and relative coordinates approach. The resulting description, developed in terms of dependent coordinates, makes it possible to include the rigid-ring kinematics as well as road elevation and slopes, without affecting computational efficiency. The equations of motion for the whole multibody system are derived symbolically and the constraint equations arising from the dependent coordinate formulation are handled using the position and velocity vector projection technique. The resulting system of equations is integrated in time domain using a standard ordinary differential equation (ODE) algorithm. Finally, the model is validated with respect to experimentally measured data in both time and frequency domains.

Three-dimensional imaging of hidden objects using positron emission backscatter

International Nuclear Information System (INIS)

Lee, Dongwon; Cowee, Misa; Fenimore, Ed; Galassi, Mark; Looker, Quinn; Mcneil, Wendy V.; Stonehill, Laura; Wallace, Mark

2009-01-01

Positron emission backscatter imaging is a technique for interrogation and three-dimensional (3-D) reconstruction of hidden objects when we only have access to the objects from one side. Using time-of-flight differences in detected direct and backscattered positron-emitted photons, we construct 3-D images of target objects. Recently at Los Alamos National Laboratory, a fully three-dimensional imaging system has been built and the experimental results are discussed in this paper. Quantitative analysis of images reconstructed in both two- and three-dimensions are also presented.

Development of seismic design method for piping system supported by elastoplastic damper. 3. Vibration test of three-dimensional piping model and its response analysis

International Nuclear Information System (INIS)

Namita, Yoshio; Kawahata, Jun-ichi; Ichihashi, Ichiro; Fukuda, Toshihiko.

1995-01-01

Component and piping systems in current nuclear power plants and chemical plants are designed to employ many supports to maintain safety and reliability against earthquakes. However, these supports are rigid and have a slight energy-dissipating effect. It is well known that applying high-damping supports to the piping system is very effective for reducing the seismic response. In this study, we investigated the design method of the elastoplastic damper [energy absorber (EAB)] and the seismic design method for a piping system supported by the EAB. Our final goal is to develop technology for applying the EAB to the piping system of an actual plant. In this paper, the vibration test results of the three-dimensional piping model are presented. From the test results, it is confirmed that EAB has a large energy-dissipating effect and is effective in reducing the seismic response of the piping system, and that the seismic design method for the piping system, which is the response spectrum mode superposition method using each modal damping and requires iterative calculation of EAB displacement, is applicable for the three-dimensional piping model. (author)

Three-dimensional lagrangian approach to the classical relativistic dynamics of directly interacting particles

International Nuclear Information System (INIS)

Gaida, R.P.; Kluchkousky, Ya.B.; Tretyak, V.I.

1987-01-01

In the present report the main attention is paid to the interrelations of various three-dimensional approaches and to the relation of the latter to the Fokker-type action formalism; the problem of the correspondence between three-dimensional descriptions and singular Lagrangian formalism will be shortly concerned. The authors start with the three-dimensional Lagrangian formulation of the classical RDIT. The generality of this formalism enables, similarly as in the non-relativistic case, to consider it as a central link explaining naturally a number of features of other three-dimensional approaches, namely Newtonian (based directly on second order equations of motion) and Hamiltonian ones). It is also capable of describing four-dimensional manifestly covariant models using Fokker action integrals and singular Lagrangians

Three-Dimensional Soil Landscape Modeling: A Potential Earth Science Teaching Tool

Science.gov (United States)

Schmid, Brian M.; Manu, Andrew; Norton, Amy E.

2009-01-01

Three-dimensional visualization is helpful in understanding soils, and three dimensional (3-D) tools are gaining popularity in teaching earth sciences. Those tools are still somewhat underused in soil science, yet soil properties such as texture, color, and organic carbon content vary both vertically and horizontally across the landscape. These…

A novel three dimensional semimetallic MoS{sub 2}

Energy Technology Data Exchange (ETDEWEB)

Tang, Zhen-Kun [Beijing Computational Science Research Center, Beijing 100084 (China); Departments of Physics and Electronics, Hengyang Normal University, Hengyang 421008 (China); Zhang, Hui; Liu, Li-Min, E-mail: limin.liu@csrc.ac.cn [Beijing Computational Science Research Center, Beijing 100084 (China); Liu, Hao [Chengdu Green Energy and Green Manufacturing Technology R and D Center, Chengdu, Sichuan 610207 (China); Lau, Woon-Ming [Beijing Computational Science Research Center, Beijing 100084 (China); Chengdu Green Energy and Green Manufacturing Technology R and D Center, Chengdu, Sichuan 610207 (China)

2014-05-28

Transition metal dichalcogenides (TMDs) have many potential applications, while the performances of TMDs are generally limited by the less surface active sites and the poor electron transport efficiency. Here, a novel three-dimensional (3D) structure of molybdenum disulfide (MoS{sub 2}) with larger surface area was proposed based on first-principle calculations. 3D layered MoS{sub 2} structure contains the basal surface and joint zone between the different nanoribbons, which is thermodynamically stable at room temperature, as confirmed by first principles molecular dynamics calculations. Compared the two-dimensional layered structures, the 3D MoS{sub 2} not only owns the large surface areas but also can effectively avoid the aggregation. Interestingly, although the basal surface remains the property of the intrinsic semiconductor as the bulk MoS{sub 2}, the joint zone of 3D MoS{sub 2} exhibits semimetallic, which is derived from degenerate 3d orbitals of the Mo atoms. The high stability, large surface area, and high conductivity make 3D MoS{sub 2} have great potentials as high performance catalyst.

Three dimensional electrochemical system for neurobiological studies

DEFF Research Database (Denmark)

Vazquez, Patricia; Dimaki, Maria; Svendsen, Winnie Edith

2009-01-01

In this work we report a novel three dimensional electrode array for electrochemical measurements in neuronal studies. The main advantage of working with these out-of-plane structures is the enhanced sensitivity of the system in terms of measuring electrochemical changes in the environment...

Three-dimensional concentration of light in deeply sub-wavelength, laterally tapered gap-plasmon nanocavities

Energy Technology Data Exchange (ETDEWEB)

Tagliabue, Giulia [Laboratory of Thermodynamics in Emerging Technologies, ETH Zurich, Zurich 8092 (Switzerland); Thomas J. Watson, Sr. Laboratories of Applied Physics, California Institute of Technology, Pasadena, California 91125 (United States); Poulikakos, Dimos; Eghlidi, Hadi, E-mail: eghlidim@ethz.ch [Laboratory of Thermodynamics in Emerging Technologies, ETH Zurich, Zurich 8092 (Switzerland)

2016-05-30

Gap-plasmons (GP) in metal-insulator-metal (MIM) structures have shown exceptional performance in guiding and concentrating light within deep subwavelength layers. Reported designs to date exploit tapered thicknesses of the insulating layer in order to confine and focus the GP mode. Here, we propose a mechanism for the three dimensional concentration of light in planar MIM structures which exploits exclusively the lateral tapering of the front metallic layer while keeping a constant thickness of the insulating layer. We demonstrate that an array of tapered planar GP nanocavities can efficiently concentrate light in all three dimensions. A semi-analytical, one-dimensional model provides understanding of the underlying physics and approximately predicts the behavior of the structure. Three-dimensional simulations are then used to precisely calculate the optical behavior. Cavities with effective volumes as small as 10{sup −5} λ{sup 3} are achieved in an ultrathin MIM configuration. Our design is inherently capable of efficiently coupling with free-space radiation. In addition, being composed of two electrically continuous layers separated by an ultrathin dielectric spacer, it could find interesting applications in the area of active metamaterials or plasmonic photocatalysis where both electrical access and light concentration are required.

Three dimensional characterization and archiving system

International Nuclear Information System (INIS)

Sebastian, R.L.; Clark, R.; Gallman, P.

1995-01-01

The Three Dimensional Characterization and Archiving System (3D-ICAS) is being developed as a remote system to perform rapid in situ analysis of hazardous organics and radionuclide contamination on structural materials. Coleman Research and its subcontractors, Thermedics Detection, Inc. (TD) and the University of Idaho (UI) are in the second phase of a three phase program to develop 3D-ICAS to support Decontamination and Decommissioning (D ampersand D) operations. Accurate physical characterization of surfaces and the radioactive and organic is a critical D ampersand D task. Surface characterization includes identification of potentially dangerous inorganic materials, such as asbestos and transite. Real-time remotely operable characterization instrumentation will significantly advance the analysis capabilities beyond those currently employed. Chemical analysis is a primary area where the characterization process will be improved. Chemical analysis plays a vital role throughout the process of decontamination. Before clean-up operations can begin the site must be characterized with respect to the type and concentration of contaminants, and detailed site mapping must clarify areas of both high and low risk. During remediation activities chemical analysis provides a means to measure progress and to adjust clean-up strategy. Once the clean-up process has been completed the results of chemical analysis will verify that the site is in compliance with federal and local regulations

Comparison of two three-dimensional cephalometric analysis computer software.

Science.gov (United States)

Sawchuk, Dena; Alhadlaq, Adel; Alkhadra, Thamer; Carlyle, Terry D; Kusnoto, Budi; El-Bialy, Tarek

2014-10-01

Three-dimensional cephalometric analyses are getting more attraction in orthodontics. The aim of this study was to compare two softwares to evaluate three-dimensional cephalometric analyses of orthodontic treatment outcomes. Twenty cone beam computed tomography images were obtained using i-CAT(®) imaging system from patient's records as part of their regular orthodontic records. The images were analyzed using InVivoDental5.0 (Anatomage Inc.) and 3DCeph™ (University of Illinois at Chicago, Chicago, IL, USA) software. Before and after orthodontic treatments data were analyzed using t-test. Reliability test using interclass correlation coefficient was stronger for InVivoDental5.0 (0.83-0.98) compared with 3DCeph™ (0.51-0.90). Paired t-test comparison of the two softwares shows no statistical significant difference in the measurements made in the two softwares. InVivoDental5.0 measurements are more reproducible and user friendly when compared to 3DCeph™. No statistical difference between the two softwares in linear or angular measurements. 3DCeph™ is more time-consuming in performing three-dimensional analysis compared with InVivoDental5.0.

Three-dimensional volumetric display by inclined-plane scanning

Science.gov (United States)

Miyazaki, Daisuke; Eto, Takuma; Nishimura, Yasuhiro; Matsushita, Kenji

2003-05-01

A volumetric display system based on three-dimensional (3-D) scanning that uses an inclined two-dimensional (2-D) image is described. In the volumetric display system a 2-D display unit is placed obliquely in an imaging system into which a rotating mirror is inserted. When the mirror is rotated, the inclined 2-D image is moved laterally. A locus of the moving image can be observed by persistence of vision as a result of the high-speed rotation of the mirror. Inclined cross-sectional images of an object are displayed on the display unit in accordance with the position of the image plane to observe a 3-D image of the object by persistence of vision. Three-dimensional images formed by this display system satisfy all the criteria for stereoscopic vision. We constructed the volumetric display systems using a galvanometer mirror and a vector-scan display unit. In addition, we constructed a real-time 3-D measurement system based on a light section method. Measured 3-D images can be reconstructed in the 3-D display system in real time.

Study of fission dynamics with the three-dimensional Langevin equations

Energy Technology Data Exchange (ETDEWEB)

Eslamizadeh, H. [Persian Gulf University, Department of Physics, Bushehr (Iran, Islamic Republic of)

2011-11-15

The dynamics of fission has been studied by solving one- and three-dimensional Langevin equations with dissipation generated through the chaos weighted wall and window friction formula. The average prescission neutron multiplicities, fission probabilities and the mean fission times have been calculated in a broad range of the excitation energy for compound nuclei {sup 210}Po and {sup 224}Th formed in the fusion-fission reactions {sup 4}He+{sup 206}Pb, {sup 16}O+{sup 208}Pb and results compared with the experimental data. The analysis of the results shows that the average prescission neutron multiplicities, fission probabilities and the mean fission times calculated by one- and three-dimensional Langevin equations are different from each other, and also the results obtained based on three-dimensional Langevin equations are in better agreement with the experimental data. (orig.)

Quantum field between moving mirrors: A three dimensional example

Science.gov (United States)

Hacyan, S.; Jauregui, Roco; Villarreal, Carlos

1995-01-01

The scalar quantum field uniformly moving plates in three dimensional space is studied. Field equations for Dirichlet boundary conditions are solved exactly. Comparison of the resulting wavefunctions with their instantaneous static counterpart is performed via Bogolubov coefficients. Unlike the one dimensional problem, 'particle' creation as well as squeezing may occur. The time dependent Casimir energy is also evaluated.

Direct Linear Transformation Method for Three-Dimensional Cinematography

Science.gov (United States)

Shapiro, Robert

1978-01-01

The ability of Direct Linear Transformation Method for three-dimensional cinematography to locate points in space was shown to meet the accuracy requirements associated with research on human movement. (JD)

Three-dimensional MR imaging of the cerebrospinal system with the RARE technique

International Nuclear Information System (INIS)

Hennig, J.; Ott, D.; Ylayasski, J.

1987-01-01

Three-dimensional RARE myelography is a fast technique for high-resolution imaging of the cerebrospinal fluid. A data set with 1 x 1 x 1-mm resolution can be generated with a 12-minute acquisition time. Sophisticated three-dimensional display algorithms allow reconstruction of planes at arbitrary angles and full three-dimensional displays, which yield extremely useful information for neurosurgical planning. Additionally, the injection of contrast agent can be simulated on the computer and communication pathways between structures of interest can be found noninvasively

Extinction cross-section cancellation of a cylindrical radiating active source near a rigid corner and acoustic invisibility

Science.gov (United States)

Mitri, F. G.

2017-11-01

Active cloaking in its basic form requires that the extinction cross-section (or energy efficiency) from a radiating body vanishes. In this analysis, this physical effect is demonstrated for an active cylindrically radiating acoustic source in a non-viscous fluid, undergoing periodic axisymmetric harmonic vibrations near a rigid corner (i.e., quarter-space). The rigorous multipole expansion method in cylindrical coordinates, the method of images, and the addition theorem of cylindrical wave functions are used to derive closed-form mathematical expressions for the radiating, amplification, and extinction cross-sections of the active source. Numerical computations are performed assuming monopole and dipole modal oscillations of the circular source. The results reveal some of the situations where the extinction energy efficiency factor of the active source vanishes depending on its size and location with respect to the rigid corner, thus, achieving total invisibility. Moreover, the extinction energy efficiency factor varies between positive or negative values. These effects also occur for higher-order modal oscillations of the active source. The results find potential applications in the development of acoustic cloaking devices and invisibility in underwater acoustics or other areas.

Quasi-three-dimensional particle imaging with digital holography.

Science.gov (United States)

Kemppinen, Osku; Heinson, Yuli; Berg, Matthew

2017-05-01

In this work, approximate three-dimensional structures of microparticles are generated with digital holography using an automated focus method. This is done by stacking a collection of silhouette-like images of a particle reconstructed from a single in-line hologram. The method enables estimation of the particle size in the longitudinal and transverse dimensions. Using the discrete dipole approximation, the method is tested computationally by simulating holograms for a variety of particles and attempting to reconstruct the known three-dimensional structure. It is found that poor longitudinal resolution strongly perturbs the reconstructed structure, yet the method does provide an approximate sense for the structure's longitudinal dimension. The method is then applied to laboratory measurements of holograms of single microparticles and their scattering patterns.

Three-dimensional P velocity structure in Beijing area

Science.gov (United States)

Yu, Xiang-Wei; Chen, Yun-Tai; Wang, Pei-De

2003-01-01

A detail three-dimensional P wave velocity structure of Beijing, Tianjin and Tangshan area (BTT area) was determined by inverting local earthquake data. In total 16 048 P wave first arrival times from 16048 shallow and mid-depth crustal earthquakes, which occurred in and around the BTT area from 1992 to 1999 were used. The first arrival times are recorded by Northern China United Telemetry Seismic Network and Yanqing-Huailai Digital Seismic Network. Hypocentral parameters of 1 132 earthquakes with magnitude M L=1.7 6.2 and the three-dimensional P wave velocity structure were obtained simultaneously. The inversion result reveals the complicated lateral heterogeneity of P wave velocity structure around BTT area. The tomographic images obtained are also found to explain other seismological observations well.

Three-dimensional MR imaging of congenital heart disease

International Nuclear Information System (INIS)

Laschinger, J.C.; Vannier, M.W.; Knapp, R.H.; Gutierrez, F.R.; Cox, J.L.

1987-01-01

Contiguous 5-mm thick ECG-gated MR images of the thorax were edited using surface reconstruction techniques to produce three-dimensional (3D) images of the heart and great vessels in four healthy individuals and 25 patients with congenital heart disease (aged 3 months-30 years). Anomalies studied include atrial and ventricular septal defects, aortic coarctation, AV canal defects, double outlet ventricles, hypoplastic left heart syndrome, and a wide spectrum of patients with tetralogy of Fallot. The results were correlated with echocardiographic and cineradiographic studies, and with surgical findings or pathologic specimens. Three-dimensional reconstructions accurately localized the dimensions and locations of all cardiac and great vessel anomalies and often displayed anatomic findings not diagnosed or visualized with other forms of diagnostic imaging

On the size distribution of one-, two- and three-dimensional Voronoi cells

International Nuclear Information System (INIS)

Marthinsen, K.

1994-03-01

The present report gives a presentation of the different cell size distribution obtained by computer simulations of random Voronoi cell structures in one-, two- and three-dimensional space. The random Voronoi cells are constructed from cell centroids randomly distributed along a string, in the plane and in three-dimensional space, respectively. The size distributions are based on 2-3 · 10 4 cells. For the spacial polyhedra both the distribution of volumes, areas and radii are presented, and the two latter quantities are compared to the distributions of areas and radii from a planar section through the three-dimensional structure as well as to the corresponding distributions obtained from a pure two-dimensional cell structure. 11 refs., 11 figs

Three-dimensional versus two-dimensional vision in laparoscopy

DEFF Research Database (Denmark)

Sørensen, Stine D; Savran, Mona Meral; Konge, Lars

2016-01-01

were cohort size and characteristics, skill trained or operation performed, instrument used, outcome measures, and conclusions. Two independent authors performed the search and data extraction. RESULTS: Three hundred and forty articles were screened for eligibility, and 31 RCTs were included...... through a two-dimensional (2D) projection on a monitor, which results in loss of depth perception. To counter this problem, 3D imaging for laparoscopy was developed. A systematic review of the literature was performed to assess the effect of 3D laparoscopy. METHODS: A systematic search of the literature...... in the review. Three trials were carried out in a clinical setting, and 28 trials used a simulated setting. Time was used as an outcome measure in all of the trials, and number of errors was used in 19 out of 31 trials. Twenty-two out of 31 trials (71 %) showed a reduction in performance time, and 12 out of 19...

Transverse mixing in three-dimensional nonstationary anisotropic heterogeneous porous media

DEFF Research Database (Denmark)

Cirpka, Olaf; Chiogna, Gabriele; Rolle, Massimo

2015-01-01

-dimensional domains, more complex flow patterns are possible because streamlines can twist. In particular, spatially varying orientation of anisotropy can cause steady-state groundwater whirls. We analyze steady-state solute transport in three-dimensional locally isotropic heterogeneous porous media with blockwise...

Three-dimensional groundwater velocity field in an unconfined aquifer under irrigation

International Nuclear Information System (INIS)

Zlotnik, V.

1990-01-01

A method for three-dimensional flow velocity calculation has been developed to evaluate unconfined aquifer sensitivity to areal agricultural contamination of groundwater. The methodology of Polubarinova-Kochina is applied to an unconfined homogeneous compressible or incompressible anisotropic aquifer. It is based on a three-dimensional groundwater flow model with a boundary condition on the moving surface. Analytical solutions are obtained for a hydraulic head under the influence of areal sources of circular and rectangular shape using integral transforms. Two-dimensional Hantush formulas result from the vertical averaging of the three-dimensional solutions, and the asymptotic behavior of solutions is analyzed. Analytical expressions for flow velocity components are obtained from the gradient of the hydraulic head field. Areal and temporal variability of specific yield in groundwater recharge areas is also taken into account. As a consequence of linearization of the boundary condition, the operation of any irrigation system with respect to groundwater is represented by superposition of the operating wells and circular and rectangular source influences. Combining the obtained solutions with Dagan or Neuman well functions, one can develop computer codes for the analytical computation of the three-dimensional groundwater hydraulic head and velocity component distributions. Methods for practical implementation are discussed. (Author) (20 refs., 4 figs.)

Three-dimensional x-ray diffraction detection and visualization

International Nuclear Information System (INIS)

Allahkarami, Masoud; Hanan, Jay C

2014-01-01

A new method of sensing and analyzing three-dimensional (3D) x-ray diffraction (XRD) cones was introduced. Using a two-dimensional area detector, a sequence of frames was collected while moving the detector away from the sample with small equally spaced steps and keeping all other parameters constant. A 3D dataset was created from the subsequent frames. The 3D x-ray diffraction (XRD 3 ) pattern contains far more information than a one-dimensional profile collected with the conventional diffractometer and 2D x-ray diffraction (XRD 2 ). The present work discusses some fundamentals about XRD 3 , such as the data collection method, 3D visualization, diffraction data interpretation and potential applications of XRD 3 . (paper)

Integration of a semi-rigid proline ligand and 4,4'-bipyridine in the synthesis of homochiral metal-organic frameworks with helices.

Science.gov (United States)

Xu, Zhong-Xuan; Kang, Yao; Han, Min-Le; Li, Dong-Sheng; Zhang, Jian

2015-06-28

A pair of 3-D homochiral metal-organic frameworks (HMOFs) based on a mixed semi-rigid 5-(2-carboxypyrrolidine-1-carbonyl)isophthalate (PIA) ligand and rigid 4,4'-bipyridine (bipy), [Co3((R)-PIA)2(bipy)3]·6H2O (1-D) and [Co3((S)-PIA)2(bipy)3]·6H2O (1-L) are synthesized and structurally characterized. They are enantiomers and exhibit three-dimensional open frameworks. In each structure, the PIA ligands link the Co centers into homochiral frameworks with large open channels that are occupied by the bipy ligands. Interesting helical chains built from the connectivity between PIA ligands and Co centers are presented. Antiferromagnetic coupling is observed in 1-D. These results demonstrated that the mixed ligand approach is successful for the construction of HMOFs.

Three-dimensional dynamic hip contact area and pressure distribution during activities of daily living.

Science.gov (United States)

Yoshida, H; Faust, A; Wilckens, J; Kitagawa, M; Fetto, J; Chao, Edmund Y-S

2006-01-01

Estimation of the hip joint contact area and pressure distribution during activities of daily living is important in predicting joint degeneration mechanism, prosthetic implant wear, providing biomechanical rationales for preoperative planning and postoperative rehabilitation. These biomechanical data were estimated utilizing a generic hip model, the Discrete Element Analysis technique, and the in vivo hip joint contact force data. The three-dimensional joint potential contact area was obtained from the anteroposterior radiograph of a subject and the actual joint contact area and pressure distribution in eight activities of daily living were calculated. During fast, normal, and slow walking, the peak pressure of moderate magnitude was located at the lateral roof of the acetabulum during mid-stance. In standing up and sitting down, and during knee bending, the peak pressures were located at the edge of the posterior horn and the magnitude of the peak pressure during sitting down was 2.8 times that of normal walking. The peak pressure was found at the lateral roof in climbing up stairs which was higher than that in going down stairs. These results can be used to rationalize rehabilitation protocols, functional restrictions after complex acetabular reconstructions, and prosthetic component wear and fatigue test set up. The same model and analysis can provide further insight to soft tissue loading and pathology such as labral injury. When the pressure distribution on the acetabulum is inverted onto the femoral head, prediction of subchondral bone collapse associated with avascular necrosis can be achieved with improved accuracy.

Three-dimensional macroporous nanoelectronic networks as minimally invasive brain probes

Science.gov (United States)

Xie, Chong; Liu, Jia; Fu, Tian-Ming; Dai, Xiaochuan; Zhou, Wei; Lieber, Charles M.

2015-12-01

Direct electrical recording and stimulation of neural activity using micro-fabricated silicon and metal micro-wire probes have contributed extensively to basic neuroscience and therapeutic applications; however, the dimensional and mechanical mismatch of these probes with the brain tissue limits their stability in chronic implants and decreases the neuron-device contact. Here, we demonstrate the realization of a three-dimensional macroporous nanoelectronic brain probe that combines ultra-flexibility and subcellular feature sizes to overcome these limitations. Built-in strains controlling the local geometry of the macroporous devices are designed to optimize the neuron/probe interface and to promote integration with the brain tissue while introducing minimal mechanical perturbation. The ultra-flexible probes were implanted frozen into rodent brains and used to record multiplexed local field potentials and single-unit action potentials from the somatosensory cortex. Significantly, histology analysis revealed filling-in of neural tissue through the macroporous network and attractive neuron-probe interactions, consistent with long-term biocompatibility of the device.

Three-dimensional bioprinting of complex cell laden alginate hydrogel structures.

Science.gov (United States)

Tabriz, Atabak Ghanizadeh; Hermida, Miguel A; Leslie, Nicholas R; Shu, Wenmiao

2015-12-21

Different bioprinting techniques have been used to produce cell-laden alginate hydrogel structures, however these approaches have been limited to 2D or simple three-dimension (3D) structures. In this study, a new extrusion based bioprinting technique was developed to produce more complex alginate hydrogel structures. This was achieved by dividing the alginate hydrogel cross-linking process into three stages: primary calcium ion cross-linking for printability of the gel, secondary calcium cross-linking for rigidity of the alginate hydrogel immediately after printing and tertiary barium ion cross-linking for long-term stability of the alginate hydrogel in culture medium. Simple 3D structures including tubes were first printed to ensure the feasibility of the bioprinting technique and then complex 3D structures such as branched vascular structures were successfully printed. The static stiffness of the alginate hydrogel after printing was 20.18 ± 1.62 KPa which was rigid enough to sustain the integrity of the complex 3D alginate hydrogel structure during the printing. The addition of 60 mM barium chloride was found to significantly extend the stability of the cross-linked alginate hydrogel from 3 d to beyond 11 d without compromising the cellular viability. The results based on cell bioprinting suggested that viability of U87-MG cells was 93 ± 0.9% immediately after bioprinting and cell viability maintained above 88% ± 4.3% in the alginate hydrogel over the period of 11 d.

Three-dimensional flow and turbulence structure in electrostatic precipitator

DEFF Research Database (Denmark)

Ullum, Thorvald Uhrskov; Larsen, Poul Scheel; Özcan, Oktay

2002-01-01

Stereo PIV is employed to study the three-dimensional velocity and turbulence fields in a laboratory model of a negative corona, barbed-wire, smooth-plate, electrostatic precipitator (figure 1). The study is focused on determining the parametric effects of axial development, mean current density Jm...... and bulk velocity U0 on secondary flows and turbulence levels and structures due to the action of the three-dimensional electrostatic field on the charged gas. At constant bulk velocity (U0 = 1 m/s) and current density (Jm = 0.4 mA/m2), secondary flows in the form of rolls of axial vorticity with swirl...

Large three-dimensional photonic crystals based on monocrystalline liquid crystal blue phases.

Science.gov (United States)

Chen, Chun-Wei; Hou, Chien-Tsung; Li, Cheng-Chang; Jau, Hung-Chang; Wang, Chun-Ta; Hong, Ching-Lang; Guo, Duan-Yi; Wang, Cheng-Yu; Chiang, Sheng-Ping; Bunning, Timothy J; Khoo, Iam-Choon; Lin, Tsung-Hsien

2017-09-28

Although there have been intense efforts to fabricate large three-dimensional photonic crystals in order to realize their full potential, the technologies developed so far are still beset with various material processing and cost issues. Conventional top-down fabrications are costly and time-consuming, whereas natural self-assembly and bottom-up fabrications often result in high defect density and limited dimensions. Here we report the fabrication of extraordinarily large monocrystalline photonic crystals by controlling the self-assembly processes which occur in unique phases of liquid crystals that exhibit three-dimensional photonic-crystalline properties called liquid-crystal blue phases. In particular, we have developed a gradient-temperature technique that enables three-dimensional photonic crystals to grow to lateral dimensions of ~1 cm (~30,000 of unit cells) and thickness of ~100 μm (~ 300 unit cells). These giant single crystals exhibit extraordinarily sharp photonic bandgaps with high reflectivity, long-range periodicity in all dimensions and well-defined lattice orientation.Conventional fabrication approaches for large-size three-dimensional photonic crystals are problematic. By properly controlling the self-assembly processes, the authors report the fabrication of monocrystalline blue phase liquid crystals that exhibit three-dimensional photonic-crystalline properties.

Foundations of the theory of three-dimensional quadrupolar mass spectrometry. 1

International Nuclear Information System (INIS)

Sheretov, Eh.P.

1979-01-01

The basic principles of the theory of three-dimensional quadrupolar mass spectrometry are developed. It is shown that the ''stretching'' of the electrode system of the sensor of a three-dimensional quadrupolar mass spectrometer in the direction of an axis (introduction of the system assymetry) leads to a sharp decrease of the high-frequency field effect on the particle trajectory in this direction. Presented are ratios determining the configuration of electrode systems of sensors of flight-type quadrupolar mass spectrometers. Specific features of the stability diagram for such analyzers are discussed. It is shown that the property detected makes it possible to develop new promising time-of-flight three-dimensional quadrupolar mass spectrometers

Three-dimensional display techniques: description and critique of methods

International Nuclear Information System (INIS)

Budinger, T.F.

1982-01-01

The recent advances in non invasive medical imaging of 3 dimensional spatial distribution of radionuclides, X-ray attenuation coefficients, and nuclear magnetic resonance parameters necessitate development of a general method for displaying these data. The objective of this paper is to give a systematic description and comparison of known methods for displaying three dimensional data. The discussion of display methods is divided into two major categories: 1) computer-graphics methods which use a two dimensional display screen; and 2) optical methods (such as holography, stereopsis and vari-focal systems)

Integrated microchannel cooling in a three dimensional integrated circuit: A thermal management

Directory of Open Access Journals (Sweden)

Wang Kang-Jia

2016-01-01

Full Text Available Microchannel cooling is a promising technology for solving the three-dimensional integrated circuit thermal problems. However, the relationship between the microchannel cooling parameters and thermal behavior of the three dimensional integrated circuit is complex and difficult to understand. In this paper, we perform a detailed evaluation of the influence of the microchannel structure and the parameters of the cooling liquid on steady-state temperature profiles. The results presented in this paper are expected to aid in the development of thermal design guidelines for three dimensional integrated circuit with microchannel cooling.

Instantons, three-dimensional gauge theory, and the Atiyah-Hitchin manifold

NARCIS (Netherlands)

Dorey, N.; Khoze, V.V.; Mattis, M.P.; Tong, D.; Vandoren, S.

1997-01-01

We investigate quantum effects on the Coulomb branch of three-dimensional N = 4 supersymmetric gauge theory with gauge group SU(2). We calculate perturbative and one-instanton contributions to the Wilsonian effective action using standard weakcoupling methods. Unlike the four-dimensional case,

Three-dimensional echocardiographic assessment of atrial septal defects

Directory of Open Access Journals (Sweden)

Charles German

2015-01-01

Full Text Available Echocardiography provides a useful tool in the diagnosis of many congenital heart diseases, including atrial septal defects, and aids in further delineating treatment options. Although two-dimensional echocardiography has been the standard of care in this regard, technological advancements have made three-dimensional echocardiography possible, and the images obtained in this new imaging modality are able to accurately portray the morphology, location, dimensions, and dynamic changes of defects and many other heart structures during the cardiac cycle.

Three-dimensional coupled double-distribution-function lattice ...

Indian Academy of Sciences (India)

Ruo-Fan Qiu

2017-11-14

Nov 14, 2017 ... Abstract. Two three-dimensional (3D) lattice Boltzmann models in the framework of coupled double-distribution- function approach for compressible flows, in which specific-heat ratio and Prandtl number can be adjustable, are developed in this paper. The main differences between the two models are ...

Development of a Three-Dimensional Hand Model Using Three-Dimensional Stereophotogrammetry: Assessment of Image Reproducibility.

Directory of Open Access Journals (Sweden)

Inge A Hoevenaren

Full Text Available Using three-dimensional (3D stereophotogrammetry precise images and reconstructions of the human body can be produced. Over the last few years, this technique is mainly being developed in the field of maxillofacial reconstructive surgery, creating fusion images with computed tomography (CT data for precise planning and prediction of treatment outcome. Though, in hand surgery 3D stereophotogrammetry is not yet being used in clinical settings.A total of 34 three-dimensional hand photographs were analyzed to investigate the reproducibility. For every individual, 3D photographs were captured at two different time points (baseline T0 and one week later T1. Using two different registration methods, the reproducibility of the methods was analyzed. Furthermore, the differences between 3D photos of men and women were compared in a distance map as a first clinical pilot testing our registration method.The absolute mean registration error for the complete hand was 1.46 mm. This reduced to an error of 0.56 mm isolating the region to the palm of the hand. When comparing hands of both sexes, it was seen that the male hand was larger (broader base and longer fingers than the female hand.This study shows that 3D stereophotogrammetry can produce reproducible images of the hand without harmful side effects for the patient, so proving to be a reliable method for soft tissue analysis. Its potential use in everyday practice of hand surgery needs to be further explored.

Using Three-Dimensional Printing to Fabricate a Tubing Connector for Dilation and Evacuation.

Science.gov (United States)

Stitely, Michael L; Paterson, Helen

2016-02-01

This is a proof-of-concept study to show that simple instrumentation problems encountered in surgery can be solved by fabricating devices using a three-dimensional printer. The device used in the study is a simple tubing connector fashioned to connect two segments of suction tubing used in a surgical procedure where no commercially available product for this use is available through our usual suppliers in New Zealand. A cylindrical tubing connector was designed using three-dimensional printing design software. The tubing connector was fabricated using the Makerbot Replicator 2X three-dimensional printer. The connector was used in 15 second-trimester dilation and evacuation procedures. Data forms were completed by the primary operating surgeon. Descriptive statistics were used with the expectation that the device would function as intended in all cases. The three-dimensional printed tubing connector functioned as intended in all 15 instances. Commercially available three-dimensional printing technology can be used to overcome simple instrumentation problems encountered during gynecologic surgical procedures.

Mantle dynamics in Mars and Venus: Influence of an immobile lithosphere on three-dimensional mantle convection

International Nuclear Information System (INIS)

Schubert, G.; Bercovici; Glatzmaier, G.A.

1990-01-01

Numerical calculations of fully three-dimensional convection in constant viscosity, compressible spherical shells are interpreted in terms of possible convective motions in the mantles of Venus and Mars. The shells are heated both internally and from below to account for radiogenic heating, secular cooling, and heat flow from the core. The lower boundary of each of the shells is isothermal and shear stress free, as appropriate to the interface between a mantle and a liquid outer core. The upper boundary of each of the shells is rigid and isothermal, as appropriate to the base of a thick immobile lithosphere. Calculations with shear stress-free upper boundaries are also carried out to assess the role of the rigid surface condition. The ratio of the inner radius of each shell to its outer radius is in accordance with possible core sizes in both Venus and Mars. A calculation is also carried out for a Mars model with a small core to simulate mantle convection during early core formation. Different relative proportions of internal and bottom heating are investigated, ranging from nearly complete heating from within to almost all heating from below. The Rayleigh numbers of all the cases are approximately 100 times the critical Rayleigh numbers for the onset of convection. Cylindrical plumes are the prominent form of upwelling in the models independent of the surface boundary condition so long as sufficient heat derives from the core. Thus major volcanic centers on Mars, such as Tharsis and Elysium, and the coronae and some equatorial highlands on Venus may be the surface expressions of cylindrical mantle plumes

Do Three-dimensional Visualization and Three-dimensional Printing Improve Hepatic Segment Anatomy Teaching? A Randomized Controlled Study.

Science.gov (United States)

Kong, Xiangxue; Nie, Lanying; Zhang, Huijian; Wang, Zhanglin; Ye, Qiang; Tang, Lei; Li, Jianyi; Huang, Wenhua

2016-01-01

Hepatic segment anatomy is difficult for medical students to learn. Three-dimensional visualization (3DV) is a useful tool in anatomy teaching, but current models do not capture haptic qualities. However, three-dimensional printing (3DP) can produce highly accurate complex physical models. Therefore, in this study we aimed to develop a novel 3DP hepatic segment model and compare the teaching effectiveness of a 3DV model, a 3DP model, and a traditional anatomical atlas. A healthy candidate (female, 50-years old) was recruited and scanned with computed tomography. After three-dimensional (3D) reconstruction, the computed 3D images of the hepatic structures were obtained. The parenchyma model was divided into 8 hepatic segments to produce the 3DV hepatic segment model. The computed 3DP model was designed by removing the surrounding parenchyma and leaving the segmental partitions. Then, 6 experts evaluated the 3DV and 3DP models using a 5-point Likert scale. A randomized controlled trial was conducted to evaluate the educational effectiveness of these models compared with that of the traditional anatomical atlas. The 3DP model successfully displayed the hepatic segment structures with partitions. All experts agreed or strongly agreed that the 3D models provided good realism for anatomical instruction, with no significant differences between the 3DV and 3DP models in each index (p > 0.05). Additionally, the teaching effects show that the 3DV and 3DP models were significantly better than traditional anatomical atlas in the first and second examinations (p < 0.05). Between the first and second examinations, only the traditional method group had significant declines (p < 0.05). A novel 3DP hepatic segment model was successfully developed. Both the 3DV and 3DP models could improve anatomy teaching significantly. Copyright © 2015 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.

Calculations of critical micelle concentration by dissipative particle dynamics simulations: the role of chain rigidity.

Science.gov (United States)

Lee, Ming-Tsung; Vishnyakov, Aleksey; Neimark, Alexander V

2013-09-05

Micelle formation in surfactant solutions is a self-assembly process governed by complex interplay of solvent-mediated interactions between hydrophilic and hydrophobic groups, which are commonly called heads and tails. However, the head-tail repulsion is not the only factor affecting the micelle formation. For the first time, we present a systematic study of the effect of chain rigidity on critical micelle concentration and micelle size, which is performed with the dissipative particle dynamics simulation method. Rigidity of the coarse-grained surfactant molecule was controlled by the harmonic bonds set between the second-neighbor beads. Compared to flexible molecules with the nearest-neighbor bonds being the only type of bonded interactions, rigid molecules exhibited a lower critical micelle concentration and formed larger and better-defined micelles. By varying the strength of head-tail repulsion and the chain rigidity, we constructed two-dimensional diagrams presenting how the critical micelle concentration and aggregation number depend on these parameters. We found that the solutions of flexible and rigid molecules that exhibited approximately the same critical micelle concentration could differ substantially in the micelle size and shape depending on the chain rigidity. With the increase of surfactant concentration, primary micelles of more rigid molecules were found less keen to agglomeration and formation of nonspherical aggregates characteristic of flexible molecules.

Three-dimensional hysteresis compensation enhances accuracy of robotic artificial muscles

Science.gov (United States)

Zhang, Jun; Simeonov, Anthony; Yip, Michael C.

2018-03-01

Robotic artificial muscles are compliant and can generate straight contractions. They are increasingly popular as driving mechanisms for robotic systems. However, their strain and tension force often vary simultaneously under varying loads and inputs, resulting in three-dimensional hysteretic relationships. The three-dimensional hysteresis in robotic artificial muscles poses difficulties in estimating how they work and how to make them perform designed motions. This study proposes an approach to driving robotic artificial muscles to generate designed motions and forces by modeling and compensating for their three-dimensional hysteresis. The proposed scheme captures the nonlinearity by embedding two hysteresis models. The effectiveness of the model is confirmed by testing three popular robotic artificial muscles. Inverting the proposed model allows us to compensate for the hysteresis among temperature surrogate, contraction length, and tension force of a shape memory alloy (SMA) actuator. Feedforward control of an SMA-actuated robotic bicep is demonstrated. This study can be generalized to other robotic artificial muscles, thus enabling muscle-powered machines to generate desired motions.

Noninvasive reconstruction of the three-dimensional ventricular activation sequence during pacing and ventricular tachycardia in the rabbit heart.

Science.gov (United States)

Han, Chengzong; Pogwizd, Steven M; Killingsworth, Cheryl R; He, Bin

2011-01-01

Ventricular arrhythmias represent one of leading causes for sudden cardiac death, a significant problem in public health. Noninvasive imaging of cardiac electric activities associated with ventricular arrhythmias plays an important role in better our understanding of the mechanisms and optimizing the treatment options. The present study aims to rigorously validate a novel three-dimensional (3-D) cardiac electrical imaging (3-DCEI) technique with the aid of 3-D intra-cardiac mapping during paced rhythm and ventricular tachycardia (VT) in the rabbit heart. Body surface potentials and intramural bipolar electrical recordings were simultaneously measured in a closed-chest condition in thirteen healthy rabbits. Single-site pacing and dual-site pacing were performed from ventricular walls and septum. VTs and premature ventricular complexes (PVCs) were induced by intravenous norepinephrine (NE). The non-invasively imaged activation sequence correlated well with invasively measured counterparts, with a correlation coefficient of 0.72 and a relative error of 0.30 averaged over all paced beats and NE-induced PVCs and VT beats. The averaged distance from imaged site of initial activation to measured site determined from intra-cardiac mapping was ∼5mm. These promising results suggest that 3-DCEI is feasible to non-invasively localize the origins and image activation sequence of focal ventricular arrhythmias.

Three-dimensional simulation of grain mixing in three different rotating drum designs for solid-state fermentation

NARCIS (Netherlands)

Schutyser, M.A.I.; Weber, F.J.; Briels, W.J.; Boom, R.M.; Rinzema, A.

2002-01-01

A previously published two-dimensional discrete particle simulation model for radial mixing behavior of various slowly rotating drums for solid-state fermentation (SSF) has been extended to a three-dimensional model that also predicts axial mixing. Radial and axial mixing characteristics were

Three-dimensional effects of curved plasma actuators in quiescent air

International Nuclear Information System (INIS)

Wang Chincheng; Durscher, Ryan; Roy, Subrata

2011-01-01

This paper presents results on a new class of curved plasma actuators for the inducement of three-dimensional vortical structures. The nature of the fluid flow inducement on a flat plate, in quiescent conditions, due to four different shapes of dielectric barrier discharge (DBD) plasma actuators is numerically investigated. The three-dimensional plasma kinetic equations are solved using our in-house, finite element based, multiscale ionized gas (MIG) flow code. Numerical results show electron temperature and three dimensional plasma force vectors for four shapes, which include linear, triangular, serpentine, and square actuators. Three-dimensional effects such as pinching and spreading the neighboring fluid are observed for serpentine and square actuators. The mechanisms of vorticity generation for DBD actuators are discussed. Also the influence of geometric wavelength (λ) and amplitude (Λ) of the serpentine and square actuators on vectored thrust inducement is predicted. This results in these actuators producing significantly better flow mixing downstream as compared to the standard linear actuator. Increasing the wavelengths of serpentine and square actuators in the spanwise direction is shown to enhance the pinching effect giving a much higher vertical velocity. On the contrary, changing the amplitude of the curved actuator varies the streamwise velocity significantly influencing the near wall jet. Experimental data for a serpentine actuator are also reported for validation purpose.

Fabrication of three-dimensional carbon microelectrodes for electrochemical sensing

DEFF Research Database (Denmark)

Hemanth, Suhith

Carbon microelectrodes have a wide range of applications because of their unique material properties and biocompatibility. The aim of the research work carried out in this thesis was to develop three-dimensional (3D) carbon microelectrodes for electrochemical applications. Three different fabrica...

Three-Dimensional Gauge Theories and ADE Monopoles

OpenAIRE

Tong, David

1998-01-01

We study three-dimensional N=4 gauge theories with product gauge groups constructed from ADE Dynkin diagrams. One-loop corrections to the metric on the Coulomb branch are shown to coincide with the metric on the moduli space of well-seperated ADE monopoles. We propose that this correspondence is exact.

A three-dimensional model of a gap junction

International Nuclear Information System (INIS)

Xylouris, K.; Wittum, G.

2009-01-01

Gap junctions are effective electric couplings between neurons and form a very important way of communication between them. Since they can be considered as the points on the neuron's membrane on which for example dendrites of different cells become one piece, in three dimensions they can be modelled by observing this property in the created geometry. Thus they can be easily made part in an already existing 3-dimensional model for signal propagation on the neuron's membrane, if the geometries are chosen in such a way respect the blending of the membranes. A small network of two cells was created, which blend in their dendrites and a simulation of the three-dimensional model was carried out which reveals the fast transmission of the signal from one cell to the other.

The thermoelectric performance of bulk three-dimensional graphene

Energy Technology Data Exchange (ETDEWEB)

Yang, Zhi, E-mail: yangzhi@tyut.edu.cn [Key Lab of Advanced Transducers and Intelligent Control System, Ministry of Education and Shanxi Province, Taiyuan University of Technology, Taiyuan 030024 (China); College of Physics and Optoelectronics, Taiyuan University of Technology, Taiyuan 030024 (China); Lan, Guoqiang; Ouyang, Bin [Department of Mining and Materials Engineering, McGill University, Montreal H3A 0C5 (Canada); Xu, Li-Chun; Liu, Ruiping [College of Physics and Optoelectronics, Taiyuan University of Technology, Taiyuan 030024 (China); Liu, Xuguang, E-mail: liuxuguang@tyut.edu.cn [Key Lab of Interface Science and Engineering in Advanced Materials, Ministry of Education, Taiyuan University of Technology, Taiyuan 030024 (China); College of Chemistry and Chemical Engineering, Taiyuan University of Technology, Taiyuan 030024 (China); Song, Jun [Department of Mining and Materials Engineering, McGill University, Montreal H3A 0C5 (Canada)

2016-11-01

The electronic and thermoelectric properties of a new carbon bulk material, three-dimensional (3D) graphene, are investigated in this study. Our results show that 3D graphene has unique electronic structure, i.e., near the Fermi level there exist Dirac cones. More importantly, the thermoelectric performance of 3D graphene is excellent, at room temperature the thermoelectric figure of merit (ZT) is 0.21, an order of magnitude higher than that of graphene. By introducing line defects, the ZT of 3D graphene could be enhanced to 1.52, indicating 3D graphene is a powerful candidate for constructing novel thermoelectric materials. - Highlights: • There exist Dirac cones in three-dimensional (3D) graphene. • The thermoelectric performance of 3D graphene is excellent. • The defective 3D graphene has better thermoelectric performance.

A three-dimensional neutron transport benchmark solution

International Nuclear Information System (INIS)

Ganapol, B.D.; Kornreich, D.E.

1993-01-01

For one-group neutron transport theory in one dimension, several powerful analytical techniques have been developed to solve the neutron transport equation, including Caseology, Wiener-Hopf factorization, and Fourier and Laplace transform methods. In addition, after a Fourier transform in the transverse plane and formulation of a pseudo problem, two-dimensional (2-D) and three-dimensional (3-D) problems can be solved using the techniques specifically developed for the one-dimensional (1-D) case. Numerical evaluation of the resulting expressions requiring an inversion in the transverse plane have been successful for 2-D problems but becomes exceedingly difficult in the 3-D case. In this paper, we show that by using the symmetry along the beam direction, a 2-D problem can be transformed into a 3-D problem in an infinite medium. The numerical solution to the 3-D problem is then demonstrated. Thus, a true 3-D transport benchmark solution can be obtained from a well-established numerical solution to a 2-D problem

Three-dimensional reconstruction used in the diagnosis and treatment of depressed fracture of skull

International Nuclear Information System (INIS)

Li Liang; Luo Zhikun; Lin Xiaohui; Liu Shuyi; Chen Xu; Liu Chenghui

2005-01-01

Objective: To evaluate three-dimensional reconstruction used in the diagnosis and management of depressed fracture of skull. Methods: The images of CT scan and three-dimensional reconstruction in 23 patients with depressed fracture of skull were studied. The clinical treatment was guided by the images. Results: The fracture site and depth in all 23 cases were well demonstrated in the imaging of three-dimensional reconstruction, which successfully guided the clinical management in every case. Conclusion: Three-dimensional reconstruction is a valuable modality for the diagnosis and management of depressed fracture of skull. (authors)

Three dimensional macroporous architectures and aerogels built of carbon nanotubes and/or graphene: synthesis and applications.

Science.gov (United States)

Nardecchia, Stefania; Carriazo, Daniel; Ferrer, M Luisa; Gutiérrez, María C; del Monte, Francisco

2013-01-21

Carbon nanotubes and graphene are some of the most intensively explored carbon allotropes in materials science. This interest mainly resides in their unique properties with electrical conductivities as high as 10(4) S cm(-1), thermal conductivities as high as 5000 W m(-1) K and superior mechanical properties with elastic moduli on the order of 1 TPa for both of them. The possibility to translate the individual properties of these monodimensional (e.g. carbon nanotubes) and bidimensional (e.g. graphene) building units into two-dimensional free-standing thick and thin films has paved the way for using these allotropes in a number of applications (including photocatalysis, electrochemistry, electronics and optoelectronics, among others) as well as for the preparation of biological and chemical sensors. More recently and while recognizing the tremendous interest of these two-dimensional structures, researchers are noticing that the performance of certain devices can experience a significant enhancement by the use of three-dimensional architectures and/or aerogels because of the increase of active material per projected area. This is obviously the case as long as the nanometre-sized building units remain accessible so that the concept of hierarchical three-dimensional organization is critical to guarantee the mass transport and, as consequence, performance enhancement. Thus, this review aims to describe the different synthetic processes used for preparation of these three-dimensional architectures and/or aerogels containing either any or both allotropes, and the different fields of application in which the particular structure of these materials provided a significant enhancement in the efficacy as compared to their two-dimensional analogues or even opened the path to novel applications. The unprecedented compilation of information from both CNT- and graphene-based three-dimensional architectures and/or aerogels in a single revision is also of interest because it allows

Guide to Three Dimensional Structure and Motion Factorization

CERN Document Server

Wang, Guanghui

2011-01-01

The problem of structure and motion recovery from image sequences is an important theme in computer vision. Considerable progress has been made in this field during the past two decades, resulting in successful applications in robot navigation, augmented reality, industrial inspection, medical image analysis, and digital entertainment, among other areas. However, many of these methods work only for rigid objects and static scenes. The study of non-rigid structure from motion is not only of academic significance, but also has important practical applications in real-world, nonrigid or dynamic s

A simple remark on three dimensional gauge theories

International Nuclear Information System (INIS)

Lemes, V.E.R.; Linhares de Jesus, C.; Sasaki, C.A.G.; Sorella, S.P.; Vilar, L.C.Q.; Ventura, O.S.

1997-08-01

Classical three dimensional Yang-Mills is seen to be related to the topological Chern-Simons term through a nonlinear but fully local and covariant gauge field redefinition. A classical recursive cohomological argument is proved. (author)

Discretization model for nonlinear dynamic analysis of three dimensional structures

International Nuclear Information System (INIS)

Hayashi, Y.

1982-12-01

A discretization model for nonlinear dynamic analysis of three dimensional structures is presented. The discretization is achieved through a three dimensional spring-mass system and the dynamic response obtained by direct integration of the equations of motion using central diferences. First the viability of the model is verified through the analysis of homogeneous linear structures and then its performance in the analysis of structures subjected to impulsive or impact loads, taking into account both geometrical and physical nonlinearities is evaluated. (Author) [pt

The effect of base image window level selection on the dimensional measurement accuracy of resultant three-dimensional image displays

International Nuclear Information System (INIS)

Kurmis, A.P.; Hearn, T.C.; Reynolds, K.J.

2003-01-01

Purpose: The aim of this study was to determine the effect of base image window level selection on direct linear measurement of knee structures displayed using new magnetic resonance (MR)-based three-dimensional reconstructed computer imaging techniques. Methods: A prospective comparative study was performed using a series of three-dimensional knee images, generated from conventional MR imaging (MRI) sections. Thirty distinct anatomical structural features were identified within the image series of which repeated measurements were compared at 10 different window grey scale levels. Results: Statistical analysis demonstrated an excellent raw correlation between measurements and suggested no significant difference between measurements made at each of the 10 window level settings (P>0.05). Conclusions: The findings of this study suggest that unlike conventional MR or CT applications, grey scale window level selection at the time of imaging does not significantly affect the visual quality of resultant three-dimensional reconstructed images and hence the accuracy of subsequent direct linear measurement. The diagnostic potential of clinical progression from routine two-dimensional to advanced three-dimensional reconstructed imaging techniques may therefore be less likely to be degraded by inappropriate MR technician image windowing during the capturing of image series

Interface fracture in laminates at three-dimensional corners

Energy Technology Data Exchange (ETDEWEB)

Myhre Jensen, H.; Veluri, B. [Aarhus Univ.. Aarhus School of Engineering, Aarhus (Denmark)

2012-07-01

Interface failure close to corners has been observed in laminated layered structures. A fracture mechanics based approach focused on modelling the shape of such interface cracks and calculating the critical stress for steady-state propagation has been developed. The crack propagation is investigated by estimating the fracture mechanics parameters including the energy release rate and the three-dimensional mode-mixity along the crack front allowing determining the shape of the crack front profiles. A numerical approach is applied for coupling the far field solutions utilizing the capability of the Finite Element Method to the near field solutions at the crack front based on the J-integral. The developed two-dimensional numerical approach for the calculation of fracture mechanical properties has been validated with three-dimensional models for varying crack front shapes. In this study, a quantitative approach was formulated based on the finite element method with iterative adjustment of the crack front to estimate the critical delamination stress as a function of the fracture criterion and corner angles. The implication of the results on the delamination is discussed in terms of crack front profiles and the critical stresses. (Author)

Three-dimensional analysis of antenna sheaths

International Nuclear Information System (INIS)

Myra, J.R.; D'Ippolito, D.A.; Ho, Y.L.

1996-01-01

The present work is motivated by the importance of r.f. sheaths in determining the antenna-plasma interaction and the sensitivity of the sheaths to the complicated three-dimensional structure of modern ion cyclotron range of frequency (ICRF) antennas. To analyze r.f. sheaths on the plasma facing regions of the launcher, we first calculate the contact points of the tokamak magnetic field lines on the surface of the antenna Faraday screen and nearby limiters for realistic three-dimensional magnetic flux surface and antenna geometries. Next, the r.f. voltage that can drive sheaths at the contact points is determined and used to assess the resulting sheath power dissipation, r.f.-driven sputtering, and r.f.-induced convective cells (which produce edge profile modification). The calculations are embodied in a computer code, ANSAT (antenna sheath analysis tool), and sample ANSAT runs are shown to highlight the physics- and geometry-dependent characteristics of the r.f. sheaths and their relationship to the antenna design. One use of ANSAT is therefore as a design tool, to assess the strengths and weaknesses of a given design with respect to critical voltage handling and edge plasma interaction issues. Additionally, examples are presented where ANSAT has been useful in the analysis and interpretation of ICRF experiments (orig.)

Three-dimensional image signals: processing methods

Science.gov (United States)

Schiopu, Paul; Manea, Adrian; Craciun, Anca-Ileana; Craciun, Alexandru

2010-11-01

Over the years extensive studies have been carried out to apply coherent optics methods in real-time processing, communications and transmission image. This is especially true when a large amount of information needs to be processed, e.g., in high-resolution imaging. The recent progress in data-processing networks and communication systems has considerably increased the capacity of information exchange. We describe the results of literature investigation research of processing methods for the signals of the three-dimensional images. All commercially available 3D technologies today are based on stereoscopic viewing. 3D technology was once the exclusive domain of skilled computer-graphics developers with high-end machines and software. The images capture from the advanced 3D digital camera can be displayed onto screen of the 3D digital viewer with/ without special glasses. For this is needed considerable processing power and memory to create and render the complex mix of colors, textures, and virtual lighting and perspective necessary to make figures appear three-dimensional. Also, using a standard digital camera and a technique called phase-shift interferometry we can capture "digital holograms." These are holograms that can be stored on computer and transmitted over conventional networks. We present some research methods to process "digital holograms" for the Internet transmission and results.

Three-dimensional single-mode nonlinear ablative Rayleigh-Taylor instability

International Nuclear Information System (INIS)

Yan, R.; Aluie, H.; Betti, R.; Sanz, J.; Liu, B.; Frank, A.

2016-01-01

The nonlinear evolution of the single-mode ablative Rayleigh-Taylor instability is studied in three dimensions. As the mode wavelength approaches the cutoff of the linear spectrum (short-wavelength modes), it is found that the three-dimensional (3D) terminal bubble velocity greatly exceeds both the two-dimensional (2D) value and the classical 3D bubble velocity. Unlike in 2D, the 3D short-wavelength bubble velocity does not saturate. The growing 3D bubble acceleration is driven by the unbounded accumulation of vorticity inside the bubble. The vorticity is transferred by mass ablation from the Rayleigh-Taylor spikes to the ablated plasma filling the bubble volume

Dose response study of PVA-Fx gel for three dimensional dose distribution

International Nuclear Information System (INIS)

Brindha, S.; Ayyangar, Komanduri M.; Shen, Bin; Saw, Cheng B.

2001-01-01

Modern radiotherapy techniques involve complex field arrangements using conformal and intensity modulated radiation that requires three dimensional treatment planning. The verification of these plans poses even more challenge. In 1984, Gore et al., proposed that ferrous gel dosimeters combined with magnetic resonance imaging (MRI) could be used to measure three dimensional radiation dose distributions. Since then, there has been much interest in the development of gel dosimetry to aid the determination of three dimensional dose distributions during field arrangements. In this work, preparation and study of the MR characteristics of a PVA-Fx gel reported in the literature is presented

[Advances in the research of application of hydrogels in three-dimensional bioprinting].

Science.gov (United States)

Yang, J; Zhao, Y; Li, H H; Zhu, S H

2016-08-20

Hydrogels are three-dimensional networks made of hydrophilic polymer crosslinked through covalent bonds or physical intermolecular attractions, which can contain growth media and growth factors to support cell growth. In bioprinting, hydrogels are used to provide accurate control over cellular microenvironment and to dramatically reduce experimental repetition times, meanwhile we can obtain three-dimensional cell images of high quality. Hydrogels in three-dimensional bioprinting have received a considerable interest due to their structural similarities to the natural extracellular matrix and polyporous frameworks which can support the cellular proliferation and survival. Meanwhile, they are accompanied by many challenges.

Active vibration reduction of rigid rotor by kinematic excitation of bushes of journal bearings

Directory of Open Access Journals (Sweden)

J. Ondrouch

2010-04-01

Full Text Available Possibilities of active lateral vibration reduction of a symmetric, rigid rotor supported by journal bearings are given. They were obtained by computational modelling. Efficiency of the feedback P and PD controllers in the stable revolution interval was examined. The linearized rotor system model was used. The results of the theoretical analysis are assigned for a testing stand where the bearing bush motions are deactivated by piezoelectric actuators connected to the controllers.

Fabrication of three-dimensional micro-nanofiber structures by a novel solution blow spinning device

Directory of Open Access Journals (Sweden)

Feng Liang

2017-02-01

Full Text Available The fabrication of three-dimensional scaffolds has attracted more attention in tissue engineering. The purpose of this study is to explore a new method for the fabrication of three-dimensional micro-nanofiber structures by combining solution blow spinning and rotating collector. In this study, we successfully fabricated fibers with a minimum diameter of 200 nm and a three-dimensional structure with a maximum porosity of 89.9%. At the same time, the influence of various parameters such as the solvent volatility, the shape of the collector, the feed rate of the solution and the applied gas pressure were studied. It is found that solvent volatility has large effect on the formation of the three-dimensional shape of the structure. The shape of the collector affects the porosity and fiber distribution of the three-dimensional structure. The fiber diameter and fiber uniformity can be controlled by adjusting the solution feed rate and the applied gas pressure. It is feasible to fabricate high-quality three-dimensional micro-nanofiber structure by this new method, which has great potential in tissue engineering.

Supersymmetric partition functions and the three-dimensional A-twist

Energy Technology Data Exchange (ETDEWEB)

Closset, Cyril [Theory Department, CERN,CH-1211, Geneva 23 (Switzerland); Kim, Heeyeon [Perimeter Institute for Theoretical Physics,31 Caroline Street North, Waterloo, N2L 2Y5, Ontario (Canada); Willett, Brian [Kavli Institute for Theoretical Physics, University of California,Santa Barbara, CA 93106 (United States)

2017-03-14

We study three-dimensional N=2 supersymmetric gauge theories on M{sub g,p}, an oriented circle bundle of degree p over a closed Riemann surface, Σ{sub g}. We compute the M{sub g,p} supersymmetric partition function and correlation functions of supersymmetric loop operators. This uncovers interesting relations between observables on manifolds of different topologies. In particular, the familiar supersymmetric partition function on the round S{sup 3} can be understood as the expectation value of a so-called “fibering operator” on S{sup 2}×S{sup 1} with a topological twist. More generally, we show that the 3d N=2 supersymmetric partition functions (and supersymmetric Wilson loop correlation functions) on M{sub g,p} are fully determined by the two-dimensional A-twisted topological field theory obtained by compactifying the 3d theory on a circle. We give two complementary derivations of the result. We also discuss applications to F-maximization and to three-dimensional supersymmetric dualities.

The Topology Optimization of Three-dimensional Cooling Fins by the Internal Element Connectivity Parameterization Method

International Nuclear Information System (INIS)

Yoo, Sung Min; Kim, Yoon Young

2007-01-01

This work is concerned with the topology optimization of three-dimensional cooling fins or heat sinks. Motivated by earlier success of the Internal Element Connectivity Method (I-ECP) method in two dimensional problems, the extension of I-ECP to three-dimensional problems is carried out. The main efforts were made to maintain the numerical trouble-free characteristics of I-ECP for full three-dimensional problems; a serious numerical problem appearing in thermal topology optimization is erroneous temperature undershooting. The effectiveness of the present implementation was checked through the design optimization of three-dimensional fins

Three-dimensional organization of micronuclei induced by colchicine in PtK sub 1 cells

Energy Technology Data Exchange (ETDEWEB)

Geraud, G.; Laquerriere, F.; Masson, C.; Arnoult, J.; Labidi, B.; Hernandez-Verdun, D. (Univ. Pierre et Marie Curie, Paris (France))

1989-03-01

In PtK{sub 1} cells micronucleated by colchicine, the authors previously demonstrated that some micronuclei contain a single chromosome. Here, they investigated interphase chromosome organization in micronucleated PtK{sub 1} cells using conventional electron microscopy and three-dimensional computer reconstruction. The distribution of micronuclei was not always polarized, but in some cells they formed a ring. When this occurred, centrioles and Golgi apparatus were located inside the ring. On freeze-fracture replicas, they observed that nuclear pore distinction among the micronuclei was heterogeneous, and on thin sections some micronuclei displayed an incomplete nuclear envelope, with gaps in the double membrane and areas without lamina or condensed chromatin. By autoradiography, they showed that the fibrillar dots were not sites of active transcription. They applied three dimensional reconstruction to one micronucleated cell containing 22 micronuclei whose size indicated that each micronucleus probably contained one chromosome. In this cell they demonstrated that only the smallest micronuclei had an incomplete nuclear envelope. The presence in micronuclei of either nucleoli or fibrillar dots was found to be mutually exclusive. Taken together, these findings indicate that in the diploid nuclei of PtK{sub 1} cells, the three-dimensional organization of the nucleolar domain seems to be directly controlled by the X-chromosome.

Three-dimensional Majorana fermions in chiral superconductors.

Science.gov (United States)

Kozii, Vladyslav; Venderbos, Jörn W F; Fu, Liang

2016-12-01

Using a systematic symmetry and topology analysis, we establish that three-dimensional chiral superconductors with strong spin-orbit coupling and odd-parity pairing generically host low-energy nodal quasiparticles that are spin-nondegenerate and realize Majorana fermions in three dimensions. By examining all types of chiral Cooper pairs with total angular momentum J formed by Bloch electrons with angular momentum j in crystals, we obtain a comprehensive classification of gapless Majorana quasiparticles in terms of energy-momentum relation and location on the Fermi surface. We show that the existence of bulk Majorana fermions in the vicinity of spin-selective point nodes is rooted in the nonunitary nature of chiral pairing in spin-orbit-coupled superconductors. We address experimental signatures of Majorana fermions and find that the nuclear magnetic resonance spin relaxation rate is significantly suppressed for nuclear spins polarized along the nodal direction as a consequence of the spin-selective Majorana nature of nodal quasiparticles. Furthermore, Majorana nodes in the bulk have nontrivial topology and imply the presence of Majorana bound states on the surface, which form arcs in momentum space. We conclude by proposing the heavy fermion superconductor PrOs 4 Sb 12 and related materials as promising candidates for nonunitary chiral superconductors hosting three-dimensional Majorana fermions.

3D-Ising model as a string theory in three-dimensional euclidean space

International Nuclear Information System (INIS)

Sedrakyan, A.

1992-11-01

A three-dimensional string model is analyzed in the strong coupling regime. The contribution of surfaces with different topology to the partition function is essential. A set of corresponding models is discovered. Their critical indices, which depend on two integers (m,n) are calculated analytically. The critical indices of the three-dimensional Ising model should belong to this set. A possible connection with the chain of three dimensional lattice Pott's models is pointed out. (author) 22 refs.; 2 figs

Three-dimensional trajectory tracking for underactuated AUVs with bio-inspired velocity regulation

Directory of Open Access Journals (Sweden)

Jiajia Zhou

2018-05-01

Full Text Available This paper attempts to address the motion parameter skip problem associated with three-dimensional trajectory tracking of an underactuated Autonomous Underwater Vehicle (AUV using backstepping-based control, due to the unsmoothness of tracking trajectory. Through kinematics concepts, a three-dimensional dynamic velocity regulation controller is derived. This controller makes use of the surge and angular velocity errors with bio-inspired models and backstepping techniques. It overcomes the frequently occurring problem of parameter skip at inflection point existing in backstepping tracking control method and increases system robustness. Moreover, the proposed method can effectively avoid the singularity problem in backstepping control of virtual velocity error. The control system is proved to be uniformly ultimately bounded using Lyapunov stability theory. Simulation results illustrate the effectiveness and efficiency of the developed controller, which can realize accurate three-dimensional trajectory tracking for an underactuated AUV with constant external disturbances. Keywords: Dynamic velocity regulation, Bio-inspired model, Backstepping, Underactuated AUV, Three-dimensional trajectory tracking

Second-Order Systems of ODEs Admitting Three-Dimensional Lie Algebras and Integrability

Directory of Open Access Journals (Sweden)

Muhammad Ayub

2013-01-01

the case of k≥3. We discuss the singular invariant representations of canonical forms for systems of two second-order ODEs admitting three-dimensional Lie algebras. Furthermore, we give an integration procedure for canonical forms for systems of two second-order ODEs admitting three-dimensional Lie algebras which comprises of two approaches, namely, division into four types I, II, III, and IV and that of integrability of the invariant representations. We prove that if a system of two second-order ODEs has a three-dimensional solvable Lie algebra, then, its general solution can be obtained from a partially linear, partially coupled or reduced invariantly represented system of equations. A natural extension of this result is provided for a system of two kth-order (k≥3 ODEs. We present illustrative examples of familiar integrable physical systems which admit three-dimensional Lie algebras such as the classical Kepler problem and the generalized Ermakov systems that give rise to closed trajectories.

A Three-Dimensional Statistical Average Skull: Application of Biometric Morphing in Generating Missing Anatomy.

Science.gov (United States)

Teshima, Tara Lynn; Patel, Vaibhav; Mainprize, James G; Edwards, Glenn; Antonyshyn, Oleh M

2015-07-01

The utilization of three-dimensional modeling technology in craniomaxillofacial surgery has grown exponentially during the last decade. Future development, however, is hindered by the lack of a normative three-dimensional anatomic dataset and a statistical mean three-dimensional virtual model. The purpose of this study is to develop and validate a protocol to generate a statistical three-dimensional virtual model based on a normative dataset of adult skulls. Two hundred adult skull CT images were reviewed. The average three-dimensional skull was computed by processing each CT image in the series using thin-plate spline geometric morphometric protocol. Our statistical average three-dimensional skull was validated by reconstructing patient-specific topography in cranial defects. The experiment was repeated 4 times. In each case, computer-generated cranioplasties were compared directly to the original intact skull. The errors describing the difference between the prediction and the original were calculated. A normative database of 33 adult human skulls was collected. Using 21 anthropometric landmark points, a protocol for three-dimensional skull landmarking and data reduction was developed and a statistical average three-dimensional skull was generated. Our results show the root mean square error (RMSE) for restoration of a known defect using the native best match skull, our statistical average skull, and worst match skull was 0.58, 0.74, and 4.4  mm, respectively. The ability to statistically average craniofacial surface topography will be a valuable instrument for deriving missing anatomy in complex craniofacial defects and deficiencies as well as in evaluating morphologic results of surgery.

Three-dimensional triaxial testing of marine sediments

International Nuclear Information System (INIS)

Nelson, J.D.; Thompson, E.G.

1981-01-01

The purpose of this investigation has been to develop testing methods and upgrade equipment for the determination of shear strength of and constitutive relationships for ocean bottom sediments under true three dimensional triaxial states of stress. The research to date has utilized existing 3-D triaxial equipment capable of controlling the three principal stresses independently of each other. Experiments are currently concerned with up-grading the equipment for use with ocean bottom cohesive soils. In addition, stage triaxial tests using conventional laboratory test equipment are being performed

Three-dimensional portable document format: a simple way to present 3-dimensional data in an electronic publication

NARCIS (Netherlands)

Danz, J.C.; Katsaros, C.

2011-01-01

Three-dimensional (3D) models of teeth and soft and hard tissues are tessellated surfaces used for diagnosis, treatment planning, appliance fabrication, outcome evaluation, and research. In scientific publications or communications with colleagues, these 3D data are often reduced to 2-dimensional

A three-dimensional Dirichlet-to-Neumann operator for water waves over topography

Science.gov (United States)

Andrade, D.; Nachbin, A.

2018-06-01

Surface water waves are considered propagating over highly variable non-smooth topographies. For this three dimensional problem a Dirichlet-to-Neumann (DtN) operator is constructed reducing the numerical modeling and evolution to the two dimensional free surface. The corresponding Fourier-type operator is defined through a matrix decomposition. The topographic component of the decomposition requires special care and a Galerkin method is provided accordingly. One dimensional numerical simulations, along the free surface, validate the DtN formulation in the presence of a large amplitude, rapidly varying topography. An alternative, conformal mapping based, method is used for benchmarking. A two dimensional simulation in the presence of a Luneburg lens (a particular submerged mound) illustrates the accurate performance of the three dimensional DtN operator.