Cone Research Articles

Model test and numerical simulation on the bearing mechanism of tunnel-type anchorage

The bearing mechanism of tunnel-type anchorage (TTA) for suspension bridges is studied. Model tests are conducted using different shapes of plug bodies, which are circular column shape and circular truncated cone shape. The results show that the plug body of the latter shape possesses much larger bearing capacity, namely 4.48 times at elastic deformation stage and 4.54 times at failure stage compared to the former shape. Numerical simulation is then conducted to understand the mechanical and structural responses of plug body and surrounding rock mass. The mechanical parameters of the surrounding rock mass are firstly back-analyzed based on the monitoring data. The calculation laws of deformation and equivalent plastic strain show that the numerical simulation results are rational and provide subsequent mechanism analysis with an established basis. Afterwards, the bearing mechanism of TTA is studied. It is concluded that the plug body of circular truncated cone shape is able to take advantage of the material strength of the surrounding rock mass, which greatly enhances its bearing capacity. The ultimate bearing capacity of TTA, therefore, is concluded to be determined by the material strength of surrounding rock mass. Finally, recommendations for TTA design are proposed and discussed.

Some Fixed Point Theorems on c-distance

In this paper, we prove fixed point theorems on c-distance in ordered cone metric spaces. Our results are generalize, improve and extension of the recent work existing in the literature.

Coupling between a glacier and a soft bed: II Model results

The relation between the local effective pressure and shear stress on till beneath Storglaciaren, Sweden, discussed in Iverson and others (1999), provides an empirical basis for studying the processes that control the strength of the ice/bed coupling. Particles in the bed that protrude into the glacier sole support shear stresses that are limited by either ploughing or the traditional sliding mechanisms. Model calculations, based on studies of cone penetration through fine-grained sediment and sliding theory, agree with the observed relation between shear stress and effective pressure if the water layer at the ice/bed interface is assumed to thicken rapidly as the effective pressure approaches zero. Studies of the hydraulics of linked cavities provide support for this assumption, if the mean thickness of the water layer reflects the extent of microcavity development at the interface. Comparison of the calculated shear stress with the ultimate strength of till suggests that bed deformation limits the shear stress on till beneath Storglaciaren only at intermediate effective pressures; at very low effective pressures, like those inferred at the site of the tiltmeter discussed in Iverson and others (1999), and at sufficiently high effective pressures, ploughing and sliding should focus motion near the glacier sole. A calculation using parameter values appropriate for Ice Stream B, West Antarctica, suggests that ploughing may occur there at shear stresses not sufficient to deform the bed at depth. This conclusion is reinforced by the likelihood that pore pressures in excess of hydrostatic should develop down-glacier from ploughing particles, thereby weakening the bed near the glacier sole. However, given the apparent sensitivity of the ice/bed coupling to basal conditions that may be highly variable, any blanket assumption regarding the flow mechanism of ice masses on soft beds should probably be viewed with skepticism.

Methods of Mathematical Modeling of the Action of a Medium on a Conical Body

We consider a mathematical model of a plane-parallel action of a medium on a rigid body whose surface has a part which is a circular cone. We present a complete system of equations of motion under the quasi-stationarity conditions. The dynamical part of equations of motion form an independent system that possesses an independent second-order subsystem on a two-dimensional cylinder. We obtain an infinite family of phase portraits on the phase cylinder of quasi-velocities corresponding to the presence in the system of only a nonconservative pair of forces.

Healing of transverse root fracture evaluated by using cone beam computed tomography: Case report with 2 years follow-up

A human dental trauma usually occurs in young patients involving an anterior dentition. A horizontal root fracture (HRF) is uncommon, being only 0.5–7.0% of all traumatic dental injuries. A 9-year-old Saudi boy was received trauma on his face causing HRF at both right (#11) and left (#21) maxillary central incisors. The apical third of tooth #11 was fractured, and #21 was lost. Clinical and radiographic examinations investigation were done, and proper management was carried out. The patient was asymptomatic at 2 years follow-up, and the cone beam computed tomography shows good healing of the two fragments that could be done with fibrous tissue.

A reappraisal of the Italian record of the Cretaceous pachycormid fish Protosphyraena Leidy, 1857

The genus Protosphyraena is known mainly from partial remains, consisting of isolated blade-like teeth, conical rostra and scythe-like pectoral fins. This paper provides a new insight into partial specimens of the genus Protosphyraena from the Cretaceous of NE Italy, housed in historical collections from local paleontological museums and previously poorly known to the international scientific community. The specimens are referred to the species Protosphyraena ferox, based on the morphology of the pectoral fin. This attribution is consistent with the paleobiogeographic distribution and stratigraphic range of this taxon. The Italian material provides new information about the distribution in time and space of Protosphyraena, which is relatively poorly known despite being an iconic taxon. The Italian remains, although fragmentary, contribute to fill a gap in the central Tethys record of the genus, whose range probably extended worldwide, considering also the genus Australopachycormus and its profound (possibly congeneric) similarities.

Static Limit Analysis of Reinforced Soil Structures by a Simple Finite Element and Second-Order Cone Programming

TO DISCRETIZE REINFORCED SOIL STRUCTURES IN PLANE STRAIN AND PREDICT LOWER BOUNDS ON THEIR COLLAPSE LOAD, A SIMPLE THREE-NODE TRIANGULAR FINITE ELEMENT IS FORMULATED. THE ELEMENT SATISFIES THE EQUILIBRIUM EQUATIONS AND THE MECHANICAL BOUNDARY CONDITIONS IN A WEAK SENSE. A MODIFIED MOHR-COULOMB YIELD SURFACE IS ADOPTED TO DESCRIBE THE REINFORCED SOIL BEHAVIOR FROM A MACROMECHANICS POINT OF VIEW. IT IS ALSO TAKEN INTO ACCOUNT THE POSSIBILITY OF TENSION FAILURE OF THE REINFORCEMENT AND FAILURE OF THE REINFORCEMENT INTERFACE. THE STATED NONLINEAR CONVEX OPTIMIZATION PROBLEM IS CAST AS SECOND-ORDER CONE PROGRAMMING. NUMERICAL EXAMPLES ILLUSTRATE THE PREDICTIVE ACCURACY OF THE ABOVE SCHEME AS WELL AS THE EFFICIENCY AND SPEED OF AN INTERIOR-POINT METHOD TO REACH OPTIMAL SOLUTIONS.

Analysis of Bearing Capacity Improvement Effect of Inner Cone Penetration Equiped Open-Ended Steel Pipe Pile

Analysis of Bearing Capacity Improvement Effect of Inner Cone Penetration Equiped Open-Ended Steel Pipe Pile

Use of cone beam computed tomography, was it necessary?

Use of cone beam computed tomography, was it necessary?

Development of a New Water Moving Device Using Rotating Cones

Development of a New Water Moving Device Using Rotating Cones

Study on Multi-phase Flow Characteristics in a Conical Spouted Bed Fast Pyrolysis Reactor using Electrical Capacitance Volume Tomography

Study on Multi-phase Flow Characteristics in a Conical Spouted Bed Fast Pyrolysis Reactor using Electrical Capacitance Volume Tomography

TLQP peptides in Amyotrophic Lateral Sclerosis

TLQP peptides (TLQPp) act on synaptic strengthening or against neuronal apoptosis but their involvement in Amyotrophic Lateral Sclerosis (ALS) is not well known. We used an ALS animal model (SOD1-G93A) and human tissues (plasma and fibroblasts from both patients and controls), to address the TLQPp expression and their modulation in ALS mechanisms. Mouse motor neuronal cells (NSC-34), were used to study the neuroprotective role of the TLQP-21 against oxidative stress induced by Sodium Arsenite. TLQPp were immunoquantified by ELISA, their cell expression studied by immunofluorescence while cell viability was addressed by MTT assay. In the NSC-34 naive cells, TLQPp were found within the cytoplasm, axons and growth cones. Upon stress, they appeared immunolocalized exclusively within a cytoplasmatic area, close to the nucleus, (probably the Golgi). Moreover, under stress, TLQPp levels were reduced (42%, p=3.1x10-6), while the exogenous increase of TLQP-21 improved cell viability (13%, p= 0.018). In naive fibroblasts, TLQPp were also similarly localized in an area, likely the Golgi, of patients and controls while their reduction (31%, p=0.03) was observed in cells with TARDBP-A382T mutation. Stress granules only appeared after SA treatment, and did not contain TLQPp. In plasma, a reduced release of TLQPp was associated with the beginning of the clinical motor symptoms in patients (12%, p=0.026), and with a pre-symptomatic stage in mutant mice (26.3%, p=0.048). Finally, in mouse spinal cord we identified by vescicular acetylcholine transporter (VAChT) antibody, a specific localization of the TLQPp in the motor neurons with a reduction in the pre-symptomatic stage of mutant mice. In conclusion, TLQPp are reduced in the stressed NSC-34 cells, mutant mouse motor neurons as well as in fibroblasts with TARDBP-A382T mutation that also induces production of reactive oxygen specie. Hence, we suggest that their reduction may occur in response to oxidative stress. They could be also considered as early biomarkers, while TLQP-21 acts as neuroprotective factor.

Clinical Applications of Genome Anthropology

Evolution is the only weapon that every living species has to survive to the changes of the surrounding environment. The clinical applications of genome anthropological studies has been studied. The goal is to understand with a global approach how certain body districts have changed during the evolution and how these changes have affected the contemporary man. All these researches investigated populations lived thousands of years ago and Tanaka craniofacial and cervical spine fresh cadaver dissective technic has enabled the creation of a comprehensive diagnostic protocol [1]. One of the most important tool of this diagnostic protocol is the use of all-skull CT cone beam which shows the anatomical structures in a real 3D perspective using a specific software. The use of this test has become a standard because the radiation dose administered is lower than the usual radiographs performed for the orthodontic diagnosis [2]. Among the innovative aspects of this protocol there is the evaluation of anatomical structures by means of cone-beam CT which allow us to create a specific therapy for each patient paying attention to gnathological and postural disorders. Patients are evaluated and monitored during the therapy using a clinical record which include a VAS test. VAS is a validated test and is used by patients to determine the effectiveness of the chosen therapy.

Paper cone

paper cone

Расчет поля равномерно поляризованных и равномерно намагниченных многогранников

In describing electrical phenomena in material areas (crystals and domains in ferroelectrics and ferromagnetics), the latter can be regarded to be uniformly charged over their volumes, uniformly polarized, and uniformly magnetized. The material areas may have arbitrary shapes, but in a first approximation they can be considered to be polyhedral. The problem of determining the field of uniformly polarized and uniformly magnetized polyhedrons, and the field of a uniformly charged polyhedral body is considered. Expressions for the field and potential of a uniformly charged infinitesimally thin polygonal plate are obtained, which contain only elementary functions. The following plate shapes are considered: trapezoid, rectangle, and rectangular and oblique triangles. Features pertinent to the field of arbitrarily shaped uniformly polarized and uniformly magnetized bodies are described. The following uniformly polarized and uniformly magnetized bodies are considered: a right-angle prism, a polyhedron with the symmetry axis of the third and higher orders, an infinitely long trapezoid body, and a truncated right circular cone.

Super-AGB Stars and their Role as Electron Capture Supernova Progenitors

AbstractWe review the lives, deaths and nucleosynthetic signatures of intermediate-mass stars in the range ≈6–12 M⊙, which form super-AGB stars near the end of their lives. The critical mass boundaries both between different types of massive white dwarfs (CO, CO–Ne, ONe), and between white dwarfs and supernovae, are examined along with the relative fraction of super-AGB stars that end life either as an ONe white dwarf or as a neutron star (or an ONeFe white dwarf), after undergoing an electron capture supernova event. The contribution of the other potential single-star channel to electron-capture supernovae, that of the failed massive stars, is also discussed. The factors that influence these different final fates and mass limits, such as composition, rotation, the efficiency of convection, the nuclear reaction rates, mass-loss rates, and third dredge-up efficiency, are described. We stress the importance of the binary evolution channels for producing electron-capture supernovae. Recent nucleosynthesis calculations and elemental yield results are discussed and a new set of s-process heavy element yields is presented. The contribution of super-AGB star nucleosynthesis is assessed within a Galactic perspective, and the (super-)AGB scenario is considered in the context of the multiple stellar populations seen in globular clusters. A brief summary of recent works on dust production is included. Last, we conclude with a discussion of the observational constraints and potential future advances for study into these stars on the low mass/high mass star boundary.

The Radon Transform over Cones with Vertices on the Sphere and Orthogonal Axes

Recovering a function from its integrals over circular cones recently gained significance because of its relevance to novel medical imaging technologies such as emission tomography using Compton cameras. In this paper, we investigate the case where the vertices of the cones of integration are restricted to a sphere in $n$-dimensional space and where the symmetry axes are orthogonal to the sphere. We show invertibility of the considered transform and develop an inversion method based on series expansion and reduction to a system of one-dimensional integral equations of generalized Abel type. Since the arising kernels do not satisfy standard assumptions, we also develop a uniqueness result for generalized Abel integral equations where the kernel has zeros on the diagonal. Finally, we demonstrate how to efficiently implement our inversion method and present numerical results.

The Jordan algebraic structure of the circular cone

The Jordan algebraic structure of the circular cone

Truncated Circular Cone Slot Antenna Array That Radiates a Circularly Polarized Conical Beam

A truncated circular cone slot array antenna that radiates a circularly polarized (CP) conical beam is presented. The direction into which the conical beam radiates depends mainly on the tilt angle of the outer conductor as well as the proper arrangement of the positions of its two slot arrays. The CP property is realized by introducing quasi-perpendicular slots that are cut into the outer conductor of a truncated circular cone. To illustrate the performance characteristics of this CP conical beam antenna, the tilt angle is set to 45° and the beam angle is pointed at 45° from boresight within the operating band. A prototype was fabricated and tested. The measured results demonstrate that its −10 dB impedance bandwidth ( $\vert S_{{11}}{\rm{\vert \, dB) is 720 MHz, from 5.05 to 5.77 GHz; and its 3 dB axial-ratio (AR) bandwidth is 500 MHz, from 5.5 to 6.0 GHz. Its realized gain over this AR bandwidth ranges from 4.84 to 5.8 dB. The designed beam direction can be easily changed to meet specific application requirements. Moreover, it can be readily reconfigured to be a conformal antenna mounted on the top of a high-speed mobile platform.

What should we know about photon dose calculation algorithms used for radiotherapy? Their impact on dose distribution and medical decisions based on TCP/NTCP

The dose calculation algorithms, integrated in a radiotherapy treatment planning system, use different approximations to swiftly compute the dose distributions. Any biological effect is somehow related to the dose delivered to the tissues. Thus, the optimization of treatment planning in radiation oncology requires, as a basis, the most accurate dose calculation to carry out the best possible prediction of the Normal Tissue Complication Probability (NTCP), as well as Tumor Control Probability (TCP). Presently, a number of bio-mathematical models exist to estimate TCP and NTCP from a physical calculated dose using the differential dose volume histogram (dDVH). The purpose of this review is to highlight the link between any change of algorithms and possible significant changes of DVH metrics, TCP, NTCP and even more of estimated Quality-adjusted life years (QALY) based on predicted NTCP. The former algorithms, such as pencil beam convolution (PBC) algorithm with 1D or 3D density correction methods, overestimated the TCP while underestimating NTCP for lung cancer. The magnitude of error depends on the algorithms, the radiobiological models and their assumed radiobiological parameters setting. The over/under estimation of radiotherapy outcomes can reach up to 50% relatively. Presently, the anisotropic analytical algorithm (AAA), collapsed cone convolution algorithm (CCC), Acuros-XB or Monte Carlo are the most recommended algorithms to consistently estimate the TCP/ NTCP outcomes and QALY score, to rank and compare radiotherapy plans, to make a useful medical decision regarding the best plan. This paper points out also that the values of the NTCP radiobiological parameters should be adjusted to each dose calculation algorithm to provide the most accurate estimates.