Design and Construction of Cervix Phantom for Brachytherapy Dose Assessment Procedure for Clinical Application

2017 ◽  
pp. 106-109
Author(s):  
Justice Avevor ◽  
Issahaku Shirazu ◽  
Samuel Nii Adu Tagoe ◽  
J. H. Amuasi ◽  
J. J. Fletcher
Keyword(s):  
Clinical Application ◽  
Excellent Result ◽  
Dose Assessment ◽  
Internal Diameter ◽  
Cylindrical Shape ◽  
Assessment Procedure ◽  
External Diameter ◽  
Actual Patient ◽  
Average Patient ◽  
Patient Size

An important point to consider in a brachytherapy dosimetry study is the design of an appropriate phantom size in calculations or experimental measurements. Perspex sheets of various size and thickness are used to design the cervix phantom. The aim of the study is to design and construct cervix phantom to mimic the pelvic segment of a standard adult human patients undergoing Brachytherapy. This is to allow assessment of dose to cervix and the surrounding tissues during cervix Brachytherapy. The methodology include; first phantom design where physical dimensions of the phantom were determined from a sampling of 30 patients’ cases to simulate an average patient size. Secondly, construction of phantom with fabricated cylindrical shape, composed of 6 mm Perspex sheets, and the assembly enclosed with the 4 mm Perspex sheet. The result of the constructed phantom had lateral separation of 34 cm, an anterior and posterior separation of 27 cm; with length of 33 cm. The Perspex pieces were glued to each other with Trichloromethane (chloroform) at room temperature. Chloroform dissolves the Perspex (PMMA), and when applied to the surfaces of the Perspex sheets, the surfaces stick together after the chloroform dries up. In forming the surface of the phantom, the 4 mm Perspex sheet was oven heated to a temperature of 140?C to make the sheet malleable. One end of the phantom was made thicker than the other end by gluing another 6 mm Perspex sheet such that the thickness of that particular end of the phantom was 12 mm. A hole of diameter 6.5 cm, which was a little bit posterior to the phantom, was created central to the 12 mm end of the phantom. The opening created was covered by 11 x 11 cm2 and 12 mm Perspex slab which was formed by gluing two 6 mm sheets together. A hole of diameter 5 cm was also made central to the cover created, such that the centre of this hole matches that of the hole on the end of the phantom. A 2.4 cm thick ring with internal diameter of 5 cm and external diameter of 6 cm was fabricated from 2.4 cm Perspex slab, which was formed from gluing four pieces of 6 mm Perspex sheets together. The fabricated ring was mounted on the 11 x 11 cm2 cover created such that the internal walls of the ring and that of the hole in the cover matches. The ring was then glued to the cover using the chloroform. The built phantom simulate actual patient anatomy and produce an excellent result to be use for clinical application.

scholarly journals Challenges in the Forging of Steel-Aluminum Bearing Bushings

Materials ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 803
Author(s):  
Bernd-Arno Behrens ◽  
Johanna Uhe ◽  
Tom Petersen ◽  
Christian Klose ◽  
Susanne E. Thürer ◽  
...  
Keyword(s):  
Intermetallic Layer ◽  
Dissimilar Materials ◽  
Intermetallic Phases ◽  
Internal Diameter ◽  
External Diameter ◽  
Forming Process ◽  
High Deformation ◽  
Eds Analysis ◽  
Steel Aisi ◽  
Metallurgical Bond

The current study introduces a method for manufacturing steel–aluminum bearing bushings by compound forging. To study the process, cylindrical bimetal workpieces consisting of steel AISI 4820 (1.7147, 20MnCr5) in the internal diameter and aluminum 6082 (3.2315, AlSi1MgMn) in the external diameter were used. The forming of compounds consisting of dissimilar materials is challenging due to their different thermophysical and mechanical properties. The specific heating concept discussed in this article was developed in order to achieve sufficient formability for both materials simultaneously. By means of tailored heating, the bimetal workpieces were successfully formed to a bearing bushing geometry using two different strategies with different heating durations. A metallurgical bond without any forging defects, e.g., gaps and cracks, was observed in areas of high deformation. The steel–aluminum interface was subsequently examined by optical microscopy, scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). It was found that the examined forming process, which utilized steel–aluminum workpieces having no metallurgical bond prior to forming, led to the formation of insular intermetallic phases along the joining zone with a maximum thickness of approximately 5–7 µm. The results of the EDS analysis indicated a prevailing FexAly phase in the resulting intermetallic layer.

scholarly journals Instruments and Methods High Pressure Coupling for Pipe in Deep Water Filled Bore Holes

1963 ◽  
Vol 4 (36) ◽  
pp. 809-812
Author(s):  
R. L. Shreve
Keyword(s):  
High Pressure ◽  
Water Pressure ◽  
The Other ◽  
Internal Diameter ◽  
External Diameter ◽  
Synthetic Rubber ◽  
External Water Pressure ◽  
External Water ◽  
One Year ◽  
Aluminum Pipe

AbstractIn August 1961 an aluminum pipe (3.5 cm. internal diameter, 4.2 cm. external diameter) having 92 specially modified socket couplings (5.0 cm. external diameter) sealed with a quick-polymerizing synthetic rubber was sunk 226 m. in a vertical water-filled bore hole in Blue Glacier, Washington. U.S.A. The geometry of threads and mating surfaces of pipe and coupling was designed to cause increasing external water pressure to tighten the seal. One joint at a depth of 66 m. immediately developed an extremely slow leak (probably because of faulty cleaning), but the other 91 joints apparently were sound, as the pipe was free of water to a depth of at least 157 m. when resurveyed after one year.

INTERCOMPARISON ON INTERNAL DOSE ASSESSMENT FOR NUCLEAR POWER PLANTS IN KOREA

2019 ◽  
Vol 186 (4) ◽  
pp. 524-529
Author(s):  
Si Young Kim
Keyword(s):  
Nuclear Power ◽  
Power Plants ◽  
Nuclear Power Plants ◽  
Evaluation Method ◽  
Dose Assessment ◽  
Assessment Procedure ◽  
Internal Dose ◽  
Nuclear Facilities ◽  
International Intercomparison ◽  
Selection Of

Abstract The intercomparison test is a quality assurance activity performed for internal dose assessment. In Korea, the intercomparison test on internal dose assessment was carried out for nuclear facilities in May 2018. The test involved four nuclear facilities in Korea, and seven exposure scenarios were applied. These scenarios cover the intake of 131I, a uranium mixture, 60Co and tritium under various conditions. This paper only reviews the participant results of three scenarios pertinent to the operation of nuclear power plants and adopts the statistical evaluation method, used in international intercomparison tests, to determine the significance values of the results. Although no outliers were established in the test, improvements in the internal dose assessment procedure were derived. These included the selection of intake time, selection of lung absorption type according to the chemical form and consideration of the contribution of previous intake.

scholarly journals XIX.—Preliminary Note on the Compressibility of Glass

1880 ◽  
Vol 29 (2) ◽  
pp. 589-598
Author(s):  
J. Y. Buchanan
Keyword(s):  
Pressure Gauge ◽  
Steel Tube ◽  
Internal Diameter ◽  
Hydraulic Pressure ◽  
External Diameter ◽  
Preliminary Note ◽  
Actual Observation ◽  
Peculiar Form ◽  
Glass Tubes ◽  
The One

The following experiments were undertaken with a view to determine by actual observation the effect produced on solids by hydraulic pressure.The instrument was constructed according to my directions by Mr Milne of Milton House, about two years ago, but it is only now that I have been able to devote myself to its application to the purposes for which it was designed. It consists of a hydraulic pump, which communicates with a steel receiver capable of holding instruments of considerable size, and also with a second receiver of peculiar form. This receiver consists essentially of a steel tube, terminated at each end by thick glass tubes fitted tightly. It is tapped at the centre with two holes, the one to establish connection with the pump, and the other to admit a pressure gauge or manometer. The steel tube may be of any length, being limited only by the extent of laboratory accommodation at disposal. The tube which I am using at present has a length of a little over six feet, and an internal diameter of about three-tenths of an inch. The solid to be experimented on must be in the form of a rod or wire, and must, at the ends at least, be sufficiently small to be able to enter the terminal glass tubes, which have a bore of 0·08″ and an external diameter of 0·42″. The length of the solid is such that when it rests in the steel tube its ends are visible in the glass terminations.

scholarly journals 4. On the Compressibility of Glass

1880 ◽  
Vol 10 ◽  
pp. 697-698 ◽  
Author(s):  
J. Y. Buchanan
Keyword(s):  
Pressure Gauge ◽  
Steel Tube ◽  
Internal Diameter ◽  
Hydraulic Pressure ◽  
External Diameter ◽  
Hydraulic Pump ◽  
Actual Observation ◽  
Peculiar Form ◽  
Glass Tubes ◽  
The One

AbstractThe experiments related in this paper were undertaken with a view to determine, by actual observation, the effect produced on solids by hydraulic pressure. The instrument used consists of a hydraulic pump, which communicates with a steel receiver capable of holding instruments of considerable size, and also with a second receiver of peculiar form. This receiver consists essentially of a steel tube terminated at each end by thick glass tubes fitted tightly. It is tapped at the centre with two holes, the one to establish connection with the pump and the other to admit a pressure-gauge or manometer. The steel tube may be of any length, being limited only by the extent of laboratory accommodation at disposal. The tube which I am using at present has a length of a little over six feet and an internal diameter of about three-tenths of an inch. The solid to be experimented on must be in the form of rod or wire, and must, at the ends, at least, be sufficiently small to be able to enter the terminal glass tubes, which have a bore of 0·08 inch, and an external diameter of 0·42 inch. The length of the rod or wire is such that, when it rests in the steel tube, its ends are visible in the glass terminations.

Mechanics of large and small cerebral arteries in chronic hypertension

1994 ◽  
Vol 266 (3) ◽  
pp. H1027-H1033 ◽  
Author(s):  
M. A. Hajdu ◽  
G. L. Baumbach
Keyword(s):  
Cerebral Artery ◽  
Posterior Cerebral Artery ◽  
Cerebral Arteries ◽  
Internal Diameter ◽  
Chronic Hypertension ◽  
External Diameter ◽  
Cross Sectional ◽  
Spontaneously Hypertensive ◽  
Wistar Kyoto

The goal of this study was to investigate factors that contribute to reductions in internal diameter of large and small cerebral arteries during chronic hypertension. We measured diameter of second- and third-order branches of the posterior cerebral artery in vitro during maximal dilation with EDTA in 6-mo-old stroke-prone spontaneously hypertensive rats (SHRSP, n = 7) and Wistar-Kyoto rats (WKY, n = 7). Cross-sectional area of the vessel wall, measured histologically, was not significantly different at 70 mmHg in SHRSP and WKY in large or small branches of posterior cerebral artery. In large branches of posterior cerebral artery, external and internal diameters were significantly less at 70 mmHg in SHRSP than in WKY, whereas external and internal diameters converged at 0 mmHg in the two groups of rats. In small branches, on the other hand, external and internal diameters were significantly less at all levels of intravascular pressure in SHRSP than in WKY. The stress-strain relation in posterior cerebral artery of SHRSP was shifted to the left in large branches and to the right in small branches, which indicates that distensibility was reduced in large cerebral arteries of SHRSP and increased in small cerebral arteries. These findings suggest that different mechanisms are responsible for impairment of maximal dilator capacity in large and small cerebral arteries of SHRSP: reduced distensibility in large arteries and remodeling with reduced external diameter in small arteries. Furthermore the findings provide additional support for the concept that hypertrophy may not be a primary factor in impaired maximal dilation.

scholarly journals IV. On the development of electric currents by magnetism and heat

1869 ◽  
Vol 17 ◽  
pp. 265-267
Keyword(s):  
Copper Wire ◽  
Glass Tube ◽  
Rubber Band ◽  
The Other ◽  
Internal Diameter ◽  
External Diameter ◽  
Thin Glass ◽  
Iron Wire ◽  
It Flexibility ◽  
Electric Current Passing

I have devised the following apparatus for demonstrating a relation of current electricity to magnetism and heat. A A, fig. 3, is a wooden base, upon which is supported, by four brass clamps, two, B, B, on each side, a coil of wire, C; the coil is 6 inches long, 1½ inch external diameter, and ⅜ of an inch internal diameter, lined with a thin glass tube; it consists of 18 layers, or about 3000 turns of insulated copper wire of 0·415 millim. diameter (or size No. 26 of ordinary wire-gauge); D is a permanent bar-magnet held in its place by the screws E, E, and having upon its poles two flat armatures of soft iron, F, F, placed edgewise. Within the axis of the coil is a straight wire of soft iron, G, one end of which is held fast by the pillar-screw H, and the other by the cylindrical binding-screw I; the latter screw has a hook, to which is attached a vulcanized india-rubber band, J, which is stretched and held secure by the hooked brass rod K and the pillar-screw L. The screw H is surmounted by a small mercury cup for making connexions with one pole of a voltaic battery, the other pole of the battery being secured to the pillar-screw M, which is also surmounted by a small mercury cup, and is connected with the cylindrical binding-screw I by a copper wire with a middle flattened portion O to impart to it flexibility. The two ends of the fine wire coil are soldered to two small binding-screws at the back; those screws are but partly shown in the sketch, and are for the purpose of connexion with a suitable galvanometer. The armatures F, F are grooved on their upper edges, and the iron wire lies in these grooves in contact with them; and to prevent the electric current passing through the magnet, a small piece of paper or other thin non-conductor is inserted between the magnet and one of the armatures. The battery employed consisted of six Grove’s elements (arranged in one series), with the immersed portion of platinum plates about 5 inches by 3 inches; it was sufficiently strong to heat an iron wire 1·03 millim. diameter and 20·5 centims. long to a low red heat.

Nanocrystallization of Fe-Based Amorphous Alloys Fe73.5Cu1Nb3Si13.5B9 by Yb-Doped Fiber Laser Overlapping Irradiation

2012 ◽  
Vol 482-484 ◽  
pp. 2365-2370 ◽  
Author(s):  
Qian Li Ma ◽  
Yong Bao ◽  
Guo Rui Zhang ◽  
Li Meng Yu ◽  
Ling Fei Ji ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Fiber Laser ◽  
Laser Irradiation ◽  
Soft Magnetic Property ◽  
Internal Diameter ◽  
Soft Magnetic Properties ◽  
External Diameter ◽  
X Ray Diffraction ◽  
Soft Magnetic ◽  
Transmission Electron

The paper presents a laser irradiation method for rapidly fabricating Fe-based nanocrystalline alloys using Yb-doped fiber laser with a wavelength of 1070nm by overlapping irradiation of the heated areas. The samples are annular cores rolled with 20μm-thick and 3.2mm-wide belts of amorphous alloy Fe73.5Cu1Nb3Si13.5B9, which have internal diameter of 14 mm and external diameter of 20 mm. Every side of the samples is irradiated for 15 min by fiber laser. X-ray diffraction and transmission electron microscopy (TEM) are used for microstructure analysis and observation. The samples irradiated by a defocus beam with a diameter of 7.1mm through a lens have better soft magnetic properties than directly by an original collimating beam with a diameter of 6.7mm. The dimension of homogeneous ultrafine grains is about 10nm with a bcc α-Fe (Si), which is the foundation of the excellent soft magnetic property. Uniform laser irradiation and the appropriate laser power are necessary for optimum microstructure and soft magnetic properties.

All-Purpose Packing Cups for Hyper Compressor

2016 ◽  
Author(s):  
Carmelo Maggi ◽  
Jan Wojnar ◽  
Leonardo Tognarelli
Keyword(s):  
Spare Parts ◽  
Internal Diameter ◽  
External Diameter ◽  
Safety Margins ◽  
Two Stages ◽  
Packing Assembly ◽  
Cup Design ◽  
Unique Part ◽  
Sealing Elements ◽  
Compressor Packing

Hyper compressors are designed for LDPE production, compressing ethylene up to 3500bar with only two stages of compression, in order to reach conditions for the polymerization. The high operating and fluctuating pressure strongly impact design and life of all cylinder components. The packing cups are among the most stressed components of a hyper compressor cylinder. They are particularly subjected to very high pulsating pressures, thus fatigue and wear. Therefore, they are periodically replaced during maintenance and are critical for availability of the hyper compressor. A typical hyper compressor packing assembly contains 5 to 6 disc shaped packing cups that contain the plunger sealing rings at the internal diameter. The packing cups are provided with lube oil ducts to lubricate the sealing elements. Typically these ducts extend axially through the assembly to the injection points. For that purpose each packing cup could have a different number of lube oil passages. Moreover, at the external diameter are located passages for packing cooling oil. For these reasons each of the packing cups is a unique part with different machining features. In order to optimize the availability of spare parts and standardize the product, a new design of hyper compressor packing cups has been evaluated, called further “all-purpose packing cup”. The idea was to make the packing cups all equal to each other, and potentially to reduce manufacturing and warehousing costs. This idea has been realized by introducing in a single all-purpose cup, multiple sectors angularly offset with each other. Each sector contains the oil ducts required for a given cup position in the assembly. By rotating the cup about the plunger axis by e.g. 90° or 180° the desired sector can be activated (put in fluid communication with adjacent lube oil ducts). In this way the “all-purpose packing cup” can be mounted in each of the 5 to 6 different positions in the packing assembly. The all-purpose cup design has been analyzed by a well validated FEA approach on the high cycle fatigue and flaw propagation safety margins. The analysis was performed considering all multiple possible load combinations where, depending on the assembly configuration, different active lube oil holes (holes that deliver oil to the plunger) were pressurized while all remaining ducts were left unpressurized.

Optimization Design of CTP Imaging Drum Based on ANSYS

2011 ◽  
Vol 217-218 ◽  
pp. 1781-1788 ◽  
Author(s):  
Jie Fang Xing ◽  
Xiao Yu Ni ◽  
Jie Zhang ◽  
Du Juan Chen
Keyword(s):  
Finite Element ◽  
Optimization Model ◽  
Optimization Design ◽  
Geometric Model ◽  
Element Model ◽  
Internal Diameter ◽  
External Diameter ◽  
Factors Affecting ◽  
Maximum Deformation ◽  
Design Variables

In the imaging process, the deformation of the plate caused by the structure of the drum, finally affecting the quality of the plate, we analyze and optimize the structure of the drum using the finite element method. Selecting the larger three factors affecting the plate deformation as the design variables, and taking minimizing the maximum deformation of the plate as the objective function, we establish the optimization model of the structure of the drum. We use the APDL parametrization language to create the geometric model and finite element model of the drum, and select the contact element to simulate the relationship between the plate and the surface of the drum, and use ANSYS software to optimize the optimization model. It is shown form the result that: the minimum of the maximum deformation of the drum getting from the 8th iteration is 0.0021535mm, significantly reduced compared with the initial value 0.002864mm. At this point, the internal diameter D2 of the drum is 300.04mm, the groove width L2 is 14.323mm, the external diameter of groove height D3 is 338.44mm. It indicates that that the smaller the internal diameter of the drum and the narrower the guide groove on the drum surface are, the smaller the maximum deformation of the plate is, and the guide groove height has little influence on the deformation. The results can be provided as theoretical reference for the design of CTP imaging drum, which has popularization and application value.

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