Aircraft interior noise models - Sidewall trim, stiffened structures, and cabin acoustics with floor partition

Science.gov (United States)

Pope, L. D.; Wilby, E. G.; Willis, C. M.; Mayes, W. H.

1983-01-01

As part of the continuing development of an aircraft interior noise prediction model, in which a discrete modal representation and power flow analysis are used, theoretical results are considered for inclusion of sidewall trim, stiffened structures, and cabin acoustics with floor partition. For validation purposes, predictions of the noise reductions for three test articles (a bare ring-stringer stiffened cylinder, an unstiffened cylinder with floor and insulation, and a ring-stringer stiffened cylinder with floor and sidewall trim) are compared with measurements.

Stress and reliability analyses of multilayered composite cylinder under thermal and mechanical loads

Science.gov (United States)

Wang, Xiaohua

The coupling resulting from the mutual influence of material thermal and mechanical parameters is examined in the thermal stress analysis of a multilayered isotropic composite cylinder subjected to sudden axisymmetric external and internal temperature. The method of complex frequency response functions together with the Fourier transform technique is utilized. Because the coupling parameters for some composite materials, such as carbon-carbon, are very small, the effect of coupling is neglected in the orthotropic thermal stress analysis. The stress distributions in multilayered orthotropic cylinders subjected to sudden axisymmetric temperature loading combined with dynamic pressure as well as asymmetric temperature loading are also obtained. The method of Fourier series together with the Laplace transform is utilized in solving the heat conduction equation and thermal stress analysis. For brittle materials, like carbon-carbon composites, the strength variability is represented by two or three parameter Weibull distributions. The 'weakest link' principle which takes into account both the carbon-carbon composite cylinders. The complex frequency response analysis is performed on a multilayered orthotropic cylinder under asymmetrical thermal load. Both deterministic and random thermal stress and reliability analyses can be based on the results of this frequency response analysis. The stress and displacement distributions and reliability of rocket motors under static or dynamic line loads are analyzed by an elasticity approach. Rocket motors are modeled as long hollow multilayered cylinders with an air core, a thick isotropic propellant inner layer and a thin orthotropic kevlar-epoxy case. The case is treated as a single orthotropic layer or a ten layered orthotropic structure. Five material properties and the load are treated as random variable with normal distributions when the reliability of the rocket motor is analyzed by the first-order, second-moment method (FOSM).

An experimental investigation of composite floor vibration due to human activities. A case study

Directory of Open Access Journals (Sweden)

Yasser G. Mohamed Fahmy

2012-12-01

Full Text Available Composite steel floor decks are used in a large variety of constructions with long spans, such as administration and commercial buildings, hotels and bridges. Due to decreased floor mass and longer span lengths, floor vibrations have become an area of concern. Floor decks with low frequencies may be in resonance with the vibrations due to human activities and the resulting acceleration may exceed human comfort levels. The design of slender floor structures, with steel or composite cross sections, is often limited by the serviceability criteria such as deflection limits and vibration behavior, rather than the strength criteria. Control of deflections under AISC specifications requirement is not enough to satisfy the serviceability requirements of the floor systems for vibration. In addition, vibration analysis procedures introduced by AISC design Guide No. 11 are based on regularly-shaped structures and simple boundary conditions. In this paper, a case study for full scale testing of a composite floor system proposed for a tower at Kuwait state that was tested prior to construction. The heel-drop and walking tests are performed on floor systems with and without raised floor respectively. Since heel-drop and walking test results would vary in light of person performance, both tests are carried out three or four times to reduce uncertainty. The fundamental frequencies and damping ratio of the floor system are measured. Comparison of the experimental results with results based on the AISC hand calculations shows that there is no significant difference; therefore the results based on AISC are generally acceptable.

The effects of mechanised equipment on physical load among road workers and floor layers in the construction industry

NARCIS (Netherlands)

Burdorf, A.; Windhorst, J.; Beek, A.J. van der; Molen, H. van der; Swuste, P.H.J.J.

2007-01-01

This study describes the impact of the use of mechanised equipment on physical load and workers' health among road workers and floor layers by comparing the traditional manual work method with frequently occurring scenarios of use of this new equipment. Continuous direct measurements of postures

Effect of Material Parameters on Steady State Creep in a Thick Composite Cylinder Subjected to Internal Pressure

Directory of Open Access Journals (Sweden)

Tejeet Singh

2009-12-01

Full Text Available The steady state creep in Al- SiCP composite cylinder subjected to internal pressure was investigated. The creep behavior of the material were described by threshold stress based creep law by assuming a stress exponent of 5. The effect of size and content of the reinforcement (SiCP , and operating temperature on the stresses and strain rates in the composite cylinder were investigated. The stresses in the cylinder did not have significant variation with varying size and content of the reinforcement, and operating temperature. However, the tangential as well as radial strain rates in the cylinder could be reduced to a significant extent by decreasing size of SiCP, increasing the content of SiCP and decreasing operating temperature.

Design by analysis of composite pressure equipment

International Nuclear Information System (INIS)

Durand, S.; Mallard, H.

2004-01-01

Design by analysis has been particularly pointed out by the european pressure equipment directive. Advanced mechanical analysis like finite element method are used instead of classical design by formulas or graphs. Structural behaviour can be understood by the designer. Design by analysis of metallic pressure equipments is widely used. Material behaviour or limits analysis is based on sophisticated approach (elasto-plastic analysis,..). Design by analysis of composite pressure equipments is not systematically used for industrial products. The difficulty comes from the number of information to handle. The laws of mechanics are the same for composite materials than for steel. The authors want to show that in design by analysis, the composite material approach is only more complete than the metallic approach. Mechanics is more general but not more complicated. A multi-material approach is a natural evolution of design by analysis of composite equipments. The presentation is illustrated by several industrial cases - composite vessel: analogy with metallic calculations; - composite pipes and fittings; - welding and bounding of thermoplastic equipments. (authors)

Analysis of Physical and Mechanical Properties of Marble Particles Floor-Tile Composite

International Nuclear Information System (INIS)

Parikin; Arslan, A.; Ismoyo, A.H.; Jodi, H.E.; Nurhasanah, S.

2002-01-01

Two criteria that very predictable to quality products of marble particles composite floor-tile are physical and mechanical properties. Simple manufacturing was conducted from powdering refuges of marble to molding and drying the specimens at ambient atmosphere. The characterization, to observe; density, crystal structure, microstructure, hardness and compressive/bending strength of the material, was performed in Serpong and IPB-Bogor. The analysis shows that polymeric crystallization was occurred by HEXA and the density and the hardness generally rise up with the improvements in mesh and composition of marble particles. But it is not always followed by the real improvements of compressive and bending strength, which related to the material stiffness. The curves figured that these two strengths give the maximum values at 60% composition of marble particles. It can be concluded that density and hardness are dependent on mesh and composition, whereas the stiffness (modulus) is only correlation with composition of particulate. The theoretical modulus of marble particles composite floor-tile has been evaluated at about 56.19 GPa. (author)

TEMPERATURE HETEROGENEITY OF TRAVELLING FIRE AND ITS INFLUENCE ON COMPOSITE STEEL-CONCRETE FLOOR

Directory of Open Access Journals (Sweden)

Kamila Horová

2016-04-01

Full Text Available In order to follow modern trends in contemporary building architecture, which is moving off the limits of current fire design models, assumption of homogeneous temperature conditions used for structural fire analysis needs to be revised. In this paper fire dynamics of travelling fire is investigated experimentally by conducting fire test in two-storey experimental building. To evaluate the impact of travelling fire on the mechanical behaviour of a structure, the spatial and temporal evolution of the gas temperature calculated in NIST code FDS, which was validated to experimental measurements, is applied to the composite floor of dimensions 9.0 m by 9.0 m. Mechanical behaviour of the composite slab highly affected by regions of high temperatures and areas with only elevated temperatures is solved in code Vulcan. To highlight the severity of spreading fire causing non-uniform temperature conditions, which after-effects differ from traditional methods, a comparison of both methods is introduced. The calculation of mechanical behaviour of the composite floor is repeated in a series of three different thermal loading cases. Results of all cases are then compared in terms of vertical displacement and axial force in several positions of the composite floor.

Crashworthiness Analysis and Evaluation of Fuselage Section with Sub-floor Composite Sinusoidal Specimens

Directory of Open Access Journals (Sweden)

H.L. Mou

Full Text Available Abstract Crashworthiness is one of the main concerns in civil aviation safety particularly with regard to the increasing ratio of carbon fiber reinforced plastic (CFRP in aircraft primary structures. In order to generate dates for model validations, the mechanical properties of T700/3234 were obtained by material performance tests, and energy-absorbing results were gained by quasi-static crushing tests of composite sinusoidal specimens. The correctness of composite material model and single-layer finite element model of composite sinusoidal specimens were verified based on the simulation results and test results that were in good agreement. A typical civil aircraft fuselage section with composite sinusoidal specimens under cargo floor was suggested. The crashworthiness of finite element model of fuselage section was assessed by simulating the vertical drop test subjected to 7 m/s impact velocity, and the influences of different thickness of sub-floor composite sinusoidal specimens on crashworthiness of fuselage section were also analyzed. The simulation results show that the established finite element model can accurately simulate the crushing process of composite sinusoidal specimens; the failure process of fuselage section is more stable, and the safety of occupants can be effectively improved because of the smaller peak accelerations that was limited to human tolerance, a critical thickness of sub-floor composite sinusoidal specimens can restrict the magnitude of acceleration peaks, which has certain reference values for enhancing crashworthiness capabilities of fuselage section and improving the survivability of passengers.

The provision of clearances accuracy in piston - cylinder mating

Science.gov (United States)

Glukhov, V. I.; Shalay, V. V.

2017-08-01

The paper is aimed at increasing the quality of the pumping equipment in oil and gas industry. The main purpose of the study is to stabilize maximum values of productivity and durability of the pumping equipment based on the selective assembly of the cylinder-piston kinematic mating by optimization criterion. It is shown that the minimum clearance in the piston-cylinder mating is formed by maximum material dimensions. It is proved that maximum material dimensions are characterized by their own laws of distribution within the tolerance limits for the diameters of the cylinder internal mirror and the outer cylindrical surface of the piston. At that, their dispersion zones should be divided into size groups with a group tolerance equal to half the tolerance for the minimum clearance. The techniques for measuring the material dimensions - the smallest cylinder diameter and the largest piston diameter according to the envelope condition - are developed for sorting them into size groups. Reliable control of the dimensions precision ensures optimal minimum clearances of the piston-cylinder mating in all the size groups of the pumping equipment, necessary for increasing the equipment productivity and durability during the production, operation and repair processes.

A heat mathematical model of polymer composite cylinder during microwave treatment

Directory of Open Access Journals (Sweden)

S. V. Reznik

2014-01-01

Full Text Available Traditional technologies of producing epoxy based polymer composite materials (PCM require a long-term and energy consuming thermal processing. Microwave heating could be used as an alternative technology for heating work pieces made of PCM; this would allow to reduce treatment time and energy consumption significantly. A mathematical model of temperature distribution inside a cylindrical composite system during microwave treatment was investigated in this paper. The model includes a hollow PCM cylinder made of an epoxy binder and carbon fibers and a solid cylindrical mandrel. Theoretical and experimental results on the temperature state of the system were analyzed and discussed.

Numerical Analysis of Prefabricated Steel-Concrete Composite Floor in Typical Lipsk Building

Directory of Open Access Journals (Sweden)

Lacki Piotr

2017-12-01

Full Text Available The aim of the work was to perform numerical analysis of a steel-concrete composite floor located in a LIPSK type building. A numerical model of the analytically designed floor was performed. The floor was in a six-storey, retail and service building. The thickness of a prefabricated slab was 100 mm. The two-row, crisscrossed reinforcement of the slab was made from φ16 mm rods with a spacing of 150 x 200 mm. The span of the beams made of steel IPE 160 profiles was 6.00 m and they were spaced every 1.20 m. The steelconcrete composite was obtained using 80×16 Nelson fasteners. The numerical analysis was carried out using the ADINA System based on the Finite Element Method. The stresses and strains in the steel and concrete elements, the distribution of the forces in the reinforcement bars and cracking in concrete were evaluated. The FEM model was made from 3D-solid finite elements (IPE profile and concrete slab and truss elements (reinforcement bars. The adopted steel material model takes into consideration the plastic state, while the adopted concrete material model takes into account material cracks.

Generate floor response spectra, Part 2: Response spectra for equipment-structure resonance

International Nuclear Information System (INIS)

Li, Bo; Jiang, Wei; Xie, Wei-Chau; Pandey, Mahesh D.

2015-01-01

Highlights: • The concept of tRS is proposed to deal with tuning of equipment and structures. • Established statistical approaches for estimating tRS corresponding to given GRS. • Derived a new modal combination rule from the theory of random vibration. • Developed efficient and accurate direct method for generating floor response spectra. - Abstract: When generating floor response spectra (FRS) using the direct spectra-to-spectra method developed in the companion paper, probability distribution of t-response spectrum (tRS), which deals with equipment-structure resonance or tuning, corresponding to a specified ground response spectrum (GRS) is required. In this paper, simulation results using a large number of horizontal and vertical ground motions are employed to establish statistical relationships between tRS and GRS. It is observed that the influence of site conditions on horizontal statistical relationships is negligible, whereas the effect of site conditions on vertical statistical relationships cannot be ignored. Considering the influence of site conditions, horizontal statistical relationship suitable for all site conditions and vertical statistical relationships suitable for hard sites and soft sites, respectively, are established. The horizontal and vertical statistical relationships are suitable to estimate tRS for design spectra in USNRC R.G. 1.60 and NUREG/CR-0098, Uniform Hazard Spectra (UHS) in Western North America (WNA), or any GRS falling inside the valid coverage of the statistical relationship. For UHS with significant high frequency spectral accelerations, such as UHS in Central and Eastern North America (CENA), an amplification ratio method is proposed to estimate tRS. Numerical examples demonstrate that the statistical relationships and the amplification ratio method are acceptable to estimate tRS for given GRS and to generate FRS using the direct method in different practical situations.

Generate floor response spectra, Part 2: Response spectra for equipment-structure resonance

Energy Technology Data Exchange (ETDEWEB)

Li, Bo, E-mail: b68li@uwaterloo.ca; Jiang, Wei, E-mail: w46jiang@uwaterloo.ca; Xie, Wei-Chau, E-mail: xie@uwaterloo.ca; Pandey, Mahesh D., E-mail: mdpandey@uwaterloo.ca

2015-11-15

Highlights: • The concept of tRS is proposed to deal with tuning of equipment and structures. • Established statistical approaches for estimating tRS corresponding to given GRS. • Derived a new modal combination rule from the theory of random vibration. • Developed efficient and accurate direct method for generating floor response spectra. - Abstract: When generating floor response spectra (FRS) using the direct spectra-to-spectra method developed in the companion paper, probability distribution of t-response spectrum (tRS), which deals with equipment-structure resonance or tuning, corresponding to a specified ground response spectrum (GRS) is required. In this paper, simulation results using a large number of horizontal and vertical ground motions are employed to establish statistical relationships between tRS and GRS. It is observed that the influence of site conditions on horizontal statistical relationships is negligible, whereas the effect of site conditions on vertical statistical relationships cannot be ignored. Considering the influence of site conditions, horizontal statistical relationship suitable for all site conditions and vertical statistical relationships suitable for hard sites and soft sites, respectively, are established. The horizontal and vertical statistical relationships are suitable to estimate tRS for design spectra in USNRC R.G. 1.60 and NUREG/CR-0098, Uniform Hazard Spectra (UHS) in Western North America (WNA), or any GRS falling inside the valid coverage of the statistical relationship. For UHS with significant high frequency spectral accelerations, such as UHS in Central and Eastern North America (CENA), an amplification ratio method is proposed to estimate tRS. Numerical examples demonstrate that the statistical relationships and the amplification ratio method are acceptable to estimate tRS for given GRS and to generate FRS using the direct method in different practical situations.

Can pulpal floor debonding be detected from occlusal surface displacement in composite restorations?

Science.gov (United States)

Novaes, João Batista; Talma, Elissa; Las Casas, Estevam Barbosa; Aregawi, Wondwosen; Kolstad, Lauren Wickham; Mantell, Sue; Wang, Yan; Fok, Alex

2018-01-01

Polymerization shrinkage of resin composite restorations can cause debonding at the tooth-restoration interface. Theory based on the mechanics of materials predicts that debonding at the pulpal floor would half the shrinkage displacement at the occlusal surface. The aim of this study is to test this theory and to examine the possibility of detecting subsurface resin composite restoration debonding by measuring the superficial shrinkage displacements. A commercial dental resin composite with linear shrinkage strain of 0.8% was used to restore 2 groups of 5 model Class-II cavities (8-mm long, 4-mm wide and 4-mm deep) in aluminum blocks (8-mm thick, 10-mm wide and 14-mm tall). Group I had the restorations bonded to all cavity surfaces, while Group II had the restorations not bonded to the cavity floor to simulate debonding. One of the proximal surfaces of each specimen was sprayed with fine carbon powder to allow surface displacement measurement by Digital Image Correlation. Images of the speckled surface were taken before and after cure for displacement calculation. The experiment was simulated using finite element analysis (FEA) for comparison. Group I showed a maximum occlusal displacement of 34.7±6.7μm and a center of contraction (COC) near the pulpal floor. Group II had a COC coinciding with the geometric center and showed a maximum occlusal displacement of 17.4±3.8μm. The difference between the two groups was statistically significant (p-value=0.0007). Similar results were obtained by FEA. The theoretical shrinkage displacement was 44.6 and 22.3μm for Group I and II, respectively. The lower experimental displacements were probably caused by slumping of the resin composite before cure and deformation of the adhesive layer. The results confirmed that the occlusal shrinkage displacement of a resin composite restoration was reduced significantly by pulpal floor debonding. Recent in vitro studies seem to indicate that this reduction in shrinkage displacement

Image analysis of moving seeds in an indented cylinder

DEFF Research Database (Denmark)

Buus, Ole; Jørgensen, Johannes Ravn

2010-01-01

inspection in seed cleaning equipment. A prototype of an indented cylinder will be constructed. To make it more dynamic, the cylinder itself will be manufactured using 3D printing technology. The input will come either from 3D scans of existing cylinders or by defining their topology using parametric B...

Influence of the stacking sequence of layers on the mechanical behavior of polymeric composite cylinders; Influencia da configuracao de bobinagem no comportamento mecanico de cilindros de composito polimerico

Energy Technology Data Exchange (ETDEWEB)

Carvalho, Osni de

2006-07-01

This work evaluated experimentally the influence of the stacking sequence of layers symmetrical and asymmetrical on the mechanical behavior of polymeric composite cylinders. For so much, two open-ended cylinders groups were manufactured by filament winding process, which had different stacking sequence related to the laminate midplane, characterizing symmetrical and asymmetrical laminates. The composite cylinders were made with epoxy matrix and carbon fiber as reinforcement. For evaluation of the mechanical strength, the cylinders were tested hydrostatically, which consisted of internal pressurization in a hydrostatic device through the utilization of a fluid until the cylinders burst. Additionally, were compared the strains and failure modes between the cylinders groups. The utilization of a finite element program allowed to conclude that this tool, very used in design, does not get to identify tensions in the fiber direction in each composite layer, as well as interlaminar shear stress, that appears in the cylinders with asymmetrical stacking sequence. The tests results showed that the stacking sequence had influence in the mechanical behavior of the composite cylinders, favoring the symmetrical construction. (author)

Magnetic levitation using high temperature superconducting pancake coils as composite bulk cylinders

International Nuclear Information System (INIS)

Patel, A; Hopkins, S C; Baskys, A; Glowacki, B A; Kalitka, V; Molodyk, A

2015-01-01

Stacks of superconducting tape can be used as composite bulk superconductors for both trapped field magnets and for magnetic levitation. Little previous work has been done on quantifying the levitation force behavior between stacks of tape and permanent magnets. This paper reports the axial levitation force properties of superconducting tape wound into pancake coils to act as a composite bulk cylinder, showing that similar stable forces to those expected from a uniform bulk cylinder are possible. Force creep was also measured and simulated for the system. The geometry tested is a possible candidate for a rotary superconducting bearing. Detailed finite element modeling in COMSOL Multiphysics was also performed including a full critical state model for induced currents, with temperature and field dependent properties and 3D levitation force models. This work represents one of the most complete levitation force modeling frameworks yet reported using the H-formulation and helps explain why the coil-like stacks of tape are able to sustain levitation forces. The flexibility of geometry and consistency of superconducting properties offered by stacks of tapes, make them attractive for superconducting levitation applications. (paper)

Solving decontaminable flooring problems

International Nuclear Information System (INIS)

Anon.

1989-01-01

Pennsylvania Power and Light wanted to cover deteriorating concrete in unit 2 of its Susquehanna BWR with a smooth, durable, decontaminable coating. Traditionally, floors in the plant had been coated with epoxy paint, but many of these floors suffered delamination, and failed in three to five years. Painting with epoxy would also interrupt operations for as much as three days while the floor dried, yet critical instruments in some areas had to be monitored at least once per shift. In addition, conventional floor surface preparation produced dust and vibration around sensitive equipment. The solution was a dustless scabbling system for surface preparation, followed by the installation of a high-strength acrylic industrial floor known as Silakal. The work was carried out by Pentek. Silikal bonds to the underlying concrete, so that delamination of the floor will not occur even under severe traffic conditions. Another advantage of this type of flooring is that it cures in one hour, so floor resurfacing has only minimal impact on plant operations. (author)

Frictional properties of lubrication greases with the addition of nickel nanoparticles in pneumatic cylinder

Science.gov (United States)

Chang, Ho; Lan, Chou-Wei; Guo, Jia-Bin

2011-12-01

This paper studies the influence of addition of 100 nm diameter nickel nano-particles on the friction properties of synthetic grease (Li base, VG100) in pneumatic cylinder. The friction force test of pneumatic cylinder equipment measures the frictional force between seal and cylinder bore in pneumatic cylinders. The lubricants with addition of nickel nano-particles were used for lubricating the contact interface between seal and cylinder bore. The friction force test equipment employ a load cell force sensor to measure the friction force between seals and cylinder bores. Results obtained from experimental tests are compared to determine the friction force between seals and cylinder bore in pneumatic cylinders. The study leads to the conclusion that the addition of nickel nano-particles to synthetic grease results in a decrease in friction force between seals and cylinder bores in pneumatic cylinder. This tribological behavior is closely related to the deposition of nano-particles on the rubbing surfaces

Seismic isolation floor and vibration control equipment for nuclear power plant

International Nuclear Information System (INIS)

Niwa, H.; Fujimoto, S.; Aida, Y.; Miyano, H.

1996-01-01

We have developed a seismic isolation floor to improve protection against earthquakes for process computer systems, and a magnetic dynamic damper to reduce the mechanical vibrations of piping systems and pumps in nuclear power plants. Seismic excitation tests of the seismic isolation floor, on which process computer systems were installed, were performed using large earthquake simulators. The test results proved that the seismic isolation floor significantly reduced seismic forces. To control mechanical vibrations, a magnetic dynamic damper was designed using permanent magnets. This magnetic dynamic damper does not require mechanical springs, dampers and supports in the floors and walls of the building. Vibration tests using a rotating machine model confirmed that the magnetic dynamic damper effectively controlled vibrations in such a rotating machine model. (author)

A study on the design of a low-friction, high-speed pneumatic cylinder

International Nuclear Information System (INIS)

Kim, Do Tae; Kim, Dong Soo; Ju, Min Jin

2008-01-01

Of all of pneumatic components utilized in the make up of pneumatic circuits on either automatic assembly machine or industrial equipment, the pneumatic cylinder is more oriented toward being a structural as well as a pneumatic member. The structural design must be based to a large degree on the end of application of the cylinder on the equipment it is operating. In this paper, design studies of a double-acting pneumatic cushion type cylinder with low-friction and high-speed driving have been developed. Of interest here is to investigate the structural analysis of cylinder tube, piston rod, end cover, and to analyze the buckling of piston rod. Also, a relief valve type cushion mechanism is considered. This cushion mechanism is found to be adequate under a high-speed driving of pneumatic cylinders

Test and Analysis of a Buckling-Critical Large-Scale Sandwich Composite Cylinder

Science.gov (United States)

Schultz, Marc R.; Sleight, David W.; Gardner, Nathaniel W.; Rudd, Michelle T.; Hilburger, Mark W.; Palm, Tod E.; Oldfield, Nathan J.

2018-01-01

Structural stability is an important design consideration for launch-vehicle shell structures and it is well known that the buckling response of such shell structures can be very sensitive to small geometric imperfections. As part of an effort to develop new buckling design guidelines for sandwich composite cylindrical shells, an 8-ft-diameter honeycomb-core sandwich composite cylinder was tested under pure axial compression to failure. The results from this test are compared with finite-element-analysis predictions and overall agreement was very good. In particular, the predicted buckling load was within 1% of the test and the character of the response matched well. However, it was found that the agreement could be improved by including composite material nonlinearity in the analysis, and that the predicted buckling initiation site was sensitive to the addition of small bending loads to the primary axial load in analyses.

Development of rationalized system treating floor drain

International Nuclear Information System (INIS)

Nakamura, Yasuyuki; Serizawa, Kenichi; Komatsu, Akihiro; Shimizu, Takayuki

1998-01-01

Radioactive liquid wastes generated at BWR plants are collected and treated as required. These days, however, generation of floor drain has deceased and HFF (Hollow Fiber Filter) has experienced a wide applicability to several kinds of liquid wastes. We should consider that the floor drain can be mixed and diluted with equipment drain and be purified by HFF. That enables some of the sumps and long priming pipes to be combined. From this point of view, we have developed a highly rationalized waste liquid system. We have evaluated the applicability of this system after an investigation into the generation and properties of floor drain and equipment drain at the latest BWR'S and an on-site test at a typical BWR. (author)

Application of Engineered Cementitious Composites (ECC) in modular floor panels

DEFF Research Database (Denmark)

Lárusson, Lárus Helgi; Fischer, Gregor; Jönsson, Jeppe

2008-01-01

This paper describes the design, manufacturing, and structural behavior of a prefabricated floor panel consisting of a modular assembly of a thin-walled ECC slab and steel truss girders. The features of this composite structure include light weight, the modular manufacturing process...... concept introduced in this paper aims at improvements in the manufacturing process of the panels by casting the ECC slab separately and subsequently joining it with the steel trusses. The focus of this paper is on design and manufacturing of a prototype modular panel and on its structural behavior under...

A Study of Gas Economizing Pneumatic Cylinder

International Nuclear Information System (INIS)

Li, T C; Wu, H W; Kuo, M J

2006-01-01

The pneumatic cylinder is the most typical actuator in the pneumatic equipment, and its mechanism is so simple that it is often used to operate point to point driving without the feedback loop in various automatic machines. But, the energy efficiency of pneumatic system is very poor compared with electrical systems and hydraulic systems. So, it is very important to discuss the energy saving for the pneumatic cylinder systems. In this thesis, we proposed three methods to apply the reduction in the air consumed for pneumatic cylinder systems. An air charge accumulator is used to absorb the exhausted compress air and a boost valve boosted the air to the higher pressure for used again. From the experiments, the direct used cylinder exhaust air may save about 40% of compress air

EXACT SOLUTION OF HEAT CONDUCTION IN A TWO-DOMAIN COMPOSITE CYLINDER WITH AN ORTHOTROPIC OUTER LAYER

International Nuclear Information System (INIS)

AVILES-RAMOS, C.; RUDY, C.

2000-01-01

The transient exact solution of heat conduction in a two-domain composite cylinder is developed using the separation of variables technique. The inner cylinder is isotropic and the outer cylindrical layer is orthotropic. Temperature solutions are obtained for boundary conditions of the first and second kinds at the outer surface of the orthotropic layer. These solutions are applied to heat flow calorimeters modeling assuming that there is heat generation due to nuclear reactions in the inner cylinder. Heat flow calorimeter simulations are carried out assuming that the inner cylinder is filled with plutonium oxide powder. The first objective in these simulations is to predict the onset of thermal equilibrium of the calorimeter with its environment. Two types of boundary conditions at the outer surface of the orthotropic layer are used to predict thermal equilibrium. The procedure developed to carry out these simulations can be used as a guideline for the design of calorimeters. Another important application of these solutions is on the estimation of thermophysical properties of orthotropic cylinders. The thermal conductivities in the vertical, radial and circumferential directions of the orthotropic outer layer can be estimated using this exact solution and experimental data. Simultaneous estimation of the volumetric heat capacity and thermal conductivities is also possible. Furthermore, this solution has potential applications to the solution of the inverse heat conduction problem in this cylindrical geometry. An interesting feature of the construction of this solution is that two different sets of eigenfunctions need to be considered in the eigenfunction expansion. These eigenfunctions sets depend on the relative values of the thermal diffusivity of the inner cylinder and the thermal diffusivity in the vertical direction of the outer cylindrical layer

The Present Status of Using Natural Gas Cylinders and Acoustic Emission in Thailand

Science.gov (United States)

Jomdecha, C.; Jirarungsatian, C.; Methong, W.; Poopat, B.

This chapter presents the status of using natural gas cylinders (CNG/NGV) and acoustic emission (AE) in Thailand. During the period from 2006 to 2013, more than 600,000 CNG cylinder units for vehicles were installed and used for transportation, cars, and trucks in Thailand. The number of cylinder units will be tentatively increased in the future due to the increase in gasoline price. Due to the use of high-pressurization equipment in public, the issue of a risk to public safety has been raised. As of this writing, in 2013, the testing standard from the Thai Department of Energy Business recommends inspection every 5 years using effective inspection methods in order to guarantee safe usage of gas cylinders, including the AE method, following ISO 16148. Normally in Thailand, AE is used in research and petrochemical plants as a special technique. The main applications are testing of pressure vessels, aboveground storage tanks, and university research. Few companies are available to conduct AE for testing natural gas cylinders due to the limited safety of the high-pressure operation and AE equipment and a lack of qualified AE personnel. To develop AE techniques, equipment, procedures, and acceptance criteria of natural gas cylinders are the main focus of AE personnel in Thailand. A desired achievement for current development is for natural gas cylinder testing, which can be applied in field tests and supported by a national testing standard.

Floor response spectra of buildings with uncertain structural properties

International Nuclear Information System (INIS)

Chen, P.C.

1975-01-01

All Category I equipment, such as reactors, vessels, and major piping systems of nuclear power plants, is required to withstand earthquake loadings in order to minimize risk of seismic damage. The equipment is designed by using response spectra of the floor on which the equipment is mounted. The floor response spectra are constructed usually from the floor response time histories which are obtained through a deterministic dynamic analysis. This analysis assumes that all structural parameters, such as mass, stiffness, and damping have been calculated precisely, and that the earthquakes are known. However, structural parameters are usually difficult to determine precisely if the structures are massive and/or irregular, such as nuclear containments and its internal structures with foundation soil incorporated into the analysis. Faced with these uncertainties, it has been the practice to broaden the floor response spectra peaks by +-10 percent of the peak frequencies on the basis of conservatism. This approach is based on engineering judgement and does not have an analytical basis to provide a sufficient level of confidence in using these spectra for equipment design. To insure reliable design, it is necessary to know structural response variations due to variations in structural properties. This consideration leads to the treatment of structural properties as random variables and the use of probabilistic methods to predict structural response more accurately. New results on floor response spectra of buildings with uncertain structural properties obtained by determining the probabilistic dynamic response from the deterministic dynamic response and its standard deviation are presented. The resulting probabilistic floor response spectra are compared with those obtained deterministically, and are shown to provide a more reliable method for determining seismic forces

Control of formaldehyde and TVOC emission from wood-based flooring composites at various manufacturing processes by surface finishing.

Science.gov (United States)

Kim, Sumin

2010-04-15

This paper assesses the reproducibility of testing formaldehyde and TVOC emission behavior from wood flooring composites bonded by urea-formaldehyde resin at various manufacturing steps for surface finishing materials. The surface adhesion step of laminate flooring for this research was divided into two steps; HDF only and HDF with LPMs. In the case of engineered flooring, the manufacturing steps were divided into three steps; plywood only, fancy veneer bonded on plywood and UV coated on fancy veneer with plywood. Formaldehyde and VOCs emission decreased at the process of final surface finishing materials; LPMs were applied on the surface of HDF for laminate flooring. Although emissions increased when fancy veneer was bonded onto plywood in the case of engineered flooring, emission was dramatically reduced up to similar level with plywood only when final surface finishing; UV-curable coating was applied on fancy veneer. This study suggests that formaldehyde and VOCs emission from floorings can be controlled at manufacturing steps for surface finishing. 2009 Elsevier B.V. All rights reserved.

Evaluation of new composite rigid joint under cyclic loading and its effect on one-floor composite frame

Directory of Open Access Journals (Sweden)

Azadeh Haghighat

2017-08-01

Full Text Available In order to improve the performance of structure against lateral and gravity loads, new systems known as composite systems consisting of the reinforced concrete columns and steel beams (RCS can be used and thereby the advantages of concrete beside steel are acquired. RCS joints can be implemented as either through-beam-type joint or through-column-type joint. In this paper, a concrete joint as standard reference joint and a proposed composite joint through-column‎ with new details were built and tested under cyclic loading. Then, using numerical analysis by finite element method, the behavior of composite joint under cyclic loading has been studied and the behavior and performance of proposed composite joint has been studied by comparing the results with that of concrete joint. The results showed that the joint composition in this way resulted in decreasing of the compressive and tensile damages of concrete and increasing in loading capacity, ductility, stiffness and energy absorption. General results of application of composite joint at the one floor-one span composite frame indicating that lateral loading capacity of frame was increased and the performance of frame was improved.

Generation of floor spectra compatible time histories for equipment seismic qualification in nuclear power plants

International Nuclear Information System (INIS)

Shyu, Y.-S.; Luh, Gary G.; Blum, Arie

2004-01-01

This paper proposes a procedure for generating floor response spectra compatible time histories used for equipment seismic qualification in nuclear power plants. From the 84th percentile power spectrum density function of an earthquake ensemble of four randomly generated time history motions, a statistically equivalent time history can be obtained by converting the power spectrum density function from the frequency domain into the time domain. With minor modification, if needed, the converted time history will satisfy both the spectral and the power spectrum density enveloping criteria, as required by the USNRC per Revision 2 of the Standard Review Plan, Section 3.7.1. Step-by-step generating procedures and two numerical examples are presented to illustrate the applications of the methodology. (author)

Equipment for capping drums, especially with radioactive waste

International Nuclear Information System (INIS)

Bednarik, F.

1987-01-01

The equipment consists of a pneumatic cylinder, lever systems with jaws, guide bars, and of securing pins. The top cylinder lid and the bottom cylinder lid provided with openings are slidably attached to a shaft firmly connected to a piston and a support plate. Firmly attached to the bottom lid using brackets are pins holding connecting rods controlling the double-arm levers pivoted on pins, featuring jaws pivoted on forks firmly attached to the support plate and provided with a replaceable spacer insert. The guide bars are firmly attached to the support plate via braces and stiffeners. The securing pins are loaded with springs seated in the braces. The benefits of the equipment include that the lid closing levers with jaws, mechanically controlled using one pneumatic cylinder, thanks to their number and configuration, close the lid around the drum border provided with small recesses which do not reach above the circumference of the drum being closed. The equipment can also be used for carrying closed drums, this also during compressed air failures because the levers with jaws are secured in position with the pneumatic cylinder leg. (J.B.). 1 fig

Analytical prediction of the interior noise for cylindrical models of aircraft fuselages for prescribed exterior noise fields. Phase 2: Models for sidewall trim, stiffened structures and cabin acoustics with floor partition

Science.gov (United States)

Pope, L. D.; Wilby, E. G.

1982-01-01

An airplane interior noise prediction model is developed to determine the important parameters associated with sound transmission into the interiors of airplanes, and to identify apropriate noise control methods. Models for stiffened structures, and cabin acoustics with floor partition are developed. Validation studies are undertaken using three test articles: a ring stringer stiffened cylinder, an unstiffened cylinder with floor partition, and ring stringer stiffened cylinder with floor partition and sidewall trim. The noise reductions of the three test articles are computed using the heoretical models and compared to measured values. A statistical analysis of the comparison data indicates that there is no bias in the predictions although a substantial random error exists so that a discrepancy of more than five or six dB can be expected for about one out of three predictions.

Seismic and dynamic qualification of safety-related electrical and mechanical equipment in operating nuclear power plants: development of a method to generate generic floor-response spectra

International Nuclear Information System (INIS)

Curreri, J.; Costantino, C.; Subudhi, M.; Reich, M.

1983-09-01

Generic floor response spectra were developed for use in the qualification of electrical and mechanical equipment in operating nuclear power plants. The characteristics of 1000 floor response spectra were studied to determine the generic spectra. The procedure developed uses as much or as little information that currently exists at the plant relating to the question of equipment qualification. The general approach was to study the effects on the dynamic characteristics of each of the elements in the chain of events that goes between the loads and the responses. This includes the loads, the soils and the structures. A free-field earthquake response spectra was used to generate horizontal earthquake time histories. The excitation was applied through the soil and into the various structures to produce responses in equipment. An entire range of soil conditions was used with each structure. Actual PWR and BWR - Mark I structural models were used. For each model, the stiffness properties were varied, with the same mass, so as to extend the fundamental base structure natural frequency from 2 cps to 36 cps. The natural frequencies of the structures were varied to obtain maximum response conditions. The actual properties were first used to locate the natural frequencies. The stiffness properties were than varied, with the same mass, to extend the range of the fundamental base structure natural frequency. The intention was to have the coupled structural material frequencies in the vicinity of the peak amplitude frequency content of the excitation spectrum. Particular attention was therefore given to the frequency band between 2 Hz and 4 Hz. A horizontal generic floor response spectra is proposed for the top level of a generic structure. Reduction factors are applied to the peak acceleration for equipment at lower levels

The use of artificial neural networks for mathematical modeling of the effect of composition and production conditions on the properties of PVC floor coverings

Directory of Open Access Journals (Sweden)

Radovanović Rajko M.

2017-01-01

Full Text Available The application of PVC floor coverings is strongly connected with their end-use properties, which depend on the composition and processing conditions. It is very difficult to estimate the proper influence of the production parameters on the characteristics of PVC floor coverings due to their complex composition and various preparation procedures. The effect of different processing variables (such as time of bowling, temperature of bowling and composition of PVC plastisol on the mechanical properties of PVC floor coverings was investigated. The influence of different input parameters on the mechanical properties was successfully determined using an artificial neural network with an optimized number of hidden neurons. The Garson and Yoon models were applied to calculate and describe the variable contributions in the artificial neural networks. [Projekat Ministarstva nauke Republike Srbije, br. III 45022

BP volume reduction equipment

International Nuclear Information System (INIS)

Kitamura, Yoshinori; Muroo, Yoji; Hamanaka, Isao

2003-01-01

A new type of burnable poison (BP) volume reduction system is currently being developed. Many BP rods, a subcomponent of spent fuel assemblies are discharged from nuclear power reactors. This new system reduces the overall volume of BP rods. The main system consists of BP rod cutting equipment, equipment for the recovery of BP cut pieces, and special transport equipment for the cut rods. The equipment is all operated by hydraulic press cylinders in water to reduce operator exposure to radioactivity. (author)

Application of sandwich honeycomb carbon/glass fiber-honeycomb composite in the floor component of electric car

Science.gov (United States)

Sukmaji, I. C.; Wijang, W. R.; Andri, S.; Bambang, K.; Teguh, T.

2017-01-01

Nowadays composite is a superior material used in automotive component due to its outstanding mechanical behavior. The sandwich polypropylene honeycomb core with carbon/glass fiber composite skin (SHCG) as based material in a floor component of electric car application is investigated in the present research. In sandwich structure form, it can absorb noise better compare with the conventional material [1]. Also in present paper, Finite Element Analysis (FEA) of SHCG as based material for floor component of the electric car is analyzed. The composite sandwich is contained with a layer uniform carbon fiber and mixing non-uniform carbon-glass fiber in upper and lower skin. Between skins of SHCG are core polypropylene honeycomb that it have good flexibility to form following dies profile. The variables of volume fraction ratio of carbon/glass fiber in SHCG skin are 20/80%, 30/70%, and 50/50%. The specimen of SHCG is tested using the universal testing machine by three points bending method refers to ASTM C393 and ASTM C365. The cross point between tensile strength to the volume fraction the mixing carbon/glass line and ratio cost line are the searched material with good mechanical performance and reasonable cost. The point is 30/70 volume fraction of carbon/glass fiber. The result of the testing experiment is become input properties of model structure sandwich in FEA simulation. FEA simulation approach is conducted to find critical strength and factor of complex safety geometry against varied distributed passenger loads of a floor component the electric car. The passenger loads variable are 80, 100, 150, 200, 250 and 300 kg.

Experimental Tests on Bending Behavior of Profiled Steel Sheeting Dry Board Composite Floor with Geopolymer Concrete Infill

Directory of Open Access Journals (Sweden)

Mohd Isa Jaffar

Full Text Available Abstract Profiled Steel Sheet Dry Board (PSSDB system is a lightweight composite structure comprises Profiled Steel Sheeting and Dry Board connected by self-drilling and self-tapping screws. This study introduced geopolymer concrete, an eco-friendly material without cement content as an infill material in the PSSDB floor system to highlight its effect onto the PSSDB (with full and half-size dry boards floor system's stiffness and strength. Experimental tests on various full scale PSSDB floor specimens were conducted under uniformly distributed transverse loads. Results illustrate that the rigidity of the panel with geopolymer concrete infill with half-size dry board (HBGPC increases by 43% relative to that of the panel with normal concrete infill with full-size dry board (FBNC. The developed finite-element modeling (FEM successfully predicts the behavior of FBGPC model with 94.8% accuracy. Geopolymer concrete infill and dry board size influence the strength panel, infill contact stiffness, and mid-span deflection of the profiled steel sheeting/dry board (PSSDB flooring system.

Gut microbiota composition is correlated to grid floor induced stress and behavior in the BALB/c mouse

DEFF Research Database (Denmark)

Bendtsen, Katja Maria Bangsgaard; Krych, Lukasz; Sørensen, Dorte Bratbo

2012-01-01

to grid floor. Stressing the mice clearly changed the cecal microbiota as determined by both DGGE and pyrosequencing. Odoribacter, Alistipes and an unclassified genus from the Coriobacteriaceae family increased significantly in the grid floor housed mice. Compared to baseline, the mice exposed to grid......Stress has profound influence on the gastro-intestinal tract, the immune system and the behavior of the animal. In this study, the correlation between gut microbiota composition determined by Denaturing Grade Gel Electrophoresis (DGGE) and tag-encoded 16S rRNA gene amplicon pyrosequencing (454/FLX......) and behavior in the Tripletest (Elevated Plus Maze, Light/Dark Box, and Open Field combined), the Tail Suspension Test, and Burrowing in 28 female BALB/c mice exposed to two weeks of grid floor induced stress was investigated. Cytokine and glucose levels were measured at baseline, during and after exposure...

Some Passive Damping Sources on Flooring Systems besides the TMD

DEFF Research Database (Denmark)

Pedersen, Lars

2010-01-01

Impulsive loads and walking loads can generate problematic structural vibrations in flooring-systems. Measures that may be taken to mitigate the problem would often be to consider the implementation of a tuned mass damper or even more advanced vibration control technologies; this in order to add...... damping to the structure. Basically also passive humans on a floor act as a damping source, but it also turns out from doing system identification tests with a floor strip that a quite simple set-up installed on the floor (cheap and readily at hand) might do a good job in terms of reducing vertical floor...... vibrations for some floors. The paper describes the tests with the floor strip, and the results, in terms of dynamic floor behaviour, are compared with what would be expected had the floor instead been equipped with a tuned mass damper....

700 bar hydrogen cylinder design, testing and certification

International Nuclear Information System (INIS)

Duncan, M.

2004-01-01

'Full text:' Light weight and high pressure cylinders for compressed hydrogen storage are essential components for fuel cell vehicles. Storage volume and mass are two key considerations. Current on-board hydrogen storage systems are based on a maximum pressure of 350 bar. While 350 bar systems are excellent solutions for many applications, some situations required higher storage densities due to space restrictions. As a result significant research and development work has been expended by cylinder manufacturers, systems providers, testing agencies and automotive manufacturers to develop 700 bar systems to reduce storage volume. Dynetek Industries Ltd has proactively developed a range of 700 bar storage cylinders based on a seamless aluminum liner over wrapped with a carbon fiber composite. This paper presents the challenges and processes involved in the design, testing and certification of the Dynetek Industries Ltd 700 bar cylinder. The paper also provides reasoning for further volume and mass optimization of compressed hydrogen cylinders by incorporating realistic cylinder usage parameters into standards. In particular the overly conservative fill life requirement for cylinders will be examined. (author)

30 CFR 75.1106-2 - Transportation of liquefied and nonliquefied compressed gas cylinders; requirements.

Science.gov (United States)

2010-07-01

... underground coal mine shall be: (1) Placed securely in devices designed to hold the cylinder in place during transit on self-propelled equipment or belt conveyors; (2) Disconnected from all hoses and gages; (3... containers which are specifically designed for holding such cylinders. (c) Liquefied and nonliquefied...

Generation of equipment response spectrum considering equipment-structure interaction

International Nuclear Information System (INIS)

Lee, Sang Hoon; Yoo, Kwang Hoon

2005-01-01

Floor response spectra for dynamic response of subsystem such as equipment, or piping in nuclear power plant are usually generated without considering dynamic interaction between main structure and subsystem. Since the dynamic structural response generally has the narrow-banded shapes, the resulting floor response spectra developed for various locations in the structure usually have high spectral peak amplitudes in the narrow frequency bands corresponding to the natural frequencies of the structural system. The application of such spectra for design of subsystems often leads to excessive design conservatisms, especially when the equipment frequency and structure are at resonance condition. Thus, in order to provide a rational and realistic design input for dynamic analysis and design of equipment, dynamic equipment-structure interaction (ESI) should be considered in developing equipment response spectrum which is particularly important for equipment at the resonance condition. Many analytical methods have been proposed in the past for developing equipment response spectra considering ESI. However, most of these methods have not been adapted to the practical applications because of either the complexities or the lack of rigorousness of the methods. At one hand, mass ratio among the equipment and structure was used as an important parameter to obtain equipment response spectra. Similarly, Tseng has also proposed the analytical method for developing equipment response spectra using mass ratio in the frequency domain. This method is analytically rigorous and can be easily validated. It is based on the dynamic substructuring method as applied to the dynamic soil-structure interaction (SSI) analysis, and can relatively easily be implemented for practical applications without to change the current dynamic analysis and design practice for subsystems. The equipment response spectra derived in this study are also based on Tseng's proposed method

Sound insulation of composite cylindrical shells: a comparison between a laminated and a sandwich cylinder

OpenAIRE

Yuan, Chongxin; Roozen, Bert; Bergsma, Otto; Beukers, Adriaan

2012-01-01

The fuselages of aircraft are modeled as a cylinder in this paper, and the sound insulations of a sandwich cylinder and a laminated cylinder are studied both experimentally and numerically. The cylinders are excited by an acoustic pressure and a mechanical force respectively. Results show that under acoustic excitation, the sandwich cylinder and the laminated one have a similar sound insulation below 3000 Hz, but the sandwich cylinder has a much larger sound insulation at higher frequencies. ...

Element nodes of sports equipment double back flip factions and double back flip hunched performed gymnast in floor exercise

Directory of Open Access Journals (Sweden)

V.A. Potop

2014-07-01

Full Text Available Purpose: to identify the node elements of sports equipment double back somersault tuck and double back flip bent. To compare the two types of nodes for double somersault. Material : the study involved eight gymnasts (age 12 - 14 years. All finalists in the competition floor exercise - reserve team Romania. The method of video - computer research and method of postural orientation movements. Results : identified nodal elements of sports equipment double back somersault tuck and double back flip bent. In the preparatory phase of motor actions - launcher body posture for reaching is repulsive to flip. In the phase of basic motor action - animation body postures (double back somersault tuck and bent (bent double back flip. Exercises are performed on the ascending and descending parts of the flight path of the demonstration of individual maximum lift height common center of mass. In the final phase of motor actions - final body posture - steady landing. Conclusions : indicators of key elements of sports equipment acrobatic exercises contain new scientific facts kinematic and dynamic structures of motor actions. They are necessary for the development of modern training programs acrobatic exercises in step specialized base preparation.

Composition and fundamental requirements of nuclear emergency response monitoring equipment

International Nuclear Information System (INIS)

Lai Yongfang; Huang Weiqi; Wang Yonghong

2009-01-01

Nuclear emergency monitoring equipment is concrete foundation for accomplishing radiation monitoring in nuclear or radiation accidents. Based on technical report: Generic procedures for monitoring in a nuclear or radiological emergency published by IAEA in 1999, this paper presents the main task and composition of nuclear emergency monitoring briefly, and then the basic equipment and trends of nuclear emergency monitoring equipment is put forward in detail, which is useful to construction and reinforcement of our nuclear emergency monitoring. (authors)

Gas cylinder disposal pit remediation waste minimization and management

International Nuclear Information System (INIS)

Alas, C.A.; Solow, A.; Criswell, C.W.; Spengler, D.; Brannon, R.; Schwender, J.M.; Eckman, C.K.; Rusthoven, T.

1995-01-01

A remediation of a gas cylinder disposal pit at Sandia National Laboratories, New Mexico has recently been completed. The cleanup prevented possible spontaneous releases of hazardous gases from corroded cylinders that may have affected nearby active test areas at Sandia's Technical Area III. Special waste management, safety, and quality plans were developed and strictly implemented for this project. The project was conceived from a waste management perspective, and waste minimization and management were built into the planning and implementation phases. The site layout was planned to accommodate light and heavy equipment, storage of large quantities of suspect soil, and special areas to stage and treat gases and reactive chemicals removed from the pit, as well as radiation protection areas. Excavation was a tightly controlled activity using experienced gas cylinder and reactive chemical specialists. Hazardous operations were conducted at night under lights, to allow nearby daytime operations to function unhindered. The quality assurance plan provided specific control of, and documentation for, critical decisions, as well as the record of daily operations. Both hand and heavy equipment excavation techniques were utilized. Hand excavation techniques were utilized. Hand excavation techniques allows sealed glass containers to be exhumed unharmed. In the end, several dozen thermal batteries; 5 pounds (2.3 kg) of lithium metal; 6.6 pounds (3.0 kg) of rubidium metal; several kilograms of unknown chemicals; 140 cubic yards (107 cubic meters) of thorium-contaminated soil; 270 cubic yards (205 cubic meters) of chromium-contaminated soil; and 450 gas cylinders, including 97 intact cylinders containing inert, flammable, toxic, corrosive, or oxidizing gases were removed and effectively managed to minimize waste

Cost-Benefit Analysis for the Advanced Near Net Shape Technology (ANNST) Method for Fabricating Stiffened Cylinders

Science.gov (United States)

Ivanco, Marie L.; Domack, Marcia S.; Stoner, Mary Cecilia; Hehir, Austin R.

2016-01-01

Low Technology Readiness Levels (TRLs) and high levels of uncertainty make it challenging to develop cost estimates of new technologies in the R&D phase. It is however essential for NASA to understand the costs and benefits associated with novel concepts, in order to prioritize research investments and evaluate the potential for technology transfer and commercialization. This paper proposes a framework to perform a cost-benefit analysis of a technology in the R&D phase. This framework was developed and used to assess the Advanced Near Net Shape Technology (ANNST) manufacturing process for fabricating integrally stiffened cylinders. The ANNST method was compared with the conventional multi-piece metallic construction and composite processes for fabricating integrally stiffened cylinders. Following the definition of a case study for a cryogenic tank cylinder of specified geometry, data was gathered through interviews with Subject Matter Experts (SMEs), with particular focus placed on production costs and process complexity. This data served as the basis to produce process flowcharts and timelines, mass estimates, and rough order-of-magnitude cost and schedule estimates. The scalability of the results was subsequently investigated to understand the variability of the results based on tank size. Lastly, once costs and benefits were identified, the Analytic Hierarchy Process (AHP) was used to assess the relative value of these achieved benefits for potential stakeholders. These preliminary, rough order-of-magnitude results predict a 46 to 58 percent reduction in production costs and a 7-percent reduction in weight over the conventional metallic manufacturing technique used in this study for comparison. Compared to the composite manufacturing technique, these results predict cost savings of 35 to 58 percent; however, the ANNST concept was heavier. In this study, the predicted return on investment of equipment required for the ANNST method was ten cryogenic tank barrels

An analytical/numerical correlation study of the multiple concentric cylinder model for the thermoplastic response of metal matrix composites

Science.gov (United States)

Pindera, Marek-Jerzy; Salzar, Robert S.; Williams, Todd O.

1993-01-01

The utility of a recently developed analytical micromechanics model for the response of metal matrix composites under thermal loading is illustrated by comparison with the results generated using the finite-element approach. The model is based on the concentric cylinder assemblage consisting of an arbitrary number of elastic or elastoplastic sublayers with isotropic or orthotropic, temperature-dependent properties. The elastoplastic boundary-value problem of an arbitrarily layered concentric cylinder is solved using the local/global stiffness matrix formulation (originally developed for elastic layered media) and Mendelson's iterative technique of successive elastic solutions. These features of the model facilitate efficient investigation of the effects of various microstructural details, such as functionally graded architectures of interfacial layers, on the evolution of residual stresses during cool down. The available closed-form expressions for the field variables can readily be incorporated into an optimization algorithm in order to efficiently identify optimal configurations of graded interfaces for given applications. Comparison of residual stress distributions after cool down generated using finite-element analysis and the present micromechanics model for four composite systems with substantially different temperature-dependent elastic, plastic, and thermal properties illustrates the efficacy of the developed analytical scheme.

Floor-Fractured Craters on Ceres and Implications for Internal Composition and Processes

Science.gov (United States)

Buczkowski, D.; Schenk, P.; Scully, J. E. C.; Park, R. S.; Preusker, F.; Raymond, C. A.; Russell, C. T.

2016-12-01

Several of the impact craters on Ceres have patterns of fractures on their floors. These fractures appear similar to those found within a class of lunar craters referred to as Floor-Fractured Craters (FFCs) [1]. Lunar FFCs are characterized by anomalously shallow floors cut by radial, concentric, and/or polygonal fractures, and have been classified into crater classes, Types 1 through 6, based on their morphometric properties [1,2]. Models for their formation have included both floor uplift due to magmatic intrusion below the crater or floor shallowing due to viscous relaxation. However, the observation that the depth versus diameter (d/D) relationship of the FFCs is distinctly shallower than the same association for other lunar craters supports the hypotheses that the floor fractures form due to shallow magmatic intrusion under the crater [2]. We have cataloged the Ceres FFCs according to the classification scheme designed for the Moon. Large (>50 km) Ceres FFCs are most consistent with Type 1 lunar FFCs, having deep floors, central peaks, wall terraces, and radial and/or concentric fractures. Smaller craters on Ceres are more consistent with Type 4 lunar FFCs, having less-pronounced floor fractures and v-shaped moats separating the wall scarp from the crater interior. An analysis of the d/D ratio for Ceres craters shows that, like lunar FFCs, the Ceres FFCs are anomalously shallow. This suggests that the fractures on the floor of Ceres FFCs may be due the intrusion of a low-density material below the craters that is uplifting their floors. While on the Moon the intrusive material is hypothesized to be silicate magma, this is unlikely for Ceres. However, a cryovolcanic extrusive edifice has been identified on Ceres [3], suggesting that cryomagmatic intrusions could be responsible for the formation of the Ceres FFCs. References: [1] Schultz P. (1976) Moon, 15, 241-273 [2] Jozwiak L.M. et al (2015) JGR 117, doi: 10.1029/2012JE004134 [3] Ruesch O. et al (2016

ABOUT WAVEFORM OF BRAKING CYLINDER FILLING IN FREIGHT CARS

Directory of Open Access Journals (Sweden)

L. V. Ursuliak

2016-04-01

Full Text Available Purpose. As part of the scientific paper it is necessary to study the waveform impact of the braking cylinders filling on longitudinal train dynamics at different modes of braking. At this one should estimate the level of maximum longitudinal forces and braking distance size in freight cars of various lengths. Methodology. In this paper we attempt to approximate the actual diagram of braking cylinders filling with rational functions of varying degrees. In selection of coefficients in the required functions the highest values of the longitudinal forces and braking distances were used as controlled parameters. They were compared with similar values obtained as a result of experimental rides. The level of longitudinal forces and braking distances amount were evaluated by means of mathematical modeling of train longitudinal vibrations, caused by different braking modes. Findings. At mathematical modeling was assumed that the train consists of 60 uniform four-axle gondola cars, weight of 80 tons, equipped with air dispenser No. 483 included in the median operation, composite braking blocks, and one locomotive VL-8. Train before braking has been pre-stretched. Various types of pneumatic braking (emergency, full service and adjusting braking of the freight train on the horizontal section of the track were simulated. As the calculation results were obtained values of the longitudinal forces, braking distances amounts and reduction time in speed at various braking modes. Originality. Waveform impact of the braking cylinders filling on the longitudinal forces level and braking distances amount in freight trains were investigated. Also the longitudinal loading of freight trains at various pneumatic braking was investigated. Practical value. Obtained results can be used to assess the level of largest longitudinal forces and braking distances in the freight trains of different lengths by mathematical modeling of different braking modes.

Coatings and floor covers for nuclear applications

International Nuclear Information System (INIS)

Kunze, S.

1998-01-01

To prevent damage to, or even the destruction of, components of very sensitive electrical equipment in rooms in which unsealed radioactive emitters are handled, floors must be antistatic and capable of being decontaminated. Conductive additives to the cover compounds achieve the desired leakage resistance of 5.10 4 to 10 6 Ω. Investigations have shown the decontamination capability of all floor covers and coatings to be excellent in most cases, and good in a few cases. Except for one coating, the coatings examined after radiation exposure also meet the requirements applying to nuclear installations. (orig.) [de

Flexible organization of floor composition and flexible organization of dwelling space as a response to contemporary market demands

OpenAIRE

Jovanović Goran

2007-01-01

The paper presents the application of the principle of flexibility of architectonic space on the concrete example of flat composition. This example demonstrates that with a proper choice of structural spans dimensions and regular arrangement of sanitary and ventilation vertical assemblies, a structure with high flexibility in terms of flat space organization and floor space organization, can be achieved.

Heat convection in a set of three vertical cylinders

International Nuclear Information System (INIS)

Serrano Ramirez, M.L. de.

1993-01-01

Experimental results on temperature and heat flow in a set of three vertical cylinders with internal generation of heat, water submerged and in free convection are presented in this work . Temperature distribution, Nusselt number and convective coefficient (h) for each rod, developed for the distance between the axis of cylinders in vertical position, as a consequence of the application of power in its outside, are analyzed. Experimental information about heat transfer by free convection in vertical cylinders and surfaces is analyzed. Information of the several author who have carried out studies about the heat transfer on vertical cylinders was compiled, and the proposed equations with the experimental data obtained in the thermo fluids laboratory of National Institute of Nuclear Research (ININ) were tested. The way in which separation distance, s, distribution temperature array, Nusselt number, and convective coefficient calculated for the proposed channel with the Keyhani, Dutton and experimental equations are tabulated and they are plotted for each power value and for each separation between rods. The scheme of the used equipment and the experimentation description as well as the observations of tests and graphical results are included. (Author)

Flow around a cylinder surrounded by a permeable cylinder in shallow water

Energy Technology Data Exchange (ETDEWEB)

Ozkan, Gokturk M.; Akilli, Huseyin; Sahin, Besir [Cukurova University, Department of Mechanical Engineering, Faculty of Engineering and Architecture, Adana (Turkey); Oruc, Vedat [Dicle University, Department of Mechanical Engineering, Diyarbakir (Turkey)

2012-12-15

The change in flow characteristics downstream of a circular cylinder (inner cylinder) surrounded by an outer permeable cylinder was investigated in shallow water using particle image velocimetry technique. The diameter of the inner cylinder and the water height were kept constant during the experiments as d=50 mm and h{sub w}=25 mm, respectively. The depth-averaged free-stream velocity was also kept constant as U=170 mm/s which corresponded to a Reynolds number of Re{sub d}=8,500 based on the inner cylinder diameter. In order to examine the effect of diameter and porosity of the outer cylinder on flow characteristics of the inner cylinder, five different outer cylinder diameters (D=60, 70, 80, 90 and 100 mm) and four different porosities ({beta}=0.4, 0.5, 0.6 and 0.7) were used. It was shown that both porosity and outer cylinder diameter had a substantial effect on the flow characteristics downstream of the circular cylinder. Turbulent statistics clearly demonstrated that in comparison with the bare cylinder (natural case), turbulent kinetic energy and Reynolds stresses decreased remarkably when an outer cylinder was placed around the inner cylinder. Thereby, the interaction of shear layers of the inner cylinder has been successfully prevented by the presence of outer cylinder. It was suggested by referring to the results that the outer cylinder having 1.6{<=}D/d{<=}2.0 and 0.4{<=}D/d{<=}0.6 should be preferred to have a better flow control in the near wake since the peak magnitude of turbulent kinetic energy was considerably low in comparison with the natural case and it was nearly constant for these mentioned porosities {beta}, and outer cylinder to inner cylinder diameter ratios D/d. (orig.)

Finite element analysis of high modal dynamic responses of a composite floor subjected to human motion under passive live load

Directory of Open Access Journals (Sweden)

Arash Behnia

Full Text Available Light weight and long span composite floors are common place in modern construction. A critical consequence of this application is undesired vibration which may cause excessive discomfort to occupants. This work investigates the composite floor vibration behavior of an existing building based on a comprehensive study of high modal dynamic responses, the range of which has been absent in previous studies and major analytical templates, of different panels under the influence of loads induced by human motion. The resulting fundamental natural frequency and vibration modes are first validated with respect to experimental and numerical evidences from literature. Departing from close correlation established in comparison, this study explores in detail the effects of intensity of passive live load as additional stationary mass due to crowd jumping as well as considering human structure interaction. From observation, a new approach in the simulation of passive live load through the consideration of human structure interaction and human body characteristics is proposed. It is concluded that higher vibration modes are essential to determine the minimum required modes and mass participation ratio in the case of vertical vibration. The results indicate the need to consider 30 modes of vibration to obtain all possible important excitations and thereby making third harmonic of load frequency available to excite the critical modes. In addition, presence of different intensities of passive live load on the composite floor showed completely different behavior in each particular panel associated with load location of panel and passive live load intensity. Furthermore, implementing human body characteristics in simulation causes an obvious increase in modal damping and hence better practicality and economical presentation can be achieved in structural dynamic behavior.

Experimental investigation of turbulent flow past four grooved and smooth cylinders in an in-line square arrangement

Directory of Open Access Journals (Sweden)

Ladjedel O.

2015-01-01

Full Text Available An experimental study of turbulent flow past four cylinders in square arrangement with a space ratio of (T/D = P/D = 2.88 is performed. The investigation focuses on effects of Reynolds number and the shape of cylinders on the force and pressure coefficients of the cylinders. Two cases are investigated: four smooth cylinders (case1 and four grooved cylinders (case2. The cylinders are equipped with two grooves placed on the external surface at 90° and 270° degrees. The pressure distributions along the tubes (22 circumferential pressure taping were determined for a variation of the azimuthal angle from 0 to 360deg. The drag and lift forces are measured using the TE 44 balance. The results show a bistable flow often exists behind the downstream cylinders is observed. By rising the Reynolds number the pressure coefficient increases in the absolute value.

Low-cost, low-weight CNG cylinder development. Final report

Energy Technology Data Exchange (ETDEWEB)

Richards, Mark E.; Melford, K.; Wong, J.; Gambone, L.

1999-09-01

This program was established to develop and commercialize new high-strength steel-lined, composite hoop-wrapped compressed natural gas (CNG) cylinders for vehicular applications. As much as 70% of the cost of natural gas vehicles can be related to on-board natural gas storage costs. The cost and weight targets for this program represent significant savings in each characteristic when compared to comparable containers available at the initiation of the program. The program objectives were to optimize specific weight and cost goals, yielding CNG cylinders with dimensions that should, allowing for minor modifications, satisfy several vehicle market segments. The optimization process encompassed material, design, and process improvement. In optimizing the CNG cylinder design, due consideration was given to safety aspects relative to national, international, and vehicle manufacturer cylinder standards and requirements. The report details the design and development effort, encompassing plant modifications, material selection, design issues, tooling development, prototype development, and prototype testing. Extenuating circumstances prevented the immediate commercialization of the cylinder designs, though significant progress was made towards improving the cost and performance of CNG cylinders. A new low-cost fiber was successfully employed while the weight target was met and the cost target was missed by less than seven percent.

18 CFR 367.57 - Equipment.

Science.gov (United States)

2010-04-01

... piers and foundations that are designed to be as permanent as the buildings that house the equipment, or... walls, ceilings or floors or without in some way impairing the building, must be included in the...

Cylinder monitoring program

Energy Technology Data Exchange (ETDEWEB)

Alderson, J.H. [Martin Marietta Energy Systems, Inc., Paducah, KY (United States)

1991-12-31

Cylinders containing depleted uranium hexafluoride (UF{sub 6}) in storage at the Department of Energy (DOE) gaseous diffusion plants, managed by Martin Marietta Energy Systems, Inc., are being evaluated to determine their expected storage life. Cylinders evaluated recently have been in storage service for 30 to 40 years. In the present environment, the remaining life for these storage cylinders is estimated to be 30 years or greater. The group of cylinders involved in recent tests will continue to be monitored on a periodic basis, and other storage cylinders will be observed as on a statistical sample population. The program has been extended to all types of large capacity UF{sub 6} cylinders.

Life Prediction on a T700 Carbon Fiber Reinforced Cylinder with Limited Accelerated Life Testing Data

OpenAIRE

Ma Xiaobing; Zhang Yongbo

2015-01-01

An accelerated life testing investigation was conducted on a composite cylinder that consists of aluminum alloy and T700 carbon fiber. The ultimate failure stress predictions of cylinders were obtained by the mixing rule and verified by the blasting static pressure method. Based on the stress prediction of cylinder under working conditions, the constant stress accelerated life test of the cylinder was designed. However, the failure data cannot be sufficiently obtained by the accelerated life ...

Highly Enriched Uranium Metal Annuli and Cylinders with Polyethylene Reflectors and/or Internal Polyethylene Moderator

International Nuclear Information System (INIS)

Tyler Sumner; J. Blair Briggs; Leland Montierth

2007-01-01

for k eff . In addition to the idealizations made by the experimenters (removal of a diaphragm), a few simplifications were also made to the benchmark models that resulted in a small bias and additional uncertainty. Simplifications included omission of the support structure, possible surrounding equipment, and the walls, floor, and ceiling of the experimental cell. Bias values that result from these simplifications were determined and associated uncertainty in the bias values were included in the overall uncertainty in benchmark keff values. Bias values ranged from 0.0002 Δk to 0.0093 Δk below the experimental value. Overall uncertainties range from ± 0.0002 to ± 0.0011. Major contributors to the overall uncertainty include uncertainty in the support structure and the polyethylene parts. A comparison of experimental, benchmark-model, and MCNP-model keff values is shown in Figure 1. The experimental keff values are derived from the original reactivities reported by the principal experimentalist. The benchmark-model keff values are the experimental keff values adjusted to account for biases that were introduced by removing the support structure and surroundings. The MCNP-model keff values are simply the values found from MCNP calculations using the benchmark specifications and ENDF/B-VI cross-section data. Figure 1. Comparison of Experimental, Benchmark-Model and MCNP-Model keff value. Calculated results for most of the experiments are between 0.3-0.6% lower than the experimental values, which is consistent with fast evaluations (HEU-MET-FAST-051 and HEU-MET-FAST-071). Results for Experiments 9-13, uranium-metal cylinders reflected only on the top flat surface, range from 0.8-3.0 % low. There is an almost linear improvement in agreement with experimental values with decreasing cylindrical diameter decreased importance of axial leakage and increased importance on radial leakage

Polymeric compositions for “dry” decontamination of NPP equipment and premises

International Nuclear Information System (INIS)

Voronik, N.I.; Toropova, V.V.

2015-01-01

In JIPNR – “Sosny” NASB developed decontaminating polymeric compositions based on binder – polyvinyl alcohol solution with active additives such as nitric and borohydrofluoric acids, 1-hydroxyethylidene diphosphonic acid and its salts, detergents and fillers - natural tripoli; tripoli modified by ferrocyanides of nickel and copper; pulverized dolomite modified by manganese oxides, ferrocyanides of nickel and copper; clinoptilolite modified by iron chlorides (III) and calcium sodium phosphate and potassium ferrocyanide; hydrolytic lignin. It is shown that the developed decontaminating polymeric compositions (pastes) possess high decontaminating capacity (FD 102 – 103) and low adhesion to the surfaces of stainless and carbon steels, including painted, plastic, self-leveling floors, teflon-surface. Prolonged leaching method allowed determine the chemical resistance of “dry” decontamination wastes, strength of "1"3"7Cs and "6"0Co fixations in wastes obtained in result of using new decontamination pastes [ru

Floor interaction

DEFF Research Database (Denmark)

Petersen, Marianne Graves; Krogh, Peter; Ludvigsen, Martin

2005-01-01

Within architecture, there is a long tradition of careful design of floors. The design has been concerned with both decorating floors and designing floors to carry information. Ubiquitous computing technology offers new opportunities for designing interactive floors. This paper presents three...... different interactive floor concepts. Through an urban perspective it draws upon the experiences of floors in architecture, and provides a set of design issues for designing interactive floors....

Evolution of and projections for automated composite material placement equipment in the aerospace industry

Science.gov (United States)

McCarville, Douglas A.

2009-12-01

As the commercial aircraft industry attempts to improve airplane fuel efficiency by shifting from aluminum to composites (reinforced plastics), there is a concern that composite processing equipment is not mature enough to meet increasing demand and that delivery delays and loss of high tech jobs could result. The research questions focused on the evolution of composite placement machines, improvement of machine functionality by equipment vendors, and the probability of new inventions helping to avoid production shortfalls. An extensive review of the literature found no studies that addressed these issues. Since the early twentieth century, exploratory case study of pivotal technological advances has been an accepted means of performing historic analysis and furthering understanding of rapidly changing marketplaces and industries. This qualitative case study investigated evolution of automated placement equipment by (a) codifying and mapping patent data (e.g., claims and functionality descriptions), (b) triangulating archival data (i.e., trade literature, vender Web sites, and scholarly texts), and (c) interviewing expert witnesses. An industry-level sensitivity model developed by the author showed that expanding the vendor base and increasing the number of performance enhancing inventions will most likely allow the industry to make the transition from aluminum to composites without schedule delays. This study will promote social change by (a) advancing individual and community knowledge (e.g., teaching modules for students, practitioners, and professional society members) and (b) providing an empirical model that will help in the understanding and projection of next generation composite processing equipment demand and productivity output.

The characteristics of acoustic emission signal under composite destruction on GFRP gas cylinder

International Nuclear Information System (INIS)

Jee, Hyun Sup; Lee, Jong O; Ju, No Hoe; So, Cheal Ho; Lee, Jong Kyu

2013-01-01

This study is investigation of the characteristics for acoustic emission signal generated by destruction on glass fiber bundles and specimen that was machined composite materials surrounding the outside of GFRP cylinder. The Amplitude of acoustic emission signal gets bigger as the cutting angle of knife increases. Accordingly, the number of hits in destruction of composite materials specimen have more in longitudinal direction (longitudinal direction to the glass fiber) than in hoop direction (horizontal direction to the glass fiber) while the amplitude of signals were bigger in hoop direction than longitudinal direction. It was found out that the amplitude of the glass fiber breakage is more than 40 dB and that the amplitude of signal for matrix crack was less than 40 dB because matrix crack signal was not observed when threshold value is 40 dB and matrix crack signal suddenly appeared when threshold value is 32 dB. The slope of the amplitude is related to the acoustic emission source and the slope of the amplitude of the horizontal and vertical directions are 0.16 and 0.08. In particular, The slope of the amplitude of longitudinal direction breakage appear similar to the glass fiber breakage and therefore Acoustic emission source of longitudinal direction breakage is estimated the glass fiber breakage.

Discussion on the installation checking method of precast composite floor slab with lattice girders

Science.gov (United States)

Chen, Li; Jin, Xing; Wang, Yahui; Zhou, Hele; Gu, Jianing

2018-03-01

Based on the installation checking requirements of China’s current standards and the international norms for prefabricated structural precast components, it proposed an installation checking method for precast composite floor slab with lattice girders. By taking an equivalent composite beam consisted of a single lattice girder and the precast concrete slab as the checking object, compression instability stress of upper chords and yield stress of slab distribution reinforcement at the maximum positive moment, tensile yield stress of upper chords, slab normal section normal compression stress and shear instability stress of diagonal bars at the maximum negative moment were checked. And the bending stress and deflection of support beams, strength and compression stability bearing capacity of the vertical support, shear bearing capacity of the bolt and compression bearing capacity of steel tube wall at the bolt were checked at the same time. Every different checking object was given a specific load value and load combination. Application of installation checking method was given and testified by example.

Transient thermal stresses in composite hollow circular cylinder due to partial heat generation

International Nuclear Information System (INIS)

Goshima, Takahito; Miyao, Kaju

1979-01-01

Clad materials are adopted for the machines and structures used in contact with high temperature, corrosive atmosphere in view of their strength and economy. Large thermal stress sometimes arises in clad cylinders due to uneaven temperature field and the difference in linear thermal expansion. Vessels are often heated uneavenly, and shearing stress occurs, which is not observed in uniform heating. In this study, infinitely long, concentric cylinders of two layers were analyzed, when the internal heat changing in stepped state is generated in cylindrical form. The unsteady thermal stress occurred was determined, using thermo-elastic potential and stress functions, and assuming the thermal properties and elastic modulus of materials as constant regardless of the temperature. Laplace transformation was used, and the basic equations for thermo-elastic displacement were employed as the basis of calculation. The analysis of the temperature distribution and stress is explained. Numerical calculation was carried out on the example of an internal cylinder of SUS 304 stainless steel and an external cylinder of mild steel. The maximum shearing stress occurred in the direction of 40 deg from the heat source, and was affected largely by the position of heat generation. The effect became remarkable as time elapsed. (Kako, I.)

Evaluation of Floor Response Spectrum considering Ductility of Structure

Energy Technology Data Exchange (ETDEWEB)

Park, Junhee; Choi, In-Kil [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2014-10-15

The FRS (floor response spectrum) is directly influenced by the behavior of structure under the seismic load. If the structure is nonlinear range, the energy dissipation will be occurred by the damage of structure and the maximum force will be reduced. In Zion method, the inelastic energy abortion factor has been used to consider the nonlinearity of structure. This factor was used for the seismic fragility of structure. For the seismic fragility of equipment, the uncertainty of this factor was used differently according to the story level. But this method is not warranted under the strong earthquake leads to the structural damage. Therefore it is needed to evaluate the FRS considering the nonlinear behavior of structure and to assessment the conservatism related to nonlinear behavior of structure in FRS. In this study, the nonlinear analysis was performed for the conservatism of FRS under the damage of structure. The conservatism of FRS by the nonlinear analysis was compared by that proposed by the Zion method. The conservatism of floor acceleration response for the equipment was evaluated by performing the nonlinear analysis. From the nonlinear analysis results, it was showed that the median and β{sub c} of FRSR was increased with the ductility of structure and the response of equipment had the resonance effect between the frequency of equipment and structure. The seismic capacity of equipment by the Zion method can be different from the real seismic capacity of equipment because the inelastic structure response factor has nothing to do with the ductility of structure. Therefore the median and COV for FRSR should be defined considering the ductility of structure and the frequency of equipment for more exactly evaluating the seismic capacity of equipment.

Evaluation of Floor Response Spectrum considering Ductility of Structure

International Nuclear Information System (INIS)

Park, Junhee; Choi, In-Kil

2014-01-01

The FRS (floor response spectrum) is directly influenced by the behavior of structure under the seismic load. If the structure is nonlinear range, the energy dissipation will be occurred by the damage of structure and the maximum force will be reduced. In Zion method, the inelastic energy abortion factor has been used to consider the nonlinearity of structure. This factor was used for the seismic fragility of structure. For the seismic fragility of equipment, the uncertainty of this factor was used differently according to the story level. But this method is not warranted under the strong earthquake leads to the structural damage. Therefore it is needed to evaluate the FRS considering the nonlinear behavior of structure and to assessment the conservatism related to nonlinear behavior of structure in FRS. In this study, the nonlinear analysis was performed for the conservatism of FRS under the damage of structure. The conservatism of FRS by the nonlinear analysis was compared by that proposed by the Zion method. The conservatism of floor acceleration response for the equipment was evaluated by performing the nonlinear analysis. From the nonlinear analysis results, it was showed that the median and β c of FRSR was increased with the ductility of structure and the response of equipment had the resonance effect between the frequency of equipment and structure. The seismic capacity of equipment by the Zion method can be different from the real seismic capacity of equipment because the inelastic structure response factor has nothing to do with the ductility of structure. Therefore the median and COV for FRSR should be defined considering the ductility of structure and the frequency of equipment for more exactly evaluating the seismic capacity of equipment

Modular Flooring System

Science.gov (United States)

Thate, Robert

2012-01-01

The modular flooring system (MFS) was developed to provide a portable, modular, durable carpeting solution for NASA fs Robotics Alliance Project fs (RAP) outreach efforts. It was also designed to improve and replace a modular flooring system that was too heavy for safe use and transportation. The MFS was developed for use as the flooring for various robotics competitions that RAP utilizes to meet its mission goals. One of these competitions, the FIRST Robotics Competition (FRC), currently uses two massive rolls of broadloom carpet for the foundation of the arena in which the robots are contained during the competition. The area of the arena is approximately 30 by 72 ft (approximately 9 by 22 m). This carpet is very cumbersome and requires large-capacity vehicles, and handling equipment and personnel to transport and deploy. The broadloom carpet sustains severe abuse from the robots during a regular three-day competition, and as a result, the carpet is not used again for competition. Similarly, broadloom carpets used for trade shows at convention centers around the world are typically discarded after only one use. This innovation provides a green solution to this wasteful practice. Each of the flooring modules in the previous system weighed 44 lb (.20 kg). The improvements in the overall design of the system reduce the weight of each module by approximately 22 lb (.10 kg) (50 %), and utilize an improved "module-to-module" connection method that is superior to the previous system. The MFS comprises 4-by-4-ft (.1.2-by- 1.2-m) carpet module assemblies that utilize commercially available carpet tiles that are bonded to a lightweight substrate. The substrate surface opposite from the carpeted surface has a module-to-module connecting interface that allows for the modules to be connected, one to the other, as the modules are constructed. This connection is hidden underneath the modules, creating a smooth, co-planar flooring surface. The modules are stacked and strapped

Development of control system of coating of rod hydraulic cylinders

Science.gov (United States)

Aizhambaeva, S. Zh; Maximova, A. V.

2018-01-01

In this article, requirements to materials of hydraulic cylinders and methods of eliminating the main factors affecting the quality of the applied coatings rod hydraulic cylinders. The chromium plating process - one of ways of increase of anti-friction properties of coatings rods, stability to the wear and corrosion. The article gives description of differences of the stand-speed chromium plating process from other types of chromium plating that determines a conclusion about cutting time of chromium plating process. Conducting the analysis of technological equipment suggested addressing the modernization of high-speed chromium plating processes by automation and mechanization. Control system developed by design of schematic block diagram of a modernized and stand-speed chromium plating process.

Timber floors strengthened with concrete

NARCIS (Netherlands)

Blass, H.J.; Linden, M.L.R. van der; Schlager, M.

1998-01-01

Timber-concrete composite (tcc) beams may be used for the renovation of old timber floors. Although these systems are not new (Pokulka, 1997) and form a simple and practical solution, they are not widely adopted. One of the reasons for this is the Jack of uniform design rules. In this research

Crack resistance increasing in epoxide-rubber coatings of NPP room floors

International Nuclear Information System (INIS)

Khorenzhenko, V.I.

1986-01-01

Problems of crack resistance increasing in epoxide-rubber coatings for the floors are considered. Exploitation experience of the floors in the special rooms of NPP is given. Perspectivity of application of the compositions described as the building materials for nuclear power stations is pointed out

Perceived floor slipperiness and floor roughness in a gait experiment.

Science.gov (United States)

Yu, Ruifeng; Li, Kai Way

2015-01-01

Slips and falls contribute to occupational injuries and fatalities globally. Both floor slipperiness and floor roughness affect the occurrence of slipping and falling. Investigations on fall-related phenomena are important for the safety and health of workers. The purposes of this study were to: compare the perceived floor slipperiness before and after walking on the floor; compare the perceived floor slipperiness with and without shoes for males and females; discuss the perceived floor roughness based on barefoot walking; and establish regression models to describe the relationship between perceived floor slipperiness and actual friction of the floors. Male and female subjects walked on 3 m walkways with or without shoes. The perceived floor slipperiness ratings both before and after their walk were collected. The perceived floor slipperiness both before and after walking were significantly affected by both floor and surface conditions. Gender, floor, surface, and footwear conditions were all significant factors affecting the adjustment of perceived floor slipperiness. The subjects made more adjustment on perceived floor slipperiness rating when they had shoes on than when they were barefooted. Regression models were established to describe the relationship between perceived floor slipperiness and floor coefficient of friction. These models may be used to estimate perceived floor slipperiness, or in reverse, the coefficient of friction of the floor, so as to prevent slipping and falling in workplaces.

Mechanical Cushion Design Influence on Cylinder Dynamics

DEFF Research Database (Denmark)

Borghi, Massimo; Milani, Massimo; Conrad, Finn

2005-01-01

The paper deals with the simulation and the experimental verification of the dynamic behaviour of a linear actuator equipped with different configurations of mechanical cushion. A numerical model, developed and tailored to describe the influence of different modulation of the discharged flow....... experimental comparison, involving the piston velocity and the cylinder chambers pressure. After, with the aim of highlighting the effect of mechanical cushions design on a two effect linear actuator dynamic performances, the characteristics modulation of four alternative cushioning systems are determined...

Quantitative measurements of in-cylinder gas composition in a controlled auto-ignition combustion engine

Science.gov (United States)

Zhao, H.; Zhang, S.

2008-01-01

One of the most effective means to achieve controlled auto-ignition (CAI) combustion in a gasoline engine is by the residual gas trapping method. The amount of residual gas and mixture composition have significant effects on the subsequent combustion process and engine emissions. In order to obtain quantitative measurements of in-cylinder residual gas concentration and air/fuel ratio, a spontaneous Raman scattering (SRS) system has been developed recently. The optimized optical SRS setups are presented and discussed. The temperature effect on the SRS measurement is considered and a method has been developed to correct for the overestimated values due to the temperature effect. Simultaneous measurements of O2, H2O, CO2 and fuel were obtained throughout the intake, compression, combustion and expansion strokes. It shows that the SRS can provide valuable data on this process in a CAI combustion engine.

Quantitative measurements of in-cylinder gas composition in a controlled auto-ignition combustion engine

International Nuclear Information System (INIS)

Zhao, H; Zhang, S

2008-01-01

One of the most effective means to achieve controlled auto-ignition (CAI) combustion in a gasoline engine is by the residual gas trapping method. The amount of residual gas and mixture composition have significant effects on the subsequent combustion process and engine emissions. In order to obtain quantitative measurements of in-cylinder residual gas concentration and air/fuel ratio, a spontaneous Raman scattering (SRS) system has been developed recently. The optimized optical SRS setups are presented and discussed. The temperature effect on the SRS measurement is considered and a method has been developed to correct for the overestimated values due to the temperature effect. Simultaneous measurements of O 2 , H 2 O, CO 2 and fuel were obtained throughout the intake, compression, combustion and expansion strokes. It shows that the SRS can provide valuable data on this process in a CAI combustion engine

SU-G-206-06: Analytic Dose Function for CT Scans in Infinite Cylinders as a Function of Scan Length and Cylinder Radius

Energy Technology Data Exchange (ETDEWEB)

Bakalyar, D [Henry Ford Health System, Detroit, MI (United States); Feng, W [New York Presbyterian Hospital, Tenafly, NJ (United States); McKenney, S [Children’s National Medical Center, Washington, DC (United States)

2016-06-15

Purpose: The radiation dose absorbed at a particular radius ρ within the central plane of a long cylinder following a CT scan is a function of the length of the scan L and the cylinder radius R along with kVp and cylinder composition. An analytic function was created that that not only expresses these dependencies but is integrable in closed form over the area of the central plane. This feature facilitates explicit calculation of the planar average dose. The “approach to equilibrium” h(L) discussed in the TG111 report is seamlessly included in this function. Methods: For a cylindrically symmetric radiation field, Monte Carlo calculations were performed to compute the dose distribution to long polyethylene cylinders for scans of varying L for cylinders ranging in radius from 5 to 20 cm. The function was developed from the resultant Monte Carlo data. In addition, the function was successfully fit to data taken from measurements on the 30 cm diameter ICRU/TG200 phantom using a real-time dosimeter. Results: Symmetry and continuity dictate a local extremum at the center which is a minimum for the larger sizes. There are competing effects as the beam penetrates the cylinder from the outside: attenuation, resulting in a decrease; scatter, abruptly increasing at the circumference. This competition may result in an absolute maximum between the center and outer edge leading to a “gull wing” shape for the radial dependence. For the smallest cylinders, scatter may dominate to the extent that there is an absolute maximum at the center. Conclusion: An integrable, analytic function has been developed that provides the radial dependency of dose for the central plane of a scan of length L for cylinders of varying diameter. Equivalently, we have developed h(L,R,ρ).

The seismic response and floor spectra of OL3 NPP buildings in Finland

International Nuclear Information System (INIS)

Pentti Varpasuo

2005-01-01

The purpose of the present work is the computation of seismic response and floor spectra of the nuclear power plant OL3 buildings in Olkiluoto. The following OL3 plant buildings were included in the analysis: 1. the Reactor Building UJA/UJB; 2. the Safeguard Buildings UJH/UJK 1-4; 3. and the Fuel Building UFA The in-structure spectra were generated using the ground motion response spectra documented in YVL GUIDE 2.6 'Seismic events at nuclear power plants' issued by Finnish Centre of Radiation Protection. The floor spectra were computed for the following equipment damping values: 2%, 4%, 7%, and 10%. The joint model for the plant buildings was generated. All analyses were linear and the direct time integration method was used with time step of 0.001 sec. All response runs were carried out with MSC/Nastran general purpose structural analysis program. The development of floor spectra has been carried out in accordance with the US NRC -Regulatory Guide 1.122: 'Development of Floor Design Response Spectra for Seismic Design of Floor-Supported Equipment or Components'. The response results show that the dominant frequencies of the reactor building are located around 5 Hz in frequency space and that the typical amplification of spectral peaks for 4% damping is from 8 -10 times when compared to peak ground acceleration. (authors)

Winding of fibre composites; Vikling af fiberkompositter

Energy Technology Data Exchange (ETDEWEB)

Lystrup, Aage

2006-01-01

Within the project 'Storage of hydrogen in advanced high pressure vessels' under the PSO-R AND D 2005 program one of the tasks is to describe the technology, which is used for manufacturing of fibre reinforced pressure vessels. Fibre reinforced pressure vessels for high pressures are manufactured by winding structural load bearing fibres around a mandrel or an internal liner. There are two different types of cylindrical pressure vessels: 1) Cylinders with thick metal liner, where only the cylindrical part is over wrapped with hoop windings, and 2) cylinders with a thin metal or polymer liner, where both the cylindrical part and the end domes are over wrapped with more layers with different fibre orientations (helical and hoop windings). This report describes the fundamental principles for filament winding of fibre reinforced polymer composites. After a short introduction to the advanced fibre composites, their properties and semi-raw materials used for fibre composites, the focus is on the process parameters, which have influence on the material quality of filament wound components. The report is both covering winding of fibre reinforced thermo-setting polymers as well as thermoplastic polymers, and there are references to vendors of filament winding machines, accessory equipment and computer software for design and manufacturing of filament wound components. (au)

Pb, Nd and Sr isotopes in oceanic ferromanganese deposits and ocean floor basalts

International Nuclear Information System (INIS)

O'Nions, R.K.; Carter, S.R.; Cohen, R.S.; Evensen, N.M.; Hamilton, P.J.

1978-01-01

The Pb-, Nd-, and Sr-isotope compositions of oceanic ferromanganese deposits, together with the Nd- and Sr-isotope compositions of altered ocean-floor basalts, are here reported. These data are used to evaluate these metals as sources in both the oceans and ocean ferromanganese deposits and the extent to which ocean-floor basalts may be a source of, or a sink for, these metals. (author)

Plasmonic modes and extinction properties of a random nanocomposite cylinder

Energy Technology Data Exchange (ETDEWEB)

Moradi, Afshin, E-mail: a.moradi@kut.ac.ir [Department of Basic Sciences, Kermanshah University of Technology, Kermanshah, Iran and Department of Nano Science, Institute for Studies in Theoretical Physics and Mathematics (IPM), Tehran (Iran, Islamic Republic of)

2014-04-15

We study the properties of surface plasmon-polariton waves of a random metal-dielectric nanocomposite cylinder, consisting of bulk metal embedded with dielectric nanoparticles. We use the Maxwell-Garnett formulation to model the effective dielectric function of the composite medium and show that there exist two surface mode bands. We investigate the extinction properties of the system, and obtain the dependence of the extinction spectrum on the nanoparticles’ shape and concentration as well as the cylinder radius and the incidence angle for both TE and TM polarization.

Evaluation of high frequency ground motion effects on the seismic capacity of NPP equipments

International Nuclear Information System (INIS)

Choi, In Kil; Seo, Jeong Moon; Choun, Young Sun

2003-04-01

In this study, the uniform hazard spectrum for the example Korean nuclear power plants sites were developed and compared with various response spectra used in past seismic PRA and SMA. It shows that the high frequency ground motion effects should be considered in seismic safety evaluations. The floor response spectra were developed using the direct generation method that can develop the floor response spectra from the input response spectrum directly with only the dynamic properties of structures obtained from the design calculation. Most attachment of the equipments to the structure has a minimum distortion capacity. This makes it possible to drop the effective frequency of equipment to low frequency before it is severely damaged. The results of this study show that the high frequency ground motion effects on the floor response spectra were significant, and the effects should be considered in the SPRA and SMA for the equipments installed in a building. The high frequency ground motion effects are more important for the seismic capacity evaluation of functional failure modes. The high frequency ground motion effects on the structural failure of equipments that attached to the floor by welding can be reduced by the distortion capacity of welded anchorage

Transient Vibrations of an Elastic Cylinder Inserted in the Elastic Medium

Directory of Open Access Journals (Sweden)

Sulym Heorgij

2016-06-01

Full Text Available Using method of Laguerre polynomials we have obtained the solution of the dynamic problem of the theory of elasticity for elastic cylinder inserted into massive body modeled as a space. The source of non-stationary processes in composite is high intensity force load of the inner surface of the cylinder. On the surface separation of materials of space and cylinder the conditions of ideal mechanical contact are satisfied. The solution is obtained as series of Laguerre polynomials, which coefficients are found from recurrent relations. The results of numerical analysis of transient stress-strain state in elastic space with cylindrical insertion might be used for the technological process of hydraulic fracturing during shale gas extraction.

Prefabricated floor panels composed of fiber reinforced concrete and a steel substructure

DEFF Research Database (Denmark)

Lárusson, Lárus H.; Fischer, Gregor; Jönsson, Jeppe

2013-01-01

This paper reports on a study on prefabricated composite and modular floor deck panels composed of relatively thin fiber reinforced concrete slabs connected to steel substructures. The study focuses on the design, manufacturing, structural improvements and behavior of the floor systems during...

Engine Cylinder Temperature Control

Science.gov (United States)

Kilkenny, Jonathan Patrick; Duffy, Kevin Patrick

2005-09-27

A method and apparatus for controlling a temperature in a combustion cylinder in an internal combustion engine. The cylinder is fluidly connected to an intake manifold and an exhaust manifold. The method and apparatus includes increasing a back pressure associated with the exhaust manifold to a level sufficient to maintain a desired quantity of residual exhaust gas in the cylinder, and varying operation of an intake valve located between the intake manifold and the cylinder to an open duration sufficient to maintain a desired quantity of fresh air from the intake manifold to the cylinder, wherein controlling the quantities of residual exhaust gas and fresh air are performed to maintain the temperature in the cylinder at a desired level.

Evaluation of Flow Accelerated Corrosion of Carbon Steel with Rotating Cylinder

International Nuclear Information System (INIS)

Park, Tae Jun; Lee, Eun Hee; Kim, Kyung Mo; Kim, Hong Pyo

2012-01-01

Flow accelerated corrosion (FAC) of the carbon steel piping in nuclear power plants (NPPs) has been major issue in nuclear industry. Rotating cylinder FAC test facility was designed and fabricated and then performance of the facility was evaluated. The facility is very simple in design and economic in fabrication and can be used in material and chemistry screening test. The facility is equipped with on line monitoring of pH, conductivity, dissolved oxygen(DO), and temperature. Fluid velocity is controlled with rotating speed of the cylinder with a test specimen. FAC test of SA106 Gr. B carbon steel under 4 m/s flow velocity was performed with the rotating cylinder at DO concentration of less than 1 ppb and of 1.3 ppm. Also a corrosion test of the carbon steel at static condition, that is at zero fluid velocity, of test specimen and solution was performed at pH from 8 to 10 for comparison with the FAC data. For corrosion test in static condition, the amount of non adherent corrosion product was almost constant at pH ranging from 8 to 10. But adherent corrosion product decreased with increasing pH. This trend is consistent with decrease of Fe solubility with an increase in pH. For FAC test with rotating cylinder FAC test facility, the amount of non adherent corrosion product was also almost same for both DO concentrations. The rotating cylinder FAC test facility will be further improved by redesigning rotating cylinder and FAC specimen geometry for future work

Research on a lubricating grease print process for cylindrical cylinder

Science.gov (United States)

Yang, Liu; Zhang, Xuan; Wang, XianYan; Tan, XiaoYan

2017-09-01

In vehicle braking system and clutch system of transmission, there is always a kind of cylindrical component dose reciprocating motion. The main working method is the reciprocating motion between the rubber sealing parts and cylindrical parts, the main factor affects the service life of the product is the lubricating performance of the moving parts. So the lubricating performance between cylinders and rubber sealing rings is particularly important, same as the quality of the grease applies on the surface of the surface of cylinder. Traditional method of manually applying grease has some defects such as applying unevenly, applying tools like brush and cloth easily falls off and affect the cleanness of products, contact skin easily cause allergy, waste grease due to the uncontrollable of grease quantity using in applying, low efficiency of manual operation. An automatic, quantitative and high pressure applying equipment is introduced in this document to replace the traditional manually applying method, which can guarantee the applying quality of the grease which are painted on the surface of cylinder and bring economic benefits to the company.

Two cylinder permanent magnet stirrer for liquid metals

Science.gov (United States)

Bojarevičs, A.; Baranovskis, R.; Kaldre, I.; Milgrāvis, M.; Beinerts, T.

2017-07-01

To achieve a uniform liquid metal composition and temperature distribution, stirring is often necessary for industrial processes. Here, a novel permanent magnet system for liquid melt stirring is proposed. It promises very low energy consumption and options for multiple different flow types compared to traditional travelling magnetic field inductors or mechanical stirrers. The proposed system has a simple design: it consists of two rotating permanent magnet cylinders, which are magnetized transversely to the axis of the cylinders. The experimental device was developed and tested under various regimes using GaInSn alloy in a cylindrical crucible. Aluminum stirring by permanent magnets in laboratory scale is tested, and stirring impact on directional solidification of metallic alloys is experimentally investigated.

Internal combustion engine cylinder-to-cylinder balancing with balanced air-fuel ratios

Science.gov (United States)

Harris, Ralph E.; Bourn, Gary D.; Smalley, Anthony J.

2006-01-03

A method of balancing combustion among cylinders of an internal combustion engine. For each cylinder, a normalized peak firing pressure is calculated as the ratio of its peak firing pressure to its combustion pressure. Each cylinder's normalized peak firing pressure is compared to a target value for normalized peak firing pressure. The fuel flow is adjusted to any cylinder whose normalized peak firing pressure is not substantially equal to the target value.

Relationship of pressure to temperature rise in overfilled cylinders

International Nuclear Information System (INIS)

Barber, E.J.

1979-01-01

Mild steel pressure vessels containing uranium hexafluoride are heated in 96-inch diameter autoclaves to allow the feed material to enter the gaseous diffusion process equipment for enrichment in the uranium 235 isotope. For purposes of safety analysis it is necessary to establish the ability of the instrumentation to shut off the steam supply to the autoclave prior to cylinder rupture if the cylinder has been overfilled. To make this determination requires estimates of the rate of change of pressure with respect to change of temperature at constant volume as a function of the temperature at which the ullage disappears. The paper presents the calculations for the estimation of this rate of change for liquid uranium hexafluoride using the ratio of the coefficients of expansion and compressibility using empirical liquid density data and the Eyring equation of state for liquids. 5 figs. (MB)

Performance of a Horizontal Triple Cylinder Type Pulping Machine

Directory of Open Access Journals (Sweden)

Sukrisno Widyotomo

2011-05-01

Full Text Available Pulping is one important step in wet coffee processing method. Pulping process usually uses a machine which constructed by wood or metal materials. A horizontal single cylinder type of fresh coffee cherries pulping machine is the most popular machine in coffee processing. One of the weaknesses of a horizontal single cylinder type of fresh coffee cherries pulping machine is higher in broken beans. Broken bean is one of mayor aspects in defect system that contribute to low quality. Indonesian Coffee and Cocoa Research Institute has designed and tested a horizontal double cylinder type of fresh coffee cherries pulping machine which resulted in 12.6—21.4% of broken beans. To reduce percentage of broken beans, Indonesian Coffee and Cocoa Research Institute has developed and tested a horizontal triple cylinder type of fresh coffee cherries pulping machine. Material tested was fresh mature Robusta coffee cherries, 60—65% (wet basis moisture content; has classified on 3 levels i.e. unsorted, small and medium, and clean from metal and foreign materials. The result showed that the machine produced 6,340 kg/h in optimal capacity for operational conditions, 1400 rpm rotor rotation speed for unsorted coffee cherries with composition 55.5% whole parchment coffee, 3.66% broken beans, and 1% beans in wet skin.Key words : coffee, pulp, pulper, cylinder, quality.

Design and Manufacturing of Composite Tower Structure for Wind Turbine Equipment

Science.gov (United States)

Park, Hyunbum

2018-02-01

This study proposes the composite tower design process for large wind turbine equipment. In this work, structural design of tower and analysis using finite element method was performed. After structural design, prototype blade manufacturing and test was performed. The used material is a glass fiber and epoxy resin composite. And also, sand was used in the middle part. The optimized structural design and analysis was performed. The parameter for optimized structural design is weight reduction and safety of structure. Finally, structure of tower will be confirmed by structural test.

Nanosilica reinforced epoxy floor coating composites: preparation and thermophysical characterization

Directory of Open Access Journals (Sweden)

Mir Mohammad Alavi Nikje

2012-01-01

Full Text Available In this study, flooring grade epoxy/nanoSiO2 nanocomposites were prepared by in-situ polymerization method. Nano silica was treated by coupling agent in order to surface treating and introducing of reactive functional groups to achieving adequate bonding between polar inorganic nano particles and epoxy organic polymer. γ-Aminopropyltriethoxysilane (Amino A-100 was used as an effective and commercially available coupling agent and nano silica treated in acetone media. SEM observations of cured samples revealed that the nano silica was completely dispersed into polymer matrix into nanoscale particles. Thermal and physical properties of prepared samples were investigated and data showed improvements in physical and mechanical properties of the flooring samples in comparison with unfilled resin.

Load-cell-based weighing system for weighing 9.1- and 12.7-tonne UF6 cylinders

International Nuclear Information System (INIS)

McAuley, W.A.; Kane, W.R.

1986-01-01

For the independent verification of UF 6 cylinder masses by the International Atomic Energy Agency (IAEA) at uranium enrichment facilities, an 18-tonne capacity Load-Cell-Based Weighing System (LCBWS) has been developed. The system was developed at Brookhaven National Laboratory and the Oak Ridge Gaseous Diffusion Plant and calibrated at the US National Bureau of Standards. The principal components of the LCBWS are two load cells, with readout and ancillary equipment, and a lifting fixture that couples the load cells to a cylinder. Initial experience with the system demonstrates that it has the advantages of transportability, ease of application, stability, and an attainable accuracy of 2 kg or better for a full cylinder

Simplified static method for determining seismic loads on equipment in moderate and high hazard facilities

International Nuclear Information System (INIS)

Scott, M.A.; Holmes, P.A.

1991-01-01

A simplified static analysis methodology is presented for qualifying equipment in moderate and high-hazard facility-use category structures, where the facility use is defined in Design and Evaluation Guidelines for Department of Energy Facilities Subjected to Natural Phenomena Hazards, UCRL-15910. Currently there are no equivalent simplified static methods for determining seismic loads on equipment in these facility use categories without completing dynamic analysis of the facility to obtain local floor accelerations or spectra. The requirements of UCRL-15910 specify the use of open-quotes dynamicclose quotes analysis methods, consistent with Seismic Design Guidelines for Essential Buildings, Chapter 6, open-quotes Nonstructural Elements,close quotes TM5-809-10-1, be used for determining seismic loads on mechanical equipment and components. Chapter 6 assumes that the dynamic analysis of the facility has generated either floor response spectra or model floor accelerations. These in turn are utilized with the dynamic modification factor and the actual demand and capacity ratios to determine equipment loading. This complex methodology may be necessary to determine more exacting loads for hard to qualify equipment but does not provide a simple conservative loading methodology for equipment with ample structural capacity

State-of-the-art of development of floor spectra

International Nuclear Information System (INIS)

Singh, M.P.

1984-01-01

Floor spectra are used as seismic inputs for the design and qualification of subsystems and equipment. Until very recently, the time history analyses with single acceleration time history as input were very commonly used. However, this approach has been observed to give nonunique floor spectrum curves. Thus, as alternatives several direct approaches have been developed. The approaches which are based on the random vibration principles but employ response spectra directly have more rational appeal. Several such approaches are available. Four different approaches, employing the mode displacement and mode acceleration formulations, covering the proportionally as well as nonproportionally damped structures, are presented. The mode displacement formulations are most commonly used, although the mode acceleration formulations seem to be the better alternatives, both for the proportionally and nonproportionally damped structures. The need for the development of other forms of floor response spectra such as the relative velocity and relative acceleration spectra is also identified

Investigation of the rolling motion of a hollow cylinder using a smartphone

Science.gov (United States)

Puttharugsa, Chokchai; Khemmani, Supitch; Utayarat, Patipan; Luangtip, Wasutep

2016-09-01

This paper describes the use of smartphone’s gyroscope sensor to analyse a hollow cylinder rolling down an inclined plane. The smartphone (iPhone 4s) was attached to the end of hollow cylinder and was equipped with the Sensorlog application (Sensorlog app) to record the angular speed of rolling down an inclined plane. The experimental results agree with the theoretical model that is familiar to students for the rolling motion on an inclined plane. Moreover, the coefficients of static friction and kinetic friction were determined to be 0.205 ± 0.011 and 0.178 ± 0.003 from the measurements, respectively. This experiment demonstrated an alternative way to teach the rolling motion in a physics laboratory.

Spark ignition engine control: estimation and prediction of the in-cylinder mass and chemical species; Controle moteur a allumage commande: estimation / prediction de la masse et de la composition du melange enferme dans le cylindre

Energy Technology Data Exchange (ETDEWEB)

Giansetti, P.

2005-09-15

Spark ignition engine control has become a major issue regarding compliance with emissions legislation while ensuring driving comfort. The objective of this thesis was to estimate the mass and composition of gases inside the cylinder of an engine based on physics in order to insure better control of transient phases taking into account residual gases as well as exhaust gas recirculation. Residual gas fraction has been characterized using two experiments and one CFD code. A model has been validated experimentally and integrated into an observer which predicts pressure and temperature inside the manifold. The predictions of the different gas flows and the chemical species inside the cylinder are deduced. A closed loop observer has been validated experimentally and in simulation. Moreover, an algorithm estimating the fresh and burned gas mass from the cylinder pressure has been proposed in order to obtain the information cycle by cycle and cylinder by cylinder. (author)

An experimental study on thermal properties of composite insulation

Energy Technology Data Exchange (ETDEWEB)

Choi, Gyoung-Seok [Building and Urban Research Department, Korea Institute of Construction Technology, 2311 Daehwa-Dong, Ilsanseo-Gu, Goyang-Si, Gyeonggi-Do 411-712 (Korea); College of Architecture, Hanyang University, 17, Hangdang-Dong, Sungdong-Gu, Seoul 133-791 (Korea); Kang, Jae-Sik; Jeong, Young-Sun; Lee, Seung-Eon [Building and Urban Research Department, Korea Institute of Construction Technology, 2311 Daehwa-Dong, Ilsanseo-Gu, Goyang-Si, Gyeonggi-Do 411-712 (Korea); Sohn, Jang-Yeul [College of Architecture, Hanyang University, 17, Hangdang-Dong, Sungdong-Gu, Seoul 133-791 (Korea)

2007-04-01

In accordance with the insulation standards reinforced since 2001 and the compulsory standards on floor impact sound insulation that have been enforced since 2004, insulation materials for actual buildings have been converted to composite materials and new insulation materials have been released in the market. However, Korea is lagging behind the world in fundamental experimental studies and resources. In case of some composite insulation materials, there also have been problems of distorted performance occurring as a result of tests being conducted without having verification and evaluation on the accuracy and inaccuracy of such tests. Therefore, this study grasped the thermal properties of composite insulation materials using thermal conductivity test equipment by heat flux method, and performed quantitative evaluation on the measurement precision and uncertainty of composite materials. (author)

Performance Evaluation of Rotating Cylinder Type Coffee Bean Roaster

Directory of Open Access Journals (Sweden)

Sutarsi

2010-04-01

Full Text Available One strategy attempts to reduce dependence on primary commodity markets are overseas market expansion and development of secondary products. In the secondary product processing coffee beans is required of supporting equipment to facilitate these efforts. Research Center for Indonesian Coffee and Cocoa has developed coffee bean roaster. However, there are still many people who do not know about the technical aspects of roaster machine type of rotating cylinder so that more people use traditional ways to roast coffee beans. In order for the benefits of this machine is better known society it is necessary to study on the technical aspects. The purpose of this research is to evaluate the technical performance of the coffee beans roaster machine type of rotating cylinder. These include the technical aspects of work capacity of the machine, roasting technical efficiency, fuel requirements, and power requirements of using roaster machine. Research methods are including data collection, calculation and analysis. The results showed that the roaster machine type of a rotating cylinder has capacity of 12.3 kg/hour. Roasting efficiency is 80%. Fuel consumption is 0.6 kg. The calculated amount of the used power of current measurement is the average of 0.616 kW.

Fabrication of patient specific composite orbital floor implants by stereolithography

NARCIS (Netherlands)

Geven, Mike A.; Varjas, Viktor; Kamer, Lukas; Wang, Xinjiang; Peng, Jiang; Eglin, David; Grijpma, Dirk W.

2015-01-01

Fractures of the orbital floor are common in traffic accidents and assaults, and inadequate treatment can result in serious complications. Accurate anatomical reconstruction of the orbit using implants is the preferred treatment. Implants require degradability, adequate mechanical properties to

Gas Cylinder Safety, Course 9518

Energy Technology Data Exchange (ETDEWEB)

Glass, George [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

2016-10-27

This course, Gas Cylinder Safety (#9518), presents an overview of the hazards and controls associated with handling, storing, using, and transporting gas cylinders. Standard components and markings of gas cylinders are also presented, as well as the process for the procurement, delivery, and return of gas cylinders at Los Alamos National Laboratory (LANL).

Nuclear criticality safety evaluation of large cylinder cleaning operations in X-705, Portsmouth Gaseous diffusion Plant

International Nuclear Information System (INIS)

Sheaffer, M.K.; Keeton, S.C.; Lutz, H.F.

1995-06-01

This report evaluates nuclear criticality safety for large cylinder cleaning operations in the Decontamination and Recovery Facility, X-705, at the Portsmouth Gaseous Diffusion Plant. A general description of current cleaning procedures and required hardware/equipment is presented, and documentation for large cylinder cleaning operations is identified and described. Control parameters, design features, administrative controls, and safety systems relevant to nuclear criticality are discussed individually, followed by an overall assessment based on the Double Contingency Principle. Recommendations for enhanced safety are suggested, and issues for increased efficiency are presented

Evaluation of non destructive testing to characterize the resistance of the prefabricated system of columns and floor tiles for single family homes of a level: permeability meter, determination of wave velocity by ultrasound, Schmidt sclerometer and metal detector

International Nuclear Information System (INIS)

Quesada Chacon, Dannell

2014-01-01

Non destructive testing are determined to be correlated with resistance to compression and flexion of elements belonging to prefabricated system of columns and floor tiles for single family homes of a level. The characteristics of the non destructive testing are described, such as: measurer of permeability, Schmidt sclerometer, determination of wave velocity by ultrasound and metal detector. The columns and floor tiles are elaborated with 2 mixtures of different resistances at 28 days. The first more than 30 MPa and the second less than 25 MPa are sampled together with the control cylinders necessary to obtain the actual resistance according to ASTM C39. Last resistance testings to compression and Schmidt sclerometer are realized to control cylinders to 1, 2, and 4 weeks after being cast. Non destructive testings (permeability meter Torrent, Schmidt sclerometer and determination of wave velocity by ultrasound) are performed in columns and floor tiles to 1, 2, and 4 weeks after being cast. Last resistance testings to flexion is obtained by means of destructive tests of the columns and floor tiles sampled. The correlation of the data obtained is determined to derive values of compression resistance from non destructive testing [es

Development of bonded composite doublers for the repair of oil recovery equipment.

Energy Technology Data Exchange (ETDEWEB)

Roach, David W.; Rackow, Kirk A.

2005-06-01

An unavoidable by-product of a metallic structure's use is the appearance of crack and corrosion flaws. Economic barriers to the replacement of these structures have created an aging infrastructure and placed even greater demands on efficient and safe repair methods. In the past decade, an advanced composite repair technology has made great strides in commercial aviation use. Extensive testing and analysis, through joint programs between the Sandia Labs FAA Airworthiness Assurance Center and the aviation industry, have proven that composite materials can be used to repair damaged aluminum structure. Successful pilot programs have produced flight performance history to establish the durability of bonded composite patches as a permanent repair on commercial aircraft structures. With this foundation in place, this effort is adapting bonded composite repair technology to civil structures. The use of bonded composite doublers has the potential to correct the difficulties associated with current repair techniques and the ability to be applied where there are no rehabilitation options. It promises to be cost-effective with minimal disruption to the users of the structure. This report concludes a study into the application of composite patches on thick steel structures typically used in mining operations. Extreme fatigue, temperature, erosive, and corrosive environments induce an array of equipment damage. The current weld repair techniques for these structures provide a fatigue life that is inferior to that of the original plate. Subsequent cracking must be revisited on a regular basis. The use of composite doublers, which do not have brittle fracture problems such as those inherent in welds, can help extend the structure's fatigue life and reduce the equipment downtime. Two of the main issues for adapting aircraft composite repairs to civil applications are developing an installation technique for carbon steel and accommodating large repairs on extremely thick

Fiber Tracking Cylinder Nesting

International Nuclear Information System (INIS)

Stredde, H.

1999-01-01

The fiber tracker consists of 8 concentric carbon fiber cylinders of varying diameters, from 399mm to 1032.2mm and two different lengths. 1.66 and 2.52 meters. Each completed cylinder is covered over the entire o.d. with scintillating fiber ribbons with a connector on each ribbon. These ribbons are axial (parallel to the beam line) at one end and stereo (at 3 deg. to the beam line) at the other. The ribbon connectors have dowel pins which are used to match with the connectors on the wave guide ribbons. These dowel pins are also used during the nesting operation, locating and positioning measurements. The nesting operation is the insertion of one cylinder into another, aligning them with one another and fastening them together into a homogeneous assembly. For ease of assembly. the nesting operation is accomplished working from largest diameter to smallest. Although the completed assembly of all 8 cylinders glued and bolted together is very stiff. individual cylinders are relatively flexible. Therefore. during this operation, No.8 must be supported in a manner which maintains its integrity and yet allows the insertion of No.7. This is accomplished by essentially building a set of dummy end plates which replicate a No.9 cylinder. These end plates are mounted on a wheeled cart that becomes the nesting cart. Provisions for a protective cover fastened to these rings has been made and will be incorporated in finished product. These covers can be easily removed for access to No.8 and/or the connection of No.8 to No.9. Another wheeled cart, transfer cart, is used to push a completed cylinder into the cylinder(s) already mounted in the nesting cart.

Transient thermal stresses in a transversely isotropic finite composite hollow circular cylinder due to arbitrary surface heat-generations and surrounding temperatures

International Nuclear Information System (INIS)

Sugano, Y.

1981-01-01

An exact solution is given for the temperature distribution, the thermal stresses and displacements in a transversely isotropic finite composite hollow circular cylinder composed of two distinct cylindrical laminae. The temperature field is determined by using of the Laplace transform and the finite Fourier-cosine transform, respectively, with respect to time and axial coordinate included in the governing equation and the associated thermal stresses and displacements are analvsed by the use of a set of stress functions closely related to the Love's function valid for the axisymmetric isothermal problem of isotropic bodies. (orig.)

Initial decontamination of the equipment decontamination room at the West Valley Demonstration Project. Topical report, September 1983-May 1985

International Nuclear Information System (INIS)

Meigs, R.A.

1985-12-01

The purpose of this report is to document the initial decontamination of the Equipment Decontamination Room (EDR). The effort spanned a two-year period and included packaging and removal of waste; grinding away contaminated concrete floors; pump-out and spraydown of an equipment soaking pit; washing and painting of walls, equipment, and floors; refurbishment of utilities and various pieces of equipment; and load tests of EDR and Chemical Process Cell (CPC) cranes. After decontamination, the EDR was converted into a waste handling area for the decommissioning of the CPC

SUSTAINABLE TRAILER FLOORING

Directory of Open Access Journals (Sweden)

John Lu

2009-05-01

Full Text Available Different trailer flooring materials, including wood-based, aluminum, steel, and synthetic plastic floors, were evaluated in accordance with their durability and sustainability to our natural environment. Wood-based trailer flooring is an eco-friendly product. It is the most sustainable trailer flooring material compared with fossil fuel-intensive steel, aluminum, and plastics. It is renewable and recyclable. Oak, hard maple, and apitong are strong and durable hardwood species that are currently extensively used for trailer flooring. For manufacture, wood-based flooring is higher in energy efficiency and lower in carbon emission than steel, aluminum and plastics. Moreover, wood per se is a natural product that sequesters carbon. Accordingly, using more wood-based trailer flooring is effective to reduce global warming.

Peak-Broadening of Floor Response Spectra for Base Isolated Nuclear Structures

International Nuclear Information System (INIS)

Ju, Heekun; Choun, Young-Sun; Kim, Min-Kyu

2015-01-01

In this paper, uncertainties in developing FRS are explained first. Then FDRS of a fixed structure is computed using a conventional method as an example. Lastly FRS of a base-isolated structure is computed and suitability of current peak-broadening method is examined. Uncertainties in the material property of structure influence FRS of fixed structures significantly, but their effect on FRS of base-isolated structures is negligible. Nuclear structures should be designed to ensure the safety of equipment and components mounted on their floors. However, coupled analysis of a structure and components is complex, so equipment is separately analyzed using floor response spectra (FRS). FRS calculated from dynamic analysis of structural model should be modified to create floor design response spectra (FDRS), the input for seismic design of equipment. For nuclear structures, smoothing and broadening peaks of FRS is required to account for uncertainties owing to material properties of structures, soil, modeling techniques, and others. The peak broadening method proposed for fixed based structures may not be appropriate for base-isolated structures because of additional uncertainties in the property of isolation bearings. For base-isolated structures, mechanical property of isolator plays a dominant role on the change of FRS. As base-isolated nuclear plants should meet the ASCE provisions, uncertainty in the isolation system would be around 10%. For the base isolated 3-storied beam model with 2.5-sec isolation period, 6.9% of broadening ratio was enough for development of FDRS at the required variation condition. Also for the models with various isolation periods, less than 10% of broadening ratio was sufficient

Performance of a Horizontal Double Cylinder Type of Fresh Coffee Cherries Pulping Machine

Directory of Open Access Journals (Sweden)

Sukrisno Widyotomo

2009-05-01

Full Text Available Pulping is one important step in wet coffee processing method. Usually, pulping process uses a machine which constructed using wood or metal materials. A horizontal single cylinder type coffee pulping machine is the most popular machine in coffee processor and market. One of the weakness of a horizontal single cylinder type coffee pulping machine is high of broken beans. Broken beans is one of major aspect in defect system that result in low quality. Indonesian Coffee and Cocoa Research Institute has designed and tested a horizontal double cylinder type coffee pulping machine. Material tested is Robusta cherry, mature, 60—65% (wet basis moisture content, which size compostition of coffee cherries was 50.8% more than 15 mm diameter, 32% more than 10 mm diameter, and 16.6% to get through 10 mm hole diameter; 690—695 kg/m3 bulk density, and clean from methal and foreign materials. The result showed that this machine has 420 kg/h optimal capacity in operational conditions, 1400 rpm rotor rotation speed for unsorted coffee cherries with composition 53.08% whole parchment coffee, 16.92% broken beans, and 30% beans in the wet skin. For small size coffee cherries, 603 kg/h optimal capacity in operational conditions, 1600 rpm rotor rotation speed with composition 51.30% whole parchment coffee, 12.59% broken beans, and 36.1% beans in the wet skin. Finally, for medium size coffee cherries, 564 kg/h optimal capacity in operational conditions, 1800 rpm rotor rotation speed with composition 48.64% whole parchment coffee, 18.5% broken beans, and 32.86% beans in the wet skin.Key words : coffee, pulp, pulper, cylinder, quality.

Influence of soil-structure interaction on floor response spectra

International Nuclear Information System (INIS)

Costantino, C.J.; Miller, C.A.; Curreri, J.R.

1985-01-01

A study was undertaken to investigate the influence of soil-structure interaction on floor response spectra developed in typical nuclear power plant structures. A horizontal earthquake time history, whose spectra envelops the Regulatory Guide 1.60 criteria and is scaled to a log peak acceleration, was used as input to structural models. Two different structural stick models were used, representing typical BWR and PWR facilities. By varying the structural and soil stiffness parameters, a wide range of system behaviors were investigated. Floor response spectra, required to assess equipment qualification, were of primary interest. It was found from a variation of parameter study that the interaction soil parameters, particularly radiation damping, greatly affect the nature of the calculated responses. 2 refs., 2 figs., 2 tabs

Influence of soil-structure interaction on floor response spectra

International Nuclear Information System (INIS)

Costantino, C.J.; Miller, C.A.; Curreri, J.R.

1985-01-01

A study was undertaken to investigate the influence of soil-structure interaction on floor response spectra developed in typical nuclear power plant structures. A horizontal earthquake time history, whose spectra envelops the Reg. Guide 1.60 criteria and is scaled to a 1 g peak acceleration, was used as input to structural models. Two different structural stick models were used, representing typical BWR and PWR facilities. By varying the structural and soil stiffness parameters, a wide range of system behaviors were investigated. Floor response spectra, required to assess equipment qualification, were of primary interest. It was found from a variation of parameter study that the interaction soil parameters, particularly radiation damping, greatly affect the nature of the calculated responses. (orig.)

Antennas on circular cylinders

DEFF Research Database (Denmark)

Knudsen, H. L.

1959-01-01

On the basis of the results obtained by Silver and Saunders [4] for the field radiated from an arbitrary slot in a perfectly conducting circular cylinder, expressions have been derived for the field radiated by a narrow helical slot, with an arbitrary aperture field distribution, in a circular...... antenna in a circular cylinder. By a procedure similar to the one used by Silver and Saunders, expressions have been derived for the field radiated from an arbitrary surface current distribution on a cylinder surface coaxial with a perfectly conducting cylinder. The cases where the space between the two...

Hot conditioning equipment conceptual design report

International Nuclear Information System (INIS)

Bradshaw, F.W.

1996-01-01

This report documents the conceptual design of the Hot Conditioning System Equipment. The Hot conditioning System will consist of two separate designs: the Hot Conditioning System Equipment; and the Hot Conditioning System Annex. The Hot Conditioning System Equipment Design includes the equipment such as ovens, vacuum pumps, inert gas delivery systems, etc.necessary to condition spent nuclear fuel currently in storage in the K Basins of the Hanford Site. The Hot Conditioning System Annex consists of the facility of house the Hot Conditioning System. The Hot Conditioning System will be housed in an annex to the Canister Storage Building. The Hot Conditioning System will consist of pits in the floor which contain ovens in which the spent nuclear will be conditioned prior to interim storage

Hot conditioning equipment conceptual design report

Energy Technology Data Exchange (ETDEWEB)

Bradshaw, F.W., Westinghouse Hanford

1996-08-06

This report documents the conceptual design of the Hot Conditioning System Equipment. The Hot conditioning System will consist of two separate designs: the Hot Conditioning System Equipment; and the Hot Conditioning System Annex. The Hot Conditioning System Equipment Design includes the equipment such as ovens, vacuum pumps, inert gas delivery systems, etc.necessary to condition spent nuclear fuel currently in storage in the K Basins of the Hanford Site. The Hot Conditioning System Annex consists of the facility of house the Hot Conditioning System. The Hot Conditioning System will be housed in an annex to the Canister Storage Building. The Hot Conditioning System will consist of pits in the floor which contain ovens in which the spent nuclear will be conditioned prior to interim storage.

Wake flow behaviour behind a smaller cylinder oscillating in the wake of an upstream stationary cylinder

Energy Technology Data Exchange (ETDEWEB)

Gao, Yangyang; Sun, Zhilin [Ocean College, Zhejiang University, Hangzhou 310058 (China); Tan, Danielle S [Maritime Research Centre, Nanyang Technological University, Singapore 639798 (Singapore); Yu, Dingyong [College of Engineering, Ocean University of China, 266100 (China); Tan, Soon Keat, E-mail: yygao@zju.edu.cn [Nanyang Environment and Water Research Institute, Nanyang Technological University, Singapore 639798 (Singapore)

2014-04-01

The flow patterns around a cylinder oscillating freely in the wake of a larger cylinder upstream were investigated using the particle image velocimetry technique. The upstream cylinder was fixed at both ends while the downstream smaller cylinder was held by springs such that it was free to oscillate in the transverse direction. The flow patterns, amplitudes of oscillation and vortex shedding frequencies were compared with those of a single cylinder. In the presence of the upstream cylinder, the three parameters characterizing the oscillation response of the smaller cylinder—amplitude of oscillation, vortex shedding frequency and Reynolds stresses—were greatly reduced. While their magnitude increased with gap ratio, these three parameters were still smaller than the corresponding magnitudes for a single oscillating cylinder. The peak values of turbulence statistics such as Reynolds shear stress and normal stress behind the oscillating downstream cylinder were similarly reduced, and increased with gap ratios. (paper)

Low-Impact Flooring: Does It Reduce Fall-Related Injuries?

Science.gov (United States)

Hanger, H Carl

2017-07-01

To compare fall rates and injuries from falls on low-impact flooring (LIF) compared with a standard vinyl flooring. Prospective, observational, nonrandomized controlled study. Subacute Older Persons Health ward (N = 20 beds). Older inpatients. Three different types of LIF. All falls in the ward were prospectively monitored using incident reporting, noting location and consequences of each fall. Fall rates (per 1000 bed days) and injuries, were compared between bedroom falls on LIF against those occurring on standard vinyl flooring (controls). Over 31 months, there were 278 bedroom falls (from 178 fallers). The bedroom fall rate (falls per 1000 bed days occupied) did not differ between the LIF and control groups (median 15 [IQR 8-18] versus 17 [IQR 9-23], respectively; P = .47). However, fall-related injuries were significantly less frequent when they occurred on LIFs (22% of falls versus 34% of falls on control flooring; P = .02). Fractures occurred in 0.7% of falls in the LIF cohort versus 2.3% in the control cohort. Rolling resistance when moving heavier equipment, such as beds or hoists, was an issue for staff on LIF. LIF significantly reduced fall-related injuries compared with a standard vinyl flooring, whereas they did not alter the overall risk of falling. Copyright © 2017 AMDA – The Society for Post-Acute and Long-Term Care Medicine. Published by Elsevier Inc. All rights reserved.

Floors: Selection and Maintenance.

Science.gov (United States)

Berkeley, Bernard

Flooring for institutional, commercial, and industrial use is described with regard to its selection, care, and maintenance. The following flooring and subflooring material categories are discussed--(1) resilient floor coverings, (2) carpeting, (3) masonry floors, (4) wood floors, and (5) "formed-in-place floors". The properties, problems,…

Self adaptive internal combustion engine control for hydrogen mixtures using piezoelectric transducers for dynamic cylinder pressure monitoring

Energy Technology Data Exchange (ETDEWEB)

Courteau, R.; Bose, T.K. [Quebec Univ., Trois-Rivieres, PQ (Canada). Institut de recherche sur l' hydrogene

2004-07-01

Hydrogen internal combustion engine research at the Hydrogen Research Institute includes the following infrastructure: a 20 square metre test cell, an engine preparation room, a 150 hp dynamometer, exhaust gas analysers and a hydrogen supply. The goal of the research is to develop internal combustion engine technologies that can use hydrogen as a fuel without knocking, backfires, excessive engine wear, and with low emissions. As well as hydrogen, fuels such as biogas are also investigated. Technologies under investigation include adaptive control algorithms, as well as advanced sensors and actuators. The latter include piezolelectrics, optical fibres, nitrogen oxide detectors, and chemical composition detectors. Developments include microprocessor-controlled injection and ignition control systems for both single cylinder and multicylinder engines. Research on the influence of fuel composition on best ignition timing is presented. There is also dynamic cylinder pressure monitoring to prevent knocking make engine state assessments and perform engine calibration. Piezoelectric cylinder pressure sensors are employed, either integrated with the spark plugs, or stand-alone, inserted through separate holes through the cylinder head. tabs, figs.

Large-component handling equipment and its use

International Nuclear Information System (INIS)

Krieg, S.A.; Swannack, D.L.

1983-01-01

The Fast Flux Test Facility (FFTF) reactor systems have special requirements for component replacements during maintenance servicing. Replacement operations must address handling of equipment within shielded metal containers while maintaining an inert atmosphere to prevent reaction of sodium with air. Plant identification of a failed component results in selecting and assembling the maintenance cask and equipment transport system for transfer from the storage facility to the Reactor Containment Building (RCB). This includes a proper diameter and length cask, inert atmosphere control consoles, component lift fixture and support structure for interface with the facility area surrounding the component. This equipment is staged in modular groups in the Reactor Service Building for transfer through the equipment airlock to the containment interior. The failed component is generally prepared for replacement by installation of the special lifting fixture attachment. Assembly of the cask support structure is performed over the component position on the containment building operating floor. The cask and shroud from the reactor interface are inerted after all manual service connections and handling attachments are completed. The component is lifted from the reactor and into the cask interior through a floor valve which is then closed to isolate the component reactor port. The cask with sodium wetted component is transferred to a service/repair location, either within containment or outside, to the Maintenance Facility cleaning and repair area. The complete equipment and handling operations for replacement of a large reactor component are described

Analysis of causes of combustible mixture explosions inside production floor areas

Directory of Open Access Journals (Sweden)

Lyapin Anton

2016-01-01

Full Text Available The work provides a cause analysis for major industrial explosions and a review of the causes of combustive air-gas mixture generation in a production environment. It has been established that during operation of explosive production facilities, it is process equipment that, as a rule, creates explosive environment inside the floor area. A qualitative method for determination of a potential accident has been reviewed. Analysis of the nature of explosion effect on building structures and equipment has shown that exposions characterised by absence of equipment and building structure disintegration normally have a localized character. It has been identified that during explosions inside process equipment, the largest structural damage occurs in spots hit by equipment debris. Complete destruction of building structures and equipment is caused by explosions inside equipment containing large quantities of combustible products. It has been identified that most explosions are accompanied by partial or total destruction of building structures and equipment. Therefore, measures taken to protect equipment and buildings from explosion effects lack efficiency.

Axisymmetric Vibration of Piezo-Lemv Composite Hollow Multilayer Cylinder

Directory of Open Access Journals (Sweden)

E. S. Nehru

2012-01-01

Full Text Available Axisymmetric vibration of an infinite piezolaminated multilayer hollow cylinder made of piezoelectric layers of 6 mm class and an isotropic LEMV (Linear Elastic Materials with Voids layers is studied. The frequency equations are obtained for the traction free outer surface with continuity conditions at the interfaces. Numerical results are carried out for the inner, middle, and outer hollow piezoelectric layers bonded by LEMV (It is hypothetical material layers and the dispersion curves are compared with that of a similar 3-layer model and of 3 and 5 layer models with inner, middle, and outer hollow piezoelectric layers bonded by CFRP (Carbon fiber reinforced plastics.

Development of remote operated floor contamination monitor

International Nuclear Information System (INIS)

Sreekumar, K.; Gangamohan, M.; Kannan, R.K.; Rajan, S.

2005-01-01

Contamination check of floors and walkways in and around Reactor building areas forms an integral part of Radiation Protection Program in Power Stations. Though random swipe check method is adopted for the detection of loose contamination, this method has the disadvantage of leaving the fixed contamination and hotspots undetected. Hence, scanning the area with a sensitive detector, held close to the surface provides positive means for the detection of contamination. Checking large areas and walkways by holding the detector close to the surface involves physical work. Also, areas which are unapproachable due to congestion of equipment, may go uncovered by contamination monitoring in order to eliminate the physical strain involved in such contamination monitoring and to cover unapproachable areas, a small size prototype device that can be operated remotely was fabricated. This device detects contamination instantaneously and accurately. This paper describes design and fabrication of the device used for floor contamination monitoring. (author)

Sonar discrimination of cylinders from different angles using neural networks neural networks

DEFF Research Database (Denmark)

Andersen, Lars Nonboe; Au, Whiwlow; Larsen, Jan

1999-01-01

This paper describes an underwater object discrimination system applied to recognize cylinders of various compositions from different angles. The system is based on a new combination of simulated dolphin clicks, simulated auditory filters and artificial neural networks. The model demonstrates its...

Effect of longitudinal and transverse vibrations of an upstream square cylinder on vortex shedding behind two inline square cylinders

International Nuclear Information System (INIS)

Patil, Pratish P; Tiwari, Shaligram

2009-01-01

The characteristics of unsteady wakes behind a stationary square cylinder and another upstream vibrating square cylinder have been investigated numerically with the help of a developed computational code. The effect of longitudinal as well as transverse vibrations of the upstream cylinder is studied on the coupled wake between the two cylinders, which is found to control the vortex shedding behavior behind the downstream stationary cylinder. Computations are carried out for a fixed value of Reynolds number (Re = 200) and three different values of excitation frequencies of the upstream cylinder, namely less than, equal to and greater than the natural frequency of vortex shedding corresponding to flow past a stationary square cylinder. The vortex shedding characteristics of the unsteady wakes behind the vibrating and stationary cylinders are found to differ significantly for longitudinal and transverse modes of vibration of the upstream cylinder. The wake of the downstream stationary cylinder is found to depict a synchronization behavior with the upstream cylinder vibration. The spacing between the two cylinders has been identified to be the key parameter influencing the synchronization phenomenon. The effect of cylinder spacing on the wake synchronization and the hydrodynamic forces has been examined. In addition, a comparison of the drag forces for flow past transversely vibrating square and circular cylinders for similar amplitudes and frequencies of cylinder vibration has been presented while employing the tested computational code.

Pelvic floor muscle function in women with pelvic floor dysfunction

DEFF Research Database (Denmark)

Tibaek, Sigrid; Dehlendorff, Christian

2014-01-01

The objectives of this study were to investigate the level of pelvic floor muscle (PFM) function in women with pelvic floor dysfunction (PFD) referred by gynaecologists and urologists for in-hospital pelvic floor muscle training (PFMT), and to identity associated factors for a low level of PFM...

Equipment for inspection and carrying out repairs, if required, for tube bundles of steam raising units

International Nuclear Information System (INIS)

Gugel, G.

1976-01-01

The equipment solves the problem of being able to inspect and possibly to repair U-tubes of a vertical steam raising unit standing on a tube floor, without draining the primary medium and bringing the test equipment and tools into the inside of the boiler first. This is achieved by leaving a considerable part of the equipment permanently in the hemispherical space under the tube floor and operating it from the outside, on the other side of the concrete shielding. An inspection tube is threaded in turn horizontally through a concrete shield, a tube duct in the heat insulation of the steam raising unit, and through a hole in the hemispherical space under the tube floor into this space. The end of an angle tube can be moved axially from outside the concrete shield and can be rotated in a semicircle above the tube axis. By interposing a, for example, 12 part distributor with 12 short, differently bent tubes 12 adjacent tubes opening into the tube floor can be controlled and tested, by axial movement of the angle tube together with the distributor, e.g. 4 x 12 other U tubes. A turbulent flow sensor, for example, can be introduced through the angle tube and distributor. In the non-operational condition the equipment is moved into a recess via a supporting angle and stopped there. (ORU) [de

SUSTAINABLE TRAILER FLOORING

OpenAIRE

John Lu; Marc Chorney; Lowell Peterson

2009-01-01

Different trailer flooring materials, including wood-based, aluminum, steel, and synthetic plastic floors, were evaluated in accordance with their durability and sustainability to our natural environment. Wood-based trailer flooring is an eco-friendly product. It is the most sustainable trailer flooring material compared with fossil fuel-intensive steel, aluminum, and plastics. It is renewable and recyclable. Oak, hard maple, and apitong are strong and durable hardwood species that are curren...

Dynamic Friction Performance of a Pneumatic Cylinder with Al2O3 Film on Cylinder Surface.

Science.gov (United States)

Chang, Ho; Lan, Chou-Wei; Wang, Hao-Xian

2015-11-01

A friction force system is proposed for accurately measuring friction force and motion properties produced by reciprocating motion of piston in a pneumatic cylinder. In this study, the proposed system is used to measure the effects of lubricating greases of different viscosities on the friction properties of pneumatic cylinder, and improvement of stick-slip motion for the cylinder bore by anodizing processes. A servo motor-driven ball screw is used to drive the pneumatic cylinder to be tested and to measure the change in friction force of the pneumatic cylinder. Experimental results show, that under similar test conditions, the lubricating grease with viscosity VG100 is best suited for measuring reciprocating motion of the piston of pneumatic cylinder. The wear experiment showed that, in the Al2O3 film obtained at a preset voltage 40 V in the anodic process, the friction coefficient and hardness decreased by 55% and increased by 274% respectively, thus achieving a good tribology and wear resistance. Additionally, the amplitude variation in the friction force of the pneumatic cylinder wall that received the anodizing treatment was substantially reduced. Additionally, the stick-slip motion of the pneumatic cylinder during low-speed motion was substantially improved.

Generation of airborne Listeria innocua from model floor drains.

Science.gov (United States)

Berrang, Mark E; Frank, Joseph F

2012-07-01

Listeria monocytogenes can colonize floor drains in poultry processing and further processing facilities, remaining present even after cleaning and disinfection. Therefore, during wash down, workers exercise caution to avoid spraying hoses directly into drains in an effort to prevent the escape and transfer of drain microflora to food contact surfaces. The objective of this study was to examine the extent to which an inadvertent water spray into a colonized floor drain can cause the spread of airborne Listeria. Listeria innocua was used to inoculate a polyvinyl chloride model floor drain, resulting in approximately 10(8) cells per ml of phosphate-buffered saline and 10(4) attached cells per square centimeter of inner surface. Each model drain was subjected to a 2-s spray of tap water at 68.9 kPa from a distance of 1 m. Drains were sprayed while filled and again after emptying. Airborne cells were collected by using sedimentation plates containing Listeria selective agar which were placed on the floor and walls of a contained room at incremental horizontal and vertical distances of 0.6, 1.2, 2.4, or 4.0 m from the drain. Sedimentation plates were exposed for 10 min. A mechanical sampler was used to also collect air by impaction on the surface of Listeria selective agar to determine the number of cells per liter of air. The experiment was conducted in triplicate rooms for each of four replications. L. innocua was detected on sedimentation plates on the floor as far as 4.0 m from the drain and on walls as high as 2.4 m above the floor and 4 m from the drain. A 2-s spray with a water hose into a contaminated drain can cause airborne spread of Listeria, resulting in the potential for cross-contamination of food contact surfaces, equipment, and exposed product.

Evaluation of a RF-Based Approach for Tracking UF6 Cylinders at a Uranium Enrichment Plant

International Nuclear Information System (INIS)

Pickett, Chris A; Younkin, James R; Kovacic, Donald N; Laughter, Mark D; Hines, Jairus B; Boyer, Brian Martinez

2008-01-01

Approved industry-standard cylinders are used globally to handle and store uranium hexafluoride (UF 6 ) feed, product, tails, and samples at uranium enrichment plants. The International Atomic Energy Agency (IAEA) relies on time-consuming physical inspections to verify operator declarations and detect possible diversion of UF 6 . Development of a reliable, automated, and tamper-resistant system for near real-time tracking and monitoring UF 6 cylinders (as they move within an enrichment facility) would greatly improve the inspector function. This type of system can reduce the risk of false or misreported cylinder tare weights, diversion of nuclear material, concealment of excess production, utilization of undeclared cylinders, and misrepresentation of the cylinders contents. This paper will describe a proof-of-concept approach that was designed to evaluate the feasibility of using radio frequency (RF)-based technologies to track individual UF 6 cylinders throughout a portion of their life cycle, and thus demonstrate the potential for improved domestic accountability of materials, and a more effective and efficient method for application of site-level IAEA safeguards. The evaluation system incorporates RF-based identification devices (RFID) which provide a foundation for establishing a reliable, automated, and near real-time tracking system that can be set up to utilize site-specific, rules-based detection algorithms. This paper will report results from a proof-of-concept demonstration at a real enrichment facility that is specifically designed to evaluate both the feasibility of using RF to track cylinders and the durability of the RF equipment to survive the rigors of operational processing and handling. The paper also discusses methods for securely attaching RF devices and describes how the technology can effectively be layered with other safeguard systems and approaches to build a robust system for detecting cylinder diversion. Additionally, concepts for off

Generation of floor response spectra for mixed-oxide fuel fabrication plants

International Nuclear Information System (INIS)

Arthur, D.F.; Murray, R.C.; Tokarz, F.J.

1975-01-01

Floor or amplified response spectra are generally used as input motion for seismic analysis of critical equipment and piping in nuclear power plants and related facilities. The floor spectra are normally the result of a time-history calculation of building response to ground shaking. However, alternate approximate methods have been suggested by both Kapur and Biggs. As part of a study for the Nuclear Regulatory Commission horizontal floor response spectra were generated and compared by all three methods. The dynamic analyses were performed on a model of the Westinghouse Recycle Fuels Plant Manufacturing Building (MOFFP). Input to the time-history calculations was a synthesized accelerogram whose response spectrum is similar to that in Regulatory Guide 1.60. The response spectrum of the synthetic ground motion was used as input to the Kapur and Biggs methods. Calculations were performed for both hard (3500 fps) and soft (1500 fps) foundation soils. Results of comparison of the three methods indicate that although the approximate methods could easily be made acceptable from a safety standpoint, they would be overly conservative. The time-history method will yield floor spectra which are less uncertain and less conservative for a relatively modest additional effort. (auth)

Buckling Analysis for Stiffened Anisotropic Circular Cylinders Based on Sanders Nonlinear Shell Theory

Science.gov (United States)

Nemeth, Michael P.

2014-01-01

Nonlinear and bifurcation buckling equations for elastic, stiffened, geometrically perfect, right-circular cylindrical, anisotropic shells subjected to combined loads are presented that are based on Sanders' shell theory. Based on these equations, a three-parameter approximate Rayleigh-Ritz solution and a classical solution to the buckling problem are presented for cylinders with simply supported edges. Extensive comparisons of results obtained from these solutions with published results are also presented for a wide range of cylinder constructions. These comparisons include laminated-composite cylinders with a wide variety of shell-wall orthotropies and anisotropies. Numerous results are also given that show the discrepancies between the results obtained by using Donnell's equations and variants of Sanders' equations. For some cases, nondimensional parameters are identified and "master" curves are presented that facilitate the concise representation of results.

Exercise Equipment Usability Assessment for a Deep Space Concept Vehicle

Science.gov (United States)

Rhodes, Brooke M.; Reynolds, David W.

2015-01-01

With international aspirations to send astronauts to deep space, the world is now faced with the complex problem of keeping astronauts healthy in unexplored hostile environments for durations of time never before attempted by humans. The great physical demands imparted by space exploration compound the problem of astronaut health, as the astronauts must not only be healthy, but physically fit upon destination arrival in order to perform the scientific tasks required of them. Additionally, future deep space exploration necessitates the development of environments conducive to long-duration habitation that would supplement propulsive vehicles. Space Launch System (SLS) core stage barrel sections present large volumes of robust structure that can be recycled and used for long duration habitation. This assessment will focus on one such conceptual craft, referred to as the SLS Derived Habitat (SLS-DH). Marshall Space Flight Center's (MSFC) Advanced Concepts Office (ACO) has formulated a high-level layout of this SLS-DH with parameters such as floor number and orientation, floor designations, grid dimensions, wall placement, etc. Yet to be determined, however, is the layout of the exercise area. Currently the SLS-DH features three floors laid out longitudinally, leaving 2m of height between the floor and ceilings. This short distance between levels introduces challenges for proper placement of exercise equipment such as treadmills and stationary bicycles, as the dynamic envelope for the 95th percentile male astronauts is greater than 2m. This study aims to assess the optimal equipment layout and sizing for the exercise area of this habitat. Figure 1 illustrates the layout of the DSH concept demonstrator located at MSFC. The exercise area is located on the lower level, seen here as the front half of the level occupied by a crew member. This small volume does not allow for numerous or bulky exercise machines, so the conceptual equipment has been limited to a treadmill and

Wear resistance and electrical properties of functionally graded epoxy-resin/silica composites

International Nuclear Information System (INIS)

Rihan, Y. A.; Abd El-Bary, B.

2012-12-01

In this paper graded Silica/Epoxy composite fabricated by controlled mold filling to obtain a stepwise graded structure. The generated graded structure was controlled by the w 1% content of silica particulates of size range from (45 μm-250 μm). Microstructural characterization was conducted using Scanning Electron Microscope (SEM). Electrical properties were conducted in High Voltage-Lab using Sphere-Plate Electrode System and Insulating resistance equipment s. Wear characteristics were studied using Block-on-Ring wear testing machine for the different layers of the graded silica/epoxy composites, The prepared materials are used as coating materials for the floors of chemical laboratories. (Author)

48 CFR 52.247-66 - Returnable Cylinders.

Science.gov (United States)

2010-10-01

... Cylinders (MAY 1994) (a) Cylinder, referred to in this clause, is a pressure vessel designed for pressures... clause. (c) For each cylinder lost or damaged beyond repair while in the Government's possession, the... associated replacement values.] These cylinders shall become Government property. (d) If any lost cylinder is...

Availability of Life Support Equipment and its Utilization by Ambulance Drivers.

Science.gov (United States)

Acharya, Rija; Badhu, Angur; Shah, Tara; Shrestha, Sharmila

2017-09-08

An effective ambulance is a vital requirement for providing an emergency medical service. Well-equipped ambulances with trained paramedics can save many lives during the golden hours of trauma care. The objective was to document the availability and utilization of basic life support equipment in the ambulances and to assess knowledge on first aid among the drivers. Descriptive design was used. Total of 109 ambulances linked to B.P. Koirala Institute of Health Sciences were enrolled using purposive sampling method. Self- constructed observation checklist and semi structured interview schedule was used for data collection. More than half of the respondents had less than five years of experience and were not trained in first aid. About two-third of the respondents had adequate knowledge on first aid. About 90% of the ambulance had oxygen cylinder and adult oxygen mask which was 'usually' used equipment. More than half of ambulance had equipment less than 23% as compared to that of national guidelines. There was significant association of knowledge with the experience (p = 0.004) and training (p = 0.001). Availability of equipment was associated with training received (p = 0.007),organization (p= 0.032)and district (p = 0.023) in which the ambulance is registered. The study concludes that maximum ambulance linked to BPKIHS, Nepal did not have even one fourth of the equipment for basic life support. Equipment usually used was oxygen cylinder and oxygen mask. Majority of driver had adequate knowledge on first aid and it was associated with training and experience.

Thermal design of a modern, two floor, zero energy house in a desert compound

KAUST Repository

Serag-Eldin, M. A.

2010-01-01

The paper presents a thermal analysis and design of a fully equipped, air-conditioned, zero energy house located in a desert compound at 24.5° latitude. Unlike previous designs the home is two floors high, which makes the balancing of energy supply

Flow over an inline oscillating circular cylinder in the wake of a stationary circular cylinder

Energy Technology Data Exchange (ETDEWEB)

Zhang, Yang; Zhu, Keqiang, E-mail: zhukeqiang@nbu.edu.cn [Faculty of Maritime and Transportation, Ningbo University, Ningbo 315211 (China)

2017-02-15

Flow interference between an upstream stationary cylinder and an inline oscillating cylinder is studied with the lattice Boltzmann method. With a fixed Reynolds number Re  = 100 and pitch ratio L / D  = 4, the effects of oscillation amplitude A / D  = [0.25, 1] and frequency f {sub e}/ f {sub s} = [0.5, 2] are investigated. The wake response state is categorized into lock-in and non-lock-in. The lock-in zone in the bifurcation diagram of amplitude versus frequency is discontinuous. Response states of upstream and downstream wakes are similar under the conditions of small amplitude or low frequency. However, with large oscillating parameters, the two wakes are prone to be in different states as the flow field becomes irregular. Two distinct flow regimes have been identified, i.e., single-cylinder and two-cylinder shedding regimes. The presence of single-cylinder shedding regime is attributed to the low shedding frequency of the downstream cylinder at large amplitude. Hydrodynamic forces of the oscillating tandem system are discussed. The results reveal that forces on the two cylinders behave differently and that the absence of vortices in the gap flow significantly reduces the forces exerting on the tandem system. (paper)

Numerical analysis of some problems related to the mechanics of pneumatic tires: Finite deformation/rolling contact of a viscoelastic cylinder and finite deformation of cord-reinforced rubber composites

Science.gov (United States)

Oden, J. T.; Becker, E. B.; Lin, T. L.; Hsieh, K. T.

1984-01-01

The formulation and numerical analysis of several problems related to the behavior of pneumatic tires are considered. These problems include the general rolling contact problem of a rubber-like viscoelastic cylinder undergoing finite deformations and the finite deformation of cord-reinforced rubber composites. New finite element models are developed for these problems. Numerical results obtained for several representative cases are presented.

Swap your propane cylinder with SWOP

International Nuclear Information System (INIS)

Anon.

1997-01-01

A very successful propane cylinder exchange program operated by South Western Ontario Propane (SWOP) Inc., was described. The company specializes in propane cylinder exchange and in the refurbishing and marketing of top quality domestic and commercial propane cylinders. The company, currently operating out of Bradford, Ontario, was started in 1991. It employs a staff of 25 in peak season. It has some 200 exchange outlets throughout Ontario and has accepted outdated tanks from as far west as Manitoba and as far east as Quebec. A typical transaction involves bringing an empty cylinder to the nearest SWOP location and exchanging it for a full SWOP cylinder. SWOP does about 50,000 to 60,000 exchanges a year. For the consumer, the program is said to be cheaper, safer and more convenient than getting refills. As far as dealers are concerned operating a SWOP exchange outlet can add extra profits, attract new customers, and build additional consumer loyalty without the need for extra staff or additional indoor space. SWOP delivers full cylinders to exchange outlets on a weekly basis when it also picks up the empty cylinders. At dealer locations, the cylinders (full or empty) are stored in company -designed vandal-proof metal cages. Major expansion of the network of outlets and the cylinder refurbishing and refilling facilities are planned for 1998

Life Prediction on a T700 Carbon Fiber Reinforced Cylinder with Limited Accelerated Life Testing Data

Directory of Open Access Journals (Sweden)

Ma Xiaobing

2015-01-01

Full Text Available An accelerated life testing investigation was conducted on a composite cylinder that consists of aluminum alloy and T700 carbon fiber. The ultimate failure stress predictions of cylinders were obtained by the mixing rule and verified by the blasting static pressure method. Based on the stress prediction of cylinder under working conditions, the constant stress accelerated life test of the cylinder was designed. However, the failure data cannot be sufficiently obtained by the accelerated life test due to the time limitation. Therefore, most of the data presented to be high censored in high stress level and zero-failure data in low stress level. When using the traditional method for rupture life prediction, the results showed to be of lower confidence. In this study, the consistency of failure mechanism for carbon fiber and cylinder was analyzed firstly. According to the analysis result, the statistical test information of carbon fiber could be utilized for the accelerated model constitution. Then, rupture life prediction method for cylinder was proposed based on the accelerated life test data and carbon fiber test data. In this way, the life prediction accuracy of cylinder could be improved obviously, and the results showed that the accuracy of this method increased by 35%.

Fire testing of bare uranium hexafluoride cylinders

Energy Technology Data Exchange (ETDEWEB)

Pryor, W.A. [PAI Corp., Oak Rige, TN (United States)

1991-12-31

In 1965, the Oak Ridge Gaseous Diffusion Plant (ORGDP), now the K-25 Site, conducted a series of tests in which bare cylinders of uranium hexafluoride (UF{sub 6}) were exposed to engulfing oil fires for the US Atomic Energy Commission (AEC), now the US Department of Energy (DOE). The tests are described and the results, conclusions, and observations are presented. Two each of the following types of cylinders were tested: 3.5-in.-diam {times} 7.5-in.-long cylinders of Monel (Harshaw), 5.0-in.-diam {times} 30-in.-long cylinders of Monel, and 8-in.-diam {times} 48-in.-long cylinders of nickel. The cylinders were filled approximately to the standard UF{sub 6} fill limits of 5, 55, and 250 lb, respectively, with a U-235 content of 0.22%. The 5-in.- and 8-in.-diam cylinders were tested individually with and without their metal valve covers. For the 3.5-in.-diam Harshaw cylinders and the 5.0-in.-diam cylinder without a valve cover the valves failed and UF{sub 6} was released. The remaining cylinders ruptured explosively in time intervals ranging from about 8.5 to 11 min.

Fire testing of bare uranium hexafluoride cylinders

Energy Technology Data Exchange (ETDEWEB)

Pryor, W.A. [PAI Corp., Oak Ridge, TN (United States)

1991-12-31

In 1965, the Oak Ridge Gaseous Diffusion Plant (ORGDP), now the K-25 Site, conducted a series of tests in which bare cylinders of uranium hexafluoride (UF{sub 6}) were exposed to engulfing oil fires for the US Atomic Energy Commission (AEC), now the US Department of Energy (DOE). The tests are described and the results, conclusions, and observations are presented. Two each of the following types of cylinders were tested: 3.5-in.-diam {times} 7.5-in.-long cylinders of Monel (Harshaw), 5.0-in.-diam {times} x 30-in.-long cylinders of Monel, and 8-in.-diam {times} 48-in.-long cylinders of nickel. The cylinders were filled approximately to the standard UF{sub 6} fill limits of 5, 55, and 250 lb, respectively, with a U-235 content of 0.22%. The 5-in.- and 8-in.-diam cylinders were tested individually with and without their metal valve covers. For the 3.5-in.-diam Harshaw cylinders and the 5.0-in.-diam cylinder without a valve cover, the valves failed and UF{sub 6} was released. The remaining 6 cylinders ruptured explosively in time intervals ranging from about 8.5 to 11 min.

A study on the detection of misfiring cylinder of the diesel engine in excavation machinery using improved ALM analysis

Energy Technology Data Exchange (ETDEWEB)

Nagayama, M.; Kawamura, Y. [Tsukuba Univ., Tsukuba, Ibaraki (Japan); Ujihira, M. [Hokkaido Univ., Sapporo (Japan). School of Engineering; Akhmetov, D.F.; Ito, F.; Aoshima, N. [NTT DoCoMo Inc. (Japan)

2005-07-01

Mechanical problems in large-scale mining equipment can result in serious losses in operational efficiency and profits. A misfiring cylinder in a diesel engine can cause engine failure in a short period of time. Regular maintenance and inspection of machinery is therefore critical for mining and construction operations. For that reason, an innovative method was developed to detect whether a cylinder is misfiring, and if so, which one. This study established a simple, reliable and sure method using the improved aggregative learning method (ALM) analysis for the early diagnosis and repair of misfiring cylinders. A minimum number of sensors were applied on the side of 2 cylinders on a diesel engine in order to set up an abnormal diagnostic system that detects anomalies at an early stage by analyzing the acceleration waveform using the ALM method. The detection method is better than traditional methods that require accelerometers. 6 refs., 1 tab., 5 figs.

Determination of the theoretical feasibility for the transmutation of europium isotopes from high flux isotope reactor control cylinders

International Nuclear Information System (INIS)

Elam, K.R.; Reich, W.J.

1995-09-01

The High Flux Isotope Reactor (HFIR) at the Oak Ridge National Laboratory (ORNL) is a 100 MWth light-water research reactor designed and built in the 1960s primarily for the production of transuranic isotopes. The HFIR is equipped with two concentric cylindrical blade assemblies, known as control cylinders, that are used to control reactor power. These control cylinders, which become highly radioactive from neutron exposure, are periodically replaced as part of the normal operation of the reactor. The highly radioactive region of the control cylinders is composed of europium oxide in an aluminum matrix. The spent HFIR control cylinders have historically been emplaced in the ORNL Waste Area Grouping (WAG) 6. The control cylinders pose a potential radiological hazard due to the long lived radiotoxic europium isotopes 152 Eu, 154 Eu, and 155 Eu. In a 1991 health evaluation of WAG 6 (ERD 1991) it was shown that these cylinders were a major component of the total radioactivity in WAG 6 and posed a potential exposure hazard to the public in some of the postulated assessment scenarios. These health evaluations, though preliminary and conservative in nature, illustrate the incentive to investigate methods for permanent destruction of the europium radionuclides. When the cost of removing the control cylinders from WAG 6, performing chemical separations and irradiating the material in HFIR are factored in, the option of leaving the control cylinders in place for decay must be considered. Other options, such as construction of an engineered barrier around the disposal silos to reduce the chance of migration, should also be analyzed

Flow past a rotating cylinder

Science.gov (United States)

Mittal, Sanjay; Kumar, Bhaskar

2003-02-01

Flow past a spinning circular cylinder placed in a uniform stream is investigated via two-dimensional computations. A stabilized finite element method is utilized to solve the incompressible Navier Stokes equations in the primitive variables formulation. The Reynolds number based on the cylinder diameter and free-stream speed of the flow is 200. The non-dimensional rotation rate, [alpha] (ratio of the surface speed and freestream speed), is varied between 0 and 5. The time integration of the flow equations is carried out for very large dimensionless time. Vortex shedding is observed for [alpha] cylinder. The results from the stability analysis for the rotating cylinder are in very good agreement with those from direct numerical simulations. For large rotation rates, very large lift coefficients can be obtained via the Magnus effect. However, the power requirement for rotating the cylinder increases rapidly with rotation rate.

An Operator Perspective from a Facility Evaluation of an RFID-Based UF6 Cylinder Accounting and Tracking System

International Nuclear Information System (INIS)

Martyn, Rose; Fitzgerald, Peter; Stehle, Nicholas D.; Rowe, Nathan C.; Younkin, James R.

2011-01-01

An operational field test of a Radio-Frequency Identification (RFID) system for tracking and accounting UF6 cylinders was conducted at the Global Nuclear Fuel Americas (GNF) fuel fabrication plant in 2009. The Cylinder Accountability and Tracking System (CATS) was designed and deployed by Oak Ridge National Laboratory (ORNL) and evaluated in cooperation with GNF. The system required that passive RFID be attached to several UF6 30B cylinders as they were received at the site; then the cylinders were tracked as they proceeded to interim storage, to processing in an autoclave, and eventually to disposition from the site. This CATS deployment also provided a direct integration of scale data from the site accountability scales. The integration of this information into the tracking data provided an attribute for additional safeguards for evaluation. The field test provided insight into the advantages and challenges of using RFID at an operating nuclear facility. The RFID system allowed operators to interact with the technology and demonstrated the survivability of the tags and reader equipment in the process environment. This paper will provide the operator perspective on utilizing RFID technology for locating cylinders within the facility, thereby tracking the cylinders for process and for Material Control and Accounting functions. The paper also will present the operator viewpoint on RFID implemented as an independent safeguards system.

Introductory guide to floors and flooring

CSIR Research Space (South Africa)

Billingham, PA

1977-01-01

Full Text Available not make use of the warming and cooling effects of direct contact with the ground. Indeed the precautions that are necessary to protect such floors against damp and decay may actually reduce the comfort levels within a house. This is because there is a... with resultant discomfort and extra heating costs. Today, in South Africa, most modern homesareof singlestorey con- struction with aconcrete floor slab in direct contact with theground which once again makes its full contribution to the comfort and structural...

IEEE 693 seismic qualification of composites for substation high-voltage equipment

Energy Technology Data Exchange (ETDEWEB)

Schiff, A.J. [Precision Measurement Instruments, Los Altos Hills, CA (United States); Kempner, L.Jr. [Bonneville Power Administration, Vancouver, BC (Canada)

2004-07-01

Standard 693-1997 of the Institute of Electrical and Electronic Engineers (IEEE) is the recommended practice for seismic design of substations. It represents a significant improvement in the way the power industry seismically qualifies substation high-voltage equipment. This paper described the use of IEEE Standard 693 for hollow-core composite insulators that are used on high-voltage transformers and demonstrated that changes are warranted. The following four failure modes associated with the composite insulator were discussed: bond degradation, bond failure, tube degradation and tube layer delamination. The authors evaluated the IEEE 693 qualification procedure of time history shake-table and static-pull tests and were concerned about acceptance criteria. It was shown that acceptance criteria are not valid for qualifying hollow-core composites and that static-pull tests are needed after the vibration qualification tests are completed. It was suggested that more research is warranted to determine if bonding at the top part of the flange can be eliminated, thereby eliminating bond degradation. The resulting increase in system damping would improve the dynamic response of the unit. 1 ref., 10 figs.

Sub-wavelength resonances in polygonal metamaterial cylinders

DEFF Research Database (Denmark)

Arslanagic, Samel; Breinbjerg, Olav

2008-01-01

It has been shown that the sub-wavelength resonances of circular MTM cylinders also occur for polygonal MTM cylinders. This is the case for lossless and non-dispersive cylinders as well as lossy and dispersive cylinders. The sub-wavelength resonances are thus not limited to structures of canonical...

UF{sub 6} cylinder inspections at PGDP

Energy Technology Data Exchange (ETDEWEB)

Lamb, G.W.; Whinnery, W.N. [Martin Marietta Energy Systems, Inc., Paducah, KY (United States)

1991-12-31

Routine inspections of all UF{sub 6} cylinders at the Paducah Gaseous Diffusion Plant have been mandated by the Department of Energy. A specific UF{sub 6} cylinder inspection procedure for what items to inspect and training for the operators prior to inspection duty are described. The layout of the cylinder yards and the forms used in the inspections are shown. The large number of cylinders (>30,000) to inspect and the schedule for completion on the mandated time table are discussed. Results of the inspections and the actions to correct the deficiencies are explained. Future inspections and movement of cylinders for relocation of certain cylinder yards are defined.

Mechanical Cushion Design Influence on Cylinder Dynamics

DEFF Research Database (Denmark)

Borghi, Massimo; Milani, Massimo; Conrad, Finn

2005-01-01

. experimental comparison, involving the piston velocity and the cylinder chambers pressure. After, with the aim of highlighting the effect of mechanical cushions design on a two effect linear actuator dynamic performances, the characteristics modulation of four alternative cushioning systems are determined......The paper deals with the simulation and the experimental verification of the dynamic behaviour of a linear actuator equipped with different configurations of mechanical cushion. A numerical model, developed and tailored to describe the influence of different modulation of the discharged flow......-rate (and of the correspondent discharging orifice design) on the cushioning characteristics variation is firstly introduced. Then, with respect to the case of the cylindrical cushioning engagement, both the reliability and the limits of the numerical approach are highlighted through a numerical vs...

Approximation by Cylinder Surfaces

DEFF Research Database (Denmark)

Randrup, Thomas

1997-01-01

We present a new method for approximation of a given surface by a cylinder surface. It is a constructive geometric method, leading to a monorail representation of the cylinder surface. By use of a weighted Gaussian image of the given surface, we determine a projection plane. In the orthogonal...

Investigation of floor Nusselt number in floor heating system for insulated ceiling conditions

International Nuclear Information System (INIS)

Karadag, Refet; Teke, Ismail

2007-01-01

In this study, in a floor heated room, natural convection heat transfer over the floor is analysed numerically for different thermal conditions. An equation relevant to Nusselt number over the floor has been obtained by using the numerical data. Different equations are given in the literature. They consider the effect of floor Rayleigh number while neglecting the effect of wall and ceiling thermal conditions. Numerical data obtained in this study show that the Nusselt number over the floor depends on not only the floor Rayleigh number but also the wall Rayleigh number (for insulated ceiling conditions). The equations given in the literature are different from each other due to their not considering the effect of wall and ceiling Rayleigh numbers. This difference between the equations may be eliminated by obtaining an equation containing the effect of floor, wall and ceiling Rayleigh numbers. In this new approach, an equation relevant to the floor Nusselt number that depends on the floor and wall Rayleigh numbers has been obtained in the floor heating system for insulated ceiling conditions. The equation obtained in this study has been compared with the equations given in the literature. It has been seen that the equation obtained in this study matches the numerical values under more extensive thermal conditions than the equations given in the literature. The maximum deviation for the equations given in the literature is 35%, but in the current study, the maximum deviation has been found to be 10%. As a result, it is more convenient to use the equation found in the new approach as a function of Rayleigh number over the floor and wall for insulated ceiling conditions

Theoretical and experimental stress analyses of ORNL thin-shell cylinder-to-cylinder model 2

International Nuclear Information System (INIS)

Gwaltney, R.C.; Bolt, S.E.; Bryson, J.W.

1975-10-01

Model 2 in a series of four thin-shell cylinder-to-cylinder models was tested, and the experimentally determined elastic stress distributions were compared with theoretical predictions obtained from a thin-shell finite-element analysis. Both the cylinder and the nozzle of model 2 had outside diameters of 10 in., giving a d 0 /D 0 ratio of 1.0, and both had outside diameter/thickness ratios of 100. Sixteen separate loading cases in which one end of the cylinder was rigidly held were analyzed. An internal pressure loading, three mutually perpendicular force components, and three mutually perpendicular moment components were individually applied at the free end of the cylinder and at the end of the nozzle. In addition to these 13 loadings, 3 additional loads were applied to the nozzle (in-plane bending moment, out-of-plane bending moment, and axial force) with the free end of the cylinder restrained. The experimental stress distributions for each of the 16 loadings were obtained using 152 three-gage strain rosettes located on the inner and outer surfaces. All the 16 loading cases were also analyzed theoretically using a finite-element shell analysis. The analysis used flat-plate elements and considered five degrees of freedom per node in the final assembled equations. The comparisons between theory and experiment show reasonably good general agreement, and it is felt that the analysis would be satisfactory for most engineering purposes. (auth)

Novel AC Servo Rotating and Linear Composite Driving Device for Plastic Forming Equipment

Science.gov (United States)

Liang, Jin-Tao; Zhao, Sheng-Dun; Li, Yong-Yi; Zhu, Mu-Zhi

2017-07-01

The existing plastic forming equipment are mostly driven by traditional AC motors with long transmission chains, low efficiency, large size, low precision and poor dynamic response are the common disadvantages. In order to realize high performance forming processes, the driving device should be improved, especially for complicated processing motions. Based on electric servo direct drive technology, a novel AC servo rotating and linear composite driving device is proposed, which features implementing both spindle rotation and feed motion without transmission, so that compact structure and precise control can be achieved. Flux switching topology is employed in the rotating drive component for strong robustness, and fractional slot is employed in the linear direct drive component for large force capability. Then the mechanical structure for compositing rotation and linear motion is designed. A device prototype is manufactured, machining of each component and the whole assembly are presented respectively. Commercial servo amplifiers are utilized to construct the control system of the proposed device. To validate the effectiveness of the proposed composite driving device, experimental study on the dynamic test benches are conducted. The results indicate that the output torque can attain to 420 N·m and the dynamic tracking errors are less than about 0.3 rad in the rotating drive. the dynamic tracking errors are less than about 1.6 mm in the linear feed. The proposed research provides a method to construct high efficiency and accuracy direct driving device in plastic forming equipment.

Effect of pelvic floor rehabilitation technique in preventing the postpartum pelvic floor dysfunction

Directory of Open Access Journals (Sweden)

Shi-Qiong Li

2017-04-01

Full Text Available Objective: To explore the effect of pelvic floor rehabilitation technique in preventing the postpartum pelvic floor dysfunction and on the sexual life quality. Methods: A total of 286 puerpera with pelvic floor dysfunction who were admitted in our hospital from May, 2014 to May, 2015 42 d after delivery were included in the study, and randomized into the treatment group and the control group with 143 cases in each group. After guidance, the puerpera in the control group were given pelvic floor muscle training by themselves at home. On this basis, the puerpera in the treatment group were treated by the pelvic floor rehabilitation apparatus. The puerpera in the two groups were treated for 4 weeks. The pelvic floor function before treatment, 6 months and 1 year after delivery was detected. The color Doppler ultrasound apparatus was used to detect BSD, PUVA, UVJ-M, and BND 3 months after delivery. Results: BND, PUVA-R, PUVA-S, and UVJ-M 3 months after delivery in the treatment groups were significantly lower than those in the control group, while BSD-S was significantly higher than that in the control group. The improvement of type I and II muscle fiber fatigue (%, POP-Q degree, AP indication point (cm, and vaginal dynamic pressure (cmH2O was significantly superior to that in the control group. The comparison of pelvic floor muscle strength classification before treatment between the two groups was not statistically significant. After treatment, the pelvic floor muscle in the two groups was significantly strengthened, and the proportion of V grade patients was significantly increased when compared with before treatment. Conclusions: The postpartum early pelvic floor rehabilitation technique can effectively enhance the pelvic floor function, and prevent the postpartum pelvic floor dysfunction, with an accurate efficacy; therefore, it deserves to be widely recommended in the clinic.

235U enrichment determination on UF6 cylinders with CZT detectors

Science.gov (United States)

Berndt, Reinhard; Mortreau, Patricia

2018-04-01

Measurements of uranium enrichment in UF6 transit cylinders are an important nuclear safeguards verification task, which is performed using a non-destructive assay method, the traditional enrichment meter, which involves measuring the count rate of the 186 keV gamma ray. This provides a direct measure of the 235U enrichment. Measurements are typically performed using either high-resolution detectors (Germanium) with e-cooling and battery operation, or portable devices equipped with low resolution detectors (NaI). Despite good results being achieved when measuring Low Enriched Uranium in 30B type cylinders and natural uranium in 48Y type containers using both detector systems, there are situations, which preclude the use of one or both of these systems. The focus of this work is to address some of the recognized limitations in relation to the current use of the above detector systems by considering the feasibility of an inspection instrument for 235U enrichment measurements on UF6 cylinders using the compact and light Cadmium Zinc Telluride (CZT) detectors. In the present work, test measurements were carried out, under field conditions and on full-size objects, with different CZT detectors, in particular for situations where existing systems cannot be used e.g. for stacks of 48Y type containers with depleted uranium. The main result of this study shows that the CZT detectors, actually a cluster of four μCZT1500 micro spectrometers provide as good results as the germanium detector in the ORTEC Micro-trans SPEC HPGe Portable spectrometer, and most importantly in particular for natural and depleted uranium in 48Y cylinders.

Pressure cylinders under fire condition

Directory of Open Access Journals (Sweden)

Jan Hora

2016-03-01

Full Text Available The presence of pressure cylinders under fire conditions significantly increases the risk rate for the intervening persons. It is considerably problematic to predict the pressure cylinders behaviour during heat exposition, its destruction progress and possible following explosion of the produced air–gas mixture because pressure cylinders and its environment generate a highly complicated dynamic system during an uncontrolled destruction. The large scale tests carried out by the Pilsen Fire and Rescue Department and the Rapid Response Unit of the Czech Republic Police in October 2012 and in May 2014 in the Military area Brdy and in the area of the former Lachema factory in Kaznějov had several objectives, namely, to record, qualify and quantify some of the aspects of an uncontrolled heat destruction procedure of an exposed pressure cylinder in an enclosed space and to qualify and describe the process of a controlled destruction of a pressure cylinder by shooting through it including basic tactical concepts. The article describes the experiments that were carried out.

Uncertainty in the analysis of the overall equipment effectiveness on the shop floor

Science.gov (United States)

Rößler, M. P.; Abele, E.

2013-06-01

In this article an approach will be presented which supports transparency regarding the effectiveness of manufacturing equipment by combining the fuzzy set theory with the method of the overall equipment effectiveness analysis. One of the key principles of lean production and also a fundamental task in production optimization projects is the prior analysis of the current state of a production system by the use of key performance indicators to derive possible future states. The current state of the art in overall equipment effectiveness analysis is usually performed by cumulating different machine states by means of decentralized data collection without the consideration of uncertainty. In manual data collection or semi-automated plant data collection systems the quality of derived data often diverges and leads optimization teams to distorted conclusions about the real optimization potential of manufacturing equipment. The method discussed in this paper is to help practitioners to get more reliable results in the analysis phase and so better results of optimization projects. Under consideration of a case study obtained results are discussed.

Uncertainty in the analysis of the overall equipment effectiveness on the shop floor

International Nuclear Information System (INIS)

Rößler, M P; Abele, E

2013-01-01

In this article an approach will be presented which supports transparency regarding the effectiveness of manufacturing equipment by combining the fuzzy set theory with the method of the overall equipment effectiveness analysis. One of the key principles of lean production and also a fundamental task in production optimization projects is the prior analysis of the current state of a production system by the use of key performance indicators to derive possible future states. The current state of the art in overall equipment effectiveness analysis is usually performed by cumulating different machine states by means of decentralized data collection without the consideration of uncertainty. In manual data collection or semi-automated plant data collection systems the quality of derived data often diverges and leads optimization teams to distorted conclusions about the real optimization potential of manufacturing equipment. The method discussed in this paper is to help practitioners to get more reliable results in the analysis phase and so better results of optimization projects. Under consideration of a case study obtained results are discussed.

Fire exposure of empty 30B cylinders

Energy Technology Data Exchange (ETDEWEB)

Ziehlke, K.T. [MJB Technical Associates, Inc., Knoxville, TN (United States)

1991-12-31

Cylinders for UF{sub 6} handling, transport, and storage are designed and built as unfired pressure vessels under ASME Boiler and Pressure Vessel Code criteria and standards. They are normally filled and emptied while UF{sub 6} is in its liquid phase. Transport cylinders such as the Model 30B are designed for service at 200 psi and 250{degrees}F, to sustain the process conditions which prevail during filling or emptying operations. While in transport, however, at ambient temperature the UF{sub 6} is solid, and the cylinder interior is well below atmospheric pressure. When the cylinders contain isotopically enriched product (above 1.0 percent U-235), they are transported in protective overpacks which function to guard the cylinders and their contents against thermal or mechanical damage in the event of possible transport accidents. Two bare Model 30B cylinders were accidentally exposed to a storage warehouse fire in which a considerable amount of damage was sustained by stored materials and the building structure, as well as by the cylinder valves and valve protectors. The cylinders were about six years old, and had been cleaned, inspected, hydrotested, and re-certified for service, but were still empty at the time of the fire. The privately-owned cylinders were transferred to DOE for testing and evaluation of the fire damage.

Decontamination of floor surfaces

International Nuclear Information System (INIS)

Smirous, F.

1983-01-01

Requirements are presented put on the surfaces of floors of radiochemical workplaces. The mechanism is described of retaining the contaminant in the surface of the flooring, ways of reducing the hazards of floor surface contamination, decontamination techniques and used decontamination agents. (J.P.)

Multiple Cylinder Free-Piston Stirling Machinery

Science.gov (United States)

Berchowitz, David M.; Kwon, Yong-Rak

In order to improve the specific power of piston-cylinder type machinery, there is a point in capacity or power where an advantage accrues with increasing number of piston-cylinder assemblies. In the case of Stirling machinery where primary energy is transferred across the casing wall of the machine, this consideration is even more important. This is due primarily to the difference in scaling of basic power and the required heat transfer. Heat transfer is found to be progressively limited as the size of the machine increases. Multiple cylinder machines tend to preserve the surface area to volume ratio at more favorable levels. In addition, the spring effect of the working gas in the so-called alpha configuration is often sufficient to provide a high frequency resonance point that improves the specific power. There are a number of possible multiple cylinder configurations. The simplest is an opposed pair of piston-displacer machines (beta configuration). A three-cylinder machine requires stepped pistons to obtain proper volume phase relationships. Four to six cylinder configurations are also possible. A small demonstrator inline four cylinder alpha machine has been built to demonstrate both cooling operation and power generation. Data from this machine verifies theoretical expectations and is used to extrapolate the performance of future machines. Vibration levels are discussed and it is argued that some multiple cylinder machines have no linear component to the casing vibration but may have a nutating couple. Example applications are discussed ranging from general purpose coolers, computer cooling, exhaust heat power extraction and some high power engines.

A method to generate generic floor response spectra for operating nuclear power plants

International Nuclear Information System (INIS)

Curreri, J.; Costantino, C.; Subudhi, M.; Reich, M.

1985-01-01

A free-field earthquake response spectra was used to generate horizontal earthquake time histories. The excitation was applied through the soil and into the various structures to produce responses in equipment. An entire range of soil conditions was used with each structure, from soft soil to solid rock. Actual PWR and BWR - Mark I structural models were used as representative of a class of structures. For each model, the stiffness properties were varied, with the same mass, so as to extend the fundamental base structure natural frequency from 2 cps to 36 cps. This resulted in fundamental mode coupled natural frequencies as low as 0.86 cps and as high as 30 cps. From all of these models of soils and structures, floor response spectra were generated at each floor level. The natural frequencies of the structures were varied to obtain maximum response conditions. The actual properties were first used to locate the natural frequencies. The stiffness properties were than varied, with the same mass, to extend the range of the fundamental base structure natural frequency. The intention was to have the coupled structural material frequencies in the vicinity of the peak amplitude frequency content of the excitation spectrum. Particular attention was therefore given to the frequency band between 2 Hz and 4 Hz. A horizontal generic floor response spectra is proposed for the top level of a generic structure. Reduction factors are applied to the peak acceleration for equipment at lower levels. (orig./HP)

Natural convective heat transfer from square cylinder

Energy Technology Data Exchange (ETDEWEB)

Novomestský, Marcel, E-mail: marcel.novomestsky@fstroj.uniza.sk; Smatanová, Helena, E-mail: helena.smatanova@fstroj.uniza.sk; Kapjor, Andrej, E-mail: andrej.kapjor@fstroj.uniza.sk [University of Žilina, Faculty of Mechanical Engineering, Department of Power Engineering, Univerzitná 1, 010 26 Žilina (Slovakia)

2016-06-30

This article is concerned with natural convective heat transfer from square cylinder mounted on a plane adiabatic base, the cylinders having an exposed cylinder surface according to different horizontal angle. The cylinder receives heat from a radiating heater which results in a buoyant flow. There are many industrial applications, including refrigeration, ventilation and the cooling of electrical components, for which the present study may be applicable.

Investigation of breached depleted UF{sub 6} cylinders

Energy Technology Data Exchange (ETDEWEB)

DeVan, J.H. [Martin Marietta Energy Systems, Inc., Oak Ridge, TN (United States)

1991-12-31

In June 1990, during a three-site inspection of cylinders being used for long-term storage of solid depleted UF{sub 6}, two 14-ton cylinders at Portsmouth, Ohio, were discovered with holes in the barrel section of the cylinders. An investigation team was immediately formed to determine the cause of the failures and their impact on future storage procedures and to recommend corrective actions. Subsequent investigation showed that the failures most probably resulted from mechanical damage that occurred at the time that the cylinders had been placed in the storage yard. In both cylinders evidence pointed to the impact of a lifting lug of an adjacent cylinder near the front stiffening ring, where deflection of the cylinder could occur only by tearing the cylinder. The impacts appear to have punctured the cylinders and thereby set up corrosion processes that greatly extended the openings in the wall and obliterated the original crack. Fortunately, the reaction products formed by this process were relatively protective and prevented any large-scale loss of uranium. The main factors that precipitated the failures were inadequate spacing between cylinders and deviations in the orientations of lifting lugs from their intended horizontal position. After reviewing the causes and effects of the failures, the team`s principal recommendation for remedial action concerned improved cylinder handling and inspection procedures. Design modifications and supplementary mechanical tests were also recommended to improve the cylinder containment integrity during the stacking operation.

Radiation levels on empty cylinders containing heel material

Energy Technology Data Exchange (ETDEWEB)

Shockley, C.W. [Martin Marietta Energy Systems, Inc., Paducah, KY (United States)

1991-12-31

Empty UF{sub 6} cylinders containing heel material were found to emit radiation levels in excess of 200 mr/hr, the maximum amount stated in ORO-651. The radiation levels were as high as 335 mr/hr for thick wall (48X and 48Y) cylinders and 1050 mr/hr for thin wall (48G and 48H) cylinders. The high readings were found only on the bottom of the cylinders. These radiation levels exceeded the maximum levels established in DOT 49 CFR, Part 173.441 for shipment of cylinders. Holding periods of four weeks for thick-wall cylinders and ten weeks for thin-wall cylinders were established to allow the radiation levels to decay prior to shipment.

Use and generation of floor response spectra

International Nuclear Information System (INIS)

Ordonez Villalobos, A.

1983-01-01

One of the main objectives of the dynamic analysis of the structures of a nuclear power plant is the determination of the dynamic input that these structures transmit to the equipment and substructures they support, usually given as Floor Response Spectra (FRS). A close collaboration and feedback between the different groups that use and develop the FRS, is considered to be a very important factor in order to adapt the scope and content of the FRS to the precision required for a proper analysis or testing of the equipment; not only for the action of simple events but also for multiple combined actions. These aspects should be evaluated not only in the final stages of qualification of the equipment users schedules do not coincide with the schedules of the analysis group that develops the FRS. Different mechanisms of interchange of information and colaboration are suggested in order to optimize the availability, use and production of FRS. In the aspect of FRS generation, different procedures are reviewed including the direct procedures, not only for FRS but also for secondary FRS that are needed for the evaluation of equipment supported on other equipment or subsystems. It is concluded that in many cases, the direct procedures can be developed economically with the advantage that is easy to take into account the variability not only of the transfer function (including damping, stiffness and modal mass ratio). Different probabilities of excedence levels can be stabilized in order to obtain a more realistic dynamic response of the equipment. These last aspects can contribute to a more flexible procedure for the availability and generation of the FRS. (orig./HP)

Stress analysis of cylinder to cylinder intersections

International Nuclear Information System (INIS)

Revesz, Z.

1983-01-01

Cylinder to cylinder intersections have numerous applications in the power industry from different piping junctions to pressure vessel nozzles. A specific purpose computer program has been installed at the author's establishment for finite element analysis of such geometries. Some of the experiences are presented giving a short overview of the analysis of unreinforced man-holes, demonstrating how a more economical design has been verified by analysis. The program installed has linear-elastic and elasto-plastic capabilities. Further, it is prepared for heat transfer analysis with subsequent thermal stress computation. An efficient pre- and post-processor has also been installed and enhanced by the author. The software used is at its present stage capable for problem definition with input data such as outside/ inside diameters, length and number of subdivisions. Similarly simple is the load definition and the graphic representation of the full output. (author)

European good practice in composite floor construction

NARCIS (Netherlands)

Brekelmans, J.W.P.M.; Daniels, B.J.; Stark, J.W.B.; Darwin, David; Buckner, C.D.

1992-01-01

Previous European experience, research and design for composite slabs with profiled steel decking are discussed. Present efforts to harmonize composite slab design and good construction practice are presented. Future European developments, for the next five years, are postulated.

Stabilization of flow past a rounded cylinder

Science.gov (United States)

Samtaney, Ravi; Zhang, Wei

2016-11-01

We perform global linear stability analysis on low-Re flow past a rounded cylinder. The cylinder corners are rounded with a radius R, normalized as R+ = R / D where D is the cylinder diameter, and its effect on the flow stability characteristics is investigated. We compute the critical Reynolds number (Recr) for the onset of first instability, and quantify the perturbation growth rate for the super-critical flows. It is found that the flow can be stabilized by partially rounding the cylinder. Compared with the square and circular cylinders, the partially rounded cylinder has a higher Recr , attaining a maximum at around R+ = 0 . 30 , and the perturbation growth rate of the super-critical flows is reduced for Re R+ -> 0 . 00), while only the near-wake backflow is crucial for circular-like cylinders (R+ -> 0 . 50). The stability analysis results are also verified with those of the direct simulations and very good agreement is achieved. Supported by the KAUST Office of Competitive Research Funds under Award No. URF/1/1394-01. The supercomputer Shaheen at KAUST was utilized for the simulations.

Overseas shipments of 48Y cylinders

Energy Technology Data Exchange (ETDEWEB)

Tanaka, R.T.; Furlan, A.S. [Cameco Corp., Port Hope, Ontario (Canada)

1991-12-31

This paper describes experiences with two incidents of overseas shipments of uranium hexafluoride (UF{sub 6}) cylinders. The first incident involved nine empty UF{sub 6} cylinders in enclosed sea containers. Three UF{sub 6} cylinders broke free from their tie-downs and damaged and contaminated several sea containers. This paper describes briefly how decontamination was carried out. The second incident involved a shipment of 14 full UF{sub 6} cylinders. Although the incident did not cause an accident, the potential hazard was significant. The investigation of the cause of the near accident is recounted. Recommendations to alleviate future similar incidents for both cases are presented.

Reaerosolization of Spores from Flooring Surfaces To Assess the Risk of Dissemination and Transmission of Infections.

Science.gov (United States)

Paton, Susan; Thompson, Katy-Anne; Parks, Simon R; Bennett, Allan M

2015-08-01

The aim of this study was to quantify reaerosolization of microorganisms caused by walking on contaminated flooring to assess the risk to individuals accessing areas contaminated with pathogenic organisms, for example, spores of Bacillus anthracis. Industrial carpet and polyvinyl chloride (PVC) floor coverings were contaminated with aerosolized spores of Bacillus atrophaeus by using an artist airbrush to produce deposition of ∼10(3) to 10(4) CFU · cm(-2). Microbiological air samplers were used to quantify the particle size distribution of the aerosol generated when a person walked over the floorings in an environmental chamber. Results were expressed as reaerosolization factors (percent per square centimeter per liter), to represent the ratio of air concentration to surface concentration generated. Walking on carpet generated a statistically significantly higher reaerosolization factor value than did walking on PVC (t = 20.42; P flooring in order to inform the choice of appropriate respiratory protective equipment and may aid in the selection of the most suitable flooring types for use in health care environments, to reduce aerosol transmission in the event of contamination. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

A methodology to identify the intake charge cylinder-to-cylinder distribution in turbocharged direct injection Diesel engines

Science.gov (United States)

Luján, José M.; Galindo, José; Serrano, José R.; Pla, Benjamín

2008-06-01

Exhaust gas recirculation (EGR) is currently the most important NOx emission control system. During the last few years the EGR rate has increased progressively as pollutant emission regulations have become more restrictive. High EGR rate levels have given the effect of the unsuitable EGR and air distribution between cylinders away, which causes undesirable engine behavior. In this sense, the study of the EGR distribution between cylinders achieves high importance. However, despite the fact that the EGR is continuously under study, not many studies have been undertaken to approach its distribution between cylinders. In concordance with the aspects outlined before, the aim of this paper is to propose a methodology that permits us to identify the EGR cylinder-to-cylinder dispersion in a commercial engine. In order to achieve this objective, experimental tests have been combined with both one-dimensional and three-dimensional fluid dynamic models.

Robust cylinder pressure estimation in heavy-duty diesel engines

NARCIS (Netherlands)

Kulah, S.; Forrai, A.; Rentmeester, F.; Donkers, T.; Willems, F.P.T.

2017-01-01

The robustness of a new single-cylinder pressure sensor concept is experimentally demonstrated on a six-cylinder heavy-duty diesel engine. Using a single-cylinder pressure sensor and a crank angle sensor, this single-cylinder pressure sensor concept estimates the in-cylinder pressure traces in the

Improvement of the Magnetic Shielding Effects by the Superposition of a Multi-Layered Ferromagnetic Cylinder over an HTS Cylinder: Relationship Between the Shielding Effects and the Layer Number of the Ferromagnetic Cylinder

International Nuclear Information System (INIS)

Yasui, K; Tarui, Y; Itoh, M

2006-01-01

The idealized magnetic shielded vessel can be realized by making use of a high-critical temperature superconductor (HTS). It is difficult for practical applications, however, to fabricate a shielding vessel that has a high value of the maximum shielded magnetic flux density B s0 . The present authors have improved the value of B s0 for the Bi-Pb-Sr-Ca-Cu-O (BPSCCO) cylinder used as the shielding vessel, by the superposition of a four-layered softiron cylinder over the BPSCCO cylinder, termed the four-layered superimposed cylinder. The B s4 value of 610 x 10 -4 T for the four-layered superimposed cylinder, is found to be about 4 times larger than that of a single-BPSCCO cylinder, and is theoretically analyzed by use of a new analysis method. The experimental values of the maximum shielded magnetic flux density B sn of n-layered superimposed cylinders are found to agree well with those of the theoretical analysis. Experimental results revealed several characteristics of the magnetic shielding within the n-layered superimposed cylinders. Also discussed is the new analysis method for the relationship between the n and B sn

Flooring-systems and their interaction with usage of the floor

DEFF Research Database (Denmark)

Pedersen, Lars; Frier, Christian; Andersen, Lars Vabbersgaard

2017-01-01

Some flooring-system designs might be sensitive to their vibrational performance, as there might be the risk that serviceability-limit-state problems may be encountered. For evaluating the vibrational performance of the flooring-system at the design stage, decisions need to be made by the enginee...

Aerodynamic loading on a cylinder behind an airfoil

Energy Technology Data Exchange (ETDEWEB)

Zhang, H.J.; Huang, L.; Zhou, Y. [Hong Kong Polytechnic University, Department of Mechanical Engineering, Kowloon (Hong Kong)

2005-05-01

The interaction between the wake of a rotor blade and a downstream cylinder holds the key to the understanding and control of electronic cooling fan noise. In this paper, the aerodynamic characteristics of a circular cylinder are experimentally studied in the presence of an upstream NACA 4412 airfoil for the cylinder-diameter-based Reynolds numbers of Re{sub d}=2,100-20,000, and the airfoil chord-length-based Reynolds numbers of Re{sub c}=14,700-140,000. Lift and drag fluctuations on the cylinder, and the longitudinal velocity fluctuations of the flow behind the cylinder were measured simultaneously using a load cell and two hot wires, respectively. Data analysis shows that unsteady forces on the cylinder increase significantly in the presence of the airfoil wake. The dependence of the forces on two parameters is investigated, that is, the lateral distance (T) between the airfoil and the cylinder, and the Reynolds number. The forces decline quickly as Tincreases. For Re{sub c}<60,000, the vortices shed from the upstream airfoil make a major contribution to the unsteady forces on the cylinder compared to the vortex shedding from the cylinder itself. For Re{sub c}>60,000, no vortices are generated from the airfoil, and the fluctuating forces on the cylinder are caused by its own vortex shedding. (orig.)

Inner cylinder of the CMS vacuum tank.

CERN Multimedia

Patrice Loïez

2002-01-01

The vacuum tank of the CMS magnet system consists of inner and outer stainless-steel cylinders and houses the superconducting coil. The inner cylinder contains all the barrel sub-detectors, which it supports via a system of horizontal rails. The cylinder is pictured here in the vertical position on a yellow platform mounted on the ferris-wheel support structure. This will allow it to be pivoted and inserted into the outer cylinder already attached to the innermost ring of the barrel yoke.

UF{sub 6} pressure excursions during cylinder heating

Energy Technology Data Exchange (ETDEWEB)

Brown, P.G. [Martin Marietta Energy Systems, Inc., Paducah, KY (United States)

1991-12-31

As liquid UF{sub 6} inside a cylinder changes from a liquid to a solid, it forms a porous solid which occupies approximately the same volume as that of the liquid before cooling. Simultaneously as the liquid cools, UF{sub 6} vapor in the cylinder ullage above the liquid desublimes on the upper region of the inner cylinder wall. This solid is a dense, glass-like material which can accumulate to a significant thickness. The thickness of the solid coating on the upper cylinder wall and directly behind the cylinder valve area will vary depending on the conditions during the cooling stage. The amount of time lapsed between UF{sub 6} solidification and UF{sub 6} liquefaction can also affect the UF{sub 6} coating. This is due to the daily ambient heat cycle causing the coating to sublime from the cylinder wall to cooler areas, thus decreasing the thickness. Structural weakening of the dense UF{sub 6} layer also occurs due to cylinder transport vibration and thermal expansion. During cylinder heating, the UF{sub 6} nearest the cylinder wall will liquefy first. As the solid coating behind the cylinder valve begins to liquefy, it results in increased pressure depending upon the available volume for expansion. At the Paducah Gaseous Diffusion Plant (PGDP) during the liquefaction of the UF{sub 6} in cylinders in the UF{sub 6} feed and sampling autoclaves, this pressure increase has resulted in the activation of the systems rupture discs which are rated at 100 pounds per square inch differential.

Numerical Study of Shock-Cylinder Banks Interactions

International Nuclear Information System (INIS)

Wang, S.P.; Anderson, M.H.; Oakley, J.G.; Bonazza, R.

2003-01-01

A numerical parametric study of shock-cylinder banks interactions is presented using a high resolution Euler solver. Staggered cylinder banks of five rows are chosen with the purpose of modeling IFE reactor cooling tube banks. The effect of the aspect ratio of the intercylinder pitch to the distance between successive cylinder rows on the vertical pressure forces acting on the cylinders with different geometries is investigated. Preliminary results show that the largest vertical force develops on the cylinders of the second or third row. This peak pressure force increases with decreasing values of the aspect ratio. It is shown that an increasing second force peak also appears on the successive rows, starting with the second one, with decreasing aspect ratio. It is also observed that the force on the last-row cylinders basically decreases to the level of that on the first row. The results are useful for the optimal design of the cooling tubes system of IFE reactors

Theoretical and experimental stress analyses of ORNL thin-shell cylinder-to-cylinder model 3

International Nuclear Information System (INIS)

Gwaltney, R.C.; Bolt, S.E.; Corum, J.M.; Bryson, J.W.

1975-06-01

The third in a series of four thin-shell cylinder-to-cylinder models was tested, and the experimentally determined elastic stress distributions were compared with theoretical predictions obtained from a thin-shell finite-element analysis. The models are idealized thin-shell structures consisting of two circular cylindrical shells that intersect at right angles. There are no transitions, reinforcements, or fillets in the junction region. This series of model tests serves two basic purposes: the experimental data provide design information directly applicable to nozzles in cylindrical vessels; and the idealized models provide test results for use in developing and evaluating theoretical analyses applicable to nozzles in cylindrical vessels and to thin piping tees. The cylinder of model 3 had a 10 in. OD and the nozzle had a 1.29 in. OD, giving a d 0 /D 0 ratio of 0.129. The OD/thickness ratios for the cylinder and the nozzle were 50 and 7.68 respectively. Thirteen separate loading cases were analyzed. In each, one end of the cylinder was rigidly held. In addition to an internal pressure loading, three mutually perpendicular force components and three mutually perpendicular moment components were individually applied at the free end of the cylinder and at the end of the nozzle. The experimental stress distributions for all the loadings were obtained using 158 three-gage strain rosettes located on the inner and outer surfaces. The loading cases were also analyzed theoretically using a finite-element shell analysis developed at the University of California, Berkeley. The analysis used flat-plate elements and considered five degrees of freedom per node in the final assembled equations. The comparisons between theory and experiment show reasonably good agreement for this model. (U.S.)

Theoretical and experimental stress analyses of ORNL thin-shell cylinder-to-cylinder model 4

International Nuclear Information System (INIS)

Gwaltney, R.C.; Bolt, S.E.; Bryson, J.W.

1975-06-01

The last in a series of four thin-shell cylinder-to-cylinder models was tested, and the experimentally determined elastic stress distributions were compared with theoretical predictions obtained from a thin-shell finite-element analysis. The models in the series are idealized thin-shell structures consisting of two circular cylindrical shells that intersect at right angles. There are no transitions, reinforcements, or fillets in the junction region. This series of model tests serves two basic purposes: (1) the experimental data provide design information directly applicable to nozzles in cylindrical vessels, and (2) the idealized models provide test results for use in developing and evaluating theoretical analyses applicable to nozzles in cylindrical vessels and to thin piping tees. The cylinder of model 4 had an outside diameter of 10 in., and the nozzle had an outside diameter of 1.29 in., giving a d 0 /D 0 ratio of 0.129. The OD/thickness ratios were 50 and 20.2 for the cylinder and nozzle respectively. Thirteen separate loading cases were analyzed. For each loading condition one end of the cylinder was rigidly held. In addition to an internal pressure loading, three mutually perpendicular force components and three mutually perpendicular moment components were individually applied at the free end of the cylinder and at the end of the nozzle. The experimental stress distributions for each of the 13 loadings were obtained using 157 three-gage strain rosettes located on the inner and outer surfaces. Each of the 13 loading cases was also analyzed theoretically using a finite-element shell analysis developed at the University of California, Berkeley. The analysis used flat-plate elements and considered five degrees of freedom per node in the final assembled equations. The comparisons between theory and experiment show reasonably good agreement for this model. (U.S.)

Cracking investigation of Monju emergency generator C unit cylinder liner. Cylinder liner soundness confirmation by a fall cause of the materials strength of the cylinder liner and the supersonic wave speed

International Nuclear Information System (INIS)

Kobayashi, Takanori; Sakon, Miyoji; Takada, Osamu; Hatori, Masakazu; Sakamoto, Tsutomu; Sato, Toshiyuki; Kazama, Akihito; Ishizawa, Yoshihiro; Igawa, Katsuhisa; Nakae, Hideo

2012-02-01

I confirmed a leak of the effluent gas from cylinder part during a load examination after the check of the emergency generator C unit on December 28, 2010 of the facilities check average and confirmed crack in No.8 cylinder liner part. As a result, because it was not performed oil pressure management properly without attaching an oil pressure gauge when I removed cylinder liner about the cause, crack occurred by having been able to write excessive stress for the cylinder liner and reached damage. By a process of this investigation, a fall of the materials strength of some cylinder liner was confirmed, but because a lead ingredient got mixed with materials by a casting process at the time of the production of the cylinder liner, as for this, Widmannstaetten graphite occurred, and it became clear that materials strength fell. In addition, I performed inspection by the supersonic wave velocity measurement as technique to distinguish this Widmannstaetten graphite easily and confirmed that I was effective. Because this report was the knowledge that there were little inspection contents which modified soundness confirmation technique of the cylinder liner with the possibility of materials strength fall of the cylinder liner by the Widmannstaetten graphite outbreak and the mixture of lead for a report example in the field of cast iron, I gathered it in this report. (author)

Targeted energy transfer in laminar vortex-induced vibration of a sprung cylinder with a nonlinear dissipative rotator

Science.gov (United States)

Blanchard, Antoine; Bergman, Lawrence A.; Vakakis, Alexander F.

2017-07-01

We computationally investigate the dynamics of a linearly-sprung circular cylinder immersed in an incompressible flow and undergoing transverse vortex-induced vibration (VIV), to which is attached a rotational nonlinear energy sink (NES) consisting of a mass that freely rotates at constant radius about the cylinder axis, and whose motion is restrained by a rotational linear viscous damper. The inertial coupling between the rotational motion of the attached mass and the rectilinear motion of the cylinder is ;essentially nonlinear;, which, in conjunction with dissipation, allows for one-way, nearly irreversible targeted energy transfer (TET) from the oscillating cylinder to the nonlinear dissipative attachment. At the intermediate Reynolds number Re = 100, the NES-equipped sprung cylinder undergoes repetitive cycles of slowly decaying oscillations punctuated by intervals of chaotic instabilities. During the slowly decaying portion of each cycle, the dynamics of the cylinder is regular and, for large enough values of the ratio ε of the NES mass to the total mass (i.e., NES mass plus cylinder mass), can lead to significant vortex street elongation with partial stabilization of the wake. As ε approaches zero, no such vortex elongation is observed and the wake patterns appear similar to that for a sprung cylinder with no NES. We apply proper orthogonal decomposition (POD) to the velocity flow field during a slowly decaying portion of the solution and show that, in situations where vortex elongation occurs, the NES, though not in direct contact with the surrounding fluid, has a drastic effect on the underlying flow structures, imparting significant and continuous passive redistribution of energy among POD modes. We construct a POD-based reduced-order model for the lift coefficient to characterize energy transactions between the fluid and the cylinder throughout the slowly decaying cycle. We introduce a quantitative signed measure of the work done by the fluid on the

Supporting shop floor intelligence

DEFF Research Database (Denmark)

Carstensen, Peter; Schmidt, Kjeld; Wiil, Uffe Kock

1999-01-01

Many manufacturing enterprises are now trying to introduce various forms of flexible work organizations on the shop floor. However, existing computer-based production planning and control systems pose severe obstacles for autonomous working groups and other kinds of shop floor control to become r......-to-day production planning by supporting intelligent and responsible workers in their situated coordination activities on the shop floor....

Lower bound buckling loads for design of laminate composite cylinders

Science.gov (United States)

Croll, James G. A.; Wang, Hongtao

2017-01-01

Over a period of more than 45 years, an extensive research program has allowed a series of very simple propositions, relating to the safe design of shells experiencing imperfection sensitive buckling, to be recast in the form of a series of lemmas. These are briefly summarized and their practical use is illustrated in relation to the prediction of safe lower bounds to the imperfection sensitive buckling of axially loaded, fiber reinforced polymeric, laminated cylinders. With a fundamental aspect of the approach, sometimes referred to as the reduced stiffness method, being the delineation of the various shell membrane and bending stiffness (or perhaps more appropriately energy) components contributing to the buckling resistance, the method will be shown to also provide a powerful way of making rational design decisions to optimize the use of fiber reinforcement.

Approximation of Surfaces by Cylinders

DEFF Research Database (Denmark)

Randrup, Thomas

1998-01-01

We present a new method for approximation of a given surface by a cylinder surface. It is a constructive geometric method, leading to a monorail representation of the cylinder surface. By use of a weighted Gaussian image of the given surface, we determine a projection plane. In the orthogonal...

UF{sub 6} cylinder fire test

Energy Technology Data Exchange (ETDEWEB)

Park, S.H. [Oak Ridge K-25 Site, Oak Ridge, TN (United States)

1991-12-31

With the increasing number of nuclear reactors for power generation, there is a comparable increase in the amount of UF{sub 6} being transported. Likewise, the probability of having an accident involving UF{sub 6}-filled cylinders also increases. Accident scenarios which have been difficult to assess are those involving a filled UF{sub 6} cylinder subjected to fire. A study is underway at the Oak Ridge K-25 Site, as part of the US DOE Enrichment Program, to provide empirical data and a computer model that can be used to evaluate various cylinder-in-fire scenarios. It is expected that the results will provide information leading to better handling of possible fire accidents as well as show whether changes should be made to provide different physical protection during shipment. The computer model being developed will be capable of predicting the rupture of various cylinder sizes and designs as well as the amount of UF{sub 6}, its distribution in the cylinder, and the conditions of the fire.

TECHNO-ECONOMIC ANALYSIS IN A SUPERSTRUCTURE OF A MULTIPLE FLOORS BUILDING (THREE, FIVE, SEVEN AND NINE FLOORS IN REINFORCED CONCRETE AND RIBBED SLABS WITH RECTANGULAR FORM AND DIFFERENT COMPRESSIVE STRENGTH VALUES

Directory of Open Access Journals (Sweden)

E. F. S. Moraes

2017-12-01

Full Text Available Adapting “fck" values between 25 MPa to 40 MPa, in three, five, seven and nine floor buildings for places under winds of up to 30 m/s, this research calculated the cost and inputs of these variations. The results have as a goal to improve multiple floors building design in reinforced concrete and ribbed slabs, and to contribute to economic gains. The results were analysed in five stages. (I Architectural design definition in a 1:1 proportion, (II structural conception, (III structural design, (IV cost composition and (V techno economic parameters. To sum up, the results showed that lower “fck” has presented more viability to few flooring. In addition, with the increase of floors also the “fck” raised, causing higher cost around 16,54% in the beams and 11,16% in the slabs. Moreover, the pillars showed a saving of 28,89% in the cost, ranging by up to 11,93% in the average thickness and 6,29% in the concrete form expenditure per m³. Therefore, the research showed an economic achievement of 5,14% in the overall cost between the number of floor.

Turbulence and heat transfer in condensate in drying cylinders at high g-forces. Phase 1; Turbulens och vaermeoeverfoering i kondensat i torkcylindrar vid hoega g-krafter. Fas 1

Energy Technology Data Exchange (ETDEWEB)

Stenstroem, Stig; Ingvarsson, David [Lund Inst. of Tech. (Sweden). Dept. of Chemical Engineering

2005-09-01

over 40g, the condensate layer is stagnant in both smooth and cylinders equipped with spoiler bars. For new machines improved heat transfer can be accomplished by providing the cylinders with axial grooves while for existing cylinders the inner surface of the cylinder should be provided with flanges. Assuming that all the condensate is collected in the grooves, the calculations show that the drying capacity for a cylinder with grooves could be increased with up to 60 % compared with a smooth cylinder with 1 mm of condensate and with 22% compared with a cylinder equipped with spoiler bars. Recommendations for improved heat transfer have been presented for both new and existing machines. New data for the condensate flow at high centrifugal forces has been presented in the project.

Three-dimensional vortex flow near the endwall of a short cylinder in crossflow: Uniform-diameter circular cylinder

International Nuclear Information System (INIS)

Chen, S.B.; Sanitjai, S.; Ghosh, K.; Goldstein, R.J.

2012-01-01

Flow characteristics, around a short uniform-diameter circular cylinder in crossflow, are investigated experimentally. Extensive flow visualization using oil-lampblack and smoke-wire methods have been performed. Near-wake velocity measurements have been performed using a hotwire anemometer. Complex secondary flows are observed on and around the cylinder in crossflow. Multiple vortices are observed in the horseshoe vortex system near the cylinder–endwall junction. Based on this flow visualization and local mass transfer measurement results, a six-vortex secondary flow model has been proposed. - Highlights: ► Flow visualizations and velocity measurements for a short circular cylinder. ► Six vortices in the horseshoe vortex system upstream of the base of the cylinder. ► Cross-stream turbulence intensity profiles show a similarity in their shape.

Prediction of External Corrosion for Steel Cylinders--2004 Report

International Nuclear Information System (INIS)

Schmoyer, RLS

2004-01-01

Depleted uranium hexafluoride (UF 6 ) is stored in over 60,000 steel cylinders at the East Tennessee Technology Park (ETTP) in Oak Ridge, Tennessee, at the Paducah Gaseous Diffusion Plant (PGDP) in Paducah, Kentucky, and at the Portsmouth Gaseous Diffusion Plant (PORTS) in Portsmouth, Ohio. The cylinders range in age from 4 to 53 years. Although when new the cylinders had wall thicknesses specified to within manufacturing tolerances, over the years corrosion has reduced their actual wall thicknesses. The UF 6 Cylinder Project is managed by the United States Department of Energy (DOE) to safely maintain the UF 6 and the cylinders containing it. This report documents activities that address UF 6 Cylinder Project requirements and actions involving forecasting cylinder wall thicknesses. These requirements are delineated in the System Requirements Document (LMES 1997a), and the actions needed to fulfill them are specified in the System Engineering Management Plan (LMES 1997b). The report documents cylinder wall thickness projections based on models fit to ultrasonic thickness (UT) measurement data. UT data is collected at various locations on randomly sampled cylinders. For each cylinder sampled, the minimum UT measurement approximates the actual minimum thickness of the cylinder. Projections of numbers of cylinders expected to fail various thickness criteria are computed from corrosion models relating minimum wall thickness to cylinder age, initial thickness estimates, and cylinder subpopulations defined in terms of plant site, yard, top or bottom storage positions, nominal thickness, etc. In this report, UT data collected during FY03 is combined with UT data collected in earlier years (FY94-FY02), and all of the data is inventoried chronologically and by various subpopulations. The UT data is used to fit models of maximum pit depth and minimum thickness, and the fitted models are used to extrapolate minimum thickness estimates into the future and in turn to compute

Investigation of Concrete Floor Vibration Using Heel-Drop Test

Science.gov (United States)

Azaman, N. A. Mohd; Ghafar, N. H. Abd; Azhar, A. F.; Fauzi, A. A.; Ismail, H. A.; Syed Idrus, S. S.; Mokhjar, S. S.; Hamid, F. F. Abd

2018-04-01

In recent years, there is an increased in floor vibration problems of structures like residential and commercial building. Vibration is defined as a serviceability issue related to the comfort of the occupant or damage equipment. Human activities are the main source of vibration in the building and it could affect the human comfort and annoyance of residents in the building when the vibration exceed the recommend level. A new building, Madrasah Tahfiz located at Yong Peng have vibration problem when load subjected on the first floor of the building. However, the limitation of vibration occurs on building is unknown. Therefore, testing is needed to determine the vibration behaviour (frequency, damping ratio and mode shape) of the building. Heel-drop with pace 2Hz was used in field measurement to obtain the vibration response. Since, the heel-drop test results would vary in light of person performance, test are carried out three time to reduce uncertainty. Natural frequency from Frequency Response Function analysis (FRF) is 17.4Hz, 16.8, 17.4Hz respectively for each test.

Technical Interoperability for Machine Connectivity on the Shop Floor

Directory of Open Access Journals (Sweden)

Magnus Åkerman

2018-06-01

Full Text Available This paper presents a generic technical solution that can increase Industry 4.0 maturity by collecting data from sensors and control systems on the shop floor. Within the research project “5G-Enabled Manufacturing”, an LTE (Long-Term Evolution network with 5G technologies was deployed on the shop floor to enable fast and scalable connectivity. This network was used to connect a grinding machine to a remote private cloud where data was stored and streamed to a data analytics center. This enabled visibility and transparency of the production data, which is the basis for Industry 4.0 and smart manufacturing. The solution is described with a focus on high-level communication technologies above wireless communication standards. These technologies are discussed regarding technical interoperability, focusing on the system layout, communication standards, and open systems. From the discussion, it can be derived that generic solutions such as this are possible, but manufacturing end-users must expand and further internalize knowledge of future information and communication technologies to reduce their dependency on equipment and technology providers.

Exact solution for stresses/displacements in a multilayered hollow cylinder under thermo-mechanical loading

International Nuclear Information System (INIS)

Yeo, W.H.; Purbolaksono, J.; Aliabadi, M.H.; Ramesh, S.; Liew, H.L.

2017-01-01

In this study, a new analytical solution by the recursive method for evaluating stresses/displacements in multilayered hollow cylinder under thermo-mechanical loading was developed. The results for temperature distribution, displacements and stresses obtained by using the proposed solution were shown to be in good agreement with the FEM results. The proposed analytical solution was also found to produce more accurate results than those by the analytical solution reported in literature. - Highlights: • A new analytical solution for evaluating stresses in multilayered hollow cylinder under thermo-mechanical loading. • A simple computational procedure using a recursive method. • A promising technique for evaluating the operating axial and hoop stresses in pressurized composite vessels.

A competing risk model for the reliability of cylinder liners in marine Diesel engines

Energy Technology Data Exchange (ETDEWEB)

Bocchetti, D. [Grimaldi Group, Naples (Italy); Giorgio, M. [Department of Aerospace and Mechanical Engineering, Second University of Naples, Aversa (Italy); Guida, M. [Department of Information Engineering and Electrical Engineering, University of Salerno, Fisciano (Italy); Pulcini, G. [Istituto Motori, National Research Council-CNR, Naples (Italy)], E-mail: g.pulcini@im.cnr.it

2009-08-15

In this paper, a competing risk model is proposed to describe the reliability of the cylinder liners of a marine Diesel engine. Cylinder liners presents two dominant failure modes: wear degradation and thermal cracking. The wear process is described through a stochastic process, whereas the failure time due to the thermal cracking is described by the Weibull distribution. The use of the proposed model allows performing goodness-of-fit test and parameters estimation on the basis of both wear and failure data. Moreover, it enables reliability estimates of the state of the liners to be obtained and the hierarchy of the failure mechanisms to be determined for any given age and wear level of the liner. The model has been applied to a real data set: 33 cylinder liners of Sulzer RTA 58 engines, which equip twin ships of the Grimaldi Group. Estimates of the liner reliability and of other quantities of interest under the competing risk model are obtained, as well as the conditional failure probability and mean residual lifetime, given the survival age and the accumulated wear. Furthermore, the model has been used to estimate the probability that a liner fails due to one of the failure modes when both of these modes act.

Optimization and improvement of Halbach cylinder design

DEFF Research Database (Denmark)

Bjørk, Rasmus; Bahl, Christian Robert Haffenden; Smith, Anders

2008-01-01

possible volume of magnets with a given mean flux density in the cylinder bore. The volume of the cylinder bore could also be significantly increased by only slightly increasing the volume of the magnets, for a fixed mean flux density. Placing additional blocks of magnets on the end faces of the Halbach...... that this parameter was optimal for long Halbach cylinders with small rex. Using the previously mentioned additional blocks of magnets can improve the parameter by as much as 15% as well as improve the homogeneity of the field in the cylinder bore. ©2008 American Institute of Physics...

17 CFR 3.11 - Registration of floor brokers and floor traders.

Science.gov (United States)

2010-04-01

... 17 Commodity and Securities Exchanges 1 2010-04-01 2010-04-01 false Registration of floor brokers and floor traders. 3.11 Section 3.11 Commodity and Securities Exchanges COMMODITY FUTURES TRADING... a contract market or registered as a derivatives transaction execution facility by the Commission...

Niobium carbide synthesis by solid-gas reaction using a rotating cylinder reactor

International Nuclear Information System (INIS)

Fontes, F.A.O.; Gomes, K.K.P.; Oliveira, S.A.; Souza, C.P.; Sousa, J.F.; Rio Grande do Norte Univ., Natal, RN

2004-01-01

A rotating cylinder reactor was designed for the synthesis of niobium carbide powders at 1173 K. Niobium carbide, NbC, was prepared by carbothermal reduction starting from commercial niobium pentoxide powders. The reactor was heated using a custom-made, two-part, hinged, electric furnace with programmable temperature control. The design and operational details of the reactor are presented. The longitudinal temperature gradient inside the reactor was determined. Total reaction time was monitored by a gas chromatograph equipped with an FID detector for determination of methane concentrations. The results show that time of reaction depended on rotation speed. NbC was also prepared in a static-bed alumina reactor using the same conditions as in the previous case. The niobium carbide powders were characterized by X-ray diffraction and compared with commercially available products. Morphological, particle size distribution and surface area analyses were obtained using SEM, LDPS and BET, respectively. Therefore, the present study offers a significant technological contribution to the synthesis of NbC powders in a rotating cylinder reactor. (author)

Prediction of External Corrosion for Steel Cylinders--2007 Report

Energy Technology Data Exchange (ETDEWEB)

Schmoyer, Richard L [ORNL

2008-01-01

Depleted uranium hexafluoride (DUF{sub 6}) is stored in over 62,000 containment cylinders at the Paducah Gaseous Diffusion Plant (PGDP) in Paducah, Kentucky, and at the Portsmouth Gaseous Diffusion Plant (PORTS) in Portsmouth, Ohio. Over 4,800 of the cylinders at Portsmouth were recently moved there from the East Tennessee Technology Park (ETTP) in Oak Ridge, Tennessee. The cylinders range in age up to 56 years and come in various models, but most are 48-inch diameter 'thin-wall'(312.5 mil) and 'thick-wall' (625 mil) cylinders and 30-inch diameter '30A' (including '30B') cylinders with 1/2-inch (500 mil) walls. Most of the cylinders are carbon steel, and they are subject to corrosion. The United States Department of Energy (DOE) manages the cylinders to maintain them and the DUF{sub 6} they contain. Cylinder management requirements are specified in the System Requirements Document (LMES 1997a), and the activities to fulfill them are specified in the System Engineering Management Plan (LMES 1997b). This report documents activities that address DUF{sub 6} cylinder management requirements involving measuring and forecasting cylinder wall thicknesses. As part of these activities, ultrasonic thickness (UT) measurements are made on samples of cylinders. For each sampled cylinder, multiple measurements are made in an attempt to find, approximately, the minimum wall thickness. Some cylinders have a skirt, which is an extension of the cylinder wall to protect the head (end) and valve. The head/skirt interface crevice is thought to be particularly vulnerable to corrosion, and for some skirted cylinders, in addition to the main body UT measurements, a separate suite of measurements is also made at the head/skirt interface. The main-body and head/skirt minimum thickness data are used to fit models relating minimum thickness to cylinder age, nominal thicknesses, and cylinder functional groups defined in terms of plant site, storage yard

Cylinder Position Servo Control Based on Fuzzy PID

Directory of Open Access Journals (Sweden)

Shibo Cai

2013-01-01

Full Text Available The arbitrary position control of cylinder has always been the hard challenge in pneumatic system. We try to develop a cylinder position servo control method by combining fuzzy PID with the theoretical model of the proportional valve-controlled cylinder system. The pressure differential equation of cylinder, pressure-flow equation of proportional valve, and moment equilibrium equation of cylinder are established. And the mathematical models of the cylinder driving system are linearized. Then fuzzy PID control algorithm is designed for the cylinder position control, including the detail analysis of fuzzy variables and domain, fuzzy logic rules, and defuzzification. The stability of the proposed fuzzy PID controller is theoretically proved according to the small gain theorem. Experiments for targets position of 250 mm, 300 mm, and 350 mm were done and the results showed that the absolute error of the position control is less than 0.25 mm. And comparative experiment between fuzzy PID and classical PID verified the advantage of the proposed algorithm.

Breached cylinder incident at the Portsmouth gaseous diffusion plant

Energy Technology Data Exchange (ETDEWEB)

Boelens, R.A. [Martin Marietta Energy Systems, Inc., Piketon, OH (United States)

1991-12-31

On June 16, 1990, during an inspection of valves on partially depleted product storage cylinders, a 14-ton partially depleted product cylinder was discovered breached. The cylinder had been placed in long-term storage in 1977 on the top row of Portsmouth`s (two rows high) storage area. The breach was observed when an inspector noticed a pile of green material along side of the cylinder. The breach was estimated to be approximately 8- inches wide and 16-inches long, and ran under the first stiffening ring of the cylinder. During the continuing inspection of the storage area, a second 14-ton product cylinder was discovered breached. This cylinder was stacked on the bottom row in the storage area in 1986. This breach was also located adjacent to a stiffening ring. This paper will discuss the contributing factors of the breaching of the cylinders, the immediate response, subsequent actions in support of the investigation, and corrective actions.

Prediction of External Corrosion for Steel Cylinders--2004 Report

Energy Technology Data Exchange (ETDEWEB)

Schmoyer, RLS

2004-07-07

Depleted uranium hexafluoride (UF{sub 6}) is stored in over 60,000 steel cylinders at the East Tennessee Technology Park (ETTP) in Oak Ridge, Tennessee, at the Paducah Gaseous Diffusion Plant (PGDP) in Paducah, Kentucky, and at the Portsmouth Gaseous Diffusion Plant (PORTS) in Portsmouth, Ohio. The cylinders range in age from 4 to 53 years. Although when new the cylinders had wall thicknesses specified to within manufacturing tolerances, over the years corrosion has reduced their actual wall thicknesses. The UF{sub 6} Cylinder Project is managed by the United States Department of Energy (DOE) to safely maintain the UF{sub 6} and the cylinders containing it. This report documents activities that address UF{sub 6} Cylinder Project requirements and actions involving forecasting cylinder wall thicknesses. These requirements are delineated in the System Requirements Document (LMES 1997a), and the actions needed to fulfill them are specified in the System Engineering Management Plan (LMES 1997b). The report documents cylinder wall thickness projections based on models fit to ultrasonic thickness (UT) measurement data. UT data is collected at various locations on randomly sampled cylinders. For each cylinder sampled, the minimum UT measurement approximates the actual minimum thickness of the cylinder. Projections of numbers of cylinders expected to fail various thickness criteria are computed from corrosion models relating minimum wall thickness to cylinder age, initial thickness estimates, and cylinder subpopulations defined in terms of plant site, yard, top or bottom storage positions, nominal thickness, etc. In this report, UT data collected during FY03 is combined with UT data collected in earlier years (FY94-FY02), and all of the data is inventoried chronologically and by various subpopulations. The UT data is used to fit models of maximum pit depth and minimum thickness, and the fitted models are used to extrapolate minimum thickness estimates into the future and in

Floor cooler for floor trough of a nuclear reactor

International Nuclear Information System (INIS)

Friedrich, H.J.

1985-01-01

Cooling pipes are situated below the floor trough of a BWR, which are connected to the annular distribution or collection pipes. The distribution and collection pipes are connected by parallel hairpin pipes with involute shape to the centre of the floor trough. These hairpin pipes are situated in a lower plane than the annular distribution pipe to the centre and in a higher plane from the centre to the outer annular collector pipe. (orig./HP) [de

Optimized Dose Distribution of Gammamed Plus Vaginal Cylinders

International Nuclear Information System (INIS)

Supe, Sanjay S.; Bijina, T.K.; Varatharaj, C.; Shwetha, B.; Arunkumar, T.; Sathiyan, S.; Ganesh, K.M.; Ravikumar, M.

2009-01-01

Endometrial carcinoma is the most common malignancy arising in the female genital tract. Intracavitary vaginal cuff irradiation may be given alone or with external beam irradiation in patients determined to be at risk for locoregional recurrence. Vaginal cylinders are often used to deliver a brachytherapy dose to the vaginal apex and upper vagina or the entire vaginal surface in the management of postoperative endometrial cancer or cervical cancer. The dose distributions of HDR vaginal cylinders must be evaluated carefully, so that clinical experiences with LDR techniques can be used in guiding optimal use of HDR techniques. The aim of this study was to optimize dose distribution for Gammamed plus vaginal cylinders. Placement of dose optimization points was evaluated for its effect on optimized dose distributions. Two different dose optimization point models were used in this study, namely non-apex (dose optimization points only on periphery of cylinder) and apex (dose optimization points on periphery and along the curvature including the apex points). Thirteen dwell positions were used for the HDR dosimetry to obtain a 6-cm active length. Thus 13 optimization points were available at the periphery of the cylinder. The coordinates of the points along the curvature depended on the cylinder diameters and were chosen for each cylinder so that four points were distributed evenly in the curvature portion of the cylinder. Diameter of vaginal cylinders varied from 2.0 to 4.0 cm. Iterative optimization routine was utilized for all optimizations. The effects of various optimization routines (iterative, geometric, equal times) was studied for the 3.0-cm diameter vaginal cylinder. The effect of source travel step size on the optimized dose distributions for vaginal cylinders was also evaluated. All optimizations in this study were carried for dose of 6 Gy at dose optimization points. For both non-apex and apex models of vaginal cylinders, doses for apex point and three dome

An update on corrosion monitoring in cylinder storage yards

Energy Technology Data Exchange (ETDEWEB)

Henson, H.M.; Newman, V.S.; Frazier, J.L. [Oak Ridge K-25 Site, TN (United States)

1991-12-31

Depleted uranium, from US uranium isotope enrichment activities, is stored in the form of solid uranium hexafluoride (UF{sub 6}) in A285 and A516 steel cylinders designed and manufactured to ASME Boiler and Pressure Vessel Code criteria. In general, storage facilities are open areas adjacent to the enrichment plants where the cylinders are exposed to weather. This paper describes the Oak Ridge program to determine the general corrosion behavior of UF{sub 6} cylinders, to determine cylinder yard conditions which are likely to affect long term storage of this material, and to assess cylinder storage yards against these criteria. This program is targeted at conditions specific to the Oak Ridge cylinder yards. Based on (a) determination of the current cylinder yard conditions, (b) determination of rusting behavior in regions of the cylinders showing accelerated attack, (c) monitoring of corrosion rates through periodic measurement of test coupons placed within the cylinder yards, and (d) establishment of a computer base to incorporate and retain these data, the technical division is working with the enrichment sites to implement an upgraded system for storage of this material until such time as it is used or converted.

[Functional aspects of pelvic floor surgery].

Science.gov (United States)

Wagenlehner, F M E; Gunnemann, A; Liedl, B; Weidner, W

2009-11-01

Pelvic floor dysfunctions are frequently seen in females. The human pelvic floor is a complex structure and heavily stressed throughout female life. Recent findings in the functional anatomy of the pelvic floor have led to a much better understand-ing, on the basis of which enormous improvements in the therapeutic options have arisen. The pelvic floor activity is regulated by three main muscular forces that are responsible for vaginal tension and suspension of the pelvic floor -organs, bladder and rectum. For different reasons laxity in the vagina or its supporting ligaments as a result of altered connective tissue can distort this functional anatomy. A variety of symptoms can derive from these pelvic floor dysfunctions, such as urinary urge and stress incontinence, abnormal bladder emptying, faecal incontinence, obstructive bowel disease syndrome and pelvic pain. Pelvic floor reconstruction is nowadays driven by the concept that in the case of pelvic floor symptoms restoration of the anatomy will translate into restoration of the physiology and ultimately improve the patients' symptoms. The exact surgical reconstruction of the anatomy is there-fore almost exclusively focused on the restoration of the lax pelvic floor ligaments. An exact identification of the anatomic lesions preoperatively is eminently necessary, to allow for an exact anatomic reconstruction with respect to the muscular forces of the pelvic floor. Georg Thieme Verlag Stuttgart * New York.

Pelvic floor physical therapy in urogynecologic disorders.

Science.gov (United States)

Kotarinos, Rhonda K

2003-08-01

Physical therapists are uniquely qualified to treat pelvic floor dysfunction with conservative management techniques. Techniques associated with incontinence and support functions of the pelvic floor include bladder training and pelvic floor rehabilitation: pelvic floor exercises, biofeedback therapy, and pelvic floor electrical stimulation. Pain associated with mechanical pelvic floor dysfunction can be treated by physical therapists utilizing various manual techniques and modalities. Research documents that conservative management is effective in treating many conditions associated with pelvic floor dysfunction. Research should be conducted to determine if addressing diastasis recti and contracture of the pelvic floor musculature should be a component of the standard physical therapy protocol.

NGSI: Function Requirements for a Cylinder Tracking System

International Nuclear Information System (INIS)

Branney, S.

2012-01-01

While nuclear suppliers currently track uranium hexafluoride (UF 6 ) cylinders in various ways, for their own purposes, industry practices vary significantly. The NNSA Office of Nonproliferation and International Security's Next Generation Safeguards Initiative (NGSI) has begun a 5-year program to investigate the concept of a global monitoring scheme that uniquely identifies and tracks UF 6 cylinders. As part of this effort, NGSI's multi-laboratory team has documented the 'life of a UF 6 cylinder' and reviewed IAEA practices related to UF 6 cylinders. Based on this foundation, this paper examines the functional requirements of a system that would uniquely identify and track UF 6 cylinders. There are many considerations for establishing a potential tracking system. Some of these factors include the environmental conditions a cylinder may be expected to be exposed to, where cylinders may be particularly vulnerable to diversion, how such a system may be integrated into the existing flow of commerce, how proprietary data generated in the process may be protected, what a system may require in terms of the existing standard for UF 6 cylinder manufacture or modifications to it and what the limiting technology factors may be. It is desirable that a tracking system should provide benefit to industry while imposing as few additional constraints as possible and still meeting IAEA safeguards objectives. This paper includes recommendations for this system and the analysis that generated them.

Method to generate generic floor response spectra for operating nuclear power plant

International Nuclear Information System (INIS)

Curreri, J.; Costantino, C.; Subudhi, M.; Reich, M.

1985-01-01

The general approach in the development of the response spectra was to study the effects on the dynamic characteristics of each of the elements in the chain of events that goes between the loads and the responses. This includes the loads, the soils and the structures. A free-field earthquake response spectra was used to generate horizontal earthquake time histories. The excitation was applied through the soil and into the various structures to produce responses in equipment. An entire range of soil conditions was used with each structure, from soft soil to solid rock. Actual PWR and BWR - Mark I structural models were used as representative of a class of structures. For each model, the stiffness properties were varied, with the same mass, so as to extend the fundamental base structure natural frequency from 2 cps to 36 cps. This resulted in fundamental mode coupled natural frequencies as low as 0.86 cps and as high as 30 cps. From all of these models of soils and structures, floor response spectra were generated at each floor level. The natural frequencies of the structures were varied to obtain maximum response conditions. The actual properties were first used to locate the natural frequencies. The stiffness properties were then varied, with the same mass, to extend the range of the fundamental base structure natural frequency. The intention was to have the coupled structural material frequencies in the vicinity of the peak amplitude frequency content of the excitation spectrum. Particular attention was therefore given to the frequency band between 2 Hz and 4 Hz. A horizontal generic floor response spectra is proposed for the top level of a generic structure. Reduction factors are applied to the peak acceleration for equipment at lower levels

School Flooring Factors

Science.gov (United States)

McGrath, John

2012-01-01

With all of the hype that green building is receiving throughout the school facility-management industry, it's easy to overlook some elements that may not be right in front of a building manager's nose. It is helpful to examine the role floor covering plays in a green building project. Flooring is one of the most significant and important systems…

Theory of interacting dislocations on cylinders.

Science.gov (United States)

Amir, Ariel; Paulose, Jayson; Nelson, David R

2013-04-01

We study the mechanics and statistical physics of dislocations interacting on cylinders, motivated by the elongation of rod-shaped bacterial cell walls and cylindrical assemblies of colloidal particles subject to external stresses. The interaction energy and forces between dislocations are solved analytically, and analyzed asymptotically. The results of continuum elastic theory agree well with numerical simulations on finite lattices even for relatively small systems. Isolated dislocations on a cylinder act like grain boundaries. With colloidal crystals in mind, we show that saddle points are created by a Peach-Koehler force on the dislocations in the circumferential direction, causing dislocation pairs to unbind. The thermal nucleation rate of dislocation unbinding is calculated, for an arbitrary mobility tensor and external stress, including the case of a twist-induced Peach-Koehler force along the cylinder axis. Surprisingly rich phenomena arise for dislocations on cylinders, despite their vanishing Gaussian curvature.

Low-Re flow past an isolated cylinder with rounded corners

KAUST Repository

Zhang, Wei

2016-06-29

Direct numerical simulation is performed for flow past an isolated cylinder at Re=1,000. The corners of the cylinder are rounded at different radii, with the non-dimensional radius of curvature varying from R+=R/D=0.000 (square cylinder with sharp corners) to 0.500 (circular cylinder), in which R is the corner radius and D is the cylinder diameter. Our objective is to investigate the effect of the rounded corners on the development of the separated and transitional flow past the cylinder in terms of time-averaged statistics, time-dependent behavior, turbulent statistics and three-dimensional flow patterns. Numerical results reveal that the rounding of the corners significantly reduces the time-averaged drag and the force fluctuations. The wake flow downstream of the square cylinder recovers the slowest and has the largest wake width. However, the statistical quantities do not monotonically vary with the corner radius, but exhibit drastic variations between the cases of square cylinder and partially rounded cylinders, and between the latter and the circular cylinder. The free shear layer separated from the R+=0.125 cylinder is the most stable in which the first roll up of the wake vortex occurs furthest from the cylinder and results in the largest recirculation bubble, whose size reduces as R+ further increases. The coherent and incoherent Reynolds stresses are most pronounced in the near-wake close to the reattachment point, while also being noticeable in the shear layer for the square and R+=0.125 cylinders. The wake vortices translate in the streamwise direction with a convection velocity that is almost constant at approximately 80% of the incoming flow velocity. These vortices exhibit nearly the same trajectory for the rounded cylinders and are furthest away from the wake centerline for the square one. The flow past the square cylinder is strongly three-dimensional as indicated by the significant primary and secondary enstrophy, while it is dominated by the

Generation of floor response spectra for a model structure of nuclear power plant

International Nuclear Information System (INIS)

Vaidyanathan, C.V.; Kamatchi, P.; Ravichandran, R.; Lakshmanan, N.

2003-01-01

The importance of Nuclear power plants and the consequences of a nuclear accident require that the nuclear structures be designed for the most severe environmental conditions. Earthquakes constitutes major design consideration for the system, structures and equipment of a nuclear power plant. The design of structures on ground is based on the ground response spectra. Many important parts of a nuclear power plant facility are attached to the principal parts of the structure and respond in a manner determined by the structural response rather than by the general ground motion to which the structure is supported. Hence the seismic response of equipment is generally based on the response spectrum of the floor on which it is mounted. In this paper such floor response spectra have been generated at different nodes of a chosen model structure of a nuclear power plant. In the present study a detailed nonlinear time history analysis has been carried out on the mathematical model of the chosen Nuclear Power Plant model structure with the spectrum compatible time history. The acceleration response results of the time history analysis has been used in the spectral analysis and the response spectra are generated. Further peak broadening has been done to account for uncertainties in the material properties and soil characteristics. (author)

Self-accelerating parabolic cylinder waves in 1-D

Energy Technology Data Exchange (ETDEWEB)

Yuce, C., E-mail: cyuce@anadolu.edu.tr

2016-11-25

Highlights: • We find a new class of self-accelerating waves. • We show that parabolic cylinder waves self-accelerates in a parabolic potential. • We discuss that truncated parabolic cylinder waves propagates large distance without almost being non-diffracted in free space. - Abstract: We introduce a new self-accelerating wave packet solution of the Schrodinger equation in one dimension. We obtain an exact analytical parabolic cylinder wave for the inverted harmonic potential. We show that truncated parabolic cylinder waves exhibits their accelerating feature.

Price floors for emissions trading

International Nuclear Information System (INIS)

Wood, Peter John; Jotzo, Frank

2011-01-01

Price floors in greenhouse gas emissions trading schemes can guarantee minimum abatement efforts if prices are lower than expected, and they can help manage cost uncertainty, possibly as complements to price ceilings. Provisions for price floors are found in several recent legislative proposals for emissions trading. Implementation however has potential pitfalls. Possible mechanisms are government commitments to buy back permits, a reserve price at auction, or an extra fee or tax on acquittal of emissions permits. Our analysis of these alternatives shows that the fee approach has budgetary advantages and is more compatible with international permit trading than the alternatives. It can also be used to implement more general hybrid approaches to emissions pricing. - Research highlights: → Price floors for emissions trading schemes guarantee a minimum carbon price. → Price floors mean that emissions can be less than specified by the ETS cap. → We examine how price floors can relate to different policy objectives. → We compare different mechanisms for implementing a price floor. → We find that a mechanism where there is an extra tax or fee has advantages.

Floor heating systems

Energy Technology Data Exchange (ETDEWEB)

Radtke, U

1984-02-01

The question of whether PPC- and VPE-floor heating pipes can endure damage when incompletely imbedded in the floor finish is investigated in an experimental setup. An expansion of the pipe, caused by a temperature increase from 20/sup 0/C to 50/sup 0/C was measured and considered too small to deduce the degree of danger from the damage.

Macro-Encapsulated PCM Cylinder Module Based on Paraffin and Float Stones

Directory of Open Access Journals (Sweden)

Kailiang Huang

2016-05-01

Full Text Available Organic phase change material (PCM with macro-encapsulation is attractive in energy storage applications as it has relatively low cost. This study focuses on using PET plastic pipes to encapsulate paraffin and using low-cost float stones to increase the thermal conductivity of PCM modules as they have a special structure of high porosity. Float stones were immersed in the liquid PCM and an ultrasonic welding method used to prevent leakage of the PET plastic pipes. Scanning electron microscopy (SEM was used to discover the appearance of the composite PCM. The thermal performance of the PCM cylinder module was analyzed through experimental tests of a constant-temperature water bath and numerical simulations. The result indicates that this PCM Ccylinder module is superior in thermal energy storage compared with the reference module even though fewer PCM was contained and the latent heat loss is considerable. The pipe diameter is an important parameter when using this kind of PCM cylinder module in water tanks.

Application of the exact solution for scattering by an infinite cylinder to the estimation of scattering by a finite cylinder.

Science.gov (United States)

Wang, R T; van de Hulst, H C

1995-05-20

A new algorithm for cylindrical Bessel functions that is similar to the one for spherical Bessel functions allows us to compute scattering functions for infinitely long cylinders covering sizes ka = 2πa/λ up to 8000 through the use of only an eight-digit single-precision machine computation. The scattering function and complex extinction coefficient of a finite cylinder that is seen near perpendicular incidence are derived from those of an infinitely long cylinder by the use of Huygens's principle. The result, which contains no arbitrary normalization factor, agrees quite well with analog microwave measurements of both extinction and scattering for such cylinders, even for an aspect ratio p = l/(2a) as low as 2. Rainbows produced by cylinders are similar to those for spherical drops but are brighter and have a lower contrast.

Thermoelastic analysis of non-uniform pressurized functionally graded cylinder with variable thickness using first order shear deformation theory(FSDT) and perturbation method

Science.gov (United States)

Khoshgoftar, M. J.; Mirzaali, M. J.; Rahimi, G. H.

2015-11-01

Recently application of functionally graded materials(FGMs) have attracted a great deal of interest. These materials are composed of various materials with different micro-structures which can vary spatially in FGMs. Such composites with varying thickness and non-uniform pressure can be used in the aerospace engineering. Therefore, analysis of such composite is of high importance in engineering problems. Thermoelastic analysis of functionally graded cylinder with variable thickness under non-uniform pressure is considered. First order shear deformation theory and total potential energy approach is applied to obtain the governing equations of non-homogeneous cylinder. Considering the inner and outer solutions, perturbation series are applied to solve the governing equations. Outer solution for out of boundaries and more sensitive variable in inner solution at the boundaries are considered. Combining of inner and outer solution for near and far points from boundaries leads to high accurate displacement field distribution. The main aim of this paper is to show the capability of matched asymptotic solution for different non-homogeneous cylinders with different shapes and different non-uniform pressures. The results can be used to design the optimum thickness of the cylinder and also some properties such as high temperature residence by applying non-homogeneous material.

Pelvic floor and sexual male dysfunction

Directory of Open Access Journals (Sweden)

Antonella Pischedda

2013-04-01

Full Text Available The pelvic floor is a complex multifunctional structure that corresponds to the genito- urinary-anal area and consists of muscle and connective tissue. It supports the urinary, fecal, sexual and reproductive functions and pelvic statics. The symptoms caused by pelvic floor dysfunction often affect the quality of life of those who are afflicted, worsening significantly more aspects of daily life. In fact, in addition to providing support to the pelvic organs, the deep floor muscles support urinary continence and intestinal emptying whereas the superficial floor muscles are involved in the mechanism of erection and ejaculation. So, conditions of muscle hypotonia or hypertonicity may affect the efficiency of the pelvic floor, altering both the functionality of the deep and superficial floor muscles. In this evolution of knowledge it is possible imagine how the rehabilitation techniques of pelvic floor muscles, if altered and able to support a voiding or evacuative or sexual dysfunction, may have a role in improving the health and the quality of life.

46 CFR 58.30-30 - Fluid power cylinders.

Science.gov (United States)

2010-10-01

... all pneumatic power transmission systems. (b) Fluid power cylinders consisting of a container and a... 46 Shipping 2 2010-10-01 2010-10-01 false Fluid power cylinders. 58.30-30 Section 58.30-30... MACHINERY AND RELATED SYSTEMS Fluid Power and Control Systems § 58.30-30 Fluid power cylinders. (a) The...

Large Eddy simulation of turbulent flow past a circular cylinder in the subcritical and critical regimes

Energy Technology Data Exchange (ETDEWEB)

Lee, Kyongjun; Yang, Kyung-Soo [Inha University, Incheon (Korea, Republic of)

2017-04-15

Large Eddy simulation (LES) results of turbulent flow past a circular cylinder for the specified Reynolds numbers (Re = 63100, 126000, 252000) are presented. An immersed boundary method was employed to facilitate implementation of a circular cylinder in a Cartesian grid system. A dynamic subgrid-scale model, in which the model coefficient is dynamically determined by the current resolved flow field rather than assigned a prefixed constant, was implemented for accurate turbulence modeling. For better resolution near the cylinder surface and in the separated free-shear layers, a composite grid was used. Flow statistics including mean and rms values of force coefficients and Strouhal number of vortex shedding, are presented. Flow visualization using vorticity or Q contours are also shown. Our results are in better agreement with the MARIN measurements compared with RANS calculations reported in the previous ITTC workshop, confirming that LES is a more appropriate simulation methodology than a RANS approach to predict VIV for marine structures.

Mixture distribution in a multi-valve twin-spark ignition engine equipped with high-pressure multi-hole injectors

International Nuclear Information System (INIS)

Mitroglou, N; Arcoumanis, C; Mori, K; Motoyama, Y

2006-01-01

Laser-induced fluorescence has been mainly used to characterise the two-dimensional fuel vapour concentration inside the cylinder of a multi-valve twin-spark ignition engine equipped with high-pressure multi-hole injectors. The effects of injection timing, in-cylinder charge motion and injector tip layout have been quantified. The flexibility in nozzle design of the multi-hole injectors has proven to be a powerful tool in terms of matching overall spray cone angle and number of holes to specific engine configurations. Injection timing was found to control spray impingement on the piston and cylinder wall, thus contributing to quick and efficient fuel evaporation. It was confirmed that in-cylinder charge motion plays a major role in engine's stable operation by assisting in the transportation of the air-fuel mixture towards the ignition locations (i.e. spark-plugs) in the way of a uniformly distributed charge or by preserving stratification of the charge depending on operating mode of the engine

Nonlinear bending and collapse analysis of a poked cylinder and other point-loaded cylinders

International Nuclear Information System (INIS)

Sobel, L.H.

1983-06-01

This paper analyzes the geometrically nonlinear bending and collapse behavior of an elastic, simply supported cylindrical shell subjected to an inward-directed point load applied at midlength. The large displacement analysis results for this thin (R/t = 638) poked cylinder were obtained from the STAGSC-1 finite element computer program. STAGSC-1 results are also presented for two other point-loaded shell problems: a pinched cylinder (R/t = 100), and a venetian blind (R/t = 250)

Maxillary Sinus Floor Augmentation

DEFF Research Database (Denmark)

Starch-Jensen, Thomas; Jensen, Janek Dalsgaard

2017-01-01

, radiological and histomorphometric outcome as well as complications are presented after maxillary sinus floor augmentation applying the lateral window technique with a graft material, maxillary sinus membrane elevation without a graft material and osteotome-mediated sinus floor elevation with or without...

The effect of sub-floor heating on house-dust-mite populations on floors and in furniture.

Science.gov (United States)

de Boer, Rob

2003-01-01

It is well known that dehydrating conditions for house dust mites can be created by simply raising the temperature, causing loss of body water and eventually death. Thus, it can be expected that conditions for dust mites are less favourable on floors supplied with sub-floor heating. This was examined in a study of 16 houses with sub-floor heating and 21 without. The pattern of changes in air humidity and temperature on the floors was investigated and compared to known data of the tolerance of dust mites. Also the resident mite populations were compared. Floors with sub-floor heating had, on average, fewer mites, but the difference with unheated floors was small. It was remarkable that mite numbers were also lower in upholstered furniture. Another important observation was that some houses with sub-floor heating had high mite numbers, indicating that this type of heating is compatible with a thriving mite population. Temperature and humidity conditions of heated floors may allow mites not only to survive, but also to remain active in winter. A moderate increase in temperature, a moderate decrease in (absolute) air humidity, or a combination of both, will suffice to keep the humidity all winter below the Critical Equilibrium Humidity, the level of air humidity that is critical for mite growth and reproduction, hence for allergen production. However, it is argued that measures to suppress allergen production by house dust mites are likely to be far more effective if taken in summer rather than in winter.

Experimental seismic test of fluid coupled co-axial cylinders

International Nuclear Information System (INIS)

Chu, M.L.; Brown, S.J.; Lestingi, J.F.

1979-01-01

The dynamic response of fluid coupled coaxial cylindrical shells is of interest to the nuclear industry with respect to the seismic design of the reactor vessel and thermal liner. The experiments described present a series of tests which investigate the effect of the annular clearance between the cylinders (gap) on natural frequency, damping, and seismic response of both the inner and outer cylinders. The seismic input is a time history base load to the flexible fluid filled coaxial cylinders. The outer cylinder is elastically supported at both ends while the inner cylinder is supported only at the base (lower) end

Development of floor smear sampler (floor radioactive contamination measuring instrument) for nuclear facilities

International Nuclear Information System (INIS)

Miyagawa, Minoru; Ito, Haruo; Nozawa, Katsuro; Shinohara, Yotaro; Hashimoto, Hiroshi.

1980-01-01

The control of the floor contamination with radioactive substances in nuclear facilities is strictly carried out by smear method, in which the contaminants on floor surfaces are wiped off with filter papers or cloths, and the contamination density on the floor surfaces is measured through their intensity of radioactivity. This wiping work is laborious since it is carried out in leaning-over posture when many samples must be taken in wide floor area. Therefore, to achieve labor saving in this work, an automatic sampler was developed. In the floor smear sampler developed, samples are taken on long band type wiping cloths only by handle operation, and the sample numbers are printed. When many samples are taken in wide floor area, this is especially effective, and the labor saving by 1/3 to 1/2 can be achieved. At present, this sampler is put in practical use in Hamaoka Nuclear Power Station. At the time of trial manufacture, the method of wiping, the mechanisms of wiping, cloth feeding and running, the contact pressure and the number of times of wiping affecting wiping efficiency and the required torque of a motor were examined. The developed sampler is that of constant contact pressure, vibration wiping type, and the rate of sampling is 10 sec per one sample. 100 samples can be taken on one roll of wiping cloth. The results of performance test are reported. (Kako, I.)

On fundamental concept of anti-earthquake design of equipment and pipings

International Nuclear Information System (INIS)

Shibata, H.; Kato, M.

1979-01-01

This paper deals with a new concept of anti-earthquake design of equipment and pipings in nuclear power plants. Usual anti-earthquake design of such items starts from the design basis ground motions, via floor responses and ends at the stress analysis of each structural element. However, the same type of equipment are used for plants under various site conditions. The ordinarily used method obliges the repetition of such design procedure on each plant. This new design method has been developed to avoid such time-consuming repetitions. (orig.)

Results of ultrasonic testing evaluations on UF6 storage cylinders

International Nuclear Information System (INIS)

Lykins, M.L.

1997-02-01

The three site cylinder management program is responsible for the safe storage of the DOE owned UF 6 storage cylinders at PORTS, PGDP and at the K-25 site. To ensure the safe storage of the UF 6 in the cylinders, the structural integrity of the cylinders must be evaluated. This report represents the latest cylinder integrity investigation that utilized wall thickness evaluations to identify thinning due to atmospheric exposure

Low-Re flow past an isolated cylinder with rounded corners

KAUST Repository

Zhang, Wei; Samtaney, Ravi

2016-01-01

rounded cylinders, and between the latter and the circular cylinder. The free shear layer separated from the R+=0.125 cylinder is the most stable in which the first roll up of the wake vortex occurs furthest from the cylinder and results in the largest

Low-energy house in Sisimiut - Measurement equipment

Energy Technology Data Exchange (ETDEWEB)

Hvidthoeft Delff Andersen, P.; Rode, C.; Madsen, Henrik

2013-08-15

This paper documents the measurement equipment in a low-energy house in Sisimiut, Greenland. Detailed measurements are being taken on energy consumption, indoor temperatures, floor heating, ventilation, open/closed state of doors and windows, and indoors climate. Equipped with a central control unit, experiments can be designed in order to study heat dynamics of the building. It is described how to plan and execute such experiments in one apartment in the building. The building also features both a solar thermal system and extra buffer tank facilitating testing of storage strategies on the power generated by the solar thermal system. A weather station equipped with thermometer, pyranometer and anemometer is installed on the building as well. Finally, it is described how to retrieve data from an SQL server which is configured to take monthly backups. R functions have been implemented to fetch and prepare the data for time series analysis. Examples are given on the use of these. (Author)

Label inspection of approximate cylinder based on adverse cylinder panorama

Science.gov (United States)

Lin, Jianping; Liao, Qingmin; He, Bei; Shi, Chenbo

2013-12-01

This paper presents a machine vision system for automated label inspection, with the goal to reduce labor cost and ensure consistent product quality. Firstly, the images captured from each single-camera are distorted, since the inspection object is approximate cylindrical. Therefore, this paper proposes an algorithm based on adverse cylinder projection, where label images are rectified by distortion compensation. Secondly, to overcome the limited field of viewing for each single-camera, our method novelly combines images of all single-cameras and build a panorama for label inspection. Thirdly, considering the shake of production lines and error of electronic signal, we design the real-time image registration to calculate offsets between the template and inspected images. Experimental results demonstrate that our system is accurate, real-time and can be applied for numerous real- time inspections of approximate cylinders.

Linear Alkylbenzenesulfonates in indoor Floor Dust

DEFF Research Database (Denmark)

Madsen, Jørgen Øgaard; Wolkoff, Peder; Madsen, Jørgen Øgaard

1999-01-01

The amount of Linear Alkylbenzenesulfonates (LAS) in the particle fraction of floor dust sampled from 7 selected public buildings varied between 34 and 1500 microgram per gram dust, while the contents of the fibre fractions generally were higher with up to 3500 microgram LAS/g dust. The use...... of a cleaning agent with LAS resulted in an increase of the amount of LAS in the floor dust after floor wash relative to just before floor wash. However, the most important source of LAS in the indoor floor dust appears to be residues of detergent in clothing. Thus, a newly washed shirt contained 2960 microgram...

Effects of Floor Covering Resistance of a Radiant Floor on System Energy and Exergy Performances

DEFF Research Database (Denmark)

Kazanci, Ongun Berk; Shukuya, Masanori; Olesen, Bjarne W.

2016-01-01

Floor covering resistance (material and thickness) can be influenced by subjective choices (architectural design, interior design, texture, etc.) with significant effects on the performance of a radiant heating and cooling system. To study the effects of floor covering resistance on system...... performance, a water-based radiant floor heating and cooling system (dry, wooden construction) was considered to be coupled to an air-to-water heat pump, and the effects of varying floor covering resistances (0.05 m2K/W, 0.09 m2K/W and 0.15 m2K/W) on system performance were analyzed in terms of energy...... and exergy. In order to achieve the same heating and cooling outputs, higher average water temperatures are required in the heating mode (and lower temperatures in the cooling mode) with increasing floor covering resistance. These temperature requirements decrease the heat pump’s performance (lower...

Enrichment Assay Methods Development for the Integrated Cylinder Verification System

Energy Technology Data Exchange (ETDEWEB)

Smith, Leon E.; Misner, Alex C.; Hatchell, Brian K.; Curtis, Michael M.

2009-10-22

International Atomic Energy Agency (IAEA) inspectors currently perform periodic inspections at uranium enrichment plants to verify UF6 cylinder enrichment declarations. Measurements are typically performed with handheld high-resolution sensors on a sampling of cylinders taken to be representative of the facility's entire product-cylinder inventory. Pacific Northwest National Laboratory (PNNL) is developing a concept to automate the verification of enrichment plant cylinders to enable 100 percent product-cylinder verification and potentially, mass-balance calculations on the facility as a whole (by also measuring feed and tails cylinders). The Integrated Cylinder Verification System (ICVS) could be located at key measurement points to positively identify each cylinder, measure its mass and enrichment, store the collected data in a secure database, and maintain continuity of knowledge on measured cylinders until IAEA inspector arrival. The three main objectives of this FY09 project are summarized here and described in more detail in the report: (1) Develop a preliminary design for a prototype NDA system, (2) Refine PNNL's MCNP models of the NDA system, and (3) Procure and test key pulse-processing components. Progress against these tasks to date, and next steps, are discussed.

Enrichment Assay Methods Development for the Integrated Cylinder Verification System

International Nuclear Information System (INIS)

Smith, Leon E.; Misner, Alex C.; Hatchell, Brian K.; Curtis, Michael M.

2009-01-01

International Atomic Energy Agency (IAEA) inspectors currently perform periodic inspections at uranium enrichment plants to verify UF6 cylinder enrichment declarations. Measurements are typically performed with handheld high-resolution sensors on a sampling of cylinders taken to be representative of the facility's entire product-cylinder inventory. Pacific Northwest National Laboratory (PNNL) is developing a concept to automate the verification of enrichment plant cylinders to enable 100 percent product-cylinder verification and potentially, mass-balance calculations on the facility as a whole (by also measuring feed and tails cylinders). The Integrated Cylinder Verification System (ICVS) could be located at key measurement points to positively identify each cylinder, measure its mass and enrichment, store the collected data in a secure database, and maintain continuity of knowledge on measured cylinders until IAEA inspector arrival. The three main objectives of this FY09 project are summarized here and described in more detail in the report: (1) Develop a preliminary design for a prototype NDA system, (2) Refine PNNL's MCNP models of the NDA system, and (3) Procure and test key pulse-processing components. Progress against these tasks to date, and next steps, are discussed.

Sub-wavelength metamaterial cylinders with multiple dipole resonances

DEFF Research Database (Denmark)

Arslanagic, Samel; Breinbjerg, Olav

2009-01-01

It has been shown that the sub-wavelength resonances of the individual MTM cylinders also occur for electrically small configurations combining 2 or 4 cylinders. For the 2-and 4-cylinder configurations the overall size is 1/20 and 1/12.5 of the smallest wavelength, respectively. These MTM...... configuration thus offer the possibility for multi-resonant electrically small configurations....

Energy Absorption of Monolithic and Fibre Reinforced Aluminium Cylinders

NARCIS (Netherlands)

De Kanter, J.L.C.G.

2006-01-01

Summary accompanying the thesis: Energy Absorption of Monolithic and Fibre Reinforced Aluminium Cylinders by Jens de Kanter This thesis presents the investigation of the crush behaviour of both monolithic aluminium cylinders and externally fibre reinforced aluminium cylinders. The research is based

Turbulence and heat transfer in condensate in drying cylinders at high g-forces. Phase 2; Turbulens och vaermeoeverfoering i kondensat i torkcylindrar vid hoega g-krafter. Fas 2

Energy Technology Data Exchange (ETDEWEB)

Stenstroem, Stig; Ingvarsson, David [Lund Inst. of Tech. (Sweden). Dept. of Chemical Engineering

2006-02-15

During paper drying a condensate layer is formed on the inside surface of the rotating cylinder which acts as resistance for heat transfer through the cylinder. The heat transfer resistance in the condensate layer is mainly dependant on the layer thickness and the turbulence in the layer. Consequently the resistance increases with higher cylinder speeds due to increased centrifugal forces and thus reduced turbulence in the layer. In order to minimize the influence of condensate on the heat transfer process the cylinder used in Phase 1 has been equipped with axial grooves. The aim of the project has been to study the water movement in the cylinder and to investigate how the drying capacity is influenced by condensate accumulating in the grooves rather than moving along the smooth surface of a paper dryer cylinder. This knowledge should be considered preferably before construction of cylinders for new machines. For existing machines with smooth cylinders the importance of axial vertical flanges for improved heat transfer has been investigated. In addition the capacity of stationary siphons has been evaluated. The results are of importance for the manufacturers of paper machines as well as the producing newsprint and printing paper companies. According to the results from the experiments the water flows mainly in the grooves, assuming that the number of grooves and that the dimensions of the grooves are adjusted to the water load. Then the surfaces between the grooves can be considered as completely dry unlike in a smooth cylinder where the surfaces more or less are covered with a thin layer of condensate. Furthermore the centrifugal force helps the water to flow down into the grooves. Consequently a high water flow will rely on a high cylinder speed in order to keep the water flowing into the axial grooves. The computer simulations show that the drying capacity increases with up to 46 % in dryer cylinders provided with axial grooves compared to smooth cylinders

MONOMIALS AND BASIN CYLINDERS FOR NETWORK DYNAMICS.

Science.gov (United States)

Austin, Daniel; Dinwoodie, Ian H

We describe methods to identify cylinder sets inside a basin of attraction for Boolean dynamics of biological networks. Such sets are used for designing regulatory interventions that make the system evolve towards a chosen attractor, for example initiating apoptosis in a cancer cell. We describe two algebraic methods for identifying cylinders inside a basin of attraction, one based on the Groebner fan that finds monomials that define cylinders and the other on primary decomposition. Both methods are applied to current examples of gene networks.

The managerial issues related to transferring shop floor knowledge in manufacturing relocation

DEFF Research Database (Denmark)

Knudsen, Mette Præst; Madsen, Erik Skov

2014-01-01

Purpose – The purpose of this paper is to explore the specific practices of management in the dispatching unit and to identify mechanisms for supporting transfer of shop floor knowledge embedded in operating manufacturing equipment. Design/methodology/approach – The paper applies an inductive...... and a case study approach for exploring three empirical cases that represent different manufacturing facility relocation processes and differences in the applied managerial practices. Findings – The paper identifies two important gaps in international production literature when firms relocate equipment...... to other sites; a time gap (from dismantling to re-assembly of production facilities) and a space gap (from the current to the new site abroad). These gaps are important for understanding why relocation processes are difficult and what management can do to facilitate such processes. Practical implications...

Investigating the fall-injury reducing effect of impact absorbing flooring among female nursing home residents: initial results.

Science.gov (United States)

Gustavsson, Johanna; Bonander, Carl; Andersson, Ragnar; Nilson, Finn

2015-10-01

Fall-related injuries affect the lives of elderly to a substantial degree. This quasi-experimental study investigates the fall-injury reducing effect of impact absorbing flooring among female nursing home residents. The intervention site is a nursing home in Sweden where impact absorbing flooring was installed in parts of one of six wards (six out of 10 apartments (excluding bathrooms), the communal dining-room and parts of the corridor). The impact absorbing flooring is a 12 mm thick closed cell flexible polyurethane/polyurea composite tile (500×500 mm) with an exterior surface of polyurethane/polyurea. A generalised linear model (log-binomial) was used to calculate the RR of injury from falls on impact absorbing flooring compared to falls on regular flooring, adjusted for age, body mass index, visual and cognitive impairments. During the study period (1 October 2011 to 31 March 2014), 254 falls occurred on regular flooring and 77 falls on impact absorbing flooring. The injury/fall rate was 30.3% for falls on regular flooring and 16.9% for falls on impact absorbing flooring. Adjusted for covariates, the impact absorbing flooring significantly reduced the RR of injury in the event of a fall by 59% (RR 0.41 (95% Cl 0.20 to 0.80)). This is, to our knowledge, the first study evaluating the injury-reducing effect of impact absorbing flooring in a nursing home showing statistically significant effect. The results from this study are promising, indicating the considerable potential of impact absorbing flooring as a fall-related injury intervention among frail elderly. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Predicition of the first spinning cylinder test using continuum damage mechanics

International Nuclear Information System (INIS)

Lidbury, D.P.G.; Sherry, A.H.; Bilby, B.A.; Howard, I.C.; Li, Z.H.; Eripret, C.

1993-01-01

For many years large-scale experiments have been performed world-wide to validate aspects of fracture mechanics methodology. Special emphasis has been given to correlations between small- and large-scale specimen behaviour in quantifying the structural behaviour of pressure vessels, piping and closures. Within this context, the first three Spinning Cylinder Tests, performed by AEA Technology at its Risley Laboratory, addressed the phenomenon of stable crack growth by ductile tearing in contained yield and conditions simulating pressurized thermal shock loading in a PWR reactor pressure vessel. A notable feature of the test data was that the effective resistance to crack growth, as measured in terms of the J R-curve, was appreciably greater than that anticipated from small-scale testing, both at initiation and after small amounts (a few millimeters) of tearing. In the present paper, two independent finite element analyses of the First Spinning Cylinder Test (SC 1) are presented and compared. Both involved application of the Rousselier ductile damage theory in an attempt to better understand the transferability of test data from small specimens to structural validation tests. In each instance, the parameters associated with the theory's constitutive equation were calibrated in terms of data from notched-tensile and (or) fracture mechanics tests, metallographic observation and (or) chemical composition. The evolution of ductile damage local to the crack tip during SC 1 was thereby calculated and, together with a crack growth criterion based on the maximization of opening-mode stress, used as the basis for predicting cylinder R-Curves (angular velocity vs. Δa, J-integral vs. Δa). The results show the Rousselier model to be capable of correctly predicting the enhancement of tearing toughness of the cylinder relative to that of conventional test specimens, given an appropriate choice of finite element cell size in the region representing the crack tip

SU-F-18C-11: Diameter Dependency of the Radial Dose Distribution in a Long Polyethylene Cylinder

Energy Technology Data Exchange (ETDEWEB)

Bakalyar, D; McKenney, S [Henry Ford Health System, Detroit, MI (United States); Feng, W [New York Presbyterian Hospital, Tenafly, NJ (United States)

2014-06-15

Purpose: The radial dose distribution in the central plane of a long cylinder following a long CT scan depends upon the diameter and composition of the cylinder. An understanding of this behavior is required for determining the spatial average of the dose in the central plane. Polyethylene, the material for construction of the TG200/ICRU phantom (30 cm in diameter) was used for this study. Size effects are germane to the principles incorporated in size specific dose estimates (SSDE); thus diameter dependency was explored as well. Method: ssuming a uniform cylinder and cylindrically symmetric conditions of irradiation, the dose distribution can be described using a radial function. This function must be an even function of the radial distance due to the conditions of symmetry. Two effects are accounted for: The direct beam makes its weakest contribution at the center while the contribution due to scatter is strongest at the center and drops off abruptly at the outer radius. An analytic function incorporating these features was fit to Monte Carlo results determined for infinite polyethylene cylinders of various diameters. A further feature of this function is that it is integrable. Results: Symmetry and continuity dictate a local extremum at the center which is a minimum for the larger sizes. The competing effects described above can Resultin an absolute maximum occurring between the center and outer edge of the cylinders. For the smallest cylinders, the maximum dose may occur at the center. Conclusion: An integrable, analytic function can be used to characterize the radial dependency of dose for cylindrical CT phantoms of various sizes. One use for this is to help determine average dose distribution over the central cylinder plane when equilibrium dose has been reached.

Pyroclastic Deposits in the Floor-fractured Crater Alphonsus

Science.gov (United States)

Allen, Carlton C.; Donaldson-Hanna, Kerri L.; Pieters, Carle M.; Moriarty, Daniel P.; Greenhagen, Benjamin T.; Bennett, Kristen A.; Kramer, Georgiana Y.; Paige, David A.

2013-01-01

samples, but within the range of analyzed pyroclastic glasses. The NAC images of the pyroclastic vents highlight their bright wall materials. The M3 spectra of the southeastern vent indicate that this bright material is noritic, likely crater floor material exposed by explosive eruption. These observations address the hypothesis that Nubium lavas intruded the fracture network beneath Alphonsus, leading to localized vulcanian-style eruptions. This model implies that the eruption products should be dominated by crystalline basalt fragments similar in elemental composition and mineralogy to mare lavas. The bright noritic material exposed in the vent walls is consistent with explosive eruptions. The estimated FeO abundances for the pyroclastic deposits are too low to be consistent with FeO abundances measured in mare basalts, but are within the range of pyroclastic glass samples. The visible- to near-infrared (VIS-NIR) spectra of the pyroclastic deposits and Nubium soils are significantly different, suggesting that the pyroclastics are unrelated to the mare basalts. The pyroclastic spectra are consistent with Fe-bearing glass plus small amounts of noritic wall rock. Similar glassy materials dominate regional pyroclastic deposits, suggesting a deep source for the pyroclastics observed in Alphonsus.

Unresolved Safety Issue A-46 - seismic qualification of equipment in operating plants

International Nuclear Information System (INIS)

Anderson, N.

1985-01-01

Seismic Qualification of Equipment in Operating Plants was designated as an Unresolved Safety Issue (USI) in December, 1980. The USI A-46 program was developed in early 1981 to investigate the adequacy of mechanical and electrical equipment in operating plants to withstand a safe shutdown earthquake. The approach taken was to develop viable, cost effective alternatives to current seismic qualification licensing requirements which could be applied to operating nuclear power plants. The tasks investigated include: (1) identification of seismic sensitive systems and equipment; (2) assessment of adequacy of existing seismic qualification methods; (3) development and assessment of in-situ test procedures to assist in qualification of equipment; (4) seismic qualification of equipment using seismic experience data; and (5) development of methods to generate generic floor response spectra. Progress to date and plans for completion of resolution are reported

A comparative study on thermal efficiency between the present floor and a ceramic floor

Energy Technology Data Exchange (ETDEWEB)

Kim, Y.M.; Kim, K.S. [Korea Institute of Science and Technology, Seoul (Korea, Republic of); Choi, B.S. [Kyung Hee University, Yongin (Korea, Republic of); Ko, J.S.; Park, S.K. [Bomwoo and Co. LTD., Kwangju (Korea, Republic of)

1999-04-01

A ceramic floor with improved thermal conductivity and efficiency has been developed in this study. The new ceramic floor minimizes the shrinkage rate to below 0.07% and shows almost no cleavage. There is no need to repair the ceramic floor because its bottom surface is flat. It especially shows an excellent performance in the test of a compressive strength (300 kg/cm{sup 2} based on 28 days), a flexural strength (64 kg/cm{sup 2} based on 28 days), and a convenient pressing. It is lighter than the present floor and it is expected to be applicable for a self-leveling ceramic motar in the residences and apartments. It shows an excellent character in the thermal conductivity and other physical properties compare to the present cement mortar. 5 refs., 3 figs., 2 tabs.

Floors: Care and Maintenance.

Science.gov (United States)

Post Office Dept., Washington, DC.

Guidelines, methods and policies regarding the care and maintenance of post office building floors are overviewed in this handbook. Procedures outlined are concerned with maintaining a required level of appearance without wasting manpower. Flooring types and characteristics and the particular cleaning requirements of each type are given along with…

Imperfection effects on the buckling of hydrostatically loaded cylinders

DEFF Research Database (Denmark)

Pinna, Rodney; Madsen, Søren

2015-01-01

imperfection sensitivity. Work on cylinders with other loading conditions, such as hydrostatic loading, is more limited. Similarly, there is limited work on cylinders with boundary conditions other than simply-supported ends. This paper looks at the case of cylinders under hydrostatic load, which is often...

Dynamic Measurement of Extra Long Stroke Cylinder in the Pneumatic System

International Nuclear Information System (INIS)

Chang Ho; Lan Chouwei; Chen, L-C

2006-01-01

This paper sets up the measure and control system of the dynamic characteristics of the extra long stroke cylinder. In the different types of the control conditions (e.g. different control law, operating pressure and direct control valves), using the measure and control system to measure the relation between the pressure and the velocity of the motion of the long stroke cylinder and to observe the stick slip phenomenon of the motion of the long stroke cylinder. In the innovate measurement system, two pressure sensors are set on the long stroke cylinder to measure the difference of the pressure between the inlet and the exhaust of the long stroke cylinder. In additions, a draw line encoder is set on the system to measure the position and the velocity of the motion of the long stroke cylinder. The measuring data of the measure system is transferred to the computer via A/D interface card and counter card, and Home-made program of Haptic Interface Device is used to control the system, saving the data of the motion of the long stroke cylinder. The system uses different types of direction control valve to control the motion of the long stroke cylinder and compares the difference of the motion of the long stroke cylinder. The results show that the motion of the cylinder that pauses in the middle of the cylinder stroke and causes the stick slip phenomenon is more violent than the stick slip phenomenon in other position. When the length of the pause time reaches the some range, the acceleration of the motion of the cylinder will be rised substantially. This paper not only focuses on the testing method of the dynamic characteristics of the motion of the long stroke cylinder, but also includes the analysis of the dynamic characteristics of the motion of the long stroke cylinder. It provides the data of the dynamic characteristics of the motion of the long stroke cylinder to improve and design the pneumatic system of the long stroke cylinder

Inner and outer cylinders of the CMS vacuum tank.

CERN Multimedia

Patrice Loïez

2002-01-01

The vacuum tank of the CMS magnet system consists of inner and outer stainless-steel cylinders and houses the superconducting coil. The inner cylinder contains all the barrel sub-detectors, which it supports via a system of horizontal rails. The cylinder is pictured here in the vertical position on a yellow platform mounted on the ferris-wheel support structure. This will allow it to be pivoted and inserted into the already installed outer cylinder, through which this photo was taken.

Flow past two tandem square cylinders vibrating transversely in phase

International Nuclear Information System (INIS)

Mithun, M G; Tiwari, Shaligram

2014-01-01

Numerical investigations have been carried out to study the wake characteristics of flow past two tandem square cylinders vibrating in phase. Both the cylinders vibrate in a transverse direction, i.e., perpendicular to the incoming flow with the same frequency and amplitude. The frequency of vibration of the cylinders and the inter-cylinder spacing are varied for fixed values of the Reynolds number (Re = 100) and the amplitude ratio (A/D = 0.4). The synchronous or lock-in regime for the oscillatory wake of the vibrating cylinders has been identified by varying the frequency of the vibration from f e  = 0.4 f 0 to 1.6 f 0 (f 0 being the frequency of vortex shedding behind a stationary square cylinder). The characteristics of lift and drag and the mechanism of vortex shedding are studied by varying the excitation frequency within the lock-in range for each value of inter-cylinder spacing. The complex interaction of flow between the cylinders gives rise to a variety of characteristically different shedding patterns in their wake. For values of inter-cylinder spacing equal to 2D and 3D, periodic, as well as quasi-periodic, lock-in behaviors are observed in the synchronous range. (paper)

76 FR 38697 - High Pressure Steel Cylinders From China

Science.gov (United States)

2011-07-01

... imports from China of high pressure steel cylinders, provided for in subheading 7311.00.00 of the... threatened with material injury by reason of LTFV and subsidized imports of high pressure steel cylinders... contained in USITC Publication 4241 (July 2011), entitled High Pressure Steel Cylinders from China...

Experiments of flow-induced in-line oscillation of a circular cylinder in a water tunnel. 2. Influence of the aspect ratio of a cantilevered circular cylinder

International Nuclear Information System (INIS)

Nakamura, Akira; Okajima, Atsushi; Kosugi, Takashi

2001-01-01

The flow-induced in-line oscillation of a cantilevered circular cylinder was experimentally studied through free-oscillation tests in a water tunnel. The response displacement amplitude at a circular cylinder tip was measured at reduced velocity from 1.0 to 4.0. A cantilevered cylinder was supported by a plate spring mounted on the water tunnel wall. The cylinder aspect ratio was varied from 5 to 21 to investigate the effect of aspect ratio on the response displacement. It is found that cylinders with aspect ratios of 5 and 10 have one excitation region, while cylinders with aspect ratios of 14 and 21 have two excitation regions. The aspect ratio, therefore, affects the amplitude of the excitation regions. The influence of end-effect was also investigated using cylinders with an end plate attached to the free end. Since the cylinders with an end plate show two excitation regions, even at an aspect ratio of 5, the flow around the free end of a cantilevered cylinder causes the end-effect. The mechanism of vibration was investigated using a cylinder with a splitter plate in wake to prevent alternate vortices. The amplitude is greater than those of a normal cylinder without a splitter plate, especially at V r =2.3 to 3.0, where a cylinder with an end plate shows the second excitation region. In order words, the alternate vortices suppress the amplitude in this range. The maximum amplitude of each excitation region decreases in proportion to C n and the amplitude of the first excitation is more sensitive to C n . (author)

Modeling flow for modified concentric cylinder rheometer geometry

Science.gov (United States)

Ekeruche, Karen; Connelly, Kelly; Kavehpour, H. Pirouz

2016-11-01

Rheology experiments on biological fluids can be difficult when samples are limited in volume, sensitive to degradation, and delicate to extract from tissues. A probe-like geometry has been developed to perform shear creep experiments on biological fluids and to use the creep response to characterize fluid material properties. This probe geometry is a modified concentric cylinder setup, where the gap is large and we assume the inner cylinder rotates in an infinite fluid. To validate this assumption we perform shear creep tests with the designed probe on Newtonian and non-Newtonian fluids and vary the outer cylinder container diameter. We have also created a numerical model based on the probe geometry setup to compare with experimental results at different outer cylinder diameters. A creep test is modeled by applying rotation to the inner cylinder and solving for the deformation of the fluid throughout the gap. Steady state viscosity values are calculated from creep compliance curves and compared between experimental and numerical results.

Professional issues in the use of diagnostic ultrasound biofeedback in physiotherapy of the female pelvic floor

International Nuclear Information System (INIS)

McKiernan, Sharmaine; Chiarelli, Pauline; Warren-Forward, Helen

2013-01-01

The usage of diagnostic ultrasound equipment has expanded into physiotherapy. The aim of this paper is to deliver to both the ultrasound and physiotherapy professions an understanding of the use of diagnostic ultrasound for biofeedback in physiotherapy of the female pelvic floor and the issues related to competent and safe practice, including accessing suitable training. This has been evaluated using a qualitative research paradigm with data gathered via focus groups of Australian physiotherapists. The target group were pelvic floor physiotherapists as this is one of the main uses of diagnostic ultrasound within physiotherapy and the main area physiotherapists would like to be trained in. Two focus groups were run with a total of sixteen physiotherapists. Focus group participants reported their training in diagnostic ultrasound to be largely self directed. They also reported they were learning on their patients. Despite very limited training, participants demonstrated some familiarity with images and equipment settings. Participants felt the modality had a role within physiotherapy as an adjunct to their current practices. The main need raised by participants during the focus groups was related to patient expectations and the fact that the physiotherapist may miss evidence of pathology

Natural convection heat transfer on two horizontal cylinders in liquid sodium

Energy Technology Data Exchange (ETDEWEB)

Hata, K.; Shiotsu, M.; Takeuchi, Y. [Institute of Atomic Energy, Kyoto Univ. (Japan)] [and others

1995-09-01

Natural convection heat transfer on two horizontal 7.6 mm diameter test cylinders assembled with the ratio of the distance between each cylinder axis to the cylinder diameter, S/D, of 2 in liquid sodium was studied experimentally and theoretically. The heat transfer coefficients on the cylinder surface due to the same heat inputs ranging from 1.0 X 10{sup 7} to 1.0 x 10{sup 9} W/m{sup 3} were obtained experimentally for various setting angeles, {gamma}, between vertical direction and the plane including both of these cylinder axis over the range of zero to 90{degrees}. Theoretical equations for laminar natural convection heat transfer from the two horizontal cylinders were numerically solved for the same conditions as the experimental ones considering the temperature dependence of thermophysical properties concerned. The average Nusselt numbers, Nu, values on the Nu versus modified Rayleigh number, R{sub f}, graph. The experimental values of Nu for the upper cylinder are about 20% lower than those for the lower cylinder at {gamma} = 0{degrees} for the range of R{sub f} tested here. The value of Nu for the upper cylinder becomes higher and approaches that for the lower cylinder with the increase in {gamma} over range of 0 to 90{degrees}. The values of Nu for the lower cylinder at each {gamma} are almost in agreement with those for a single cylinder. The theoretical values of Nu on two cylinders except those for R{sub f}<4 at {gamma} = 0{degrees} are in agreement with the experimental data at each {gamma} with the deviations less than 15%. Correlations for Nu on the upper and lower cylinders were obtained as functions of S/D and {gamma} based n the theoretical solutions for the S/D ranged over 1.5 to 4.0.

Building with electromagnetic shield structure for individual floors

International Nuclear Information System (INIS)

Takahashi, T.; Nakamura, M.; Yabana, Y.; Ishikawa, T.; Nagata, K.

1991-01-01

This invention relates to a building having a floor-by-floor electromagnetic shield structure well-suited for application to an information network system in which an electromagnetically shielded space is divided by individual floors and electric waves are utilized within the building on a floor-by-floor basis. (author). 8 figs

Building with electromagnetic shield structure for individual floors

Energy Technology Data Exchange (ETDEWEB)

Takahashi, T; Nakamura, M; Yabana, Y; Ishikawa, T; Nagata, K

1991-09-10

This invention relates to a building having a floor-by-floor electromagnetic shield structure well-suited for application to an information network system in which an electromagnetically shielded space is divided by individual floors and electric waves are utilized within the building on a floor-by-floor basis. (author). 8 figs.

Carbon fiber reinforced hierarchical orthogrid stiffened cylinder: Fabrication and testing

Science.gov (United States)

Wu, Hao; Lai, Changlian; Sun, Fangfang; Li, Ming; Ji, Bin; Wei, Weiyi; Liu, Debo; Zhang, Xi; Fan, Hualin

2018-04-01

To get strong, stiff and light cylindrical shell, carbon fiber reinforced hierarchical orthogrid stiffened cylinders are designed and fabricated. The cylinder is stiffened by two-scale orthogrid. The primary orthogrid has thick and high ribs and contains several sub-orthogrid cells whose rib is much thinner and lower. The primary orthogrid stiffens the bending rigidity of the cylinder to resist the global instability while the sub-orthogrid stiffens the bending rigidity of the skin enclosed by the primary orthogrid to resist local buckling. The cylinder is fabricated by filament winding method based on a silicone rubber mandrel with hierarchical grooves. Axial compression tests are performed to reveal the failure modes. With hierarchical stiffeners, the cylinder fails at skin fracture and has high specific strength. The cylinder will fail at end crushing if the end of the cylinder is not thickened. Global instability and local buckling are well restricted by the hierarchical stiffeners.

A characteristic analysis of the fluidic muscle cylinder

Science.gov (United States)

Kim, Dong-Soo; Bae, Sang-Kyu; Hong, Sung-In

2005-12-01

The fluidic muscle cylinder consists of an air bellows tube, flanges and lock nuts. It's features are softness of material and motion, simplicity of structure, low production cost and high power efficiency. Recently, unlikely the pneumatic cylinder, the fluidic muscle cylinder without air leakage, stick slip, friction, and seal was developed as a new concept actuator. It has the characteristics such as light weight, low price, high response, durable design, long life, high power, high contraction, which is innovative product fulfilling RT(Robot Technology) which is one of the nation-leading next generation strategy technologies 6T as well as cleanness technology. The application fields of the fluidic muscle cylinder are so various like fatigue tester, brake, accelerator, high technology testing device such as driving simulator, precise position, velocity, intelligent servo actuator under special environment such as load controlling system, and intelligent robot. In this study, we carried out the finite element modeling and analysis about the main design variables such as contraction ration and force, diameter increment of fluidic muscle cylinder. On the basis of finite element analysis, the prototype of fluidic muscle cylinder was manufactured and tested. Finally, we compared the results between the test and the finite element analysis.

Beating motion of a circular cylinder in vortex-induced vibrations

Science.gov (United States)

Shen, Linwei; Chan, Eng-Soon; Wei, Yan

2018-04-01

In this paper, beating phenomenon of a circular cylinder in vortex-induced vibration is studied by numerical simulations in a systematic manner. The cylinder mass coefficients of 2 and 10 are considered, and the Reynolds number is 150. Two distinctive frequencies, namely cylinder oscillation and vortex shedding frequencies, are obtained from the harmonic analysis of the cylinder displacement. The result is consistent with that observed in laboratory experiments. It is found that the cylinder oscillation frequency changes with the natural frequency of the cylinder while the reduced velocity is varied. The added-mass coefficient of the cylinder in beating motion is therefore estimated. Meanwhile, the vortex shedding frequency does not change dramatically in the beating situations. In fact, it is very close to 0.2. Accordingly, the lift force coefficient has two main components associated with these two frequencies. Besides, higher harmonics of the cylinder oscillation frequency appear in the spectrum of the lift coefficient. Moreover, the vortex shedding timing is studied in the beating motion by examining the instantaneous flow fields in the wake, and two scenarios of the vortex formation are observed.

Inflation of polymer melts into elliptic and circular cylinders

DEFF Research Database (Denmark)

Rasmussen, Henrik Koblitz; Christensen, Jens Horslund; Gøttsche, Søren

2000-01-01

A thin sheet (membrane) of the polymeric material is clamped between a Teflon-coated thermostated plate and a thermostated aluminium cylinder. By applying thermostated air through the plate, the polymer membrane deforms into an elliptic or a circular cylinder. The position of the top of the infla......A thin sheet (membrane) of the polymeric material is clamped between a Teflon-coated thermostated plate and a thermostated aluminium cylinder. By applying thermostated air through the plate, the polymer membrane deforms into an elliptic or a circular cylinder. The position of the top...

Electromagnetic forces on type-II superconducting rotating cylinders

International Nuclear Information System (INIS)

Saif, A.G.; Refai, T.F.; El-Sabagh, M.A.

1995-01-01

Analytical solutions of the electromagnetic fields are presented for a system composed of an infinitely long superconducting cylinder rotating about its axis and placed parallel to two infinitely long normal conducting wires. Both wires carry the same alternating current. From the obtained electromagnetic fields the electromagnetic power loss on the cylinder surface, electromagnetic forces due to induced currents, electromagnetic torque, and the work opposing the rotation of the cylinder are calculated. (orig.)

Flow induced by a skewed vortex cylinder

DEFF Research Database (Denmark)

Branlard, Emmanuel Simon Pierre

2017-01-01

The velocity field induced by a skewed vortex cylinder of longitudinal and tangential vorticity is derived in this chapter by direct integration of the Biot– Savart law. The derivation steps are provided in details. The results of Castles and Durham for the skewed semi-infinite cylinder....... The content of this chapter is based on the publication of the author entitled "Cylindrical vortex wake model: skewed cylinder, application to yawed or tilted rotors" [1]. Results from this chapter are applied: in Chap. 21 to model a wind turbine (or rotor) in yaw, in Chap. 22 to derive a new yaw...

Oscillatory Stokes Flow Past a Slip Cylinder

Science.gov (United States)

Palaniappan, D.

2013-11-01

Two-dimensional transient slow viscous flow past a circular cylinder with Navier slip boundary conditions is considered in the limit of low-Reynolds number. The oscillatory Stokes flow problem around a cylinder is solved using the stream function method leading to an analytic solution in terms of modified Bessel functions of the second kind. The corresponding steady-state behavior yields the familiar paradoxical result first detected by Stokes. It is noted that the two key parameters, viz., the frequency λ, and the slip coefficient ξ have a significant impact on the flow field in the vicinity of the cylinder contour. In the limit of very low frequency, the flow is dominated by a term containing a well-known biharmonic function found by Stokes that has a singular behavior at infinity. Local streamlines for small times show interesting flow patterns. Attached eddies due to flow separation - observed in the no-slip case - either get detached or pushed away from the cylinder surface as ξ is varied. Computed asymptotic results predict that the flow exhibits inviscid behavior far away from the cylinder in the frequency range 0 < λ << 1 . Although the frequency of oscillations is finite, our exact solutions reveal fairly rapid transitions in the flow domain. Research Enhancement grant, TAMUCC.

Prediction of external corrosion for steel cylinders

International Nuclear Information System (INIS)

Lyon, B.F.

1997-02-01

The US Department of Energy (DOE) currently manages the UF 6 Cylinder Program (the program). The program was formed to address the depleted-uranium hexafluoride (UF 6 ) stored in approximately 50,000 carbon steel cylinders. The cylinders are located at three DOE sites: the K-25 site (K-25) at Oak Ridge, Tennessee; the Paducah Gaseous Diffusion Plant (PGDP) in Paducah, Kentucky, and the Portsmouth Gaseous Diffusion Plant (PORTS) in Portsmouth, Ohio. The System Requirements Document (SRD) (LMES 1996a) delineates the requirements of the program. The appropriate actions needed to fulfill these requirements are then specified within the System Engineering Management Plan (SEMP) (LMES 1996b). The report presented herein documents activities that in whole or in part satisfy specific requirements and actions stated in the UF 6 Cylinder Program SRD and SEMP with respect to forecasting cylinder conditions. The wall thickness projections made in this report are based on the assumption that the corrosion trends noted will continue. Some activities planned may substantially reduce the rate of corrosion, in which case the results presented here are conservative. The results presented here are intended to supersede those presented previously, as the quality of several of the datasets has improved

Recycling-oriented characterization of small waste electrical and electronic equipment

International Nuclear Information System (INIS)

Chancerel, Perrine; Rotter, Susanne

2009-01-01

As a result of the continuous change in the design and function of consumer electrical and electronic products, the mechanical and material properties of the obsolete products, called waste electric and electronic equipment (WEEE), are highly variable. The variability within WEEE is explained by the number of different appliances, and the heterogeneity in composition of any given appliance. This paper reports on an extended investigation of the properties of WEEE, in particular small appliances. The investigation focuses on the analysis of the composition of about 700 single appliances. Firstly, analytical methods to characterize the waste equipment are described. The results of the experimental analyses show that the mechanical properties, the material composition, the polymer composition and the chemical composition of WEEE vary not only between equipment types with different functions, but also between single appliances within one equipment type. Data on hazardous and valuable substances in selected equipment types are presented. Using detailed data on the composition of individual appliances to calculate rates of recovery for assumed recycling processes demonstrates that the performance of recycling processes depends strongly on the composition of WEEE. Recycling-oriented characterization is, therefore, a systematic approach to support the design and the operation of recycling processes.

Vortex structure behind highly heated two cylinders in parallel arrangements

International Nuclear Information System (INIS)

Kurita, Eiichirou; Yahagi, Yuji

2008-01-01

Vortex structures behind twin, highly heated cylinders in parallel arrangements have been investigated experimentally. The experiments were conducted under the following conditions: cylinder diameter, D=4 mm; mean flow velocity, U ∞ =1.0 m/s; Reynolds number, Re=250; cylinder clearance, S/D=0.5 - 1.4; and cylinder heat flux, q=0 - 72.6 kW/m 2 . For S/D > 1.2, the Karman vortex street is formed alternately behind each cylinder divided on the slit flow. The slit flow velocity increases with a decrease in S/D and decreases with increasing heat flux. For S/D 2 ). As a result, the increased local kinematic viscosity and S/D play a key role for the vortex structure and formation behind arrangements of two parallel cylinders. (author)

Controlling chaos in a fluid flow past a movable cylinder

International Nuclear Information System (INIS)

Vallejo, Juan C.; Marino, Ines P.; Sanjuan, Miguel A.F.; Kurths, Juergen

2003-01-01

The model of a two-dimensional fluid flow past a cylinder is a relatively simple problem with a strong impact in many applied fields, such as aerodynamics or chemical sciences, although most of the involved physical mechanisms are not yet well known. This paper analyzes the fluid flow past a cylinder in a laminar regime with Reynolds number, Re, around 200, where two vortices appear behind the cylinder, by using an appropriate time-dependent stream function and applying non-linear dynamics techniques. The goal of the paper is to analyze under which circumstances the chaoticity in the wake of the cylinder might be modified, or even suppressed. And this has been achieved with the help of some indicators of the complexity of the trajectories for the cases of a rotating cylinder and an oscillating cylinder

76 FR 55736 - Safety Advisory: Unauthorized Marking of Compressed Gas Cylinders

Science.gov (United States)

2011-09-08

... certain of high- and low-pressure compressed gas cylinders, primarily fire extinguishers, by Atlas Fire...- pressure cylinders serviced by Atlas Fire Protection were marked and represented as requalified (visually... damage, serious personal injury, or death could result from the rupture of a cylinder. Cylinders not...

The Passive Neutron Enrichment Meter for Uranium Cylinder Assay

Energy Technology Data Exchange (ETDEWEB)

Miller, Karen A.; Menlove, Howard O.; Swinhoe, Martyn T.; Marlow, Johanna B. [Safeguards Science and Technology Group (N-1), Los Alamos National Laboratory, Los Alamos (United States)

2011-12-15

As fuel cycle technology becomes more prevalent around the world, international safeguards have become increasingly important in verifying that nuclear materials have not been diverted. Uranium enrichment technology is a critical pathway to nuclear weapons development, making safeguards of enrichment facilities especially important. Independently-verifiable material accountancy is a fundamental measure in detecting diversion of nuclear materials. This paper is about a new instrument for uranium cylinder assay for enrichment plant safeguards called the Passive Neutron Enrichment Meter (PNEM). The measurement objective is to simultaneously verify uranium mass and enrichment in Uf6 cylinders. It can be used with feed, product, and tails cylinders. Here, we consider the enrichment range up to 5% {sup 235}U. The concept is to use the Doubles-to-Singles count rate to give a measure of the {sup 235}U enrichment and the Singles count rate to provide a measure of the total uranium mass. The cadmium ratio is an additional signature for the enrichment that is especially useful for feed and tails cylinders. PNEM is a {sup 3}He-based system that consists of two portable detector pods. Uranium enrichment in UF{sub 6} cylinders is typically determined using a gamma-ray-based method that only samples a tiny volume of the cylinder's content and requires knowledge of the cylinder wall thickness. The PNEM approach has several advantages over gamma-ray-based methods including a deeper penetration depth into the cylinder, meaning it can be used with heterogeneous isotopic mixtures of UF{sub 6}. In this paper, we describe a Monte Carlo modelling study where we have examined the sensitivity of the system to systematic uncertainties such as the distribution of UF{sub 6} within the cylinder. We also compare characterization measurements of the PNEM prototype to the expected measurements calculated with Monte Carlo simulations.

Steady particulate flows in a horizontal rotating cylinder

Science.gov (United States)

Yamane, K.; Nakagawa, M.; Altobelli, S. A.; Tanaka, T.; Tsuji, Y.

1998-06-01

Results of discrete element method (DEM) simulation and magnetic resonance imaging (MRI) experiments are compared for monodisperse granular materials flowing in a half-filled horizontal rotating cylinder. Because opacity is not a problem for MRI, a long cylinder with an aspect ratio ˜7 was used and the flow in a thin transverse slice near the center was studied. The particles were mustard seeds and the ratio of cylinder diameter to particle diameter was approximately 50. The parameters compared were dynamic angle of repose, velocity field in a plane perpendicular to the cylinder axis, and velocity fluctuations at rotation rates up to 30 rpm. The agreement between DEM and MRI was good when the friction coefficient and nonsphericity were adjusted in the simulation for the best fit.

Flooring choices for newborn ICUs.

Science.gov (United States)

White, R D

2007-12-01

Floors are a major element of newborn intensive care unit (NICU) construction. They provide visual cues, sound control, and with certain materials, some degree of physical comfort for workers. Flooring materials may entail a significant cost for installation and upkeep and can have substantial ecological impact, both in the choice of the flooring itself, as well as the substances used to clean it. In this article the important aspects to consider for each factor are explored and recommendations are offered for appropriate choices in various NICU areas.

Proximity functions for general right cylinders

International Nuclear Information System (INIS)

Kellerer, A.M.

1981-01-01

Distributions of distances between pairs of points within geometrical objects, or the closely related proximity functions and geometric reduction factors, have applications to dosimetric and microdosimetric calculations. For convex bodies these functions are linked to the chord-length distributions that result from random intersections by straight lines. A synopsis of the most important relations is given. The proximity functions and related functions are derived for right cylinders with arbitrary cross sections. The solution utilizes the fact that the squares of the distances between two random points are sums of independently distributed squares of distances parallel and perpendicular to the axis of the cylinder. Analogous formulas are derived for the proximity functions or geometric reduction factors for a cylinder relative to a point. This requires only a minor modification of the solution

ROBUST CYLINDER FITTING IN THREE-DIMENSIONAL POINT CLOUD DATA

Directory of Open Access Journals (Sweden)

A. Nurunnabi

2017-05-01

Full Text Available This paper investigates the problems of cylinder fitting in laser scanning three-dimensional Point Cloud Data (PCD. Most existing methods require full cylinder data, do not study the presence of outliers, and are not statistically robust. But especially mobile laser scanning often has incomplete data, as street poles for example are only scanned from the road. Moreover, existence of outliers is common. Outliers may occur as random or systematic errors, and may be scattered and/or clustered. In this paper, we present a statistically robust cylinder fitting algorithm for PCD that combines Robust Principal Component Analysis (RPCA with robust regression. Robust principal components as obtained by RPCA allow estimating cylinder directions more accurately, and an existing efficient circle fitting algorithm following robust regression principles, properly fit cylinder. We demonstrate the performance of the proposed method on artificial and real PCD. Results show that the proposed method provides more accurate and robust results: (i in the presence of noise and high percentage of outliers, (ii for incomplete as well as complete data, (iii for small and large number of points, and (iv for different sizes of radius. On 1000 simulated quarter cylinders of 1m radius with 10% outliers a PCA based method fit cylinders with a radius of on average 3.63 meter (m; the proposed method on the other hand fit cylinders of on average 1.02 m radius. The algorithm has potential in applications such as fitting cylindrical (e.g., light and traffic poles, diameter at breast height estimation for trees, and building and bridge information modelling.

Simulations of floor cooling system capacity

International Nuclear Information System (INIS)

Odyjas, Andrzej; Górka, Andrzej

2013-01-01

Floor cooling system capacity depends on its physical and operative parameters. Using numerical simulations, it appears that cooling capacity of the system largely depends on the type of cooling loads occurring in the room. In the case of convective cooling loads capacity of the system is small. However, when radiation flux falls directly on the floor the system significantly increases productivity. The article describes the results of numerical simulations which allow to determine system capacity in steady thermal conditions, depending on the type of physical parameters of the system and the type of cooling load occurring in the room. Moreover, the paper sets out the limits of system capacity while maintaining a minimum temperature of the floor surface equal to 20 °C. The results are helpful for designing system capacity in different type of cooling loads and show maximum system capacity in acceptable thermal comfort condition. -- Highlights: ► We have developed numerical model for simulation of floor cooling system. ► We have described floor system capacity depending on its physical parameters. ► We have described floor system capacity depending on type of cooling loads. ► The most important in the obtained cooling capacities is the type of cooling loads. ► The paper sets out the possible maximum cooling floor system capacity

An experiments and characteristics analysis of the sealless cylinder

International Nuclear Information System (INIS)

Kim, Young Cheol; Kim, Dong Soo; Bae, Sang Kyu; Kim, Sung Jong

2004-01-01

This paper shows a performance analysis for conical type sealless cylinders and rod bearings. The pistons without seal have partly cylindrical and conical shapes. 2 dimensional Reynolds equation and FD(Finite Differential) numerical techniques are utilized for the performance analysis. The relationship among self-centering forces and leakage flows are investigated. Also, optimal design values for a sealless cylinder are presented. A prototype of sealless cylinder which had rod bearing with four pockets, five pockets, and six pockets was manufactured respectively. Leakage flow test is conducted to evaluate performance of piston and rod bearing in sealless cylinder

EFFECTIVE KEYED CONNECTIONS OF HOLLOW-CORE FLOOR SLABS WITH WALLS IN MODERN LARGE-PANEL HOUSE BUILDING

Directory of Open Access Journals (Sweden)

O. A. Dovzhenko

2018-01-01

Full Text Available The paper considers large-panel constructive system of multi-storey buildings and its industrial basis creates conditions for intensive volume growth in house construction. Application of hollow-core panels are recommended as floor slabs that allows to increase a distance between bearing walls, to improve planning solutions, and also significantly to increase thermal and sound protection properties of floor discs (coatings. Keyed joints having the highest resistance to shearing forces are used to ensure joint action of the slabs with wall panels. A supporting unit of floor elements in the precast-monolithic constructive system ARKOS by means of concrete keys is considered as a prototype of the considered joint. In order to increase a bearing capacity and improve reliability of joints it is envisaged to reinforce keys with space frames. Improvement of joint units is possible to carry out with due account of total number of the factors influencing on strength. Poltava National Technical University named after Yuri Kondratyuk has developed a general methodology for assessment of bearing capacity in keyed joints which is based on the variational method in the theory of concrete plasticity and reflects specificity of stress-strain state of the failure zone. For experimental verification of this methodology investigations have been carried out with the purpose to test operation of keys when they are reinforced in mid-height and reinforcement is distributed in two tiers. The observed experimental fracture pattern in the specimens has confirmed kinematic schemes accepted for calculations and comparative analysis of experimental and theoretical values points to their closeness. Two-level reinforcement significantly improves plastic properties of concrete keys and excludes brittle failure. The proposed design of the joint unit for floor slabs with wall panels is characterized by the ratio of key dimensions and shape of reinforcing cages in the form of

Direct adaptive fuzzy control of a translating piezoelectric flexible manipulator driven by a pneumatic rodless cylinder

Science.gov (United States)

Qiu, Zhi-cheng; Wang, Bin; Zhang, Xian-min; Han, Jian-da

2013-04-01

This study presents a novel translating piezoelectric flexible manipulator driven by a rodless cylinder. Simultaneous positioning control and vibration suppression of the flexible manipulator is accomplished by using a hybrid driving scheme composed of the pneumatic cylinder and a piezoelectric actuator. Pulse code modulation (PCM) method is utilized for the cylinder. First, the system dynamics model is derived, and its standard multiple input multiple output (MIMO) state-space representation is provided. Second, a composite proportional derivative (PD) control algorithms and a direct adaptive fuzzy control method are designed for the MIMO system. Also, a time delay compensation algorithm, bandstop and low-pass filters are utilized, under consideration of the control hysteresis and the caused high-frequency modal vibration due to the long stroke of the cylinder, gas compression and nonlinear factors of the pneumatic system. The convergence of the closed loop system is analyzed. Finally, experimental apparatus is constructed and experiments are conducted. The effectiveness of the designed controllers and the hybrid driving scheme is verified through simulation and experimental comparison studies. The numerical simulation and experimental results demonstrate that the proposed system scheme of employing the pneumatic drive and piezoelectric actuator can suppress the vibration and achieve the desired positioning location simultaneously. Furthermore, the adopted adaptive fuzzy control algorithms can significantly enhance the control performance.

Magnetic susceptibility in the edged topological disordered nanoscopic cylinder

International Nuclear Information System (INIS)

Faizabadi, Edris; Omidi, Mahboubeh

2011-01-01

The effects of edged topological disorder on magnetic susceptibility are investigated in a nanoscopic cylinder threaded by a magnetic flux. Persistent current versus even or odd number of electrons shows different signs in ordered and disordered cylinders and also in short or long ones. In addition, temperature-averaged susceptibility has only diamagnetic signs in strong regimes and it is associated with paramagnetic signs in ordered and weak disordered ones. Besides, in an edged topological disordered cylinder, the temperature-averaged susceptibility decreases by raising the temperature somewhat and then increasing initiates and finally at high temperature tends to zero as the ordered one. - Research highlights: → Magnetic susceptibility in one-dimensional topological disordered quantum ring. → Edged topological disorder effect on magnetic susceptibility in nanoscopic cylinder. → Edged topological disorder effect on temperature-averaged susceptibility in cylinder.

Formaldehyde and TVOC emission behavior of laminate flooring by structure of laminate flooring and heating condition.

Science.gov (United States)

An, Jae-Yoon; Kim, Sumin; Kim, Hyun-Joong

2011-03-15

Formaldehyde was measured with a desiccator, a 20 L chamber and the FLEC method. The formaldehyde emission rate from laminate was the highest at 32 °C using the desiccator, which then decreased with time. The formaldehyde emission using the 20 L small chamber and FLEC showed a similar tendency. There was a strong correlation between the formaldehyde and total volatile organic compounds (TVOCs) with both types of floorings using the two different methods. The formaldehyde emission rate and TVOC results were higher when tested using the FLEC method than with the 20 L small chamber method. The emission rate was affected by the joint edge length in laminate flooring. Toluene, ethylbenzene and xylene were the main VOCs emitted from laminate flooring, and there were more unidentified VOCs emitted than identified VOCs. The samples heated with a floor heating system emitted more formaldehyde than those heated using an air circulation system due to the temperature difference between the bottom panel and flooring. The TVOC emission level of the samples was higher when an air circulation system was used than when a floor heating system was used due to the high ventilation rate. Copyright © 2010 Elsevier B.V. All rights reserved.

Dynamical instability of a charged gaseous cylinder

Science.gov (United States)

Sharif, M.; Mumtaz, Saadia

2017-10-01

In this paper, we discuss dynamical instability of a charged dissipative cylinder under radial oscillations. For this purpose, we follow the Eulerian and Lagrangian approaches to evaluate linearized perturbed equation of motion. We formulate perturbed pressure in terms of adiabatic index by applying the conservation of baryon numbers. A variational principle is established to determine characteristic frequencies of oscillation which define stability criteria for a gaseous cylinder. We compute the ranges of radii as well as adiabatic index for both charged and uncharged cases in Newtonian and post-Newtonian limits. We conclude that dynamical instability occurs in the presence of charge if the gaseous cylinder contracts to the radius R*.

Prediction model of velocity field around circular cylinder over various Reynolds numbers by fusion convolutional neural networks based on pressure on the cylinder

Science.gov (United States)

Jin, Xiaowei; Cheng, Peng; Chen, Wen-Li; Li, Hui

2018-04-01

A data-driven model is proposed for the prediction of the velocity field around a cylinder by fusion convolutional neural networks (CNNs) using measurements of the pressure field on the cylinder. The model is based on the close relationship between the Reynolds stresses in the wake, the wake formation length, and the base pressure. Numerical simulations of flow around a cylinder at various Reynolds numbers are carried out to establish a dataset capturing the effect of the Reynolds number on various flow properties. The time series of pressure fluctuations on the cylinder is converted into a grid-like spatial-temporal topology to be handled as the input of a CNN. A CNN architecture composed of a fusion of paths with and without a pooling layer is designed. This architecture can capture both accurate spatial-temporal information and the features that are invariant of small translations in the temporal dimension of pressure fluctuations on the cylinder. The CNN is trained using the computational fluid dynamics (CFD) dataset to establish the mapping relationship between the pressure fluctuations on the cylinder and the velocity field around the cylinder. Adam (adaptive moment estimation), an efficient method for processing large-scale and high-dimensional machine learning problems, is employed to implement the optimization algorithm. The trained model is then tested over various Reynolds numbers. The predictions of this model are found to agree well with the CFD results, and the data-driven model successfully learns the underlying flow regimes, i.e., the relationship between wake structure and pressure experienced on the surface of a cylinder is well established.

Mechanical Integrity of Copper Canister Lid and Cylinder. Sensitivity study

International Nuclear Information System (INIS)

Karlsson, Marianne

2002-08-01

This report is part of a study of the mechanical integrity of canisters used for disposal of nuclear fuel waste. The overall objective is to determine and ensure the static and long-term strength of the copper canister lid and cylinder casing. The canisters used for disposal nuclear fuel waste of type BWR consists of an inner part (insert) of ductile cast iron and an outer part of copper. The copper canister is to provide a sealed barrier between the contents of the canister and the surroundings. The study in this report complements the finite element analyses performed in an earlier study. The analyses aim to evaluate the sensitivity of the canister to tolerances regarding the gap between the copper cylinder and the cast iron insert. Since great uncertainties regarding the material's long term creep properties prevail, analyses are also performed to evaluate the effect of different creep data on the resulting strain and stress state. The report analyses the mechanical response of the lid and flange of the copper canister when subjected to loads caused by pressure from swelling bentonite and from groundwater at a depth of 500 meter. The loads acting on the canister are somewhat uncertain and the cases investigated in this report are possible cases. Load cases analysed are: Pressure 15 MPa uniformly distributed on lid and 5 MPa uniformly distributed on cylinder; Pressure 5 MPa uniformly distributed on lid and 15 MPa uniformly distributed on cylinder; Pressure 20 MPa uniformly distributed on lid and cylinder; and Side pressures 10 MPa and 20 MPa uniformly distributed on part of the cylinder. Creep analyses are performed for two of the load cases. For all considered designs high principal stresses appear on the outside of the copper cylinder in the region from the weld down to the level of the lid lower edge. Altering the gap between lid and cylinder and/or between cylinder and insert only marginally affects the resulting stress state. Fitting the lid in the cylinder

Evaluation of Concrete Cylinder Tests Using Finite Elements

DEFF Research Database (Denmark)

Saabye Ottosen, Niels

1984-01-01

Nonlinear axisymmetric finite element analyses are performed on the uniaxial compressive test of concrete cylinders. The models include thick steel loading plates, and cylinders with height‐to‐diameter ratios (h/d) ranging from 1‐3 are treated. A simple constitutive model of the concrete is emplo......Nonlinear axisymmetric finite element analyses are performed on the uniaxial compressive test of concrete cylinders. The models include thick steel loading plates, and cylinders with height‐to‐diameter ratios (h/d) ranging from 1‐3 are treated. A simple constitutive model of the concrete...... uniaxial strength the use of geometrically matched loading plates seems to be advantageous. Finally, it is observed that for variations of the element size within limits otherwise required to obtain a realistic analysis, the results are insensitive to the element size....

Crustal Ages of the Ocean Floor - Poster

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The Crustal Ages of the Ocean Floor Poster was created at NGDC using the Crustal Ages of the Ocean Floor database draped digitally over a relief of the ocean floor...

A Convenient Storage Rack for Graduated Cylinders

Science.gov (United States)

Love, Brian

2004-01-01

An attempt is made to find a solution to the occasional problem of a need for storing large numbers of graduated cylinders in many teaching and research laboratories. A design, which involves the creation of a series of parallel channels that are used to suspend inverted graduated cylinders by their bases, is proposed.

Damping analysis of cylindrical composite structures with enhanced viscoelastic properties

DEFF Research Database (Denmark)

Kliem, Mathias; Høgsberg, Jan Becker; Vanwalleghem, Joachim

2018-01-01

is forced to deform in shear mode. Thus, the vibration energy is dissipated as low grade frictional heat. This paper documents the efficiency of passive constrained layer damping treatments for low frequency vibrations of cylindrical composite specimens made of glass fibre-reinforced plastics. Different cross...... section geometries with shear webs have been investigated in order to study a beneficial effect on the damping characteristics of the cylinder. The viscoelastic damping layers are placed at different locations within the composite cylinder e.g. circumferential and along the neutral plane to evaluate...... in the neutral plane perpendicular to the bending load. The results are based on free decay tests of the composite structure....

A constant-density Gurney approach to the Cylinder test

Energy Technology Data Exchange (ETDEWEB)

Reaugh, John E.; Souers, P. Clark [Energetic Materials Center, Lawrence Livermore National Laboratory, Livermore, CA 94550 (United States)

2004-04-01

The previous analysis of the Cylinder test required the treatment of different wall thicknesses and wall materials separately. To fix this, the Gurney analysis is used, but this results in low values for full-wall standard, ideal explosives relative to CHEETAH analyses. A new constant metal-density model is suggested, which takes account of the thinning metal wall as the cylinder expands. With this model, the inner radius of the metal cylinder moves faster than the measured outer radius. Additional small corrections occur in all cylinders because of energy trapped in the copper walls. Also, the half-wall cylinders have a small correction because the relative volumes of the gas products are smaller at a given outside wall displacement. The Fabry-Perot and streak camera measurements are compared. The Fabry method is shown to equate to the constant density model. (Abstract Copyright [2004], Wiley Periodicals, Inc.)

Replication of engine block cylinder bridge microstructure and mechanical properties with lab scale 319 Al alloy billet castings

International Nuclear Information System (INIS)

Lombardi, A.; D'Elia, F.; Ravindran, C.; MacKay, R.

2014-01-01

In recent years, aluminum alloy gasoline engine blocks have in large part successfully replaced nodular cast iron engine blocks, resulting in improved vehicle fuel efficiency. However, because of the inadequate wear resistance properties of hypoeutectic Al–Si alloys, gray iron cylinder liners are required. These liners cause the development of large tensile residual stress along the cylinder bores and necessitate the maximization of mechanical properties in this region to prevent premature engine failure. The aim of this study was to replicate the engine cylinder bridge microstructure and mechanical properties following TSR treatment (which removes the sand binder to enable easy casting retrieval) using lab scale billet castings of the same alloy composition with varying cooling rates. Comparisons in microstructure between the engine block and the billet castings were carried out using optical and scanning electron microscopy, while mechanical properties were assessed using tensile testing. The results suggest that the microstructure at the top and middle of the engine block cylinder bridge was successfully replicated by the billet castings. However, the microstructure at the bottom of the cylinder was not completely replicated due to variations in secondary phase morphology and distribution. The successful replication of engine block microstructure will enable the future optimization of heat treatment parameters. - Highlights: • A method to replicate engine block microstructure was developed. • Billet castings will allow cost effective optimization of heat treatment process. • The replication of microstructure in the cylinder region was mostly successful. • Porosity was more clustered in the billet castings compared to the engine block. • Mechanical properties were lower in billet castings due to porosity and inclusions

Replication of engine block cylinder bridge microstructure and mechanical properties with lab scale 319 Al alloy billet castings

Energy Technology Data Exchange (ETDEWEB)

Lombardi, A., E-mail: a2lombar@ryerson.ca [Centre for Near-net-shape Processing of Materials, Ryerson University, 101 Gerrard Street East, Toronto, Ontario M5B2K3 (Canada); D' Elia, F.; Ravindran, C. [Centre for Near-net-shape Processing of Materials, Ryerson University, 101 Gerrard Street East, Toronto, Ontario M5B2K3 (Canada); MacKay, R. [Nemak of Canada Corporation, 4600 G.N. Booth Drive, Windsor, Ontario N9C4G8 (Canada)

2014-01-15

In recent years, aluminum alloy gasoline engine blocks have in large part successfully replaced nodular cast iron engine blocks, resulting in improved vehicle fuel efficiency. However, because of the inadequate wear resistance properties of hypoeutectic Al–Si alloys, gray iron cylinder liners are required. These liners cause the development of large tensile residual stress along the cylinder bores and necessitate the maximization of mechanical properties in this region to prevent premature engine failure. The aim of this study was to replicate the engine cylinder bridge microstructure and mechanical properties following TSR treatment (which removes the sand binder to enable easy casting retrieval) using lab scale billet castings of the same alloy composition with varying cooling rates. Comparisons in microstructure between the engine block and the billet castings were carried out using optical and scanning electron microscopy, while mechanical properties were assessed using tensile testing. The results suggest that the microstructure at the top and middle of the engine block cylinder bridge was successfully replicated by the billet castings. However, the microstructure at the bottom of the cylinder was not completely replicated due to variations in secondary phase morphology and distribution. The successful replication of engine block microstructure will enable the future optimization of heat treatment parameters. - Highlights: • A method to replicate engine block microstructure was developed. • Billet castings will allow cost effective optimization of heat treatment process. • The replication of microstructure in the cylinder region was mostly successful. • Porosity was more clustered in the billet castings compared to the engine block. • Mechanical properties were lower in billet castings due to porosity and inclusions.

Investigation on carbon nanomaterials: Coaxial CNT-cylinders and ...

Indian Academy of Sciences (India)

Wintec

carbon cylinders of CNT stacks have been formed directly inside the quartz tube. Another study is ... producing CNTs have been devised including electric arc evaporation ... process of coaxial carbon cylinder have already been de- scribed by ...

75 FR 66126 - Multilayered Wood Flooring From China

Science.gov (United States)

2010-10-27

...)] Multilayered Wood Flooring From China AGENCY: United States International Trade Commission. ACTION: Institution... flooring, provided for in subheadings 4409.10, 4409.29, 4412.31, 4412.32, 4412.39, 4412.94, 4412.99, 4418... multilayered wood flooring. The following companies are members of the CAHP: Anderson Hardwood Floors, LLC...

75 FR 79019 - Multilayered Wood Flooring From China

Science.gov (United States)

2010-12-17

...)] Multilayered Wood Flooring From China Determinations On the basis of the record \\1\\ developed in the subject... imports from China of multilayered wood flooring, provided for in subheadings 4409.10, 4409.29, 4412.31... multilayered wood flooring. The following companies are members of the CAHP: Anderson Hardwood Floors, LLC...

Mode of delivery and Pelvic floor disorder

International Nuclear Information System (INIS)

Noor, R.; Neelam, H.; Bashir, M.S.

2017-01-01

Objective: To compare pelvic floor dysfunction in non pregnant women who had delivered vaginally versus those with cesarean delivery. Methodology: The prevalence of pelvic floor disorders among non pregnant women was assesses by using a standardized tool pelvic floor distress inventory short form (PFDI-20). Data was collected from Jinnah Hospital Lahore, Pakistan. Results: Total numbers of participants were 278. 47.12% subjects had moderate, 36.69% miner and 16.19% had severe pelvic floor dysfunction. The symptoms of pelvic organ prolapse were more prevalent (mean value is 59.1876) than Urinary Distress (mean value is 40.5426), while the Colorectal-Anal Distress (mean value is 35.9150) were least prevalent. Conclusion: Pelvic floor disorders are very common among females and are strongly associated with mode of delivery. Although spontaneous vaginal birth was extensively associated with pelvic floor disorders the instrumental delivery affects most. (author)

Adaptive individual-cylinder thermal state control using piston cooling for a GDCI engine

Science.gov (United States)

Roth, Gregory T; Husted, Harry L; Sellnau, Mark C

2015-04-07

A system for a multi-cylinder compression ignition engine includes a plurality of nozzles, at least one nozzle per cylinder, with each nozzle configured to spray oil onto the bottom side of a piston of the engine to cool that piston. Independent control of the oil spray from the nozzles is provided on a cylinder-by-cylinder basis. A combustion parameter is determined for combustion in each cylinder of the engine, and control of the oil spray onto the piston in that cylinder is based on the value of the combustion parameter for combustion in that cylinder. A method for influencing combustion in a multi-cylinder engine, including determining a combustion parameter for combustion taking place in in a cylinder of the engine and controlling an oil spray targeted onto the bottom of a piston disposed in that cylinder is also presented.

Prediction of External Corrosion for Steel Cylinders--2002 Report

International Nuclear Information System (INIS)

Schmoyer, RLS

2002-01-01

The United States Department of Energy (DOE) manages the UF 6 Cylinder Project. The project was formed to maintain and safely manage the depleted uranium hexafluoride (UF 6 ) stored in approximately 50,000 carbon steel cylinders. The cylinders are located at three DOE sites: the East Tennessee Technology Park (ETTP) site in Oak Ridge, Tennessee; the Paducah Gaseous Diffusion Plant (PGDP) in Paducah, Kentucky, and the Portsmouth Gaseous Diffusion Plant (PORTS) in Portsmouth, Ohio. The System Requirements Document (SRD) (LMES 1997a) delineates the requirements of the project, and the actions needed to fulfill these requirements are specified in the System Engineering Management Plan (SEMP) (LMES 1997b). This report documents activities that in whole or part satisfy specific requirements and actions stated in the UF 6 Cylinder Project SRD and SEMP with respect to forecasting cylinder conditions. The results presented here supercede those presented by Lyon (1995, 1996, 1997, 1998, 2000), and Schmoyer and Lyon (2001). Many of the wall thickness projections made in this report are conservative, because they are based on the assumption that corrosion trends will continue, despite activities such as improved monitoring, relocations to better storage, painting, and other improvements in storage conditions relative to the conditions at the times most of the wall thickness measurements were made. For thin-wall cylinders (design nominal wall thickness 312.5 mils), the critical minimum wall thicknesses criteria used in this report are 0 (breach), 62.5 mils, and 250 mils (1 mil = 0.001 in.). For thick-wall cylinders (design nominal wall thickness 625 mils), the thickness criteria used in this report are 0, 62.5 mils, and 500 mils. The criteria triples are preliminary boundaries identified within the project that indicate (1) loss of material (UF 6 ), (2) safe handling and stacking operations, and (3) standards for off-site transport and contents transfer criteria, respectively

Processing of mixed-waste compressed-gas cylinders on the Oak Ridge Reservation

International Nuclear Information System (INIS)

Morris, M.I.; Conley, T.B.; Osborne-Lee, I.W.

1998-03-01

To comply with restrictions on the storage of old compressed gas cylinders, the environmental management organization of Lockheed Martin Energy Systems must dispose of several thousand kilograms of compressed gases stored on the Oak Ridge Reservation (ORR) because the cylinders cannot be taken off-site for disposal in their current configuration. In the ORR Site Treatment Plan, a milestone is cited that requires repackaging and shipment off-site of 21 cylinders by September 30, 1997. A project was undertaken to first evaluate and then either recontainerize or neutralize these cylinders using a transportable compressed gas recontainerization skid (TCGRS), which was developed by Integrated Environmental Services of Atlanta. The transportable system can: (1) sample, analyze, and identify at the site the chemical and radiological content of each cylinder, even those with inoperable valves; (2) breach cylinders, when necessary, to release their contents into a containment chamber; and (3) either neutralize the gas or liquid contents within the containment chamber or transfer the gas or liquids to a new cylinder. The old cylinders and cylinder fragments were disposed of and the gases neutralized or transferred to new cylinders for transportation off-site for disposal. The entire operation to process the 21 cylinders took place in only 5 days once the system was approved for operation. The system performed as expected and can now be used to process the potentially thousands of more cylinders located across the US Department of Energy (DOE) complex that have not yet been declared surplus

Vortex shedding control of circular cylinder by perforated shroud in deep water

Directory of Open Access Journals (Sweden)

Ozkan Gokturk M.

2017-01-01

Full Text Available The aim of the present study is to control the vortex shedding downstream of a circular cylinder (inner cylinder by the existence of outer perforated cylinder concentrically located around the inner cylinder in deep water. The flow characteristics downstream of concentrically placed coupled cylinders were investigated quantitatively by the Particle Image Velocimetry (PIV technique. Diameter of the outer perforated cylinder and inner cylinder were kept constant as Do=100 mm and Di=50 mm. The depth-averaged free-stream velocity was also kept constant as U=100 mm/s which corresponded to the Reynolds number of ReDo=10,000 based on the outer cylinder diameter. Experiments were conducted for six porosities (β = 0.3, 0.4, 0.5, 0.6, 0.7 and 0.8 in order to show the effect of these parameters on the flow control. Maximum values of both Reynolds shear stress, and turbulence kinetic energy, significantly decreased with the existence of outer perforated cylinder and also, the location of peak magnitudes of turbulence statistics occurred at locations further downstream compared to the bare cylinder case. The most effective control was revealed for the porosity of β=0.7.

Vortex shedding control of circular cylinder by perforated shroud in deep water

Science.gov (United States)

Ozkan, Gokturk M.; Durhasan, Tahir; Pinar, Engin; Aksoy, Muhammed M.; Akilli, Huseyin; Sahin, Beşir

The aim of the present study is to control the vortex shedding downstream of a circular cylinder (inner cylinder) by the existence of outer perforated cylinder concentrically located around the inner cylinder in deep water. The flow characteristics downstream of concentrically placed coupled cylinders were investigated quantitatively by the Particle Image Velocimetry (PIV) technique. Diameter of the outer perforated cylinder and inner cylinder were kept constant as Do=100 mm and Di=50 mm. The depth-averaged free-stream velocity was also kept constant as U=100 mm/s which corresponded to the Reynolds number of ReDo=10,000 based on the outer cylinder diameter. Experiments were conducted for six porosities (β = 0.3, 0.4, 0.5, 0.6, 0.7 and 0.8) in order to show the effect of these parameters on the flow control. Maximum values of both Reynolds shear stress, and turbulence kinetic energy, significantly decreased with the existence of outer perforated cylinder and also, the location of peak magnitudes of turbulence statistics occurred at locations further downstream compared to the bare cylinder case. The most effective control was revealed for the porosity of β=0.7.

AFM tip-sample convolution effects for cylinder protrusions

Science.gov (United States)

Shen, Jian; Zhang, Dan; Zhang, Fei-Hu; Gan, Yang

2017-11-01

A thorough understanding about the AFM tip geometry dependent artifacts and tip-sample convolution effect is essential for reliable AFM topographic characterization and dimensional metrology. Using rigid sapphire cylinder protrusions (diameter: 2.25 μm, height: 575 nm) as the model system, a systematic and quantitative study about the imaging artifacts of four types of tips-two different pyramidal tips, one tetrahedral tip and one super sharp whisker tip-is carried out through comparing tip geometry dependent variations in AFM topography of cylinders and constructing the rigid tip-cylinder convolution models. We found that the imaging artifacts and the tip-sample convolution effect are critically related to the actual inclination of the working cantilever, the tip geometry, and the obstructive contacts between the working tip's planes/edges and the cylinder. Artifact-free images can only be obtained provided that all planes and edges of the working tip are steeper than the cylinder sidewalls. The findings reported here will contribute to reliable AFM characterization of surface features of micron or hundreds of nanometers in height that are frequently met in semiconductor, biology and materials fields.

Functional anatomy of pelvic floor

Directory of Open Access Journals (Sweden)

Salvatore Rocca Rossetti

2016-03-01

Full Text Available Generally, descriptions of the pelvic floor are discordant, since its complex structures and the complexity of pathological disorders of such structures; commonly the descriptions are sectorial, concerning muscles, fascial developments, ligaments and so on. On the contrary to understand completely nature and function of the pelvic floor it is necessary to study it in the most unitary view and in the most global aspect, considering embriology, philogenesy, anthropologic development and its multiple activities others than urological, gynaecological and intestinal ones. Recent acquirements succeeded in clarifying many aspects of pelvic floor activity, whose musculature has been investigated through electromyography, sonography, magnetic resonance, histology, histochemistry, molecular research. Utilizing recent research concerning not only urinary and gynecologic aspects but also those regarding statics and dynamics of pelvis and its floor, it is now possible to study this important body part as a unit; that means to consider it in the whole body economy to which maintaining upright position, walking and behavior or physical conduct do not share less than urinary, genital, and intestinal functions. It is today possible to consider the pelvic floor as a musclefascial unit with synergic and antagonistic activity of muscular bundles, among them more or less interlaced, with multiple functions and not only the function of pelvic cup closure.

Effect of Surface Coatings on Cylinders Exposed to Underwater Shock

Directory of Open Access Journals (Sweden)

Y.W. Kwon

1994-01-01

Full Text Available The response of a coated cylinder (metallic cylinder coated with a rubber material subjected to an underwater explosion is analyzed numerically. The dynamic response of the coated cylinder appears to be adversely affected when impacted by an underwater shock wave under certain conditions of geometry and material properties of the coating. When adversely affected, significant deviations in values of axial stress, hoop stress, and strain are observed. The coated cylinder exhibits a larger deformation and higher internal energy in the metallic material. Rubber coatings appeared to inhibit energy dissipation from the metallic material to the surrounding water medium. A parametric study of various coatings was performed on both aluminum and steel cylinders. The adverse effect of the coating decreased when the stiffness of the rubber layer increased, indicating the existence of a threshold value. The results of this study indicate that the stiffness of the coating is a critical factor to the shock hardening of the coated cylinder.

Long-term storage of compressed radioactive krypton in cylinders

International Nuclear Information System (INIS)

Niephaus, D.; Nommensen, O.; Bruecher, H.

1982-01-01

The recommendations of the German Radiation Protection Commission necessitate the separation of the radioactive noble gas krypton-85 (Kr-85) produced in large LWR reprocessing plants from the dissolver off-gas. A possible method of removal is a long-term storage of the compressed noble gas above ground in cylinders. The aim of the present study is to develop such a storage concept and evaluate its feasibility under the aspects of safety and cost. After having been filled, the gas cylinders are placed separately into transport racks serving to protect the cylinders. Following this, the cylinders are transferred out of the filling station in a transport cask, conveyed to the storage building and stored there. The storage building protects the gas cylinders against external impacts. The storage cells constitute a second barrier against the release of Kr-85. The heat produced during decay of the Kr-85 in the gas cylinders is carried off by natural convection of the air circulating in the storage cells. To study possible corrosion attack on special steels due to rubidium, experiments were conducted at 200 0 C during test periods up to 3500h. In order to compare properties at elevated temperatures, corrosion experiments were conducted at 500 0 C, which is far above the maximum licensed storage temperature of 200 0 C. Experiments were conducted concerning the adsorption of krypton on various adsorbents, thus reducing the pressure inside the gas cylinder during storage. A cost estimate based on 1980 prices

Effect of High Porosity Screen on the Near Wake of a Circular Cylinder

Directory of Open Access Journals (Sweden)

Sahin B.

2013-04-01

Full Text Available The change in flow characteristics downstream of a circular cylinder (inner cylinder surrounded by a permeable cylinder (outer cylinder made of a high porosity screen was investigated in shallow water using Particle Image Velocimetry (PIV technique. The diameter of the inner cylinder, outer cylinder and the water height were kept constant during the experiments as d = 50 mm, D = 100 mm and hw = 50 mm, respectively. The depth-averaged free stream velocity was also kept constant as U = 180 mm/s which corresponded to a Reynolds number of Red = 9000 based on the inner cylinder diameter. It was shown that the outer permeable cylinder had a substantialeffect on the vortex formation and consequent vortex shedding downstream of the circular cylinder, especially in the near wake. The time averaged vorticity layers, streamlines and velocity vector field depict that the location of the interaction of vortices considerably changed by the presence of the outer cylinder. Turbulent statistics clearly demonstrated that in comparison to the natural cylinder, turbulent kinetic energy and Reynolds stresses decreased remarkably downstream of the inner cylinder. Moreover, spectra of streamwise velocity fluctuations showed that the vortex shedding frequency significantly reduced compared to the natural cylinder case.

External Hand Forces Exerted by Long-Term Care Staff to Push Floor-Based Lifts: Effects of Flooring System and Resident Weight.

Science.gov (United States)

Lachance, Chantelle C; Korall, Alexandra M B; Russell, Colin M; Feldman, Fabio; Robinovitch, Stephen N; Mackey, Dawn C

2016-09-01

The aim of this study was to investigate the effects of flooring type and resident weight on external hand forces required to push floor-based lifts in long-term care (LTC). Novel compliant flooring is designed to reduce fall-related injuries among LTC residents but may increase forces required for staff to perform pushing tasks. A motorized lift may offset the effect of flooring on push forces. Fourteen female LTC staff performed straight-line pushes with two floor-based lifts (conventional, motor driven) loaded with passengers of average and 90th-percentile resident weights over four flooring systems (concrete+vinyl, compliant+vinyl, concrete+carpet, compliant+carpet). Initial and sustained push forces were measured by a handlebar-mounted triaxial load cell and compared to participant-specific tolerance limits. Participants rated pushing difficulty. Novel compliant flooring increased initial and sustained push forces and subjective ratings compared to concrete flooring. Compared to the conventional lift, the motor-driven lift substantially reduced initial and sustained push forces and perceived difficulty of pushing for all four floors and both resident weights. Participants exerted forces above published tolerance limits only when using the conventional lift on the carpet conditions (concrete+carpet, compliant+carpet). With the motor-driven lift only, resident weight did not affect push forces. Novel compliant flooring increased linear push forces generated by LTC staff using floor-based lifts, but forces did not exceed tolerance limits when pushing over compliant+vinyl. The motor-driven lift substantially reduced push forces compared to the conventional lift. Results may help to address risk of work-related musculoskeletal injury, especially in locations with novel compliant flooring. © 2016, Human Factors and Ergonomics Society.

76 FR 76435 - Multilayered Wood Flooring From China

Science.gov (United States)

2011-12-07

...)] Multilayered Wood Flooring From China Determinations On the basis of the record \\1\\ developed in the subject... multilayered wood flooring, provided for in subheadings 4409.10, 4409.29, 4412.31, 4412.32, 4412.39, 4412.94... flooring. The following companies are members of the CAHP: Anderson Hardwood Floors, LLC, Fountain Inn, SC...

49 CFR 180.205 - General requirements for requalification of specification cylinders.

Science.gov (United States)

2010-10-01

... each cylinder tested, except that for an analog device, interpolation to 1/2 of the marked gauge... for training persons who requalify cylinders using the volumetric expansion test method. (h) Cylinder...

MEMBRANE ACTION IN PROFILED STEEL SHEETING DRY BOARD (PSSDB FLOOR SLAB SYSTEM

Directory of Open Access Journals (Sweden)

MAHMOOD SERAJI

2013-02-01

Full Text Available Profiled steel sheeting dry board (PSSDB system is a lightweight composite structural system that made of the profiled steel sheeting (PSS connected to the dry board (DB by self-drilling and self-tapping screws. The objective of this paper is to study the effect of membrane action in improving the flexural capacities of the PSSDB system. According to the literatures, common failure of the PSSDB floor is due to local buckling in the top flanges of steel sheeting at the centre of a simply supported slab. Restraining the horizontal movement at supports may develop the membrane action (MA in the slab that can remarkably enhance the flexural rigidities of the floor. Experimental tests were conducted along with developing nonlinear finite element model to explore the effect of MA in the PSSDB floor. Experimental results of the PSSDB panel with simply end support were exploited to verify the nonlinear finite element results. The developed finite element model was then modified by restraining the horizontal movement of the slab at the supports. The obtained results disclosed that the developed compressive membrane action enhanced the stiffness of the slab at serviceability load by about 240%.

Plane Wall Effect of Flow around Two Circular Cylinders in Tandem Arrangement

Directory of Open Access Journals (Sweden)

Triyogi Yuwono,

2011-02-01

Full Text Available The flow characteristic around two circular cylinders in tandem arrangement located near a plane wall were investigated experimentally in a uniform flow at a Reynolds Number of 5.3 x 104. The center to center spacing between the two cylinders relative to the cylinder diameter was constantly maintained at P/D = 1.5. The pressure distributions along the surface of the cylinder and the plane wall were measured by varying the gap-to-diameter of cylinder ratio (G/D in the range of 0 < G/D < 0.467. Surface oil-film techniques were used to investigate the flow patterns on the cylinder. The result showed that for upstream cylinder, in the gap-to-diameter ratio G/D < /D, there is no stagnation point at front side of the upstream cylinder; it is gradually raised as the gap increase. For the downstream cylinder, a peak on the lower side of the front side of the cylinder is apparent in each of the pressure distributions. This peak represents the reattachment of shear layer that separates from lower side of the upstream cylinder. The reattachment point tends to move forward close to the angular position of  = 0o as the gap ratio increase. The shear layer bifurcates into two shear layers. One shear layer continues in the downstream direction, and the other shear layer flows in the upstream direction.

UF6 Cylinder Imaging by Fast Neutron Transmission Tomography

International Nuclear Information System (INIS)

McElroy, R.; Hausladen, P.; Blackston, M.; Croft, S.

2015-01-01

The common use Non-Destructive Assay techniques for the determination of 235 U enrichment and mass of UF6 cylinders used in the production of nuclear reactor fuel require prior knowledge of the physical distribution of the UF6 within the cylinder. The measurement performance for these techniques is typically evaluated based on assumed bounding case distributions of the material. However, little direct data such as radiographic or tomographic images, regarding the distribution of the UF6 within the cylinder is available against which to judge these assumptions. We have developed and tested a prototype active neutron tomographic imaging system employing an Associated Particle Imaging (API) neutron generator and an array of pixelated neutron scintillation counters. This system has been successfully used to obtain the 3-dimensional map of the distribution of UF6 within a type 12B storage cylinder. Results from these measurements are presented and the potential performance and utility of this technique with larger 30B and 48Y cylinders is discussed. (author)

Experimental study on flow past a rotationally oscillating cylinder

Science.gov (United States)

Gao, Yang-yang; Yin, Chang-shan; Yang, Kang; Zhao, Xi-zeng; Tan, Soon Keat

2017-08-01

A series of experiments was carried out to study the flow behaviour behind a rotationally oscillating cylinder at a low Reynolds number (Re=300) placed in a recirculation water channel. A stepper motor was used to rotate the cylinder clockwise- and- counterclockwise about its longitudinal axis at selected frequencies. The particle image velocimetry (PIV) technique was used to capture the flow field behind a rotationally oscillating cylinder. Instantaneous and timeaveraged flow fields such as the vorticity contours, streamline topologies and velocity distributions were analyzed. The effects of four rotation angle and frequency ratios F r ( F r= f n/ f v, the ratio of the forcing frequency f n to the natural vortex shedding frequency f v) on the wake in the lee of a rotationally oscillating cylinder were also examined. The significant wake modification was observed when the cylinder undergoes clockwise-and-counterclockwise motion with amplitude of π, especially in the range of 0.6≤ F r≤1.0.

Adaptive individual-cylinder thermal state control using intake air heating for a GDCI engine

Science.gov (United States)

Roth, Gregory T.; Sellnau, Mark C.

2016-08-09

A system for a multi-cylinder compression ignition engine includes a plurality of heaters, at least one heater per cylinder, with each heater configured to heat air introduced into a cylinder. Independent control of the heaters is provided on a cylinder-by-cylinder basis. A combustion parameter is determined for combustion in each cylinder of the engine, and control of the heater for that cylinder is based on the value of the combustion parameter for combustion in that cylinder. A method for influencing combustion in a multi-cylinder compression ignition engine, including determining a combustion parameter for combustion taking place in a cylinder of the engine and controlling a heater configured to heat air introduced into that cylinder, is also provided.

Cracked lifting lug welds on ten-ton UF{sub 6} cylinders

Energy Technology Data Exchange (ETDEWEB)

Dorning, R.E. [Martin Marietta Energy Systems, Inc., Piketon, OH (United States)

1991-12-31

Ten-ton, Type 48X, UF{sub 6} cylinders are used at the Portsmouth Gaseous Diffusion Plant to withdraw enriched uranium hexafluoride from the cascade, transfer enriched uranium hexafluoride to customer cylinders, and feed enriched product to the cascade. To accomplish these activities, the cylinders are lifted by cranes and straddle carriers which engage the cylinder lifting lugs. In August of 1988, weld cracks on two lifting lugs were discovered during preparation to lift a cylinder. The cylinder was rejected and tagged out, and an investigating committee formed to determine the cause of cracking and recommend remedial actions. Further investigation revealed the problem may be general to this class of cylinder in this use cycle. This paper discusses the actions taken at the Portsmouth site to deal with the cracked lifting lug weld problem. The actions include inspection activities, interim corrective actions, metallurgical evaluation of cracked welds, weld repairs, and current monitoring/inspection program.

Guided Circumferential Waves in Layered Poroelastic Cylinders

Directory of Open Access Journals (Sweden)

Shah S.A.

2016-12-01

Full Text Available The present paper investigates the propagation of time harmonic circumferential waves in a two-dimensional hollow poroelastic cylinder with an inner shaft (shaft-bearing assembly. The hollow poroelastic cylinder and inner shaft are assumed to be infinite in axial direction. The outer surface of the cylinder is stress free and at the interface, between the inner shaft and the outer cylinder, it is assumed to be free sliding and the interfacial shear stresses are zero, also the normal stress and radial displacements are continuous. The frequency equation of guided circumferential waves for a permeable and an impermeable surface is obtained. When the angular wave number vanish the frequency equation of guided circumferential waves for a permeable and an impermeable surface degenerates and the dilatational and shear waves are uncoupled. Shear waves are independent of the nature of surface. The frequency equation of a permeable and an impermeable surface for bore-piston assembly is obtained as a particular case of the model under consideration when the outer radius of the hollow poroelastic cylinder tends to infinity. Results of previous studies are obtained as a particular case of the present study. Nondimensional frequency as a function of wave number is presented graphically for two types of models and discussed. Numerical results show that, in general, the first modes are linear for permeable and impermeable surfaces and the frequency of a permeable surface is more than that of an impermeable surface.

Processing mixed-waste compressed-gas cylinders at the Oak Ridge Reservation

International Nuclear Information System (INIS)

Morris, M.I.; Conley, T.B.; Osborne-Lee, I.W.

1998-05-01

Until recently, several thousand kilograms of compressed gases were stored at the Oak Ridge Reservation (ORR), in Oak Ridge, Tennessee, because these cylinders could not be taken off-site in their state of configuration for disposal. Restrictions on the storage of old compressed-gas cylinders compelled the Waste Management Organization of Lockheed Martin Energy Systems, Inc. (LMES) to dispose of these materials. Furthermore, a milestone in the ORR Site Treatment Plan required repackaging and shipment off-site of 21 cylinders by September 30, 1997. A pilot project, coordinated by the Chemical Technology Division (CTD) at the Oak Ridge National Laboratory (ORNL), was undertaken to evaluate and recontainerize or neutralize these cylinders, which are mixed waste, to meet that milestone. Because the radiological component was considered to be confined to the exterior of the cylinder, the contents (once removed from the cylinder) could be handled as hazardous waste, and the cylinder could be handled as low-level waste (LLW). This pilot project to process 21 cylinders was important because of its potential impact. The successful completion of the project provides a newly demonstrated technology which can now be used to process the thousands of additional cylinders in inventory across the DOE complex. In this paper, many of the various aspects of implementing this project, including hurdles encountered and the lessons learned in overcoming them, are reported

Radiant Floor Cooling Systems

DEFF Research Database (Denmark)

Olesen, Bjarne W.

2008-01-01

In many countries, hydronic radiant floor systems are widely used for heating all types of buildings such as residential, churches, gymnasiums, hospitals, hangars, storage buildings, industrial buildings, and smaller offices. However, few systems are used for cooling.This article describes a floor...... cooling system that includes such considerations as thermal comfort of the occupants, which design parameters will influence the cooling capacity and how the system should be controlled. Examples of applications are presented....

Convective heat transfer from a heated elliptic cylinder at uniform wall temperature

Energy Technology Data Exchange (ETDEWEB)

Kaprawi, S.; Santoso, Dyos [Mechanical Department of Sriwijaya University, Jl. Raya Palembang-Prabumulih Km. 32 Inderalaya 50062 Ogan Ilir (Indonesia)

2013-07-01

This study is carried out to analyse the convective heat transfer from a circular and an elliptic cylinders to air. Both circular and elliptic cylinders have the same cross section. The aspect ratio of cylinders range 0-1 are studied. The implicit scheme of the finite difference is applied to obtain the discretized equations of hydrodynamic and thermal problem. The Choleski method is used to solve the discretized hydrodynamic equation and the iteration method is applied to solve the discretized thermal equation. The circular cylinder has the aspect ratio equal to unity while the elliptical cylinder has the aspect ratio less than unity by reducing the minor axis and increasing the major axis to obtain the same cross section as circular cylinder. The results of the calculations show that the skin friction change significantly, but in contrast with the elliptical cylinders have greater convection heat transfer than that of circular cylinder. Some results of calculations are compared to the analytical solutions given by the previous authors.

Magnetic resonance imaging of pelvic floor dysfunction.

Science.gov (United States)

Lalwani, Neeraj; Moshiri, Mariam; Lee, Jean H; Bhargava, Puneet; Dighe, Manjiri K

2013-11-01

Pelvic floor dysfunction is largely a complex problem of multiparous and postmenopausal women and is associated with pelvic floor or organ descent. Physical examination can underestimate the extent of the dysfunction and misdiagnose the disorders. Functional magnetic resonance (MR) imaging is emerging as a promising tool to evaluate the dynamics of the pelvic floor and use for surgical triage and operative planning. This article reviews the anatomy and pathology of pelvic floor dysfunction, typical imaging findings, and the current role of functional MR imaging. Copyright © 2013 Elsevier Inc. All rights reserved.

Cylinder gauge measurement using a position sensitive detector

International Nuclear Information System (INIS)

St John, W. Doyle

2007-01-01

A position sensitive detector (PSD) has been used to determine the diameter of cylindrical pins based on the shift in a laser beam's centroid. The centroid of the light beam is defined here as the weighted average of position by the local intensity. A shift can be observed in the centroid of an otherwise axially symmetric light beam, which is partially obstructed. Additionally, the maximum shift in the centroid is a unique function of the obstructing cylinder diameter. Thus to determine the cylinder diameter, one only needs to detect this maximum shift as the cylinder is swept across the beam

[Continuous improvement of portable domestic pelvic floor neuromuscular electrical stimulation on the pelvic floor function of patients with urinary incontinence].

Science.gov (United States)

Sun, Zhijing; Zhu, Lan; Lang, Jinghe; Wang, Wei; Shi, Honghui; Pang, Hongxia; Shi, Xinwen

2015-12-01

To evaluate continuous improvement of portable domestic pelvic floor neuromuscular electrical stimulation on the pelvic floor function of patients with stress urinary incontinence after short-term pelvic floor electrophysiological treatment in hospital. Totally 60 women with stress urinary incontinence were recruited for this randomized controlled trial. The control group including a total of 30 patients, only received 4 weeks pelvic floor electrophysiological treatment in the hospital. Family consolidation treatment group (experimental group) including 30 patients, after 4-week treatment in hospital, received 12-week of pelvic floor neuromuscular electrical stimulation using portable electrical stimulator at home under the guidance of doctors. In post-treatment 6 months and 9 months, 1-hour pad test was measured for urine leakage, pelvic floor electrical physiological parameters were assessed, and subjective improvement of symptoms of urinary incontinence were evaluated. All these data were analysed to compare the effect of the two groups. In 9 months after treatment, average change of urine leakage, the control group and experiment group were (75±24)% versus (99±3)%, the difference was statistically significant (Pcontinuous improvement of pelvic floor function.

Conceptual & Engineering Design of Plug-in Cryostat Cylinder for Super-Conducting Central Solenoid of SST-1

Science.gov (United States)

Biswas, Prabal; Santra, Prosenjit; Vasava, Kirit; Jayswal, Snehal; Parekh, Tejas; Chauhan, Pradeep; Patel, Hitesh; Pradhan, Subrata

2017-04-01

SST-1, country’s first indigenously built steady state super-conducting tokamak is planned to be equipped with an Nb3Sn based superconducting central solenoid, which will replace the existing copper conductor TR1 coil for the purpose of Ohmic breakdown. This central solenoid (CS) of four layers with each layer having 144 turns with an OD of 573 mm, ID of 423 mm length of 2483 mm will be housed inside a high vacuum, CRYO compatible plug-in cryostat thin shell having formed from SS 304L plate duly rolled and welded to form cylinder along with necessary accessories like LN2 bubble panel, current lead chamber, coil and cylinder support structure etc. This paper will present the design drivers, material selection, advantages and constraints of the plug-in cryostat concept, sub-systems of plug-in cryostat, its conceptual and engineering design, CAD models, finite element analysis using ANSYS, safety issues and diagnostics, on-going works about fabrication, quality assurance/control and assembly/integration aspects with in the existing SST-1 machine bore.

Experimental and finite element prediction of bursting pressure in compound cylinders

International Nuclear Information System (INIS)

Majzoobi, G.H.; Farrahi, G.H.; Pipelzadeh, M.K.; Akbari, A.

2004-01-01

Aluminium cylinders with a constant ratio of outer to inner radii, k=2.2, with different diametral interferences and various shrinkage radii were subjected to bursting and autofrettage pressures. Numerical simulations of the compound cylinders were also performed using the finite element code, NISA. The results can predict the optimum shrinkage radius to a reasonable accuracy with the use of finite element analysis. This radius corresponds to the situation when the maximum von-Mises stress at the internal radii of both the inner and outer cylinders become equal. It was shown that the maximum von-Mises stress across the wall of the cylinder is at the minimum at this shrinkage radius. The optimum diametral interference was found to be that which sufficiently brought the contact surface of the inner and outer cylinders to the point of yielding. Should the shrinkage pressure exceed the elastic limit, the pressure capacity of the cylinder will not be improved. The numerical and experimental results show that autofrettage had no effect on the bursting pressure of the thick-walled compound cylinder for the material tested

Test and Analysis Correlation of a Large-Scale, Orthogrid-Stiffened Metallic Cylinder without Weld Lands

Science.gov (United States)

Rudd, Michelle T.; Hilburger, Mark W.; Lovejoy, Andrew E.; Lindell, Michael C.; Gardner, Nathaniel W.; Schultz, Marc R.

2018-01-01

The NASA Engineering Safety Center (NESC) Shell Buckling Knockdown Factor Project (SBKF) was established in 2007 by the NESC with the primary objective to develop analysis-based buckling design factors and guidelines for metallic and composite launch-vehicle structures.1 A secondary objective of the project is to advance technologies that have the potential to increase the structural efficiency of launch-vehicles. The SBKF Project has determined that weld-land stiffness discontinuities can significantly reduce the buckling load of a cylinder. In addition, the welding process can introduce localized geometric imperfections that can further exacerbate the inherent buckling imperfection sensitivity of the cylinder. Therefore, single-piece barrel fabrication technologies can improve structural efficiency by eliminating these weld-land issues. As part of this effort, SBKF partnered with the Advanced Materials and Processing Branch (AMPB) at NASA Langley Research Center (LaRC), the Mechanical and Fabrication Branch at NASA Marshall Space Flight Center (MSFC), and ATI Forged Products to design and fabricate an 8-ft-diameter orthogrid-stiffened seamless metallic cylinder. The cylinder was subjected to seven subcritical load sequences (load levels that are not intended to induce test article buckling or material failure) and one load sequence to failure. The purpose of this test effort was to demonstrate the potential benefits of building cylindrical structures with no weld lands using the flow-formed manufacturing process. This seamless barrel is the ninth 8-ft-diameter metallic barrel and the first single-piece metallic structure to be tested under this program.

An evaluation of Microleakage of Posterior Composites

Directory of Open Access Journals (Sweden)

Mohammadi N

1999-12-01

Full Text Available Polymerization contraction may produce defects in the composite - tooth bond. This may lead to bond failure and microleakage. The aim of this study was to reduce microleakage of posterior composites using different methods. 45 molar and premolars extracted teeth were choosen. The cavities were randomly assigned into 5 groups of 9. Box-shaped cavities were prepared on each side of proximal surfaces and restored by five different methods. Group 1 was filled by a light-cured composite and dentin bonding agents (DBAs with light curing from the occlusal area. Group 2 was filled by a light-cured {LC} composite and DBA, in addition the angle between the light source and occlusal area was 45 degree. After conditioning of teeth in-group 3, LC glass ionomer was placed on the gingival floor and then filled by a light-cured composite and DBA. In group 4, after conditioning, the teeth were lined by a LC glass ionomer and then self-cured composite was placed on gingival floor. This group was filled with LC composite. In Group 5 DBA was used followed by placing a self-curing composite on gingival floor and filled by LC composite. The teeth were subjected to 500 thermocycling (5°C and 55°C with dowel time 30 s and stored in 0.5% basic fushin for 24 hours. Dye penetration was evaluated by light microscope. The results were tested by Kruskat-Wallis one-way analysis of variance by rank. The comparison between treatment groups showed highly significant difference {P<0.0001. No significant difference was found between groups 3 versus 4 and groups 1,2,5 versus 3,4. Group 3 showed the least microleakage score. Therefore least microleakage was obtained by the group which used L C glass ionomer and DBA followed by filling a composite.

PIV Measurements of He II Counterflow Around a Cylinder

International Nuclear Information System (INIS)

Fuzier, S.; Van Stiver, S. W.; Zhang, T.

2006-01-01

The induced flow field of counterflow He II across a circular cylinder has been quantitatively studied using the particle image velocimetry (PIV) technique. Two different size cylinders (6.35 mm and 2 mm in diameter) were used and placed in a 20 mm wide rectangular channel. In these experiments, large-scale eddy motion generated by the He II counterflow was observed both in front of and behind the cylinder, an effect which has no analogue in classical fluids

Preliminary Concept of Operations for a Global Cylinder Identification and Monitoring System

Energy Technology Data Exchange (ETDEWEB)

Whitaker, J. M. [ORNL; White-Horton, J. L. [ORNL; Morgan, J. B. [InSolves Associates

2013-08-01

This report describes a preliminary concept of operations for a Global Cylinder Identification and Monitoring System that could improve the efficiency of the International Atomic Energy Agency (IAEA) in conducting its current inspection activities and could provide a capability to substantially increase its ability to detect credible diversion scenarios and undeclared production pathways involving UF6 cylinders. There exist concerns that a proliferant State with access to enrichment technology could obtain a cylinder containing natural or low-enriched uranium hexafluoride (UF6) and produce a significant quantity (SQ)1 of highly enriched uranium in as little as 30 days. The National Nuclear Security Administration (NNSA) through the Next Generation Safeguards Initiative sponsored a multi-laboratory team to develop an integrated system that provides for detecting scenarios involving 1) diverting an entire declared cylinder for enrichment at a clandestine facility, 2) misusing a declared cylinder at a safeguarded facility, and 3) using an undeclared cylinder at a safeguarded facility. An important objective in developing this integrated system was to improve the timeliness for detecting the cylinder diversion and undeclared production scenarios. Developing this preliminary concept required in-depth analyses of current operational and safeguards practices at conversion, enrichment, and fuel fabrication facilities. The analyses evaluated the processing, movement, and storage of cylinders at the facilities; the movement of cylinders between facilities (including cylinder fabrication); and the misuse of safeguarded facilities.

Emplacement and retrieval equipment design considerations for a repository in salt

International Nuclear Information System (INIS)

Nair, B.R.; Bahorich, R.J.

1987-01-01

The current design concept for the disposal of nuclear high level waste packages in a repository in salt is based on the emplacement of individual packages in vertical boreholes in the underground mine floor. A key requirement is that the waste packages be capable of being retrieved during the last 26 years of the 76-year repository operating period. The unique design considerations relating to the retrieval of waste packages emplaced in bedded salt are presented in this paper. The information is based on the experience developed during the design of vertical emplacement and retrieval equipment in support of the Sandia Defense High Level Waste experiments at the Waste Isolation Pilot Plant. Also included are the impact of retrievability on the design of the equipment, the special salt cutting technology that was developed for this application, and a description of the equipment

Kinematic and Dynamic Simulation Analysis of Hydraulic Excavator’s Working Equipment based on ADAMS

Directory of Open Access Journals (Sweden)

Yu Hong Yan

2016-01-01

Full Text Available This paper establishes the 3D excavator model according to the actual size in UG firstly. Then based on the virtual simulation software ADAMS, the virtual prototype of the working device is built by adding interrelated constraints(kinematic pair and hydraulic cylinder driving function and load secondly. This paper gets the main parameters of the excavator working scope and the pressure situation change curves of point of each hydraulic cylinder by making kinematic and dynamic simulation analysis of hydraulic excavator’s working equipment at last. The conclusion providing design theory and improvement for the excavator’s working device, which also play an important role in improving the level of China’s excavator design, enhancing excavator’s performance and promoting the rapid development of excavator industry.

Knowledge of the pelvic floor in nulliparous women

OpenAIRE

Neels, Hedwig; Wyndaele, Jean-Jacques; Tjalma, Wiebren A. A.; De Wachter, Stefan; Wyndaele, Michel; Vermandel, Alexandra

2016-01-01

[Purpose] Proper pelvic floor function is important to avoid serious dysfunctions including incontinence, prolapse, and sexual problems. The current study evaluated the knowledge of young nulliparous women about their pelvic floor and identified what additional information they wanted. [Subjects and Methods] In this cross-sectional survey, a validated, 36 item questionnaire was distributed to 212 nulliparous women. The questionnaire addressed demography, pelvic floor muscles, pelvic floor dys...

Bursting pressure of autofrettaged cylinders with inclined external cracks

International Nuclear Information System (INIS)

Seifi, Rahman; Babalhavaeji, Majid

2012-01-01

Autofrettaging a pressure vessel improves its pressure capacity. This is reliable if there isn’t any crack or other type of flaws. In this paper, the effects of external surface cracks on bursting pressure of autofrettaged cylinders are studied. It is observed that bursting pressure decreases considerably (up to 30%) due to external cracks in the cylinders without autofrettage. This reduction increases for high levels of the applied autofrettage. External axial cracks have more effects than inclined cracks. Comparing experimental and numerical results show that the numerical methods can acceptably predict the bursting pressure of the autofrettaged cracked cylinders. These predictions are valid when the fracture parameter (J-Integral) is calculated from the modified equation that takes into account the effects of residual stresses. - Highlights: ► Modified J-Integral can be used for study of autofrettaged cracked cylinders. ► External axial cracks reduce considerably the pressure capacity of cylinders. ► External circumferential cracks have not considerable effects on bursting pressure. ► Autofrettage has contrary effects on external crack in compared with internal crack.

The study of fix composite panel and steel plates on testing stand

Science.gov (United States)

Wróbel, A.; Płaczek, M.; Wachna, M.

2016-08-01

In this paper the practical possibilities of strength verification analysis of composite materials used in the manufacture of selected components of railway wagons are presented. Real laboratory stand for measurements in a scale controlled by PLC controller were made. The study of different types of connections of composite materials with sheet metal is presented. In one of the chapter of this paper principles construction of testing stand with pneumatic cylinder were presented. Mainly checking of displacements and stresses generated on the sheet as a result of pneumatic actuators load for composite boards was carried out. The use of the controller with operating panel allows to easy programming testing cycle. The user can define the force generated by the actuator by change of air pressure in cylinder. Additionally the location of acting cylinders and their jump can be changed by operator. The examination of the volume displacements was done by displacement sensor, and the tensile strain gauge. All parameters are written in CatmanEasy - data acquisition software. This article presents the study of stresses and displacements in the composite plates joined with sheet metal, in summary of this article, the authors compare the obtained results with the computer simulation results in the article: "Simulation of stresses in an innovative combination of composite with sheet".

Container floor at high temperatures

International Nuclear Information System (INIS)

Reutler, H.; Klapperich, H.J.; Mueller-Frank, U.

1978-01-01

The invention describes a floor for container which is stressed at high, changing temperatures and is intended for use in gas-cooled nuclear reactors. Due to the downward cooling gas flow in these types of reactor, the reactor floor is subjected to considerable dimensional changes during switching on and off. In the heating stage, the whole graphite structure of the reactor core and floor expands. In order to avoid arising constraining forces, sufficiently large expansion spaces must be allowed for furthermore restoring forces must be present to close the gaps again in the cooling phase. These restoring forces must be permanently present to prevent loosening of the core cuits amongst one another and thus uncontrollable relative movement. Spring elements are not suitable due to fast fatigue as a result of high temperatures and radiation exposure. It is suggested to have the floor elements supported on rollers whose rolling planes are downwards inclined to a fixed point for support. The construction is described in detail by means of drawings. (GL) [de

A numerical simulation of VIV on a flexible circular cylinder

International Nuclear Information System (INIS)

Xie Fangfang; Deng Jian; Zheng Yao; Xiao Qing

2012-01-01

In this paper, numerical simulations of a flexible circular cylinder subjected to a vortex-induced vibration (VIV) are conducted. The Reynolds number for simulations is fixed at 1000. The finite volume method is applied for modeling fluid flow with the moving meshes feature. The dynamic response of a flexible cylinder fixed at both ends is modeled by the Euler–Bernoulli beam theory. The comparison between two-dimensional (2D) simulations and 3D simulations for the flexible cylinder shows that the maximum response amplitude of the cross-flow oscillation is about 0.57D for 2D rigid cylinders (modeled by a spring–damper–mass model) and 1.03D for flexible cylinders, respectively. The results from 3D simulations are closer to previous experimental results. Furthermore, the results obtained with various frequency ratios show that different wake patterns exist according to the frequency ratio, such as 2S mode, 2P mode and some more complicated modes. The wake pattern is different at various sections along the cylinder length, due to the fact that the two ends of the beam are fixed. The vibration of the flexible cylinder can also greatly alter the three dimensionality in the wake, which is our research in future work, especially in the transition region for Reynolds number ranging from 170 to 300. (paper)

No bulging of floor heating pipes to be expected in case of incomplete floor plastering

Energy Technology Data Exchange (ETDEWEB)

Radtke, U

1983-02-01

According to advertising slogans floor heating pipes are said to be damaged prematurely by bulges if they are not completely surrounded by flooring plaster. The author has thoroughly dealt with this problem and made the respective measurements. He found out that there are so few bulges occurring that they cannot lead to damages.

Evaluation of the composition of filters additional of equipment radiological intraoral by energy dispersive x-ray fluorescence (EDXRF)

International Nuclear Information System (INIS)

Franca, Alana Caroline; Torres, Catarina A.M.P.; Rocha, Ana S.S.; Deniak, Valeriy; Lara, Alessandro L.; Paschuk, Sergei A.; Fernandes, Angela; Westphalen, Fernando Henrique

2013-01-01

The need for high quality standards for radiographic images in order to make a diagnosis assertive, and being the additional filtration required in the intraoral X-ray equipment show the need of evaluating these filters. This study aims to examine the influence of the elemental composition of the filters of X-ray of dental intraoral equipment in the radiographic images quality. The filters analysis were performed by using the energy dispersive X-ray fluorescence method (EDXRF). Ten conventional filters were analysed. In this study, 33 radiographic exposures were performed using films: twenty radiographs in the incisor region and ten in the molar region, three exposures were also made in the same regions with same conditions without using filter. After radiographs development, optical density was measure and all radiographs were submitted to subjective evaluation by dental radiologists. Data obtained were correlated to effects evaluation of the elemental composition of all filters in the quality of the radiographic images. The elements found were: aluminum, cobalt, copper, sulfur, iron, manganese, titanium, zinc, and zirconium. The images obtained were identified in groups: Molars to 0.3 s; Incisors to 0.2 s; Incisors to 0.3 s, and for the group without filters. From the results obtained it was concluded that both unclear radiographs and ideal radiographs were produced by using filters of elementary common. Therefore, conventional filters evaluated were an acceptable option to produce quality images in dental radiology, despite differences in the composition of the alloys. (author)

Evaluation of the composition of filters additional of equipment radiological intraoral by energy dispersive x-ray fluorescence (EDXRF)

Energy Technology Data Exchange (ETDEWEB)

Franca, Alana Caroline; Torres, Catarina A.M.P.; Rocha, Ana S.S.; Deniak, Valeriy; Lara, Alessandro L.; Paschuk, Sergei A., E-mail: alanacarolinef@gmail.com, E-mail: sergei@utfpr.edu.br [Universidade Tecnologica Federal do Parana (CPGEI/UTFPR), Curitiba, PR (Brazil). Programa de Pos-Graduacao em Engenharia Eletrica e Informatica Industrial; Fernandes, Angela; Westphalen, Fernando Henrique, E-mail: angelafernandes@ufpr.br [Universidade Federal do Parana (UFPR), Curitiba, PR (Brazil). Setor de Ciencias da Saude

2013-07-01

The need for high quality standards for radiographic images in order to make a diagnosis assertive, and being the additional filtration required in the intraoral X-ray equipment show the need of evaluating these filters. This study aims to examine the influence of the elemental composition of the filters of X-ray of dental intraoral equipment in the radiographic images quality. The filters analysis were performed by using the energy dispersive X-ray fluorescence method (EDXRF). Ten conventional filters were analysed. In this study, 33 radiographic exposures were performed using films: twenty radiographs in the incisor region and ten in the molar region, three exposures were also made in the same regions with same conditions without using filter. After radiographs development, optical density was measure and all radiographs were submitted to subjective evaluation by dental radiologists. Data obtained were correlated to effects evaluation of the elemental composition of all filters in the quality of the radiographic images. The elements found were: aluminum, cobalt, copper, sulfur, iron, manganese, titanium, zinc, and zirconium. The images obtained were identified in groups: Molars to 0.3 s; Incisors to 0.2 s; Incisors to 0.3 s, and for the group without filters. From the results obtained it was concluded that both unclear radiographs and ideal radiographs were produced by using filters of elementary common. Therefore, conventional filters evaluated were an acceptable option to produce quality images in dental radiology, despite differences in the composition of the alloys. (author)

Surface flaw in a thermally shocked hollow cylinder

International Nuclear Information System (INIS)

Kobayashi, A.S.; Emery, A.F.; Polvanich, N.; Love, W.J.

1975-01-01

The objective of this paper is to illustrate a procedure for estimating the stress intensity factors of a semi-elliptical crack located in the inner or outer surface of a thermally shocked hollow cylinder. The first step in this procedure is to estimate the transient thermal elastic stresses induced by sudden cooling of an uncracked cylinder by numerically evaluating standard heat transfer and thermal stress formulae. The stresses at the location of the crack surface in the uncracked cylinder are eliminated by the method of superposition in order to obtain a stress free crack surface. The stress intensity factors are then determined by a judicious use of two sets of solutions, one set involving stress intensity factors for a semi-elliptical crack in a flat plate and subjected to a polynomial distribution of pressure loading, and another set involving single-edge notched plates with prescribed edge-displacements and single-edge internally or externally notched cylinders with thermal shock loading. The former solutions are determined by the alternating technique in three-dimensional fracture mechanics with a fourth order polynomial pressure distribution on the crack surface where both the front and back surface effects are accounted for. The latter solutions involve two-dimensional finite element solutions of single-edge notched plates with prescribed edge-displacements and single-edge notched cylinders with thermal shock loading. By comparing these two two-dimensional solutions, an estimate of the effect of the cylindrical curvature on an edge-cracked plate is obtained. The combination of these two sets of solutions thus yields an estimate of the stress intensity factor in an internal and external semi-elliptical crack in a thermally shocked cylinder

Response of Buried Vertically Oriented Cylinders to Dynamic Loading,

Science.gov (United States)

1980-06-01

BALSARA • , . / ,, _,-, -. 1i S ,LESPONSE OF BURIED VERTICALLY 9RIENTED CYLINDERS 𔃺 .-TO DINAMIC LOADING_ 9AYLE E. LRTOrwW&-N JIIMY P./BALSARA Nk...1.7, 2,8, and 4.0 inches). The end caps for the cylinders consisted of a steel shell filled with high- strength concrete; however, the end caps were...not designed to be test articles. The average concrete compressive strength of the cylinders on test day was 44.0 MPa (6,380 psi). The three DEOT

Recognition and Management of Nonrelaxing Pelvic Floor Dysfunction

OpenAIRE

Faubion, Stephanie S.; Shuster, Lynne T.; Bharucha, Adil E.

2012-01-01

Nonrelaxing pelvic floor dysfunction is not widely recognized. Unlike in pelvic floor disorders caused by relaxed muscles (eg, pelvic organ prolapse or urinary incontinence, both of which often are identified readily), women affected by nonrelaxing pelvic floor dysfunction may present with a broad range of nonspecific symptoms. These may include pain and problems with defecation, urination, and sexual function, which require relaxation and coordination of pelvic floor muscles and urinary and ...

Manufacturing of Nanocomposite Carbon Fibers and Composite Cylinders

Science.gov (United States)

Tan, Seng; Zhou, Jian-guo

2013-01-01

Pitch-based nanocomposite carbon fibers were prepared with various percentages of carbon nanofibers (CNFs), and the fibers were used for manufacturing composite structures. Experimental results show that these nanocomposite carbon fibers exhibit improved structural and electrical conductivity properties as compared to unreinforced carbon fibers. Composite panels fabricated from these nanocomposite carbon fibers and an epoxy system also show the same properties transformed from the fibers. Single-fiber testing per ASTM C1557 standard indicates that the nanocomposite carbon fiber has a tensile modulus of 110% higher, and a tensile strength 17.7% times higher, than the conventional carbon fiber manufactured from pitch. Also, the electrical resistance of the carbon fiber carbonized at 900 C was reduced from 4.8 to 2.2 ohm/cm. The manufacturing of the nanocomposite carbon fiber was based on an extrusion, non-solvent process. The precursor fibers were then carbonized and graphitized. The resultant fibers are continuous.

Floor-Fractured Craters through Machine Learning Methods

Science.gov (United States)

Thorey, C.

2015-12-01

Floor-fractured craters are impact craters that have undergone post impact deformations. They are characterized by shallow floors with a plate-like or convex appearance, wide floor moats, and radial, concentric, and polygonal floor-fractures. While the origin of these deformations has long been debated, it is now generally accepted that they are the result of the emplacement of shallow magmatic intrusions below their floor. These craters thus constitute an efficient tool to probe the importance of intrusive magmatism from the lunar surface. The most recent catalog of lunar-floor fractured craters references about 200 of them, mainly located around the lunar maria Herein, we will discuss the possibility of using machine learning algorithms to try to detect new floor-fractured craters on the Moon among the 60000 craters referenced in the most recent catalogs. In particular, we will use the gravity field provided by the Gravity Recovery and Interior Laboratory (GRAIL) mission, and the topographic dataset obtained from the Lunar Orbiter Laser Altimeter (LOLA) instrument to design a set of representative features for each crater. We will then discuss the possibility to design a binary supervised classifier, based on these features, to discriminate between the presence or absence of crater-centered intrusion below a specific crater. First predictions from different classifier in terms of their accuracy and uncertainty will be presented.

Fatigue resistance and stiffness of glass fiber-reinforced urethane dimethacrylate composite.

Science.gov (United States)

Narva, Katja K; Lassila, Lippo V J; Vallittu, Pekka K

2004-02-01

Retentive properties of cast metal clasps decrease over time because of metal fatigue. Novel fiber-reinforced composite materials are purported to have increased fatigue resistance compared with metals and may offer a solution to the problem of metal fatigue. The aim of this study was to investigate the fatigue resistance and stiffness of E-glass fiber-reinforced composite. Twelve cylindrical fiber-reinforced composite test cylinders (2 mm in diameter and 60 mm in length) were made from light-polymerized urethane dimethacrylate monomer with unidirectional, single-stranded, polymer preimpregnated E-glass fiber reinforcement. Six cylinders were stored in dry conditions and 6 in distilled water for 30 days before testing. Fatigue resistance was measured by a constant-deflection fatigue test with 1 mm of deflection across a specimen span of 11 mm for a maximum of 150,000 loading cycles. The resistance of the cylinder against deflection was measured (N) and the mean values of the force were compared by 1-way analysis of variance (alpha = .05). The flexural modulus (GPa) was calculated for the dry and water-stored cylinders for the first loading cycle. Scanning electron microscopy was used to assess the distribution of the fibers, and the volume percent of fibers and polymer were assessed by combustion analysis. The test cylinders did not fracture due to fatigue following 150,000 loading cycles. Flexural modulus at the first loading cycle was 18.9 (+/- 2.9) GPa and 17.5 (+/- 1.7) GPa for the dry and water-stored cylinders, respectively. The mean force required to cause the first 1-mm deflection was 33.5 (+/- 5.2) N and 37.7 (+/- 3.6) N for the dry and water stored cylinders, respectively; however, the differences were not significant. After 150,000 cycles the mean force to cause 1-mm deflection was significantly reduced to 23.4 (+/- 8.5) N and 13.1 (+/- 3.5) N, respectively (P fiber- and polymer-rich areas within the specimens and indicated that individual fibers were

Advanced engine management of individual cylinders for control of exhaust species

Science.gov (United States)

Graves, Ronald L [Knoxville, TN; West, Brian H [Knoxville, TN; Huff, Shean P [Knoxville, TN; Parks, II, James E

2008-12-30

A method and system controls engine-out exhaust species of a combustion engine having a plurality of cylinders. The method typically includes various combinations of steps such as controlling combustion parameters in individual cylinders, grouping the individual cylinders into a lean set and a rich set of one or more cylinders, combusting the lean set in a lean combustion parameter condition having a lean air:fuel equivalence ratio, combusting the rich set in a rich combustion parameter condition having a rich air:fuel equivalence ratio, and adjusting the lean set and the rich set of one or more cylinders to generate net-lean combustion. The exhaust species may have elevated concentrations of hydrogen and oxygen.

An experimental investigation of the efficacy of perforated holes on unsteady aerodynamic force reduction for a 2D cylinder in uniform incoming flow

Science.gov (United States)

Sudalaimuthu, Vignesh; Liu, Xiaofeng

2017-11-01

A series of wind tunnel aerodynamic force measurements have been conducted on a 2D hollow cylinder with perforated holes uniformly-distributed on its surface to evaluate the efficacy of perforation as a means of passive flow control in reducing unsteady aerodynamic forces. Both smooth and perforated cylinders were tested for comparison at Reynolds numbers ranging from 50,000 to 200,000 corresponding to free stream velocities varying from 5 to 20 m/s (at an increment of 5 m/s) and a cylinder diameter of 0.152 m. The aerodynamic forces acting on the testing model were measured using a 6-component load cell. For each tunnel speed, the test has been repeated for 10 runs at a sampling rate of 10 kHz for 60 seconds each, with a total of 6,000,000 samples acquired for each test. Both mean and r.m.s. values of the lift and drag coefficients were calculated. Power spectral density distributions of the unsteady aerodynamic force loading was analyzed to investigate the effect of the perforation on the frequency composition. Comparisons indicate that the perforated cylinder with a 8% porosity and a hole diameter of about 2% of that of the cylinder gives both substantially less unsteady drag and lift than those of the smooth cylinder for the entire Reynolds number range tested, with the r.m.s. force reduction from 8% to 82% for the drag and 64% to 85% for the lift, confirming a corresponding beneficial reduction in flow-induced cylinder vibration as observed during the experiments. Sponsor: San Diego State University.

Transient thermal stress problem for a circumferentially cracked hollow cylinder

Science.gov (United States)

Nied, H. F.; Erdogan, F.

1982-01-01

The transient thermal stress problem for a hollow elasticity cylinder containing an internal circumferential edge crack is considered. It is assumed that the problem is axisymmetric with regard to the crack geometry and the loading, and that the inertia effects are negligible. The problem is solved for a cylinder which is suddenly cooled from inside. First the transient temperature and stress distributions in an uncracked cylinder are calculated. By using the equal and opposite of this thermal stress as the crack surface traction in the isothermal cylinder the crack problem is then solved and the stress intensity factor is calculated. The numerical results are obtained as a function of the Fourier number tD/b(2) representing the time for various inner-to-outer radius ratios and relative crack depths, where D and b are respectively the coefficient of diffusivity and the outer radius of the cylinder.

Electromagnetic Invisibility of Elliptic Cylinder Cloaks

International Nuclear Information System (INIS)

Kan, Yao; Chao, Li; Fang, Li

2008-01-01

Structures with unique electromagnetic properties are designed based on the approach of spatial coordinate transformations of Maxwell's equations. This approach is applied to scheme out invisible elliptic cylinder cloaks, which provide more feasibility for cloaking arbitrarily shaped objects. The transformation expressions for the anisotropic material parameters and the field distribution are derived. The cloaking performances of ideal and lossy elliptic cylinder cloaks are investigated by finite element simulations. It is found that the cloaking performance will degrade in the forward direction with increasing loss. (fundamental areas of phenomenology (including applications))

Cylinder wakes in flowing soap films

International Nuclear Information System (INIS)

Vorobieff, P.; Ecke, R.E.; Vorobieff, P.

1999-01-01

We present an experimental characterization of cylinder wakes in flowing soap films. From instantaneous velocity and thickness fields, we find the vortex-shedding frequency, mean-flow velocity, and mean-film thickness. Using the empirical relationship between the Reynolds and Strouhal numbers obtained for cylinder wakes in three dimensions, we estimate the effective soap-film viscosity and its dependence on film thickness. We also compare the decay of vorticity with that in a simple Rankine vortex model with a dissipative term to account for air drag. copyright 1999 The American Physical Society

Comparison of panoramic radiograph with cone-beam computed tomography in assessment of maxillary sinus floor and nasal floor

Directory of Open Access Journals (Sweden)

Vijay Kumar Bokkasam

2015-01-01

Full Text Available Introduction: Panoramic radiograph is frequently prescribed by dentists for implant planning and, hence, accurate assessment of anatomical structures in panoramic radiograph is of utmost importance. Aims: The aim of the present study is to know the accuracy of panoramic radiograph in assessment of relationship between maxillary sinus floor and posterior teeth roots, and the distance from alveolar crest to nasal floor by comparing it with that of cone-beam computed tomographic (CBCT image. Materials and Methods: Panoramic and CBCT images of 30 patients were analyzed. The topographic relationship of each root of posterior teeth to the maxillary sinus floor was evaluated and classified into three classes. The distance from the peak point on maxillary alveolar crest to nasal floor was measured in panoramic radiograph as well as in CBCT image. All the measurements were made by built-in measurement tools. Results: Class 1 roots in panoramic radiograph showed high agreement (86% with CBCT image, followed by class 0 (76%. There was a significant difference in the measurements of alveolar bone height (ABH in the nasal floor region with a P value of 0.018. Conclusion: Panoramic radiograph is reliable in assessment of nasal floor and maxillary sinus, provided position of the patient, distortion, and the inherent magnification factor are taken into consideration.

Numerical simulation coupling with experimental study on the non-uniform of each cylinder gas exchange and working processes of a multi-cylinder gasoline engine under transient conditions

International Nuclear Information System (INIS)

Zhou, Feng; Fu, Jianqin; Shu, Jun; Liu, Jingping; Wang, Shuqian; Feng, Renhua

2016-01-01

Highlights: • An approach is presented to detect the CTCV of engine under transient conditions. • The range and influence factors of CTCV of engine performances were revealed. • The maximum relative deviation of IMEP in each cylinder is larger than ±30%. • There appears a symmetry relation between CTCV of RGF and excess air coefficient. - Abstract: Cylinder-to-cylinder variation is unavoidable in multi-cylinder engine and has a severe impact on engine performance. To explore the cylinder-to-cylinder variation of engine under transient conditions, a hybrid method of dynamic signal measurement coupling with gas dynamics and thermodynamics processes simulation is presented to detect the parameters of engine. Then, this method is applied to an automobile engine under road test conditions, and the continuous state and performance parameters of each cylinder were obtained from cycle to cycle. On this basis, the range and influence factors of non-uniform of engine performance parameters were analyzed. The results show that, under transient conditions, the relative deviation of excess air coefficient in each cylinder is within ±5%, which is mainly affected by intake average pressure in low to medium speed operating regions but influenced by exhaust pressure wave and residual gas fraction in high-speed and high-load operating regions. There appears a symmetry relation between the non-uniform of RGF and excess air coefficient. The relative deviation of indicated mean effective pressure in each cylinder depends largely on the gas exchange performance, including excess air coefficient and residual gas fraction, and the maximum is larger than ±30%.

Three-dimensional vortex flow near the endwall of a short cylinder in crossflow: Stepped-diameter circular cylinder

International Nuclear Information System (INIS)

Chen, S.B.; Sanitjai, S.; Ghosh, K.; Goldstein, R.J.

2012-01-01

The effect of geometry on the flow around a cylinder in crossflow is investigated in this study. Three different stepped-diameter circular cylinders (SDCC s) with varying step heights are used. Extensive flow visualization using the oil-lampblack and smoke-wire techniques and near wake velocity measurements using a hotwire anemometer reveal complex secondary flows on and around the SDCC. Six vortices are observed in the horseshoe vortex system near the cylinder–endwall junction and six additional vortices are found in the step-induced vortex system on the step surface. Based on these experimental results, new secondary flow models are proposed. The step-induced vortices separate from the step surface at both sides and move toward the endwall, washing down the sides of the top/bottom larger diameter cylinders and interact with the separated shear layer and horseshoe vortices. In this process, they modify the near wake flow significantly: they produce an increase in velocity near the endwall region (below the step) and a decrease in velocity near the mid-span region, even altering the oscillatory behavior of the wake. - Highlights: ► Extensive flow visualization for stepped-diameter circular cylinders in crossflow. ► Six vortices in the horseshoe vortex system near the base. ► Six additional step-induced vortices on the upstream symmetry plane of step surface. ► Power spectral analysis for u′ shows oscillatory nature of the wake.

Stresses from pressure, radial, and moment loads in cylinder-to-cylinder vessel by a finite plate method

International Nuclear Information System (INIS)

Brown, S.J.; Fox, M.E.

1977-08-01

A structural problem that has received continued interest and development over the last several decades is the determination of stresses in two normally intersecting cylindrical shells subjected to internal pressure and external loading. In nuclear pressure vessels the external loading of the vessel through the attachment is encountered in thermal interaction, seismic loading and various postulated rupture or failure mechanisms. A simple technique, the Finite Plate Method, (FPM) is presented to analyze stresses in cylinder-to-cylinder junctures. The approach uses shallow shell formulations and a three term series expansion plate formulation, which limits the range of applicability. It is felt that the value of the method is its accuracy, economy, and ease in modeling a structure which falls within the range of applicability. Another appealing feature of the method is that its simplistic approach of superposition of results permits an easy extension to include additional loads not treated. For those mechanical loadings not developed, it is felt that their effect can either be accounted for by the mechanisms discussed or by simple calculations. Generally, the stresses resulting from torsional or transverse shear are small compared to the loads discussed, however, these shear effects may be included. Finally, in the instance of thermal stress within the cylinder-to-cylinder structure, it has been shown in an unpublished study by Brown that the FPM yields very good results for the range of curvatures discussed

Imaging pelvic floor disorders. 2. rev. ed.

International Nuclear Information System (INIS)

Stoker, Jaap; Taylor, Stuart A.; DeLancey, John O.L.

2008-01-01

This volume builds on the success of the first edition of imaging pelvic floor disorders and is aimed at those practitioners with an interest in the imaging, diagnosis and treatment of pelvic floor dysfunction. Concise textual information from acknowledged experts is complemented by high-quality diagrams and images to provide a thorough update of this rapidly evolving field. Introductory chapters fully elucidate the anatomical basis underlying disorders of the pelvic floor. State of the art imaging techniques and their application in pelvic floor dysfunction are then discussed in detail. Additions since the first edition include consideration of the effect of aging and new chapters on perineal ultrasound, functional MRI and MRI of the levator muscles. The closing sections of the book describe the modern clinical management of pelvic floor dysfunction, including prolapse, urinary and faecal incontinence and constipation, with specific emphasis on the integration of diagnostic and treatment algorithms. (orig.)

Imaging pelvic floor disorders. 2. rev. ed.

Energy Technology Data Exchange (ETDEWEB)

Stoker, Jaap [Amsterdam Univ. (Netherlands). Dept. of Radiology; Taylor, Stuart A. [University College Hospital, London (United Kingdom). Dept. of Specialist X-Ray; DeLancey, John O.L. (eds.) [Michigan Univ., Ann Arbor, MI (United States). L4000 Women' s Hospital

2008-07-01

This volume builds on the success of the first edition of imaging pelvic floor disorders and is aimed at those practitioners with an interest in the imaging, diagnosis and treatment of pelvic floor dysfunction. Concise textual information from acknowledged experts is complemented by high-quality diagrams and images to provide a thorough update of this rapidly evolving field. Introductory chapters fully elucidate the anatomical basis underlying disorders of the pelvic floor. State of the art imaging techniques and their application in pelvic floor dysfunction are then discussed in detail. Additions since the first edition include consideration of the effect of aging and new chapters on perineal ultrasound, functional MRI and MRI of the levator muscles. The closing sections of the book describe the modern clinical management of pelvic floor dysfunction, including prolapse, urinary and faecal incontinence and constipation, with specific emphasis on the integration of diagnostic and treatment algorithms. (orig.)

Rotating shield ceiling for the compact ignition tokamak test cell

International Nuclear Information System (INIS)

Commander, J.C.

1986-01-01

For the next phase of the United States fusion program, a compact, high-field, toroidal ignition machine with liquid nitrogen cooled copper coils, designated the Compact Ignition Tokamak (CIT), is proposed. The CIT machine will be housed in a test cell with design features developed during preconceptual design. Configured as a right cylinder, the selected test cell design features: a test cell and basement with thick concrete shielding walls, and floor; leak tight tritium seals; and operational characteristics well suited to the circular CIT machine configuration and radially oriented ancillary equipment and systems

Floor heating maximizes residents` comfort

Energy Technology Data Exchange (ETDEWEB)

Tirkkanen, P.; Wikstroem, T.

1996-11-01

Storing heat in floors by using economical night-time electricity does not increase the specific consumption of heating. According to studies done by IVO, the optimum housing comfort is achieved if the room is heated mainly by means of floor heating that is evened out by window or ceiling heating, or by a combination of all three forms of heating. (orig.)

An online ID identification system for liquefied-gas cylinder plant

Science.gov (United States)

He, Jin; Ding, Zhenwen; Han, Lei; Zhang, Hao

2017-11-01

An automatic ID identification system for gas cylinders' online production was developed based on the production conditions and requirements of the Technical Committee for Standardization of Gas Cylinders. A cylinder ID image acquisition system was designed to improve the image contrast of ID regions on gas cylinders against the background. Then the ID digits region was located by the CNN template matching algorithm. Following that, an adaptive threshold method based on the analysis of local average grey value and standard deviation was proposed to overcome defects of non-uniform background in the segmentation results. To improve the single digit identification accuracy, two BP neural networks were trained respectively for the identification of all digits and the easily confusable digits. If the single digit was classified as one of confusable digits by the former BP neural network, it was further tested by the later one, and the later result was taken as the final identification result of this single digit. At last, the majority voting was adopted to decide the final identification result for the 6-digit cylinder ID. The developed system was installed on a production line of a liquefied-petroleum-gas cylinder plant and worked in parallel with the existing weighing step on the line. Through the field test, the correct identification rate for single ID digit was 94.73%, and none of the tested 2000 cylinder ID was misclassified through the majority voting.

78 FR 30329 - Multilayered Wood Flooring from China

Science.gov (United States)

2013-05-22

...)] Multilayered Wood Flooring from China AGENCY: United States International Trade Commission. ACTION: Notice of...-1179 (Final) concerning multilayered wood flooring (``MLWF'') from China. For further information... reconsider ``its decision not to investigate domestic producers of hardwood plywood used for flooring'' 2. to...

Pelvic floor function during and after first pregnancy

NARCIS (Netherlands)

Brummen, H.J. van

2006-01-01

This study evaluated the effects the first pregnancy and childbirth on the pelvic floor. Pregnancy and vaginal delivery can negatively affect pelvic floor function. Micturition symptoms, defecation symptoms and sexual dysfunction are all signs of an impaired pelvic floor function. These symptoms are

Synthesis of new aluminum nano hybrid composite liner for energy saving in diesel engines

International Nuclear Information System (INIS)

Tiruvenkadam, N.; Thyla, P.R.; Senthilkumar, M.; Bharathiraja, M.; Murugesan, A.

2015-01-01

Highlights: • Nano hybrid composite cylinder liner (NL) was developed to replace cast iron liner. • NL improved engine performance, combustion and reduced emissions except NO x . • Teardown analysis provides the suitability of NL for diesel engine. • The developed aluminum NL saved 43.75% of weight than cast iron cylinder liner. - Abstract: This work aims to replace the conventional cast iron cylinder liner (CL) in diesel engine by introducing lightweight aluminum (Al) 6061 nano hybrid composite cylinder liner (NL) by analyzing the performance, combustion, and emission characteristics of an engine. NL was fabricated by bottom pouring stir casting technique with nano- and micro-reinforcement materials. Experimental results proved that the use of NL increased brake thermal efficiency, in-cylinder pressure, heat release rate, and reduced carbon monoxide, hydrocarbon, and smoke emission in comparison with CL. However, oxides of nitrogen slightly increased with the use of the new liner. No differences in wear or other issues were noted during the engine teardown after 1 year of operation and 2000 h of running. Thus, NL has been recommended to replace the CL to save the energy and to reap environmental benefits

Gait of dairy cows on floors with different slipperiness.

Science.gov (United States)

Telezhenko, E; Magnusson, M; Bergsten, C

2017-08-01

This study assessed the slip resistance of different types of solid flooring in cattle housing using a range of technical tests and gait analysis. Dynamic and static coefficient of friction, skid resistance, and abrasiveness were tested on concrete flooring with a smooth finish, a grooved pattern, or a tamped pattern, acid-resistant mastic asphalt, soft rubber mats, and a worn slatted concrete floor. Coefficients of friction and skid resistance were tested under clean and slurry-soiled conditions. Linear kinematic variables were assessed in 40 cows with trackway measurements after the cows passed over the floors in a straight walk. All gait variables were assessed as deviations from those obtained on the slatted concrete floor, which was used as a baseline. The coefficient of friction tests divided the floors into 3 categories: concrete flooring, which had a low coefficient of friction (0.29-0.41); mastic asphalt flooring, which had medium values (0.38-0.45); and rubber mats, which had high values (0.49-0.57). The highest abrasion (g/10 m) was on the asphalt flooring (4.48), and the concrete flooring with a tamped pattern had significantly higher abrasiveness (2.77) than the other concrete floors (1.26-1.60). Lowest values on the skid-resistance tests (dry/wet) were for smooth concrete (79/35) and mastic asphalt (65/47), especially with a slurry layer on the surface. Gait analysis mainly differentiated floors with higher friction and abrasion by longer strides and better tracking. Step asymmetry was lower on floors with high skid-resistance values. The most secure cow gait, in almost every aspect, was observed on soft rubber mats. Relationships between gait variables and physical floor characteristics ranged from average to weak (partial correlations 0.54-0.16). Thus, none of the physical characteristics alone was informative enough to characterize slip resistance. With reference to gait analysis, the abrasiveness of the hard surfaces was more informative than the

Mapping of multi-floor buildings: A barometric approach

DEFF Research Database (Denmark)

Özkil, Ali Gürcan; Fan, Zhun; Xiao, Jizhong

2011-01-01

This paper presents a new method for mapping multi5floor buildings. The method combines laser range sensor for metric mapping and barometric pressure sensor for detecting floor transitions and map segmentation. We exploit the fact that the barometric pressure is a function of the elevation......, and it varies between different floors. The method is tested with a real robot in a typical indoor environment, and the results show that physically consistent multi5floor representations are achievable....

A pneumatic cylinder driving polyhedron mobile mechanism

Science.gov (United States)

Ding, Wan; Kim, Sung-Chan; Yao, Yan-An

2012-03-01

A novel pneumatic cylinder driving polyhedron mobile mechanism is proposed in this paper. The mechanism is comprised of 5 tetrahedrons which includes a pneumatic cylinder in each edge. It locomotes by rolling and the rolling principle refers to the center of mass (CM) of the mechanism moved out of the supporting area and let it tip over through the controlling of the motion sequence of these cylinders. Firstly, the mathematical model is built to analysis the relation between the configuration and the CM of the mechanism. Then, a binary control strategy is developed to simplify and improve the control of this mobile mechanism. After that, dynamic simulation is performed to testify the analytical validity and feasibility of the rolling gaits. At last, a prototype is fabricated to achieve the rolling successfully to demonstrate the proposed concept.

Bursting pressure of autofrettaged cylinders with inclined external cracks

Energy Technology Data Exchange (ETDEWEB)

Seifi, Rahman, E-mail: rseifi@basu.ac.ir [Mechanical Engineering Department, Faculty of Engineering, Bu-Ali Sina University, Hamedan (Iran, Islamic Republic of); Babalhavaeji, Majid [Mechanical Engineering Department, Faculty of Engineering, Bu-Ali Sina University, Hamedan (Iran, Islamic Republic of)

2012-01-15

Autofrettaging a pressure vessel improves its pressure capacity. This is reliable if there isn't any crack or other type of flaws. In this paper, the effects of external surface cracks on bursting pressure of autofrettaged cylinders are studied. It is observed that bursting pressure decreases considerably (up to 30%) due to external cracks in the cylinders without autofrettage. This reduction increases for high levels of the applied autofrettage. External axial cracks have more effects than inclined cracks. Comparing experimental and numerical results show that the numerical methods can acceptably predict the bursting pressure of the autofrettaged cracked cylinders. These predictions are valid when the fracture parameter (J-Integral) is calculated from the modified equation that takes into account the effects of residual stresses. - Highlights: Black-Right-Pointing-Pointer Modified J-Integral can be used for study of autofrettaged cracked cylinders. Black-Right-Pointing-Pointer External axial cracks reduce considerably the pressure capacity of cylinders. Black-Right-Pointing-Pointer External circumferential cracks have not considerable effects on bursting pressure. Black-Right-Pointing-Pointer Autofrettage has contrary effects on external crack in compared with internal crack.

Formation of whispering gallery modes by scattering of an electromagnetic plane wave by two cylinders

Energy Technology Data Exchange (ETDEWEB)

Abramov, Arnold, E-mail: qulaser@gmail.com [Kuang-Chi Institute of Advanced Technology, Shenzhen, 518057 (China); Kostikov, Alexander [Donbass State Engineering Academy, 84303, Kramatorsk, Donetsk (Ukraine)

2017-03-26

We report the effect of scattering of electromagnetic plane waves by two cylinders on whispering gallery mode (WGM) formation in a cylinder. WGM can occur because of the presence of additional cylinder scatterers at specific location, while WGMs can only form in a single cylinder for specific cylinder radius and/or wavelength values, the matching accuracy required would be much greater than that required in our model for the additional cylinders locations. Analysis of the general solution to the problem showed that the effect can be explained by the interference of waves scattered by additional cylinders and incident on the main cylinder. - Highlights: • We consider scattering of electromagnetic plane waves by two cylinders. • WGMs occur because of the presence of additional cylinder at specific location. • The accuracy for the locations is much less than required for specific values of single cylinder. • The interference of waves scattered by additional cylinders and incident on the main is responsible for the effect.

The procedure of selecting the best construction equipment by the set of its quantitative characteristics

Directory of Open Access Journals (Sweden)

Romanov Petr

2017-01-01

Full Text Available Today’s construction projects are highly mechanized. That#x2019;s why selection of right equipment has always been a key factor in the success of any construction project. This decision is typically made by comparison of equipment feature, productivity, capacity and cost. The article describes the approach to selecting the best set of construction equipment from the available options by the set of its quantitative characteristics. It is proposed to carry out the evaluation of options and selection of the best option based on the method of spectral analysis. The article presents the results of the selection of the most appropriate floor screed conveyor for purchasing by construction company using the specified method.

Flow around a confined cylinder: LES and PIV study

Directory of Open Access Journals (Sweden)

Palkin Egor

2017-01-01

Full Text Available We study the flow over a cylinder placed between two parallel rigid walls using Large-eddy simulations and Particle Image Velocimetry. The Reynolds number based on the inflow velocity and diameter of the cylinder is 3750 corresponding to the subcritical regime with laminar separation. Three-dimensional visualization shows the presence of the horseshoe vortex system prior to the cylinder. The comparison of time-averaged velocity fields and fluctuations shows good agreement between simulations and experiments. Spectral analysis suggests the presence of low-frequency modulations of the recirculating bubble.

Collision Probabilities for Finite Cylinders and Cuboids

Energy Technology Data Exchange (ETDEWEB)

Carlvik, I

1967-05-15

Analytical formulae have been derived for the collision probabilities of homogeneous finite cylinders and cuboids. The formula for the finite cylinder contains double integrals, and the formula for the cuboid only single integrals. Collision probabilities have been calculated by means of the formulae and compared with values obtained by other authors. It was found that the calculations using the analytical formulae are much quicker and give higher accuracy than Monte Carlo calculations.

Characterization of a PET-NEMA/IEC body phantom for quality control tests of PET/CT equipment

International Nuclear Information System (INIS)

Oliveira, Cassio M.; Vieira, Igor F.; Lima, Fernando R.A.; Sa, Lidia V. de

2011-01-01

The Brazilian Sanitary Agency from Ministry of Health requires that all PET/CT equipment must undergo minimal quality control tests using manufacturer simulators. The PET-NEMA/IEC body phantom is recommended by the IEC and NEMA to perform acceptance testing and quality control in PET/CT equipment according to specific protocols. It is essential that all simulator components (spheres and body) are properly characterized in relation to their size and internal structure volumes, since they are used to calculate the overall activity concentration and the total weight. The objective of this work was characterize a PET-NEMA/IEC body phantom for the true reconstruction in computational modeling and correct analysis of experimental results. The simulator is basically composed of three structures: the body (simulating a portion of the chest), an inner cylinder (simulating the lung tissue) and a top cover in which are coupled spheres of different sizes simulating 'hot' (tumors) and cold lesions. The spheres were evaluated in terms of volume. The same evaluations were performed with the body of the simulator and the inner cylinder, beyond of analysis of their weights (filled with water) and wall thickness. The data showed that the total weight of the simulator with all its internal structures is 12.5 kg and the volume of the 'hot' and 'cold' spheres are approximately equal to those presented by the manufacturer. The inner cylinder volume showed a significant difference between the measured and the presented in the manual. The results were used for reconstruction of the simulator in computational modeling using the code GATE. (author)

A numerical investigation of sub-wavelength resonances in polygonal metamaterial cylinders

DEFF Research Database (Denmark)

Arslanagic, Samel; Breinbjerg, Olav

2009-01-01

The sub-wavelength resonances, known to exist in metamaterial radiators and scatterers of circular cylindrical shape, are investigated with the aim of determining if these resonances also exist for polygonal cylinders and, if so, how they are affected by the shape of the polygon. To this end, a set...... of polygonal cylinders excited by a nearby electric line current is analyzed numerically and it is shown, through detailed analysis of the near-field distribution and radiation resistance, that these polygonal cylinders do indeed support sub-wavelength resonances similar to those of the circular cylinders...

Life cycle inventory of manufacturing prefinished engineered wood flooring in eastern U.S. with comparison to solid strip wood flooring

Science.gov (United States)

Richard D. Bergman; Scott A. Bowe

2011-01-01

Building products have come under increased scrutiny because of environmental impacts from their manufacture. Our study followed the life cycle inventory approach for prefinished engineered wood flooring in the eastern US and compared the results with those of solid strip wood flooring. Our study surveyed five engineered wood flooring manufacturers in the eastern US....

Experimental Verification of an Instrument to Test Flooring Materials

Science.gov (United States)

Philip, Rony; Löfgren, Hans, Dr

2018-02-01

The focus of this work is to validate the fluid model with different flooring materials and the measurements of an instrument to test flooring materials and its force attenuating capabilities using mathematical models to describe the signature and coefficients of the floor. The main contribution of the present work focus on the development of a mathematical fluid model for floors. The aim of the thesis was to analyze, compare different floor materials and to study the linear dynamics of falling impacts on floors. The impact of the hammer during a fall is captured by an accelerometer and response is collected using a picoscope. The collected data was analyzed using matlab least square method which is coded as per the fluid model. The finding from this thesis showed that the fluid model works with more elastic model but it doesn’t work for rigid materials like wood. The importance of parameters like velocity, mass, energy loss and other coefficients of floor which influences the model during the impact of falling on floors were identified and a standardized testing method was set.

Process for the dismantling of buried equipment, with a contamination risk and eventually irradiating, and intervention enclosure for this process

International Nuclear Information System (INIS)

Bodin, F.; Saublet, J.C.

1991-01-01

Dismantling of buried equipment, for instance abandoned effluent pipes,is made by unitary sections under mobile enclosure with a self-supporting structure and a floor provided with a long central aperture giving access to the section to dismantle

Transient thermal stresses in circular cylinder under intermittently sudden heat generation

International Nuclear Information System (INIS)

Sugano, Y.; Saito, K.; Takeuti, Y.

1975-01-01

The thermal stresses associated with the transient temperature distribution arising in a circular cylinder under intermittently changing sudden heat generation over a finite band and with heat loss to a surrounding medium on the remainder of the cylinder surface are exactly analysed. For the first time the temperature field in a circular cylinder under sudden heat generation over a finite band of the cylinder surface is determined by combined use of Fourier cosine, Laplace transforms in axial position and time, respectively. Secondly it is assumed that the temperature fields in a circular cylinder subjected to heat generation Qsub(i) (i=0, 1, 2, ...) independently over a finite band are given by T 0 (r,z,t), T 1 (r,z,t), T 2 (r,z,t),... respectively. Tsub(i)(r,z,t) indicates the temperature field before the i-th heat generation Qsub(i). The thermal stresses associated with the temperature field described above are analysed by using the Hoyle stress functions. Numerical calculations are carried out for the extensive case of the ratio of the heat-generating length to the diameter of cylinder. It is found that the time in which the maximum stresses occur on the cylinder surface does not depend on the heat-generating length-to-diameter ratio

Stokes flow past a swarm of porous circular cylinders with Happel ...

Indian Academy of Sciences (India)

The problem of creeping flow past a swarm of porous circular cylinders with Happel and Kuwabara boundary conditions is investigated. The Brinkman equation for the flow inside the porous cylinder and the Stokes equation outside the porous cylinder in their stream function formulations are used. The force experienced by ...

Effects of fire exposure on integrity of UF6 shipping cylinders

International Nuclear Information System (INIS)

Barlow, C.R.; Ziehlke, K.T.; Pryor, W.A.

1985-01-01

Two 2-1/2-ton steel cylinders for the transport of uranium hexafluoride within the United States nuclear fuel enrichment cycle were involved in a warehouse fire where portions of the cylinders were estimated to have reached a temperature of 1600 0 F (870 0 C). The cylinders were empty at the time of the fire and therefore were not in protective overpacks in which full product cylinders are handled while in transit. Hydrostatic tests to failure showed that the integrity of the cylinders was not degraded by exposure to the temperatures generated by the fire. They withstood test pressures in excess of 10 times the design pressure, and showed a volume expansion of 30% above the original capacity before rupture in a completely ductile fashion. Reference CAPE-323. 9 figs

Perturbative calculations of flow patterns in free convection between coaxial cylinders. Non-linear temperature dependences of the fluid properties

International Nuclear Information System (INIS)

Navarro, J. A.; Madariaga, J. A.; Santamaria, C. M.; Saviron, J. M.

1980-01-01

10 refs. Flow pattern calculations in natural convection between two vertical coaxial cylinders are reported. It is assumed trough the paper. that fluid properties, viscosity, thermal conductivity and density, depend no-linearly on temperature and that the aspects (height/radius) ratio of the cylinders is high. Velocity profiles are calculated trough a perturbative scheme and analytic results for the three first perturbation orders are presented. We outline also an iterative method to estimate the perturbations on the flow patterns which arise when a radial composition gradient is established by external forces in a two-component fluid. This procedure, based on semiempirical basis, is applied to gaseous convection. The influence of the molecules gas properties on tho flow is also discussed. (Author) 10 refs

Patients with Pelvic Floor Muscle Spasm Have a Superior Response to Pelvic Floor Physical Therapy at Specialized Centers.

Science.gov (United States)

Polackwich, Alan Scott; Li, Jianbo; Shoskes, Daniel A

2015-10-01

Chronic prostatitis/chronic pelvic pain syndrome is a common condition that often requires multimodal therapy. Patients with chronic pelvic pain syndrome have a high incidence of pelvic floor spasm, which can be treated with pelvic floor physical therapy. However, this is a specialized skill. We compared outcomes of pelvic floor physical therapy as part of multimodal therapy in patients with chronic pelvic pain syndrome between those treated at our institution and elsewhere. We identified patients from our chronic pelvic pain syndrome registry with pelvic floor spasm who were seen between 2010 and 2014 for more than 1 visit. Patient phenotype was assessed with the UPOINT system and symptom severity was determined by the National Institutes of Health CPSI. A 6-point decrease in CPSI was used to define patient improvement. A total of 82 patients fit the study criteria. Mean age was 41.6 years (range 19 to 75) and median symptom duration was 24 months (range 3 to 240). Mean CPSI was 26.8 (range 10 to 41), the median number of positive UPOINT domains was 3 (range 1 to 6) and 27 patients (32.9%) were treated locally. At followup 9 patients had refused pelvic floor physical therapy, and 24 and 48 had undergone pelvic floor physical therapy elsewhere and at CCF, respectively. The mean change in CPSI was 1.11 ± 4.1 in patients who refused, -3.46 ± 6.7 in those treated elsewhere and -11.3 ± 7.0 in those treated at CCF (p physical therapy at CCF (OR 4.23, p = 0.002) and symptom duration (OR 0.52, p = 0.03) predicted improvement. Pelvic floor physical therapy can be effective for chronic pelvic pain syndrome in patients with pelvic floor spasm. However, the outcome depends on specialty training and experience of therapists. Copyright © 2015 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

Investigation of Floor Surface Finishes for Optimal Slip Resistance Performance

Directory of Open Access Journals (Sweden)

In-Ju Kim

2018-03-01

Full Text Available Background: Increasing the slip resistance of floor surfaces would be desirable, but there is a lack of evidence on whether traction properties are linearly correlated with the topographic features of the floor surfaces or what scales of surface roughness are required to effectively control the slipperiness of floors. Objective: This study expands on earlier findings on the effects of floor surface finishes against slip resistance performance and determines the operative ranges of floor surface roughness for optimal slip resistance controls under different risk levels of walking environments. Methods: Dynamic friction tests were conducted among three shoes and nine floor specimens under wet and oily environments and compared with a soapy environment. Results: The test results showed the significant effects of floor surface roughness on slip resistance performance against all the lubricated environments. Compared with the floor-type effect, the shoe-type effect on slip resistance performance was insignificant against the highly polluted environments. The study outcomes also indicated that the oily environment required rougher surface finishes than the wet and soapy ones in their lower boundary ranges of floor surface roughness. Conclusion: The results of this study with previous findings confirm that floor surface finishes require different levels of surface coarseness for different types of environmental conditions to effectively manage slippery walking environments. Collected data on operative ranges of floor surface roughness seem to be a valuable tool to develop practical design information and standards for floor surface finishes to efficiently prevent pedestrian fall incidents. Keywords: floor surface finishes, operational levels of floor surface roughness, slip resistance, wet, soapy and oily environments

An architecture for agile shop floor control systems

DEFF Research Database (Denmark)

Langer, Gilad; Alting, Leo

2000-01-01

as shop floor control. This paper presents the Holonic Multi-cell Control System (HoMuCS) architecture that allows for design and development of holonic shop floor control systems. The HoMuCS is a shop floor control system which is sometimes referred to as a manufacturing execution system...

Four-Cylinder Stirling-Engine Computer Program

Science.gov (United States)

Daniele, C. J.; Lorenzo, C. F.

1986-01-01

Computer program developed for simulating steady-state and transient performance of four-cylinder Stirling engine. In model, four cylinders interconnected by four working spaces. Each working space contains seven volumes: one for expansion space, heater, cooler, and compression space and three for regenerator. Thermal time constant for regenerator mass associated with each regenator gas volume. Former code generates results very quickly, since it has only 14 state variables with no energy equation. Current code then used to study various aspects of Stirling engine in much more detail. Program written in FORTRAN IV for use on IBM 370 computer.

An ignimbrite caldera from the bottom up: Exhumed floor and fill of the resurgent Bonanza caldera, Southern Rocky Mountain volcanic field, Colorado

Science.gov (United States)

Lipman, Peter W.; Zimmerer, Matthew J.; McIntosh, William C.

2015-01-01

Among large ignimbrites, the Bonanza Tuff and its source caldera in the Southern Rocky Mountain volcanic field display diverse depositional and structural features that provide special insights concerning eruptive processes and caldera development. In contrast to the nested loci for successive ignimbrite eruptions at many large multicyclic calderas elsewhere, Bonanza caldera is an areally isolated structure that formed in response to a single ignimbrite eruption. The adjacent Marshall caldera, the nonresurgent lava-filled source for the 33.9-Ma Thorn Ranch Tuff, is the immediate precursor for Bonanza, but projected structural boundaries of two calderas are largely or entirely separate even though the western topographic rim of Bonanza impinges on the older caldera. Bonanza, source of a compositionally complex regional ignimbrite sheet erupted at 33.12 ± 0.03 Ma, is a much larger caldera system than previously recognized. It is a subequant structure ∼20 km in diameter that subsided at least 3.5 km during explosive eruption of ∼1000 km3 of magma, then resurgently domed its floor a similar distance vertically. Among its features: (1) varied exposure levels of an intact caldera due to rugged present-day topography—from Paleozoic and Precambrian basement rocks that are intruded by resurgent plutons, upward through precaldera volcanic floor, to a single thickly ponded intracaldera ignimbrite (Bonanza Tuff), interleaved landslide breccia, and overlying postcollapse lavas; (2) large compositional gradients in the Bonanza ignimbrite (silicic andesite to rhyolite ignimbrite; 60%–76% SiO2); (3) multiple alternations of mafic and silicic zones within a single ignimbrite, rather than simple upward gradation to more mafic compositions; (4) compositional contrasts between outflow sectors of the ignimbrite (mainly crystal-poor rhyolite to east, crystal-rich dacite to west); (5) similarly large compositional diversity among postcollapse caldera-fill lavas and resurgent

Lattice Boltzmann simulation of viscoelastic flow past a confined free rotating cylinder

Science.gov (United States)

Xia, Yi; Zhang, Peijie; Lin, Jianzhong; Ku, Xiaoke; Nie, Deming

2018-05-01

To study the dynamics of rigid body immersed in viscoelastic fluid, an Oldroyd-B fluid flow past an eccentrically situated, free rotating cylinder in a two-dimensional (2D) channel is simulated by a novel lattice Boltzmann method. Two distribution functions are employed, one of which is aimed to solve Navier-Stokes equation and the other to the constitutive equation, respectively. The unified interpolation bounce-back scheme is adopted to treat the moving curved boundary of cylinder, and the novel Galilean invariant momentum exchange method is utilized to obtain the hydrodynamic force and torque exerted on the cylinder. Results show that the center-fixed cylinder rotates inversely in the direction where a cylinder immersed in Newtonian fluid do, which generates a centerline-oriented lift force according to Magnus effect. The cylinder’s eccentricity, flow inertia, fluid elasticity and viscosity would affect the rotation of cylinder in different ways. The cylinder rotates more rapidly when located farther away from the centerline, and slows down when it is too close to the wall. The rotation frequency decreases with increasing Reynolds number, and larger rotation frequency responds to larger Weissenberg number and smaller viscosity ratio, indicating that the fluid elasticity and low solvent viscosity accelerates the flow-induced rotation of cylinder.

Flow and flow-induced vibration of a square array of cylinders in steady currents

Energy Technology Data Exchange (ETDEWEB)

Zhao, Ming [School of Computing, Engineering and Mathematics, University of Western Sydney, Locked Bag 1797, Penrith, NSW 2751 (Australia); Cheng, Liang; An, Hongwei; Tong, Feifei, E-mail: m.zhao@uws.edu.au [School of Civil, Environmental and Mining Engineering, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009 (Australia)

2015-08-15

Flow and flow-induced vibration of a square array of cylinders are investigated by two-dimensional numerical simulations. Flow past 36 cylinders in an inline arranged square array and 33 cylinders in a staggered arranged square array is firstly simulated, for Re = 100 and the spacing ratios of L/D = 1.5, 2, 3, 4, 5. Only one vortex street is observed in the wake of the cylinder array when the spacing ratio is 1.5 in the inline arrangement and 1.5 and 2 in the staggered arrangement, indicating that the critical spacing ratio for the single-vortex street mode in the staggered arrangement is higher than that in the inline arrangement. The vortex shedding from the cylinders is suppressed at L/D = 3 for both inline and staggered arrangements. Vortex shedding from each individual cylinder is observed when L/D = 4. Flow-induced vibration of 36 cylinders in an inline square arrangement is studied for a constant Reynolds number of 100, two spacing ratios of 2 and 5, a constant mass ratio of 2.5 and a wide range of reduced velocities. It is found that for a spacing ratio of 2, the vibration of the cylinders in the four downstream columns does not start until the reduced velocity exceeds 4.5. The vibration of the cylinders progresses downstream with increasing reduced velocity. For a spacing ratio of 5, the vibrations of the cylinders in the most upstream column are similar to that of a single cylinder. The vibration amplitudes of the downstream cylinders peak at higher reduced velocities than that of a single cylinder. The maximum possible response amplitudes occur at the most downstream cylinders. (paper)

Dynamic Fracture Simulations of Explosively Loaded Cylinders

Energy Technology Data Exchange (ETDEWEB)

Arthur, Carly W. [Univ. of California, Davis, CA (United States). Dept. of Civil and Environmental Engineering; Goto, D. M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

2015-11-30

This report documents the modeling results of high explosive experiments investigating dynamic fracture of steel (AerMet® 100 alloy) cylinders. The experiments were conducted at Lawrence Livermore National Laboratory (LLNL) during 2007 to 2008 [10]. A principal objective of this study was to gain an understanding of dynamic material failure through the analysis of hydrodynamic computer code simulations. Two-dimensional and three-dimensional computational cylinder models were analyzed using the ALE3D multi-physics computer code.

Relaxation of Thick-Walled Cylinders and Spheres

DEFF Research Database (Denmark)

Saabye Ottosen, N.

1982-01-01

Using the nonlinear creep law proposed by Soderberg, (1936) closed-form solutions are derived for the relaxation of incompressible thick-walled spheres and cylinders in plane strain. These solutions involve series expressions which, however, converge very quickly. By simply ignoring these series...... expressions, extremely simple approximate solutions are obtained. Despite their simplicity these approximations possess an accuracy that is superior to approximations currently in use. Finally, several physical aspects related to the relaxation of cylinders and spheres are discussed...

Bristol cylinder. Vol. 3A - technical appraisal

Energy Technology Data Exchange (ETDEWEB)

1983-06-01

A consultants' report is presented on a UK funded wave energy device known as the Bristol Cylinder. A detailed engineering appraisal is given for each component and aspects of the device including installation, power generation and maintenance. Finally the discounted cost of energy from the device is assessed. For all topics the views of the consultants are compared with those of the team developing the Bristol Cylinder and where discrepancies occur, these are explained and discussed.

Corrosion of breached UF6 storage cylinders

International Nuclear Information System (INIS)

Barber, E.J.; Taylor, M.S.; DeVan, J.H.

1993-01-01

This paper describes the corrosion processes that occurred following the mechanical failure of two steel 14-ton storage cylinders containing depleted UF 6 . The failures both were traced to small mechanical tears that occurred during stacking of the cylinders. Although subsequent corrosion processes greatly extended the openings in the wall. the reaction products formed were quite protective and prevented any significant environmental insult or loss of uranium. The relative sizes of the two holes correlated with the relative exposure times that had elapsed from the time of stacking. From the sizes and geometries of the two holes, together with analyses of the reaction products, it was possible to determine the chemical reactions that controlled the corrosion process and to develop a scenario for predicting the rate of hydrolysis of UF 6 , the loss rate of HF, and chemical attack of a breached UF 6 storage cylinder

Comfort analysis of lightweight floor system

NARCIS (Netherlands)

Zegers, S.F.A.J.G.; Herwijnen, van F.; Randall, B.

2007-01-01

During the past 60 years, floor systems used in housing and office-buildings in the Netherlands were mostly made of concrete or other similar materials, These floor systems, which can be characterized as heavy, normally posed little problems concerning vibrations. In recent years, in light of

Floor Vibrations - as Induced and Reduced by Humans

DEFF Research Database (Denmark)

Pedersen, Lars

. As for dynamic loads focus is placed on heel impact excitation and actions of jumping people causing floor vibrations. As for interaction between stationary humans and the vibrating floor focus is on modelling humans as oscillating spring-mass-damper systems attached to the floor rather than as simple added mass...

Flow Features of Three Side-by-side Circular Cylinders at Low Reynolds Number

Directory of Open Access Journals (Sweden)

Liu Junkao

2016-01-01

Full Text Available In order to study the fluctuation of kinetic parameter of cylinder matrix in incompressible stationary flow, the flow fluid around three side-by-side circular cylinders are simulated using Immersed Boundary–Lattice Boltzmann method (IB-LBM. Drag and lift force of the three cylinders are investigated as the interval between each cylinder varied from zero to five times of the cylinder diameter. Five flow patterns are defined according to the vortices structure in the downstream of the cylinders. Power spectrum analysis of lift force is developed to explain the vortex patterns. Through the research, we find the strength and phase of the gap flow play an important role in the vortex formatting process. The vortices shedding from different cylinders neutralize and combine in the near wake, contributing a lot to the variation of forces.

Flooring-systems and their interaction with furniture and humans

DEFF Research Database (Denmark)

Frier, Christian; Pedersen, Lars; Andersen, Lars Vabbersgaard

2017-01-01

Flooring-system designs may be sensitive in terms of their vibrational performance due the risk that serviceability-limit-state problems may be encountered. For evaluating the vibrational performance of a flooring system at the design stage, decisions must be made by the engineer in charge...... of computations. Passive humans and/or furniture are often present on a floor. Typically, these masses and their way of interacting with the floor mass are ignored in predictions of vibrational behaviour of the flooring system. Utilizing a shell finite-element model, the paper explores and quantifies how non......-structural mass can influence central parameters describing the dynamic behaviour of the flooring system with focus on elevated non-structural mass. © 2017 The Authors. Published by Elsevier Ltd....

Extended Analytic Linear Model of Hydraulic Cylinder With Respect Different Piston Areas and Volumes

Directory of Open Access Journals (Sweden)

Petr KOŇAŘÍK

2009-06-01

Full Text Available Standard analytic linear model of hydraulic cylinder usually comes from assumptions of identical action piston areas on both sides of hydraulic cylinder (double piston rod and suitable operation point, which is usually chosen in the middle of piston. By reason of that volumes inside of cylinder are than same. Moreover for control of that arrangement of hydraulic cylinder, usually controlled by 4/3 servovalve, the same mount of flows comes in and comes out to each of chambers of hydraulic cylinder. Presented paper deal with development of extended form of analytic linear model of single piston rod hydraulic cylinder which respects different action piston areas and volumes inside of chambers of hydraulic cylinder and also two different input flows of hydraulic cylinder. In extended model are also considered possibilities of different dead volumes in hoses and intake parts of hydraulic cylinder. Dead volume has impact on damping of hydraulic cylinder. Because the system of hydraulic cylinder is generally presented as a integrative system with inertia of second order: eq , we can than obtain time constants and damping of hydraulic cylinder for each of analytic form model. The model has arisen for needs of model fractionation on two parts. Part of behaviour of chamber A and part of behaviour of chamber B of cylinder. It was created for the reason of analysis and synthesis of control parameters of regulation circuit of multivalve control concept of hydraulic drive with separately controlled chamber A and B which could be then used for.

Optimization of In-Cylinder Pressure Filter for Engine Research

Science.gov (United States)

2017-06-01

ARL-TR-8034 ● JUN 2017 US Army Research Laboratory Optimization of In-Cylinder Pressure Filter for Engine Research by Kenneth...Laboratory Optimization of In-Cylinder Pressure Filter for Engine Research by Kenneth S Kim, Michael T Szedlmayer, Kurt M Kruger, and Chol-Bum M...

In-depth Study on Cylinder Wake Controlled by Lorentz Force

International Nuclear Information System (INIS)

Zhang Hui; Fan Bao-Chun; Chen Zhi-Hua

2011-01-01

The underlying mechanisms of the electromagnetic control of cylinder wake are investigated and discussed. The effects of Lorentz force are found to be composed of two parts, one is its direct action on the cylinder (the wall Lorentz force) and the other is applied to the fluid (called the field Lorentz force) near the cylinder surface. Our results show that the wall Lorentz force can generate thrust and reduce the drag; the field Lorentz force increases the drag. However, the cylinder drag is dominated by the wall Lorentz force. In addition, the field Lorentz force above the upper surface decreases the lift, while the upper wall Lorentz force increases it. The total lift is dominated by the upper wall Lorentz force. (fundamental areas of phenomenology(including applications))

Method and apparatus for filling cryogenic liquid cylinders

International Nuclear Information System (INIS)

Remes, S.

1984-01-01

A method and apparatus are disclosed for filling a portable cryogenic liquid cylinder from a large stand tank. The invention employs a regulator valve to perform an automatic throttling function whereby the pressure in the liquid cylinder is maintained at a value slightly lower than the upstream pressure in the stand tank. This significantly reduces filling losses due to flashing

Sea-Floor geology and character of Eastern Rhode Island Sound West of Gay Head, Massachusetts

Science.gov (United States)

Poppe, L.J.; McMullen, K.Y.; Ackerman, S.D.; Blackwood, D.S.; Irwin, B.J.; Schaer, J.D.; Forrest, M.R.

2011-01-01

Gridded multibeam bathymetry covers approximately 102 square kilometers of sea floor in eastern Rhode Island Sound west of Gay Head, Massachusetts. Although originally collected for charting purposes during National Oceanic and Atmospheric Administration hydrographic survey H11922, these acoustic data and the sea-floor stations subsequently occupied to verify them (1) show the composition and terrain of the seabed, (2) provide information on sediment transport and benthic habitat, and (3) are part of an expanding series of studies that provide a fundamental framework for research and management activities (for example, windfarms and fisheries) along the Massachusetts inner continental shelf. Most of the sea floor in the study area has an undulating to faintly rippled appearance and is composed of bioturbated muddy sand, reflecting processes associated with sediment sorting and reworking. Shallower areas are composed of rippled sand and, where small fields of megaripples are present, indicate sedimentary environments characterized by processes associated with coarse bedload transport. Boulders and gravel were found on the floors of scour depressions and on top of an isolated bathymetric high where erosion has removed the Holocene marine sediments and exposed the underlying relict lag deposits of Pleistocene drift. The numerous scour depressions, which formed during storm-driven events, result in the juxtaposition of sea-floor areas with contrasting sedimentary environments and distinct gravel, sand, and muddy sand textures. This textural heterogeneity in turn creates a complex patchwork of habitats. Our observations of local variations in community structure suggest that this small-scale textural heterogeneity adds dramatically to the sound-wide benthic biological diversity.

Deflection of resilient materials for reduction of floor impact sound.

Science.gov (United States)

Lee, Jung-Yoon; Kim, Jong-Mun

2014-01-01

Recently, many residents living in apartment buildings in Korea have been bothered by noise coming from the houses above. In order to reduce noise pollution, communities are increasingly imposing bylaws, including the limitation of floor impact sound, minimum thickness of floors, and floor soundproofing solutions. This research effort focused specifically on the deflection of resilient materials in the floor sound insulation systems of apartment houses. The experimental program involved conducting twenty-seven material tests and ten sound insulation floating concrete floor specimens. Two main parameters were considered in the experimental investigation: the seven types of resilient materials and the location of the loading point. The structural behavior of sound insulation floor floating was predicted using the Winkler method. The experimental and analytical results indicated that the cracking strength of the floating concrete floor significantly increased with increasing the tangent modulus of resilient material. The deflection of the floating concrete floor loaded at the side of the specimen was much greater than that of the floating concrete floor loaded at the center of the specimen. The Winkler model considering the effect of modulus of resilient materials was able to accurately predict the cracking strength of the floating concrete floor.

Decontamination of polyvinylchloride- and rubber type flooring

International Nuclear Information System (INIS)

Kunze, S.

1975-01-01

These types, fabricated by mixing of the basic components, showed no relation between content of fillers and decontamination results. Decontamination results are partly poorer, if the flooring contains a high concentration of the filler, especially if the latter consists mainly of hydrophilic materials. The coloring of the floorings seems to have no influence on the decontamination but floorings with clearly separated patterns can not be recommended for nuclear facilities. Fabricated by chemical reactions between polymeres, vulcanization materials and fillers, the decontamination results depend definitely from the proper choice of the filler. Flooring types, containing lampblack, graphite, kaoline, barium sulfate and titanium oxide are easy to decontamine. Again, increasing contents of hydrophilic filler cause a fall off in the decontamination results. (orig.) [de

System and method of cylinder deactivation for optimal engine torque-speed map operation

Science.gov (United States)

Sujan, Vivek A; Frazier, Timothy R; Follen, Kenneth; Moon, Suk-Min

2014-11-11

This disclosure provides a system and method for determining cylinder deactivation in a vehicle engine to optimize fuel consumption while providing the desired or demanded power. In one aspect, data indicative of terrain variation is utilized in determining a vehicle target operating state. An optimal active cylinder distribution and corresponding fueling is determined from a recommendation from a supervisory agent monitoring the operating state of the vehicle of a subset of the total number of cylinders, and a determination as to which number of cylinders provides the optimal fuel consumption. Once the optimal cylinder number is determined, a transmission gear shift recommendation is provided in view of the determined active cylinder distribution and target operating state.

Vortex shedding from tandem cylinders

Science.gov (United States)

Alam, Md. Mahbub; Elhimer, Mehdi; Wang, Longjun; Jacono, David Lo; Wong, C. W.

2018-03-01

An experimental investigation is conducted on the flow around tandem cylinders for ranges of diameter ratio d/ D = 0.25-1.0, spacing ratio L/ d = 5.5-20, and Reynolds number Re = 0.8 × 104-2.42 × 104, where d and D are the diameters of the upstream and downstream cylinders, respectively, L is the distance from the upstream cylinder center to the forward stagnation point of the downstream one. The focus is given on examining the effects of d/ D, L/ d and Re on Strouhal number St, flow structures and fluid forces measured using hotwire, particle image velocimetry (PIV) and load cell measurement techniques, respectively. Changes in d/ D and L/ d in the ranges examined lead to five flow regimes, namely lock-in, intermittent lock-in, no lock-in, subharmonic lock-in and shear-layer reattachment regimes. Time-mean drag coefficient ( C D) and fluctuating drag and lift coefficients ({C^'D} and {C^'L}) are more sensitive to L/ d than d/ D. The scenario is opposite for St where d/ D is more prominent than L/ d to change the St. The detailed facet of the dependence on d/ D and L/ d of C D, {C^'D}, {C^'L} and St is discussed based on shear-layer velocity, approaching velocity, vortex formation length, and wake width.

Response of equipment in nuclear power plants to airplane crash

International Nuclear Information System (INIS)

Schalk, M.; Woelfel, H.

1975-01-01

The question has been posed concerning the effect of airplane crash on the safety of the equipment (pipes, vessels, etc.) mounted on the floors and walls inside the outer structure. This equipment is set into vibration by the crash-induced shaking of the outer building; the resulting stresses may be quite appreciable. The following questions arise: a) how large are these stresses. Can they, for example, be larger than the stresses produced by earthquake loading. b) What are the significant response parameters. c) Which methods of analysis and design criteria are reasonable. To what extent is it possible to apply the techniques which have become generally accepted for earthquake loading. The paper presents a preliminary answer to these questions pending further work in this area. (orig./HP) [de

Historical Cavern Floor Rise for All SPR Sites

Energy Technology Data Exchange (ETDEWEB)

Moriarty, Dylan Michael [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

2016-09-01

The Strategic Petroleum Reserve (SPR) contains the largest supply is the largest stockpile of government-owned emergency crude oil in the world. The oil is stored in multiple salt caverns spread over four sites in Louisiana and Texas. Cavern infrastructure near the bottom of the cavern can be damaged from vertical floor movement. This report presents a comprehensive history of floor movements in each cavern. Most of the cavern floor rise rates ranged from 0.5-3.5 ft/yr, however, there were several caverns with much higher rise rates. BH103, BM106, and BH105 had the three highest rise rates. Information from this report will be used to better predict future vertical floor movements and optimally place cavern infrastructure. The reasons for floor rise are not entirely understood and should be investigated.

Faraday effect in hollow quantum cylinder of finite thickness

International Nuclear Information System (INIS)

Ismailov, T.G.; Jabrailova, G.G.

2009-01-01

The interband Faraday rotation in hollow quantum cylinder of finite thickness is theoretically investigated. Faraday rotation in the dependence on incident light energy for different values of cylinder thickness. It is seen that the resonance peaks appear on Faraday rotation curve. The roles of selection are obtained

Association between preterm labour and pelvic floor muscle function.

Science.gov (United States)

Aran, Turhan; Pekgöz, Ipek; Bozkaya, Hasan; Osmanagaoglu, Mehmet A

2018-03-23

We hypothesised that the pressure on the cervix increases with advancing gestation and it may lead to a cervical shortening and cause preterm labour in women with weak pelvic floor muscles. The aim of this prospective study was to measure vaginal resting pressure and pelvic floor muscle strength in the first trimester of pregnancy and to investigate their effects on labour. A study was conducted on the pregnant women with a low risk for preterm birth. The pelvic floor muscle strength and vaginal resting pressure were assessed in 320 pregnant women at their first trimester with a vaginal pressure measurement device. Fifty-two pregnant women were hospitalised for tocolytic therapy because of spontaneous preterm labour. Thirty-two of them (10.2%) had a preterm delivery despite the tocolytic therapy. Both the vaginal resting pressure (p = .009, 95%CI: 0.8; 5.9) and the pelvic floor muscle strength (p = .01, 95%CI: 3.5; 13.1) were significantly lower in the women with a preterm labour. Impact statement What is already known on this subject? The pelvic floor muscles have an essential role in continence and provide support to the pelvic organs. They also have an impact on labour. The pelvic floor muscles should distend to allow the passage of the foetus during labour. The rotation and flexion of the foetal head is due to the pelvic floor resistance. The effect of a vaginal birth on the pelvic floor's function is readily understood. On the other hand, the effect of the pelvic floor muscle function on labour is still controversial. What do the results of this study add? This prospective study showed that there is a negative association between the pelvic floor muscle strength and preterm labour. This is the first clinical study indicating that weak pelvic floor muscles may cause a preterm labour. What are the implications of these findings for clinical practice and/or further research? Pelvic floor physical therapy may be an alternative preventive strategy to reduce

A marine dynamic penetrometer for the determination of sea floor geotechnical properties

Science.gov (United States)

Stephan, S.; Kaul, N. E.; Villinger, H. W.

2013-12-01

We present a seafloor lance penetration monitoring system: the Lance Insertion Retardation Meter (LIRmeter). The device can be used to infer geotechnical seafloor properties, such as bearing capacity by monitoring the deceleration of a free-fall penetrating lance. The deceleration record can be furthermore used to estimate mean grain size and mud content of the sea floor as well as total penetration depth. The LIRmeter is contained in a pressure vessel (440 x 110 mm) and equipped with accelerometers of different sensitivities to (i) determine sea floor resistance during penetration and (ii) to generate a depth axis. Typically, measurements are carried out in a pogo style fashion to allow a rapid measurement progress during field campaigns. The LIRmeter is intended to determine sea floor properties on the sole basis of deceleration measurements in order to achieve a mechanically and electronically robust system. Data is sampled at a resolution of 16 bit and at a rate of typically 500 Hz for each channel. The device can either be installed in any type of lance i.e. marine heat flow probes, gravity corers, piston corers or can be used in combination with a purpose built lance as a standalone instrument. It has a usable length of four meters, a total weight of 280 kg in air and can be operated up to full ocean depth (6000m). The bearing capacity of the sea floor is a critical factor for marine engineering projects such as burial of marine cables, pipeline laying and foundations. Knowledge of the mud content can provide constraints for the estimation of hydraulic conductivity. The identification of weak zones along a slope can moreover provide vital information for risk assessment studies. Traditionally, frame based, quasi static Cone Penetration Tests (CPT) or sampling methods like gravity coring are used to conduct these types of investigation. In comparison to established but time consuming and rather costly methods, the LIRmeter is intended (i) for near surface

Infinitely long cylinder in a sinusoidal field (Problem 2)

International Nuclear Information System (INIS)

Ida, N.

1986-01-01

The results presented here were obtained with a 2-D (and axisymmetric) eddy current program called EDDYNDT. The program uses the magnetic vector potential formulation and was specifically designed for the calculation of coil impedances in NDT applications. For normal applications, flux densities, forces, eddy current densities and stored and dissipated energies are not calculated. The program required minor modifications to calculated these quantities form the magnetic vector potential. In its present form, program EDDYNDT cannot handle flux normal boundary conditions. To avoid this, half the cylinder was modeled as opposed to the quarter cylinder in the mesh recommended in the problem outline. This increased the number of elements and nodes but did not change their density or location. Both a solution without the cylinder and a solution with the cylinder are presented. The fields presented are calculated at the center of each element. For this reason, the values presented are interpolated between neighboring elements. This creates a problem, particularly at discontinuities where the errors are largest

Rolling Cylinder Phase 1

DEFF Research Database (Denmark)

Margheritini, Lucia; Taraborrelli, Valeria Taraborrelli

Margheritini and Valeria Taraborrelli(valeria.taraborrelli@hotmail.it) with a total of 3 day visit from the developers. Laboratory tests in irregular waves will be performed by Lucia Margheritini. The report is aimed at the first stage testing of the Rolling Cylinder wave energy device. This phase includes...

Response of equipment in nuclear power plants to airplane crash

International Nuclear Information System (INIS)

Schalk, M.; Woelfel, H.

1976-01-01

Nuclear power plants in Germany are to be designed against airplane crash. Two problems arise: first, the local problem of penetration as well as local destruction of the building and secondly the airplane induced vibrations of the whole building which cause loadings for secondary systems (equipment). This paper deals especially with the second problem. Floor response spectra due to airplane crash are presented for two different power plant buildings. The influence of various parameters (time history of excitation, direction and location of impact, mathematical model, soil, damping, etc.) are discussed. A comparison with the results of earthquake loading is given. Suggestions are made for developing suitable floor design spectra and using them to analyse multidegree-of-freedom systems. However, the paper gives only a partial answer to the questions arising because of some important restrictions which had to be made. Studies concerning these restrictions are still being conducted and will be presented in a separate paper. (Auth.)

Biomechanics of the pelvic floor musculature

NARCIS (Netherlands)

Janda, S.

2006-01-01

The present thesis was motivated by two main goals. The first research goal of the thesis was to understand the complex biomechanical behaviour of the pelvic floor muscles. The second goal was to study the mechanism of the pelvic organ prolapse (genital prolapse). The pelvic floor in humans is a

Electrostatics of spherical metallic particles in cylinder electrostatic separators/sizers

International Nuclear Information System (INIS)

Lu Hongzhou; Li Jia; Guo Jie; Xu Zhenming

2006-01-01

This paper presents a theoretical analysis of the dynamics of spherical metallic particles in electrostatic separators/sizers (ESSs). A computational algorithm is employed to depict the cylinder-type electrode arrangements applied in some electrostatic processes generating non-uniform electric fields. The ESS consists of a pair of conducting cylinders. The upper cylinder is energized by HVdc, while the lower one is grounded and mounted horizontally on a revolvable axis. The aim of this paper is to present a new electrode configuration and demonstrate the usefulness of numerical techniques for the evaluation of the particle's motion. A computer program was employed for analysing the behavior of spherical particles in a two-dimensional electrode arrangement that models the actual electric field configuration of cylinder-type electrostatic separators/sizers. The analysis is needed for the development of any new application of this cylinder-type electrode arrangement as an electrostatic separation method. The results reveal that the particle's motion depends on its radius and density and amplitude of the applied voltage. The actual granular mixtures with different specific mass and radius could be separated applying this cylinder-type electrostatic separation method; the lift voltage is an important parameter for separation. With a program for two-dimensional analysis of the electric field, the computational procedure presented in this paper could be employed for any particle shapes

Bubbly flows around a two-dimensional circular cylinder

Science.gov (United States)

Lee, Jubeom; Park, Hyungmin

2016-11-01

Two-phase cross flows around a bluff body occur in many thermal-fluid systems like steam generators, heat exchangers and nuclear reactors. However, our current knowledge on the interactions among bubbles, bubble-induced flows and the bluff body are limited. In the present study, the gas-liquid bubbly flows around a solid circular cylinder are experimentally investigated while varying the mean void fraction from 5 to 27%. The surrounding liquid (water) is initially static and the liquid flow is only induced by the air bubbles. For the measurements, we use the high-speed two-phase particle image velocimetry techniques. First, depending on the mean void fraction, two regimes are classified with different preferential concentration of bubbles in the cylinder wake, which are explained in terms of hydrodynamic force balances acting on rising bubbles. Second, the differences between the two-phase and single-phase flows (while matching their Reynolds numbers) around a circular cylinder will be discussed in relation to effects of bubble dynamics and the bubble-induced turbulence on the cylinder wake. Supported by a Grant (MPSS-CG-2016-02) through the Disaster and Safety Management Institute funded by Ministry of Public Safety and Security of Korean government.

Case Report: Facial and eye injury following a fridge cylinder gas explosion

Directory of Open Access Journals (Sweden)

Monsudi Kehinde Fasasi

2017-11-01

Full Text Available Fridge cylinders contain liquefied petroleum gas (LPG, an inflammable gas of mixture of propane and butane [1]. It’s colourless but odourised to give warning during leakage. Injury from accidental fridge cylinder explosion is similar to any other blast injuries in terms of the release of hot gases, blast wave and metal fragments resulting in extensive skin burns, abrasions, penetrating injury and tissue loss [2-4]. Ocular trauma following gas cylinder explosion is rare however, Babar et al reported 20% of ocular trauma to be secondary to gas cylinder and battery explosion [2]. To our knowledge, this is the first case of facial and eye injury following a fridge cylinder gas explosion reported in the literature.

Large eight.cylinder Stirling engine for biofuels

DEFF Research Database (Denmark)

Carlsen, Henrik; Biedermann, F.; Bovin, Jonas Kabell

2003-01-01

A large Stirling engine with an electric power output of 70 kW has been developed for small-scale CHP using wood chips and other sorts of biomass as fuel. The development of the engine is based on the results from the development of a four-cylinder Stirling engine with a power output of 35 k...... in the hot end connecting the expansion space with the hot end of the regenerator through the heater panel. However, this has resulted in comparably large dead volumes and flow losses in the connections between the heater and the regenerator/expansion volume. For the new eight-cylinder engine the design...... of the connections between the heater and the regenerator/expansion volume have been improved considerably, reducing the flow losses and internal dead volume. Results from simulations indicate an improvement of power output and efficiency of about 10%. A four cylinder double acting Stirling engine is basically...

Composite materials research and education program: The NASA-Virginia Tech composites program

Science.gov (United States)

Herakovich, C. T.

1980-01-01

Major areas of study include: (1) edge effects in finite width laminated composites subjected to mechanical, thermal and hygroscopic loading with temperature dependent material properties and the influence of edge effects on the initiation of failure; (2) shear and compression testing of composite materials at room and elevated temperatures; (3) optical techniques for precise measurement of coefficients of thermal expansion of composites; (4) models for the nonlinear behavior of composites including material nonlinearity and damage accumulation and verification of the models under biaxial loading; (5) compressive failure of graphite/epoxy plates with circular holes and the buckling of composite cylinders under combined compression and torsion; (6) nonlinear mechanical properties of borsic/aluminum, graphite/polyimide and boron/aluminum; (7) the strength characteristics of spliced sandwich panels; and (8) curved graphite/epoxy panels subjected to internal pressure.

Motor cortical representation of the pelvic floor muscles.