4681   Study on the interior noise-reduction of a passenger car Study on the interior noise-reduction of a passenger car    1991 This study predicts the interior noise of a passenger car under broad-band excitation and established its reduction scheme using coupling coefficients which represent the mode coupling between the structural vibration modes and the acoustic modes. The structural modes and the acoustic modes are determined for the structural-acoustic coupling analysis. Modal testing for the structural modes is performed on a passenger car. Acoustic modes of the interior cavity is calculated by finite element anal... 查看全文

4682   Regional upscaling: A new method to upscale waterflooding in heterogeneous reservoirs for a range of capillary and gravity effects Regional upscaling: A new method to upscale waterflooding in heterogeneous reservoirs for a range of capillary and gravity effects    2001 This paper presents a new, two-phase upscaling methodology here-after referred to as "regional" upscaling. A fine-grid flow simulation is performed on a representative section of the reservoir. Dimensionless numbers are then calculated for each fine-grid cell to determine the dominant flow regime in that cell. The coarse grid is selected based upon the spatial locations of the different force regimes observed in the fine-grid simulation model. Two-phase upscaling is then performed from the fine ... 查看全文

4683   System for collapse and reliability analysis of ship structures using a spatial plate element model System for collapse and reliability analysis of ship structures using a spatial plate element model    1993 This paper is concerned with the ultimate strength and reliability analysis of ship's hull girders, which are composed of the spatial membrane elements and subjected to combined static loads and extreme wave loads. At first, a new method is proposed for generating safety margins of general plate structures. The linearized failure condition of an element is introduced, which takes account of the yielding and buckling collapse under the plane stress condition. The failure criterion facilitates the... 查看全文

4684   VERY SIMPLE METHOD FOR ESTIMATING TEMPERATURE IN FIRE EXPOSED CONCRETE STRUCTURES. VERY SIMPLE METHOD FOR ESTIMATING TEMPERATURE IN FIRE EXPOSED CONCRETE STRUCTURES.    1986 A set of very handy formula and diagrams have been derived for calculating temperature in fire exposed concrete structures. Fire conditions according to the ISO 834 standard fire as well as natural fires may be assumed, and the influence of various material properties may be considered in a simple way. The method is particularly easy to use when the ISO 834 standard fire and normal concrete properties are assumed. The load bearing capacity of a concrete element in a fire decreases as the strengt... 查看全文

4685   On construction of high order exponentially fitted methods based on parameterized rational approximations to exp(q) On construction of high order exponentially fitted methods based on parameterized rational approximations to exp(q)    1999 By the discussion of the formula and properties of (4,4) parametric form. rational approximated to function exp(q), the fourth order derivative one-step exponentially fitted method and the third order derivative hybrid one-step exponentially fitted method were presented, their order p is between 6 and 8. The necessary and sufficient conditions for the two methods to be A-stable were given. Finally, for the fourth order derivative method, the error bound and the necessary and sufficient condition... 查看全文

4686   IDENTIFYING THE STRUCTURE MODAL PARAMETERS BY USING OPTIMIZED-ITERATION METHOD FOR THE PRIMARY VALUE. IDENTIFYING THE STRUCTURE MODAL PARAMETERS BY USING OPTIMIZED-ITERATION METHOD FOR THE PRIMARY VALUE.    1984 The correlation between the structure response and modal parameters is based on the modal superposition theorem by which a simple and efficient program for calculating the modal parameters could be written. A method for optimizing the primary value has been developed and its principle as well as its algorithm are discussed in this paper. The optimization of the primary values is done under the condition that the total variance is assured to be minimum. In so doing, the problem of the divergency ... 查看全文

4687   A solution of the neutron diffusion equation for a hemisphere containing a uniform. source A solution of the neutron diffusion equation for a hemisphere containing a uniform. source    2004 An analytic solution of the diffusion equation for a hemisphere of fissile or non-fissile material is presented which contains a spatially uniform. neutron source. Numerical results are given for the flux distribution for one-speed fast neutrons in 235U and also for a non-fissile element of similar scattering properties. We use these results to check the accuracy of the finite element code EVENT. The procedure is also developed for multigroup calculations. In an Appendix we outline the procedure... 查看全文

4688   Real-time aberration correction using phase diversity on the IBM SP2 parallel computer Real-time aberration correction using phase diversity on the IBM SP2 parallel computer    1996 Optical aberrations are characterized by orthogonal basis functions composed of discretized Zernike polynomials. The coefficients associated with each Zernike polynomial can be measured using a phase diversity wave front sensing technique. Nonlinear optimization techniques are utilized to calculate the Zernike coefficients in a serial manner. Even though this traditional method is attractive, it is computationally a very formidable task to calculate several Zernike coefficients for a given syste... 查看全文

4689   High-dose cyclophosphamide for mobilization of circulating stem cells in chronic myeloid leukemia High-dose cyclophosphamide for mobilization of circulating stem cells in chronic myeloid leukemia Charles Russell Bardeen    2009 Abstract: Experimental and clinical data suggest that Ph-negative myeloid progenitor cells are present, albeit suppressed, in the bone marrow of chronic myeloid leukemia (CML) patients. These residual Ph-negative cells might, in certain circumstances, regain their proliferative advantage over the leukemic Ph-positive clone. Treating CML patients with intensive chemotherapy might allow the harvest, in the early phase of recovery, of Ph-negative stem cells to be used as graft after myeloablative ... 查看全文

4690   DYNAMIC RESPONSE OF A TURBO-GENERATOR SET. DYNAMIC RESPONSE OF A TURBO-GENERATOR SET.    1985 A computational model of a turbo-generator set has been developed using finite element discretization. A Timoshenko beam element is used to model the axisymmetric shaft allowing for tapered sections and lumping the wheel masses at internal points. The rotor dynamic matrix is grounded by the speed dependent bearing stiffness and damping forces. A modal reduction procedure is employed to reduce the degrees of freedom so that computations may be carried out on a micro-computer. The model is used to... 查看全文

4691   Direct-search method for the computer design of holograms Direct-search method for the computer design of holograms    1996 A direct-search method for the computer design of phase holograms is presented. This general method is based upon making a succession of small changes to the hologram phase distribution under the control of a cost function. It is not restricted to any particular optical geometry. The effect upon the image is calculated using an approximation to the Kirchhoff integral. The factors affecting the algorithm and cost function, both in terms of the quality of the solution and the computing efficiency,... 查看全文

4692   Force distribution and power transmission over a rectangular contact area subject to a uniform. velocity excitation Force distribution and power transmission over a rectangular contact area subject to a uniform. velocity excitation    2002 The force distribution and power transmission over a rectangular contact area of an infinite plate subjected to a uniform. velocity excitation were investigated. The method of calculate the force caused by uniform. velocity was derived by means of a discrete model and the distribution of the forces over a contact area was calculated. The power transmission at every point within the contact area and the total power transmission of the whole contact area were investigated under effects of the dime... 查看全文

4693   A detailed quantum mechanical and quasiclassical trajectory study on the dynamics of the H++H2&rarrH2+H+ exchange reaction A detailed quantum mechanical and quasiclassical trajectory study on the dynamics of the H++H2&rarrH2+H+ exchange reaction    2006 The H++H2 exchange reaction has been studied theoretically by means of a different variety of methods as an exact time independent quantum mechanical, approximate quantum wave packet, statistical quantum, and quasiclassical trajectory approaches. Total and state-to-state reaction probabilities in terms of the collision energy for different values of the total angular momentum obtained with these methods are compared. The dynamics of the reaction is extensively studied at the collision energy of ... 查看全文

4694   Application of finite element method to acoustic scattering problems Application of finite element method to acoustic scattering problems    1996 For aircraft, scattering of engine and rotor noise from the fuselage and wings can considerably influence community and interior noise levels. Here the finite element method (FEM) is considered as a modeling technique because of its ability to solve for a broad range of governing equations and its potential efficiency advantages over the more commonly used boundary element method. With FEM, however, the data storage requirements become very demanding for three-dimensional problems involving real... 查看全文

4695   Influence of different ground covers on the heating potential of earth-to-air heat exchangers Influence of different ground covers on the heating potential of earth-to-air heat exchangers    1996 Ten years' hourly measurements of air and ground temperature values at various depths below bare and short grass soil at Dublin Airport have been used in order to investigate the impact of different ground surface boundary conditions on the efficiency of a single and a multiple parallel earth-to-air heat exchanger system. The heating potential of both these systems buried under bare soil has been assessed and compared with the heating potential of the same systems buried under short-grass-covere... 查看全文

4696   Method on unstructured grid for incompressible flows Method on unstructured grid for incompressible flows    2005 A method for solving steady incompressible Navier-Stokes equations on hybrid unstructured grids was presented. The pressure correction method, originally developed by Date for flow on structured grids, was employed to enforce mass conservation on hybrid unstructured grids. All the variables were defined at the center of each cell while the face velocities were calculated by interpolation at the mid-points of the corresponding cell faces. The convection flux was calculated with upwind least-squar... 查看全文

4697   Synchronization of active filter current reference to the network Synchronization of active filter current reference to the network    2002 An improved method to determine active filter current reference is presented. A new principle of synchronization is proposed. The common synchronization is based on net voltage zero-crossing detection. Since it is very sensitive to disturbances especially at the values close to zero, false synchronization pulses can be generated. The proposed method measures net voltage and load current, and calculates net voltage fundamental component on line. As a result, the whole reactive power can be compen... 查看全文

4698   Prevalence of and risk factors for abnormal ankle–brachial index in patients with type 2 diabetes Prevalence of and risk factors for abnormal ankle–brachial index in patients with type 2 diabetes    2012 Background: The aim of the present study was to examine abnormalities in the ankle–brachial index (ABI) and related risk factors in patients with type 2 diabetes. 查看全文

4699   Stresses and deformations due to flow past a circular cylinder Stresses and deformations due to flow past a circular cylinder    1995 An analysis has been presented to calculate the stresses and deformations in the cylinder due to flow past a stationary circular cylinder by adopting a numerical technique. The flow has been considered at Reynold's number 3.32 × 105 and the cylinder has been considered to be a thick cylinder under plane strain loading conditions. The pressure distribution on the cylinder surface has been approximated by Fourier series. The solution has been obtained by using Airy's stress function approach... 查看全文

4700   Different incidences of epigenetic but not genetic abnormalities between Wilms tumors in Japanese and Caucasian children Different incidences of epigenetic but not genetic abnormalities between Wilms tumors in Japanese and Caucasian children    2012 Epidemiological studies show that the incidence of Wilms tumor (WT) in East-Asian children is half of that in Caucasian children. Abnormalities of WT1,CTNNB1,WTX, and IGF2 were reported to be involved in Wilms tumorigenesis in Caucasians, although none of the studies simultaneously evaluated the four genes. WTX forms the β-catenin degradation complex; however, the relationship between WTX abnormality and CTNNB1 mutation was uncertain in WTs. We examined abnormalities of the four genes in 11... 查看全文

4701   Discussion on the resistance property of natural ventilation induced by wind force Discussion on the resistance property of natural ventilation induced by wind force    2004 Through the discussion of the resistance properties of natural ventilation induced by wind force, a method of local pressure loss superposition was proposed to calculate the pressure loss. Airflow through buildings is composed of the sudden contraction section and the sudden expansion section. From this, it can be concluded that the discharge coefficients of the inlet opening and the outlet opening are different. A simple method to estimate the flow rate through buildings with large openings was... 查看全文

4702   PREDICTION OF THE EFFICIENCY OF NON-CIRCULAR SPUR GEARS. PREDICTION OF THE EFFICIENCY OF NON-CIRCULAR SPUR GEARS.    1984 This paper reports predictions and test results which indicate the average loss rate per revolution for non-circular gears can be considered essentially the same as those for circular gears given similar specifications and operating conditions. There is, however, a significant variation in loss rate with respect to non-circular gear angular position. The method of prediction was extended from a procedure developed by Anderson and Loewenthal for calculating the losses of external spur gears. The ... 查看全文

4703   PREDICTION OF VOLTAGE DISTORTION FACTOR DUE TO THE CONVERTER HARMONICS IN AN 11 Kv SYSTEM. PREDICTION OF VOLTAGE DISTORTION FACTOR DUE TO THE CONVERTER HARMONICS IN AN 11 Kv SYSTEM.    1986 Converters distort network voltage and have detrimental effects on the supply system. The existing analytical methods are not feasible to calculate the voltage distortion of discrete networks. In order to facilitate the procedure a method for the computation of the voltage distortion factor by digital computer simulation of networks is developed. Computed results and experimentally obtained values are compared and a good correlation is found. 查看全文

4704   Method to exclude preconsolidation deformation in finite element calculation of soil engineering Method to exclude preconsolidation deformation in finite element calculation of soil engineering    2004 The gravity induced preconsolidation deformation of rock and soil has been finished before our consideration in many geotechnical problems. The stress field in soil mass is balanced with the gravity field. So in the FEM calculation that is based on the initial condition above, if the gravity is loaded directly, a rather big deformation will occur which should have been finished. So on the basis of initial stress load theory that is studied, an approach is proposed to exclude the preconsolidation... 查看全文

4705   Estimation method of firing accuracy for area targets based on Monte Carlo integral method Estimation method of firing accuracy for area targets based on Monte Carlo integral method    2009 Firing accuracy is one of the primary performance indexes for the missile weapon system. This paper proposes a method for estimating firing accuracy at the area target. Specifically, the hit area circular error probability (ACEP) is defined as an accuracy index for the area target and further a Monte Carlo integral method is designed for calculating ACEP. Theoretical analysis and simulation results show that the definition of firing accuracy is reasonable and the calculating method is simple and... 查看全文

4706   OPTIMIZATION OF MASS AND STIFFNESS MATRICES USING A GENERALIZED INVERSE TECHNIQUE ON THE MEASURED MODES. OPTIMIZATION OF MASS AND STIFFNESS MATRICES USING A GENERALIZED INVERSE TECHNIQUE ON THE MEASURED MODES.    1985 A method, based on the theory of a generalized inverse of the measured modal matrix, is used to improve the mass and stiffness matrices of a finite element model. The method, using the measured normal modes and frequencies, directly calculates a set of minimum changes in the physical matrices which constrains the resulting mass and stiffness matrices to produce an equivalent eigen-solution. The technique produces insight into the character of the measured modal information such that a sensitivit... 查看全文

4707   Design optimization using the boundary element method Design optimization using the boundary element method    1991 Structural optimization is often confined to sizing simple design variables, such as plate thicknesses and bar cross-sectional areas, while the geometric shapes of components remain largely unchanged. Shape optimization is more complex, changing the shape of the boundary, subject to appropriate constraints. The boundary element method, being a boundary-oriented technique is very appropriate for this purpose. It can overcome a number of the difficulties associated with its main rival, the finite ... 查看全文

4708   Characterization of the interactions in the poly(4-hydroxystyrene)/poly(Ε-caprolactone) system by inverse gas chromatography Characterization of the interactions in the poly(4-hydroxystyrene)/poly(Ε-caprolactone) system by inverse gas chromatography    1995 Inverse gas chromatography has been used to measure the thermodynamic interaction between poly(4-hydroxystyrene) (P4HS) and poly(Ε-caprolactone) (PCL) at 190°C. The retention behaviour of the homopolymers and three blends (0.25, 0.5 and 0.75 P4HS volume fraction) was characterized for 13 probes. The polymer-polymer interaction parameter χ23 calculated from the Scott-Flory-Huggins formalism showed an apparent dependence on the probes. The method based on the equation-of-state theo... 查看全文

4709   Characterization of creep behavior. of polymer composites by the use of dynamic test methods Characterization of creep behavior. of polymer composites by the use of dynamic test methods    1995 This paper describes a new dynamic test method for estimating momentary creep response of polymers and their composites. It is based on impulsive excitation of test specimens and the subsequent measurement of their frequency response functions. The vibration test involves the determination of frequency dependent storage modulus and loss factors. The Time-Temperature Superposition (TTS) principle is applied to the frequency domain vibration test data to form. a master curve, which is then transfo... 查看全文

4710   RAPD analysis of genetic variability among Stylosanthes guianenesis accessions of resistant and susceptible to the stylo anthracnose RAPD analysis of genetic variability among Stylosanthes guianenesis accessions of resistant and susceptible to the stylo anthracnose    2005 Stylosanthes guianenesis Sw. is an important tropical forage legume grown and utilized in the tropics and the subtropics of South China. Anthracnose, caused by Colletotrichum gloeosporioides (Penz.) Sacc., is a major constraint to the extensive use of Stylosanthes. Forty-five accessions of S. guianensis were assessed with RAPD for genetic diversity and for resistance to anthracnose. RAPD analysis was performed using twenty primers screened from 200 arbitrary oligonucleotides, and a 71.5% level o... 查看全文

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