Journal articles: 'Nite element method'

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Öchsner, Andreas. "On some Conceptual Considerations for the Finite Element Simulation of the Oxygen Out-Diffusion in Ag-MgO Composites." Defect and Diffusion Forum 283-286 (March 2009): 1–5. http://dx.doi.org/10.4028/www.scientific.net/ddf.283-286.1.

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The presence of atomic oxygen at internal metal-ceramic oxide interfaces signi¯- cantly affects the physical properties of the interfaces which in turn affects the bulk properties of the material. The application of numerical tools such as the ¯nite element method requires some conceptional considerations if results from different finite element meshes of methods should be comparable. This paper summarises some of these thoughts in order to provide the right basis for comparative investigations.

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PROKOPOVICH, Anatoly A., and Yana A. BUZOVSKAYA. "MODELING OF STRESS-DEFORMED STATE OF BENDED REINFORCED CONCRETE ELEMENTS IN ZONES OF CLEAN AND TRANSVERSE BEND." Urban construction and architecture 11, no. 1 (December 15, 2021): 26–33. http://dx.doi.org/10.17673/vestnik.2021.01.3.

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The article deals with the analysis of the stress-strain state (SSS) of a bent reinforced concrete element in zones of pure and transverse bending. It is assumed that a bent element in the process of loading (after the formation of normal and oblique cracks) is divided into blocks, united by uncracked concrete and reinforcement that has adhesion to concrete. SSS was formed using the results of experimental studies of special prototypes in the PC “Lira-SAPR”. A fi nite element model of a prototype has been developed in the form of a reinforced concrete rectangular beam loaded with two identical concentrated forces in the span. By the method of successive approximations, the process of formation and formation of a system of cracks is realized, with which the beam is divided into blocks during loading. The results of calculating the fi nite element model and their comparison with experimental data are presented.

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Dyachenko, Denis Yu, and Svetlana V. Dyachenko. "Finite element method in computer simulation for improved patient care in dentistry: A systematic review." Kuban Scientific Medical Bulletin 28, no. 5 (October 30, 2021): 98–116. http://dx.doi.org/10.25207/1608-6228-2021-28-5-98-116.

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Background. The fi nite element method is gaining acknowledgment in Russia and other developed countries in a range of areas, including medicine. In stomatology, the method is applicable in research and implication of novel treatment and relevant material design.Objective. The review highlights usage of the fi nite element method in computer simulation to improve quality of patient dental care.Methods. The review analyses the state-of-the-art in current scientific literature. Records were mined in the PubMed and e-Library databases at a depth of 10 years, with selective inclusion of earlier articles. The query keywords were: finite element method [метод конечных элементов], computer simulation [компьютерная симуляция], quality of life improvement [повышение качества жизни], oral diseases [заболевания полости рта], dental treatment [стоматологическое лечение].Results. The review systematically surveys 56 scientific papers in the focus area for current state-of-the-art in the finite element analysis-empowered simulation in dentistry. The method’s rising employment is conditioned by its flexibility, 3D-object modelling simplicity and the rapid acquisition of reliable high-quality output. Its undoubted paramount advantage in dentistry is an explicit software visualisation of reliable results through co-modelling of multiple oral parameters.Conclusion. The growing acquaintance, mastering and use of this technique among researchers around the globe will give impetus to novel diagnosis and treatment, as well as relevant management algorithms in particular patient categories to enable personalisation of even mass dental check-up. This will reduce the number of visits, peri- and posttreatment error and complication rates for the improved patient’s quality of life and social rehabilitation.

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Das, S., M. F. Abbod, Q. Zhu, Eric J. Palmiere, I. C. Howard, D. A. Linkens, and C. M. Sellars. "A Hybrid Modelling Approach Applied to the Evolution of Microstructure during Plane Strain Deformation." Materials Science Forum 715-716 (April 2012): 416–26. http://dx.doi.org/10.4028/www.scientific.net/msf.715-716.416.

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This paper presents a modelling strategy that combines neuro-fuzzy methods to dene the material model with cellular automata representations of the microstructure, all embedded within a nite element solver that can deal with the large deformations of metal processing technology. We use the acronymnf-CAFE as a label for the method. The need for such an approach arises from the twin demands of computational speed for quick solutions for ecient material characterisation by incorporating metallurgical knowledge for material design models and subsequent process control. In this strategy, the cellular automata hold the microstructural features in terms of sub-grain size and dislocation density which are modelled by a neuro-fuzzy system that predicts the ow stress. The proposed methodology is validated on a two dimensional (2D) plane strain compression nite element simulation with Al1%Mg alloy. Results from the simulations show the potential of the model for incorporating the eects of the underlying microstructure on the evolving ow stress elds. In doing this, the paper highlights the importance of understanding the local transition rules that aect the global behaviour during deformation.

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Manchorova-Veleva, Neshka А. "Three-dimensional analysis of cavity wall deformation after composite restoration of masticatory teeth." Folia Medica 53, no. 4 (December 1, 2011): 53–59. http://dx.doi.org/10.2478/v10153-011-0068-8.

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ABSTRACT AIM: The aim of the present work was to study the size of cavity wall deformation in eight class I and II defects after composite restoration. MATERIALS AND METHODS: 1. Creating a geometric model - data on the size of the left maxillary second premolar were obtained from a routine craniofacial scanning of a 20-yearold patient with a 2,5 Dental CT scanner (General Electric), with high resolution and 0.625mm-thin slices. The contour of each of the 33 cross-sections of tooth 25 was delineated using graphics software (CorelDraw 7.0) and transferred to a specialized product for engineering design (SolidWorks Offi ce Premium 2010, SolidWorks Corp. USA). The pulp cavity and periodontal ligament were created in the same manner and were integrated in the premolar body; 2. Generation of a fi nite element method - the geometric model was exported to specialized software for analysis by the fi nite element method - COSMOSWorks 2010, which automatically builds a 3D fi nite elements mesh. Based on the generated model, eight additional models of class I and II cavities with different geometries, adhesive layer and nanofi lled composite restorations were constructed. The polymerization shrinkage was modelled by thermal deformation, with a negative temperature difference (cooling), corresponding to the actual volume shrinkage of the composite materials by 2.1%. RESULTS: In models A and B, the maximum cavity wall displacement was small - 0.014 mm and 0.015 mm, respectively. In models A1, B1, C1 and C, the displacement was at the expense of large deformation of the dental tissues. The maximum cavity wall displacements were 0.020 mm, 0.026 mm, 0.020 mm, 0.035 mm, respectively. The least cavity wall displacement was in models A2 and B2 with 0.008 mm and 0.017 mm, respectively. CONCLUSIONS: The least displacement resulting from cavity wall deformation is found in patient-friendly class I and II preparations. Preservation of the dental tissues reduces the risk of mechanical pressure on the dentinal lymph and the likelihood of post-operative sensitivity.

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Zhou, Jing, Bao Yu Wang, Lei Fu, and Qing Lei Meng. "A Method to Optimize Aluminum Alloy Door Impact Beam Stamping Process Using NSGA-II." Materials Science Forum 773-774 (November 2013): 89–94. http://dx.doi.org/10.4028/www.scientific.net/msf.773-774.89.

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The process parameters of aluminium alloy hot stamping produce an importantly effect on production forming quality. In the case of a door impact beam inside the car doors, the fi-nite-element model of aluminium alloy hot stamping is set up. Based on the model, the forming quality is investigated under usual process condition. Using the Latin hypercube method, we sampled the data points from design space of process parameters. Data points are imported into finite-element model to calculate the forming quality indices. According to their responding values, the quadratic response surfaces between process parameter inputs and forming quality indices are initialized. By optimized the response of the process parameters exercising multi-objective genetic algorithm—NSGA-II (non-dominated sorting genetic algorithm), the Pareto combinations of blank hold force and stamping velocity are obtained. Finally, by comparison with the results of stamping trial and numerical simula-tion, it is concluded that the finite-element model can be used to predict forming defects and is consistent with actual condition. Thus the optimization method is feasible.

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Djaghout, Manal, Aberrazak Chaoui, and Khaled Zennir. "Full discretization to an hyperbolic equation with nonlocal coefficient." Boletim da Sociedade Paranaense de Matemática 40 (January 23, 2022): 1–14. http://dx.doi.org/10.5269/bspm.46032.

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We present full discretization of the telegraph equation with nonlocal coeffecient using Rothe-nite element method. For solving the equation numerically we use the Newton Raphson method, but the nonlocal term causes diffeculties because the Jacobien matrix is full. To remedy these diffeculties we apply the technique used by Sudhakar [4]. The optimal a priori error estimates for both semi discrete and fully discrete schemes are derived in V and H1 and a numerical experiment is described to support our theoretical result.

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Kovalev, Alexei A., and Dmitry S. Panych. "Modeling of thermal processes in a contact wire by the fi nite element method using Comsol Multiphysics 5.2 software package." Innotrans, no. 3 (2017): 49–52. http://dx.doi.org/10.20291/2311-164x-2017-3-49-52.

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Izudin Kapetanović, Nermin Sarajlić, Majda Tešanović, and Mensur Kasumović. "NUMERICAL SOLUTION FOR THE DISTRIBUTION OF THE ELECTROMAGNETIC AND THERMAL FIELDS OF AN AIR-CORE TRANSFORMER." Journal of Energy - Energija 57, no. 4 (October 11, 2022): 424–39. http://dx.doi.org/10.37798/2008574331.

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The article presents a numerical solution for the distribution of the electromagnetic and thermal fi elds of an air-core transformer using the fi nite element method. The distribution of the magnetic fi eld is determined for the dynamic steady state and magnetic nonlinear core characteristics. The model presented facilitates the establishment of criteria for optimizing transformer operation under various load conditions, environments as well as in the case of failures. Thus, the transformer can operate at maximum capacity while, at the same time, the probability of faults due to overheating is reduced to a minimum.

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10

Gong, Dian Xuan, and Feng Gong Lang. "On the Dimension of Bivariate C¹ Cubic Spline Space with Homogeneous Boundary Conditions over a CT Triangulation." Applied Mechanics and Materials 50-51 (February 2011): 488–92. http://dx.doi.org/10.4028/www.scientific.net/amm.50-51.488.

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A bivariate spline is a piecewise polynomial with some smoothness de ned on a parti- tion. In this paper, we mainly study the dimensions of bivariate C1 cubic spline spaces S1;0 3 (CT ) and S1;1 3 (CT ) with homogeneous boundary conditions over CT by using interpolating technique, where CT stands for a CT triangulation. The dimensions are related with the numbers of the inter vertices and the singular boundary vertices. The results of this paper can be applied in many elds such as the nite element method for partial di erential equation, computer aided design, numerical approximation, and so on.

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Ahmadzadeh, Asadallah, and Ahmad Teimouri. "Comparison of stress distribution around implants with three different attachments in overdenture supported by four maxillary implants using fi nite element analysis method." Bioscience Biotechnology Research Communications 10, no. 3 (September 25, 2017): 455–62. http://dx.doi.org/10.21786/bbrc/10.3/19.

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12

Phuangmalai, Winna, Mongkol Konghirun, and Nattapon Chayopitak. "A Design Study of 4/2 Switched Reluctance Motor Using Particle Swarm Optimization." ECTI Transactions on Electrical Engineering, Electronics, and Communications 11, no. 1 (April 10, 2013): 56–62. http://dx.doi.org/10.37936/ecti-eec.2013111.170597.

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This paper presents the use of particle swarm optimization (PSO) algorithm applied to the optimal design of the 4/2 switched reluctance motor (SRM). The main advantage of designing 4/2 SRM is the robust rotor structure for high speed unidirectional rotating applications such as the air conditioner's blower. In the designing process, the nite element method magnetics (FEMM) is employed to analyze the designing SRM with its optimized parameters given by PSO. This PSO algorithm is ecient and exible. The objective function is based on the ripple torque minimization with respect to rotor node position. The PSO algorithm is described and the FEMM simulation results with detailed analysis will be given for verifying optimal rotor design by PSO algorithm.

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Lytvynenko, L., S. Pogarsky, and D. Mayboroda. "Analysis and Optimization of the Operating Range of a Monopole Antenna Involving ‘Meander’ Type Slot In- homogeneities." RADIO PHYSICS AND RADIO ASTRONOMY 27, no. 2 (2022): 083–92. http://dx.doi.org/10.15407/rpra27.02.083.

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Subject and Purpose. The paper presents results of numerical modeling and experimental studies of a disk-shaped microstrip antenna involving ‘meander’ type slotted inhomogeneities. The work has been aimed at optimizing the operating range of the antenna and matching it to external circuits through the use of additional structural elements and appropriate feeding techniques. Methods and Methodology. The design features a circular disk-shaped microstrip resonator containing within its plane groups of slotted inhomogeneities which form a segmented meander line, with the segments oriented relative one another at an angle of 120°. The antenna could be fed through a segment of a screened coplanar line. The location of the screening plane of the coplanar line, as well as its dimensions, were variable. Numerical simulation was carried out within the ‘semi-open resonator’ technique using the finite element method. The degree of optimization of the operating range was estimated, based on analyzing spectral characteristics of the antenna, for a variety of its geometric parameters, and the magnitude of the return loss over a given frequency range. Measurements of the VSWR were carried out with reflectometers. Results. Frequency and power characteristics of a monopole, disk-shaped microstrip antenna have been analyzed and optimized over a wide frequency range. Mechanical dimensions of the additional shielding plane and location thereof have been identified as factors having significant influence upon the frequency-dependent, polarizational and power characteristics of the antenna. Conclusions. The operating frequency range, spectral and power characteristics of a monopole, disk-shaped microstrip antenna have been studied both theoretically and experimentally. Numerical simulations were carried out with the use of the fi nite element method. Experimental studies of the frequency characteristics were performed using reflectometry techniques. The antenna considered can find practical application over a wide frequency range, either as a single radiating element in a device or system, or a constituent part of an antenna array.

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Kiselev, I. G., D. N. Kurilkin, and M. A. Shreiber. "Thermal model of an asynchronous traction motor of a diesel locomotive." Proceedings of Petersburg Transport University 2021, no. 4 (December 2021): 460–68. http://dx.doi.org/10.20295/1815-588x-2021-4-460-468.

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Objective: Evaluation of the temperature regime of the windings of an asynchronous traction electric motor with a squirrel-cage rotor (ATED) of the DAT-350 type of a 2TE25A diesel locomotive using the de- Современные технологии – транспорту 467 ISSN 1815-588Х. Известия ПГУПС 2021/4 veloped thermal model. Methods: The research was carried out by the fi nite element method in the application for calculating steady-state temperature fi elds SolidWorks. Resuls: To ensure the specifi ed service life of the ATED, the temperature rise of the windings must be limited to safe values, based on the insulation class. Therefore, it is crucial that designers and operators have access to accurate and computati onally effi cient, physics-based ATED thermal behavior modeling tools. Practical results: Using the proposed methods, it is possible to accurately and effectively evaluate the thermal characteristics of ATED of promising diesel locomotives. In addition, designers can easily and quickly adjust the parameters and performance characteristics of the ATED in such a way that they are conducive to improving the overall performance of the locomotive.

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MOZGOLOV, Mikhail V., and Arina V. TURANOVA. "ON THE EFFECTIVENESS OF OBLIQUE CAISSON REINFORCED CONCRETE FLOORS." Urban construction and architecture 11, no. 3 (December 15, 2021): 20–25. http://dx.doi.org/10.17673/vestnik.2021.03.03.

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The distribution of forces in the beams of a straight and oblique monolithic reinforced concrete caisson fl oor of a square plan is compared. The forces in the beams are determined by well-known analytical methods and using fi nite element models of the SCAD PC. The calculations showed that the forces in the beams of the oblique caisson fl oor, determined analytically and using computer models, diff er signifi cantly, which indicates the complex operation of the spatial system, which is not taken into account by the analytical calculation method based on the theory of calculating plates supported by the contour. The obtained data indicate that a square caisson fl oor with beams installed at an angle of 450 to the reference contour has greater rigidity and lower values of bending moments compared to straight caissons. When the ratio of the sides of the overlap L2 1,5 . L1 to ensure the eff ect of supporting the contour, the location of the beams in relation to the outer contour should be at an angle of 45.

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PANFILOV, Denis A., Vladimir Yu CHEGLINTSEV, Vyacheslav V. ROMANCHIKOV, and Yury V. ZHILTSOV. "STUDIES OF DEFLECTIONS OF STATICALLY DETERMINED REINFORCED CONCRETE BEAMS BASED ON A NONLINEAR DEFORMATION MODEL." Urban construction and architecture 7, no. 4 (December 15, 2017): 9–13. http://dx.doi.org/10.17673/vestnik.2017.04.2.

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In this paper theoretical studies of statically determinated bending reinforced concrete beams of rectangular cross-section on deformation indexes under the eff ect of a short-time uniformly distributed load are viewed. These theoretical studies are based on the main points of the nonlinear deformation model that takes into account the nonlinear work of concrete and fi tments taking into account discrete cracking. The results of calculating the deformation of beams by the method of SP 63.13330.2012 and by authors’ method are proposed as well as the results of a numerical experiment with the identifi cation of the stress-strain state of statically determinated beams in the form of a fi nite element model in the program complex «Lira CAD-2017R3» using a linear and non-linear sett ing of characteristics of concrete and reinforcement. Based on the results of theoretical studies, the calculation results by the methodology of the current standard with a numerical experiment, as well as with the authors’ calculation methodology are compared. All calculations and loading schemes in this technique are given taking into account the possibility of further experimental studies.

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Denkena, B., B. Bergmann, K. Kono, R. Ishiguro, and H. Klemme. "CHARACTERIZATION OF HEAT CONDUCTIVITY OF ECCENTRICALLY ROTATING HEAT PIPES USED FOR COOLING OF MOTOR SPINDLES." MM Science Journal 2021, no. 3 (June 30, 2021): 4698–705. http://dx.doi.org/10.17973/mmsj.2021_7_2021078.

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Heat losses within motor spindles lead to undesired effects such as machining inaccuracies and de-creasing lifetime of the motor and bearings. To reduce thermal loads, complex shaft cooling concepts with costly sealing techniques exist. For this reason, a novel, less costly cooling concept has been de-veloped based on heat pipes with high thermal conductivity and fin-shaped heat exchangers. The de-sign and integration of these heat exchanger elements into a motor spindle is carried out using the fi-nite element method. The aim is to optimize the efficiency of the heat pipes and heat exchangers for optimal shaft cooling performance. For a simulation-based development of a prototype spindle, un-known thermal characteristics of the heat transfer elements must be determined. In this paper, the de-termination of the thermal conductivity of the heat pipes is described. The determination of conductivi-ty is done experimentally. First, the developed test rig and the applied procedure for the determination of the conductivity are shown. Subsequently, the experimental results are presented and discussed. Two types of heat pipes were analyzed: Copper heat pipes with sintered wick structure and nickel-plated copper heat pipes with axial grooves. The influences of rotational speed, heat flow rates and the angle between the heat pipe and main axis of rotation were investigated. The results indicate a distinct dependency of the conductivity on the varied parameters. However, changes of parameter values have very different quantitative and qualitative effects on the determined conductivities de-pending on the type of heat pipe.

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Malecot, Pierrick Malecot, Gemala Hapsari, Sebastien Thibaud, and Fabrice Richard. "A new way to identify thin sheet behaviour: Micro-InDef." International Journal of Quantitative Research and Modeling 1, no. 2 (June 7, 2020): 59–66. http://dx.doi.org/10.46336/ijqrm.v1i2.33.

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Incremental forming is a rapid prototyping process which uses a forming tool toform a sheet metal according to a predetermined trajectory. In this work, a micro incremental deformation test (Micro InDef test) derived from the principle of single point incremental sheet forming is developed and proposed. A complex mechanical loading is applied and has a strong potential for the identication of inelastic behavior using inverse method. In the rst part, this work addresses the parameters identication and validation procedures of ductile damage behavior of ultra-thin sheet metal under very large strain during this instrumented Micro InDef test. An inverse nite element method based on the comparison between numerical and experimental axial forming forces of the micro incremental deformation test is employed to extract a coupled ductile damaged plastic model. In the second part, the objective is to prove the reliability of ductile damage parameters identication using forming force. The richness of data contained in forming force is quantied and compared to the one from tensile test. Firstly, the verication of the estimated parameter's reliability is done via a simple analysis based on the forming force sensitivity to material parameters and secondly by calculating elastoplastic and elastoplastic with ductile damage.

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Tayyebi, K., A. M. Haghighi, and R. Attarnejad. "A new nine-node element for analysing plates with varying thickness using basic displacement functions." Journal of Mechanical Engineering and Sciences 12, no. 4 (December 27, 2018): 4056–71. http://dx.doi.org/10.15282/jmes.12.4.2018.06.0352.

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The capability of the Finite Element Method in producing accurate and efficient results largely depends on the shape functions adopted to frame the displacement field inside the element. In this paper, a new nine-node Lagrangian element was developed to analyse thin plates with varying cross-sections using the shape functions obtained for non-prismatic straight beams with minimum number of elements. The formulated shape functions, which represent vertical displacements and rotations throughout elements, are rooted from a purely mechanical functions called Basic Displacement Functions (BDFs). These functions are obtained by implementing the force method in Euler–Bernoulli beam theory, which ensures that equilibrium equation is satisfied in all interior points of elements. To verify the competency of the proposed element, solutions for the static analysis of isotropic rectangular plates under various loading conditions, together with free vibration analysis of plates with linear thickness variation were obtained and compared with the previous literature. Results showed that the proposed nine-node Lagrangian element was computationally more cost-effective compared to other competing methods when small number of elements is employed.

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BEZIK, DMITRY A. "TESTING THE HYPOTHESIS OF THE COSINE DISTRIBUTION OF STRESSES IN THE SHAFT-HOLE CONTACT." Agricultural engineering, no. 5 (2021): 42–47. http://dx.doi.org/10.26897/2687-1149-2021-5-42-47.

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One of the most common connection types in mechanical engineering and construction is the shaft-hole connection. The mechanical stresses caused by its loading are distributed in the contact zone of the loaded parts of the joint. In some cases, they can lead to destruction. Therefore, while designing, it is important to analyze the mechanical stresses in the contact zone. Traditionally, calculations assume that the contact stresses are distributed according to the cosine law. However, this is not entirely true, especially with diff erent shaft and hole diameters. The authors examined theoretical studies of the contact zone of the shaft and the hole (including the cases of diff erent diameters) and the stress distribution in the contact zone. Based on the studies, they performed numerical calculations in the APMWinMachine environment to determine the stresses in the volume of the shaft and the plate with a hole when loading the shaft-hole connection. The analyses were performed for the two-dimensional case by the fi nite element method in the APMStructure program. The results show that when the diameters in the connection are equal, the stress distribution is close to the cosine law. In this case, only one stress raiser occurs in the contact zone, which is located on the line of action of the loading force. However, if there is a slight discrepancy in the shaft and hole diameters, there are three stress raisers in which the connection may break – the central zone and two side zones. The angular distance between them can be determined based on the known theoretical formulas. The authors made an experiment with a plexiglass model, which qualitatively confi rmed the correctness of the analysis performed.

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Tan, Shujun, Qingwei Wang, Zhigang Wu, Yunfei Yang, and Ziwen Yu. "A method for deriving a non-singular state-space formulation based on Rubin's model for Pogo analysis." Proceedings of the Institution of Mechanical Engineers, Part G: Journal of Aerospace Engineering 233, no. 8 (May 21, 2018): 2717–30. http://dx.doi.org/10.1177/0954410018776811.

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A method for deriving a non-singular state-space formulation based on Rubin's model for Pogo analysis is presented in this study. Because of the non-singularity, the state-space model can be directly used in frequency-domain analyses and time-domain simulations. To describe the assembly method concisely, the dynamic equations of the nine types of independent elements are described in a standard manner. The nine types of elements are divided into two classes according to characteristics of the dynamic equations. The mapping relationship between the local and global numbers of elements and nodes is obtained by numbering all of the elements and nodes. By integrating the element stiffness matrixes to obtain the total stiffness matrix used in the finite element method, the coefficient matrixes of the improved Rubin's model are assembled from the coefficient matrixes of all of the elements according to the mapping relationship. Based on the non-singular model, the time-varying simulation with the nonlinear property of the accumulator can be done conveniently by revising the state-space model. The successful application of this method to a Pogo analysis of a certain type of CZ rocket used in China verifies the correctness and efficiency of the method of this study.

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Noon, Najat Jalil. "Numerical Analysis of Least-Squares Group Finite Element Method for Coupled Burgers' Problem." Baghdad Science Journal 18, no. 4(Suppl.) (December 20, 2021): 1521. http://dx.doi.org/10.21123/bsj.2021.18.4(suppl.).1521.

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In this paper, a least squares group finite element method for solving coupled Burgers' problem in 2-D is presented. A fully discrete formulation of least squares finite element method is analyzed, the backward-Euler scheme for the time variable is considered, the discretization with respect to space variable is applied as biquadratic quadrangular elements with nine nodes for each element. The continuity, ellipticity, stability condition and error estimate of least squares group finite element method are proved. The theoretical results show that the error estimate of this method is . The numerical results are compared with the exact solution and other available literature when the convection-dominated case to illustrate the efficiency of the proposed method that are solved through implementation in MATLAB R2018a.

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WU, HaiJun. "Continuous interior penalty nite element methods for Helmholtz equation with high wave number." SCIENTIA SINICA Mathematica 42, no. 5 (May 1, 2012): 429–44. http://dx.doi.org/10.1360/012012-15.

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Silva, J. B. C., S. S. Mansur, and R. C. Lima. "LARGE EDDY SIMULATION OF TURBULENT INCOMPRESSIBLE FLUID FLOWS BY A NINE-NODES CONTROL VOLUME-FINITE ELEMENT METHOD." Revista de Engenharia Térmica 4, no. 2 (December 31, 2005): 173. http://dx.doi.org/10.5380/reterm.v4i2.5412.

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The main purpose of this work is the numerical computation of turbulent incompressible fluid flows by a nine-node control volume finite element method (CVFEM) using the methodology of large-eddy simulation.. The domain is discretized using nine nodes finite elements and the equations are integrated into control volumes around the nodes of the finite elements. The Navier?Stokes equations are filtered for simulation of the large scales variables and the sub-grid scales stress appearing due to the filtering process are modeled through the eddy viscosity model of Smagorinsky. The two-dimensional benchmark problem of the lid-driven cavity flow is solved to validate the numerical code and preliminary results for the horizontal and vertical velocity profiles at the centerlines of the cavity and the stream functions are presented and compared with available results from the literature.

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Maudy Rizkiana and Kiki Zakiah. "Imparsialitas pada Reportase Investigasi." Bandung Conference Series: Journalism 1, no. 1 (December 7, 2021): 5–9. http://dx.doi.org/10.29313/bcsj.v1i1.22.

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Abstract. This study is conducted through the quantitative content analysis by understanding the application of nine journalistic elements in the elements proportional, and comprehensive, based on objectivity model of McQuail and Westershahl. This research is performed in Tempo Media for a specific case of “Ada Apa dengan Pizza?” and “Siasat di Balik Suap Reklamasi”. Based on this method, the problem in this research is formulated as follow, (1) how application of the nine of element of journalist in impartialityaspect.. This study used a coding sheet with three coder, use IRC and interview to developed the result. The result shows that Tempo Media has implement elemen proportional, and comprehensive on category (1) even handed evalution proven that journalist in writing result of investigate should examined by another three editor (Tempo.co, Tempo Newspaper, and Tempo magazine), (2) equal access proven that they insert two witness to comply proporsional element, (3) Non sensational proven by Tempo media put forward magnitude value, not sensational and novelty, (4) and non evalution proven that Tempo probihited any journalist to write investigate reporting by their opinion. Abstrak. Penelitian ini menggunakan metode analisis isi kuantitatif dengan menggunakan teori Sembilan elemen jurnalistik, focus pada elemen proporsional dan komprehensif, berdasarkan model McQuail dan Westerstahl. Penelitian ini meneliti media Tempo dengan kasus yang yang spesifik yaitu “Ada Apa dengan Pizza?” dan “Siasat di Balik Suap Reklamasi”, berdasarkan metode, pertanyaan penelitian ini dibuat sebagai berikut: (1) Bagaimana penerapan Sembilan elemen jurnalistik dari aspek impartialitas. penerapan dengan menggunakan lembar koding, menggunakan IRC dan wawancara . Hasil penelitian ini menunjukan bahwa media Tempo telah mengimplementasi elemen proporsional dan komprehensif dalam kategori (1) even handed evalution dibuktikan dengan wartawan dalam menuliskan laporan investigasi harus diuji kembali oleh tiga redaksi (Tempo.co, majalah Tempo, dan majalah Tempo ), (2) equal access dibuktikan wartawan selalu menuliskan dua saksi untuk memenuhi nilai proporsional, (3) non sensational dibuktikan dengan media Tempo dalam melakukan investigasu mengedepankan nilai magnitude bukan sensational atau pun kebaharuan, dan (4) non evaluative dibuktikan Tempo melarang semua jurnalis yang menuliskan investigasi untuk memasukan opini mereka.

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Liu, Wang Sheng, Ya An Li, Lin Cui, and Ming Huan Wang. "The Mutual Impedance Analysis of a Broadband Dense Plane Array." Advanced Materials Research 443-444 (January 2012): 1019–25. http://dx.doi.org/10.4028/www.scientific.net/amr.443-444.1019.

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Due to the mutual radiation impedance may influence acoustics performance of a broadband dense plane array seriously, the expression of mutual radiation impedance among the transducers is developed according to the definition of mutual radiation impedance based on BEM（Boundary Element Method）. BEM model is established for acoustic radiation of a broadband dense plane array with nine elements. Sound pressure distribution of the nine-element array is solved using SYSNOISE software. And mutual radiation impedances are calculated on the condition of knowing surface normal velocity. Acoustic performance of the nine-element array is analysed through mutual radiation impedance. The influence of mutual impedance on acoustics performance for nine-element array is verified by comparing with measured curve of transducer conductance. The results show that it is successful to calculate mutual impedance of the array and predict acoustics performance using BEM.

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Kosior, Grzegorz, Marina Frontasyeva, Zbigniew Ziembik, Inga Zincovscaia, Agnieszka Dołhańczuk-Śródka, and Barbara Godzik. "The Moss Biomonitoring Method and Neutron Activation Analysis in Assessing Pollution by Trace Elements in Selected Polish National Parks." Archives of Environmental Contamination and Toxicology 79, no. 3 (September 8, 2020): 310–20. http://dx.doi.org/10.1007/s00244-020-00755-6.

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Abstract The concentrations of trace elements in feather moss Pleurozium schreberi (Brid.) Mitt. were used to indicate the relative levels of air pollution by trace elements in Polish national parks. Pleurozium schreberi was collected from nine national parks. The highest concentrations were recorded in the moss samples from the southern and most industrialised part of the country; the lowest from northern and north-eastern Poland. A comparison of data obtained from Polish national parks in the 1970s and 1990s showed a significant decrease in the concentrations of heavy metals. In the linear covariability estimation, the t quantile approach was used for multi-element comparison. A number of positive covariabilities were observed. This is a result of anthropogenic activity and the geochemical characteristics of the local environment, including crust composition to which soil composition is related. The statistical approach of t quantile to study common relationships between element concentrations can be used in the interpretation of biomonitoring research results in similar studies.

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Akpobi, John A., and E. D. Akpobi. "Development of a Model for Analysing Radial Flow of Slightly Compressible Fluids." Advanced Materials Research 62-64 (February 2009): 629–36. http://dx.doi.org/10.4028/www.scientific.net/amr.62-64.629.

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In this work, we develop a finite element-finite difference method to solve the differential equation governing the radial flow of slightly compressible fluids. The finite element method is used to carry out spatial approximations so as to study the variation of fluid properties at the various nodes to which effect we divided the entire radial domain of the fluid into a mesh of four radial 1-D quadratic elements which exposes nine nodes to intense study. Time approximation is done with the aid of the Crank-Nicolson finite difference scheme.

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Ramalho, L. D. C., J. Belinha, and R. D. S. G. Campilho. "A New Crack Propagation Algorithm Combined with the Finite Element Method." Journal of Mechanics 36, no. 4 (April 1, 2020): 405–22. http://dx.doi.org/10.1017/jmech.2020.1.

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ABSTRACTThe prediction of crack propagation is an important engineering problem. In this work, combined with triangular plane stress finite elements, a new remeshing algorithm for crack opening problems was developed. The proposed algorithm extends the crack iteratively until a threshold maximum crack length is achieved. The crack propagation direction is calculated using the maximum tangential stress criterion. In this calculation, in order to smoothen the stress field in the vicinity of the crack tip, a weighted average of the stresses of the integration points around the crack tip is considered. The algorithm also ensures that there are always at least eight elements and nine nodes surrounding the crack tip, unless the crack tip is close to a domain boundary, in which case there can be fewer elements and nodes around the crack tip.Four benchmark tests were performed showing that this algorithm leads to accurate crack paths when compared to findings from previous research works, as long as the initial mesh is not too coarse. This algorithm also leads to regular meshes during the propagation process, with very few distorted elements, which is generally one of the main problems when calculating crack propagation with the finite element method.

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Lou, Yun-xiao, Xian-shu Fu, Xiao-ping Yu, Zi-hong Ye, Hai-feng Cui, and Ya-fen Zhang. "Stable Isotope Ratio and Elemental Profile Combined with Support Vector Machine for Provenance Discrimination of Oolong Tea (Wuyi-Rock Tea)." Journal of Analytical Methods in Chemistry 2017 (2017): 1–8. http://dx.doi.org/10.1155/2017/5454231.

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This paper focused on an effective method to discriminate the geographical origin of Wuyi-Rock tea by the stable isotope ratio (SIR) and metallic element profiling (MEP) combined with support vector machine (SVM) analysis. Wuyi-Rock tea (n=99) collected from nine producing areas and non-Wuyi-Rock tea (n=33) from eleven nonproducing areas were analysed for SIR and MEP by established methods. The SVM model based on coupled data produced the best prediction accuracy (0.9773). This prediction shows that instrumental methods combined with a classification model can provide an effective and stable tool for provenance discrimination. Moreover, every feature variable in stable isotope and metallic element data was ranked by its contribution to the model. The results show that δ2H, δ18O, Cs, Cu, Ca, and Rb contents are significant indications for provenance discrimination and not all of the metallic elements improve the prediction accuracy of the SVM model.

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Ölmez, Hasan, and Ertekin Bayraktarkatal. "Maximum Load Carrying Capacity Estimation of The Ship and Offshore Structures by Progressive Collapse Approach." Polish Maritime Research 23, no. 3 (September 1, 2016): 28–38. http://dx.doi.org/10.1515/pomr-2016-0029.

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Abstract The aim of the paper is to represent step by step progressive collapse analysis for maximum load carrying capacity estimation of a hull girder by using variant of Smith Method, named HULT by authors, with different element separation including single plates, stiffeners, hard corners and stiffened panels. The structural elements that form the ships and offshore structures are exposed to large vertical bending moments and especially compression or tension forces in the longitudinal axis in case of hogging and sagging under bad sea conditions. In recent years, it becomes very important and valuable to practically, fast and nearly correct estimation of the maximum vertical bending moment just before breaks in two (collapse) under the worst conditions. The optimum (accuracy, time, practicality) estimation of these values depend on how accurate the stress-strain relation of the structural elements are established. In this first part of study, the ultimate strength behaviour of the stiffened panels in decks, bottoms and sides is estimated by developed semi-analytical method with updated orthotropic panel calculation approach under uniaxial (only longitudinal axis) compression loads. The second part of calculation is focused on the progressive collapse analysis of hull girders under longitudinal uniaxial compression with Smith Method but with different element discretization in contrast to the conventional beam-column elements. Also some benchmark studies of such methods on ultimate limit state assessment of stiffened panels and nine benchmark hull girders of ships are conducted, using some candidate methods such as IACS Common Structural Rules (CSR), FEA with Ansys v13 and HULT prepared by authors. The results from the tests, FEM analysis and different computational approaches are compared to determine performance of the method.

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Cho, Maenghyo, and Jun-Sik Kim. "A postprocess method for laminated shells with a doubly curved nine-noded finite element." Composites Part B: Engineering 31, no. 1 (January 2000): 65–74. http://dx.doi.org/10.1016/s1359-8368(99)00059-1.

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Cheung, Y. K., and Chen Wanji. "Refined nine-parameter triangular thin plate bending element by using refined direct stiffness method." International Journal for Numerical Methods in Engineering 38, no. 2 (January 30, 1995): 283–98. http://dx.doi.org/10.1002/nme.1620380208.

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Pan, Hui, Wei Zhou, Dezhong Chen, Hongling Zhang, and Yunchun Han. "Gas coal delamination recognition method based on the Fisher discriminant function of trace element characteristics." Journal of Geophysics and Engineering 19, no. 6 (November 8, 2022): 1235–45. http://dx.doi.org/10.1093/jge/gxac081.

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Abstract Numerous geological factors will affect determining the well bottom position by well depth during the construction of coalbed methane wells, resulting in inaccurate results. By using the trace element characteristics of coal samples to determine the source layer of coal samples, it is possible to avoid making incorrect assumptions. The groove method was used in this study to collect 40 gas coal samples from seven gas coal seams in Dingji Mine, which were then sealed and stored. The contents of 40 different trace elements were analyzed in the samples, and the types and content characteristics of trace elements in each coal seam were determined preliminarily through content distribution map analysis. Simultaneously, the SPSS analysis software was used to analyze the 1600 trace element test data from various coal seams, and cluster analysis was performed using the average link method between classes. The clustering tree diagram was created, and the discrimination was calculated using the distance between classes and samples. This study analyzed the typical explanatory variables and established the Fisher discriminant function for coal seam identification. Accordingly, identifying gas coal stratification requires only measuring the concentrations of nine trace elements (typical explanatory variables) in the coal seam being discriminated against. This method can be used in Dingji mine to determine the final hole horizon of surface coalbed methane wells and eliminates the risk of accidentally exposing coal seams during the excavation of an underground roadway.

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Bermudez, J., A. Illarramendi, and I. Berges. "Binding SNOMED CT Terms to Archetype Elements." Methods of Information in Medicine 54, no. 01 (2015): 45–49. http://dx.doi.org/10.3414/me13-02-0022.

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SummaryIntroduction: This article is part of the Focus Theme of Methods of Information in Medicine on “Managing Interoperability and Complexity in Health Systems”.Background: The proliferation of archetypes as a means to represent information of Electronic Health Records has raised the need of binding terminological codes – such as SNOMED CT codes – to their elements, in order to identify them univocally. However, the large size of the terminologies makes it difficult to perform this task manually.Objectives: To establish a baseline of results for the aforementioned problem by using off-the-shelf string comparison-based techniques against which results from more complex techniques could be evaluated.Methods: Nine Typed Comparison Methods were evaluated for binding using a set of 487 archetype elements. Their recall was calculated and Friedman and Nemenyi tests were applied in order to assess whether any of the methods outperformed the others.Results: Using the qGrams method along with the ‘Text’ information piece of archetype elements outperforms the other methods if a level of confidence of 90% is considered. A recall of 25.26% is obtained if just one SNOMED CT term is retrieved for each archetype element. This recall rises to 50.51% and 75.56% if 10 and 100 elements are retrieved respectively, that being a reduction of more than 99.99% on the SNOMED CT code set.Conclusions: The baseline has been established following the above-mentioned results. Moreover, it has been observed that although string comparison-based methods do not outperform more sophisticated techniques, they still can be an alternative for providing a reduced set of candidate terms for each archetype element from which the ultimate term can be chosen later in the more-than-likely manual supervision task.

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Li, Yu, and Jin Shun Feng. "The Nice Characters of Biorthogonal Four-Element Wavelet Packets with Two-Scale." Key Engineering Materials 460-461 (January 2011): 351–56. http://dx.doi.org/10.4028/www.scientific.net/kem.460-461.351.

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In this article, the notion of orthogonal nonseparable four-dimensional wavelet packets, which is the generalization of orthogonal univariate wavelet packets, is introduced. A new approach for constructing them is presented by iteration method. A novel approach for constructing two-directional biorthogonal wavelet packets is developed. The biorthogonality property of four-dimensional wavelet packets is discussed. Three biorthogonality formulas concerning these wavelet packets are estabished. A constructive method for affine frames of is proposed.

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Choi, Yoojin, Tae Jung Park, Doh C. Lee, and Sang Yup Lee. "Recombinant Escherichia coli as a biofactory for various single- and multi-element nanomaterials." Proceedings of the National Academy of Sciences 115, no. 23 (May 21, 2018): 5944–49. http://dx.doi.org/10.1073/pnas.1804543115.

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Nanomaterials (NMs) are mostly synthesized by chemical and physical methods, but biological synthesis is also receiving great attention. However, the mechanisms for biological producibility of NMs, crystalline versus amorphous, are not yet understood. Here we report biosynthesis of 60 different NMs by employing a recombinant Escherichia coli strain coexpressing metallothionein, a metal-binding protein, and phytochelatin synthase that synthesizes a metal-binding peptide phytochelatin. Both an in vivo method employing live cells and an in vitro method employing the cell extract are used to synthesize NMs. The periodic table is scanned to select 35 suitable elements, followed by biosynthesis of their NMs. Nine crystalline single-elements of Mn3O4, Fe3O4, Cu2O, Mo, Ag, In(OH)3, SnO2, Te, and Au are synthesized, while the other 16 elements result in biosynthesis of amorphous NMs or no NM synthesis. Producibility and crystallinity of the NMs are analyzed using a Pourbaix diagram that predicts the stable chemical species of each element for NM biosynthesis by varying reduction potential and pH. Based on the analyses, the initial pH of reactions is changed from 6.5 to 7.5, resulting in biosynthesis of various crystalline NMs of those previously amorphous or not-synthesized ones. This strategy is extended to biosynthesize multi-element NMs including CoFe2O4, NiFe2O4, ZnMn2O4, ZnFe2O4, Ag2S, Ag2TeO3, Ag2WO4, Hg3TeO6, PbMoO4, PbWO4, and Pb5(VO4)3OH NMs. The strategy described here allows biosynthesis of NMs with various properties, providing a platform for manufacturing various NMs in an environmentally friendly manner.

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Mai, Khoi D., William F. Cofer, and Donald A. Bender. "Quasi-Dynamic Implicit Finite Element Analysis of Steel-Clad, Wood-Framed Shear Walls." Transactions of the ASABE 63, no. 6 (2020): 1619–28. http://dx.doi.org/10.13031/trans.13846.

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HighlightsA new finite element modeling method was developed to predict performance of steel-clad, wood-framed diaphragms.The new method overcomes limitations of previous models and accurately predicts yielding and buckling behaviors.The new method will save time and money in developing design values for steel-clad, wood-frame diaphragms.Abstract. Various finite element codes and solution techniques have been developed for steel-clad, wood-framed (SCWF) shear walls over the past few decades. Most previous finite element models for SCWF shear walls under monotonic loading were based on a static implicit solution technique. Previous researchers stated that the static implicit technique showed promise for modeling SCWF diaphragms; however, the solution technique failed to converge to equilibrium as local instabilities in the form of snap-through buckling of steel cladding occurred or geometric nonlinearities were included in the model. In this study, a nonlinear quasi-dynamic implicit finite element analysis (FEA) of SCWF shear walls subjected to monotonic loading was developed to overcome the deficiencies of the static implicit approach. Three types of elements were used, including beam elements to model wood framing, shell elements to model steel cladding, and nonlinear spring elements to model connectors. Screw connector tests were conducted to obtain the load-displacement constitutive relationships needed for finite element models. Nine types of SCWF shear walls with and without lap seam stitching were tested to validate the finite element model. The ratios of predicted to test values for ultimate shear strength averaged 0.97 with a coefficient of variation (COV) of 8.1%, and the ratios for effective shear modulus averaged 1.13 with a COV of 30%. The quasi-dynamic implicit FEA is a significant improvement over previous static implicit techniques and should be a useful tool to predict the ultimate shear strength and effective shear modulus of SCWF shear walls under monotonic loading. Keywords: Diaphragm design, Post-frame building, Steel-clad wood-frame diaphragm.

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Zhao, Xiaopeng, Fengnan Liu, and Bo Liu. "FINITE ELEMENT METHOD FOR A NONLINEAR DIFFERENTIAL EQUATION DESCRIBING CRYSTAL SURFACE GROWTH." Mathematical Modelling and Analysis 19, no. 2 (April 15, 2014): 155–68. http://dx.doi.org/10.3846/13926292.2014.909372.

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In this paper, for a nonlinear differential equation describing crystal surface growth, the finite element method is presented. A nice order error estimates is derived by means of a finite element projection approximation.

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Welna, Maja, Anna Szymczycha-Madeja, and Pawel Pohl. "Simplified ICP OES-Based Method for Determination of 12 Elements in Commercial Bottled Birch Saps: Validation and Bioaccessibility Study." Molecules 25, no. 5 (March 10, 2020): 1256. http://dx.doi.org/10.3390/molecules25051256.

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Commercially bottled birch saps (BSs) were analyzed for several nutrient (Ca, Cu, Fe, Mg, and Zn) and toxic (As, Cd, Ni, and Pb) elements using inductively coupled plasma optical emission spectrometry (ICP OES). The method was validated under the conditions of several sample preparation procedures, including a traditional digestion as well as alternative non-digestion schemes. It was found that the direct analysis of untreated BSs gives the best results, i.e., limits of detection at 0.02–5.8 ng mL−1, precision better than 5%, accuracy from 98.0% to 104.5% and determination of 12 elements in a short time (~1 min per sample). The multi-element analysis of nine commercially available bottled BSs showed that they contained mainly Mg and Ca, small quantities of Mn, Zn, Cu, and Fe, but are free from toxic elements such as As, Cd, Ni, and Pb. Additionally, the nutritional value of BSs was examined using in vitro gastro-intestinal digestion (GID) to determine the bioaccessible fraction of elements. Accordingly, bioaccessibility of nutritious ones (Ca, Cu, Fe, Mg, Zn) was <40%. Drinking daily 1 L of BSs covered <2.5% of recommended dietary intakes (RDIs) of the aforementioned elements. Only the bioaccessibility of Mn highly contributes to its RDI.

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Liu, Qi, Yan Yu, and Pingjian Ming. "A high-order control volume finite element method for thermoelastic analysis of functionally graded solids with mixed grids." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 233, no. 11 (November 14, 2018): 3994–4013. http://dx.doi.org/10.1177/0954406218811363.

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In this article, a new two-dimensional control volume finite element method has been developed for thermoelastic analysis in functionally graded materials. A nine-node quadrilateral element and a six-node triangular element are employed to deal with the mixed-grid problem. The unknown variables and material properties are defined at the node. The high-order shape functions of six-node triangular and nine-node quadrilateral element are employed to obtain the unknown variables and their derivatives. In addition, the material properties in functionally graded structure are also modeled by applying the high-order shape functions. The capabilities of the presented method to heat conduction problem, elastic problem, and thermoelastic problem have been validated. First, the defined location of material properties is found to be important for the accuracy of the numerical results. Second, the presented method is proven to be efficient and reliable for the elastic analysis in multi-phase materials. Third, the presented method is capable of high-order mixed grids. The memory and computational costs of the presented method are also compared with other numerical methods.

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Sell, Bryan Keith, and Scott Douglas Samson. "A tephrochronologic method based on apatite trace-element chemistry." Quaternary Research 76, no. 1 (July 2011): 157–66. http://dx.doi.org/10.1016/j.yqres.2011.03.007.

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AbstractGeochemical correlation of ash-fall beds with conventional tephrochronologic methods is not feasible when original glass composition is altered. Thus, alternative correlation methods may be required. Initial studies of heavily altered Paleozoic tephra (K-bentonites) have suggested the potential for employing trace-element concentrations in apatite as ash-fall bed discriminators. To further test the utility of apatite trace-element tephrochronology, we analyzed apatite phenocrysts from unaltered volcanic rocks with an electron microprobe: nine samples from rocks erupted during the Quaternary and one sample from a rock erupted during the Paleogene. The resulting apatite trace-element data provide unique bed discriminators despite within-crystal variability. Each of the volcanic rocks studied possesses unique trends in Mg, Cl, Mn, Fe, Ce and Y concentrations in apatite. The results from this study establish an important tephrochronologic method that can be applied to nearly all portions of the Phanerozoic stratigraphic record and greatly assist development of an advanced timescale. In addition to establishing a fingerprint for a particular eruption, apatite chemistry provides useful information about the source magma.

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Lampe, Kristian, Marjukka Mäkelä, Marcial Velasco Garrido, Heidi Anttila, Ilona Autti-Rämö, Nicholas J. Hicks, Björn Hofmann, et al. "The HTA Core Model: A novel method for producing and reporting health technology assessments." International Journal of Technology Assessment in Health Care 25, S2 (December 2009): 9–20. http://dx.doi.org/10.1017/s0266462309990638.

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Objectives: The aim of this study was to develop and test a generic framework to enable international collaboration for producing and sharing results of health technology assessments (HTAs).Methods: Ten international teams constructed the HTA Core Model, dividing information contained in a comprehensive HTA into standardized pieces, the assessment elements. Each element contains a generic issue that is translated into practical research questions while performing an assessment. Elements were described in detail in element cards. Two pilot assessments, designated as Core HTAs were also produced. The Model and Core HTAs were both validated. Guidance on the use of the HTA Core Model was compiled into a Handbook.Results: The HTA Core Model considers health technologies through nine domains. Two applications of the Model were developed, one for medical and surgical interventions and another for diagnostic technologies. Two Core HTAs were produced in parallel with developing the model, providing the first real-life testing of the Model and input for further development. The results of formal validation and public feedback were primarily positive. Development needs were also identified and considered. An online Handbook is available.Conclusions: The HTA Core Model is a novel approach to HTA. It enables effective international production and sharing of HTA results in a structured format. The face validity of the Model was confirmed during the project, but further testing and refining are needed to ensure optimal usefulness and user-friendliness. Core HTAs are intended to serve as a basis for local HTA reports. Core HTAs do not contain recommendations on technology use.

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Ueno, M., and S. Tanoue. "Properties of the Magnetoresistive Elements for NiFe/Cu Multilayers Using the SAL Biasing Method." Journal of the Magnetics Society of Japan 19, no. 2 (1995): 401–4. http://dx.doi.org/10.3379/jmsjmag.19.401.

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Vynnykov, Yu L., I. V. Miroshnychenko, О. М. Landar, V. М. Zotsenko, and P. M. Omelchenko. "LONG-TERM SUBSIDENCE OF A MULTISTORY BUILDING ON THE BASE REINFORCED WITH SOIL CEMENT ELEMENTS." ACADEMIC JOURNAL Series: Industrial Machine Building, Civil Engineering 2, no. 49 (October 17, 2017): 234–42. http://dx.doi.org/10.26906/znp.2017.49.850.

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The methodology and results of long-term geodetic observation at subsidence of nine-ten storey building with a strip cast-in-place foundation on sandy and peaty base reinforced with soil cement elements at the process of its construction and exploitation are presented in the article. The correctness of elastic-plastic model use with Mohr Coulomb strength criterion and planar task finite element method for the evaluation of the deformed state «strip foundation – reinforced soil layer – the natural basis» system are substantiated.

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Sergeev, Yu A., A. A. Dolgalev, D. Z. Choniashvili, and V. M. Avanisyan. "Application of the finite element analysis in the development of new dental implant systems. Literature review." Medical alphabet 1, no. 1 (March 17, 2023): 18–23. http://dx.doi.org/10.33667/2078-5631-2023-1-18-23.

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Introduction. The development of new dental implants in the context of the booming domestic industry makes it possible to find alternative options in the treatment of clinically difficult situations, to select the necessary individual solution during dental implant surgery, and consequently, to perform the surgery in an error-free manner and achieve the desired results. The development of a dental implant is a multistep process, and the characteristics of the implant material and its biophysical characteristics must be studied in detail until the implant is integrated into the bone tissue. The aim of the study: to estimate the opportunities and prospects of applying the finite elements method by developing the new systems of dental implants according to the literature data. Material and methods. A search was carried out in the national digital libraries e-library, CyberLeninka, as well as PubMed, Medline, Web of Science and Google Scholar using the following keywords: dental implant, finite-element analysis, mathematical model. Sixty-nine papers were selected and analysed. Results. The finite element method is an accurate method to analyse the implant being developed, but it has certain limits, because in the finite element mesh, the implant-bone interface is a continuous relationship. The absence of micro-movement at the implant-bone interface during loading is different from the actual clinical situation. The expected 100 % osseointegration based on 3D-modelling can’t be an ideal option and never corresponds to the reality in the clinical situation. However, the use of the finite element method makes it possible to test single loads and inclination angles, which in the clinical situation is very rare.

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Lei, Zhang, Chang Tian Qing, and Su Kui Feng. "A Fault Detection Method Based on Feedforward Compensation in Mechatronic Control System." Applied Mechanics and Materials 664 (October 2014): 360–64. http://dx.doi.org/10.4028/www.scientific.net/amm.664.360.

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For the fault detection of mechatronic control system, based on observer a feedforward compensation approach was presented. The model of a mechatronic control system was investigated and divided into two loops for disturbance compensation and fault detection. The external disturbance of the vehicle was analyzed, and the relationship between the support shaft friction moment as main disturbance element and the attitude effect of the vehicle was built by the way of data curve fitting. The adjustment coefficients were proposed respectively in nine kinds of running section of the vehicle, because disturbance was very complicated and time-variant in different section. Fault detection observer was designed to generate residuals in the inner loop, and the whole residual was calculated. The compensation was deduced in accordance with responses produced by the disturbance, so the disturbance could be compensated. Band filter was proposed for other noises. Finally, an example was presented to illustrate the proposed approach. The simulation results showed that the disturbance elements can be compensated rapidly.

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Jiang, Lv, Lifa Hu, Qili Hu, Xingyu Xu, Jingjing Wu, Lin Yu, and Yang Huang. "Sixty-Nine-Element Voice Coil Deformable Mirror for Visible Light Communication." Photonics 10, no. 3 (March 17, 2023): 322. http://dx.doi.org/10.3390/photonics10030322.

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To overcome the atmospheric turbulence aberration, and improve the quality of light beam in visible light communication (VLC), a compact 69-element deformable mirror (DM) using micro voice coil actuators was designed based on systematic theoretical analysis. The structural parameters of the micro voice coil actuator were optimized by electromagnetic theory and the finite element method. The DM was optimized from the aspects of thermal deformation, response time, coupling coefficient, and other parameters. Finally, wavefront fitting and residual calculation were completed according to the influence function. The optimized voice coil deformable mirror (VCDM) has a large phase stroke, good thermal stability, a short response time of less than 0.7 ms, and a large first resonance of 2045 Hz. The fitting residuals of the VCDM for the first 10 Zernike modes with a PV value of 8 μm are all below 10 nm (RMS). Compared with a similar DM, the obtained results from our compact VCDM indicate that it has a higher wavefront fitting precision. VCDM corrected complex random aberrations in the VLC scenario and improved the coupling efficiency of the signal beam, proving that the compact VCDM with high performance and low cost has a good application prospect in VLC systems.

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Sergeev, Yu A., A. A. Dolgalev, D. Z. Choniashvili, and V. M. Avanisyan. "THE USAGE OF THE FINITE ELEMENT ANALYSIS IN THE DESIGN OF NEW DENTAL IMPLANT SYSTEMS." International journal of Innovative Medicine, no. 1 (August 8, 2023): 19–23. http://dx.doi.org/10.33667/2782-4101-2023-1-19-23.

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Introduction. The development of new dental implants in the context of the booming domestic industry makes it possible to find alternative options in the treatment of clinically difficult situations, to select the necessary individual solution during dental implant surgery and consequently to perform the surgery in an error-free manner and achieve the desired results. The development of a dental implant is a multistep process, and the characteristics of the implant material and its biophysical characteristics must be studied in detail until the implant is integrated into the bone tissue.The aim of the study: to estimate the opportunities and prospects of applying the finite elements method by developing the new systems of dental implants according to the literature data.Materials and methods. A search was carried out in the national digital libraries e-library, CyberLeninka, as well as PubMed, Medline, Web of Science and Google Scholar using the following keywords: dental implant, finiteelement analysis, mathematical model. Sixty-nine papers were selected and analysed.Results. The finite element method is an accurate method to analyse the implant being developed, but it has certain limitations, because in the finite element mesh, the implant-bone interface is a continuous relationship. The absence of micro-movement at the implant-bone interface during loading is different from the actual clinical situation. The expected 100 % osseointegration based on 3D-modelling can’t be an ideal option and never corresponds to the reality in the clinical situation. However, the use of the finite element method makes it possible to test single loads and inclination angles, which in the clinical situation is very rare

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SERA, K., S. GOTO, C. TAKAHASHI, and Y. SAITOH. "QUANTITATIVE ANALYSIS OF UNTREATED OIL SAMPLES IN IN-AIR PIXE." International Journal of PIXE 20, no. 03n04 (January 2010): 77–84. http://dx.doi.org/10.1142/s0129083510001999.

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The method of quantitative analysis of oil samples in in-air PIXE has been developed on the basis of a standard-free method. The components of the continuous X-rays originated from air and backing film can be exactly subtracted using a blank spectrum after normalization by the yields of Ar K -α X-rays. The method was developed using nine oil samples including standard oils and its accuracy was confirmed by comparing the results with those obtained by the internal-standard method. Validity of the method for practical oil samples was confirmed for various kinds of oils such as engine, machine and cooking oils. It was found that the method is effective for various kinds of oils whatever elements we designate as an index element.

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Journal articles on the topic 'Nite element method'

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