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This study reports the oldest fossil record of the genus Adina, A. vastanenesis n. sp., from the early Eocene of Vastan lignite mine (Cambay Shale Formation), Surat district, Gujarat. This fossil wood is characterized by diffuse porous wood, predominantly solitary tylosed vessels, simple perforations, scanty paratracheal to diffuse to sometimes diffuse in aggregate axial parenchyma, predominantly uniseriate to occasionally biseriate rays, and non septate fibres with bordered pits and shows its best resemblance with the modern species, Adina multifolia Haviland, belonging to the tribe Naucleeae (subfamily Cinchonoideae) of the family Rubiaceae. The present discovery becomes the first fossil record of the wood of Adina, which provides an insight about the Gondwanan origin either for the genus Adina or the tribe Naucleeae and its further dispersal to Southeast Asia.

Even though two-phase heat transfer of refrigerants in minichannel heat sinks has been studied extensively, there is still a demand for improvements in overall thermal performance of miniature heat transfer exchangers. Experimental investigation and sophisticated heat transfer calculations with respect to heat transfer devices are still needed. In this work, a time-dependent experimental study of subcooled boiling was carried out for FC-72 flow in a heat sink, comprising of five asymmetrically heated minichannels. The heater surface temperature was continuously monitored by an infrared camera. The boiling heat transfer characteristics were investigated and the effect of the mass flow rate on the heat transfer coefficient was studied. In order to solve the heat transfer problem related to time-dependent flow boiling, two numerical methods, based on the FEM were applied, and based on the Trefftz functions (FEMT) and using the ADINA program. The results achieved with these two calculation methods were explored with an emphasis on the impact of the mass flow rate (range from 5 to 55 kg/h) on the resulting heat transfer coefficient. It was found that, with increasing mass flow, the heat transfer coefficient increased. Good agreement was found between the heat transfer coefficients, determined according to two numerical methods and the simple 1D calculation method.

PurposeThe purpose of the paper is researching on the motion law of fiber in the vortex field inside the nozzle.Design/methodology/approachA three-dimensional calculation model was established using the MVS861 (Muratec Vortex Spinning) air-jet vortex-spinning nozzle as the prototype, and the fluid–solid coupling calculation module in the finite element calculation software ADINA (Adina System) was used to numerically analyze the fiber-air flow two-phase coupling. At the same time, the effect of the air pressure at the nozzle on the two-phase flow is studied.FindingsThe results show that after the air flow ejected through the nozzle, a vortex field will be generated in the flow field to push the internal fiber to move toward the nozzle outlet in a wave motion; as the air pressure at the nozzle increases, the fiber movement period becomes shorter and the oscillation frequency becomes higher; increasing the air pressure at the spray hole can improve the working efficiency of fiber twisting and wrapping.Originality/valueThe research present an effective and feasible theoretical model and method for the motion law of fiber in the vortex field inside the nozzle based on ADINA fluid–structure coupling model.

Development of the designing process in civil engineering brings the possibility for more complex analysis of the structures. Computational software can be helpful for regular design but also for identification and solving of more specified problems. Finite Element Method (FEM) became one of the most used numerical methods. Numerous commercial programs are based on this method. However, these programs are more complex and require skilled designer to fully utilize their potential. This article brings the lead to apply the FEM method implemented in commercial software ADINA to solve the problem of structural mechanics. It is necessary to connect the theoretical approach of FEM modeling and experience from real case problems. Skilled designer can calibrate the numerical model to obtain relevant outputs. However, certain cases still require a detailed and individual approach during designing that is verified by the in-situ monitoring and observation. Lead of the student to the flexible treatment of the design is one of the important tasks of the educational process. This involves the basic knowledge about appropriate analysis of the problem for effective utilization of the computational software for particular applications even for more complex solutions.

Static and dynamic behavior of above-ground steel storage oil tanks resting on end bearing piles or stone columns are studied and analyzed using ADINA (2019) program. The studied soil profile is an upper soft clay soil layer, followed by an extended dense sand layer. The main purpose of this research is to explore to what extent stone columns can be used as an effective alternative to concrete piles under steel storage tanks. Therefore, many three-dimensional numerical models are conducted to analyze and study the performance of such tanks in both static and dynamic cases. Ten of the studied cases are steel tanks resting over stone columns with different numbers and properties. On other hand, one model studied the behavior of steel tank resting on large diameter concrete piles. Results indicate that stone columns can be used instead of end bearing piles as long as the computed settlements are safe. In addition, stone columns are behaving better than concrete piles in decreasing of hoop stress in tank shell. It is also noticed that stone columns with high elastic modulus are effective in reducing the sloshing height of the oil surface during earthquakes.

Cavitation is common in electrohydraulic servo valves and often adversely affects their performance. This study explores the influence of pre-stage cavitation on the performance of double-nozzle flapper pressure servo valves. The mechanism of cavitation is theoretically studied, a dynamic model of cavitation bubble motion is deduced, and the main factors affecting the development and variation of cavitation are determined. The software ADINA is used to establish a servo valve pre-stage fluid–structure interaction (FSI) model using the finite volume method. Cavitation is introduced to the model to conduct an FSI simulation of the influence of pre-stage cavitation on the performance of double-nozzle flapper pressure servo valves with nozzle diameters of 0.5, 0.55, 0.6, and 0.7 mm. An experiment on the servo valve is carried out to verify the simulation results. The simulation and experiment show that a nozzle diameter that is too small or large weakens the performance of a servo valve, and 0.6 mm is an ideal diameter; asymmetric double nozzles may reduce or improve the performance of a servo valve, and a combination of 0.6 and 0.55 mm nozzles is optimal; pre-stage cavitation influences the performance of a servo valve by changing the size and pressure gain of the dead zone; and excessive cavitation strength decreases or increases the dead zone and increases the pressure gain.

The oscillating buoy wave energy converter (OBWEC) captures wave energy through the undulating movement of the buoy in the waves. In the process of capturing wave energy, the hydrodynamic performance of the buoy plays an important role. This paper designed the “Haida No. 1” OBWEC, in which the buoy adopts a form of swinging motion. In order to further improve the hydrodynamic performance of the buoy, a 2D numerical wave tank (NWT) model is established using ADINA software based on the working principle of the device. According to the motion equation of the buoy in the waves, the influence of the buoy shape, arm length, tilt angle, buoy draft, buoy width, wave height and Power Take-off (PTO) damping on the hydrodynamic performance of the buoy is studied. Finally, a series of physical experiments are performed on the device in a laboratory pool. The experimental results verify the consistency of the numerical results. The research results indicate that the energy conversion efficiency of the device can be improved by optimizing the hydrodynamic performance of the buoy. However, the absorption efficiency of a single buoy for wave energy is limited, so it is very difficult to achieve full absorption of wave energy.

Sloshing is associated with the structural safety of liquid storage vessel. Installing the baffles inside the containers would be beneficial for the mitigating the damage due to the severe sloshing. In this study, an innovative type of double-side curved baffle was proposed to evaluate its effect on reducing sloshing in a rectangular tank under surge and pitch excitation. For comparison with conventional baffles, effects of the vertical baffle and the T-type baffle on mitigating sloshing were also studied experimentally and numerically by analyzing the free surface wave elevation as well as the hydrodynamic pressure on the tank wall. The effective stress at the double-side curved baffle along the height direction of the baffle is much smaller than that at the T-type baffle although they have the same mitigation effect on sloshing wave heights. The sloshing-induced effective stress on the double-side curved baffles was analyzed by varying their radian. Findings show that the effective stress on the baffle tends to decrease with the increase in the radian. The velocity field was presented to observe effect of the baffles on sloshing with the aid of ADINA and laboratory experiments conducted on a hexapod motion platform.

To study the flexural behavior of prestressed concrete beams with high-strength steel reinforcement and high-strength concrete and improve the crack width calculation method for flexural components with such reinforcement and concrete, 12 specimens were tested under static loading. The failure modes, flexural strength, ductility, and crack width of the specimens were analyzed. The results show that the failure mode of the test beams was similar to that of the beams with normal reinforced concrete. A brittle failure did not occur in the specimens. To further understand the working mechanism, the results of other experimental studies were collected and discussed. The results show that the normalized reinforcement ratio has a greater effect on the ductility than the concrete strength. The cracking- and peak-moment formulas in the code for the design of concrete (GB 50010-2010) applied to the beams were both found to be acceptable. However, the calculation results of the maximum crack width following GB 50010-2010 and EN 1992-1-1:2004 were considerably conservative. In the context of GB 50010-2010, a revised formula for the crack width is proposed with modifications to two major factors: the average crack spacing and an amplification coefficient of the maximum crack width to the average spacing. The mean value of the ratio of the maximum crack width among the 12 test results and the relative calculation results from the revised formula is 1.017, which is better than the calculation result from GB 50010-2010. Therefore, the new formula calculates the crack width more accurately in high-strength concrete and high-strength steel reinforcement members. Finally, finite element models were established using ADINA software and validated based on the test results. This study provides an important reference for the development of high-strength concrete and high-strength steel reinforcement structures.

A three-dimensional multitransmitting formula is developed in ADINA to simulate the input of seismic waves and the scattering of infinite domains at the same time, consistent with the progress of the explicit finite element method of lumped mass. A three-dimensional cube model is built, and a delta pulse wave is input to compare the simulation results with the analytical solutions. The simulation results show that the peak error is 0.2% of the input wave, which meets the requirements of the usual numerical simulation. This method has a certain efficiency advantage in site effect analyses of fine models for localized fields. A velocity structure model of the Yuxi Basin is built, and the associated basin effect is studied by numerical simulation. The distribution of the focusing effect is related to the structure of the narrow east-west and wide north-south features in the Yuxi Basin, and the edge effect is related to the slope of the basin base. A distribution map is given of the amplification effect of ground motion in the basin.

The dynamic characteristics and liquid sloshing of a circular tank are analysed using ADINA software through seismic response analyses. The maximum sloshing wave height for the circular tank under unidirectional horizontal seismic action is developed. The calculation method involves three parameters such as tank radius, seismic coefficient and dynamic coefficient. The dynamic coefficient of liquid sloshing is determined corresponding to the long-period seismic design β spectrum with a 5% damping ratio using basic sloshing period. The established method can guide the seismic design of liquid-containing structures. The established method of calculating sloshing wave height is compared with those in the American code.

This paper deals with free vibrations of the axially functionally graded (AFG) horseshoe arch. The modulus of elasticity and the mass density of AFG material of arch are chosen as a univariate quadratic function. The differential equations with the boundary conditions that govern the free vibration of such arch are derived and numerically solved to calculate natural frequencies and mode shapes. Natural frequencies of this study agree well with those of the finite element ADINA. Parametric studies of the geometrical and mechanical properties of the arch on frequencies and mode shapes are performed and extensively discussed.

This paper presents a comparative analysis with different models of the flexspline for a harmonic hermetic drive. The flexspline is thin-walled construction, deforming during work, so its design is a very complicated process. The paper contains a strength analysis for some selected models of this gear. Calculations were performed using the MES method in ADINA. The work presents stress diagrams in longitudinal intersections for susceptible wheels of different shapes, for direct comparison. Suggested changes in construction of flexspline will increase the durability of the welded hermetic gear.

The fatigue life prediction method using numerical analysis is the latest evaluation technology to predict the fatigue life using the stress data obtained from the structural analysis in order to reduce the evaluation time and cost. A rolling mill is a machine that produces a coil by rolling the material by a roller and the spindle of the rolling mill device serves to transmit the power to the rollers by periodically rotating by the motor. These spindles consist of universal joints, shafts and bearings to deliver power to the rollers. The spindle of the rolling mill is always exposed to the environment subjected to the fatigue load due to the rotation moment by the periodic rotation and there is possibility of the breakage accident due to this. It is very important to prevent breakage by predicting the fatigue life of the spindle in a dynamic operating environment. Therefore, in this study, dynamic stress analysis is performed considering the actual rotating environment conditions using ADINA. Based on the results of stress analysis, we want to predict fatigue life considering dynamic operating environment using WINLIFE that is used for the evaluation of the fatigue life of single shafts, multi-shafts, and gear bearings. Fatigue life analysis of the spindle of the rolling mill using linear cumulative damage theory using S-N curve and equivalent stress was performed in order to evaluate the fatigue life. Stress-life fatigue theory is a method of calculating the lifetime by the minimum input showing the fatigue characteristics of the material.

From the point of view of bridge structures, the moving load is one of the most important components of the load. The analysis of the influence of moving load on bridges is carried out numerically or experimentally and can be traced in the literature since the year 1849. The first impulse was the collapse of the Chester Rail Bridge in England in the year 1847. The present paper analyses the effect of the moving load on a two-span bridge, both numerical and experimental way. The planar model of the vehicle and the bridge is adopted. The bridge is modeled as Bernoulli-Euler beam. The heavy vehicle is modeled as a discrete computational model with 8 degrees of freedom. Two approaches are used in numerical modeling. For the first time, the task is solved by the finite element method in the environment of the program system ADINA. The Newmark's method is used for the solution of equations of motion. The classic approach is used for the second time. A discrete computational model of a bridge with two degrees of freedom is used. Equations of motion are solved numerically in the environment of program system MATLAB by the Runge-Kutta 4th order method. The influence of vehicle speed on vertical deflections in the middle of individual bridge fields is analyzed in the speed range from 0 to 130 km/h with a step of 5 km/h. The detailed comparison of both numerical approaches is made at a vehicle speed of 70 km/h. The deflections of the bridge and the deflection of the vehicle are compared with each other. The correctness of the assumptions used in the numerical solutions was verified by measurement on a model beam in the laboratory. The results of the experimental tests were compared with the results of the numerical solution.

Abdominal aortic aneurysm (AAA) is a critical health disorder, where the abdominal aorta dilates more than 50% of its normal diameter. Enlargement in abdominal aorta alters the hemodynamics and flow-induced forces on the AAA wall. Depending on the flow conditions, the hemodynamic forces on the wall may result in excessive mechanical stresses that lead to AAA rupture. The risk of rupture can be predicted using advanced computational techniques such as computational fluid dynamics (CFD) and fluid–structure interaction (FSI). For a reliable rupture risk assessment, formation of intraluminal thrombus (ILT) and uncertainty in arterial material properties should be taken into account, mainly due to the patient-specific differences and unknowns in AAAs. In this study, AAA models are computationally investigated by performing CFD simulations combined with FSI analysis. Various levels of ILT burdens are artificially generated in a realistic AAA geometry, and the peak effective stresses are evaluated to elucidate the effect of material models and ILT formation. The results indicate that increasing the ILT burden leads to lowered effective stresses on the AAA wall. The material properties of the artery and ILT are also effective on the stresses; however, these effects are limited compared to the effect of ILT volume in the AAA sac.

The volume “Building bridges: Promoting wellbeing for family. Handbook for parents ”, published by Lumen Publishing House from Iași in 2018, was developed within the project “Building bridges: Promoting social inclusion and well-being for the families of children with special needs (PSI-WELL)”, and is the result of a cross-sectional and transnational study on social inclusion, stress levels and the well-being of families with children with special needs, carried out in each of the 6 countries that were partners in the project (Romania, Spain, Portugal, Croatia, Turkey and Lithuania). The volume coordinated by Assoc. Prof. PhD. Aurora Adina Colomeischi provides concrete results of the extensive research undertaken within the project and seems to be a viable starting point for the development of an educational policy for parents and families of children with special needs. The work is very well substantiated scientifically, and is especially useful for parents who face the special needs of their children, but also for the specialists who undergo therapy with them. In our opinion, the book deals with desirable aspects in the development of social intervention programs often aimed at parents with children with special needs, programs dealing with improving personal resources and parenting skills needed to solve various special and difficult situations presented by children.

A novel hollow type of traveling wave rotary ultrasonic motor is proposed, optimized, fabricated, and tested in this study. Unlike conventional ultrasonic motors, this novel ultrasonic motor adopts a bran-new preloading method that preload is applied from the bottom of the stator through a wave spring, which can not only enhance the anti-overload ability but also extend the working life of the motor. According to this motor, a three-dimensional finite element model has been built by the commercial finite element software ADINA. In terms of the friction material and the preload, a detailed further optimization procedure is given after the initial design. Finally, the appropriate size and location of the friction layer and a proper preload for this motor have been determined. Almost all of the motor’s mechanical capacities, such as rotational speed, torque, and deformation, can be obtained by simulations in ADINA, which have good agreement with experimental results.

In this study, through a vibration table test, finite element simulation, and research on the rationality of the wave-height fortification of national storage tank specifications, the sloshing response of vertical storage tanks under the action of near-fault ground motion was analyzed. The test results showed that the sloshing wave height of a vertical storage tank was larger under near-fault or long-period ground motions, and the relationship between the sloshing wave height and the peak acceleration of input ground motions was approximately linear. The numerical simulations of the model tank showed that the simulation wave height and the test wave-height data were well fitted. Therefore, it was feasible to simulate the sloshing of large vertical storage tanks using ADINA software. In addition, a large number of sloshing simulations of near-fault ground motions on 10,000 m3vertical storage tanks were performed. The simulated wave height had a high correlation with the predominant period or pulse period of near-fault ground motions. Under the calculation with similar parameters, the wave height of the tank standard in several countries had a lower fortification of the near-fault excitation wave height. Through the root mean-square method using a small sample size, a wave-height correction under a near-fault effect was applied to the wave-height formula for the Chinese tank seismic specification. Finally, the problem of a double-damping correction was addressed by adjusting China’s GB50341 wave-height formula. This work provides a reference value for practical engineering applications.

Review

Detonation is a specific type of a rapid exothermic reaction, which always involves a detonation wave (in the explosive) and the shock wave (in the environment). Modelling of the pressure wave falls in the fluid flow and interference with obstacles in the flow. The purpose of this paper is to development of simulation model based on the finite element method (FEM) for shock wave propagation in air form the explosion of a spherical charge from TriNitroToluene (TNT) material. The air is the classical ideal gas and explosive material TNT is defined using Jones-Wilkins-Lee (JWL) equation. The computational model is 2D-dimensional model with four node axisymmetric elements. The effect of the explosion on the pressure distribution in the air and rigid surface (ground) is investigated. Numerical solution of the dynamic response was performed using commercial FEM software ADINA.

This paper presents a unified model to analyze the free vibration and buckling of axially functionally graded Euler-Bernoulli columns subjected to an axial compressive force. The material properties vary linearly along the longitudinal direction, and column with circular and square cross sections is linearly tapered. The governing differential equations of the problem are derived and solved using the direct integral method combined with the determinant search technique. The computed results are compared with those reported in the literature and obtained from the finite element software ADINA. Numerical examples for natural frequency, buckling load and their corresponding mode shapes are given to highlight the effects of modular ratio, taper ratio and cross sectional shape as well as the end condition.

Natural gas vehicles use natural gas as a raw material; thus, compared to conventional diesel vehicles, there is no soot or fine dust produced, the noise generated is half, and the amount of air pollution is one tenth. Despite a considerable increase in their demand, there is still much controversy in terms of their safety, and safety-related accidents have frequently occurred in recent years. According to reports, most compressed natural gas (CNG) bus accidents are caused by the rupture of the pressure vessel, and the reason for this accident is that the containers show a high number of manufacturing defects. In the case of a metallic liner, the mechanical properties and rupture characteristics of the pressure vessel vary greatly depending on the method and conditions of the heat treatment process. Several accidents where pressure vessels have ruptured have been reported, and all these ruptures occurred owing to brittle fracture of the container because the mechanical properties, such as the tensile strength and the fatigue strength of the CNG vessel changed in comparison with the normal vessel owing to poor heat treatment processes. In this study, we compared and analyzed the structural integrity and fatigue characteristics of the normal vessel and the poorly heat-treated vessel under charging conditions and under an atmospheric environment, where the vessel is mounted on an actual CNG bus. This comparison is made through a heat convection and conduction analysis using SINDA/FLUENT and a structure and fatigue analysis using ADINA and winLIFE.

The stress distribution in specimens designed for the tensile testing is evaluated in the article. The reinforcement consists of long fibers that copy the outer contour of the specimen. The fibers are inserted within the curvature at the edge of the specimen with the neck. The stress distribution in fibers and matrix of dogbone specimen and specimen of rectangular shape is analyzed and compared. The analysis of stress state is analyzed in FEM software ADINA. Long fibers deposited in specimen were modeled using rebar elements.

Continuous fiber fabrication technology, developed by Markforged and used in MarkTwo printers, allows using of reinforcing fibers, which improve mechanical properties of produced parts. The technology enables choosing of two fiber deposition strategies: isotropic fiber fill and concentric fiber fill. With the isotropic fiber fill, there is an option to set up various fiber angles in each layer. The article is focused on stress distribution analysis using FEM in a matrix and individual reinforcing fibers of specimens loaded to uniaxial tension. Main observed parameters are stresses in matrix and fiber and usage of the reinforcing material.

[EN] Sheet metal forming is a very important process in industry to create a wide variety of goods. The analysis of local ductility and residual stresses is important both to assess the viability of the manufacturing process and the reliability of the resulting elements in service. An example is crash-worthiness, where remaining ductility and residual stresses govern the safety of the overall structure during the impact. A main ingredient of finite element simulations for sheet metal forming in industry is a robust continuum-based computational algorithm for large strain elastoplasticity which includes both elastic and plastic anisotropy, as well as mixed hardening. The theory should use exactly-integrable (conservative) elastic and hardening behaviors based on physically motivated proper state variables and, if possible, result in a simple integration algorithm. In this work we implement a novel large strain formulation for anisotropic hyperelasto-plasticity in a user subroutine of the commercial program ADINA to perform sheet metal forming simulations, testing the robustness and suitability of the model for industry, as well as its accuracy. The formulation is based on a new approach to the treatment of large strain kinematics, using logarithmic elastic corrector rates instead of plastic rates. Furthermore, kinematic hardening is formulated without an explicit backstress. We compare and discuss the results with those in the literature which use alternative frameworks., Partial financial support for this work has been given by grant PGC 2018-097257-B-C32 from the Direccion General de proyectos de Investigacion of the Ministerio de Economia y Competividad of Spain. The ADINA program license used in this work has been a courtesy of ADINA R&D to the UPM

Sheet pile quay walls have widely been used in port engineering, hydraulic engineering, and civil engineering, but the sheet pile quay is a flexible retaining structure, which undergoes large deformation during earthquakes. The seismic design methods of the sheet pile quay wall in different countries are greatly different, and there is deficit of studies performed on the seismic residual displacement of the sheet pile quay walls. Based on the pseudostatic method and the calculation method for obtaining the dynamic earth pressure of clay soil, it is assumed that the cantilever part of the sheet pile quay wall bears the dynamic active earth pressure and the part in deep soil bears dynamic passive earth pressure on the side of the sea and bears dynamic active earth pressure on the side of the ground. The hydrodynamic pressure acting in front of the wall is calculated using Westergaard’s approach. The displacement of the front wall of the sheet pile quay is calculated, respectively, according to the upper part and lower part of mud surface. Based on the deflection curve differential equation and boundary conditions, the calculating formulas on seismic residual displacements of the sheet pile quay walls are derived and the proportional displacement method for determining the tension force of the pull rod is given. Combining with an engineering case, the theoretical calculation results are compared with the ADINA simulation results, and comparison results show that these two calculation methods are close under the mud, but they have little difference in the calculation results of the part above the mud because of the proportional displacement method of the tension force of the pull rod.

Considering that the subway tunnelling projects in the Chongqing region are located in strata dominated by sandstone and mudstone, the main empirical construction parameters (excavation thrust = 5 880 ∼ 6 860 kN, average pea gravel content (APC) ≥ 85%, and grouting pressure (GP) = 0.3 MPa) were obtained by engineering surveys; these empirical parameters were similar to those optimized under interval tunnel construction conditions. Additionally, a simulation method was developed based on the construction characteristics of a single shield TBM by using the ADINA software to simulate the construction process of subway tunnels undercrossing the pile foundations (end-bearing piles) of an old surface building in the composite strata of the Chongqing Rail Transit Loop Line. A sensitivity analysis was performed on the calculation parameters first because the changes in the stratigraphic and TBM construction parameters greatly influenced the calculation results. Then, we used the modified calculation parameters to study the effects of tunnel construction on the settlements of the ground surface and pile foundations in the composite strata, and these effects were compared to the field monitoring results. The results showed good agreement between the numerical calculations and the monitoring findings. Thus, the methodology and empirical construction parameters adopted in this paper can provide a reference for the construction of other tunnel sections of this project in similar construction conditions.

The problem of simulation of moving load effect on bridges is a relatively old problem. It was induced by the collapse of the Chester Rail Bridge in England in the year 1847 and can be traced in the literature since the year 1849. The new generation of young research workers is capable to contribute to the solution of the problem with new findings. The contribution is devoted to the modeling of the vehicle motion along a two-span bridge in the environment of the program system ADINA. The task is solved as a plane problem. It described the creation of a discrete computational model of vehicle with 8 degrees of freedom. The bridge is modeled using beam elements. It is assumed that the vehicle enters the bridge already vibrant. The vehicle and bridge response is modeled when vehicle driving at the speed of 70 km/h. The time course of oscillation of vehicle model's characteristic points and the oscillation of mid spans of individual bridge fields are shown graphically. Important results are given in numerical form. The Newmark's method is used for the solution of equations of motion.

To evaluate the response and output performance of an assembled and complete ultrasonic motor, a 3D finite element model has been proposed by a commercial finite element software ADINA. The simulated results of the output performance can be obtained, which are in good agreement with the available experimental data. Therefore, it is convenient to know the mechanical capacity of the motor before prototype manufacture. Moreover, the radial, circumferential and axial displacements of the contact nodes are acquired to simulate the real elliptical motions of the stator. Without assuming that the rotor behaves as a rigid body, the actual contact mechanism between the stator and rotor is reflected accurately. The simulation shows the distinct stress concentration issue of the motor, which can facilitate the stress analyses to avoid the failure of the motor. This study provides a powerful tool for the structure design and performance prediction of the ultrasonic motor.

Mitochondrial DNA cytochrome oxidase (COI) and microsatellite DNA loci were used to better explain the speciation events, history of hybridization, and genetic population structure of the stone crabs Menippe adinaWilliams & Felder, 1986 and M. mercenaria (Say, 1817–1818). A survey of a 670-bp COI sequence of 711 stone crabs collected from Texas to North Carolina and from Belize, Central America showed the presence of two well-defined mtDNA lineages, Lin-A and Lin-B. Based on molecular clock calibrations of a published study these lineages shared a common ancestor between 1.5 to 1.8 million years. Lin-A was evident throughout the range of the two Menippe species, but Lin-B was found only in the eastern Gulf of Mexico and does not represent any of the two species. Our findings refute the claim that the eastern Gulf hybrid zone is the product of hybridization between M. adina and M. mercenaria. We propose that the hybrid zone is instead a relic of introgressive hybridization between the M. mercenaria of eastern Gulf stone crab nDNA Lin-AA that carries Lin-A and the new nDNA Lin-BB that carries Lin-B, forming the hybrid nDNA Lin-AB. Lin-B emerged from a founder effect in the Okefenokee Trough and introgressed into the eastern Gulf. There is no Lin-B in the Atlantic, hence no hybridization in that region. Using stone crab-specific microsatellite markers we found no evidence of an ongoing hybridization in the eastern Gulf and this region cannot be called a hybrid zone since hybridization here ceased probably soon after the last glacial episode. The microsatellite-marker analyses also suggested that the stone crab was geographically divided into four genetic clusters by three barriers to gene flow, the strongest of which is the one between the two species, M. adina and M. mercenaria, around Cape San Blas, Apalachicola Bay, Florida.

45 p. : il. -- Bibliogr.: p. 32-36 [EUS] Lan honen helburua, nagusiki, Lehen Hezkuntzako ikasleen autokontzeptuan sexuaren eta adinaren arabera egon daitezkeen aldeak aztertzea izan da. Ebaluatutako lagina Amurrioko Lucas Rey HLHIko Lehen Hezkuntzako 7 eta 13 urte bitarteko 100 ikaslekoa izan da. Horietatik 46 (%46) lehen ziklokoak dira eta 54 (%54) bigarren ziklokoak, horien artean 49 (%49) neskak eta 51 (% 51) mutilak. Ikasle hauen autokontzeptua neurtzeko Piers Harrisen inkesta erabili da. Inkesta honek ikasleek beren buruaz duten pertzepzioari buruzko informazioa lortzeko aukera ematen du (autokontzeptu globala), bai eta autokontzeptuak barne hartzen dituen alderdiei buruzkoa ere, 6 dimentsioen bidez (izendatu dimentsio horiek). Lortutako datuek ez dute autokontzeptuaren dimentsioetan sexuaren araberako alde esanguratsurik adierazten. Aldiz, adinari dagokionez, lortutako emaitzek adierazten dute ikasle zaharrenek estatistikoki puntuazio hobeak lortzen dituztela autokontzeptu konduktualean, sozialean eta zoriontasun-asebetetzean. Hobekuntza proposamena bezala, autokontzeptu sozialaren garapen positiboa lantzeko. Lehen Hezkuntzako 3. eta 4. mailako ikasleei zuzendutako esku-hartze proposamen bat aurkezten da. Autokontzeptuaren dimentsio soziala hobetzeko, 5 jarduera proposatzen dira, eta horietan gizarte-trebetasunak landuko dira; izan ere, trebetasun horiek funtsezkoak dira beste pertsona batzuekin harremanetan jartzeko edo gizarte-eremuan behar bezala moldatzeko. [ES] El objetivo de este trabajo ha sido principalmente analizar las posibles diferencias en el autoconcepto del alumnado de Educación Primaria en función del sexo y la edad. La muestra evaluada ha sido de 100 alumnos de 7 a 13 años del CEIP Lucas Rey HLHI de Amurrio. De los cuales 46 (46%) son de primer ciclo y 54 (54%) son de segundo ciclo, entre ellos 49 (49%) son niñas y 51 (51%) son niños. Para medir el autoconcepto de estos alumnos se ha utilizado la encuesta de Piers Harris. Esta encuesta permite obtener información sobre la percepción del alumno (autoconcepto global) y sobre los aspectos que incluye el autoconcepto a través de 6 dimensiones. Los datos obtenidos no muestran diferencias significativas según el sexo en las dimensiones del autoconcepto. Por el contrario, en cuanto a la edad, los resultados obtenidos indican que el alumnado de mayor edad obtiene mejor puntuación estadísticamente en autoconcepto conductual, social y satisfacción de felicidad. Como una propuesta de mejora, para trabajar el desarrollo positivo del autoconcepto social. Se presenta una propuesta de intervención dirigida al alumnado de 3º y 4º de Educación Primaria. Para mejorar la dimensión social del autoconcepto se proponen 5 actividades en las que se trabajarán habilidades sociales; ya que son fundamentales para relacionarse con otras personas o desenvolverse adecuadamente en el ámbito social. [EN] The aim of this work has been mainly to analyse possible differences in the self-concept of primary school pupils according to sex and age. The evaluated sample has been 100 students from 7 to 13 years old from CEIP Lucas Rey HLHI in Amurrio. From these, 46 (46%) are in the first cycle and 54 (54%) are in the second cycle, including 49 (49%) girls and 51 (51%) boys. The Piers Harris survey was used to measure the self-concept of these pupils. This survey allows us to obtain information on the student's perception (global self-concept) and on the aspects included in the self-concept through 6 dimensions. The data obtained does not show significant differences according to sex in the dimensions of self-concept. On the contrary, in terms of age, the results obtained indicate that the older students obtain a statistically better score in behavioural and social self-concept and happiness satisfaction. As a proposal of improvement, to work the positive development of the social self-concept. A proposal of intervention directed to the students of 3rd and 4th grade of Primary Education is presented. In order to improve the social dimension of the self-concept, 5 activities are proposed in which social skills will be worked; since they are fundamental to relate to other people or to develop adequately in the social field.

Shallow foundations resting on a deep layer of soft saturated clay are considered a geotechnical challenge. The design engineer is faced with challenges in selecting safe and economic solutions for the foundations of these light weight structures by turning to the shell-shaped foundations to deal with such foundation problems and avoid the use of the costly deep foundations or other soil improvement schemes. This paper introduces different bottom of foundations shapes resting on extended soft clay layer in an effort to minimize the soil stresses and reduce the settlements. Elliptical, trapezoidal and inverted folded footings have been used as an alternative to the conventional flat bottom shallow footings. The purpose of the current study is to reach the optimal shape of the foundations, which achieves reduced stresses, reduced settlements and consequently cost. The geotechnical behavior of different bottom of foundation shapes resting on saturated soft clay is investigated experimentally and numerically. The experimental investigation started with studying a model for the conventional square flat footing shape resting over saturated soft clay. Elliptical, trapezoidal and inverted folded bottom of foundation models are tested and compared with the reference conventional square flat ones. In addition to the experimental study, a numerical analysis is performed using the finite element software ADINA. Verification of the numerical model is conducted first against the experimental results for all the studied cases. The verified numerical model is then extended to cover full-scale footing sizes of conventional and other studied footing cases and shapes. The optimum bottom of foundation shape is the one that gives the lowest soil stresses and consequently the lowest settlements.

Design scheme of steel shell flow tube in the inflow and outflow passage of the vertical axial pumping stations takes advantages of conventional concrete scheme in simple construction and convenient installation of the pump. A three-dimensional pumping station model was established based on fluid-structure interaction method in ADINA. Typical measure points were selected to analyze the features of the unsteady turbulent flow in fluid zone and vibration responses of the steel shell tube in solid zone. Time and frequency domain investigation of fluid domain revealed the transmission path of pressure pulsation, that was the pulsation transferred from the pump to the inlet and outlet respectively with amplitudes sharply decreasing, which verified the rationality of calculation and established the basis on structure analysis. Dynamic displacement, velocity and acceleration analysis of measure points in steel shell tube showed that top shell domain near the inlet of steel shell flow tube had obvious vibration amplitude, which required great attention. The first main frequency equaled the rotational frequency of the blade, indicating one of the most important vibration sources in the pump was the pressure pulsation induced by blade rotation. The design scheme of steel shell flow tube is practical and could be promoted to other similar pumping stations because the vibration amplitude is much lower than the regularity. This research provides great importance to the design and application of the steel shell flow tube in pumping stations.

The effects of seawater and site conditions on the seismic response of the isolated continuous girder bridge are evaluated in this study. The seawater-muddy soil-isolated bridge coupling model is built in the dynamic analysis software ADINA, and the external seismic wave input is realized by the seismic wave motion analysis program. The influences of seawater and muddy soil on the seismic response of isolated continuous girder bridges are determined by comparing different offshore site models. The results indicated that the seawater and the muddy soil magnify the displacement of the seabed. The existence of seawater increases the longitudinal relative displacement of piers by 20%–40% but has limited influence on the bending moment and shear force of piers. The muddy soil can increase the longitudinal relative displacement and internal force of the piers remarkably. Moreover, the displacement of bridge bearings increases significantly under the combined influence of muddy soil and seawater. In the seawater-muddy soil-isolated bridge coupling model, the seawater and site condition can influence the seismic performance of sea-crossing bridges obviously.

Mitral insufficiency is the first valvular disease worldwide, with a 2% prevalence. When open-heartsurgery is impossible for the patient, surgeons use percutaneous devices to help the mitral leaflets coapt. However, the only device currently available is based on the edge-to-edge mitral valve repair technique. This type of implant is not adapted for patients suffering from functional mitral insufficiency, where the ventricle is responsible for the lack of coaptation of the leaflets. This thesis aims to provide a numerical platform to help the development of a mitral valve implant adapted for those patients. Several mitral valve geometries were created from a parametric model using anatomical measurements. Finite element simulations of the mitral valve were performed using ADINA to determine the valve closure under constant pressure. Several material models were developed in large strain and large deformation to model the valve closure accurately. Pathological behaviour such as annulus dilatation and chordae rupture were modelled, and several methods were tested to implement medical devices. Fluid-structure interaction of a 2D mitral valve was obtained using an ALE description and a monolithic coupling approach. Both the systole and the diastole were reproduced and studied, and the hermetic seal of the valve was detailed. The numerical platform developed is suited to model mitral valve function and can be used to help the development of mitral implants. In addition, the parametric geometry model and the anisotropic material model will be useful to depict with realism the valve function. A 3D fluid-structure interaction of the mitral valve could be developed., L’insuffisance mitrale est la valvulopathie mondiale la plus fréquente avec une prévalence de 2%. Lorsque le patient n’est pas en mesure d’être opéré à cœur ouvert, un implant percutané est utilisé pour aider la fermeture des feuillets. Le seul implant actuellement disponible est basé sur la réparation bord à bord de la valve mitrale. Il réduit le reflux vers l’oreillette lors de la systole, mais n’est pas adapté pour les patients souffrant d’insuffisance mitrale fonctionnelle, chez qui la pathologie provient du ventricule et non des éléments de la valve. L’objectif de la thèse est de fournir une plateforme numérique permettant d’aider au développement d’un implant adapté pour ces patients. Plusieurs géométries de valve ont été réalisées au moyen d’un modèle paramétrique, en utilisant des données anatomiques. La dynamique de la valve a été modélisée avec le logiciel ADINA par des simulations éléments finis en grandes déformations. Des modèles structurels de la valve ont permis de représenter la fermeture de la valve sous une pression uniforme. Les lois de comportement de matériaux ont été développé dans le but d’obtenir une fermeture réaliste de la valve. Cela a nécessité la prise en compte de l’hyperélasticité et de l’anisotropie des tissus. Des pathologies valvulaires, telles que la dilatation de l’anneau mitrale ou la rupture des cordages tendineux ont été modélisées, et plusieurs méthodes ont été testées pour y apposer des systèmes médicaux. En utilisant une description ALE et un couplage monolithique, les interactions fluide-structure ont été simulées pour une valve mitrale bi-dimensionnelle. La fermeture hermétique de la valve pendant la systole a pu être reproduite et l’ouverture de la valve étudiée pendant la diastole. La plateforme numérique développée permet de modéliser la fonction de la valve mitrale et peut être utilisée pour aider au développement d’un implant mitral grâce au modèle paramétrique reproduisant différentes géométries de valve et aux lois matériaux anisotropes. Une perspective reste la création d’un modèle 3D des interactions fluide-structure de la valve mitrale.

In the deep sea mining system, the lifting pipe is a special articulated cantilever pipe, which is prone to large deviations and bending deformations. The finite element plane beam element idea is used to discretize the dynamic differential equation of the lifting pipe, and the vibration balance equation of the lifting pipe affected by internal flow is established. Through the computer simulation software ADINA, the model of lifting pipe and internal flow is established, and the computer simulation process is determined. The computer simulation results show that under different working conditions, the maximum stress of the lifting pipe acts on the top of the lifting pipe, and the maximum offset occurs at the bottom of the lifting pipe. When the internal flow is considered in the lifting pipe, the maximum stress at the top of the pipe increases gradually and the maximum lateral displacement at the bottom of the pipe increases gradually with the increase of the internal flow velocity.

This work focuses on subcooled boiling heat transfer during flow in a minichannel heat sink with three or five minichannels of 1 mm depth. The heated element for FC-72 flowing along the minichannels was a thin foil of which temperature on the outer surface was measured due to the infrared thermography. The test section was oriented vertically or horizontally. A steady state heat transfer process and a laminar, incompressible flow of the fluid in a central minichannel were assumed. The heat transfer problem was described by the energy equations with an appropriate system of boundary conditions. Several mathematical methods were applied to solve the heat transfer problem with the Robin condition to determine the local heat transfer coefficients at the fluid/heated foil interface. Besides the 1D approach as a simple analytical method, a more sophisticated 2D approach was proposed with solutions by the Trefftz functions and ADINA software. Finite element method (FEM) calculations were conducted to find the temperature field in the flowing fluid and in the heated wall. The results were illustrated by graphs of local heated foil temperature and transfer coefficients as a function of the distance from the minichannel inlet. Temperature distributions in the heater and the fluid obtained from the FEM computations carried out by ADINA software were also shown. Similar values of the heat transfer coefficient were obtained in both the FEM calculations and the 1D approach. Example boiling curves indicating nucleation hysteresis are shown and discussed.

This article is divided into two parts&mdash, in the first part, authors inform about their testing device that enables the acquisition of results from uniaxial and multiaxial fatigue tests (the bending&minus, torsion combination). We present the approaches used during designing and building the testing device. The direct implementation of the research in the second part will concentrate on implementing the acquired results for the frame design of a vehicle worked out by the authors. The three-wheeled vehicle has the front steered wheel suspended in an unconventional way. This original design can cause an increased load on the vehicle&rsquo, s frame. This can be apparent mainly during driving through curves. Therefore, the fatigue curves of the tested material (EN AW 6063) will be implemented from the point of view of its usability in operation. A vehicle frame is most often loaded by bending and torsion. The authors assess the influence of welding on the fatigue life of this unique unconventional vehicle by determining the fatigue curves of the material for its production. The stresses achieved on the test specimens fully correspond to the load of the frame (in welds) during its operation.

Metode strut-and-tie model merupakan metode perencanaan struktur yang didasarkan padapemahaman tentang adanya daerah D dan daerah B pada struktur beton bertulang. Untuk itu, metodestrut-and-tie model dirintis oleh penelitian yang dilakukan oleh Schlaich [Schlaich et al., 1987] diUni-Stuttgart, Jerman. Selanjutnya berkembang pesat [Adebar et al., 1990; Jirsa et al., 1991; Reineck,1996, 1999, 2002; ACI 318R, 2002, 2005, 2008]. Tujuan penelitian ini adalah mempelajari metodestrut-and-tie model untuk perencanaan balok tinggi beton bertulang, mempelajari simulasi numerikmodel benda uji dengan menggunakan metode elemen hingga dengan ADINA untuk mendapatkanparameter yang diperlukan dalam perencanaan metode strut-and-tie model. Model benda uji dalampenelitian ini diambil dari hasil penelitian eksperimental balok tinggi Hardjasaputra [Hardjasaputra,2006]. Hasil penelitian memperlihatkan bahwa perbedaan %_relatif lendutan balok hasil simulasiADINA terhadap eksperimental berkisar antara 25,49%-27,71%. Perbedaan %_relatif regangan-z hasilsimulasi ADINA terhadap eksperimental berkisar antara 10,53%-17,25%. Penentuan nilai

Fiber reinforced composites have significant usage in aircraft and automotive industries due to their advantages like high strength to weight and stiffness to weight ratios. Short manufacturing cycle time and low production cost are reasons of continued development of additive manufacturing. 3D printing allows to produce reinforced composites but there is necessity to improve printing parameters and propose appropriate fiber deposition with aim to gain suitable mechanical properties. Article is focused on assessment of different options of creating long fibre composite models for 3D printing. These models are reinforced using long aramid, carbon and glass fibres. The goal of paper is analyzing of geometry constraints of fiber adding into structure. In addition, the alternative ways of modelling in FEM software ADINA will be presented.

The main scientific goal of the article is to modernize the methods of designing the rotating mechanisms of working machines (excavators, cranes, backhoe loaders, loaders) and other devices (wind turbines, radars, radio telescopes, drilling machines, wastewater treatment plants) in which the construction of the rotate node uses slewing bearings. In this article, the research will focus on how to mount the bearing to the machine. The calculations will be carried out by numerical modelling of bearings and support structures of machines using the finite element method with the wide use of non-linear FEM techniques and taking into account the elastic-plastic state of deformation in the contact zone. In the research, the ADINA program will be used as the basic numerical calculation tool.

The paper is focused to size and shape influence analysis of inner structures to mechanical properties of the construction created by 3D printing. Analysis is solving in finite element method software ADINA. Foundation of the analysis is a specimen, where have same dimensions and boundary conditions. Boundary conditions replace tensile test with loading 1000N. Aim of the research is to get results (size and shape of the inner structure) of the specimen by tensile test. In results will be outputs (mechanical properties - stress, strain) compared among each other and used next calculations and optimization. Knowledge of these properties is very important in the production of Onyx-based components for the automotive and aerospace industries.

Liquid sloshing is a problem of serious concern in partially liquid filled containers mounted in the moving vehicle or structure. An analytical technology is developed to solve the dynamic response of the liquid in the circular cylindrical container with multiple rigid baffles subjected to the pitching excitation. The generalized coordinates are introduced to expand the free surface elevation and the velocity potential, which contains the Stokes-Joukowski potential. Based on the partition of the liquid domain, a new method is developed to obtain the analytical solution of the Stokes-Joukowski potential. According to the kinematic and dynamic boundary conditions on the free surface, the dynamic response equation can be established. The analytical model for liquid sloshing is validated with the numerical results obtained from the commercial software ADINA. Systematic parametric investigations are carried out to reveal the effects of baffles’ parameters and the pitching excitation frequency on the responses of the liquid.

The book Difference Equations, Discrete Dynamical Systems and Applications, edited by Saber Elaydi, Christian Potzsche and Adina Luminiţa Sasu, represents selected contributions from the 23rd Inter...

The submitted paper is devoted to the numerical modeling of the dynamic effects of moving vehicles on concrete pavements. The finite element method, namely the ADINA program, is used to model the problem. To solve the task, it is necessary to create a vehicle and a road computational models. The vehicle model is spacious and corresponds to a heavy truck of the Tatra type. The so-called single-layer road model on an elastic Winkler foundation is used. Concrete pavements are modeled using shell or solid elements. The output of the solution is the time course of the dynamic deflections at the individual points of the slab and internal forces and the stress states in the concrete slab at the individual time points of the solution. The calculation results for each computational model are compared to each other.

Aiming at solving the problem of low unloading sensitivity, bad dynamic performance and poor stability of high-pressure and large-flow relief valve in hydraulic support system, a new differential type of high-pressure and large-flow relief valve, functioned by high water-based hydraulic medium, is designed. Through analysing the influence of spool form, elastic element, and working principle on valve performance, a structural scheme of large-flow and high-pressure safety valve is put forward. The three-dimensional fluid–solid coupling model of differential safety valve is established; through ADINA software, three-dimensional fluid–solid coupling simulation of relief valve's orifice from shutdown to full opening is carried out to analyse the distribution of internal pressure in the flow field of the safety valve and the pressure change of the structure field. The physical simulation model of safety valve is established by using AMESim software, and the dynamic performance of safety valve is simulated under the given signal of nominal flow and small flow. According to the design structure, the safety valve with the rated flow of 3000 L/min is manufactured and tested. The simulation and experimental results show that the safety valve has good dynamic performance and high sensitivity..

The aim of the work was numerical analyses of a steel-concrete composite column and a steel column. An internal column 3.60 m in length was considered. The column was on the second storey of a six-storey building designed for retail and services. The column was subjected to compression and uniaxial bending. The existing steel column was made from a welded H-profile. In the first stage of the work, the composite column was designed as an alternative to the existing steel column using the analytical method. A steel reinforced concrete column with a steel H-profile was selected. The second part of the work consisted in modelling the steel and composite columns. The geometries, loads and boundary conditions used in simulations of the columns were the same as in the analytical calculations. Numerical analysis was carried out using the ADINA System based on the finite element method. In the steel column, the stresses and displacements were considered. In the composite column, the stresses in the steel and concrete elements, the stresses distributions in the reinforcement bars and displacements of the whole column were evaluated.