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The occurrence of a disaster and the appearance of a new product are items of news that can reach many people rapidly. Decision-makers would like to know how many individuals will obtain such information. In this paper, we study the case in which there are spreaders who think that the news is true and others that claim it is false. We simulate the propagation of a rumour and propose an algorithm for estimating the parameters of the resulting dynamical system. The relation between the parameters defining the simulation and the dynamical system is also studied. We conclude that the simulation describes the phenomenon well, in particular when the method proposed in this paper is used to estimate the parameters. [ABSTRACT FROM AUTHOR]

XRT separation equipment is attracting much attention as the mining industry increasingly uses pre-sorting technology. Its sorting accuracy is affected by differences in ore shape and particle size during operation. This paper, in which numerical simulations are conducted to investigate the resistance of ores under various situations, including varying blowing distances, cross-sections, and practical sizes, Additionally, this paper conducts validation tests. The test results indicate that within the 0.1-0.25 m section from the nozzle exit, there is a rapid decrease in velocity, accompanied by a significant change in ore resistance. Beyond the 0.25 m mark, the velocity reduction slows down, while the ore resistance becomes smaller. There exists a notable disparity in the resistance of ores with varying cross-sectional geometries. The size of the jet velocity surface caused by blowing distance significantly influences the resistance of ore with varying particle sizes. Furthermore, the resistance of the ore remains constant subsequent to the impact surface of the ore surpassing the surface of the jet velocity. Consequently, appropriately modifying the blowing distance, inlet pressure, and jet speed in accordance with the cross-sectional area and particle size of the majority of the ores stream can enhance the precision of the sorting process. [ABSTRACT FROM AUTHOR]

The paper presents an analysis of the impact of the number of picking aisles, slots in a rack, the size of pick lists, and the routing method on the performance of the order picking process. In the analysis, the forklift truck's maneuvers such as turns back and turns aside, omitted by some scientists, are considered. Although only random storage assignment is examined in this paper, the possible congestion effect is considered. Experiments were performed by the use of simulations. [ABSTRACT FROM AUTHOR]

The aim of the research presented in this paper was to solve one of the fundamental problems of modelling and simulation, i.e., verification of a model as a scientific tool of operations research. To attack this problem, certain crucial issues in the philosophy of science (the demarcation problem, the principle of verifiability) must be redefined. In discussing the question of verification, a procedure (the so called RAD-VER procedure) for verifying a model of a microeconomic system, in our case - a firm, is formulated. It is assumed that verification is a ceaseless process of evaluating a model's scientificity from the standpoints of deductive reasoning, coherency and empiricism. Verification has been divided into two stages: the verification of the assumptions underlying the model of a firm and the verification of the simulator. [ABSTRACT FROM AUTHOR]

Purpose: The Baker’s cysts appear within the popliteal fossa along with the progression of degenerative changes. Removal of its contents through aspiration is often a necessary complement to treatment at various stages of the development of gonarthritis. Methods: The paper presented a procedure for needle automatic needle path planning in cyst aspiration in transverse plane. The method was based on optimization and used a custom objective function, which utilized cost maps obtained from preprocessed, segmented images of the knee. The optimization was carried out with Differential Evolution. Furthermore, a preliminary sensitivity analysis was carried out. The obtained paths were compared to the reference paths proposed by an experienced surgeon. Results: The procedure was tested on 165 numerical simulations. In all of the obtained paths, the needle successfully avoided crucial objects, such as veins, arteries and nerves. Furthermore, the overall travel distance in the joint was also minimized. When compared to the reference from the surgeon, 90% of the paths were almost the same or only slightly different. Furthermore, the remaining 10% of the generated paths were viable but different. Conclusion: Based on the obtained results, the proposed solution could be a viable solution for planning the aspiration of Baker’s cyst. [ABSTRACT FROM AUTHOR]

This paper presents results of numerical simulations of a nitride semiconductor vertical-cavity surface- emitting laser (VCSEL) with a tunnel junction. The modeled laser is based on a structure created at the University of California in Santa Barbara. The analysis concerns the impact of the position of laser's active area on the emitted power. Both small detunings from the standing wave anti-node, and positioning of the active area at different anti-nodes are considered. [ABSTRACT FROM AUTHOR]

Copyright of Archives of Civil & Mechanical Engineering (Oficyna Wydawnicza Politechniki Wroclawskiej) is the property of Oficyna Wydawnicza Politechniki Wroclawskiej and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Artificial materials including various kinds of polymers like polyurethanes are more and more widely used in different branches of science and also in biomedical engineering. The paper presents the process of creating a constitutive equation for a polyurethane nanocomposite which is considered to be hyper-elastic. The constitutive modelling was conducted within the range of application of the material as one of the components of lumbar intervertebral disc prosthesis. In the paper, the biomechanics of the lumbar spine and the most frequently applied intervertebral disc prostheses are described. Also a polyurethane nanocomposite as a new material to be applied in prostheses is presented. The way of formulating a constitutive equation by means of mathematical formulae is described. Four various hyper-elastic potential functions are considered, i.e., Ogden, Neo-Hookean, Yeoh and Mooney-Rivlin. On the basis of monotonic compression tests the best hyper-elastic model for the material considered was chosen and hyper-elastic constants were calibrated. Finally, the constitutive model was validated on the basis of FE analysis. The paper ends with a conclusion and presentation of further plans of research directed towards the development of a constitutive equation and its application in computer simulations by means of the finite element method. [ABSTRACT FROM AUTHOR]

In this paper, the method of generating biped robot motion using recorded human gait is presented. The recorded data were modified taking into account the velocity available for robot drives. Data includes only selected joint angles, therefore the missing values were obtained considering the dynamic postural stability of the robot, which means obtaining an adequate motion trajectory of the so-called Zero Moment Point (ZMT). Also, the method of determining the ground reaction forces' distribution during the biped robot's dynamic stable walk is described. The method was developed by the authors. Following the description of equations characterizing the dynamics of robot's motion, the values of the components of ground reaction forces were symbolically determined as well as the coordinates of the points of robot's feet contact with the ground. The theoretical considerations have been supported by computer simulation and animation of the robot's motion. This was done using Matlab/Simulink package and Simulink 3D Animation Toolbox, and it has proved the proposed method. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to present the computational model of skeletal muscle, which was treated as the structure of different mechanical properties. The method of identification of those properties is described in detail. In addition, the method of quantitative and qualitative verification of this model is proposed. Applying this computational model, the forces of real muscles can be evaluated without using any optimization technique. Such an approach will be described in the part II of the paper. [ABSTRACT FROM AUTHOR]

Minimum resolvable temperature difference (MRTD) is considered as the most important parameter of thermal imagers. A new method of MRTD measurement without drawbacks of other methods is presented in this paper. Proposed MRTD measurement method coded as virtual MRTD is based on a three steps measurement concept using semi-automatic objective measurements and computer simulation. First, objective parameters of the tested thermal imager are measured. Second, software simulates this tested thermal imager and generates the image of 4-bar target of specified spatial frequency (size) and contrast (temperature difference). Third, a human observer analyses the images of the 4-bar target generated by the software on the screen of PC set and measures MRTD of the simulated thermal imager at specified set of spatial frequencies. The proposed method offers higher measurement speed, lower cost and typically better accuracy in comparison with the typical MRTD measurement method. [ABSTRACT FROM AUTHOR]

In this paper, we reveal the transmission properties of the M-type combined solitary wave in birefringent fiber with third-order dispersion, self-frequency shift, self-steepening, fifth-order nonlinearity and the gain (loss) effects. The numerical simulations show that the M-type solitary wave can be stably transmitted through 300 dispersion lengths via balancing the variety of effects. And it can even be stably transmitted under the condition of limited interference under a small perturbation of noise, amplitude and phase position. The results can provide certain references for the research of optical soliton communication and optical devices. [ABSTRACT FROM AUTHOR]

Purpose: This paper is mainly about biomechanical behavior of needle insertion into cornea, and proposes a failure criterion to simulate the insertion process which has attracted considerable attention due to its importance for the minimally invasive treatment. Methods: In the process of needle insertion into cornea, tiny and complex insertion force is generated due to contact between needle and soft tissue. Based on the distortion energy theory, there is proposed a failure criterion of corneal material that can solve contact problem between rigid body and biological tissue in insertion simulation, where Cauchy stress of corneal material is the key to numerical calculation. A finite element model of in vivo cornea is built, and the cornea constrained by sclera is simplified to two layers containing epithelium and stroma. Considering the hyper-viscoelastic property of corneal material, insertion simulation is carried out. Results: By insertion experiment, the insertion force increases with insertion depth accompanying obvious fluctuations. Different insertion forces are generated at different speeds. The punctured locations are obvious in the force-displacement curves. The results of insertion simulation are generally consistent with experimental data. Maps of von Mises stress reflect the tissue injury of the cornea during insertion process, and punctured status corresponds to the point in the curves. Conclusions: The ability of this study to reproduce the behavior of needle insertion into cornea opens a promising perspective for the control of robotic surgery operation as well as the real-time simulation of corneal suture surgery. [ABSTRACT FROM AUTHOR]

Purpose: In this paper, the effect of initial density distribution upon the predicted density via numerical simulations of bone remodeling was evaluated. The main purpose was to correlate the numerical results with clinical data according to which the initial bone quantity is an essential factor for long term survival of dental implants., Methods: Two-strain energy density-based bone remodeling theories were employed, one which accounts for overload resorption and the second one, which does not. The remodeling parameters were derived from the mechanostat theory. Bone remodeling around an osseointegrated dental implant was simulated based on finite element method using a generic mandible plane model. A variable time step was introduced to increase the speed of the remodeling simulations by keeping the truncation errors small. The simulations were performed for several initial density distributions correlated with values from clinical classifications of bone quality. For each density value, the occlusal load was defined in two ways so that to consider normal and overload mastication forces, respectively., Results: The results showed that the initial density distribution influences the predictions of bone remodeling simulations. For the analyzed model, the remodeling algorithm predicted overload resorption only in the case of low initial density, which can be associated with low bone quality, which, from clinical perspective, may probably lead to implant loss., Conclusions: The paper demonstrated that when simulating bone remodeling around dental implants using finite element method, it is important to account for initial density distribution in correlation with the bone quantity.

Image contrast and visibility associated with underwater optical imaging systems are usually degraded by the absorbing and scattering effects of turbid waters. To improve the image contrast, laser-range -gate has been widely applied to underwater optical imaging systems. The work of KATSEV et al. (Appl. Opt. 38(33), 1999, pp. 6849-6858) shows that the contrast of a shadow image is greater than that of the object image. The present paper outlines a Monte Carlo based simulation method of image formation for underwater optical imaging. It is found that the contrast of a shadow image varies with gate starting depths. The angular distribution of multiply scattered photons is obtained via semi-analytical models (SHENGFU LI et al., Opt. Commun. 381, 2016, pp. 43-47). The simulated results show that increasing the gate starting depth can reduce the highly backscattered photons, thus can improve the image contrast. [ABSTRACT FROM AUTHOR]

In this paper, we have obtained theoretically a convenient way to improve the tandem solar cell efficiency by using one-dimensional binary photonic crystals in the anti-reflection coating and intermediate reflective layer. Also, we design and simulate our structure by using two different methods; MATLAB program based on a transfer matrix method and COMSOL Multiphysics software based on a finite element method. We have obtained the localization of the photons energy on the appropriate cell and then reduced the energy losses by controlling the photonic band gap. The present design is more convenient for cold countries. [ABSTRACT FROM AUTHOR]

The article focuses on papers presented at the "Surface Physics and Thin-Films Structure Seminar" held in Poland on May 17-21, 2005. The papers are devoted to analysis of the physical and thermal phenomena occurring in advanced device structures, with some research being carried out with the aid of computer modeling. Majority of topics focuses the technology of III-V semiconductors and other compound materials, including the results related to the techniques, growth and characterization of low-dimensional structures.

This paper studies the perturbation theory of optical solitons with log law nonlinearity. The adiabatic dynamics of the Gausson parameters are determined in the presence of the perturbation terms. The fixed point is also found and finally the numerical simulation is carried out. [ABSTRACT FROM AUTHOR]

Copyright of Archives of Civil & Mechanical Engineering (Oficyna Wydawnicza Politechniki Wroclawskiej) is the property of Oficyna Wydawnicza Politechniki Wroclawskiej and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper presents a numerical design of a large effective mode area microstructure optical fiber. Using the finite difference time domain numerical simulation method it is shown that the proposed fiber can assume very high effective area of the order 122 to 252 µm², negative dispersion-flat properties around the 1550 nm wavelength, and very low confinement losses of the order 10-5 dB/km. A hexagonal eight ring silica-air microstructure is used with two air-hole dimensions and a common pitch. A microstructure optical fiber with large effective mode area, low confinement loss, and dispersion-flat property may be promising for next generation optical data transmission applications. [ABSTRACT FROM AUTHOR]

The paper describes the influence of barium titanate BaTiO3 used as a filler in impregnating epoxy resin on electrical parameters of obtained material. The results of computer simulation of electric field intensity distribution in area of 220 kV ac composite insulator show that in order to reduce the maximum value of this field it is necessary to use the rod with the highest possible permittivity. It was assumed that the increase of rod permittivity is possible by doping the epoxy resin, being one of glass-epoxy rod components, with a filler having high permittivity. Barium titanate BaTiO3 in micro- and nanograins was used as a filler. Presumably, such a change in material structure, may negatively influence other electrical parameters of the material, important in composite insulators construction. In order to check the filler dispersion in epoxy matrix, microscopic observations of fractions of the obtained materials were performed. In a wide range of frequencies, the permittivity and volume resistivity of the materials were determined. The inception voltage of partial discharges on surface of materials was determined by the electric, acoustic and antenna methods. [ABSTRACT FROM AUTHOR]

Copyright of Archives of Civil & Mechanical Engineering (Oficyna Wydawnicza Politechniki Wroclawskiej) is the property of Oficyna Wydawnicza Politechniki Wroclawskiej and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Operations Research & Decisions is the property of Oficyna Wydawnicza Politechniki Wroclawskiej and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Purpose: This paper is mainly about biomechanical behavior of needle insertion into cornea, and proposes a failure criterion to simulate the insertion process which has attracted considerable attention due to its importance for the minimally invasive treatment., Methods: In the process of needle insertion into cornea, tiny and complex insertion force is generated due to contact between needle and soft tissue. Based on the distortion energy theory, there is proposed a failure criterion of corneal material that can solve contact problem between rigid body and biological tissue in insertion simulation, where Cauchy stress of corneal material is the key to numerical calculation. A finite element model of in vivo cornea is built, and the cornea constrained by sclera is simplified to two layers containing epithelium and stroma. Considering the hyper-viscoelastic property of corneal material, insertion simulation is carried out., Results: By insertion experiment, the insertion force increases with insertion depth accompanying obvious fluctuations. Different insertion forces are generated at different speeds. The punctured locations are obvious in the force-displacement curves. The results of insertion simulation are generally consistent with experimental data. Maps of von Mises stress reflect the tissue injury of the cornea during insertion process, and punctured status corresponds to the point in the curves., Conclusions: The ability of this study to reproduce the behavior of needle insertion into cornea opens a promising perspective for the control of robotic surgery operation as well as the real-time simulation of corneal suture surgery.

Purpose: This paper deals with the mathematical modeling of the thermal processes occurring in the tooth, during a very brief contact (a few seconds) with a very cold liquid on a part of the tooth crown. In this way one can simulate a heat transfer in tooth proceeding during a dental diagnostic test - pulp vitality testing. The impact of rapid ambient thermal changes acting on the tooth can cause toothache., Methods: The mathematical model: a system of partial differential equations with initial-boundary conditions (the axiallysymmetrical problem) and their numerical solutions using the control volume method is discussed., Results: Simulation results of the kinetics of the temperature changes inside the tooth are presented. The example of the control volume mesh (using the Voronoi polygons) well describing the shape of a molar tooth is given., Conclusions: The simulation results (the temperature distribution in the tooth at any moment of the simulation time and the kinetics of temperature variation at the points of the tooth domain considered) can help dentists in the selection of an appropriate method of treatment.

In this paper we describe the numerical model of a semiconductor disk laser, developed and implemented in the Photonics Group, Institute of Physics, Lodz University of Technology, Poland. It consists of four strongly interrelated components for: carrier transport, heat flow, material gain and optical phenomena calculations. Combination of these components gives the steady-state self-consistent model which enables a simulation of various aspects of a semiconductor disk laser operation. A numerical analysis of carrier and power losses within the active region of 1.3-μm GaInNAs/GaAs semiconductor disk laser has been carried out using this model. [ABSTRACT FROM AUTHOR]

Some basic problems related to measurements of electrical impedance of biological objects (bioimpedance) have been presented in this paper. Particularly problems arising from impedance occurring at the sensor-tissue interface (interfacial impedances) in contact measuring methods have been discussed. The influence of finite values of impedances of the current source and voltage measuring device has also been taken into consideration. A model of the impedance sensor for the four-electrode measurement method containing the interfacial, source and measuring device impedances has been given and its frequency characteristics obtained by the computer simulation have been presented. The influence of these impedances on the shape of frequency characteristic of the sensor model has been discussed. Measurements of bioimpedance of healthy and anomalous soft tissues have been described. Some experimental results, particularly the frequency characteristics of bioimpedance, have been shown. The presented results of measurement show that bioimpedance can be a valuable source of information about the tissues, so measurement of bioimpedance can be a useful supplement to other medical diagnostic methods. [ABSTRACT FROM AUTHOR]

A continuous and dynamic development of medical sciences which is currently taking place all over the world is associated with a considerable increase in the number of scientific reports and papers of importance in enhancing the effectiveness of treatment and quality of medical care. However, it is difficult, or, indeed, impossible, for physicians to regularly follow all recent innovations in medical knowledge and to apply the latest research findings to their daily clinical practice. More and more studies conducted both in Poland and worldwide as well as experience from clinical practice in various countries provide convincing evidence that various systems supporting medical decision-making by physicians or other medical professionals visibly improve the quality of medical care. The use of such systems is already possible and recently has been developing especially dynamically, as the level of knowledge and information and communication technology now permits their effective implementation. Currently, electronic knowledge bases, together with inference procedures, form intelligent medical information systems, which offer many possibilities for the support of medical decision-making, mainly in regard to interactive diagnostic work-up, but also the selection of the most suitable treatment plan (clinical pathway). Regardless of their scale and area of application, these systems are referred to as Computer-Based Medical Decision Support Systems (CBMDSS).

In this study, the influence of air inlet layout on the flow field distribution and particle movement trajectory for the vertical turbo air classifier are analyzed comparatively using the numerical simulation method. The air inlet layout adjustment can increase the axial velocity and turbulent dissipation rate at the feeding inlet and do not generate the axial negative velocity, which improves powder material pneumatic transportation and dispersion capacity; the air inlet layout adjustment can match the airflow rotation direction with the rotation direction of the rotor cage, which can eliminate the vortices in the rotor cage channel effectively. Moreover, the particle movement time is shortened and fast classification is completed, which can decrease the particle agglomeration probability and weaken the 'fish-hook' effect. The optimization scheme of the air inlet layout is Type-BC. In accordance with the numerical simulation results, the calcium carbonate classification experimental results indicate that the classification performance of the classifier is improved using Type-BC. [ABSTRACT FROM AUTHOR]

The paper presents the results of a study on mechanical properties of porcine temporomandibular joint discs. Taking into account anatomical properties, three typical spots were selected for the investigation: the posterior, anterior and central parts of the disc. The main focus was on the influence of samples' preparation on the changes in mechanical properties. Complete undamaged discs, cylindrically cut disc samples of 5 mm in diameter as well as discs of locally broken continuity in the upper layer around the measuring zone were prepared. Periodic compression was applied during testing, by varying the force in a sawtooth control signal. The rate of increasing the force applied equalled 1 N/s with a maximum value of 3 N. Based on the stress and strain characteristics obtained, the object's rigidity, Young's modulus of the samples, and effective Young's modulus of joint discs were calculated. Results showed that the stress and strain characteristics of the discs' substance depend on sample preparation, measurement location and load history within a given number of cycles. Only the fifth load cycle may be considered as stabilized. The most rigid proved to be the posterior part of the disc, as the rigidity of the samples, of an incised disc and of a complete disc in the fifth loading cycle amounted to 117.9 N/mm, 88.8 N/mm and 87.1 N/mm, respectively. A central part of the disc exhibited the lowest rigidity, whose values for the samples, for an incised disc and for a complete disc reached 87.9 N/mm, 70.6 N/mm, and 38.7 N/mm, respectively. Excision of the samples resulted in their dehydration, which led to increased rigidity, as reflected by Young's modulus values. In the posterior part of the disc, the modulus value was 12.56 MPa, while in the anterior part and in the center, these values reached 7.25 MPa and 6.99 MPa, respectively. Excised discs also exhibited dehydration effects during examination. While loading complete discs, the lowest effective values of Young's modulus were obtained, despite the influence of the tissues adjacent to the loaded zone, counteracting deformation. The values were 4.44 MPa, 1.97 MPa and 2.99 MPa for the posterior, central and anterior parts, respectively. Present data allow the conclusion that the error introduced due to breaking the tissue continuity is greater than the error resulting from ignoring substance continuity when applying local loads to an undamaged disc. Therefore, it seems more sensible to adopt the effective Young's modulus values in numerical analyses rather than to apply the results obtained for the samples cut out of discs.

Navigation systems track objects with precision expressed as root mean square equalling even up to 0.15 mm. Application of navigation system combined with imaging technique makes surgical operations less invasive, which results in the reduced risk of infection, smaller scar and a shorter time of rehabilitation. Imaging techniques allow surgeon to create individual virtual models for virtual surgery planning. Navigation system tracks the positions of surgical tools in relation to the patient's coordinate systems. Medical imaging enables low-invasive surgery, whereas the position of surgical instruments is monitored on screen. The paper presents a newly developed computer-aided surgical system consisting of ultrasonographic probe and tracking system to measure bone geometry, design surgical scenario virtually and follow it intraoperatively. The system assists surgeon to correct bone deformities. The paper presents the results of several accuracy tests, which demonstrate good repeatability and accuracy.

So far applanation tonometry has not worked out any theoretical basis for correcting the result of intraocular pressure measurement carried out on a cornea with noncalibration dimensions by means of the Goldmann tonometer. All the tables of instrument reading corrections for cornea thickness or cornea curvature radius are based exclusively on measurements. This paper represents an attempt at creating a mechanical description of corneal apex deformation in Goldmann applanation tonometry. The functional dependence between intraocular pressure and the pressure exerted on the corneal apex by the tonometer was determined from a biomechanical model. Numerical GAT simulations, in which this function was also interrelated with the cornea's curvature radius and thickness were run and a constitutive equation for applanation tonometry, i.e. a full analytical description of intraocular pressure as a function of the above variables, was derived on this basis. The correction factors were defined and an algorithm for correcting the measured pressure was formulated. The presented formalism puts the results of experimental tonometry in new light. Analytical correction factors need not to come exclusively from measurements. A geometric interdependence between them and their dependence on pressure have been revealed. The theoretical description of applanation tonometry contained in the constitutive equation consists of a pressure function developed for a cornea with calibration dimensions and a coefficient correcting this calibration function, dependent exclusively on the cornea's actual thickness and curvature radius. The calibration function is a generalization of the Imbert-Fick law. [ABSTRACT FROM AUTHOR]

In laparoscopic operations of abdominal hernias some recurrences still take place, even when applying a surgical mesh. This is usually caused by a failure of the connection between the tissue and the implant. The study deals with the influence of an implant's orientation on forces in joints, which connect the mesh to human tissues. In the paper, the implant is modelled as a membrane structure within framework of the Finite Element Method. Two models are analysed: in the first one interaction between the mesh and a fascia is taken into account, in the second this interaction is not considered. Computations are conducted for two different material types of the implants: one with isotropic properties and second one with orthotropic properties. The models are validated by comparing dynamic numerical analysis with experimental outcomes, where load was simulating intraabdominal pressure during postoperative cough. Due to displacements of joints during activities like bending sideways or torsion of an abdomen, influence of kinematic extortions on forces in the joints is analysed. The outcome shows that position of the orthotropic implants is crucial and may strongly change the level of forces in the joints. [ABSTRACT FROM AUTHOR]

The dependence of transmission characteristics on acoustic frequency for an SMF-based acousto-optic tunable filter has been investigated in this paper. Experimental results indicate that multi-resonance peaks may turn up in the transmission spectrum when applied acoustic frequency is sufficiently high, and resonance wavelengths increase in proportion to the applied acoustic frequency for short resonance wavelength region, while they have opposite acoustic frequency responses for longer resonance wavelength region. Our numerical simulation proves that this phenomenon could be attributed to the non-monotonic phase matching curves of acoustic gratings, which would be helpful for the understanding of mode coupling mechanism in fiber acoustic gratings and design of fiber-based acousto-optic devices. [ABSTRACT FROM AUTHOR]

Copyright of Archives of Civil & Mechanical Engineering (Oficyna Wydawnicza Politechniki Wroclawskiej) is the property of Oficyna Wydawnicza Politechniki Wroclawskiej and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Archives of Civil & Mechanical Engineering (Oficyna Wydawnicza Politechniki Wroclawskiej) is the property of Oficyna Wydawnicza Politechniki Wroclawskiej and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Archives of Civil & Mechanical Engineering (Oficyna Wydawnicza Politechniki Wroclawskiej) is the property of Oficyna Wydawnicza Politechniki Wroclawskiej and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Archives of Civil & Mechanical Engineering (Oficyna Wydawnicza Politechniki Wroclawskiej) is the property of Oficyna Wydawnicza Politechniki Wroclawskiej and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Archives of Civil & Mechanical Engineering (Oficyna Wydawnicza Politechniki Wroclawskiej) is the property of Oficyna Wydawnicza Politechniki Wroclawskiej and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Archives of Civil & Mechanical Engineering (Oficyna Wydawnicza Politechniki Wroclawskiej) is the property of Oficyna Wydawnicza Politechniki Wroclawskiej and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Archives of Civil & Mechanical Engineering (Oficyna Wydawnicza Politechniki Wroclawskiej) is the property of Oficyna Wydawnicza Politechniki Wroclawskiej and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Operations Research & Decisions is the property of Oficyna Wydawnicza Politechniki Wroclawskiej and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Archives of Civil & Mechanical Engineering (Oficyna Wydawnicza Politechniki Wroclawskiej) is the property of Oficyna Wydawnicza Politechniki Wroclawskiej and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Archives of Civil & Mechanical Engineering (Oficyna Wydawnicza Politechniki Wroclawskiej) is the property of Oficyna Wydawnicza Politechniki Wroclawskiej and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Operations Research & Decisions is the property of Oficyna Wydawnicza Politechniki Wroclawskiej and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Environment Protection Engineering is the property of Oficyna Wydawnicza Politechniki Wroclawskiej and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Archives of Civil & Mechanical Engineering (Oficyna Wydawnicza Politechniki Wroclawskiej) is the property of Oficyna Wydawnicza Politechniki Wroclawskiej and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Investigations of anomalous behaviour of the reaction diffusion front for A + B → 2C (inert) and A + B → CC processes are presented. Computer simulation studies were performed using the model of dynamic lattice liquid (DLL) for both two- and three-dimensional cases. Special attention was paid to situations when the mobility of products C and CC significantly differs from the mobilities of reactants. Under such conditions, new kinds of dynamical behaviour were detected. The results obtained indicate that it is necessary to re-formulate the classical description of reaction diffusion front problem. The generalized formalism suggested in the paper should allow a proper description of dynamics of the reaction front over the whole time range including the case when the mobilities of reactants and products are different. [ABSTRACT FROM AUTHOR]

Copyright of Operations Research & Decisions is the property of Oficyna Wydawnicza Politechniki Wroclawskiej and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Enhanced gravity concentrator have excellent separation accuracy for the fine mineral particles. However, its internal flow characteristics are still in unclear. Therefore, numerical simulation was conducted to study the flow characteristics of concentrator. Effect of centrifugal force and fluidization water pressure on the velocity component of fluid was studied. The simulation accuracy was verified by the theoretical calculation. The turbulence intensity in the radial direction was analyzed to reveal the gradient characteristics. Results show that the three-dimensional velocity has different order of magnitude. The increase of centrifugal force significantly improves the three-dimensional velocity of fluid. However, the fluidization water pressure has little influence on the tangential velocity and axial velocity, but it can effectively improve the radial velocity. High turbulent flow energy and high turbulence dissipation rate are presented in the near wall region, which allows the light particles reentering the separation region. Meanwhile, the fluid presents stable flow pattern in the fall wall region that is conducive to the stratification process. In addition, the increase of centrifugal force increases the turbulence in the near wall region; however, fluidization pressure has no effect. [ABSTRACT FROM AUTHOR]