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Item Restricted REAL TIME PREDICTIVE CONTROL OF UR5 ROBOTIC ARM THROUGH HUMAN UPPER LIMB MOTION TRACKING(Nazarbayev University School of Engineering and Digital Sciences) Omarali, BukeikhanThis thesis reports the authors’ results on developing a real-time predictive control system for an Universal Robot UR5 robotic arm through human motion capture with a visualization environment built in the Blender Game Engine. The UR5 is a 6 degree of freedom serial manipulator commonly used in academia and light industry. It is a very safe robot by design that comes at a cost of a rather limited API with very little support of real-time operation. The motion tracking is performed by a wireless low-cost inertial motion capture setup produced in-house. The motion tracker is an extension of author’s previous work on replacing a forearm IMU in conventional inertial motion tracking suits with a potentiometer in order remove anatomical constraints from corresponding data fusion algorithms. The external controller incorporates an iTaSC SDLS IK solver and a Python wrapped C explicit model predictive controller generated using the Multi Parametric Toolbox. The visualisation provides the user with the feedback on the robot’s progress towards the target. It is planned to extend the visualisation to virtual reality in future. Tests have shown that the robot follows the operator’s wrist position and orientation with an average of 0.05sec. time lag in the case when the operator moves under the robot’s velocity and acceleration limits. When the operator moves too fast for the robot to keep up in real-time, the robot is able to catch up with the operator with little or no overshooting. Thesis results are described in a late-breaking report and demo accepted by the 12th annual IEEE/ACM international conference Human-Robot Interaction (HRI2017).Item Open Access Existence, Uniqueness, and Numerical Analysis of Solutions of a Quasilinear ParabolicProblem(Society for Industrial and Applied Mathematics. SIAM Journal on Numerical Analysis, 1992-04) Wei, DongmingA quasilinear parabolic problem is studied. By using the method of lines, the existence and uniqueness of a solution to the initial boundary value problem with sufficiently smooth initial conditions are shown. Also given are L2 error estimates for the error between the extended fully discrete finite element solutions and the exact solution.Item Open Access Scatter Factor/Hepatocyte Growth Factor and Its Receptor, the c-met Tyrosine Kinase, Can Mediate a Signal Exchange between Mesenchyme and Epithelia during Mouse Development(The Rockefeller University Press, 1993) Sonnenberg-Riethmacher, EvaScatter factor/hepatocyte growth factor (SF/HGF) has potent motogenic, mitogenic, and morphogenetic activities on epithelial cells in vitro. The cell surface receptor for this factor was recently identified: it is the product of the c - m e t protooncogene, a receptor-type tyrosine kinase. We report here the novel and distinct expression patterns of SF/HGF and its receptor during mouse development, which was determined by a combination of in situ hybridization and RNase protection experiments. Predominantly, we detect transcripts of c - m e t in epithelial cells of various developing organs, whereas the ligand is expressed in distinct mesenchymal cells in close vicinity. In addition, transient SF/HGF and c - m e t expression is found at certain sites of muscle formation; transient expression of the c - m e t gene is also detected in developing motoneurons. SF/HGF and the c-met receptor might thus play multiple developmental roles, most notably, mediate a signal given by mesenchyme and received by epithelial. Mesenchymal signals are known to govern differentiation and morphogenesis of many epithelia, but the molecular nature of the signals has remained poorly understood. Therefore, the known biological activities of SF/HGF in vitro and the embryonal expression pattern reported here indicate that this mesenchymal factor can transmit morphogenetic signals in epithelial development and suggest a molecular mechanism for mesenchymal epithelial interactions.Item Open Access Equality and equity: An emerging government policy in northern ireland(Journal of Ethnic and Migration Studies, 1994) Knox, Colin; Hughes, JoanneA series of equality and equity measures has been introduced by the British Government to tackle the seemingly intractable problems of Northern Ireland. These measures represent a range of initiatives in the areas of social need, fair employment, education reform and community relations. The implementation of the community relations programme is considered in some detail as a case study in improving equality and equity in Northern Ireland. Qualitative data from community relations officers, charged with implementing the policy, are examined in the light of problems encountered with the programme. The influences on delivering community relations, as one component of this comprehensive thrust to attain equality and equity, are also considered using an explanatory model. The article concludes that changes in attitudes and behaviour between the two communities are occurring, albeit slowly, promoted by the measures described. © 1994, Taylor & Francis Group, LLC. All rights reserved.Item Open Access The c-ros tvrosine kinase receptor I controls regionalization and differehiation of epithelial cells in the epididymis(Cold Spring Harbor Laboratory Press, 1996) Sonnenberg-Riethmacher, Eva; Walter, Barbara; Riethmacher, Dieter; Godecke, Stephanie; Birchmeie, CarmenThe c-ros gene was originally identified in mutant form as an oncogene. The proto-oncogene encodes a tyrosine kinase receptor that is expressed in a small number of epithelial cell types, including those of the epididymis. Targeted mutations of c-ros in the mouse reveal an essential role of the gene in male fertility. Male c-ros -1- animals do not reproduce, whereas the fertility of female animals is not affected. We demonstrate that c-ros is not required in a cell autonomous manner for male germ cell development or function. The gene, therefore, does not affect sperm generation or function in a direct manner. The primary defect in the mutant animals was located in the epididymis, showing that c-ros controls appropriate development of the epithelia, particularly regionalization and terminal differentiation. The epididymal defect does not interfere with production or storage of sperm but, rather, with sperm maturation and the ability of sperm to fertilize in vivo. Interestingly, sperm isolated from c-ros - / - animals can fertilize in vitro. Our results highlight the essential role of the epididymis in male fertility and demonstrate a highly specific function of the c-ros receptor tyrosine kinase during development of distinct epithelial cellsItem Open Access Le paysage de la décolonisation de la métropole Hong Kong-Macao(L'Harmattan, 1997) Forêt, PhilippeLes facteurs apolitiques qui dirigent la mondialisation de l'économie sont en train de brutalement détruire l'architecture vernaculaire chinoise ainsi que le riche symbolisme lié à l'aménagement traditionnel du paysage. Le but de cet article est plus précisément de proposer une description des effets sur l'environnement du retour à la Chine des dernières colonies européennes en Asie orientale.Item Open Access Boundary layer receptivity and resonance caused by tuned disturbances within cascade flows(Nazarbayev University School of Engineering and Digital Sciences, 1997-05-10) Rojas-Solorzano, L.The receptivity and stability of steady non-separated and unsteady separated boundary layers in a two-dimensional airfoil cascade flow is investigated by Direct Numerical Simulation of the time-dependent Navier-stokes and continuity equations. The study includes the effects caused by the introduction of free-steam time-harmonic disturbances. The calculation of the transport, generation and dissipation of Fluctuating Kinetic Energy is introduced as a non-classical technique in the analysisItem Open Access Torsional current - meter for channels(1997 ASME Fluids Engineering Division Summer Meeting, June 22-26, 1997-06-22) Zarea, Stefan; Rojas-Solorzano, L.The main objective of this paper is to present the results of the experimental investigation of a Zarea-type torsional velocity-meter. For this, a torsional meter was designed, built and tested in the laboratory. The current meter consists of an axial rotor with blades fixed to a shaft which is in turn fixed to a rigid hub. The force of the water flow produces a torque which deforms the shaft. The current meter has been statically calibrated, thereby establishing the variational curve of the torsion angle as a function of the applied torque. A laboratory facility has been constructed in which tests were run for water speeds of up 3m/s. The torque measurements were taken by using strain gauges. The methodology and the equipment used for the experimental evaluation are shown. Additionally illustrated are the calibration curves, the analysis of obtained results, some advantages and disadvantages, and the range of application of the torsional current-meter are all discussed.Item Open Access Oscillatory momentum transport in cascade transitional boundary layer flows(DOI: 10.2514/6.1998-2560 Conference: 29th AIAA Fluid Dynamics Conference, At Albuquerque, NM, USA, Volume: 1, 1998) Rojas-Solorzano, L.The generation and early evolution of boundary layer transitional instabilities, named Tollmien-Schlichting (T-S) waves, in airfoil cascade flows are studied. The energy exchange between the mean flow and the flow instabilities is computed by performing Direct Numerical Simulation of the fluid flow governing equations and by calculating the fluctuating kinetic energy (FKE) budget within the separated boundary layer. The driving role of the FKE production in the wavelength modulation process associated to the receptivity phenomenon, i.e., the generation of T-S waves, is demonstrated. The FKE production largely hastens the wavelength modulation around the inflection point of the mean velocity profile across the boundary layer. Above the inflection point, the fluctuating pressure field favors the energy transport and provides the energy necessary to convect the instabilities out of the boundary layer. The evolution of the T-S waves depicts an asymmetric distribution of the production term in the transverse direction, i.e., in the lower half of the boundary layer the mean flow provides energy to the instabilities while the opposite occurs in the upper halfItem Open Access Effects of external disturbances on the momentum transport in cascade transitional boundary layer flows(Proceedings of FEDSM’98 1998 ASME Fluids Engineering Division Summer Meeting June 21-25, 1998, Washington, DC, 1998-06-21) Rojas-Solorzano, L.The effects on the boundary layer receptivity in airfoil cascade flow caused by superposed disturbances are studied using an energetic approach. The separated terms in the Fluctuating Kinetic Energy (FKE) budget are calculated. Monotonic time-harmonic disturbances are superposed to the inflow stream using forcing frequencies close to and far from the natural frequency of fluctuation found within the unsteady (supercritical) basic flow. For supercritical regimes, the receptivity is evaluated around the boundary layer separation point, where Tollmien-Schlichting (T-S) waves are naturally generated. For subcritical regimes, the receptivity is explored all over the suction-side of the airfoil since separation does not occur. Within subcritical flows, the superposed perturbation is seen to trigger the generation of T-S-like waves downstream the minimum pressure point only when the forcing frequency is close to n. Within supercritical flows, when the forcing frequency matches n, the FKE budget reflects the energetic interaction between the perturbation and the already existent boundary layer T-S wavesItem Open Access Peripheral nervous system defects in erbB2 mutants following genetic rescue of heart development(Cold Spring Harbor Laboratory Press, 1999) Woldeyesus, Masresha T.; Britsch, Stefan; Riethmacher, Dieter; Xu, Lan; Sonnenberg-Riethmacher, Eva; Abou-Rebyeh, Faikah; Harvey, Richard; Caroni, Pico; Birchmeier, CarmenThe ErbB2 tyrosine kinase functions as coreceptor for the neuregulin receptors ErbB3 and ErbB4 and can participate in signaling of EGF receptor (ErbB1), interleukin receptor gp130, and G-protein coupled receptors. ErbB2−/− mice die at midgestation because of heart malformation. Here, we report a genetic rescue of their heart development by myocardial expression of erbB2 cDNA that allows survival of the mutants to birth. In rescued erbB2 mutants, Schwann cells are lacking. Motoneurons form and can project to muscle, but nerves are poorly fasciculated and disorganized. Neuromuscular junctions form, as reflected in clustering of AChR and postsynaptic expression of the genes encoding the a-AChR, AChE, e-AChR, and the RI subunit of the cAMP protein kinase. However, a severe loss of motoneurons on cervical and lumbar, but not on thoracic levels occurs. Our results define the roles of Schwann cells during motoneuron and synapse development, and reveal different survival requirements for distinct motoneuron populationsItem Open Access Run Life Enlargement Methodology for Ball-and-Seat Check Valves Used in Artificial Lift Pumping Units(SPE Latin American and Caribbean Petroleum Engineering Conference, Caracas, Venezuela, 21–23 April 1999, 1999-04-21) Zarea, S.; Rojas-Solorzano, L.; Kabboul, F.Experiments are performed to evaluate the leakage vs. pressure drop, wear and fluid properties, in ball-and-seat valves used in pumping units for artificial oil production. The test facility is constructed to evaluate the operation of several valve sizes, using water, oil and air, subjected to pressure drops up to 5000 psig. Results demonstrated that the currently accepted API vacuum test might be too severe and that more realistic tests may lead to substantial savings in valve replacements. Experimental results in dimensional and dimensionless form are presented, using a new similitude criterionItem Open Access Numerical simulation of the heat penetration in two-plate arc welding(Conference: h International Congress of Numerical Methods in Engeering and Applied Science (CIMENICS 2000), At Puerto La Cruz, Venezuela, Volume: 5, 2000) Payares, C.; Rojas-Solorzano, L.; Viggiani, P.A mathematical model and numerical simulation of the three-dimensional and transient metal arc-welding process is presented. The heat source is considered as spatially distributed following a centered Gaussian bell, while the substract material (Al 6063) is assumed homogeneous and isotropic with temperature-dependent thermal properties. Radiation and convection are also calculated through an empirical temperature dependent correlation. Phase-change phenomenon is included as a discontinuity in the material specific heat. Calculations were performed by using a finite volume code (CFX4.2TM). Computed heat penetration and weld metal area are found to be in good agreement with experimental data.Item Open Access Placental Failure in Mice Lacking the Mammalian Homolog of Glial Cells Missing, GCMa(American Society for Microbiology, 2000) Riethmacher-Sonnenberg, EvaThe GCM family of transcription factors consists of Drosophila melanogaster GCM, an important regulator of gliogenesis in the fly, and its two mammalian homologs, GCMa and GCMb. To clarify the function of these mammalian homologs, we deleted GCMa in mice. Genetic ablation of murine GCMa (mGCMa) is embryonic lethal, with mice dying between 9.5 and 10 days postcoitum. At the time of death, no abnormalities were apparent in the embryo proper. Nervous system development, in particular, was not impaired, as might have been expected in analogy to Drosophila GCM. Instead, placental failure was the cause of death. In agreement with the selective expression of mGCMa in labyrinthine trophoblasts, mutant placentas did not develop a functional labyrinth layer, which is necessary for nutrient and gas exchange between maternal and fetal blood. Only a few fetal blood vessels entered the placenta, and these failed to thrive and branch normally. Labyrinthine trophoblasts did not differentiate. All other layers of the placenta, including spongiotrophoblast and giant cell layer, formed normally. Our results indicate that mGCMa plays a critical role in trophoblast differentiation and the signal transduction processes required for normal vascularization of the placentaItem Open Access Fluid flow hydrodynamic modeling in the passage of an oil artificial lift pumping unit(Proceeding of ETCE/OMAE2000 Joint Conference Energy for the New Millenium February 14-17, 2000, New Orleans, LA, 2000-02-14) Salazar S., Abraham; Rojas-Solorzano, L.The study of the two-phase flow through the standing and traveling valves used in an oil artificial-lift pumping unit is presented. The investigation aimed to determine the effects the gaseous phase may cause on the pump volumetric efficiency. Data obtained on a specially designed test facility is presented and analyzed as a first step before developing a semi-empirical model to predict the performance of the pump under two-phase flow conditions. Preliminary results, based on one-phase and two-phase runs, demonstrate important features introduced on the pump performance once the gas-phase is included in the processItem Open Access Numerical simulation of the flow through an intermittent gas lift valve(Proceeding of ETCE/OMAE2000 Joint Conference Energy for the New Millenium February 14-17, 2000, New Orleans, LA, 2000-02-14) Concho, Maria A.; Gasbarri, Sandro; Rojas-Solorzano, L.The numerical simulation of the flow through a pilot valve used in the oil intermittent gas lift process is presented.The complexity of the non-isothermal compressible flow is modeled by the solution of the Navier-Stokes, Mass Conservation and Energy equations for the compressible flow. Numerical results and analyses pertaining to the flow dynamics through a 1½-inch pilot valve at an operating condition encountered in typical field operations are presentedItem Open Access Design of a flow deflector for an accurate flow meter calibration facility(FEDSM2000 FORUM ON FLUID MEASURENMENT AND INTRUMENTATION BOSTON, MASSACHUSETTS, ON JUNE 11-15, 2000, 2000-06-11) Corrales-Barallobre, C.; Martínez-Huen, R.; Alvarez, L.; Polanco, G.; Rojas-Solorzano, L.The design and test of a flow deflector gate used for controlling the flow deviation toward the primary tank in a flow-meter calibration facility is presented. The deflector gate is pneumatically controlled and permits the flow conduction to either the suction tank or to the primary tank. The deflector is designed to approximately compensate the flow deficit towards the primary tank during the opening, with the flow excess while in the shutting process. Numerical simulations are performed to study the flow hydrodynamics during the deflector operation. Results are compared to experimental data, and used to improve the gate design. The enhanced design proved to guarantee the uniformity of the flow through the calibration section and the dramatic reduction of the error in volume measurement during calibration.Item Open Access Design of a large scale flow-meter test and calibration facility(FEDSM2000 FORUM ON FLUID MEASURENMENT AND INTRUMENTATION BOSTON, MASSACHUSETTS, ON JUNE 11-15, 2000, 2000-06-11) Corrales-Barallobre, C.; Martínez-Huen, R.; Alvarez, Luis; Polanco, G.; Rojas-Solorzano, L.The design and set up of a large-scale flowmeter calibration and test facility is presented. The facility was designed to handle flowmeters with diameters between 6” and 14”, flow rates up to 0.3 m3/s and to give results less than 1% accurate. The calibration methodology consisted firstly in calibrating the pattern flowmeters, using volume and time primary measurements, and secondly, comparing the pattern to the flowmeters needing calibration. The design and calculation of the primary calibration device is addressed, including numerical simulations of the outflow manifold and the comparison to experimental data. The calibration facility proved to be accurate and reliable in producing renewed calibration data for various tested flowmetersItem Open Access Design of the distribution manifold for a large-scale flowmeter calibration facility(FEDSM2000 FORUM ON FLUID MEASURENMENT AND INSTRUMENTATION BOSTON, MASSACHUSETTS, ON JUNE 11-15, 2000, 2000-06-11) Corrales-Barallobre, C.; Martínez-Huen, R.; Alvarez, Luis; Polanco, G.; Rojas-Solorzano, L.The design and test of the distribution manifold for a large-scale flowmeter calibration facility is presented. The design was intended to have an air-free flow operation and a free-surface flow-like towards the downstream half-body discharge. Back of the envelope calculations are presented for the estimation of the preliminary dimensions. Numerical simulations of the flow during manifold steady state operation are utilized to refine the manifold design. No air entrapment is noticed in the flow simulationItem Open Access A Penalty Method for Approximations of the Stationary Power-Law Stokes Problem(Electronic journal of differential equations, 2001) Lefton, Lew; Wei, DongmingWe study approximations of the steady state Stokes problem governed by the power-law model for viscous incompressible non-Newtonian flow using the penalty formulation. We establish convergence and find error estimates.