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Item Metadata only 13 Smart polymers for bioseparation and other biotechnological applications(Smart Polymers and their Applications, 2014-01-01) Savina, I.N.; Galaev, I. Yu.; Mikhalovsky, S.V.; I.N., SavinaAbstract: The progress in development of a number of novel products using recombinant DNA technology and cell culturing, plus the demands for high product yield whilst preserving biological activity, require novel approaches for fast and cost-effective isolation and/or purification processes. Smart polymers (SPs) with their ability to undergo considerable changes in response to external stimuli make possible the development of novel technologies for isolation and purification. In this chapter the main applications of SPs in biotechnology and, in particular, in bioseparation, are discussed. Affinity precipitation, two-phase polymer separation, using SP membranes and SP chromatographic carriers are overviewed with a presentation of recent developments and discussion of future perspectives in these areas. Application of SP as catalysts is also discussed.Item Open Access 19th International Conference on Turkish Linguistics(Nazarbayev University School of Sciences and Humanities, 2018-08-17)The Organizing Committee would like to thank… At Nazarbayev University Assel Sadykova (executive director, School of Humanities and Social Sciences), Aigerim Nurgaliyeva, Lazzat Sundetova, Ainur Yerezhepekova, Meruyert Mukanova, and Anel Kaddesova, colleagues, and student volunteers. At the International Turkic Academy President Darkhan Kydyrali, colleagues, and staff. At L.N. Gumilyov Eurasian National University Rector Erlan Syzdykov and colleagues, staff, and student volunteers. The members of the ICTL 19 Program Committee and anonymous reviewers. The participants in the cultural program from Nazarbayev University and L.N. Gumilyov Eurasian National University. Lars Johanson, Éva Á. Csató, and A. Sumru Özsoy for their encouragement to host ICTL 19 in Astana, as well as Mehmet-Ali Akinci for his kind support during the organization of the conference.Item Open Access 1D states of the beryllium atom: Quantum mechanical nonrelativistic calculations employing explicitly correlated Gaussian functions(2011) Sharkey, Keeper L.; Bubin, Sergiy; Adamowicz, LudwikVery accurate finite-nuclear-mass variational nonrelativistic calculations are performed for the lowest five 1D states (1s2 2p2, 1s2 2s1 3d1, 1s2 2s1 4d1, 1s2 2s1 5d1, and 1s2 2s1 6d1) of the beryllium atom (9Be). The wave functions of the states are expanded in terms of all-electron explicitly correlated Gaussian functions. The exponential parameters of the Gaussians are optimized using the variational method with the aid of the analytical energy gradient determined with respect to those parameters. The calculations exemplify the level of accuracy that is now possible with Gaussians in describing bound states of a four-electron system where some of the electrons are excited into higher angular statesItem Open Access 2D BI2SE3 VAN DER WAALS EPITAXY ON MICA FOR OPTOELECTRONICS APPLICATIONS(MDPI, 2020-08-22) Wang, Shifeng; Li, Yong; Ng, Annie; Hu, Qing; Zhou, Qianyu; Li, Xin; Liu, HaoBi2Se3 possesses a two-dimensional layered rhombohedral crystal structure, where the quintuple layers (QLs) are covalently bonded within the layers but weakly held together by van der Waals forces between the adjacent QLs. It is also pointed out that Bi2Se3 is a topological insulator, making it a promising candidate for a wide range of electronic and optoelectronic applications. In this study, we investigate the growth of high-quality Bi2Se3 thin films on mica by the molecular beam epitaxy technique. The films exhibited a layered structure and highly c-axis-preferred growth orientation with an XRD rocking curve full-width at half-maximum (FWHM) of 0.088◦ , clearly demonstrating excellent crystallinity for the Bi2Se3 deposited on the mica substrate. The growth mechanism was studied by using an interface model associated with the coincidence site lattice unit (CSLU) developed for van der Waals epitaxies. This high (001) texture favors electron transport in the material. Hall measurements revealed a mobility of 726 cm2 /(Vs) at room temperature and up to 1469 cm2 /(Vs) at 12 K. The results illustrate excellent electron mobility arising from the superior crystallinity of the films with significant implications for applications in conducting electrodes in optoelectronic devices on flexible substrates.Item Open Access 30 Gb/s integrated receiver array for parallel optical interconnects(IET, 2019-08) Nguyen, Nga T. H.; Ukaegbu, Ikechi; Park, Hyo-HoonA 30 Gb/s integrated receiver array for parallel optical interconnects with four channels have been designed and implemented in a 0.13 mu m CMOS technology. To achieve small area and low power consumption while maintaining large bandwidth and high gain, the integrated receiver has been implemented with a regulated cascode (RGC) transimpedance amplifier (TIA), resistive and capacitive degeneration and inductorless limiting amplifier (LA), which employs active feedback and negative capacitance. From the measurement results of the optical module using 850 nm photodiode (PD), the receiver showed a constant single-ended output swing of 320 mV up to 7.5 Gb/s/ch with clear eye diagrams and BER of <10(-12). With a voltage supply of 1.2 V, a figure of merit (FOM) of 8 mW/Gb/s was obtained with a small chip area per channel of 0.28 mm(2)/ch.Item Open Access 3D CFD Modeling Investigation of Potential Vortex Formation at the Intakes of Caruachi Powerhouse(INTERNATIONAL CONFERENCE ONHYDRAULICS OF DAMS AND RIVER STRUCTURES, TEHRAN, IRAN; 04/2004, 2004-04) Marcano, A.; Rojas-Solorzano, L.; Reyes, M.In this paper, the 3-D CFD simulation of the free-surface flow approaching the intakes of Caruachi Powerhouse is presented. The aim of the investigation is to determine whether or not vortex structures are likely to appear from the water surface through the intakes, as the result of the presence of cofferdams placed few meters upstream of the intakes. The presence of cofferdams was a note of concern with regard to the effects they might have on the turbine intakes once the hydroelectric central starts operating. In all the considered conditions, results did not show neither strong surface vortices in the proximities of the Power House intakes, nor air entrainment-entrapment towards the intakes, which reflects the safe operation of the turbines in the presence of the cofferdams. The latter added in decision taking on leaving the cofferdams submerged instead of removing them, which resulted in cost savings for the projectItem Open Access 3D HIERARCHICAL NANOCRYSTALLINE CUS CATHODE FOR LITHIUM BATTERIES(Materials, 2021-03-26) Kalimuldina, Gulnur; Nurpeissova, Arailym; Adylkhanova, Assyl; Issatayev, Nurbolat; Adair, Desmond; Bakenov, ZhumabayConductive and flexible CuS films with unique hierarchical nanocrystalline branches directly grown on three-dimensional (3D) porous Cu foam were fabricated using an easy and facile solution processing method without a binder and conductive agent for the first time. The synthesis procedure is quick and does not require complex routes. The structure and morphology of the as-deposited CuS/Cu films were characterized by X-ray diffraction and scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy and transmission electron spectroscopy, respectively. Pure crystalline hexagonal structured CuS without impurities were obtained for the most saturated S solution. Electrochemical testing of CuS/Cu foam electrodes showed a reasonable capacity of 450 mAh·g−1 at 0.1 C and excellent cyclability, which might be attributed to the unique 3D structure of the current collector and hierarchical nanocrystalline branches that provide fast diffusion and a large surface area.Item Metadata only 3D intermetallic anodes for Lithium-ion batteries(2018-12-31) Murat, E.; Adi, A.; Bakenov, Z.; Nurpeissova A.; Nurpeissova, A.Abstract Recently various three-dimensional (3D) battery architectures have emerged as a new direction for powering microelectromechanical systems and other small autonomous devices. The ultimate goal of such unique battery architecture is to obtain a high surface area substrate coated with thin layers of anode, electrolyte and cathode materials to enhance the energy density per foot print area, while maintaining a large power density. In view of this, attempts on formulating 3D structured anode utilizing widely available three dimensional mesoporous nickel foam and tin alloy matrix are reportedItem Open Access 3D MULTIDISCIPLINARY AUTOMATED DESIGN OPTIMIZATION TOOLBOX FOR WIND TURBINE BLADES(MDPI AG, 2021-03-26) Sagimbayev, Sagi; Kylyshbek, Yestay; Batay, Sagidolla; Zhao, Yong; Fok, Sai; Soo Lee, TehThis paper presents two novel automated optimization approaches. The first one proposes a framework to optimize wind turbine blades by integrating multidisciplinary 3D parametric modeling, a physics-based optimization scheme, the Inverse Blade Element Momentum (IBEM) method, and 3D Reynolds-averaged Navier-Stokes (RANS) simulation; the second method introduces a framework combining 3D parametric modeling and an integrated goal-driven optimization together with a 4D Unsteady Reynolds-averaged Navier-Stokes (URANS) solver. In the first approach, the optimization toolbox operates concurrently with the other software packages through scripts. The automated optimization process modifies the parametric model of the blade by decreasing the twist angle and increasing the local angle of attack (AoA) across the blade at locations with lower than maximum 3D lift/drag ratio until a maximum mean lift/drag ratio for the whole blade is found. This process exploits the 3D stall delay, which is often ignored in the regular 2D BEM approach. The second approach focuses on the shape optimization of individual cross-sections where the shape near the trailing edge is adjusted to achieve high power output, using a goal-driven optimization toolbox verified by 4D URANS Computational Fluid Dynamics (CFD) simulation for the whole rotor. The results obtained from the case study indicate that (1) the 4D URANS whole rotor simulation in the second approach generates more accurate results than the 3D RANS single blade simulation with periodic boundary conditions; (2) the second approach of the framework can automatically produce the blade geometry that satisfies the optimization objective, while the first approach is less desirable as the 3D stall delay is not prominent enough to be fruitfully exploited for this particular case study.Item Open Access 3D MULTIDISCIPLINARY AUTOMATED DESIGN OPTIMIZATION TOOLBOX FOR WIND TURBINE BLADES(Processes, 2021-04) Sagimbayev, Sagi; Kylyshbek, Yestay; Batay, Sagidolla; Zhao, Yong; Fok, Sai; Lee, Teh SooThis paper presents two novel automated optimization approaches. The first one proposes a framework to optimize wind turbine blades by integrating multidisciplinary 3D parametric modeling, a physics-based optimization scheme, the Inverse Blade Element Momentum (IBEM) method, and 3D Reynolds-averaged Navier–Stokes (RANS) simulation; the second method introduces a framework combining 3D parametric modeling and an integrated goal-driven optimization together with a 4D Unsteady Reynolds-averaged Navier–Stokes (URANS) solver. In the first approach, the optimization toolbox operates concurrently with the other software packages through scripts. The automated optimization process modifies the parametric model of the blade by decreasing the twist angle and increasing the local angle of attack (AoA) across the blade at locations with lower than maximum 3D lift/drag ratio until a maximum mean lift/drag ratio for the whole blade is found. This process exploits the 3D stall delay, which is often ignored in the regular 2D BEM approach. The second approach focuses on the shape optimization of individual cross-sections where the shape near the trailing edge is adjusted to achieve high power output, using a goal-driven optimization toolbox verified by 4D URANS Computational Fluid Dynamics (CFD) simulation for the whole rotor. The results obtained from the case study indicate that (1) the 4D URANS whole rotor simulation in the second approach generates more accurate results than the 3D RANS single blade simulation with periodic boundary conditions; (2) the second approach of the framework can automatically produce the blade geometry that satisfies the optimization objective, while the first approach is less desirable as the 3D stall delay is not prominent enough to be fruitfully exploited for this particular case studyItem Metadata only 3D particle size distribution of inter-ground Portland limestone/slag cement from 2D observations: Characterization and distribution evaluation(Construction and Building Materials, 2017-08-30) Sun, Hongfang; Fan, Bing; Memon, Shazim Ali; Cen, Zhuo; Gao, Xiaobin; Lin, Bin; Liu, Bing; Li, Dawang; Xing, Feng; Zhang, Xiaogang; Hongfang, SunAbstract In this research, the particle size distribution (PSD) of different components in inter-ground Portland limestone cement (PLC) and limestone-slag cement (PLC-S) was characterization by using an electron microscopy approach. Firstly, the 2D PSD of limestone, slag, and Portland cement (OPC) was determined by means of image analysis. Based on the 2D data and using a discrete stereology, the 3D size distribution was reconstructed. Finally, the PSD of inter-ground mixtures was assessed by using a compressible packing model. The results showed that the addition of limestone in cement makes the OPC component coarser and distribution broader; meanwhile, the limestone particles were found to be finer than the OPC particles. The addition of both limestone and slag (PLC-S) were found to further broaden the PSD of OPC component and limestone component with the mean size of particles increased in the following order (limestoneItem Open Access A BEM-ISOGEOMETRIC method for the ship wave-resistance problem(Ocean Engineering, 2012) Belibassakis, K.A.; Gerostathis, Th.P.; Kostas, Konstantinos; Politis, C.G.; Kaklis, P.D.; Ginnis, A.I.; Feurer, C.In the present work IsoGeometric Analysis is applied to the solution of the Boundary Integral Equation associated with the Neumann-Kelvin problem and the calculation of the wave resistance of ships. As opposed to low-order panel methods, where the body is represented by a large number of quadrilateral panels and the velocity potential is assumed to be piecewise constant (or approximated by low degree polynomials) on each panel, the isogeometric concept is based on exploiting the same NURBS basis, used for representing exactly the body geometry, for approximating the singularity distribution (and, in general, the dependent physical quantities). In order to examine the accuracy of the present method, numerical results obtained in the case of submerged and surface piercing bodies are * Corresponding author. Tel: (+30) 2107721138, Fax: (+30) 2107721397, e-mail: kbel@fluid.mech.ntua.gr 2 compared against analytical solutions, experimental data and predictions provided by the low-order panel or other similar methods appeared in the pertinent literature, illustrating the superior efficiency of the isogeometric approach. The present approach by applying Isogeometric Analysis and Boundary Element Method to the linear NK problem has the novelty of combining modern CAD systems for ship-hull design with computational hydrodynamics tools.Item Open Access A BEM-Isogeometric method with application to the wavemaking resistance problem of ships at constant speed(ASME 2011 30th International Conference on Ocean, Offshore and Arctic Engineering, 2011-06-11) Konstantinos, Belibassakis; Theodoros, Gerostathis; Konstantinos, Kostas; Constantinos, Politis; Panagiotis, Kaklis; Alexandros, Ginnis; Christian, FeurerIn the present work IsoGeometric Analysis (IGA), initially proposed by Hughes et al (2005), is applied to the solution of the boundary integral equation associated with the Neumann-Kelvin (NK) problem and the calculation of the wave resistance of ships, following the formulation by Brard (1972) and Baar & Price (1988). As opposed to low-order panel methods, where the body is represented by a large number of quadrilateral panels and the velocity potential is assumed to be piecewise constant (or approximated by low degree polynomials) on each panel, the isogeometric concept is based on exploiting the NURBS basis, which is used for representing exactly the body geometry and adopts the very same basis functions for approximating the singularity distribution (or in general the dependent physical quantities). In order to examine the accuracy of the present method, in a previous paper Belibassakis et al (2009), numerical results obtained in the case of submerged bodies are compared against analytical and benchmark solutions and low-order panel method predictions, illustrating the superior efficiency of the isogeometric approach. In the present paper we extent previous analysis to the case of wave-making resistance problem of surface piercing bodies. The present approach, although focusing on the linear NK problem which is more appropriate for thin ship hulls, it carries the IGA novelty of integrating CAD systems for ship-hull design with computational hydrodynamics solvers.Item Open Access A Chaotic Neural Network as Motor Path Generator for Mobile Robotics(IEEE International Conference on Robotics and Biomimetics, 2014) Folgheraiter, Michele; Gini, GiuseppinaThis work aims at developing a motor path generator for applications in mobile robotics based on a chaotic neural network. The computational paradigm inspired by the neural structure of microcircuits located in the human prefrontal cortex is adapted to work in real-time and used to generate the joints trajectories of a lightweight quadruped robot. The recurrent neural network was implemented in Matlab and a software framework was developed to test the performances of the system with the robot dynamic model. Preliminary results demonstrate the capability of the neural controller to learn period signals in a short period of time allowing adaptation during the robot operationItem Open Access A class of infinite convex geometries(2015) Adaricheva, Kira; Nation, J.B.Various characterizations of finite convex geometries are well known. This note provides similar characterizations for possibly infinite convex geometries whose lattice of closed sets is strongly coatomic and lower continuous. Some classes of examples of such convex geometries are givenItem Open Access A combined B-Spline-Neural-Network and ARX Model for Online Identi cation of Nonlinear Dynamic Actuation Systems(Neurocomputing, 2016) Folgheraiter, MicheleThis paper presents a block oriented nonlinear dynamic model suitable for online identi cation.The model has the well known Hammerstein architecture where as a novelty the nonlinear static part is represented by a B-spline neural network (BSNN), and the linear static one is formalized by an auto regressive exogenous model (ARX). The model is suitable as a feed-forward control module in combination with a classical feedback controller to regulate velocity and position of pneumatic and hydraulic actuation systems which present non stationary nonlinear dynamics. The adaptation of both the linear and nonlinear parts is taking place simultaneously on a patterby- patter basis by applying a combination of error-driven learning rules and the recursive least squares method. This allows to decrease the amount of computation needed to identify the model's parameters and therefore makes the technique suitable for real time applications. The model was tested with a silver box benchmark and results show that the parameters are converging to a stable value after 1500 samples, equivalent to 7.5s of running time. The comparison with a pure ARX and BSNN model indicates a substantial improvement in terms of the RMS error, while the comparison with alternative non linear dynamic models like the NNOE and NNARX, having the same number of parameters but greater computational complexity, shows comparable performances.Item Open Access A Comprehensive Review of Topical Odor-Controlling Treatment Options for Chronic Wounds: A Comprehensive Review(Journal of Wound, Ostomy and Continence Nursing, 2016-09-28) Akhmetova, Alma; Saliev, Timur; Allan, Iain U.; Illsley, Matthew J.; Nurgozhin, Talgat; Mikhalovsky, SergeyThe process of wound healing is often accompanied by bacterial infection or critical colonization, resulting in protracted inflammation, delayed reepithelization, and production of pungent odors. The malodor produced by these wounds may lower health-related quality of life and produce psychological discomfort and social isolation.Item Open Access A Cross-Cultural Perspective about the Implementation and Adaptation Process of the Schoolwide Enrichment Model(Gifted Education International, 2015) Hernández-Torrano, Daniel; Saranli, GulsahGifted education and talent development are considered today as key elements for developing human capital and increasing competitiveness within education and the economy. Within this framework, a growing number of countries have begun to invest large amounts of resources to discover and nurture their most able students. As boundaries and differences between cultures become less pronounced in a global world, educational models to guide gifted education and talent development are also becoming more widely applicable. In this context, the Schoolwide Enrichment Model (SEM) stands as a flexible model that enables schools in different regions of the world to provide individuals with opportunities to identify their potentials and to help them reach their highest levels of competence. This paper provides an overview of the SEM and the broad range of regions in which the model is currently implemented, as well as an examination of the reasons for its widespread acceptance among educators around the world. In addition, this paper includes an interview with Dr Joseph Renzulli, inventor of SEM, in which several issues related to the cultural adaptation of the SEM are discussed. Finally, the paper presents an introduction to the SEM International Network, a newly developed project created to connect SEM users around the world and to facilitate the sharing and accessing of ideas and resources for talent development.Item Open Access A design of HTM spatial pooler for face recognition using memristor-CMOS hybrid circuits(Institute of Electrical and Electronics Engineers Inc., 2016-07-29) Ibrayev, Timur; James, Alex Pappachen; Merkel, Cory; Kudithipudi, DhireeshaHierarchical Temporal Memory (HTM) is a machine learning algorithm that is inspired from the working principles of the neocortex, capable of learning, inference, and prediction for bit-encoded inputs. Spatial pooler is an integral part of HTM that is capable of learning and classifying visual data such as objects in images.Item Open Access A Double-Layer Metamaterial-Based Technique for Interference Mitigation and Shielding of Planar Microwave Structures(2016-07) Papadimopoulos, Athanasios; Karamanos, Theodosios; Tsitsas, Nikolaos; Valagiannopoulos, Constantinos; Kantartzis, Nikolaos; Tsiboukis, TheodorosAn efficient cloaking-shielding technique based on the use of a double superstrate-layer overlay is developed in this paper for planar microstrips. The metamaterial-inspired formulation reduces considerably the induced on the strip current and the reflected from the microstrip electric field, thus alleviating the electromagnetic susceptibility of microstrip transmission lines. For this purpose, the mathematical analysis and optimization procedure are founded on a semianalytic integral equation algorithm, while a set of numerical results certifies its promising merits