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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 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 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 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 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 fair opportunistic relaying algorithm using an adaptive selection region in cooperative networks(VDE, 2016-05-18) Mahdi Azari, Mohammad; Pollin, Sofie; Rosas, Fernando; Maham, Behrouz; Zhou, XiangyunThis work proposes a new relay selection algorithm in an opportunistic cooperative network, which aims to establish fairness among the users. Our approach provides the same overall outage probability for users at different locations.Item Open Access A free-standing sulfur/nitrogen-doped carbon nanotube electrode for high- performance lithium/sulfur batteries(Nanoscale Research Letters a Springer Open Journal (2015), 2015-12) Zhao, Yan; Yin, Fuxing; Zhang, Yongguang; Zhang, Chengwei; Mentbayeva, Almagul; Umirov, Nurzhan; Xie, Hongxian; Bakenov, ZhumabayA free-standing sulfur/nitrogen-doped carbon nanotube (S/N-CNT) composite prepared via a simple solution method was first studied as a cathode material for lithium/sulfur batteries. By taking advantage of the self-weaving behavior of N-CNT, binders and current collectors are rendered unnecessary in the cathode, thereby simplifying its manufacturing and increasing the sulfur weight ratio in the electrode. Transmission electronic microscopy showed the formation of a highly developed core-shell tubular structure consisting of S/N-CNT composite with uniform sulfur coating on the surface of N-CNT. As a core in the composite, the N-CNT with N functionalization provides a highly conductive and mechanically flexible framework, enhancing the electronic conductivity and consequently the rate capability of the material.Item Open Access A free-standing sulfur/nitrogen-doped carbon nanotube electrode for high- performance lithium/sulfur batteries(Nanoscale Research Letters., http://www.nanoscalereslett.com/content/10/1/450, 2015-11-19) Zhao, Yan; Yin, Fuxing; Zhang, Yongguang; Zhang, Chengwei; Mentbayeva, Almagul; Umirov, Nurzhan; Xie, Hongxian; Bakenov, ZhumabayA free-standing sulfur/nitrogen-doped carbon nanotube (S/N-CNT) composite prepared via a simple solution method was first studied as a cathode material for lithium/sulfur batteries. By taking advantage of the self-weaving behavior of N-CNT, binders and current collectors are rendered unnecessary in the cathode, thereby simplifying its manufacturing and increasing the sulfur weight ratio in the electrode. Transmission electronic microscopy showed the formation of a highly developed core-shell tubular structure consisting of S/N-CNT composite with uniform sulfur coating on the surface of N-CNT. As a core in the composite, the N-CNT with N functionalization provides a highly conductive and mechanically flexible framework, enhancing the electronic conductivity and consequently the rate capability of the material.Item Open Access A Joint Tensor Completion and Prediction Scheme for Multi-Dimensional Spectrum Map Construction(IEEE Access, 2016-11-14) Tang, Mengyun; Ding, Guoru; Wu, Qihui; Xue, Zhen; Tsiftsis, Theodoros A.Spectrum data, which are usually characterized by many dimensions, such as location, frequency, time, and signal strength, present formidable challenges in terms of acquisition, processing, and visualization. In practice, a portion of spectrum data entries may be unavailable due to the interference during the acquisition process or compression during the sensing process. Nevertheless, the completion work in multi-dimensional spectrum data has drawn few attention to the researchers working in the eld. In this paper, we rst put forward the concept of spectrum tensor to depict the multi-dimensional spectrum data. Then, we develop a joint tensor completion and prediction scheme, which combines an improved tensor completion algorithm with prediction models to retrieve the incomplete measurements. Moreover, we build an experimental platform using Universal Software Radio Peripheral to collect real-world spectrum tensor data. Experimental results demonstrate that the effectiveness of the proposed joint tensor processing scheme is superior than relying on the completion or prediction scheme only.Item Open Access A Matching-Game-Based Energy Trading for Small Cell Networks with Energy Harvesting(2015 IEEE 26th Annual International Symposium on Personal, Indoor, and Mobile Radio Communications (PIMRC), 2015) Reyhanian, Navid; Maham, Behrouz; Shah-Mansouri, Vahid; Yuen, ChauDeploying small cells in cellular networks, as a technique for capacity and coverage enhancement, is an indispensable characteristic of future cellular networks. In this paper, a novel online decentralized algorithm for enabling energy trading in multitier cellular networks with selfish energy harvesting capable base stations (BSs) is proposed. A BS uses the non-renewable energy when it cannot harvest sufficient energy to serve its connected users. To minimize the non-renewable energy consumption, we establish a framework for trading energy such that BSs with energy deficit are stimulated to compensate their energy shortage with the extra harvested energy of other BSs. BSs with energy deficit are assigned to BSs with extra harvested energy by using matching theory. The extra harvested energy is distributed by the smart grid. Along with energy trades, BSs gain more profit and their utility functions enhance. Simulation results show that the waste of energy due to limited batteries and the non-renewable energy consumption decreases considerably when the proposed algorithm is appliedItem Open Access A novel lithium/sulfur battery based on sulfur/graphene nanosheet composite cathode and gel polymer electrolyte(Nanoscale Research Letters., http://www.nanoscalereslett.com/content/9/1/137, 2014) Zhang, Yongguang; Zhao, Yan; Bakenov, ZhumabayA novel sulfur/graphene nanosheet (S/GNS) composite was prepared via a simple ball milling of sulfur with commercial multi-layer graphene nanosheet, followed by a heat treatment. High-resolution transmission and scanning electronic microscopy observations showed the formation of irregularly interlaced nanosheet-like structure consisting of graphene with uniform sulfur coating on its surface. The electrochemical properties of the resulting composite cathode were investigated in a lithium cell with a gel polymer electrolyte (GPE) prepared by trapping 1 mol dm−3 solution of lithium bistrifluoromethanesulfonamide in tetraethylene glycol dimethyl ether in a polymer matrix composed of poly(vinylidene fluoride-co-hexafluoropropylene)/poly(methylmethacrylate)/silicon dioxide (PVDF-HFP/PMMA/SiO2). The GPE battery delivered reversible discharge capacities of 809 and 413 mAh g−1 at the 1st and 50th cycles at 0.2C, respectively, along with a high coulombic efficiency over 50 cycles. This performance enhancement of the cell was attributed to the suppression of the polysulfide shuttle effect by a collective effect of S/GNS composite cathode and GPE, providing a higher sulfur utilization.Item Open Access A passive wireless tracking system for indoor assistive monitoring(IEEE Computer Society, 2016) Hee Kho, Yau; Soon Chong, Nguan; Caglar Kizilirmak, RefikThis paper presents a design concept and implementation of an indoor passive tracking system that utilises an array of Wi-Fi transceivers, and without any electronic device or tag attached to the object being tracked. Such tracking is made possible by exploiting the fundamental characteristic of signal attenuation due to object blocking, i.e. shadowing, that is prevalent in a typical wireless communication system.Item Open Access A simple approach to synthesize novel sulfur/graphene oxide/multiwalled carbon nanotube composite cathode for high performance lithium/sulfur batteries(Ionics, 2016) Yuan, Guanghui; Zhao, Yan; Jin, Huafeng; Bakenov, ZhumabayA sulfur/graphene oxide/multiwalled carbon nanotube (S/GO/MWNT) composite was synthesized via a simple ultrasonic mixing method followed by heat treatment. By taking advantage of this solution-based self-assembly synthesis route, poisonous and noxious reagents and complicated fabrication processes are rendered unnecessary, thereby simplifying its manufacturing and decreasing the cost of the final product.Item Open Access A simple method for the production of large volume 3D macroporous hydrogels for advanced biotechnological, medical and environmental applications(Scientific Reports, 2016-02-17) Savina, Irina N.; Ingavle, Ganesh C.; Cundy, Andrew B.; Mikhalovsky, Sergey V.The development of bulk, three-dimensional (3D), macroporous polymers with high permeability, large surface area and large volume is highly desirable for a range of applications in the biomedical, biotechnological and environmental areas. The experimental techniques currently used are limited to the production of small size and volume cryogel material. In this work we propose a novel, versatile, simple and reproducible method for the synthesis of large volume porous polymer hydrogels by cryogelation.