School of Engineering and Digital Sciences

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Nazarbayev University School of Engineering and Digital Sciences aims to be the leading school of engineering in Kazakhstan as well as in the Central Asian region. The School’s objective is to ensure that its graduates are well-prepared to meet the growing demand for flexible professional practitioners in the fields of chemical, mechanical, civil and electrical engineering, to work as the good inventors, scientists, managers and advisers. Please have a look at the School of Engineering and Digital Sciences website.

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    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., Savina
    Abstract: 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.
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    30 Gb/s integrated receiver array for parallel optical interconnects
    (IET, 2019-08) Nguyen, Nga T. H.; Ukaegbu, Ikechi; Park, Hyo-Hoon
    A 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.
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    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 project
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    3D HIERARCHICAL NANOCRYSTALLINE CUS CATHODE FOR LITHIUM BATTERIES
    (Materials, 2021-03-26) Kalimuldina, Gulnur; Nurpeissova, Arailym; Adylkhanova, Assyl; Issatayev, Nurbolat; Adair, Desmond; Bakenov, Zhumabay
    Conductive 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.
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    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 reported
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    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, Teh
    This 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.
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    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 Soo
    This 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
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    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, Sun
    Abstract 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 (limestone
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    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.
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    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, Feurer
    In 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.
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    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, Sergey
    The 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.
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    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, Dhireesha
    Hierarchical 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.
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    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, Xiangyun
    This 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.
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    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, Zhumabay
    A 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.
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    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, Zhumabay
    A 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.
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    A geospatial model to determine patterns in river ice cover breakup and jamming behaviour
    (2014-08) Sagin, Jay
    In the past, both empirical and process-based attempts have been made to predict river ice behaviour, in particular ice cover breakup and ice jamming occurrences. These methods perform with varying and limited success and tend to be site specific. A method is required which can simply estimate the predisposition of river reaches to ice breakup and jamming events. This paper introduces a geospatial modelling approach which can fulfil that task and improve the predictive power of ice cover breakup and ice jamming behaviour. The geospatial model can determine the most vulnerable sections along the studied reaches to such behaviour, which are phenomena entailing hydraulic, ice morphology and fluvial geomorphology. A geospatial model clusters hydraulic characteristics (e.g. discharge or stage), ice characteristics (e.g. ice thickness and ice type) and river geomorphological characteristics (e.g. sinuosity, slope, width, etc.) into common river features called Geomorphic Response Units (GRU). A statistical clustering technique such as principle component analysis (PCA) is used to derive these GRUs. It is assumed that certain GRUs will be more susceptible to certain ice cover behaviour, such as breakup and jamming of river ice. Data acquired along the Slave River and its delta in Canada is used to test the geospatial model. The main data sources are space-borne remote sensing MODIS imagery and traditional and local knowledge from members of the communities alongside the river, in particular Fort Resolution and Fort Smith
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    A GIS-Based emergency response and management support framework for Earthquake crisis: A case study of Antakya and Kahramanmaras earthquake in Turkey
    (Elsevier, 2024) Hamad Hassan Awan, Marzhan Kabdrakhmanova, Huseyin Atakan Varol, Ferhat Karaca
    Earthquakes can cause significant damage, including loss of lives, collapsed buildings, and blocked roads. However, the severity and frequency of earthquakes cannot be accurately predicted. To mitigate these effects, successful disaster management, particularly in improving post-earthquake road network connectivity, is crucial. Therefore, this study presents a novel satellite imagery-based approach for identifying post-earthquake road blockage and to assess its impact on urban infrastructure and emergency response management. This study utilised real-world pre- and post-earthquake satellite images of the earthquake that struck Turkey on February 6, 2023 using ArcGIS Pro. The results demonstrated that in the scenario when people in affected areas (incidents) tried to escape to emergency gathering zones, out of the initial 126 incident locations in Antakya, 101 of them experienced alterations in the selected routes after the earthquake. In Kahramanmaras, out of 35 incidents, 28 experienced changes in the selected routes. In the case of emergency vehicles (firefighting, medical aid, etc.) traveling to affected areas, some emergency vehicles were assigned a great number of incidents, whereas some vehicles had no incidents assigned to them. The findings of this study suggest that the developed framework can identify road blockage and inefficiencies in an emergency response framework with high accuracy. Therefore, the approach presented in this paper can be implemented to develop a practical geographic information system (GIS) based model to enhance the emergency response management for potential future earthquakes. Thereby, this study can facilitate the level of resilience of urban environments to withstand and adapt to future crises.
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    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.
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    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, Chau
    Deploying 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 applied
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    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, Zhumabay
    A 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.