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PHYSICAL LAYER SECURITY USING MASSIVE MIMO AND RIS TECHNOLOGY
No full textMassive Multiple-Input-Multiple-Output (MIMO) systems and Reconfigurable Intellegent Surfaces (RIS) are considered to be the key technologies for next generations wireless communication, which are aimed to achieve higher data rates, massive connectivity and more secure data transmission. Combined use of these technologies together with artificial noise (AN) gives high hopes for strengthening Physical Layer Security (PLS) in wireless
networks. This capstone work considers configuring phase shifts of RIS such that the impact of AN is maximized for illegitimate user, while its impact on legitimate user is not
significant compared to the actual signal received from base station. In the proposed system model, some antennas is dedicated for AN and the rest are transmitting the actual data. The main objective of this model is to maximize Secrecy Capacity (SC) of the communication link, while satisfying the users’ quality of service (QoS). To achieve that, we optimize the phase shifts of RIS and find the optimal number of base station antennas transmitting AN. Obtained results validate theoretical concepts and show that proposed RIS-assisted Massive MIMO incorporated with AN transmission can be an effecting tool
for establishing and improving PLS in wireless communication
DIETARY PATTERNS OF ELDERLY INDIVIDUALS WITH AND WITHOUT ALZHEIMER'S DISEASE IN KAZAKHSTAN: A COMPARATIVE STUDY OF NUTRIENT INTAKE, FOOD GROUPS, AND OVERALL DIETARY QUALITY
No full textAlzheimer's disease (AD) is the leading cause of mortality and disability in the elderly population worldwide. While various factors contribute to AD development and progression, the role of dietary patterns, particularly in under-studied regions, remains unclear. This study analyzed the dietary intake of individuals over 50, with and without AD, in Kazakhstan to determine nutritional differences and associations with AD.
A cross-sectional study was conducted among AD and age-matched controls in Astana and Almaty. Dietary intake was assessed using a food frequency questionnaire. Nutrient intake was analyzed for macronutrients and micronutrients.
No significant differences were observed between the nutrient intake of AD participants between cities, suggesting uniform dietary patterns among the population with AD within Kazakhstan. Furthermore, macronutrient intake revealed no differences between AD and control. Variations were observed between AD and control in micronutrients. AD participants had lower nutrient intake values in both cities, consistent with previous reports of decreased appetite and swallowing difficulties in AD patients.
Our findings suggest that micronutrient intake may have neuroprotective effects in the Kazakhstani elderly population and warrants further investigation. The observed differences in micronutrient intake between AD and control groups could inform targeted nutritional interventions to prevent or mitigate AD progression in this region
DECRIMINALIZATION OF DOMESTIC VIOLENCE: PERSPECTIVE OF EXPERTS AND PUBLIC OPINION IN KAZAKHSTAN
No full textThis study aims to shed light on the decriminalization of domestic violence in Kazakhstan, specifically exploring the perspective of non-governmental experts and public opinion. Using a mixed-methods approach, 254 survey responses were collected from the residents of Astana, and seven interviews were conducted with experts. The results of the logistic regression analysis revealed that younger age respondents, females, not married and without children were more likely to support the measure that domestic violence should be criminalized. Our findings suggest that under decriminalization the absence of adequate punishment and protective tools for victims are critical issues since they may send the wrong signal to society and unleash the hands of the aggressors. Another issue with decriminalization is that it creates issues of impunity which later breeds violence. Although domestic violence was criminalized in Kazakhstan before 2017, it was not implemented in practice properly. Victims lacked the legal tools and resources to protect themselves. As claimed by the study respondents, a legal approach is necessary but not enough because the issue of domestic violence requires a multifaceted approach. Necessary steps may include social changes such as fighting against gender-based discrimination and gender inequality, changing the deeply-rooted patriarchal norms, and inculcating a culture of zero tolerance towards domestic violence. Further detailed recommendations based on the responses of experts and best practices for handling domestic violence around the world are provided
"A ROSE BY ANY OTHER NAME WOULD SMELL AS SWEET": RETHINKING THE IMAGERY OF THE ROSE IN SHAKESPEARE'S SONNETS
No full textShakespearean sonnets have myriads of symbols threading from one to another. Rose and canker, young man and dark lady, time, seasons, flowers - these are just a few of the numerous symbols Shakespeare uses in them, narrating a story of love and praise and life. Rose appears to be one of the most prominent of them, making people all over the world question: what could it mean? The most popular theory states that rose indicates sublime beauty and eternal youth and passionate love for the beloved. Rather than a symbol of poetical romance, I think that the rose imagery bears much more than that. This capstone argues that the rose is the representation of the poet himself, the marker of author's presence in own works, and that through the rose Shakespeare talks and devotes the sonnets' lines to himself delivering deep self-reflecting messages. The study of Shakespeare's sonnets is broad and well-researched. Yet, it somewhat lacks the variety in interpretation of the rose imagery. My project could contribute to widening this variety, proposing the new alternatives for the floral symbolism. This capstone project applies close reading of Shakespeare's sonnets, complemented by the historical, biological, psychological, and literary theories to disclose the imageries and elaborate their messages. The Shakespearean scholars' works will also be used to compare and contrast the interpretations of the rose.
The analysis of the sonnets explores three main symbolic images that are mirror glass, rose, and rosewater, each of which complements each other. Mirror establishes the connection between the author (the addresser) and the "beloved" (the addressee) in a way that both addresser and addressee are demonstrated as the same person talking to himself in a reflection. The rose, which is used by the author as an almost a synonymic reference to the addressee, is observed. Rose here will be examined as the symbol of the author - it grows, it lives, ages and decays, bearing the beautiful virtues within and suffering from the canker of the humane vices. Finally, the rose remains the rose even after decay. It is distilled into the third symbol, that of fragrant rosewater, which reminds the people of the beauty and youth of the flower, just like the poet is distilled into the black ink on the paper which is saved as a poetic legacy for future generations. Shakespeare the Rose lives eternally in his sonnets up until our days, being the same old beautiful man he once was back then
ANALYSIS AND OPTIMIZATION OF TRANSPORT AND REACTION PROCESSES IN THE CYLINDRICAL FLOW-THROUGH CATALYTIC MEMBRANE REACTORS
No full textCylindrical flow-through catalytic membrane reactors, employing porous membranes impregnated with catalysts, offer enhanced selectivity and yield in chemical reactions. This work is focused on mathematical modeling and numerical analysis of a cylindrical flow-through catalytic membrane reactor. The reactor's geometry, which incorporates a porous membrane, is specially tailored for the cylindrical configuration, addressing a research gap in realistic geometries. The proposed mathematical model includes a series of irreversible reactions with power-law kinetics occurring under non-isothermal conditions. A system of non-linear diffusion-convection-reaction equations is formulated for a cylindrical catalytic membrane reactor under both steady and unsteady-state. The study investigates the occurrence of dead zones within the membrane reactor as a result of rapid reactant depletion, a phenomenon that has not been extensively studied in prior literature for cylindrical membrane reactors. Problems with fractional reaction exponents require efficient numerical solvers since conventional iterative solvers encounter difficulties due to the fact that the power-law reaction term with fractional reaction exponent is not differentiable at the vanishing concentration. A novel time-marching scheme specifically designed for the cylindrical catalytic flow-through membrane reactor is developed and applied for simulations to get valuable insights into dead-core phenomena. The effects of dimensionless process parameters such as Thiele modulus, mass Peclet number, heat Peclet number, etc. and a model parameter (i.e., geometry parameter) on the concentration and temperature profiles, as well as dead-zone formation, are extensively investigated under steady-state. The simulation results demonstrate that these parameters affect the occurrence of dead zones and their size. The impact of convective flow on the reactor performance indicators under steady-state is also presented. Moreover, the investigation extends to unsteady-state conditions, exploring the dynamic behavior of concentration and temperature profiles as well as productivity under both isothermal and non-isothermal scenarios. In the case of a single reaction, the analysis of productivity reveals substantial percent increments, offering insights into the identification of optimal conditions. Finally, a comprehensive exploration into the optimal conditions for productivity in a sequential reaction is conducted
A PSC-OPV DUAL-SOURCE ENERGY HARVESTING SYSTEM DESIGN
No full textPower management integrated circuits in photovoltaic (PV) energy harvesting applications require an effective “maximum power point tracking (MPPT) algorithm” for optimizing PV power generated in the face of constantly changing climatic conditions. Photovoltaic cells are attractive because they are widely available indoors and outdoors and depend on radiative energy transmission. An additional benefit is their ability to be effortlessly integrated into device designs. Indoor Photovoltaic (IPV) devices harvest electricity from indoor lights without emitting greenhouse gasses.
The PV output voltage suffers from non-linearity, making it difficult to connect directly to the load. Fortunately, this issue can be solved by incorporating an MPPT algorithm into the system. Also, the connected load requires a voltage higher than the generated voltage from the PV. A dc-dc boost converter that increases the generated voltage to the required voltage was designed.
This research work developed a CMOS-based integrated power management system that comprises two photovoltaic energy harvesters as input with their individual MPPT to power IOT and smart electronic devices. Ripple Correlation Control (RCC) and perturb and observe (P&O) algorithms for optimizing power extraction from a perovskite solar cell (PSC) and Organic photovoltaics, respectively, were designed. The two MPPTs produced a desirable duty cycle, which was able to drive the boost converter to produce an output voltage of 4.16V and 6.45V from an input voltage of 1V and 1.2V with a power efficiency between 90% and 97.7%. The system was designed using UMC180nm CMOS technology
EXPERIMENTAL & NUMERICAL MICRO-EDM SURFACE TREATMENTS OF NEW GENERATION TITANIUM BIOMEDICAL ALLOYS
No full textDespite advancements in material science, biomedicine, and orthopedic implant applications continue to encounter numerous challenges. The prevalence of implant failures in long-term applications serves as a significant motivation for ongoing research aimed at reducing the likelihood of such failures. Titanium and its new-generation alloys are widely employed in high-end applications due to their special properties, such as corrosion resistance, biocompatibility, Young’s modulus, and strength-to-weight ratio. This unique blend of qualities positions titanium alloys as highly sought-after materials in sectors, such as biomedical, aerospace, automotive, sports equipment, etc. Modern industries frequently use micro–Electro micro-electro-discharge machining (μ-EDM), a non-conventional machining technique that is especially useful for processing hard materials like titanium alloys. μ-EDM can produce intricate shapes with excellent dimensional precision. The main emphasis of this work is an experimental analysis of the μ-EDM of TNZT alloys employing a tungsten carbide (WC) electrode. The results for micro-EDM of Ti-35Nb-7Zr-5Ta showed that with the increase in process parameters capacitance (C) from 10nF to 100nF at Voltage (V) 80V, the machining performance parameters such as material removal rate (MRR), overcut (OC), crater size, surface microhardness, surface roughness, and crater size increase by 6.38, 1.523, 4.496 1.069, and 1.803 times respectively. However, the circularity of the µ-hole decreases by 1.099 times. This study intends to show how the two key machining factors (C & V) influence significant machining performance parameters. The influence of capacitance on machining performance variables is more dominant.
Additionally, this study introduces an analytical model rooted in electro-thermal theory to estimate the size of micro-craters in micro-electrical discharge machining (μ-EDM). Addressing the challenge of the stochastic nature of the μ-EDM process, the model incorporates voltage and capacitance to predict crater size on the workpiece caused by individual discharges in micro-EDM. The simulation involved using COMSOL Multiphysics 5.6 software to simulate a single discharge in the μ-EDM process. This simulation accounted for the phase change material properties and the expansion of the plasma channel radius over time. The study further developed a numerical analysis to assess how input parameters (capacitance and voltage) influence the efficiency of the plasma channel in removing molten material. A regression model for plasma flushing efficiency (PFE%) based on experimental and numerical results was introduced to predict the actual crater size. The findings indicate contrasting effects of capacitance and voltage on plasma flushing efficiency. Specifically, an increase in capacitance contributes to an increase in plasma flushing efficiency
DESIGN OF A 7-STORY HOTEL WITH A BASEMENT IN OXNARD, CA, USA
No full textThe following Capstone project displays a design from scratch proposed for a 7-story
Hotel building with a Basement in Oxnard, California, US. Hereinafter, named as ‘élite’. The
design process encompasses -four major engineering modules: Architectural/Structural,
Geotechnical, Environmental, and Construction Management. Detailed calculations and design
warranting structure’s vigorous stability of reinforced concrete frame in the presence of intense
wind and seismic loads were conducted in the Structural part comprising 31% of the project.
With a 34% share, the geotechnical component is crucial to the stability of the hotel in an
earthquake-prone area because it focuses on foundation design and soil studies conducted in
California. The strategies of handling Municipal Solid waste during the construction process and
design life along with generation rates for the corresponding Hotel industry were revised in a
detailed manner in the Environmental part of the report, correspondence of which to the project
is 15%. Last but not least, the 20% of the project that is dedicated to Construction Management
includes comprehensive planning, from project charter to risk management, to guarantee a
smooth and efficient building process.
The selection of Oxnard, a city with the required facilities and services, raises the hotel's
allure to travelers. The hotel's proximity to Los Angeles and the natural wonders of the area
make it an attractive business opportunity. Given Oxnard's natural characteristics as an
earthquake zone and high wind speeds, the design of the climate-responsive architecture was the
main concern. The project emphasizes high-quality materials and building techniques to create a
firm, lifelong, and ecologically sustainable structure. The design procedures complies with the
California Building Code and ASCE 7-10 standards
TRANSITION FROM SECONDARY SCHOOL TO HIGHER EDUCATION: EXPLORING THE EFFECTIVENESS OF ENGLISH PRIVATE TUTORING, AND ITS IMPLICATIONS IN KAZAKHSTAN
No full textSince the beginning of 21st century, Private tutoring (PT) has grown significantly in popularity and prevalence. However, English private tutoring (EPT), a subcategory of PT, remains a relatively under-researched area, with limited empirical studies on EPT in Central Asia, including Kazakhstan. Therefore, this qualitative study aims to fill this gap by examining the EPT experiences of undergraduate students from Kazakhstan as they prepared for their high-stakes university entrance exams. Drawing on Benson’s (2011) four-dimensional model of language learning beyond the classroom, the study addresses two research questions: 1) How were the four dimensions (location, formality, locus of control and pedagogy) interpreted in the participants’ EPT experiences? 2) What are the participants’ views about the future of PT in Kazakhstan? The data were gathered from eight undergraduate students enrolled in a highly selective Kazakhstani university where English was used as the medium of instruction (EMI). This study utilized two qualitative research methods: narrative writing and individual semi-structured interviews. The findings of the study revealed that regarding the location of EPT, most participants preferred small group tutoring. Concerning the formality, the participants articulated the positive, indirect involvement of their parents and hiring a private tutor for their children as a means to relieve the burden on their shoulders as ‘responsibilized’ parents. Regarding the locus of control, the participants took EPT to enhance their chances of a place at one of the prestigious EMI universities. Participants admitted that they could not secure a place at that EMI university without having EPT. However, they articulated some disadvantages of EPT. The study’s findings have led to suggestions for pedagogical improvements and identified areas for future research, including the
adoption of effective procedures to enhance fair access to highly selective universities and regulate the PT market in Kazakhstan and other regions.
Keywords: Private tutoring, English private tutoring, higher education, Central Asia, qualitative stud
REMEDIATION OF PETROLEUM CONTAMINATED SOILS BY POLYMER SOLUTIONS
No full textThis study employs computational fluid dynamics (CFD) simulations to assess the efficacy
of polymer solutions in remediating petroleum-contaminated soils. Focused on the interaction
between polymer solutions and soil contaminants at the Darcy scale, the research navigates
through the complexities of soil pollution and the potential of polymers for environmental cleanup.
Our exploration is rooted in a computational model, acknowledging its simplification of real-world
dynamics yet providing pivotal insights into the remedial capabilities of polymers.
In this study, computational simulations serve as a lens to examine the 'fingering effect'—
a significant obstacle in the fluid dynamics of soils that complicates the process of remediation.
By modifying variables like viscosity, interfacial tension (IFT), density, and injection velocity, the
aim is to identify the most favorable conditions under which polymer solutions can efficiently
displace Light Non-Aqueous Phase Liquids (LNAPLs).
Key results demonstrate that reducing the IFT between the injected fluid and the dispelled
fluid can enhance displacement efficiency by 1-2% saturation beyond baseline conditions observed
in case studies. Moreover, optimizing the injected fluid's viscosity to 0.007 Pa·s markedly
improves the dispelled fluid displacement, achieving a 96% effectiveness—a 6% increase
compared to the case study baseline. Additionally, adjusting the injection velocity to 0.3∙ 10−4m/s
further optimizes the displacement process, albeit with considerations for increased operational
costs and the need for a balanced approach to achieve economic and environmental sustainability.
A key discovery was that reducing the IFT between the injected and dispelled fluid
enhanced the displacement efficiency of LNAPLs by an additional 1-2% saturation over baseline
conditions. Furthermore, optimizing the viscosity of the injected fluid to 0.007 Pa·s significantly
bolstered LNAPL displacement, achieving an unprecedented 96% effectiveness. This constitutes
a 6% improvement from the baseline effectiveness observed in prior case studies. However, the
study also outlines the inherent challenges and costs associated with increasing fluid viscosity,
such as the need for higher injection pressure and the potential for extended project timelines