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SIMULATOR FOR TIME-SLOTTED LORA NETWORKS
No full textA new simulator for evaluating Time-Slotted (TS) LoRa networks is presented. Traditional testing limitations, due to node scarcity, are overcome by enabling virtual analysis under diverse conditions. The simulator features optimized code, removes unnecessary phases, and implements a dynamic retransmission policy with Reinforcement Learning for improved performance. This user-configurable tool empowers researchers to explore TS-LoRa behavior and optimize this emerging technology
OPTIC NERVE ULTRASONOGRAPHY FOR DETECTING INTRACRANIAL PRESSURE IN PATIENTS WITH CEREBROVASCULAR DISEASES: A SYSTEMATIC REVIEW
No full textIntroduction: Ultrasonography shows potential as a diagnostic method for identifying intracranial hypertension. Nevertheless, its diagnostic performance in measuring optic nerve parameters remains ambiguous. To address this uncertainty and assess its significance in clinical practice, a systematic review of the literature was conducted.
Methods: A systematic search was carried out across PubMed, Google Scholar, and the Cochrane Library databases. The quality of evidence was evaluated utilizing the Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology, while the risk of bias was assessed using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) checklist.
Results: 507 records were identified, following the removal of 499 records, 8 observational studies remained for final review covering 329 participants. The reported diagnostic accuracy of ultrasonography ranged between 58.8% to 100% concerning sensitivity, 67% to 100% for specificity, 43.5% to 100% for positive predictive values (PPV), and 50% to 100% for negative predictive values (NPV).
Conclusion: The literature suggests that ultrasonography demonstrates comparable accuracy to reference computed tomography in measuring the optic nerve, but depends on the expertise of the sonographer. Further investigation is required to fully understand its diagnostic performance
OPTIMIZATION OF COAT-HANGER DIE USING 2-WAY FSI AND ADJOINT METHOD
No full textThe coat-hanger dies are extensively utilized in the plastic film and sheet extrusion sector. The product's quality and the extrusion machine's power requirements are contingent upon the flow uniformity at the die exit and the amount of pressure drop, respectively. Designing a die that can provide uniform flow at the die exit and minimize pressure drop is challenging for die manufacturers. This study investigated the die utilized by a local polypropylene sheet manufacturer. It enhanced the die's design regarding deflection at the exit, uniformity of outlet velocity, uniformity of shear rate at the walls, and pressure drop. This was achieved by employing Scheme Programming Language and the licensed CFD package, Ansys FLUENT Workbench 2020 R2, based on the finite element method. The rheological characteristics of the polypropylene were characterized using the Power law, Cross law, and Carreau-Yasuda viscosity model. The FSI analysis results indicate that by raising the die body thickness to 100mm and reducing the number of supports to 4, the deflection at the exit is reduced to 1.03%. Furthermore, the analysis of the simulation results acquired using the adjoint optimization method showed that the optimized die design outperforms all three aspects by ensuring uniform exit velocity, wall shear rates, and reduced pressure drop
TIME SERIES FORECASTING METHODS FOR SOCIO-ECONOMIC INDICATORS: A CASE STUDY OF KAZAKHSTAN
No full textThis study compares traditional statistical methods (ARIMA, ETS) with LSTM, a deep learning approach, to forecast key socio-economic indicators (GDP, Population Growth, Price Index, Income per Capita, Housing prices) in Kazakhstan. Using historical data from the Bureau of National Statistics, the models are trained and evaluated using metrics MAE, MAPE and RMSPE. The research aims to understand the strengths and limitations of each method in the context of Kazakhstan's socio-economic data, providing insights for future forecasting in the region
THE MEANING OF RELIGIOUS VEILING IN POST-SOVIET KAZAKHSTAN.
No full textFollowing the collapse of the Soviet Union, citizens in former Soviet Republics embarked on a profound "quest for identity," leading to the emergence of various religious and political groups, particularly in Central Asian states. Since the 1990s, there has been a noticeable rise of Islamic groups and an overall Islamization of society in these regions, characterized by an increase in veiled women, bearded men, mosques, and madrasas. The phenomenon of the quest for identity in former Soviet Central Asian Republics to an extent followed the flow of a broader revival of religion witnessed in Muslim-majority states like Turkey, Egypt, and Iran. The focus of this capstone project is to explore and elucidate the significance of veiling among women in post-Soviet Kazakhstan, examining the reasons behind veiling, societal and state responses, and the diverging interpretations between state agendas and individual meanings attributed to veiling. This discrepancy sheds light on the complex interplay between state policies, cultural practices, and personal interpretations of veiling
INFLUENCE OF FREEZE-THAW CYCLES ON THE MECHANICAL CHARACTERISTICS OF SAND REINFORCED WITH CSA CEMENT AND POLYPROPYLENE FIBER
No full textEarth structures like rail and roads are undergoing recurring freeze-thaw cycles in regions with seasonal variation. Most issues related to these structures originate from the limited scope of design guidelines, which solely focus on strength and spurn long-term stability and durability considerations. The soil stabilization approach can be applied to enhance the properties of the soil. Ordinary Portland cement (OPC) is frequently used for these applications. OPC cement emits considerable carbon dioxide, even though it is an excellent binding material. One possible substitute for OPC is calcium sulfoaluminate (CSA) cement. This investigation aims to determine the consequence of cyclic freeze-thaw action on the sample treated with CSA cement and fiber. Samples were prepared using 3% and 5% CSA cement with 0, 0.25%, 0.5%, 0.75%, and 1% polypropylene fiber (PPF) and then subjected to 0, 1, 3, 5, and 7 F-T cycles after 3, 7, and 14 days of curing period. UCS and UPV tests were conducted to monitor the change in soil strength by increasing the fiber content under F-T cycles. The results demonstrated that the optimum fiber content can vary for different cement ratios, and excess may have a negative impact on strength development. The UPV value increases with a rise in fiber content until the optimum value. For soil stabilized with 3% CSA cement, the UCS strength increases with fiber content up to 1%; however, with 5% CSA cement content, the UCS strength first increases with 0.25% of fiber, followed by a decrease in strength. After F-T cycles, a considerable decrease in strength was observed for soil samples without fiber reinforcement, as compared to fiber-cement-stabilized samples. The influence of fiber content and F-T cycles on soil structure was also determined by scanning electron microscopy, which shows that the void and pores are the reasons behind the decrease in strength. The study aims to contribute to creating more enduring and environmentally friendly construction techniques by offering insightful information about how these composite materials behave when cold outsid
COMMUNICATION DEVICE FOR DEAFBLIND
No full textContext/background: The tactile language-generating device is a technology designed to help deafblind individuals communicate. Deafblindness is a condition in
which an individual has both hearing and vision impairments. It is estimated that
there are over 6 million people globally who are deafblind. This condition poses
significant challenges to communication, access to information, and social inclusion.
The development of the tactile language-generating device aims to address some of
these challenges by providing an alternative means of communication for deafblind
individuals.
Sources consulted: To gather information on the tactile language-generating device for deafblind people, various sources were consulted. These sources included
academic journals, conference proceedings, patents, and news articles. Some of the
key sources consulted were the Journal of Visual Impairment & Blindness, the International Journal of Human-Computer Interaction, the Journal of Rehabilitation
Research and Development, and the US Patent and Trademark Office.
Key concepts: The key concepts in the development of the tactile language-generating
device include: Australian Tactile Sign Language (ATSL) is a form of sign language
that is specifically designed for communication with people who are deafblind. ATSL
uses a combination of hand signs and tactile signals to convey meaning. It was developed in the 1980s and 1990s in Australia and is now used in several countries
around the world. Vibrational motors are a common form of tactile feedback used
in many tactile language-generating devices. These motors generate vibrations that
can be felt by the user, providing a tactile representation of the spoken words or text
being converted. Vibrational motors can be used to generate different types of tactile
signals, such as buzzing, pulsing, or tapping. Tactile feedback: This refers to the use
of touch to provide feedback to the user. The device uses various tactile sensations to
communicate different types of information. Text-to-tactile conversion: This is the
process of converting written text into tactile information. The device uses various
techniques, such as Braille, vibration, and pressure, to communicate written text to
the user.
Data sources and collection methods: Data sources for the development of the
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tactile language-generating device included surveys, interviews, and user testing. Surveys and interviews were conducted with deafblind individuals to understand their
communication needs and preferences. User testing was conducted to evaluate the
effectiveness and usability of the device.
Main methods used: The main methods used in the development of the tactile
language-generating device include:
User-centered design: The development of the device was guided by user-centered
design principles, which involved involving deafblind individuals in the design process
and incorporating their feedback into the final product.
Results/current state-of-the-art: The development of the tactile language-generating
device is still ongoing, and several prototypes have been developed. These prototypes
have shown promising results in enabling deafblind individuals to communicate more
effectively. Some of the features of the device include text-to-tactile conversion, and
the ability to connect to other devices such as smartphones and computers.
Conclusions: The tactile language-generating device has the potential to transform
the lives of deafblind individuals by providing them with an alternative means of communication. The device is in the testing and improvement stage, and more research
is needed to improve its effectiveness and usability. Overall, the use of vibrational
motors in tactile language-generating devices has great potential to improve communication for people who are deafblind or have other sensory impairments. With
further research and development, it may be possible to create even more effective
and intuitive tactile communication systems
ROLE OF HUMAN NEI-LIKE DNA GLYCOSYLASES IN DNA REPAIR AND CANCER RESISTANCE
No full textIndividuals presenting with non-resectable and rapidly metastasizing tumors, including but not limited to breast and lung cancers, are commonly managed through the synergistic application of multi-agent chemotherapeutic regimens and ionizing radiation therapy. Chemotherapy and radiation therapy cause a type of DNA damage known as complex DNA damage (CDD). This includes large DNA adducts, links between DNA strands (interstrand DNA crosslinks), and clustered lesions, which are groups of damage that include double-strand breaks (DSBs). These complex damages are more intricate in their structure compared to individual, isolated lesions. (1).
Although CDDs constitute the minor proportion of total DNA damage that most anticancer agents inflict in cellular environments, its cytotoxicity is pronounced if left unrepaired. Whilst the sensitivity of cancer cells to chemotherapy and radiotherapy is usually acquired initially, but within three-to-twelve-month time, resistance to these therapies might be developed. Hence, the resistance of tumor cells to therapeutic intervention still largely confines the optimal efficacy of chemotherapy and radiotherapy for advanced cancers. The molecular mechanisms that underpin the intricate resistance in cancer are not fully elaborated. Among potential mechanisms, the activation of DNA repair pathways presents a compelling hypothesis. Importantly, the cross-resistance that tumor cells show with various DNA cross-linking agents after treatment with a single interstrand DNA crosslink-inducing agent would indicate upregulation of a definite DNA repair process on the part of the cells as an integral component of resistance to the cytotoxicity of interstrand DNA crosslinks in DNA (2).
Investigating the molecular mechanisms of DNA damage recognition by repair proteins could enhance our understanding of cellular DNA damage signaling and the coordination of repair processes.
In the present project, we propose to study repair of complex DNA damage in human cancer cells. The project aims to address following questions: (i) Whether there are unidentified repair activities present in cancer cells; (ii) What are the mechanisms of DNA repair coordination in human cancer cells and whether they involve the specific protein-protein interactions, multi-protein complexes and post-translational modifications; (iii) Whether the new post-replicative modification of DNA, discovered recently during our research collaboration, is involved in the removal of complex DNA damage and in the coordination of DNA repair pathways in cancer cells
MANUFACTURING OF ETHANOLAMINE SOLVENT FOR CO2 CAPTURE
No full textHuman activities have led to significant carbon dioxide emissions, triggering global warming and climate change. As a response, the global carbon capture and sequestration market has been growing rapidly. Monoethanolamine (MEA) is widely used for CO2 capture, with the MEA market projected to grow significantly. This project focused on designing an industrial plant for producing MEA through the liquid-phase reaction between ethylene oxide (EO) and ammonia.
The selected conventional manufacturing process involved three plug flow reactors in series to achieve a near-complete conversion of EO and a 73% selectivity for MEA with a 94% purity. Aktobe region was chosen as the location of the plant for its proximity to raw material suppliers and efficient transportation networks. The projected annual production rate was 12,000 tonnes to meet the CIS region's market demand.
The plant design incorporated essential equipment, including major components like reactors, flash separator, distillation column and heat exchanger, as well as minor components such as compressors and storage tanks. Detailed designs for each piece of equipment were made, following established chemical engineering methodologies. A comprehensive sensitivity analysis conducted in Aspen Plus identified the optimal operating conditions, ensuring efficient and reliable plant performance.
Economic feasibility analysis indicated a total initial investment of 10.2 million over 20 years, confirming the project's profitability.
Looking ahead, the project will focus on enhancing product purity from 94% to 99% and reducing production costs. Future steps include recycling purge streams, separating and selling by-products, optimizing operating conditions by reducing pressure from 25 to 20 bar, and improving distillation column efficiency by implementing reactive distillation methods. These measures aim to further refine the production process, increase profitability, and meet higher market standards
AIR-TO-GROUND CHANNEL MODELING FOR UNMANNED AERIAL VEHICLES
No full textThe ‘Air-to-Ground Channel Modeling for Unmanned Aerial Vehicles’ main goal is to develop a precise and reliable model of the communication channel between unmanned aerial vehicles and ground stations. This project will be mainly focused on the extensive research of recent data and channel simulation using MATLAB. The project will analyze different scenarios and characteristics that may have an impact on the proper work of the channel and find ways to overcome those difficulties. These obstacles can be channel fading, polarization, weather conditions, and hard-to-reach locations. The proposed channel modeling can be beneficial in different spheres of life: safety, surveillance, telecommunication, and national priorities. Overall, the project’s main focus will be based on the enhancement of analytical skills in order to select major types of channel modeling and see the advantages and disadvantages of the proposed model. The results can have a positive impact through the contribution to the advancement of UAV technologies