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Acoustic emission based health monitoring of RC corroded beams strengthened by CFRP anchorage system under bending loads
No full textThis study explores the damage evolution and crack behavior exhibited by CFRP-strengthened corroded RC beams subjected to bending loads, with the application of AE monitoring. The results show that three primary failure modes were observed: concrete cover separation, debonding of the CFRP sheet with anchor pullout and matrix cracking and fiber tearing, with the middle mode exhibiting greater ductility. AE ringing counts analysis effectively divided the damage process into three stages: initial damage, damage development, and continuous damage. Signal intensity analyses provided insights into damage severity, revealing enhanced crack propagation in corroded beams, while severe corrosion reduced AE signal frequency and intensity in later stages, indicating initial crack activity inhibition and accelerated damage in mild to moderate corrosion. The Ib-value demonstrated trends in ductility and damage severity, with higher ductility in less corroded beams and restricted damage development in heavily corroded ones. RA-AF crack classification and Gaussian Mixture Clustering identified an increased proportion of shear cracks with higher corrosion levels, reducing shear load-carrying capacity. These findings highlight AE-based monitoring as an effective tool for real-time damage assessment in CFRP-strengthened RC beams
Discourses on megaprojects and urbanism in the Turkish Republic: An analysis of Atatürk Forest Farm and Canal Istanbul
No full textCreatinine-on-a-chip: colorimetric ELISA-based serum creatinine detection in a microfluidic device
No full textChronic kidney diseases (CKDs), which often end in kidney failure for many people around the world, have an important place in public health given that they also trigger other diseases. Therefore, the development of fast and cost-effective diagnostic technologies enables effective monitoring of patients and early diagnosis. Here, using the Enzyme-Linked Immunosorbent Assay (ELISA) principle, serum creatinine concentrations were determined using the developed lab-on-a-chip (LOC) platform. In this system, which was termed “creatinine-on-a-chip”, colorimetric ELISA protocol was applied to determine creatinine levels in a microfluidic chip functionalized with creatinine-specific antibodies. Creatinine detection was performed by quantifying the absorbance difference between the detection and reference channels, normalized to the reference signal within the microfluidic chip. The detection signal intensity varied depending on the region selected along the microfluidic channel. The adsorption of the capture antibody used for surface functionalization, which was particularly more pronounced near the inlet region, played a critical role in the detection signal. These findings suggest that random selection of the detection area can lead to significant signal variability, and that careful selection of a well-characterized region is essential for improving detection performance. With this developed system, creatinine was detected with high sensitivity in the linear range of 1-20 μg mL−1, both spiked in phosphate buffered saline (PBS) and fetal bovine serum (FBS). Using the creatinine-on-a-chip, serum creatinine analysis can be performed rapidly (∼15 min) in a cost-effective manner ($1.05 per test)
CFD Coupled With a Lognormal Model for Modeling an Evaporation-Condensation Type Aerosol Generator
No full textIII-Vsemiconductors are among the most versatile materials for optoelectronic andphotonic applications due to their air stability and tunable direct bandgaps,which span a wide range from 0.35 to 6 eV. Gas-phase synthesis offers apromising approach for producing ligand-free III-V nanocrystals, an essentialfeature for electronic applications. However, most gas-phase methods rely onvapor-phase precursors, which are expensive, highly toxic, and pyrophoric. Analternative involves generating elemental precursors using anevaporation-condensation generator (ECG), commonly implemented as a tubularfurnace. Developing an ECG capable of delivering a stable aerosol output withhigh mass yield is a critical need.Inthis study, mathematical modeling and simulations of an ECG were performed byintegrating momentum, heat, and mass transport with aerosol dynamics. Antimony,a key component of various III-V compounds, was selected as the test material.Building on experimental results for an ECG operating under reduced pressure,simulations were conducted at 6 Torr across varying gas flow rates usingcomputational fluid dynamics (CFD). Once the transport phenomena were modeled,a detailed lognormal aerosol dynamics model was developed, incorporating termsfor advection, surface growth, diffusion, coagulation, and thermophoresis.These terms were integrated into the CFD framework to achieve a comprehensivemathematical representation of aerosol formation. The results, includingaerosol mass flow rates and generator yields, demonstrated anorder-of-magnitude agreement with experimental data, validating the model'saccuracy. Details of the CFD and lognormal model will be presented, along withresults and comparison with experimental data.</p
32-bit and 64-bit CDC-7-XPUF Implementations on a Zynq-7020 SoC
No full textPhysically (or Physical) Unclonable Functions (PUFs) are basic and useful primitives in designing cryptographic systems. PUFs are designed to facilitate device authentication, secure boot, firmware integrity, and secure communications. To achieve these objectives, PUFs must exhibit both consistent repeatability and instance-specific randomness. The Arbiter PUF (APUF), recognized as the first silicon PUF, is capable of generating a substantial number of secret keys instantaneously based on the input, all while maintaining a lightweight design. This advantageous characteristic makes it particularly well-suited for device authentication in applications with constrained resources, especially for Internet-of-Things (IoT) devices. Despite these advantages, APUFs are vulnerable to machine learning (ML) attacks. Hence, those APUF designs were improved to achieve increased resistance against such attacks while maintaining usefulness and efficiency for IoT applications, and Component-Differentially Challenged XOR Arbiters (CDC-XPUFs) were proposed. In this work, ML-resistant 32-bit and 64-bit implementations of the Component-Differentially Challenged XOR Arbiter PUF with 7-stream (CDC-7-XPUF) are carried out. These CDC-7-XPUFs are evaluated using PUF metrics from the literature, and the resource utilization ratios of both implementations are also presented. The implementation setup contains the ZC702 Rev1.1 Evaluation Board, featuring the Xilinx Zynq-7020 SoC, and utilizes a configuration involving three boards for experimental validation
ODTÜ Endüstriyel Tasarım Bölümü Mezuniyet Projeleri Kataloğu 2025 / METU Department of Industrial Design Graduation Projects Catalogue 2025
No full textRivers Solomon’s An Unkindness of Ghosts: Cruel Optimism and Meritocracy in an Engendered Critical Dystopia
No full textSearch for jet quenching with dijets from high-multiplicity pPb collisions at = 8.16 TeV
No full textThe first measurement of the dijet transverse momentum balance xj in proton-lead (pPb) collisions at a nucleon-nucleon center-of-mass energy of = 8.16 TeV is presented. The xj observable, defined as the ratio of the subleading over leading jet transverse momentum in a dijet pair, is used to search for jet quenching effects. The data, corresponding to an integrated luminosity of 174.6 nb−1, were collected with the CMS detector in 2016. The xj distributions and their average values are studied as functions of the charged-particle multiplicity of the events and for various dijet rapidity selections. The latter enables probing hard scattering of partons carrying distinct nucleon momentum fractions x in the proton- and lead-going directions. The former, aided by the high-multiplicity triggers, allows probing for potential jet quenching effects in high-multiplicity events (with up to 400 charged particles), for which collective phenomena consistent with quark-gluon plasma (QGP) droplet formation were previously observed. The ratios of xj distributions for high- to low-multiplicity events are used to quantify the possible medium effects. These ratios are consistent with simulations of the hard-scattering process that do not include QGP production. These measurements set an upper limit on medium-induced energy loss of the subleading jet of 1.26% of its transverse momentum at the 90% confidence level in high multiplicity pPb events
CHALLENGING PATRIARCHY: THE ACCUMULATION AND TRANSFORMATION OF CAPITALS AMONG RUSSIAN MARRIAGE MIGRANTS IN TURKEY
No full textElectrochemical Sensors for Rapid Cardiovascular Disease Diagnostics
No full textCardiovascular diseases (CVDs) remain a leading cause of death, particularly in developing countries, where their incidence continues to rise. Traditional CVD diagnostic methods are often time-consuming and inconvenient, necessitating more efficient alternatives. Rapid and accurate measurement of cardiac biomarkers released into body fluids is critical for early detection, timely intervention, and improved patient outcomes. Electrochemical methods offer a robust solution by enabling rapid, sensitive, selective, and multiplex detection of CVD biomarkers, paving the way for early diagnosis and treatment advancements. This review highlights the performance and potential of electrochemical sensors for detecting specific CVD biomarkers and related organic molecules. It explores electrochemical sensing mechanisms, their evolution, the integration of nanotechnology, and diverse sensing platforms. It also examines emerging technologies such as microfluidic, smartphone-integrated sensors, and microneedle- and tattoo-based sensors. Challenges and opportunities in integrating electrochemical sensors into point-of-care (POC) and wearable devices are discussed. Finally, the review compares commercial CVD sensors with existing methods and outlines future directions to advance the field