This paper deals with a sensitivity analysis of engineering critical assessment, using a fracture assessment diagram of through-thickens axial flaws on pressure equipment. Basic option calculations are performed per BS 7910, using engineering fracture mechanics principles, followed by the provision of assessment points. For evaluation purposes, arbitrary design properties of pressure equipment and temperature-dependent materials properties were used. Several through-thickness axial flaw sizes were used for critical assessment. Furthermore, the sensitivity of critical assessment is evaluated by varying stress states and material fracture toughness. Finally, the sensitivity analysis shows how axial flaw growth may become critical, or its acceptability, depending on varying stress states and temperature-dependent material properties, on selected pressure equipment.
Attempts to adopt agile practices are challenged by outsourcing and distributed ways of working popularized in the world today. This paper focuses on outsourcing vendors and empirically examines the progress of agile and Scrum adoption in such environments through the case of information technology companies in Bosnia and Herzegovina. Qualitative content analysis was employed to analyze data obtained from 142 professionals from 43 companies, whose clients are located around the globe. The empirical results reveal a fairly good level of agile awareness in the tested community, but also confirm the findings of earlier research that obstacles to implementing Scrum in outsourced projects exist, emphasizing issues originating from distant Product Owners, diminished Scrum Master role, and customer influence. Team self-organization is recognized as the best adopted Scrum practice, while the product backlog definition, Scrum events, and the process managed through excessive meetings are among those that still require significant improvements.
In the study an estimation of the influence of target material type on the penetration capability of the 12.7 mm API-T (armor-piercing incendiary with tracer) projectile is performed. The literature review contains 14 references regarding 12.7 mm ammunition studies. A relatively large number of metallic targets are taken into consideration in a computer simulation that assesses the influence of the target type on the penetration capabilities of the given projectile. By comparing the acquired findings with the data of other authors, the numerical model was first successfully validated. Simulation results indicate that bainitic steels are by far the most resilient steels. Because of their hardness, these steels displayed significant erosion of the penetrator tip and significant projectile fragmentation upon impact. Iron targets, as expected, performed worse than steel targets, with more penetration seen. Mild steel had a significantly deeper penetration compared to armor steel. The performance of other steels employed in the study was comparable. Numerical simulations have shown to be a very effective technique in ammunition and armor design, resulting in substantial time and cost savings (fewer experimental experiments). Furthermore, by utilizing simulations, researchers can estimate certain physical processes that would be challenging to detect in actual testing.
Background: Dental profiling is the process of analyzing teeth to identify a victim or skeletal remains when no antemortem data are available. Using dental profiling techniques, we can determine the age, sex, and population of the individual and gather data about their socio-economic status, personal habits, oral and systemic health, occupation, nutrition, family relationships, and psychological characteristics. Aims: The research aims to gain insights into the diet, health, socio-economic status, and demography of the Late Iron Age inhabitants of Illyrian origin who lived on the Croatian island of Korcula. This will be achieved by analyzing the remains of teeth and jaw bones found in the Kopila necropolis. Material and methods: The research sample comprised 479 permanent teeth and jawbone remains from three tombs that belong to the collection of the Vela Luka Culture Centre on the island of Korcula. The analysis of the teeth included an examination of their morphological and pathological characteristics as well as metric and non-metric variables. Additionally, the stable isotopes of carbon (14C, 13C), nitrogen (15N), and strontium (86/87Sr) were chemically analyzed. Odontometry was used as a metric variable and the Arizona State University Dental Anthropology System (ASUDAS) was used as a non-metric variable to determine sex. Results: The research findings indicate that healthy teeth are present with a frequency of dental caries of 5.85% and tooth wear of 85.18%. There is morphological atypicality in the number of roots of the upper premolars and taurodontism in the molars. Stable isotopes of carbon and nitrogen show values of d 13C = -19.5 (±0.1) and d 15N = 8.6 (±0.1). The ratio 13C/15N is 3.4. The values of 87Sr/86Sr in the dental enamel are 0.7084000.708433, whereas in bones they are 0.7081490.708471 (±1s 0.0000160.000034). Conclusions: The Illyrian community on the island of Korcula relied primarily on agriculture for their food, consuming only cereals, vegetables, and meat from domesticated animals. They did not extensively use marine resources. They were in good health generally. The individuals examined were native residents of the island and can be associated through their dental morphology with the Western Eurasian population group. The average lifespan of the population corresponds to the typical life expectancy during the Late Iron Age.
The building integrated photovoltaic (BIPV) systems are a popular option for integrating renewable energy sources in the power system, and for users to reduce energy bills. This paper analyzes the performance of inverters in BIPV systems with oversized PV configurations. Oversizing PV systems has become a common practice to optimize energy production, particularly in periods of low sunlight, but it raises concerns about efficiency, power quality, and potential economic implications. Performance analysis is performed on two inverters, one operating under an overloaded regime due to the oversized PV installation and another under normal conditions. Several performance metrics are compared, including efficiency, thermal behavior, THD, and economic factors. The results demonstrate that although oversizing can slightly increase the inverter’s temperature and affect power quality, the efficiency was better for the overloaded inverter, although the investment costs have increased. These results offer practical insights for designing PV systems, showing that oversizing can be beneficial if properly managed.
Early detection of atrial fibrillation plays a crucial role in the timely prevention, diagnosis, and treatment of cardiovascular diseases. This paper proposes two different network architectures for automated atrial fibrillation detection. In the first architecture, a 1D CNN is used as a feature extractor and classifier. In the second hybrid architecture, a 1D CNN is used only as a feature extractor from ECG time series signals that supply a KNN with the most relevant features for further classification. Experimental results showed that the hybrid architecture achieved remarkable results and outperformed a 1D CNN.
Ultrasound images are used in various branches of medicine to detect diseases. The process of obtaining this data is complex due to procedures and legal restrictions, leading to scarce datasets. Different data augmentation techniques can be employed to improve classification performance. This paper shows that augmenting the ultrasound breast cancer images dataset using generative adversarial networks (GANs) increased the classification accuracy compared to the original dataset and compared to the dataset augmented using standard techniques.
Generative AI approaches such as ChatGPT are very popular and can be used for multiple purposes. This paper explores the possibility of using ChatGPT-4o for analysing visual information about 2D objects on provided images and returning annotated image results to the user. The achieved results indicate that ChatGPT can be used for the analysis of visual data and detect approximate values of desired parameters, however its generative capabilities are lacking and often unusable.
Smart wearable devices often contain heart rate monitoring capabilities. This paper presents an experimental study that compares the accuracy of smart watches (Xiaomi Amazfit Bip 3 and GEEKIN X10) to microcontroller-based systems that use raw sensors (HW-827 and MAX30102). The achieved results indicate that the accuracy of raw sensors is lower compared to smart watches and that the level of inaccuracy depends on the level of physical activity of the test subjects.
Modern IoT devices used for remote health monitoring use basic parameters such as heart rate, skin temperature and oxygen saturation. Maximum heart rate is an important parameter used for calculating heart rate zones that is helpful in diagnosis and prevention of cardiovascular diseases. This paper presents an information system that contains an IoT subsystem for heart rate measurement, and a web-server subsystem for monitoring by doctors that includes heart rate zone monitoring.
This paper presents a method based on Artificial Neural Networks (ANN) for magnetic flux density harmonics estimation in the vicinity of overhead lines. The proposed method can be employed for the magnetic flux density estimation in the cases of excitation currents with a pure sinusoidal waveform, as well as for excitation currents with harmonically distorted waveforms. The method utilizes two ANNs that are trained in a such way that enables their application for overhead lines of arbitrary phase conductor configurations and arbitrary current harmonic spectrum. In this paper, the proposed method is applied for magnetic flux density harmonics estimation in the vicinity of a typical distribution overhead line. The proposed method is validated by comparison with Biot-Savart based method. The obtained results demonstrate not only the accuracy and effectiveness of the proposed method but also the importance of considering the magnetic flux density harmonics in the vicinity of power facilities.
Random sequential adsorption (RSA) is a broadly used model for irreversible deposition on substrates. Over the last decades, a huge number of works have been published concerning this topic. Here we give a brief review of the results for irreversible deposition on two-dimensional discrete substrates. Depositing objects are randomly and sequentially adsorbed onto the substrate, and they are not allowed to overlap, so the jamming coverage θjam is less than in close packing. The kinetics of the process is described by the time-dependence of the coverage fraction θ(t), and for the discrete substrates, this dependence was found to be of the form: θ(t)=θjam−Ae−t/σ. Another topic of interest is the percolation of the deposit that can occur at a certain coverage. The coverage of the surface is increased through the RSA process up to the percolation threshold when a cluster that extends through the whole system appears. A percolating cluster arises in the system when the opposite edges are connected via some path of nearest neighbor sites occupied by the particles. Studying percolation is of great interest due to its relevance to conductivity in composite materials, flow through porous media, polymerization, the properties of nanomaterials, etc.
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