Typical Values Research Articles

Zircon within chromitite requires revision of the tectonic history of the Eoarchean Itsaq Gneiss complex, Greenland

The Ujaragssuit Nunât layered (UNL) unit in the Itsaq Gneiss Complex, west Greenland, has been considered to contain one of the oldest chromitites on Earth based on ∼ ca. 4.1 Ga Hadean whole rock Pt–Os model ages and ca. 3.81 Ga zircon U-Pb age of the surrounding orthogneiss. This study obtained zircon from the chromitite within this unit as well as granitoid sheets that intruded into the UNL unit. In–situ U–Pb–Hf–O isotope measurements were made on the zircons. Zircons from both the chromitite and the intrusive granitoids show concordant U–Pb ages of ca. 2.97–2.95 Ga. In contrast, Hf and O isotopic analyses indicate that zircons in the chromitites have a different origin from those in the intrusive granitoids. Zircons from granitoids yielded Th/U ratios higher than 0.2, initial Hf isotope ratios of 0.2805 – 0.2807 (i.e., initial εHf value of − 11 to − 5), and δ18O values of mostly 6.0‰–7.0‰, which are typical for felsic igneous rocks in Archean continental crust. The least altered zircons from a chromitite exhibited initial Hf isotope ratios of 0.28078 – 0.28084 (i.e., initial εHf value of − 1.1 to − 0.4), close the chondritic value at ca. 3.0 Ga and the depleted mantle at ca. 3.2 Ga. These zircons also have δ18O values of 4.2‰–6.1‰ which correspond to typical mantle values. The other chromitite zircons yielded Th/U ratios lower than 0.1, and Hf and O isotopic compositions ranging between the least altered zircons and the intrusive granitoid zircons. These results indicate that the zircons in the chromitites crystallized before or during the 2.97–2.95 Ga granitoid intrusion and most of the zircons were altered by subsequent metasomatism. Furthermore, the present results suggest that zircons in the chromitites originally had depleted Hf isotopic compositions at ca. 3.2–3.0 Ga. This can be explained by two different models of the evolution of the UNL unit. One is that if the UNL unit was formed at > 3.81 Ga as previously thought, with the zircons in the chromitites subsequently being precipitated by ca. 3.2–2.95 Ga during metamorphism or metasomatism. The other model is that the UNL unit itself was actually formed at ca. 3.2–3.0 Ga, with zircon in the chromitite representing the crystallisation age of the unit, which was then tectonically incorporated into the ca. 3.81 Ga orthogneiss prior to the 2.97–2.95 Ga granitoid intrusion event. In either case, our zircon analyses reveal significant evolutionary history prior to depleted mantle Hf model ages of 3.2–2.95 Ga. Revision of the geotectonic evolution of the UNL unit and the Itsaq Gneiss Complex is therefore required.

KL-6 levels in the connective tissue disease population: typical values and potential confounders-a retrospective, real-world study.

Krebs von den Lungen 6 (KL-6) is a potential biomarker for determining the severity of interstitial lung disease (ILD) in patients with connective tissue disease (CTD). Whether KL-6 levels can be affected by potential confounders such as underlying CTD patterns, patient-associated demographics, and comorbidities needs further investigation. From the database created by Xiangya Hospital, 524 patients with CTD, with or without ILD, were recruited for this retrospective analysis. Recorded data included demographic information, comorbidities, inflammatory biomarkers, autoimmune antibodies, and the KL-6 level at admission. Results of CT and pulmonary function tests were collected one week before or after KL-6 measurements. The percent of predicted diffusing capacity of the lung for carbon monoxide (DLCO%) and computed tomography (CT) scans were used to determine the severity of ILD. Univariate linear regression analysis showed that BMI, lung cancer, TB, lung infections, underlying CTD type, white blood cell (WBC) counts, neutrophil (Neu) counts, and hemoglobin (Hb) were related to KL-6 levels. Multiple linear regression confirmed that Hb and lung infections could affect KL-6 levels independently; the β were 9.64 and 315.93, and the P values were 0.015 and 0.039, respectively. CTD-ILD patients had higher levels of KL-6 (864.9 vs 463.9, P < 0.001) than those without ILD. KL-6 levels were closely correlated to the severity of ILD assessed both by CT and DLCO%. Additionally, we found that KL-6 level was an independent predictive factor for the presence of ILD and further constructed a decision tree model to rapidly determine the risk of developing ILD among CTD patients. KL-6 is a potential biomarker for gauging the incidence and severity of ILD in CTD patients. To use this typical value of KL-6, however, doctors should take Hb and the presence of lung infections into account.

Immobilization on biomimetic silica nanoparticles as a highly effective strategy for the stabilization of Issatchenkia orientalis β-glucosidase in wine conditions

β-Glucosidases (BGLs) are key enzymes for the hydrolysis of glycosidic aroma precursors of wines. However, BGLs produced by oenological yeasts are often inactive or unstable at typical wine pH values. In this work, different immobilization strategies on biomimetic NPs were tested to enhance the stability of Issatchenkia orientalis BGL and compared with traditional methods on agarose and Eupergit. Immobilization to biomimetic silica NPs by ionic interactions proved to be the most efficient method to achieve enzyme stabilization in model wine at pH 4.0. In particular, the subsequent glutaraldehyde crosslinking, achieved a high immobilization efficiency (71%) with an outstanding stabilization factor of 240-fold with respect to the soluble enzyme. This enzyme derivative preserved practically all the activity (98%) after15 days in model wine supplemented with Muscat glycosides, making possible its application for the release of aroma compounds relevant to the typicity of wine.

The complex shape of the outer edge of Saturn’s B ring, as observed in Cassini occultation data

We determine the time-variable shape of the outer edge of Saturn’s B ring using the complete set of Cassini radio and stellar occultation data obtained between mid-2005 and the End-of-Mission in late 2017, considerably expanding the range and number of individual ring edge measurements used in previous analyses (Spitale and Porco, 2010; Nicholson et al., 2014a). During this 12-year interval, the dominant m=2 pattern driven by the Mimas 2:1 inner Lindblad resonance completed just over two rotations relative to Mimas, with a circulation period of 5.362 yr, while its radial amplitude varied from a minimum of 4 km to a maximum of 71 km. This circulation pattern has remained essentially unchanged over the full period of the observations. We confirm the existence of four additional perturbations with azimuthal wavenumbers m=1, 3, 4 and 5 and mean amplitudes ranging from 5 to 24 km, which we interpret as normal or edge modes, possibly triggered by viscous overstabilities in the dense B ring (Borderies et al., 1985; Longaretti, 2018). Fits of a simple WKB model to the observed pattern speeds of the edge modes with m≠1 suggest an average surface mass density in the outer 30 km of the B ring of ∼100 g cm−2, somewhat greater than the 50–70 g cm−2 inferred from density and bending waves in most other regions of this ring (Hedman and Nicholson, 2016). The m=1 mode, which extends further into the B ring, yields a more typical value of 60 g cm−2. Surprisingly, all four of these modes exhibit significant librations in their amplitudes and phases, with periods between 2.3 and 8.6 yr and amplitudes of 1.6 to 7.4 km. The origin of these librations is unknown and it is unclear if they are truly periodic and will maintain their amplitudes, periods, and phases over timescales of centuries. Their frequencies do not match those expected for interference between edge modes with varying numbers of radial nodes. Instead, they may represent periodic oscillations in the amplitudes of individual normal modes or nonlinear, non-resonant coupling between normal modes with different values of m, leading to long-term quasi-periodic variations in the mode amplitudes.

Exploratory Training: When Annonators Learn About Data

Data systems often present examples and solicit labels from users to learn a target model, i.e., active learning. However, due to the complexity of the underlying data, users may not initially have a perfect understanding of the effective model and do not know the accurate labeling. For example, a user who is training a model for detecting noisy or abnormal values may not perfectly know the properties of typical and clean values in the data. Users may improve their knowledge about the data and target model as they observe examples during training. As users gradually learn about the data and model, they may revise their labeling strategies. Current systems assume that users always provide correct labeling with potentially a fixed and small chance of annotation mistakes. Nonetheless, if the trainer revises its belief during training, such mistakes become significant and non-stationarity. Hence, current systems consume incorrect labels and may learn inaccurate models. In this paper, we build theoretical underpinnings and design algorithms to develop systems that collaborate with users to learn the target model accurately and efficiently. At the core of our proposal, a game-theoretic framework models the joint learning of user and system to reach a desirable eventual stable state, where both user and system share the same belief about the target model. We extensively evaluate our system using user studies over various real-world datasets and show that our algorithms lead to accurate results with a smaller number of interactions compared to existing methods.

Scintillation properties of Pr-doped CaWO4 single crystals synthesized by the floating zone method

Pr-doped CaWO4 single crystals with dopant concentrations of 0.05–1% were synthesized by the floating zone method, and the photoluminescence and scintillation properties were evaluated. Emissions due to the 4f–4f transitions of Pr3+ were observed in visible–near-infrared ranges under visible light and X-ray irradiation. The X-ray-induced scintillation decay times were typical values of the transitions of Pr3+ when monitored at 380–900 nm. The afterglow levels when 20 ms passed after X-ray irradiation were calculated to be 573–730 ppm and increased as the dopant concentrations increased. In the integration-type scintillation detector property, 0.05, 0.1, and 0.5% Pr-doped samples showed good linearity between X-ray exposure dose rate and scintillation signals from 0.05 to 5 Gy/h.

Total-aware suppressed possibilistic c-means clustering

Cutset-type possibilistic c-means (CPCM) is an improved version of possibilistic c-means (PCM), and it addresses the issue of consistency clustering in PCM. However, the clustering performance has not significantly improved, and its convergence speed is still slow. Hence, a total-aware suppressed possibilistic c-means (TSPCM) clustering is proposed in this paper. Firstly, from a global perspective, the typicality values of all the non-winners of samples inside the cluster core are decreased by the suppressed factor while increasing the typicality values of all the winners of samples in the same core. Meanwhile, the typicality values of samples outside the cluster core remain unchanged. The corrected typicality values are used to update the clustering centers, and the modified clustering centers are again used to renew the typicality values alternately until the algorithm converges. Secondly, the objective function of the proposed TSPCM is constructed, and Zangwill's theorem firmly establishes its convergence. Finally, two robust total-aware suppressed algorithms are presented when TSPCM is used for the clustering of numerical data with noise and the segmentation of noisy images. Experimental results show that the proposed TSPCM and its robust algorithms are obviously superior to existing state-of-the-art PCM-related algorithms.

A VALUE CHAIN ANALYSIS OF AGROFORESTRY PRODUCTS IN THE SOUTH-WESTERN REGION OF BANGLADESH

This study explores the market linkages in a typical agroforestry value chain in Bangladesh, particularly the participation of the micro and subsistence level farming and household-community units in this chain. The study area is Dumuria Upazila which is a 30 square km land area in the outskirt of Khulna which is the third largest city of Bangladesh located in the south-western region of Bangladesh. Agro-products produced in the Dumuria Upazila and then sold in the areas including Dumuria Bazar and Gollamari Bazar which are peri-urban locations of Khulna city. The particular objectives of this study were to identify different value chains of agroforestry products, the relationship of various intermediaries within it, and to explore the impact of agroforestry practices on the socioeconomic condition of the local population. The assessment was performed by using multistage sampling of 80 households using a semi-structured questionnaire, and 30 intermediaries were included on convenience basis for tracing the structure of market linkage and existing problems, in the marketing of agro-products in the study area. Explored network structures of the value chain have revealed that both the marketing of agroforestry crops and timber, include the intermediaries that have contributed to different forms of value-addition to the original product and produced higher gains for the participants in the value chain. Value chain participants in the point of origin of the products, farmers and households, reported being discriminated in terms of price taking while end-market intermediaries were found to absorb major shares of the total gain originated in the value chain. The farmers were neutral in terms of satisfaction in case of purchase by the government, while the intermediaries were dissatisfied with the same. Findings of this study contributes in generating understanding the process of value creation, power structure, and gain sharing in the localized natural resources-based value chains.

Bridging the Great Divide: Investigating the Potent Synergy between Leadership, Zhong-Yong Philosophy, and Green Innovation in China

Zhong-yong thinking, a typical value orientation and mode of thought in traditional Chinese culture, has garnered significant scholarly attention. Various cross-sectional studies have explored the relationship between Zhong-yong thinking and innovation; yet, research specifically examining the impact of Zhong-yong thinking on green innovation is scarce. This study adopts the upper echelons theory and theory of manager cognition to investigate the influence of entrepreneurs’ Zhong-yong thinking on green innovation while simultaneously considering institutional pressure and enterprise ownership types as boundary conditions. By analyzing 302 questionnaire responses, the empirical results demonstrate a direct positive effect of Zhong-yong thinking on green innovation. Moreover, institutional pressure positively moderates the relationship between Zhong-yong thinking and green innovation. State-owned enterprises exhibit a more significant impact of Zhong-yong thinking on green innovation than non-SOEs. Overall, this study contributes to the theoretical research of Zhong-yong in management disciplines, particularly in the green innovation literature. Its findings also hold implications for the practice of green innovation in enterprises.

Multimodal Presentation of Interactive Audio-Tactile Graphics Supporting the Perception of Visual Information by Blind People

Due to the limitations in the perception of graphical information by blind people and the need to substitute the sense of sight with other senses, the correct use of multimedia in the presentation of graphics is particularly important. The aim of the authors was to correctly present visual information in the tactile and audio form and to provide contextually selected information to reduce the existing cognitive barriers. In this article, the authors decided to research the method of exploring a tactile picture by a blind person and providing contextual and semantic information about the touched image elements using the developed tool for multimodal presentation of interactive audio-tactile graphics supporting the perception of blind people. The use of multimedia should improve the perception of the conveyed content. Therefore, the effectiveness of interpreting the information contained in the tactile image is verified by analyzing the tactile, audio, and contextual perceptions during the experiments. The following issues were considered in detail from the point of view of the blind and visually impaired: the recognition of shapes of image elements depending on their size and properties, the optimal width of elements displayed on the tablet screen, the time intervals between taps on an image element, and the acceptable length of graphic element audio description. The results from this study suggest the need to select the image presentation parameters in various perception channels to the user's needs. The findings of our research on tactile shape perception of geometric figures indicate potential problems in recognizing the shapes of figures in the case of wrong preparation of tactile pictures. In the case of a small difference in the proportions of the length of the sides of the figure or a slight difference in the measures of the angles of the figure sides, we have noticed that most blind people fail to recognize its shape. Considerable progress in improving such perception can be achieved by increasing the proportions in the lengths of the sides and the measures of the angles between the sides of the figure. Further steps concern introducing an alternative audio description of the properties of the figure so as to improve the interpretability of the figure shape. For most users, the width of a virtual line in a digital image displayed on a tablet should be around 5 mm for a corresponding 1 mm tactile line. The configuration of the time intervals defining the user's gestures (two-taps, three-taps) should be about 340 ms. Applying audio descriptions to tactile picture elements improves the understanding and interpretation of the information presented on it. Most participants in the test group accepted 5 to 10 seconds of voice prompts. Longer messages were incomprehensible, and details were hard to remember. In the proposed solution, the audio description can be divided into two or three different descriptions available to the user after tapping two or three times on an image element. It allows the user to decide on the amount of contextual information needed about the touched tactile picture element. The research attempted to show the typical values of various image presentation parameters and their ranges of values and indicated effective methods of their selection for a specific system user.

Dynamic response of common stone masonry buildings under uncertain material properties

The major causes of the failure of the structure are either improper design or improper construction. Therefore, accurate analysis for the design of the structure is of utmost importance. However, it is extremely difficult and impractical to determine all the engineering properties of the building structure and all of its components’ analysis of each building. It is customary to adopt typical values of material properties for the analysis of such structures, usually required for seismic vulnerability analysis. However, there is a high variation in material characteristics, especially of stone masonry that can have a significant effect on the analysis. Typical stone masonry was investigated at the site and then analyzed using finite element model (FEM). Parametric analysis was conducted for a range of young’s modulus of elasticity values of a masonry wall. The dynamic characteristics of the building were determined from the modal analysis. Seismic loading was done using dynamic methods and its effect was determined as design stresses and building deformations for the comparison. The results indicated that various building responses have a different relationship with the elasticity parameter of the wall, indicating that a very good engineering judgment is required in the analysis of stone masonry buildings that do not have standard material properties.

Gas and stellar kinematic misalignment in MaNGA galaxies: What is the origin of counter-rotating gas?

Context. Kinematic misalignment between gas and stellar components is observed in a certain fraction of galaxies. It believed to be caused by the acquisition of gas from the external reservoir by, for example, major or minor mergers, accretion from cosmological filaments, or the circumgalactic medium. Aims. We aim to constrain the possible sources of the gas that forms the counter-rotating component. Methods. We derived the gas-phase oxygen abundances of 69 galaxies with a kinematic misalignment between gas and stellar components from the MaNGA DR17 survey and compared them with the metallicity expected according to the mass–metallicity relation. Results. We find that the oxygen abundance of the counter-rotating gas in our sample is higher than 8.2 dex, which rules out a significant role for the inflow of pristine gas. Meanwhile, there is a significant difference in the oxygen abundance of the counter-rotating gas between red and blue galaxies. In general, the oxygen abundance is lower than expected for the stellar mass in red galaxies but is compatible with or even higher than typical values for the stellar mass in blue galaxies. Conclusions. We show that the exchange of enriched gas between galaxies is the most plausible mechanism for explaining the metallicity of counter-rotating gas components in galaxies of all masses and colors. Meanwhile, minor mergers may play a significant role in the formation of counter-rotating gas components in red and quenched galaxies.

Efektivitas Penggunaan Media Sosial Tiktok terhadap Hasil Belajar Siswa di SDN 36 Lubuk Pasing Pesisir Selatan

This study aims to see whether the use of social media TikTok is effective in increasing the learning outcomes of class VI students in subject matter of Islamic Religious Education at the Public Elementary School of 36 Lubuk Pasing, Bayang, Pesisir Selatan. Quantitative research and experimental methods are used in this study. Pre-test and post-test, as well as observation with a sample of 18 students, were used as data collection methods. After that, students were divided into two groups, with half of each group representing the experimental group and the other half representing the control group. Analytic prerequisite tests, such as normality tests and homogeneity tests, are used in data analysis techniques. The T-test or paired sample T-test is then used to test the hypothesis. The results of the research in the experimental group and the control group for the 2022/2023 academic year show that the experimental group obtained the highest score from the research analysis. This is evidenced in the 85–90 range, where there were 4 students, or 44.4%, with an average post-test of 80.56, while the control group got an average of 48.89. The consequences of the examination in the trial group after being given the treatment and the post-test were carried out to get a typical value of 80.56, which is classified as very high. A Sig (2-tailed) value of 0.05 was obtained after calculating the hypothesis test with the help of SPSS version 22 and paired sample t-tests. Therefore, it can be concluded that student learning outcomes increase and are different when using TikTok compared to students who don't. Therefore, the more various media used for learning Islamic religious education, the more likely it is to improve student learning outcomes, and students are increasingly motivated to study in order to achieve high learning outcomes.

Investigating CT head diagnostic reference levels based on indication-based protocols – a single site study

IntroductionThis study aimed to provide clinically-relevant insights into establishing CT DRLs based on indication-based protocols in Ireland, focusing on CT head examinations performed at a neurology centre of excellence hospital. MethodsDose data were collected retrospectively. Typical values for six CT head indication-based protocols were established using a sample size of 50 patients for each protocol. Typical values for each protocol were set as the median of the distribution curve. Dose distributions for each protocol were calculated and compared using non-parametric median test (k-samples) to ascertain significant dose differences between the typical values. ResultsMost typical values pairings showed significant differences (p < 0.001) except between stroke/non-vascular brain, stroke/acute brain, and acute brain/non-vascular brain pairings. This was expected due to similar scan parameters. The typical value for stroke (3-phases angiogram) was 52% lower than the typical value for stroke. Dose levels of the male populations recorded were higher than female populations for all protocols. Statistical comparison showed significant differences for dose quantities and/or scan length between both genders in five protocols. ConclusionProposed values for DLP were up to 63% and 69% lower than the EU and Irish national DRLs respectively. Establishment of CT stroke DRLs should be based on the scan performed instead of number of scan acquisitions. Lastly, gender-based CT DRLs for specific protocols within the head region require further investigation. Implications for practiceWith increasing CT examinations worldwide, radiation dose optimisation is key. The value of indication based DRLs is to enhance the required patient protection so image quality can be maintained, however with relevant DRLs for varying protocols. Establishment of CT typical values and site specific DRLs for procedures beyond the national DRLs can drive dose optimisation locally.

Novel holistic pharmacokinetic model applied to plasma and urine concentrations of 2,5-dihydroxybenzene sulphonate following administrations of calcium dobesilate and etamsylate to exercised horses.

Calcium dobesilate (CD) is a synthetic venoactive drug used in veterinary medicine to treat equine navicular disease. Etamsylate is a haemostatic agent used in horses for the treatment of exercise-induced pulmonary haemorrhage. Both etamsylate and CD dissociate in the circulatory system with 2,5-HBSA as the active drug. The aim of the research was to be able to provide detection time (DT) advice from pharmacokinetic (PK) studies in Thoroughbred horses to better inform trainers, and their veterinary surgeons, prescribing these substances for treatment of Thoroughbred racehorses. Two (pilot study) and six (final study) horses were given 28 and 9 repeated dose of CD (3 mg/kg BID) respectively. Two horses were each given a single intravenous (IV) dose of etamsylate (10 mg/kg). Plasma and urine 2,5-HBSA concentrations were measured by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The CD pilot study revealed that steady state could be reached with a few days and that 2,5-HBSA in plasma and urine shows instability during storage at -20°C but appears stable at -80°C. A novel holistic non-linear mixed-effects three-compartmental PK model was developed that described both plasma and urine concentrations of 2,5-HBSA, from either CD or etamsylate administration. Typical values for 2,5-HBSA clearance and bioavailability were 2.0 mL/min/kg and 28% respectively. Using the parameters obtained from this PK model, in conjunction with methodology developed by Toutain, afforded a possible screening limit (SL) that can regulate for a DT of 3 days in urine; however, a corresponding SL in plasma would be below current levels of detection. However, it is the responsibility of the individual racing authorities to apply their own risk management with regard to SLs and DTs.

Review on integrated green hydrogen polygeneration system——Electrolysers, modelling, 4 E analysis and optimization

Green hydrogen production by water electrolysis is sustainable and carbon-free for energy storage. This paper introduces recent development in integrated green hydrogen polygeneration. Throughout this review, theoretical concepts, design types, and recent developments related to the integration of Alkaline Electrolysis (AE), Proton Exchange Membrane Electrolysis (PEME), and the Solid Oxide Electrolysis Cell (SOEC) are summarised. This review evaluates the thermodynamic efficiency and economic impact of green hydrogen production integrated with different energy sources, energy storage and power cycles. Compared with two kinds of commercially applied methods (AE and PEME), SOEC is the state-of-the-art method to produce hydrogen, which can be integrated with external heat to reduce energy consumption. SOEC avoids the inevitable energy loss in AE and PEME, which leads to low-temperature waste heat evaluated as exergy destruction rather than utilized. The overall efficiency improvement of SOEC systems is over 10%. In most cases, the efficiency is always over 70%, and over 80% in some cases, which exceeds the typical values of 20%–60% from AE and PEME systems. The produced hydrogen can be stored and transported, as well as being used as a feedstock for chemical production, forming a polygeneration system with multiple energy sources, desalination, and fuel production. The latest lifetime of SOEC was predicted at 50,000 h or more, which is the minimum requirement to be commercially competitive. In the literature review, 80.4% of papers chose exergy efficiency as assessment index, compared with 67.9% of energy efficiency. And 58.9% of them chose genetic algorithm to complete multi-objective optimization.

Optimizing multi-interlayered additive manufacturing for high strength robust joints in Inconel 718 and Ti–6Al–4V alloys

The fabrication of a robust joint of Ti–6Al–4V and Inconel 718 is indispensable for numerous industries including aerospace, space, and biomedical industries, and to date not achieved without intermetallic compounds (IMCs) and microcracks. In this study, the additive manufacturing of a dissimilar functionally graded joint of Ti–6Al–4V and Inconel 718 alloy was achieved by employing V, Cr, and Ni multi-interlayers. Interlayer materials were carefully selected to mitigate the limitations of brittle IMC formation. Microstructure characterization, EBSD, and elemental analysis confirmed that all joints of Ti–6Al–4V/V, V/Cr, Cr/Ni, and Ni/Inconel 718 were crack and IMC-free, despite substantial elemental diffusion throughout the fabrication route. The as-built specimen exhibited a tensile strength of 210 MPa, which increased to 250 MPa after stress-relief heat treatment and is 40% higher than the reported tensile strength of 150 MPa for a laser welded Ti–6Al–4V/Inconel 718 specimen. The maximum hardness of the entire fabrication was 380 VHN, a typical solid-solution hardness value, indicating no detrimental brittle IMC formation. Furthermore, the finite elemental analysis predicted a moderate stress level of 90 MPa at the interface, indicating robust fabrication.

Experimental Efficiency of Single Pass Solar Air Heater

The solar heat collector with the impingement of jet lower plate (SAHJF) experimentally designed and operated with typical parameters obtained from theoretical analysis to contained the maximum efficiency of the performance of thermal transfer. Then it was developed by replacing the flat absorber by the corrugated absorber (SAHJC) to enhance the efficiency. The flow rate of mass was selected equal and more than the typical value and the intensities of the solar radiation were chosen equal and less than the typical value to investigate the effect of both on the thermal transfer efficiency for SAHJF and SAHJC. Since the system works with a short range of temperature, the temperatures recorded were sensitive and needed a large accuracy. Therefore, an analysis method was proposed and applied to the data to be sure that it reflects the variance of temperature with different operating parameters. The correlation of temperature difference between the outlet and the inlet air with different flow rate and different intensities of irradiation for SAHJF and SAHJC was presented and compared.

Development and Evaluation of a Multifrequency Ultrafast Doppler Spectral Analysis (MFUDSA) Algorithm for Wall Shear Stress Measurement: A Simulation and In Vitro Study.

Cardiovascular pathology is the leading cause of death and disability in the Western world, and current diagnostic testing usually evaluates the anatomy of the vessel to determine if the vessel contains blockages and plaques. However, there is a growing school of thought that other measures, such as wall shear stress, provide more useful information for earlier diagnosis and prediction of atherosclerotic related disease compared to pulsed-wave Doppler ultrasound, magnetic resonance angiography, or computed tomography angiography. A novel algorithm for quantifying wall shear stress (WSS) in atherosclerotic plaque using diagnostic ultrasound imaging, called Multifrequency ultrafast Doppler spectral analysis (MFUDSA), is presented. The development of this algorithm is presented, in addition to its optimisation using simulation studies and in-vitro experiments with flow phantoms approximating the early stages of cardiovascular disease. The presented algorithm is compared with commonly used WSS assessment methods, such as standard PW Doppler, Ultrafast Doppler, and Parabolic Doppler, as well as plane-wave Doppler. Compared to an equivalent processing architecture with one-dimensional Fourier analysis, the MFUDSA algorithm provided an increase in signal-to-noise ratio (SNR) by a factor of 4-8 and an increase in velocity resolution by a factor of 1.10-1.35. The results indicated that MFUDSA outperformed the others, with significant differences detected between the typical WSS values of moderate disease progression (p = 0.003) and severe disease progression (p = 0.001). The algorithm demonstrated an improved performance for the assessment of WSS and has potential to provide an earlier diagnosis of cardiovascular disease than current techniques allow.

Enhancing the Fatigue Strength of the Weld Line in Advanced Polymer Injection Molding: Gas-Assisted Mold Temperature Control for Thermoplastic Polyurethane (TPU) Composites.

This study presents an innovative approach to enhancing weld line strength in advanced polymer injection molding through applying gas-assisted mold temperature control, significantly increasing mold temperature beyond typical values observed in conventional processes. We investigate the effects of various heating times and frequencies on the fatigue strength of Polypropylene (PP) samples and the tensile strength of Acrylonitrile Butadiene Styrene (ABS) composite samples at different Thermoplastic Polyurethane (TPU) percentages and heating times. Using gas-assisted mold heating, mold temperatures exceeding 210 °C are achieved, which represents a significant advancement compared to the standard mold temperatures of less than 100 °C. As a result, the fatigue strength of the PP sample with mold heating at 15 s shows a remarkable increase of up to 5.4 times at 5 Hz compared to the sample without mold temperature control. Moreover, ABS/TPU blends with 15 wt.% TPU exhibit the highest ultimate tensile strength (UTS) value of 36.8 MPa, while blends with 30 wt.% TPU have the lowest UTS value of 21.3 MPa. This advancement demonstrates the potential for improved welding line bonding and fatigue strength in manufacturing. Our findings reveal that increasing the mold temperature before injection results in higher fatigue strength in the weld line, with the TPU percentage having a more significant influence on the mechanical properties of ABS/TPU blends than heating time. The results of this study contribute to a deeper understanding of advanced polymer injection molding and offer valuable insights for process optimization.