jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: V. V. Golovko
Source: arXiv (Cornell University) (preprint, 2024-10-25)
Field: Chemistry — Inorganic Chemistry

Estimation of Ru-97 Half-Life Using the Most Frequent Value Method and Bootstrapping Techniques A new and robust statistics was applied to previous measurements of the 97Ru half-life. This process incorporates the most frequent value (MFV) technique along with hybrid parametric bootstrap (HPB) method to deliver a more precise estimate of the 97Ru half-life. The derived value is T1/2,MFV(HPB) = 2.8385+0.0022-0.0075 days. This estimate corresponds to a 68.27% confidence interval ranging from 2.8310 to 2.8407 days, and a 95.45% confidence interval ranging from 2.8036 to 2.8485 days, calculated using the percentile method. This level of uncertainty is significantly lower-over 30 times-than the uncertainty in the previously recognized half-life value found in nuclear data sheets. Employing an alternate approach to minimization could further cut down the statistical uncertainty by 44% for the 97Ru half-life. In particular, the HPB method accounts for uncertainties in small datasets when determining the confidence interval. When the HPB method, in combination with the MFV approach, was used to review a four-element dataset of the specific activity of 39Ar based on underground data, the result was SA_MFV(HPB) = 0.966 +0.027 -0.020 Bq/kg_atmAr. This value results in a 68.27% confidence interval of 0.946 to 0.993, along with a 95.45% confidence interval of 0.921 to 1.029, also determined using the percentile method. Bootstrapping (finance) ; Value (mathematics) ; Estimation ; Statistics ; Econometrics ; Mathematics ; Computer science ; Economics ; Management Radioactive element chemistry and processing ; Nuclear reactor physics and engineering
Authors: Mustapha Zokay | Hicham Saylani
Source: Diagnostics (article, 2024-10-14)
Field: Chemistry — Analytical Chemistry

Blind Separation of Skin Chromophores from Multispectral Dermatological Images <b>Background/Objectives</b>: Based on Blind Source Separation and the use of multispectral imaging, the new approach we propose in this paper aims to improve the estimation of the concentrations of the main skin chromophores (melanin, oxyhemoglobin and deoxyhemoglobin), while considering shading as a fully-fledged source. <b>Methods</b>: In this paper, we demonstrate that the use of the Infra-Red spectral band, in addition to the traditional RGB spectral bands of dermatological images, allows us to model the image provided by each spectral band as a mixture of the concentrations of the three chromophores in addition to that of the shading, which are estimated through four steps using Blind Source Separation. <b>Results</b>: We studied the performance of our new method on a database of real multispectral dermatological images of melanoma by proposing a new quantitative performances measurement criterion based on mutual information. We then validated these performances on a database of multispectral dermatological images that we simulated using our own new protocol. <b>Conclusions</b>: All the results obtained demonstrated the effectiveness of our new approach for estimating the concentrations of the skin chromophores from a multispectral dermatological image, compared to traditional approaches that consist of using only the RGB image by neglecting shading. Multispectral image ; RGB color model ; Chromophore ; Artificial intelligence ; Computer science ; Computer vision ; Shading ; Pattern recognition (psychology) ; Dermatology ; Chemistry ; Medicine ; Computer graphics (images) ; Photochemistry Spectroscopy and Chemometric Analyses ; Color Science and Applications ; Industrial Vision Systems and Defect Detection
Authors: Serhiy Chuguyenko | Rami J. A. Hamad | Denys Kipnis | Maksym Minchenko
Source: Eastern-European Journal of Enterprise Technologies (article, 2024-06-28)
Field: Materials Science — General Materials Science

Determining the influence of compaction methods on the physical-mechanical properties of asphalt concrete samples The object of this study is the compaction methods of asphalt mixtures under laboratory conditions. The experience of determining the physical properties of coarse-grained asphalt concretes taken from the layers of the road pavement structure shows that their values do not correspond to those of the samples obtained by laboratory compaction using the pressing method. In 90 % of cases, the density of cores exceeds the density of laboratory samples while the indicators of void content and water saturation are significantly lower than for laboratory samples. The compressive strength indicators of asphalt concrete are almost independent of compaction methods and are not very informative. All of the above leads to the conclusion that the methods of laboratory compaction by pressing do not meet modern requirements. Low values of water saturation and void content of cores and laboratory samples compacted with a gyrator allow us to argue about outdated approaches to the design of grain compositions of asphalt concrete. Low-informative indicators of compressive strength indicate the need to use other mechanical characteristics that will make it possible to predict the properties of asphalt concrete in the pavement, for example, rutting resistance. As a summary, template solutions in the design of asphalt concrete warehouses and physical and mechanical characteristics are necessary only to establish compliance with the requirements of regulatory documents. The current work shows that it is almost impossible to predict the properties of asphalt concrete based on laboratory samples obtained by pressing. All this leads to the need to change the regulatory framework, which is possible by using regulatory documents of the countries in the European Union and the United States of America Compaction ; Asphalt ; Geotechnical engineering ; Materials science ; Asphalt concrete ; Composite material ; Geology Material Properties and Applications ; Material Properties and Failure Mechanisms ; Structural mechanics and materials
Authors: Cripps Anthony | G. Divyapratha | T. Geretharan
Source: Asian Journal of Agricultural Extension Economics & Sociology (article, 2024-11-05)
Field: Chemistry — Inorganic Chemistry

The Present and Future of the Coconut Cultivation towards the Export Industry: A Case on the Coconut Triangle in Sri Lanka In Sri Lanka, Coconut (Cocos nucifera L.) provides a livelihood for several million people from the production, processing, and marketing. It’s a major plantation product in the country. It is grown in all districts. The coconut triangle, which is distributed in the districts of Kurunegala, Puttalam, and Gampaha, accounts for about 55 per cent of the land used for coconut cultivation. The study was carried out to determine the status of coconut growers’ knowledge of new opportunities and trends in the export market within the coconut triangle. Primary data obtained from a sample survey in the coconut triangle. The study area was covered based on the extent of cultivation. The stratified random sampling method was used to select a sample of 100 coconut growers and data were collected through a structured pre-tested questionnaire. Data were analysed through the SPSS (Statistical Package for Social Sciences) software using descriptive statistics, correlation analysis and chi-squared test. Five-point Likert scaling was used to determine the coconut growers’ attitudes towards the status of the coconut export industry. The findings of the study revealed that more than half of the coconut growers in the study area (55%) cultivated coconut as their main primary occupation. The younger generation’s participation was very poor in coconut cultivation. Furthermore, highest percentage (81%) of the growers have moderate attitudes towards the exportation of coconut products. There was a positive and highly significant correlation observed between the coconut growers’ attitudes towards the existing coconut industry and attitudes towards the coconut export products at 0.01 level of probability and no significant association was found between the selected independent variables and the coconut growers’ attitudes towards the status of the coconut export products. Sri lanka ; Coconut oil ; Agricultural economics ; Business ; Commerce ; Economics ; Socioeconomics ; Biology ; Food science Coconut Research and Applications
Authors: Rebadj Chabane | Sabah Moussaoui | Mourad Belgasmia
Source: Technology audit and production reserves (article, 2024-02-24)
Field: Materials Science — Materials Chemistry

Double inclined cracks overlapping effect on mixed stress intensity factors using XFEM object-oriented implementation The object of research is the Mixed Mode Stress Intensity Factor (MMSIF) of a two-dimensional (2D) plate. With the emergence of modern technologies and advanced innovations which contribute to the development and improvement of the design, implementation and management of construction projects, it has become easier. However, it is very difficult to manufacture components free from unavoidable defects, such as cracks, which lead to material deterioration and ultimately shorten its service life. Based on the process of local enrichment region using partition of unity concept, the extended finite element method (XFEM) has overcome the limitations of the standard FEM method in terms of modeling and numerical simulation of discontinuities (cracks) while gaining its general advantages. This makes XFEM a powerful and widely used digital tool in recent years. One of the most frequently raised problems in the discontinuities field (cracks) is the phenomenon of juxtaposition of multiple cracks in a cracked isotropic plate, which must be studied to determine the extent of its effect on the crack stress intensity factor in order to obtain higher safety reliability. On this basis, an improved object-oriented programming (OOP) with extended finite elements was used because of its great importance and well-known benefits. In this paper, the MMSIF of a 2D plate is determined to show the effect of the out-of-phase orientation of the angle, as well as the effect of the juxtaposition of two inclined cracks. As a result of the research, it is shown that, the convergence between the results obtained in this study with those reported in the literature, and to theoretical values is remarkable, and their close agreement was noted. In the future, based on the object-oriented approach characteristics represented by flexibility, scalability, and modularity, which were explained in this research, this proposed approach can be enriched to include heterogeneous materials modeling, whether linear or nonlinear, crack propagation in dynamics, in addition to Complex 3D industrial problems. Classification of discontinuities ; Stress intensity factor ; Finite element method ; Extended finite element method ; Isotropy ; Structural engineering ; Stress field ; Computer science ; Convergence (economics) ; Engineering ; Mathematics ; Mathematical analysis ; Physics Material Properties and Failure Mechanisms ; Fatigue and fracture mechanics ; Engineering Diagnostics and Reliability
Authors: Pekka Korhonen | Madasamy Thangamuthu | Evandro Castaldelli | Ander Diego-López | Andreas Weilhard | Rob Clowes | James N. O’Shea | Andrea Laybourn | Anabel E. Lanterna
Source: ChemRxiv (preprint, 2024-09-24)
Field: Chemistry — Inorganic Chemistry

Selective Photocatalytic Reduction of CO2 to CH4 over NU-1000 Metal-Organic Frameworks CO2 adsorption and its subsequent utilization represent a promising avenue for mitigating climate change. The conver-sion of CO2 into valuable and useful products like carbon monoxide, methane, and methanol offers significant economic benefits. However, due to the low reactivity of CO2, the incorporation of CO2 adsorbents alongside catalytic materials has been pivotal in increasing the concentration of CO2 molecules around the catalytic sites. This strategy frequently relies on the precise deposition of the catalyst onto the adsorbent material. In this work, we explore NU-1000, a zirconium-based metal-organic framework originally designed as a CO2 adsorbent, to act as a selective photocatalyst for gas-phase CO2 reduction to CH4. NU-1000 contains UVA light-absorbing chromophore linkers, endowing it with the dual functionality of CO2 adsorbent and photocatalyst, which is crucial for efficient CO2 reutilization. Our research showcases an easily reproducible, and greener synthesis method for NU-1000 using micro-waves. We study the activity of NU-1000, including a functionalised variant, in the gas-phase photoreduction of CO2 to CH4 at room temperature and atmospheric pressure with electrons and protons derived from water. Remarkably, both the native and functionalised MOFs exhibit a rate of 170 and 800 μmol∙g-1∙h-1, respectively, alongside an exceptional selectivity of over 99%. These findings represent some of the highest reported values for gas phase CO2 photoreduction under atmospheric conditions. Our results provide a foundation for exploring materials that can serve as both catalysts and sorbents in the photocatalytic transformation of CO2 to value-added products. Photocatalysis ; Metal-organic framework ; Reduction (mathematics) ; Chemistry ; Catalysis ; Organic chemistry Metal-Organic Frameworks: Synthesis and Applications ; Advanced Photocatalysis Techniques ; Catalytic Processes in Materials Science
Authors: Boukaré OUEDRAOGO | Abdoul–Salam Ouédraogo | Moumouni Derra | Moumouni HEBIE | Kalifa Palm | Dieudonné Joseph Bahiebo
Source: Physical Science International Journal (article, 2024-12-02)
Field: Materials Science — Polymers and Plastics

Development and Preliminary Analysis of a Solar Dryer for Flour Dehydration Until now, drying flour in full sunlight has been the technique most widely used in Burkina Faso. This method exposes the flour to numerous risks of poisoning, pollution, soiling and destruction of nutritional qualities. Despite this, there are very few documented solutions to the problem. This has prompted this work on the design and preliminary study of a solar dryer for drying flour. To this end, the design approach based on unfavourable periods was used to dimension the solar collector elements. The initial studies were carried out experimentally, starting with a no-load study and then a load study. As a result of this work, a two-in-one solar dryer was designed and built. It was able to heat the drying air to 65°C in unfavourable weather conditions. During drying, the temperature reached 58°C in forced convection. However, the average drying temperature was below the predefined drying temperature range (45-55°C). The drying speed was less than half that predicted. As a result, the drying time was 10 hours 20 minutes instead of the planned 4 hours. The water content lost through the flour reached 31.14% on rack 1, whereas it was assumed to be 25%. Dehydration ; Solar dryer ; Environmental science ; Materials science ; Solar energy ; Chemistry ; Engineering Textile materials and evaluations
Authors: Oleksandr Kagitin | Roman Veselivskyi | Andrii Havrys | Yaroslav Ballo | Roman Yakovchuk | Богдан Ковалишин
Source: Eastern-European Journal of Enterprise Technologies (article, 2024-05-16)
Field: Materials Science — Materials Chemistry

Determining the influence of façade parameters and the width of a fire-proof eaves on preventing the spread of fire through external vertical structures of buildings The object of this study is the process of fire propagation through the surface of external wall structures with facade thermal insulation. The paper examines the influence of facade parameters and the width of a fire-proof eaves on preventing the spread of fire by external vertical structures using the example of a residential building. With the use of FDS modeling, the relationships between the parameters of external enclosing structures and the fire-proof eaves on the processes of limiting the spread of fire were investigated. The influence of the minimum parameters of the height of the inter-floor windowsill in the absence of a fire-proof eaves on the spread of fire was determined. The dependence of temperature change near the surface of the facade on the width of the fire-proof eaves and the height of the window between floors was established. Based on a series of simulated experiments, it was established that with a height of 1.0 m between floors and the absence of a fire-proof eaves, the critical temperature value is 250 °C. This value corresponds to the destruction temperature of a standard metal-plastic window structure. For the case when the wall height is 1.0 m, and the width of the fire-proof eaves is 0.75 m, the temperature value is 180 °C. That is, the safety condition of 250 °C is met. Based on the research, a dependence was found on the criterion of not exceeding the critical temperature of 250 °C at the level of 1.4 m of the facade of the building floor located above the fire floor. The criterion holds when the width of a fire-proof eaves is at least 0.4 m and the height of the window partition is 1.0 m, as well as when the width of the eaves is 0.5 m, and the height of the window partition is 0.6 m. It was established that the height of a window interfloor partition has a smaller effect than the width of the fire-proof eaves that separates the floors that are located above Eaves ; Structural engineering ; Environmental science ; Architectural engineering ; Facade ; Engineering Structural mechanics and materials ; Fire dynamics and safety research ; Construction Management and Sustainability
Authors: Sirsendu Jana | Abhik Ghosh
Source: arXiv (Cornell University) (preprint, 2024-09-24)
Field: Chemistry — Analytical Chemistry

Robust Inference for Non-Linear Regression Models with Applications in Enzyme Kinetics Despite linear regression being the most popular statistical modelling technique, in real-life we often need to deal with situations where the true relationship between the response and the covariates is nonlinear in parameters. In such cases one needs to adopt appropriate non-linear regression (NLR) analysis, having wider applications in biochemical and medical studies among many others. In this paper we propose a new improved robust estimation and testing methodologies for general NLR models based on the minimum density power divergence approach and apply our proposal to analyze the widely popular Michaelis-Menten (MM) model in enzyme kinetics. We establish the asymptotic properties of our proposed estimator and tests, along with their theoretical robustness characteristics through influence function analysis. For the particular MM model, we have further empirically justified the robustness and the efficiency of our proposed estimator and the testing procedure through extensive simulation studies and several interesting real data examples of enzyme-catalyzed (biochemical) reactions. Inference ; Linear regression ; Regression ; Enzyme kinetics ; Kinetics ; Mathematics ; Econometrics ; Robust regression ; Applied mathematics ; Computer science ; Statistics ; Enzyme ; Chemistry ; Artificial intelligence ; Physics ; Biochemistry Spectroscopy and Chemometric Analyses
Authors: Somashekharayya Hiremath
Source: Journal of Engineering and Applied Sciences Technology (article, 2024-10-31)
Field: Materials Science — Biomaterials

Microwave Ablation in Medical Device: Technology, Mechanism, Applications, and Challenges Microwave ablation (MWA) is a new and improved thermal ablation technology that uses electromagnetic waves to accurately target tissues. Conventional thermal ablation techniques, such as radiofrequency ablation (RFA), are less efficient and precise than MWA in treating tumors and other pathological conditions. Technology’s ability to generate higher temperatures without requiring grounding pads minimizes complications, while advancements in thermal control systems and real-time navigation platforms enhance procedural accuracy. In this paper, the mechanisms, applications, and effects of MWA are discussed while comparing it with the conventional methods and the increasing use of MWA in minimally invasive therapies. With its capacity to manage bigger tumors, lower rates of recurrence, and new clinical applications, MWA is changing the face of today's modern medical treatments. Microwave ; Mechanism (biology) ; Materials science ; Ablation ; Optoelectronics ; Microwave ablation ; Computer science ; Engineering ; Telecommunications ; Physics ; Aerospace engineering Electrospun Nanofibers in Biomedical Applications
Authors: Yu. A. Meish | M. A. Belova | Н. В. Майбородіна | Viacheslav Gerasymenko
Source: Eastern-European Journal of Enterprise Technologies (article, 2024-08-29)
Field: Materials Science — General Materials Science

Determining the effect of longitudinal stiffeners on the deformation of multilayer ellipsoidal shells under non-stationary loads The object of this study is the deformation of multilayer ellipsoidal shells under non-stationary distributed load. It is proposed to reinforce the shell with longitudinal stiffeners to enhance the strength of it. The application of Timoshenko's theory of shells and cores enabled the investigation of the influence of longitudinal stiffeners on the deformation of multilayer ellipsoidal shells under non-stationary loads with the discrete positioning of the stiffeners. A mathematical model of shell oscillations under various types of short-term non-stationary loads was based on the Hamilton-Ostrogradsky variational principle. The numerical algorithm based on the application of the integral-interpolation approach to the construction of finite difference schemes in spatial coordinates, combined with an explicit finite-difference scheme for the time coordinate, was used to solve the task set. It has been determined that reinforcing stiffeners significantly affect the deformed state of the multilayer ellipsoidal shell. The "shell-stiffeners" relation was taken into account as a base for research. The maximum deformation ε11 of the smooth three-layer ellipsoidal shell was on average 1.4 times greater than the deformation ε11 of the reinforced three-layer ellipsoidal shell throughout the entire studied time interval. It was determined that over time the presence of reinforcing stiffeners has a more significant impact on the deformed state of the reinforced ellipsoidal shell. A distinctive feature of this research is the consideration of the discrete placement of reinforcing stiffeners which made it possible to investigate the impact of longitudinal stiffeners on the deformation of multilayer ellipsoidal shells under non-stationary loads. The results could be used for the investigation of applied problems in research organizations and design bureaus when designing shell structures Ellipsoid ; Deformation (meteorology) ; Materials science ; Composite material ; Structural engineering ; Engineering ; Geology ; Geodesy Material Properties and Applications ; Advanced Theoretical and Applied Studies in Material Sciences and Geometry ; Structural mechanics and materials