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Evaluation of morpho-cellular and spectroscopic characteristics of Myristica fragrans Houtt mace across three different maturation stages (juvenile, raw and ripe)
This study was based on comprehensive analysis of Myristica fragrans Houtt mace samples across various stages of maturation (juvenile, raw and ripe). The anatomical analysis was performed using SEM coupled EDX spectroscopy that revealed distinct cellular changes and the presence of oil-storage structures in the mace. The EDX analysis further confirmed the presence of key elements such as carbon (C), oxygen (O) and potassium (K) which contribute to mace's pharmacological properties. Spectrophotometric analysis revealed a steady increase in chlorophyll content as the mace matures, with total chlorophyll content rising from 1.02 during the juvenile stage to 1.25 at the raw stage and reaching 3.29 at the ripe stage. The Plant Senescence Reflectance Index (PSRI) shows a rise in carotenoid content, increasing from 0.15 in the juvenile stage to 0.17 at the raw stage and reaching 0.82 at the ripe stage. This increase correlates with the mace's colour transformation to crimson red during ripening. The FTIR spectroscopy analysis provided a detailed chemical characterization of the mace, identified various functional groups (carboxylic acid, aldehyde, alkanes, azides) and organic molecules. The presence of multiple functional groups across the maturation stages suggested a complex composition that likely contributes to the mace's sensory and pharmacological qualities. 2024 World Researchers Associations. All rights reserved. -
Performance evaluation and sustainability analysis of geopolymer concrete developed with ground granulated blast furnace slag and sugarcane bagasse ash
This experimental work aims to determine the workability, strength and sustainability aspects of geopolymer concrete developed with GGBS and SCBA in five different proportions of 100-0%, 95 ? 5%, 90 ? 10%, 85 ? 15%and 80 ? 20%. 8M NaOH concentration and Na2SiO3 solutions are used as an alkaline activator in mixes developed. Na2SiO3 to NaOH ratio of 2.5 and 0.5 alkaline liquid to binder ratio is employed in this study to develop ambient cured geopolymer concrete. The results show that the standard consistency and FST of geopolymer paste increases with an increase in the SCBA content of mixes developed. Cs, Sts and Fs decreased with an increase in the content of SCBA in geopolymer concrete mixes. The 28 days Cs of geopolymer concrete developed under ambient cured condition varied from 63.56 to 39.59MPa. Regression analysis was performed to find the correlation between Sts and Fs to Cs. This study aims to outline a unique technique of utilizing an agro industrial waste by product i.e., sugarcane bagasse ash which in turn reduces disposal problem to some extent. According to the test findings, Sugarcane bagasse ash up to 20% can be used as precursor to develop sustainable geopolymer concrete. Due to the high cost of chemicals and river sand the cost of geopolymer concrete developed is slightly higher than normal concrete. Also, as the percentage of SCBA increase in the geopolymer concrete the demand for energy is reduced. Additionally, incorporation of sugarcane bagasse ash will also reduce disposal problems and reduces CO2 emissions into the atmosphere. The Author(s), under exclusive licence to Springer Nature Switzerland AG 2024. -
Modified Montmorillonite Catalysed Ultrasonic Assisted one-pot Synthesis of Novel 2,3-dihydroisoxazolo[5,4-d] pyrimidin-4(7H)-ones as Potential Anticancer Agents
The development of novel compounds with potential anticancer activity is imperative for combating the challenges posed by cancer. In this study, a modified montmorillonite based catalyst is employed for the synthesis of 2,3-dihydroisoxazolo[5,4-d] pyrimidin-4(7H)-ones, which are promising candidates for anticancer agents. Montmorillonite is modified using mixed metal oxides, typically Al2O3 and CeO2, by a facile approach followed by standard spectroscopic and electron microscopic characterizations. It is then employed for the one-pot synthesis of a series of 2,3-dihydroisoxazolo[5,4-d] pyrimidin-4(7H)-ones. The synthesis protocol, mediated by ultrasound, is simple, efficient, and environment friendly. The mixed metal oxide pillared montmorillonite catalyst exhibits high catalytic activity and selectivity, facilitating the formation of the desired compounds in good to excellent yields. The synthesized compounds are characterized using various spectroscopic techniques such as 1H NMR, 13C NMR and mass spectrometry. Furthermore, the anticancer activity of the synthesized compounds is evaluated against a series of cancer cell lines, revealing promising cytotoxic effects. The findings of this study highlight the potential of novel 2,3-dihydroisoxazolo[5,4-d] pyrimidin-4(7H)-ones as promising anticancer agent, warranting further investigation for their therapeutic potential. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2024. -
Peers, Parents and Families as agents of influence on adolescents perspectives towards people with Mental Health Problems: Mental Health Professionals Views
Purpose: This study aims to explore mental health professionals views on adolescent attitudes towards their peers with mental health problems and the influence of parental, familial and societal environments on these attitudes. Design/methodology/approach: A qualitative research design was used. Semi-structured interviews were conducted with seventeen mental health professionals in Bangalore, India, with at least two years of experience working with adolescents. Thematic analysis was used to analyze the interview data. Findings: Mental health professionals reported diverse adolescent attitudes towards peers with mental health issues, ranging from support to bullying and exclusion. Family dynamics, peer influence and societal stigma were identified as significant factors shaping these attitudes. Research limitations/implications: The remote interviews during the pandemic limited access to non-verbal cues and work settings. The study focused on professionals' views from Bangalore, not capturing the diverse needs of adolescents across India. Additionally, practitioners from urban settings might not represent the challenges of their rural counterparts. The high concentration of female participants hinders generalisability. Variable interview lengths and participant openness might introduce bias, likely influenced by experience and views on mental health awareness. Practical implications: The findings underscore that adolescents' views on peer mental health are crucial for mental health professionals to design targeted interventions and support systems. Implementing programs that raise mental health awareness and reduce stigma can benefit schools and communities. Social implications: This study highlights the necessity of a holistic strategy to tackle adolescent mental health. Creating supportive peer environments, encouraging open family communication, and combating societal stigma can foster a more inclusive and mentally healthy society for adolescents. Originality/value: This study contributes to the growing body of research on adolescent mental health by providing insights into professionals views of peer attitudes. It highlights the need for interventions addressing family stigma, promoting open communication and using social media for awareness. 2024, Emerald Publishing Limited. -
ON BLOCK-RELATED DERIVED GRAPHS
This paper introduces and analyses the block-degree of a vertex and the cut-degree of a block. The block-degree of a vertex v is the number of blocks containing v. The cut-degree of a block b is the number of cut vertices of G contained in b. The block-degree sequence of cut vertices of the graph and the cut-degree sequence of the graph are defined. A few characterizations of the block-degree and cut-degree sequence of the graph are established. Given a graph, its block graph (B(G)) is a graph where each vertex represents a block, and two vertices are connected if their blocks intersect. The number of cut vertices of B(G) is determined. Further, an investigation is carried out on the traversability of B(G). A block cutpoint graph (BC(G)) of a graph represents a graph where each vertex corresponds to either a block or a cut vertex, and two vertices are connected if one represents a block and the other represents a cut vertex contained within that block. The properties of BC(G) and its iterations are studied. The graph G for which BC(G) is a perfect m-ary tree is characterized. 2024, Canadian University of Dubai. All rights reserved. -
Experimental and finite element studies on the mechanical properties of high-strength concrete using natural zeolite and additives
Addressing high carbon footprints is a critical global problem in cement production. Using environmentally friendly materials has proven to be a solution to environmental challenges. In this study, High-Strength Concrete of M60 is produced with Natural Zeolite and industrial waste materials. The combinations of 5 % zeolite and varying percentages of industrial wastes such as Silica Fume, Metakaolin, and Fly Ash are tested for mechanical properties. The laboratory test data is compared with numerical simulations to assess the accuracy and determine the error percentage for concrete strength predictions. The process involves the development of numerical solutions by ANSYS to predict strength. The developed numerical solution determines the accuracy of identifying the difference between the experimental and numerical data. The present research on the comparison of experimental and numerical data by ANSYS showed the lowest error percentage, which is acceptable for all the strength properties of concrete. 2024 -
Sensory processing sensitivity in relation to coping strategies: exploring the mediating role of depression, anxiety and stress
Existing research on sensory processing sensitivity (SPS) focuses majorly on populations involving children, those with Autism Spectrum Disorder, and those belonging to the Western countries. This study aims to contribute in bridging this gap by exploring the mediating role of Depression, Anxiety, Stress on the relationship between SPS and coping strategies in the general population, while also assessing the prevalence of these variables. Data was collected from a convenience sample of 107 participants (mean age = 20.6years, 57.9% females). Participants responses were recorded for the Highly Sensitive Person Scale (HSPS), the Depression, Anxiety, Stress Scale (DASS-21), and the Coping Strategies Inventory-Short Form (CSI-SF). Correlational and mediation analyses of SPS, coping strategies and Depression, Anxiety and Stress were done. In the sample, 31.78% of individuals were found to be Highly Sensitive Persons (HSPs). The findings revealed significant relationships between SPS, Depression, Anxiety, Stress and coping strategies. Depression and Anxiety were observed to be significant mediators. While SPS as a trait may not be inherently modifiable, our results on its association with emotion-focused disengagement coping provide insight into target dysfunctional patterns for effective management of depression, stress, and anxiety. Further research is warranted to enhance the applicability of this study. The Author(s) 2024. -
DOES COVID-19 AFFECT SHARIAH COMPLIANT STOCK? EVIDENCE FROM SELECTED OIC COUNTRIES
This study aims to examine the movements of Islamic stock markets in ten selected OIC (Organization of Islamic Cooperation) countries in relation to Covid-19 cases, providing a comprehensive analysis of market behavior during the pandemic. The countries-Saudi Arabia, Pakistan, Bangladesh, Turkey, Indonesia, Oman, Qatar, UAE, Kuwait, and Bahrain-were chosen based on their large Muslim populations. Data was collected over a one-year period from January 1, 2020, to January 31, 2021, analyzing the relationship between Covid-19 cases and Islamic stock market indices. The study employed co-integration tests to identify long-term relationships and the Vector Error Correction Model (VECM) to explore short-run dynamics. The co-integration test results show a significant long-run relationship between Covid-19 cases and Islamic stock markets in most of the selected OIC countries. Specifically, the Shariah indices in Pakistan, Bangladesh, Turkey, Qatar, UAE, Kuwait, and Bahrain have a positive and significant relationship with Covid-19 cases. Conversely, Saudi Arabia, Indonesia, and Oman exhibit a negative long-term relationship with Covid-19 cases, suggesting a different market response. These results suggest that countries with diversified economies, particularly those relying on natural resources such as oil and agriculture, were more resilient during the pandemic. This study provides novel insights into the unique responses of Islamic stock markets in OIC countries during the pandemic, highlighting regional differences in market behavior and recovery. It suggests that despite the global economic downturn, OIC countries present attractive investment opportunities, particularly due to their swift recovery and resource-based economies, offering a robust portfolio for investors during crises. 2024 by the author(s). -
Agricultural waste valorisation Novel Areca catechu L. residue blended with PVA-Chitosan for removal of chromium (VI) from water Characterization, kinetics, and isotherm studies
Arecanut, an industrial crop prevalent in tropical regions such as India, Sri Lanka, and parts of Southeast Asia, generates significant agricultural waste during processing. This study explores a waste-to-wealth approach by incorporating arecanut organic residue into Polyvinyl alcohol (PVA) - Chitosan blends via an eco-friendly continuous stirring method to develop an adsorbent film for removing chromium (VI) from water. Morphological analyses confirmed enhanced surface area, porosity, and roughness in the blended films. XRD and FTIR analyses indicated a semi-crystalline nature with a decrease in the characteristic peak intensity of PVA and chitosan, confirming the incorporation of arecanut residue. Optimal conditions identified OR-4 film, using 0.4 g of adsorbent, achieving 88.68 % removal of 173 mg/L chromium (VI) at pH 9.0, within 45 minutes at 40C. SEM images demonstrated significant surface roughness reduction before and after adsorption, confirming chromium adsorption. Kinetic studies revealed a pseudo-second-order model and adsorption isotherms confirmed film surface heterogeneity. This research advances eco-friendly materials for water purification and offers a sustainable solution for managing agricultural residues. 2024 Elsevier B.V. -
Design requirements of a spectropolarimeter for solar extreme-ultraviolet observations and characterization of a K-mirror based on Brewster's angle
Measuring the linear polarization signal in extreme-ultraviolet (EUV) spectral lines, produced by the Hanle effect, offers a promising technique for studying magnetic fields in the solar corona. The required signal-to-noise ratio for detecting the Hanle polarization signals is on the order of 101 (off-limb) to 106 (disk center). Measuring such low signals in the photon starved observations demands highly efficient instruments. In this paper, we present the design of an instrument, SpectroPOLarimeter for Extreme-ultraviolet Observations (SPOLEO), which utilizes reflective components with suitable mirror coatings and thicknesses to minimize the throughput losses. We analyze the system performance within the spectral range from 740 to 800 The K-mirror-based polarimeter model provides a polarizing power of 20%40% in this wavelength range. Based on the system throughput and polarizing power, we discuss various possibilities for achieving the required signal-to-noise ratio, along with their limitations. Due to lack of facilities for fabrication and testing in the EUV, we have calibrated a prototype of the reflection-based polarimeter setup in the laboratory at the visible wavelength of 700 nm. 2024 Optica Publishing Group. -
WSETO: wild stock exchange trading optimization algorithm enabled routing for NB-IoT tracking system
The Narrowband Internet of Things (NB-IoT) communication plays a significant role in the IoT due to the capability of generating broad exploration with the usage of limited power. Over the past few years, the Low Power Wide Area Networks (LPWAN) have been efficient in the data acquisition and remote monitoring area however they failed to generate high data rates, low latency, and the consumption of low power. To solve these problems, NB-IoT technology has developed in long-term asset tracking and it replaces the Global Positioning System (GPS) with its ubiquitous coverage. In this research, the Wild Stock Exchange Trading Optimization technique (WSETO) is proposed for a routing-based NB-IoT tracking system. The WSETO is the combination of the Wild Geese Algorithm (WGA) and SETO. By employing WSETO, the routing to the relevant target location is established effectively. The existing techniques like Low Power Asset Tracking of NB-IoT (LoPATraN), Monitoring system based on NB-IoT and BeiDou System/GPS (BDS/GPS), and Narrowband Physical Uplink Shared Channel (NPUSCH) are used to compare the WSETO approach. In rounds with a value of 2000, the WSETO demonstrates a superior location error of 0.001 in comparison to existing methods such as LoPATraN, a monitoring system utilizing NB-IoT and BDS/GPS, as well as NPUSCH. Bharati Vidyapeeth's Institute of Computer Applications and Management 2024. -
Indium oxide decorated graphitic carbon nitride/multiwalled carbon nanotubes ternary composite for supercapacitor applications
A hybrid ternary composite In2O3/g-C3N4/MWCNT (GCI) was synthesized by combining three-dimensional In2O3, two-dimensional g-C3N4, and one-dimensional MWCNTs employing a one-pot solvothermal method. The resulting In2O3/g-C3N4/MWCNTs composite leverages the combined benefits of the integration of different dimensionality materials and the synergy between its components. Integrating 1D, 2D, and 3-D materials can create hybrid structures with 3D architectures. It exhibits hierarchical porosity that provides better conductive pathways for ion transport and improves the rate performance. The distinct spatial structure of the composite with short ion diffusion paths maximizes the exposure of the active sites and enhances the conductivity, leading to superior energy storage performance. The electrochemical assessment of the In2O3/g-C3N4/MWCNTs composite exhibited a remarkable specific capacitance of 1081 F g?1 at 1 A g?1 with a commendable capacitance retention of 97.5 % at 3 A g?1 over 5000 cycles. An asymmetric supercapacitor fabricated using In2O3/g-C3N4/MWCNT//AC showcased a notable energy density of 57.5 Wh Kg?1 with an impressive power density of 2760 W Kg?1 at 1 A g?1. The outstanding electrochemical attributes of the fabricated device underscore the potential of the material for future applications in hybrid energy storage systems. 2024 Elsevier Ltd -
Microplastics in food: Occurrence, toxicity, green analytical detection methods and future challenges
The pervasive presence of microplastics (MPs) in the environment has raised significant concerns about their infiltration into the human food chain. In current review, the occurrence and distribution of MPs in various food matrices such as seafood, drinking water, fruits, vegetables, and beverages are discussed along with their potential routes of MPs entry into the human food chain. The toxicity of MPs on human health and different organs are discussed in brief. Current technological advancement and green analytical methods for the detection of MPs in food samples are compared, discussing their advantages and limitations. Green analytical methods, including stereomicroscopy, Fourier Transform Infrared spectroscopy, Raman spectroscopy, and enzymatic digestion, are evaluated for their efficacy and environmental impact. The Analytical Eco-Scale is used to assess the greenness of these methods. Challenges associated with MPs detection in food, such as complex food matrices, pretreatment methods, and variability in MPs concentrations, are addressed. 2024 The Author(s) -
Mn2(CO)10 catalyzed visible-light-promoted synthesis of 1H-pyrazole-4-carboxamides; A sustainable multi-component statergy with antibacterial and cytotoxic evaluations
Multicomponent reactions play a pivotal role in synthesizing 1H-pyrazole-4-carboxamides, underscoring its significance in sustainable organic synthesis. These compounds, valued for their diverse biological activities, have garnered substantial attention in pharmaceutical research. A facile, rapid one-pot strategy to access an extensive array of 1H-pyrazole-4-carboxamide derivatives, utilizing substituted aldehydes, cyanoacetamide, and hydrazine hydrate as substrates and a readily accessible Mn2(CO)10 as photocatalyst in EL: H2O (1:1). Among the synthesized series, products 4b, 4 g, 4k showed remarkable antibacterial activity against E coli, P aeruginosa, S. aureus in agar medium and excellent cytotoxicity with Human colorectal carcinoma (HCT-116), Liver cancer cells (Hep-G2) and breast adenocarcinoma (MCF-7) cell lines. The current method is characterized by its affordability, non-toxicity, easy access to starting materials, and notably with minimal waste generation. Additionally, remarkable aspects include its mild operating conditions, environmentally friendly nature, and the ability to accommodate a wide range of both electron-donating and electron-withdrawing groups. 2024 The Author(s) -
STOCHASTIC BEHAVIOUR OF AN ELECTRONIC SYSTEM SUBJECT TO MACHINE AND OPERATOR FAILURE
A stochastic model is developed by assuming the human (operator) redundancy in cold standby. For constructing this model, one unit is taken as electronic system which consists of hardware and software components and another unit is operator (human being). The system can be failed due to hardware failure, software failure and human failure. The failed hardware component goes under repair immediately and software goes for upgradation. The operator is subjected to failure during the manual operation. There are two separate service facilities in which one repairs/upgrades the hardware/software component of the electronic system and other gives the treatment to operator. The failure rates of components and operator are considered as constant. The repair rates of hardware/software components and human treatment rate follow arbitrary distributions with different pdfs. The state transition diagram and transition probabilities of the model are constructed by using the concepts of semi-Markov process (SMP) and regenerative point technique (RPT). These same concepts have been used for deriving the expressions (in steady state) for reliability measures or indices. The behavior of some important measures has been shown graphically by taking the particular values of the parameters. 2024, Gnedenko Forum. All rights reserved. -
Strategic design of MXene/CoFe2O4/g-C3N4 electrode for high-energy asymmetric supercapacitors
MXenes are emerging as the next-generation materials for energy storage due to their substantial surface area, exceptional conductivity, and abundant surface-terminating groups. However, the tortuous path for ion transfer within the restacked layers significantly limits the electrochemical performance of multilayered MXenes. To overcome this, interlayer spacers have been introduced. These spacers help mitigate ion diffusion barriers and enhance the accessibility of active sites, thereby improving the overall efficiency and longevity of MXene-based supercapacitors and related devices. In this study, a rational material is designed by incorporating CoFe2O4 and g-C3N4 into the layers of MXene through ultrasonication for supercapacitor application. The physicochemical properties of the synthesized materials have been comprehensively characterized using diverse techniques, revealing that MXene/CoFe2O4/g-C3N4 has successfully evolved into a multilayered structure possessing enhanced surface area, low restacking tendency, high pore diameter, and excellent pore volume. Leveraging these properties, it performs as a viable material for fabricating the working electrode with a specific capacitance (Csp) of 1506.2 F g?1 at a current density of 5 A g?1 in 3 M KOH. It shows good stability with 89 % capacitance retention over 7000 cycles. An asymmetric supercapacitor (ASC) constructed with MXene/CoFe2O4/g-C3N4 as positive electrode and activated carbon as negative electrode exhibits an energy density of 79.8 Wh Kg?1 and power density of 1343.3 W Kg?1. Furthermore, it shows a capacitive retention of 91 % over 10,000 cycles. This MXene based composite, with excellent capacitance and outstanding stability, offers an appreciable performance in the field of sustainable energy storage. 2024 Elsevier B.V. -
Dual drug co-encapsulation of bevacizumab and pemetrexed clocked polymeric nanoparticles improves antiproliferative activity and apoptosis induction in liver cancer cells
Nanoparticle (NP) enabled approaches have been employed for chemotherapeutic administration due to their capacity to regulate drug release and reduce side effects. Additionally, these methods can use several drugs concurrently and impede the proliferation of cancer cells that have developed resistance. Bevacizumab (BVZ) and pemetrexed (PEM) have demonstrated encouraging outcomes in the treatment and management of cancer. This work investigates the combined antiproliferative efficacy of BVZ and PEM co-loaded PLGA-PEG NPs (BVZ/PEM@PLGA-PEG NPs) against HepG2 liver cancerous cells. The BVZ/PEM@PLGA-PEG exhibited a sphere-shaped and consistent nanosized distribution. In addition, we evaluated the potential mechanisms for inhibiting cell growth and inducing apoptosis using DAPI staining and cell cycle study. The beneficial combined antiproliferative activity and the apoptosis pathway were detected in the HepG2 cells exposed to BVZ/PEM@PLGA-PEG NPs. Our study determined that the combinational drug treatment of BVZ/PEM@PLGA-PEG NPs has a significant effect on promoting the effectiveness of liver cancer treatment. 2024 Wiley Periodicals LLC. -
Assessment of ML techniques and suitability to predict the compressive strength of high-performance concrete (HPC)
Using industrial soil waste or secondary materials for making cement and concrete has encouraged the construction industry because it uses fewer natural resources. High-performance concrete (HPC) is recognized for its exceptional strength and sturdiness compared to conventional concrete. Accurate prediction of the compressive concentration of HPC is vital for optimizing the concrete mix design and ensuring structural integrity. Machine learning (ML) techniques have shown promise in predicting concrete properties, including compressive strength. This research focuses on various ML techniques for their suitability in predicting the compressive dilution of HPC. In this research, the Extended Deep Neural Network (EDNN) technique is used to analyze the strengths, limitations, and performance of different ML algorithms and identify the most effective methods for this specific prediction task. However, there is a problem with accuracy. Therefore, our research approach is the EDNN-centred strength characteristics prediction of HPC. In the suggested approach, data is initially acquired. Afterward, the data is pre-processed through normalization and removing missing data. Thus, the data are fed into the EDNN algorithm, which forecasts the strength characteristics of the particular mixed input designs. With the Multi-Objective Jellyfish Optimization (MOJO) technique, the value of weight is initialized in the EDNN. The activation function is the Gaussian radial function. In the experimental analysis, the implementation of the suggested EDNN is evaluated to the performance of the prevailing algorithms. When compared to current research methodologies, the proposed method performs better in this regard. The Author(s), under exclusive licence to Springer Nature Switzerland AG 2024. -
Spectroscopic Study of Late-type Emission-line Stars Using the Data from LAMOST DR6
Low-mass emission-line stars belong to various evolutionary stages, from pre-main-sequence young stars to evolved stars. In this work, we present a catalog of late-type (F0 to M9) emission-line stars from the LAMOST Data Release 6. Using the scipy package, we created a Python code that finds the emission peak at H? in all late-type stellar spectra. A data set of 38,152 late-type emission-line stars was obtained after a rigorous examination of the photometric quality flags and the signal-to-noise ratio of the spectra. Adopting well-known photometric and spectroscopic methods, we classified our sample into 438 infrared (IR) excess sources, 4669 post-main-sequence candidates, 9718 Fe/Ge/Ke sources, and 23,264 dMe sources. From a crossmatch with known databases, we found that 29,222 sources, comprising 65 IR excess sources, 7899 Fe/Ge/Ke stars, 17,533 dMe stars, and 3725 PtMS candidates, are new detections. We measured the equivalent width of the major emission lines observed in the spectra of our sample of emission-line stars. Furthermore, the trend observed in the line strengths of major emission lines over the entire late-type spectral range is analyzed. We further classified the sample into four groups based on the presence of hydrogen and calcium emission lines. This work presents a large data set of late-type emission-line stars, which can be used to study active phenomena in late-type stars. 2024 National Astronomical Observatories, CAS and IOP Publishing Ltd. All rights, including for text and data mining, AI training, and similar technologies, are reserved. -
Design and performance evaluation of a multi-load and multi-source DC-DC converter for efficient electric vehicle power systems
This paper introduces the design and comprehensive performance evaluation of a novel Multi-Load and Multi-Source DC-DC converter tailored for electric vehicle (EV) power systems. The proposed converter integrates a primary battery power source with a secondary renewable energy sourcespecifically, solar energyto enhance overall energy efficiency and reliability in EV applications. Unlike conventional multi-port converters that often suffer from cross-regulation issues and limited scalability, this converter ensures stable power distribution to various EV subsystems, including the motor, air conditioning unit, audio systems, and lighting. A key feature of the design is its ability to independently manage multiple power loads while maintaining isolated outputs, thus eliminating the inductor current imbalance that is common in traditional systems. Experimental validation using a 100W prototype demonstrated the converters ability to deliver stable 24V and 48V outputs from a 12V input, with output voltage deviations kept within 1%, significantly improving upon the 5% deviations typically seen in existing converters. Furthermore, the system achieved an impressive 93% efficiency under variable load conditions. The modular nature of the converter makes it not only suitable for EV applications but also for a broader range of industries, including renewable energy systems and industrial power supplies. This paper concludes by discussing optimization strategies for future improvements and potential scaling of the technology for commercial use in sustainable energy applications. The Author(s) 2024.