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International Conference on AeroSpace Science and Technology 2023, ICASST 2023

作者： García-Guillén, L.A. Sanchéz-Sanchéz, J.L. Ramírez-Aguilar, J.A. Ferrer-Pérez, J.A. Romo-Fuentes, J.C. Farah-Simón, A. Chávez-Moreno, R.G. Sánchez Hernández, D.C. Sánchez-Guzmán, J.A. Valdés-Galicia, J.F. Master's and Doctorate Programm in Engineering Engineering Faculty Universidad Nacional Autónoma de México CDMX Mexico Bachelor's in Aero Systems Electronics Engineering Universidad Aeronáutica en Querétaro Queretaro Mexico Advanced Technology Unit School of Engineering UNAM Queretaro Juriquilla Mexico Astronomy Institute Universidad Nacional Autónoma de México CDMX Mexico Faculty of Informatics Autonomous University of Queretaro Queretaro Juriquilla Mexico Space Program University Universidad Nacional Autónoma de México CDMX Mexico

A trend in the development of nanosatellite platforms for technology demonstration has increased in both private industry and academic projects. Communication link design plays a crucial role in the success of space missions, enabling efficient and reliable data transmission between satellites and ground stations. In this context, the use of advanced tools such as System Tool Kit (STK) has gained significant importance by enabling a comprehensive analysis of the technical and operational aspects of the communication link. In an effort to make the future design of the communications subsystem payload on a nanosatellite more efficient and accessible, this paper shows a methodology for the efficient use of STK to perform link analysis. © Published under licence by IOP Publishing Ltd.

关键词： Nanosatellites

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Adopting Centroid and Bandwidth to Shape Security Line

Adopting Centroid and Bandwidth to Shape Security Line

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International Conference of Computer Science and Information Technology

作者： Heni Ispur Pratiwi Iman Herwidiana Kartowisastro Benfano Soewito Widodo Budiharto Doctorate Program School of Computer Science Bina Nusantara University Jakarta Indonesia Computer Science Department BINUS Graduate Program Doctorate Program of Computer Science Bina Nusantara University Jakarta Indonesia Computer Engineering Department Faculty of Engineering Bina Nusantara University Jakarta Indonesia Computer Science BINUS Graduate Program Master of Computer Science Bina Nusantara University Jakarta Indonesia Computer Science Department School of Computer Science Bina Nusantara University Jakarta Indonesia

ISBN: (纸本)9798350399080

The voice patterns of gender and age have been used as speaker's identity and implied into sectors such as smart cards, healthcare, banking, and other security access controls. However, age, illness, and ambient noise factors exist challenging issues of voice changes in speech recognition systems to be resolved. This paper presents experiment results of observing those issues, and its goal was obtaining the elements of voice features to secure the speaker's identity. Mel-frequency Cepstral Coefficient (MFCC) was used to conduct observations on spectral centroid and bandwidth, it has effectively performed capturing features of individual speech signal. The experiment was conducted with data split into three groups: under 13, range 13 to 19, and above 19 years old for both male and female. The results showed that both gender under 13 have centroid voices reached to 98%, age of 13 to 19 remain with centroid reached 98% of bandwidth for male and passing over 100% for female, then above 19 for both genders speak lower with centroid 50% of bandwidth, and male above age of 19 remains to keep centroid about 50% and female changes to 95%. MFCC fits to expose the speech spectrum for the purpose of an analysis frame on specific local spectral properties of voices, and the finding is to form a security line or an individual profiling adoption.

关键词： Computer science Smart cards Shape Bandwidth Speech recognition Medical services Banking

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Phytochemistry and antimicrobial potential of off-grade white pepper (Piper nigrum L.) essential oils extracted using microwave-assisted hydro-distillation (MAHD)

Current Research in Green and Sustainable Chemistry

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Current Research in Green and Sustainable Chemistry 2025年 10卷

作者： Nurjanah, Sarifah Widyaningrum, Sekar Nurhadi, Bambang Rosalinda, S. Rienoviar Permadi, Nandang Julaeha, Euis Department of Agricultural and Biosystem Engineering Faculty of Agro-Industrial Technology Universitas Padjadjaran Jatinangor 45363 Indonesia Agroindustrial Technology Master's Program Faculty of Agro-Industrial Technology Universitas Padjadjaran Jatinangor 45363 Indonesia Department of Food Technology Faculty of Agro-Industrial Technology Universitas Padjadjaran Jatinangor 45363 Indonesia Research Center for Agroindustry National Research and Innovation Agency Bogor 16911 Indonesia Doctorate Program in Biotechnology Universitas Padjadjaran Bandung 40132 Indonesia Department of Chemistry Faculty of Mathematics and Natural Sciences Universitas Padjadjaran Jatinangor 45363 Indonesia

White pepper generally used as spice, has the main component of piperine which gives it a spicy taste and essential oils that determine its aroma. In general trade, only good pepper is traded, while off-grade that does not meet quality requirements will be wasted. This study aims to investigate the effect of extraction methods of essential oils from off-grade white pepper and the potential of its antimicrobial activity against pathogenic bacteria. The results showed that off-grade white pepper essential oils (WPEO) could be isolated by using microwave-assisted hydro-distillation (MAHD) and hydro-distillation (HD). Essential oils produced had physicochemical characteristics in accordance with the ISO 3061:2008 standard. Specifically, MAHD off-grade, MAHD grade-A, and HD WPEO had 13, 11, and 15 components, respectively. The chemical composition showed that all the extracted EO contained the main components of caryophyllene, (+)-3-carene, D-limonene, and β-pinene. The methods showed the extraction ability of monoterpene hydrocarbons by MAHD and sesquiterpene hydrocarbons by HD. In comparison, microwave-extracted essential oils had a higher limonene, while off-grade WPEO contained (+)-3-carene. The FTIR results confirmed the content of the components in the three WPEO that were investigated. All essential oils had antibacterial activity against E. coli and S. typhimurium with zone inhibition values of MAHD off-grade WPEO, MAHD grade-A WPEO, and HD off-grade WPEO against E. coli at 15.44 ± 1.68 mm, 6.72 ± 0.59 mm, and 10.17 ± 0.29 mm, as well as against S. typhimurium at 8.72 ± 1.25 mm, 8.06 ± 0.86 mm, and 8.83 ± 0.87 mm, respectively. © 2025 The Authors

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Spatial Heterogeneity of Drop Size Distribution and Its Implications for the Z-R Relationship in Mexico City

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Atmosphere 2025年第5期16卷 585-585页

作者： Roberta Karinne Mocva-Kurek Adrián Pedrozo-Acuña Miguel Angel Rico-Ramírez Program of Master and Doctorate in Engineering National Autonomous University of Mexico (UNAM) Mexico City 04510 Mexico Institute of Engineering National Autonomous University of Mexico (UNAM) Mexico City 04510 Mexico School of Civil Aerospace and Design Engineering University of Bristol Bristol BS8 1TR UK

The evaluation of raindrop size distribution (DSD) is a crucial subject in radar meteorology, as it determines the relationship between radar reflectivity (Z) and rainfall rate (R). The coefficients (a and b) of the Z-R relationship vary significantly due to several factors (e.g., climate and rainfall intensity), rendering the characterization of local DSD essential for improving radar quantitative precipitation estimation. This study used a unique network of 21 disdrometers with high spatio-temporal resolution in Mexico City to investigate changes in the local drop size distribution (DSD) resulting from seasonal fluctuations, rain rates, and topographical regions (flat urban and mountainous). The results indicate that the DSD modeling utilizing the normalized gamma distribution provides an adequate fit in Mexico City, regardless of geographical location and season. Regional variation in DSD’s slope, shape, and parameters was detected in flat urban and mountainous areas, indicating that distinct precipitation mechanisms govern rainfall in each season. Severe rain intensities (R > 20 mm/h) exhibited a more uniform and flatter DSD shape, accompanied by increased dispersion of DSD parameter values among disdrometer locations, particularly for intensities exceeding R > 60 mm/h. The coefficients a and b of the Z-R relationship exhibit significant geographic variability, dependent on the city’s topographic gradient, underscoring the necessity for regionalization of both coefficients within the metropolis.

关键词： rainfall drop size distribution disdrometer spatial variability reflectivity rain rate

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Composition and medicinal applications of Citrus essential oils: Current insights and future perspectives

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Phytomedicine Plus 2025年第3期5卷

作者： Farah Aprisza Sheelmarevaa Pramesthi Reitza Navisya Vasall Nandang Permadi Asep Harja Sarifah Nurjanah Jamaludin Al-Anshori Euis Julaeha Department of Chemistry Faculty of Mathematics and Natural Sciences Universitas Padjadjaran Jatinangor 45363 Indonesia Master’s Program in Biotechnology Graduate School Universitas Padjadjaran Bandung 40132 Indonesia Doctorate Program in Biotechnology Graduate School Universitas Padjadjaran Bandung 40132 Indonesia Department of Geophysics Faculty of Mathematics and Natural Sciences Universitas Padjadjaran Jatinangor 45363 Indonesia Department of Agriculture Engineering Faculty of Agricultural Industrial Technology Universitas Padjadjaran Jatinangor 45363 Indonesia

Citrus essential oils (CEOs) are volatile aromatic compounds derived from various plant structures, such as peels, leaves, flowers, and seeds, with unique chemical compositions influenced by species, climate, and extraction methods. CEOs, rich in terpenes and terpenoids, exhibit diverse biological activities, including antimicrobial, antioxidant, and anti-inflammatory properties. These oils have shown significant potential in combating infectious diseases and preserving food, alongside applications in the pharmaceutical, cosmetic, and perfume industries. This review summarizes current knowledge on CEOs' using PRISMA methodology focusing in chemical composition and biological activities, emphasizing their medicinal applications, such as anticancer and antimicrobial activities, and the mechanisms underlying their effects. In addition, it evaluates the benefits and challenges of their use in modern medical settings, highlighting their potential as natural agents for enhancing public health.

关键词： Bioactivity Citrus genus Essential oils Medicinal application

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An enhanced efficacy of antibacterial wound dressings impregnated with bacterial cellulose-based microencapsulated lime ( Citrus aurantiifolia ) essential oil

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Carbohydrate Polymer Technologies and Applications 2025年 10卷

作者： Euis Julaeha Irene Febbe Myrtha Karina Tatang Wahyudi Sarifah Nurjanah Pramesthi Reitza Navisya Vasall Nandang Permadi Jamaludin Al-Anshori Department of Chemistry Faculty of Mathematics and Natural Sciences Universitas Padjadjaran Jatinangor 45361 Indonesia Research Center for Environmental and Clean Technology National Research and Innovation Agency Cibinong Bogor 16911 Indonesia Research Center for Biomass and Bioproduct National Research and Innovation Agency Cibinong Bogor 16911 Indonesia Research Collaboration Center for Nanocellulose BRIN – Universitas Andalas Padang 25163 Indonesia Research Collaboration Center for Biomass and Biorefinery BRIN – Universitas Padjadjaran Jatinangor 45363 Indonesia Research Center for Advanced Materials National Research and Innovation Agency Tangerang Selatan 15310 Indonesia Department of Agriculture Engineering Faculty of Agricultural Industrial Technology Universitas Padjadjaran Jatinangor 45363 Indonesia Master’s Program in Biotechnology Graduate School Universitas Padjadjaran Bandung 40132 Indonesia Doctorate Program in Biotechnology Graduate School Universitas Padjadjaran Bandung 40132 Indonesia

Lime peel essential oil (LPO) exhibits promising antibacterial properties, yet its inherent instability limits its practical applications, necessitating effective encapsulation strategies. Microencapsulation provides protection and facilitates the controlled release of active compounds. This study developed LPO microcapsules via complex coacervation, employing gum arabic and gelatin as encapsulating agents for wound dressing applications. Process optimization identified optimal conditions at pH 4.25, 15 min stirring time, and 50 °C temperature. The microcapsules yielded 45.13 %, oil content 77.03 %, encapsulation efficiency 92.14 %, and a 44.94 % core release within 2 h, following the Avrami kinetic model ( n = 0.345). Morphological analysis revealed spherical microcapsules with an average diameter of 1.182 μm, effectively protecting LPO from thermal degradation. These microcapsules were subsequently immobilized onto bacterial cellulose produced from pineapple core fermentation using Komagataeibacter xylinus . The resulting material demonstrated potential as an antibacterial wound dressing, with inhibition zones of 11.51 mm against Staphylococcus aureus and 13.70 mm against Escherichia coli . This research presents an innovative approach to wound dressing development, integrating protective and antibacterial functions to prevent skin infection effectively.

关键词： Antibacterial Bacterial cellulose Complex coacervation C. aurantiifolia Microencapsulation

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Thermal Analysis of the Urban Canyon Based on the Variables: Orientation, Wind and Vehicular Anthropogenic Heat

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IOP Conference Series: Materials Science and engineering 2020年第1期811卷

作者： Ruth María Grajeda Rosado Elia Mercedes Alonso Guzmán Wilfrido Martínez Molina Juan Alberto Bedolla Arroyo Carlos Javier Esparza López Hugo Luis Chávez García Professor of the Universidad Veracruzana School of Architecture and student of the Inter-Institutional Doctorate Program at the Michoacan University of San Nicolas de Hidalgo Morelia Michoacan Mexico 5804 Materials Department Civil Engineering Faculty Universidad Michoacana de San Nicolas de Hidalgo Morelia Michoacan Mexico 58040 Research-Lecturer Head of Master in Bioclimatic Architecture UCO-CA25 Arquitectura y medio ambiente / Architecture and environment Research Unit Facultad de Arquitectura y Diseño Universidad de Colima

The city and its behavior in the transfer of heat, generates lines of research that study phenomena such as the Island of Urban Heat (ICU); Within its formation factors, the heat expelled by the vehicle is the least analyzed in the literature. Thanks to the Computational Fluid Dynamics (CFD) software and its validation with measurements in the field, data is acquired to examine the thermal behavior in an urban canyon based on the number of cars passing through it and the heat expelled by its engines, the speed of the wind and orientation. The results show that the temperature increases between 26% to 10% more, and the highest values are in the simulated cases with a north-south orientation, affecting the passer-by as to the energy efficiency of the buildings.

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Mapping the LST (Land Surface Temperature) with Satellite Information and Software ArcGis

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IOP Conference Series: Materials Science and engineering 2020年第1期811卷

作者： Ruth Maria Grajeda Rosado Elia Mercedes Alonso Guzmán Carlos Javier Esparza Lopez Wilfrido Martínez Molina Hugo Luis Chávez García Eduardo Limón Yedra Professor of the Universidad Veracruzana School of Architecture and student of the Inter-Institutional Doctorate Program at the Michoacán University of San Nicolas de Hidalgo Morelia Michoacan Mexico 5804 Materials Department Civil Engineering Faculty Universidad Michoacana de San Nicolas de Hidalgo Morelia Michoacan Mexico 58040 Research-Lecturer Head of Master in Bioclimatic Architecture UCO-CA25 Arquitectura y medio ambiente / Architecture and environment Research Unit Facultad de Arquitectura y Diseño Universidad de Colima Student of the Veracruz University of the Faculty of Construction Engineering and Habitat.

This document describes the procedure to calculate the LST (Land Surface Temperature). The series of steps and equations is described using the thermal bands offered by the LandSat 8 satellite and the ArcGIS program tools. Although there are other methods and tools this procedure explicitly breaks down the use of information.

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Precise Hypocenter Determination around Palu Koro Fault: a Preliminary Results

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IOP Conference Series: Earth and Environmental Science 2017年第1期62卷

作者： M. Muhammad Fawzy Ismullah Andri Dian Nugraha Mohamad Ramdhan Wandono Master Program of Geophysical Engineering Faculty of Mining and Petroleum Engineering Institut Teknologi Bandung Ganesha 10 Bandung 40132 Indonesia Global Geophysics Research Group Faculty of Mining and Petroleum Engineering Institut Teknologi Bandung Ganesha 10 Bandung 40132 Indonesia Doctorate Program of Earth Science Faculty of Earth Sciences and Technology Institut Teknologi Bandung Ganesha 10 Bandung 40132 Indonesia Agency for Meteorology Climatology and Geophysics (BMKG) Jakarta Indonesia

Sulawesi area is located in complex tectonic pattern. High seismicity activity in the middle of Sulawesi is related to Palu Koro fault (PKF). In this study, we determined precise hypocenter around PKF by applying double-difference method. We attempt to investigate of the seismicity rate, geometry of the fault and distribution of focus depth around PKF. We first re-pick P-and S-wave arrival time of the PKF events to determine the initial hypocenter location using Hypoellipse method through updated 1-D seismic velocity. Later on, we relocated the earthquake event using double-difference method. Our preliminary results show the distribution of relocated events are located around PKF and have smaller residual time than the initial location. We will enhance the hypocenter location through updating of arrival time by applying waveform cross correlation method as input for double-difference relocation.

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A PRACTICAL APPLICATION OF MULTIPHASE TRANSPORT-THEORY TO GROUNDWATER CONTAMINATION PROBLEMS

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GROUND WATER MONITORING AND REMEDIATION 1987年第1期7卷 84-92页

作者： HINCHEE, RE REISINGER, HJ Robert E. Hinchee Ph.D. P.E. is manager of Western Regional Engineering Operations for EA Engineering Science and Technology Inc. (41 Lafayette Circle Lafayette CA 94549). He holds a doctorate in civil and environmental engineering from Utah State University is a registered professional engineer and is a master's level certified hazardous materials manager. He is involved in subsurface hydrocarbon behavior research and practical assessment and remediation of contaminated sites. His experience includes investigation and design of remediation at more than 50 subsurface petroleum spill sites. H. James Reisinger II CHMM is a vice president of EA Engineering Science and Technology Inc. (Hunt Valley/Loveton Center 15 Loveton Circle Sparks MD 21152) and is responsible for all analytical services. He holds a master's degree from Millersville State University and is a master's level certified hazardous materials manager. He has developed sampling and analytical programs and provided analysis of the resulting data for more than 100 contaminated sites. He is currently responsible for a major laboratory that is in the EPA CLP program and certified in eight states.

Hydrocarbon transport in the subsurface environment occurs in several phases, chiefly the non-aqueous phase liquid (NAPL), dissolved and vapor phases. Mechanisms that influence transport include the physicochemical properties of the specific compounds present (density, vapor pressure, viscosity, hydrophobicity) and the physical and chemical properties of the subsurface environment, including geology, aquifer minerology and ground water hydrology. Hydrocarbon liquids are typically complex mixtures composed of numerous compounds, each with its own individual physicochemical and, therefore, transport properties. Examination of chemical data can provide insights into the transport mechanisms operating at a site: Ground water transport results in relative enrichment by more soluble, less hydrophobic hydrocarbon compounds as a function of distance from a spill; vapor phase transport typically results in relative enrichment in more volatile hydrocarbon *** sites at which subsurface fuel spills resulted in ground water contamination will illustrate the use of transport mechanism theory. At Site 1 a subsurface spill resulted in a NAPL plume approximately 150m (500 feet) and a dissolved hydrocarbon plume resulting from ground water transport of dissolved hydrocarbon approximately 350m (1150 feet) hydraulically downgradient of the source. At Site 2 there was a sudden subsurface fuel spill; ground water pumping with hydrocarbon recovery was begun within a week of spillage. Vapor phase transport resulted in contaminated ground water hydraulically upgradient of the source. In addition, there was cross-contamination at Site 2, probably as the result of contaminated water level gauging equipment, but the chemical characteristics of this contamination were sufficiently obvious to permit its identification. An understanding of transport mechanisms is instrumental in contamination assessment source identification, contaminant fate prediction and design of an appropriate reme

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