MAPAN最新文献

{"title":"Unveiling Spatiotemporal Dynamics of Primary Productivity through a Multi-Proxy Approach in Mumbai Harbour Bay","authors":"V. B. Yadav,&nbsp;Moushumi D. Dutta,&nbsp;Mahesh Tiwari,&nbsp;Vandana A. Pulhani,&nbsp;A. Vinod Kumar","doi":"10.1007/s12647-026-00899-1","DOIUrl":"10.1007/s12647-026-00899-1","url":null,"abstract":"<div><p>Understanding the historical trends of primary productivity in coastal marine systems is essential for assessing ecosystem health and anthropogenic impacts. This study investigates the spatiotemporal variability of primary productivity in Mumbai Harbour Bay using a multi-proxy approach, including total organic carbon (TOC), total nitrogen (TN), stable isotopes (δ¹³C and δ¹⁵N), and elemental ratios (Ca/Ti and Si/Ti ratio). The sediment core samples from two distinct locations were analyzed to reconstruct past productivity changes. Results indicate a higher accumulation of organic carbon and nitrogen in the surface sediments, suggesting increased primary productivity in recent years. The TOC/TN ratio exhibited a statistically significant negative correlation with depth (<i>p</i> &lt; 0.05), supporting the hypothesis of a progressive rise in marine productivity. The δ¹³C values ranged from − 21.54‰ to − 22.27‰, indicating marine phytoplankton as the dominant organic carbon source. A positive correlation between δ¹³C and depth (correlation coefficient: 0.53, <i>p</i> = 0.03) suggests a long-term steady increase in oceanic productivity. The Ca/Ti and Si/Ti ratios showed declining trends with depth, strengthening the evidence of enhanced primary production over time. This study highlights the importance of long-term monitoring to assess the impacts of environmental changes on marine productivity and ecosystem dynamics in urbanized coastal systems.</p></div>","PeriodicalId":689,"journal":{"name":"MAPAN","volume":"41 1","pages":"179 - 190"},"PeriodicalIF":1.3,"publicationDate":"2026-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147631664","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Load Frequency Control in the Two-Area Power System Network for the Measurement and Analysis of Various Performance Parameters Using h-GO-NN Controller Under Different Conditions","authors":"Arun Singh Rana,&nbsp;Omveer Singh,&nbsp;C. B. Vishwakarma","doi":"10.1007/s12647-025-00882-2","DOIUrl":"10.1007/s12647-025-00882-2","url":null,"abstract":"<div><p>The frequency deviations and harmonic generation of the two-area power system network under the load disturbances are major challenges of the research. Such variations in frequency also affect other parameters as well. The conventional way of the load frequency control of two-area system is too complex and need more variable for computation In order to overcome such issues, A multi-objective function has been developed by considering the effect of all disturbances. Further, the multi-objective function will be trained by a proposed intelligent controller to resolve such problems. The proposed intelligent controller has been called as heuristic grasshopper optimization neural network (h-GO-NN) controller, which is developed by combining the two topologies, namely the grasshopper optimization algorithm and artificial neural network. The proposed controller is simple, and need less computation variables, which is the novelty of the research. The first step in the entire analysis is the mathematical modelling of the different generating units in each area, including conventional sources (CS), wind turbines (WTS), and solar photovoltaic (PV), all of sources are connected to the common grid. The h-GO-NN controller is used to simulate two area networks in order to examine the different parameters. A number of performance parameters will be measured, including voltage deviation, frequency deviations, area control error (ACE), and total harmonic distortion (THD) of grid voltage. Variable load disturbance, variable solar irradiation, and variable wind operation are the three scenarios in which all such evaluations will be examined. At the end, it is observed that the least frequency deviation, least voltage deviation, minimum ACE and minimum THD (%) have been attained with the proposed h-GO-NN controller in contrast to existing techniques which is one of greatest achievement of proposed controller.</p></div>","PeriodicalId":689,"journal":{"name":"MAPAN","volume":"41 1","pages":"165 - 178"},"PeriodicalIF":1.3,"publicationDate":"2026-02-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147631854","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Integration of Galileo and PPP-AR Enhancements to Improve GNSS Accuracy from India Through Updated MADOCA-PPP","authors":"Aiswarya S. Pillai,&nbsp;Somnath Mahato,&nbsp;Mrinal Goswami,&nbsp;Bibekananda Panda,&nbsp;Surajit Kundu","doi":"10.1007/s12647-026-00896-4","DOIUrl":"10.1007/s12647-026-00896-4","url":null,"abstract":"<div><p>This study evaluates the real-time performance of MADOCA-based Precise Point Positioning (PPP) services in Eastern India, using a low-cost, SWaP-C-optimized GNSS module, corrections were received via MADOCA-PPP over IP using the MADWIN/NTRIP client service, rather than via broadcast L6 signals. Both the legacy MADOCA correction stream (GPS + GLONASS + QZSS) and the updated version (GPS + GLONASS + Galileo + QZSS with PPP-AR) were assessed over 14,400 epochs and benchmarked against post processed CSRS-PPP service. This is the first report from India on the performance of updated MADOCA PPP service, offering critical insights into its operational potential in the region. Results show that the updated MADOCA configuration significantly improves convergence time, horizontal accuracy, and positioning stability. Key metrics, including 2DRMS, CEP, and MRSE, confirm reductions in horizontal and vertical errors of up to 75% in 2DRMS compared to the legacy model. CSRS-PPP, utilizing post-processed IGS Final products, achieved the highest precision with sub-centimetre accuracy across all dimensions. Signal quality analysis indicated robust carrier-to-noise ratios across GPS, Galileo, and QZSS, supporting reliable satellite tracking and noise resilience. Time series and error distribution analyses further validated the superior performance of the updated MADOCA solution. This research highlights the viability of cost-effective, real-time high-precision GNSS positioning in India using compact hardware, supporting applications in defense, surveying, navigation, and infrastructure monitoring. It also underscores the value of regional PPP customization to overcome environmental and infrastructure challenges, paving the way for scalable deployment of GNSS technologies in resource-constrained settings.</p></div>","PeriodicalId":689,"journal":{"name":"MAPAN","volume":"41 1","pages":"397 - 413"},"PeriodicalIF":1.3,"publicationDate":"2026-02-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147631794","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Microwave Time Domain Reflectometry Analysis and Characterization of Electromagnetic Field Generating Structures","authors":"Abhinav Mishra,&nbsp;Satya Kesh Dubey","doi":"10.1007/s12647-025-00883-1","DOIUrl":"10.1007/s12647-025-00883-1","url":null,"abstract":"<div><p>This study presents the essential features of Time Domain Reflectometry (TDR) measurements, emphasizing analysis using the time-domain mode of a Vector Network Analyzer (VNA). It focuses on characterizing electromagnetic field generating structures, including TEM cell, GTEM cell and stripline, which are critical for precise E-field measurements. TDR provides accurate evaluation of important parameters such as linearity and sensitivity to meet various standards compliances. Moreover, certain reflective behavior measurement outcomes that try to describe the impedance behavior of transverse are identified by some reflective measurement outcomes TEM/GTEM/Stripline cells are displayed by our owners using a VNA operating in time-domain mode.</p></div>","PeriodicalId":689,"journal":{"name":"MAPAN","volume":"41 1","pages":"155 - 163"},"PeriodicalIF":1.3,"publicationDate":"2026-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147631763","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Design and Development of Low-Cost Sensor for Identification of Adulterated Milk","authors":"D. K. Chaturvedi,&nbsp;Achal Maharaj Kishore Mogla","doi":"10.1007/s12647-026-00889-3","DOIUrl":"10.1007/s12647-026-00889-3","url":null,"abstract":"<div><p>Milk is the perfect food for all human beings. Because it provides essential fatty acids, vitamins, inorganic elements, water, and amino acids. As per a research statistic out of milk produced by 4500 living mammalian species, only about 180 have undergone significant milk investigations, and approximately 50 are considered reliable sources of information due to adequate sampling and coverage of the lactation period. As per available data Uttar Pradesh is the largest milk producing state in India. 319 lakh metric tonnes of milk per annum was produced in the year 2022–2023. On the other hand, Per Capita Milk consumption as per records in Uttar Pradesh (U.P) is approximately 426 metric tons of milk. Therefore, the production is less than the consumption value. This has led to the serious problem of adulteration as people need to consume milk because of the various benefits that it offers. Prevention of adulteration of milk is one of the best solutions. Milk can be adulterated free only if the input is of good quality, then the output shall also be good provided that no interference or manhandling is done midway till the milk reaches the consumer. In this paper, an experimental set up is design and developed for identifying the milk adulteration using electrical parameters and colored light passed through it. The identification of milk adulteration is done using electrical resistance measurement and amount of colored light (red, green and blue) passed through the milk. This method is cheap and effective. The results are compared for different adulterated milks and pure milk.</p></div>","PeriodicalId":689,"journal":{"name":"MAPAN","volume":"41 1","pages":"1 - 10"},"PeriodicalIF":1.3,"publicationDate":"2026-01-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147631686","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fault Diagnosis in Roller Bearings by Using an Advanced Artificial Intelligence-Based Metrology","authors":"Ekta Yadav,&nbsp;V. K. Chawla,&nbsp; Navdeep,&nbsp;Sanjay Yadav","doi":"10.1007/s12647-026-00887-5","DOIUrl":"10.1007/s12647-026-00887-5","url":null,"abstract":"<div><p>In this study, a new image segmentation framework for infrared thermographic inspection, utilizing texture encoding integrated with thermal constraints, is developed to enhance defect localization. The method, namely, advanced local binary pattern with thermal constraint (ALBP-TC), incorporates median-filtered grayscale pre-processing, ALBP-based texture feature extraction, and adaptive thermal thresholding. These elements are combined by using an extraction and adaptive thresholding, and the segmentation accuracy is improved by using a weighted approach. To automate parameter selection and maximize diagnostic performance, a non-dominated sorting genetic algorithm-II (NSGA-II) is employed to optimize thermal threshold (<span>({T}_{t})</span>) and fusion weight (<span>(omega)</span>) by using multi-objective criteria by considering multi-performance parameters, namely, Accuracy, Dice similarity index (DSI), and Jaccard similarity index (JSI), etc. The experimental validation of thermal images of roller bearings demonstrates a robust condition monitoring ability by achieving 99.16% accuracy, 100% sensitivity, and 99.15% specificity, with DSI and JSI measures of 82% and 69.48%, respectively. A comparative analysis of the proposed method with other experimental methods from recent literature confirms the superiority of the proposed method in terms of accuracy and spatial coherence.</p></div>","PeriodicalId":689,"journal":{"name":"MAPAN","volume":"41 1","pages":"131 - 153"},"PeriodicalIF":1.3,"publicationDate":"2026-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147631839","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Design and Implementation of a Low-Cost Device to Monitor the Real-Time Presence of CO and CO2 in Ambient Air and Prediction of its Pollution Level using TinyML","authors":"Abir Lal Dutta,&nbsp;Tapajit Mukherjee,&nbsp;Jayee Sinha","doi":"10.1007/s12647-026-00890-w","DOIUrl":"10.1007/s12647-026-00890-w","url":null,"abstract":"<div><p>In recent times, the air pollution rates are radically expanding over all the nations and requires a financially effective solution. This paper leverages Internet of Things (IoT) technology to develop a cutting-edge air quality monitoring system which can lead to a concise monitoring device manufacturing process. The system features a network of low-cost, portable gas sensors used to measure pollutants like carbon monoxide (CO) in addition to carbon dioxide (CO₂) levels in order to check their concentrations within the safe range in the surrounding air. A display is connected to the setup, which makes the system more convenient in terms of live data visualization and air quality tracking. The IoT module which consists of ESP32 microcontroller enables real-time data transmission to a cloud-based platform, which is used by advanced analytics and machine learning algorithms to provide predictions based on the dataset acquired. Our set-up offers high-resolution data for targeted interventions in a scalable and cost-effective deployment which can be integrated with smart city infrastructures. By demonstrating the effectiveness of IoT-based air quality monitoring, the proposed set-up will be able to optimize pollution mitigation strategies in metropolitan cities.</p></div>","PeriodicalId":689,"journal":{"name":"MAPAN","volume":"41 1","pages":"119 - 129"},"PeriodicalIF":1.3,"publicationDate":"2026-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147631724","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Selection of Inductance Standard for a Comparison Using Statistical Methods Based on Accurate Measurements","authors":"Oleh Velychko,&nbsp;Sergii Kursin,&nbsp;Viktoriia Shvedova,&nbsp;Tetyana Gordiyenko","doi":"10.1007/s12647-025-00876-0","DOIUrl":"10.1007/s12647-025-00876-0","url":null,"abstract":"<div><p>National standards must be as accurate and stable as possible to ensure accurate measurements over a long period of time. The choice of travelling standards for comparisons is based on many years of research and the study of the behavior of such standards. The availability of a group of specially designed precision inductance standards in a special thermostat at the national laboratory needed long-term studies of their characteristics before using one of them in comparison of standards. The laboratory has been conducting regular long-term stability studies of the investigated inductance standards of 100 mH at frequency of 1000 Hz since 2009, which confirm their stability of no more than 10μH per year. The measurement studied standards were carried out using a special measuring setup for calibrating inductance standards with expanded uncertainty at 35 µH/H. To select the most optimal inductance standard for comparisons, it is advisable that the average results of a single standard be close to the average value of all standards and that it be stable over a long period of time. Drift analysis of the studied standards showed their good stability during 2013–2023, which was confirmed by the Abbe test. The analysis of the results of the detrended sample made it possible to establish the consistency of the standard deviations of the results of the reproduction of the inductance of the studied standards using Student’s and Cochrane tests.</p></div>","PeriodicalId":689,"journal":{"name":"MAPAN","volume":"41 1","pages":"109 - 118"},"PeriodicalIF":1.3,"publicationDate":"2026-01-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147631753","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Generalized Bayesian Estimation of Survival Time Distributions Using Informative and Non-informative Priors Based on Fuzzy Information","authors":"Muhammad Shafiq,&nbsp;Saqib Waheed,&nbsp;Umair Khalil,&nbsp;Tmader Alballa,&nbsp;Hamiden Abd El-Wahed Khalifa","doi":"10.1007/s12647-025-00877-z","DOIUrl":"10.1007/s12647-025-00877-z","url":null,"abstract":"<div><p>In almost every field of science, the decision about the population is based on the sampled data, usually recorded in the form of precise numbers. Statistics provide solid methods and models to streamline the raw observations into useful information. Over the decades, lifetime observations have been recorded as precise numbers, and a significant number of models have been developed to cover the random uncertainty in the obtained lifetime observations in life and engineering sciences. But with advancements in technology, a large sample of lifetime observations became difficult; therefore, Bayesian approaches are used for small sample sizes. Furthermore, advanced metrology suggests that exact measurements of continuous phenomena are not possible, and measurements also have another kind of uncertainty called fuzziness. Therefore, for the best possible inference, it is essential to cover all possible uncertainties. For this reason, lifetimes should be measured and recorded using up-to-date fuzzy numbers. This study aims to develop the Bayesian parameter estimators for important lifetime models to cover both uncertainties, i.e., fuzziness and random variation. To integrate all the available information in the suggested estimators, generalized Bayesian estimators for lifetime distributions, i.e. exponential and gamma distributions, are proposed, using fuzzy informative and non-informative priors along with fuzzy lifetimes and fuzzy hyperparameters. The proposed estimators are considerably useful compared to the classical estimators because they address both uncertainties, <b>i.e. random variation and fuzziness</b> present in lifetime observations, whereas the classical estimators only cover one, <b>only random variation</b>. Furthermore, interesting results are obtained that show the parameters of posterior density have a much increased fuzziness as compared to the fuzziness in lifetimes and the fuzziness in hyperparameters. These results provide strong evidence that fuzziness in lifetime observations should not be ignored. Ignoring the fuzziness could result in misleading inference. Consequently, it is essential to consider and incorporate this fuzziness when making inferences or evaluating lifetime data.</p></div>","PeriodicalId":689,"journal":{"name":"MAPAN","volume":"41 1","pages":"97 - 108"},"PeriodicalIF":1.3,"publicationDate":"2026-01-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147631677","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Estimation and Prediction of Long-Term Drift of the High Resistance Standards","authors":"Oleh Velychko,&nbsp;Denys Nikitenko,&nbsp;Sergii Kursin,&nbsp;Tetyana Gordiyenko,&nbsp;Vasyl Dovhan","doi":"10.1007/s12647-025-00880-4","DOIUrl":"10.1007/s12647-025-00880-4","url":null,"abstract":"<div><p>The drift of the standards can significantly affect the calibration results of measuring instruments, so such standards require regular calibration using more accurate standards. Taking into account historical data on the drift of the reference standard allows us to assess how its drift can affect the calibration results of other measuring instruments. A requirement is set for reference standards for their stability—the limit of change in the measured value during the intercalibration interval. The article presents the results of assessing the long-term drift of reference resistance standards of direct current (DC) with nominal values of 1 MΩ, 10 MΩ, 100 MΩ and 1000 MΩ using polynomial regression of 1–3 orders. Expanded measurement uncertainties for calibration of DC resistance standards are estimated from 6 to 9 μΩ/Ω. The results of the latest calibrations of these resistance standards are used to predict the time drift for future calibrations. The predicted time drift period for the measurements of 3 years was chosen taking into account their intercalibration interval of 1–2 years. The difference between the obtained predicted values is from 2 to 6 μΩ/Ω from the average values of the standards used. The predicted values of the standards were simulated using the Monte Carlo method for linear and exponential regressions. Those values differ slightly from the obtained data using the Monte Carlo method, but are within the established confidence interval.</p></div>","PeriodicalId":689,"journal":{"name":"MAPAN","volume":"41 1","pages":"83 - 96"},"PeriodicalIF":1.3,"publicationDate":"2026-01-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147631851","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}