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Machine-Type Communications, the Internet of Things, and Satellite Networks: Drivers, Use Cases, and Requirements
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The integration of nonterrestrial MTC and satellite communication is a paradigm change in the IoT connectivity – known as SIoT . The combined technology enables ubiquitous coverage and service for numerous IoT applications. This chapter scrutinizes future satellite-based MTC key drivers, use cases, and their requirements and implications. Specifically, we discuss the recent progress of satellite IoT and its critical social, economic, and environmental drivers. Then, we discuss, analyze, and classify the IoT use cases and pinpoint prominent applications. Departing from these, we revisit the MTC and satellite communication KPIs and propose a novel concept of KVIs for satellite-based MTC systems.Summary
The integration of nonterrestrial MTC and satellite communication is a paradigm change in the IoT connectivity – known as SIoT . The combined technology enables ubiquitous coverage and service for numerous IoT applications. This chapter scrutinizes future satellite-based MTC key drivers, use cases, and their requirements and implications. Specifically, we discuss the recent progress of satellite IoT and its critical social, economic, and environmental drivers. Then, we discuss, analyze, and classify the IoT use cases and pinpoint prominent applications. Departing from these, we revisit the MTC and satellite communication KPIs and propose a novel concept of KVIs for satellite-based MTC systems
Regulation and Spectrum Opportunities in Integrated Machine-Type Communication and Satellite Networks
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This chapter focuses on all things related to spectrum, what it is, and how it is regulated and shared among different stakeholders and services for both terrestrial and satellite MTC transmissions. First, the basics of regulations and regulatory work are introduced to understand their scope and reach. The state-of-the-art spectrum management techniques are then presented, for each spectrum access regime, exclusive, primary/secondary, and unlicensed. The focus is on dynamic techniques. Then, the current frequency allocations and limitations for MTC networks are listed. The future of frequency allocations and regulations for MTC and satellite networks are also presented. The chapter finishes with spectrum management challenges, opportunities, trends, and research topics going toward 6G.Summary
This chapter focuses on all things related to spectrum, what it is, and how it is regulated and shared among different stakeholders and services for both terrestrial and satellite MTC transmissions. First, the basics of regulations and regulatory work are introduced to understand their scope and reach. The state-of-the-art spectrum management techniques are then presented, for each spectrum access regime, exclusive, primary/secondary, and unlicensed. The focus is on dynamic techniques. Then, the current frequency allocations and limitations for MTC networks are listed. The future of frequency allocations and regulations for MTC and satellite networks are also presented. The chapter finishes with spectrum management challenges, opportunities, trends, and research topics going toward 6G
Steric Hindrance-Induced Amorphous Lithium Sulfide Deposition Accelerates Sulfur Redox Kinetics in Lithium-Sulfur Batteries
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Lithium–sulfur (Li─S) batteries are promising candidates for next-generation energy storage due to their ultrahigh theoretical energy density. However, their practical application is severely hindered by the sluggish conversion kinetics, particularly during the crystalline lithium sulfide (Li2S) formation stage. Herein, a steric hindrance-mediated engineering strategy is proposed that induces an amorphous Li2S deposition process, effectively boosting the sulfur redox kinetics in Li─S batteries. By introducing benzo-15-crown-5 (B15C5) as an electrolyte additive, a strong coordination between B15C5 and lithium ion (Li+) is established, which creates spatial confinement around Li2S and disrupts the crystallinity of Li2S during its deposition. Synchrotron pair distribution function analysis combined with in situ X-ray diffraction reveals that the deposited Li2S with B15C5 exhibits significant local disorder with irregular Li─S bond oscillations, confirming the generation of an amorphous phase. This strategy not only ensures a uniform Li2S layer at the cathode/electrolyte interface but also lowers the energy barrier of sulfur species at the molecular scale, enabling the Li─S batteries with excellent cycling stability and overall enhanced sulfur reaction kinetics. This work provides a novel pathway for overcoming the intrinsic limitations of sluggish cathode conversion kinetics of Li─S batteries, paving the way for their practical deployment in high-performance energy storage applications.Abstract
Lithium–sulfur (Li─S) batteries are promising candidates for next-generation energy storage due to their ultrahigh theoretical energy density. However, their practical application is severely hindered by the sluggish conversion kinetics, particularly during the crystalline lithium sulfide (Li2S) formation stage. Herein, a steric hindrance-mediated engineering strategy is proposed that induces an amorphous Li2S deposition process, effectively boosting the sulfur redox kinetics in Li─S batteries. By introducing benzo-15-crown-5 (B15C5) as an electrolyte additive, a strong coordination between B15C5 and lithium ion (Li+) is established, which creates spatial confinement around Li2S and disrupts the crystallinity of Li2S during its deposition. Synchrotron pair distribution function analysis combined with in situ X-ray diffraction reveals that the deposited Li2S with B15C5 exhibits significant local disorder with irregular Li─S bond oscillations, confirming the generation of an amorphous phase. This strategy not only ensures a uniform Li2S layer at the cathode/electrolyte interface but also lowers the energy barrier of sulfur species at the molecular scale, enabling the Li─S batteries with excellent cycling stability and overall enhanced sulfur reaction kinetics. This work provides a novel pathway for overcoming the intrinsic limitations of sluggish cathode conversion kinetics of Li─S batteries, paving the way for their practical deployment in high-performance energy storage applications
Drying kinetics of CeO2-ZrO2 ceramic powders under microwave heating based on a thin-layer drying model
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Volume change of ZrO2 during martensitic phase transformation can cause cracking of material and limit the application of ZrO2.Agglomeration of CeO2-ZrO2 ceramic powders can be effectively reduced by choosing the correct drying method. Microwave drying of CeO2-ZrO2 powder can effectively reduce the cracking of zirconia materials and improve powder uniformity. Microwave heating is used to dry CeO2-ZrO2 ceramic powders, and results demonstrate that Modified Page fits experimental data rather well. FT-IR spectra revealed a remarkable decrease in the intensity of the -OH bond's stretching vibration peak, and H-O-H bond's bending vibration. Utilizing Fick's second law, the diffusion coefficient of water molecules in CeO2-ZrO2 ceramic powders with a mass of 20 g and a moisture content of 6.6 % is calculated to be 5.820 × 10−15 m2/s under microwave power of 400 W. Experimental results prove that microwave heating has low activation energy, improves drying efficiency, and realizes fast and efficient drying.Abstract
Volume change of ZrO2 during martensitic phase transformation can cause cracking of material and limit the application of ZrO2.Agglomeration of CeO2-ZrO2 ceramic powders can be effectively reduced by choosing the correct drying method. Microwave drying of CeO2-ZrO2 powder can effectively reduce the cracking of zirconia materials and improve powder uniformity. Microwave heating is used to dry CeO2-ZrO2 ceramic powders, and results demonstrate that Modified Page fits experimental data rather well. FT-IR spectra revealed a remarkable decrease in the intensity of the -OH bond's stretching vibration peak, and H-O-H bond's bending vibration. Utilizing Fick's second law, the diffusion coefficient of water molecules in CeO2-ZrO2 ceramic powders with a mass of 20 g and a moisture content of 6.6 % is calculated to be 5.820 × 10−15 m2/s under microwave power of 400 W. Experimental results prove that microwave heating has low activation energy, improves drying efficiency, and realizes fast and efficient drying
Region
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‘Region’, used both as a spatial scale and a parameter for geographical thinking, has remained a key concept within geographical research for over a hundred years. This chapter discusses the historical development of regional geographical research on literature, showing how regional literary geography has combined topics and questions from other fields of geographical research. Attention is paid to how epistemological changes and challenges have affected regional literary geography and how regionalism, narrated regional identities, and a sense of regional belonging have turned into research topics for literary geography. The chapter also discusses how regionality should be understood in terms of spatial scales and how regional writing functions as a cultural institution through which the discourses of spatial otherness are constructed and maintained. This chapter illustrates how the idea of the region with several conceptual variations is still a topical issue and theoretical framework in the geographical studies of fiction.Abstract
‘Region’, used both as a spatial scale and a parameter for geographical thinking, has remained a key concept within geographical research for over a hundred years. This chapter discusses the historical development of regional geographical research on literature, showing how regional literary geography has combined topics and questions from other fields of geographical research. Attention is paid to how epistemological changes and challenges have affected regional literary geography and how regionalism, narrated regional identities, and a sense of regional belonging have turned into research topics for literary geography. The chapter also discusses how regionality should be understood in terms of spatial scales and how regional writing functions as a cultural institution through which the discourses of spatial otherness are constructed and maintained. This chapter illustrates how the idea of the region with several conceptual variations is still a topical issue and theoretical framework in the geographical studies of fiction
Rural Micro-entrepreneurship and Asset Management Support by a Locally Embedded Civil Society Organization: An Exploratory Case Study in Pakistan
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This chapter is one of the pioneering academic endeavors to assess asset management support offered by locally embedded civil society organizations (CSOs) to rural micro-entrepreneurs in the emerging economy context of Pakistan. Most of the existing research on micro-entrepreneurship financing has so far mostly focused on startup financing and access to capital (primarily loans). However, a significant challenge for micro-entrepreneurs, particularly those operating in emerging economies’ rural contexts, is asset management in the pre-operational, operational, and post-operational phases of startup to ensure their businesses may survive and thrive. The current chapter analyzes the single in-depth case study of a local CSO (Khushal Dastkaar) active in rural settings (Chakwal in Punjab province of Pakistan) for micro-entrepreneurship development. Being locally embedded, the case CSO can undertake continuous monitoring and offer asset management support for home-based startups. We present the details of four micro-entrepreneurs as examples to specify the peculiarities of the support mechanisms and associated processes. The findings revealed the critical role of asset management support in ensuring the continued operation of these micro-entrepreneurs. Along with ensuring viable operations in the main line of business, innovative use of bought assets and diversification by sample micro-entrepreneurs was observed and the support offered by the locally embedded CSO was vital in this concern.Abstract
This chapter is one of the pioneering academic endeavors to assess asset management support offered by locally embedded civil society organizations (CSOs) to rural micro-entrepreneurs in the emerging economy context of Pakistan. Most of the existing research on micro-entrepreneurship financing has so far mostly focused on startup financing and access to capital (primarily loans). However, a significant challenge for micro-entrepreneurs, particularly those operating in emerging economies’ rural contexts, is asset management in the pre-operational, operational, and post-operational phases of startup to ensure their businesses may survive and thrive. The current chapter analyzes the single in-depth case study of a local CSO (Khushal Dastkaar) active in rural settings (Chakwal in Punjab province of Pakistan) for micro-entrepreneurship development. Being locally embedded, the case CSO can undertake continuous monitoring and offer asset management support for home-based startups. We present the details of four micro-entrepreneurs as examples to specify the peculiarities of the support mechanisms and associated processes. The findings revealed the critical role of asset management support in ensuring the continued operation of these micro-entrepreneurs. Along with ensuring viable operations in the main line of business, innovative use of bought assets and diversification by sample micro-entrepreneurs was observed and the support offered by the locally embedded CSO was vital in this concern
A comprehensive study on crystal structure, phase compositions of the BiVO4-LaVO4 binary dielectric ceramic system and a typical design of dielectric resonator antenna for C-band applications
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Novel multi-component (Bi1-xLax)VO4 (BLVOx) (0.05 ≤ x ≤ 0.9) solid-solution/composite ceramics crystal structures, phase compositions as well as its applications in the C-band dielectric resonator antenna have been designed and investigated. With the increased substitution of La3+, phase transitions among the monoclinic scheelite (mBiVO4), tetragonal zircon (zt(La,Bi)VO4) and monoclinic monazite (mLaVO4), driven by the compositional changes, were detected. La3+ played an essential role in the optimization of the dielectric properties of BLVOx. The measured Q × f values at the microwave band are considerably larger around the range of compositions forming the zircon phase and reached the maximum value (12,800 GHz) at pure zircon phase (x = 0.5), demonstrating that the impact of zircon structure on the intrinsic loss should not be disregarded and is beneficial for low dielectric loss. Meanwhile, the εr and TCF values could be tuned by regulating the concentration ratio of Bi3+/La3+ to obtain composites or solid-solutions with appropriate and near-zero TCF values. Additionally, a cylindrical dielectric resonator antenna (CDRA) of BVLO0.5 ceramic was designed with high simulated radiation efficiency (99.8%) and gain (4.58 dBi) at the center frequency (6.73 GHz), indicating its potential application in C-band because of its tunable permittivity and low-loss.Abstract
Novel multi-component (Bi1-xLax)VO4 (BLVOx) (0.05 ≤ x ≤ 0.9) solid-solution/composite ceramics crystal structures, phase compositions as well as its applications in the C-band dielectric resonator antenna have been designed and investigated. With the increased substitution of La3+, phase transitions among the monoclinic scheelite (mBiVO4), tetragonal zircon (zt(La,Bi)VO4) and monoclinic monazite (mLaVO4), driven by the compositional changes, were detected. La3+ played an essential role in the optimization of the dielectric properties of BLVOx. The measured Q × f values at the microwave band are considerably larger around the range of compositions forming the zircon phase and reached the maximum value (12,800 GHz) at pure zircon phase (x = 0.5), demonstrating that the impact of zircon structure on the intrinsic loss should not be disregarded and is beneficial for low dielectric loss. Meanwhile, the εr and TCF values could be tuned by regulating the concentration ratio of Bi3+/La3+ to obtain composites or solid-solutions with appropriate and near-zero TCF values. Additionally, a cylindrical dielectric resonator antenna (CDRA) of BVLO0.5 ceramic was designed with high simulated radiation efficiency (99.8%) and gain (4.58 dBi) at the center frequency (6.73 GHz), indicating its potential application in C-band because of its tunable permittivity and low-loss
Employee Mental Workload Classification in Industrial Workplaces: A Machine Learning Approach
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Employees at industrial workplaces are expected to produce labour of a certain standard. They are instructed to improve their quality of work, and this may take a toll on their mental health. Mental workload directly affects employees’ performance, productivity, and well-being. Therefore, this paper conducts a comparative study for the classification of mental workload where a mental workload dataset is subjected to four machine learning classification models-Naïve Bayes, Extreme Gradient Boosting, Support Vector Machine and K-Nearest Neighbour. Their performance is measured against the performance metrics-accuracy, precision, recall and f1-score. Before synthetic minority oversampling method Support Vector Machine performed the best with 90.41% accuracy and K-Nearest Neighbour performed the best with 98.61% accuracy after Synthetic Method of Oversampling Technique.Abstract
Employees at industrial workplaces are expected to produce labour of a certain standard. They are instructed to improve their quality of work, and this may take a toll on their mental health. Mental workload directly affects employees’ performance, productivity, and well-being. Therefore, this paper conducts a comparative study for the classification of mental workload where a mental workload dataset is subjected to four machine learning classification models-Naïve Bayes, Extreme Gradient Boosting, Support Vector Machine and K-Nearest Neighbour. Their performance is measured against the performance metrics-accuracy, precision, recall and f1-score. Before synthetic minority oversampling method Support Vector Machine performed the best with 90.41% accuracy and K-Nearest Neighbour performed the best with 98.61% accuracy after Synthetic Method of Oversampling Technique
Sentiment Analysis and Innovative Recommender System: Enhancing Goodreads Book Discovery Using Hybrid Collaborative and Content Based Filtering
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This study addresses the challenge of finding suitable books in the digital age of education, where information overload makes manual book selection difficult. It aims to analyze reviewer sentiment on Goodreads and develop a recommendation algorithm based on readers’ preferences. The study employs sentiment analysis and compares three recommender algorithms: Content-Based, Collaborative filtering, and Hybrid filtering. Goodreads data is collected using a web scraper, and the results indicate Hybrid filtering as the most effective model, outperforming others in metrics like RMSE, MSE, precision, and recall. Further optimization with the Apriori model can enhance Hybrid filtering’s accuracy and recommendation breadth, reducing system errors.Abstract
This study addresses the challenge of finding suitable books in the digital age of education, where information overload makes manual book selection difficult. It aims to analyze reviewer sentiment on Goodreads and develop a recommendation algorithm based on readers’ preferences. The study employs sentiment analysis and compares three recommender algorithms: Content-Based, Collaborative filtering, and Hybrid filtering. Goodreads data is collected using a web scraper, and the results indicate Hybrid filtering as the most effective model, outperforming others in metrics like RMSE, MSE, precision, and recall. Further optimization with the Apriori model can enhance Hybrid filtering’s accuracy and recommendation breadth, reducing system errors
ZnO-CdS-Ag2S double S-scheme heterojunctions with significant hydrogen evolution reaction and dye degradation properties
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Here in, we report a new methodology for the fabrication of free template ternary ZnO-CdS-Ag2S nanohybrids with superior photocatalyst properties for the hydrogen evolution reaction (HER) and dye degradation. Firstly, ZnO nanorods (NRs) were synthesized using a solvothermal method and used as a seed template for the growth of CdS-Ag2S QDs. The CdS-Ag2S QDs were grown using two different methods of microwave irradiation and photochemical treatment using thioglycolic acid (TGA) as both capping agent and digestive reactant. Structural characterizations proved the formation of the ternary structure with both methods of synthesis. XPS analyses revealed that photochemical approach results in the formation of a ternary composite with higher ZnO nanoparticles concentration. Electrochemical studies inferred that samples prepared using photochemical treatment have the least of charge transfer resistance, large surface area of 132 m2/g, large electrochemical surface area and higher electrochemical performance. Linear sweep voltammetry obtained current densities of magnitude of 100 mA cm−2 at bias −0.475 V vs. RHE, onset potential of −0.238 V, and Tafel slope of 45 mV/dec. Moreover, samples prepared using photochemical approach showed also high cyclic HER stability and reproducibility of the same results from the same ink after storing for six months. This method of synthesis can be applied for the synthesis of multi-functional ternary metal oxide-QD-QD nanocomposites for energy conversion applications. A S-scheme band diagram is suggested to infer the internal charge separation mechanism and high HER and photocatalyst activities of the ternary compound.Abstract
Here in, we report a new methodology for the fabrication of free template ternary ZnO-CdS-Ag2S nanohybrids with superior photocatalyst properties for the hydrogen evolution reaction (HER) and dye degradation. Firstly, ZnO nanorods (NRs) were synthesized using a solvothermal method and used as a seed template for the growth of CdS-Ag2S QDs. The CdS-Ag2S QDs were grown using two different methods of microwave irradiation and photochemical treatment using thioglycolic acid (TGA) as both capping agent and digestive reactant. Structural characterizations proved the formation of the ternary structure with both methods of synthesis. XPS analyses revealed that photochemical approach results in the formation of a ternary composite with higher ZnO nanoparticles concentration. Electrochemical studies inferred that samples prepared using photochemical treatment have the least of charge transfer resistance, large surface area of 132 m2/g, large electrochemical surface area and higher electrochemical performance. Linear sweep voltammetry obtained current densities of magnitude of 100 mA cm−2 at bias −0.475 V vs. RHE, onset potential of −0.238 V, and Tafel slope of 45 mV/dec. Moreover, samples prepared using photochemical approach showed also high cyclic HER stability and reproducibility of the same results from the same ink after storing for six months. This method of synthesis can be applied for the synthesis of multi-functional ternary metal oxide-QD-QD nanocomposites for energy conversion applications. A S-scheme band diagram is suggested to infer the internal charge separation mechanism and high HER and photocatalyst activities of the ternary compound