Small and Medium-sized Enterprises (SMEs) are considered the backbone of global economy, but they often face cyberthreats which threaten their financial stability and operational continuity. This work aims to offer a ...Small and Medium-sized Enterprises (SMEs) are considered the backbone of global economy, but they often face cyberthreats which threaten their financial stability and operational continuity. This work aims to offer a proactive cybersecurity approach to safeguard SMEs against these threats. Furthermore, to mitigate these risks, we propose a comprehensive framework of practical and scalable cybersecurity measurements/protocols specifically for SMEs. These measures encompass a spectrum of solutions, from technological fortifications to employee training initiatives and regulatory compliance strategies, in an effort to cultivate resilience and awareness among SMEs. Additionally, we introduce a specially designed a Java-based questionnaire software tool in order to provide an initial framework for essential cybersecurity measures and evaluation for SMEs. This tool covers crucial topics such as social engineering and phishing attempts, implementing antimalware and ransomware defense mechanisms, secure data management and backup strategies and methods for preventing insider threats. By incorporating globally recognized frameworks and standards like ISO/IEC 27001 and NIST guidelines, this questionnaire offers a roadmap for establishing and enhancing cybersecurity measures.展开更多
Objective(s): The cutting-edge assessment of voice disorders includes objective and subjective methods in the daily clinical practice. The latter assessment is usually performed through the administration of self-repo...Objective(s): The cutting-edge assessment of voice disorders includes objective and subjective methods in the daily clinical practice. The latter assessment is usually performed through the administration of self-reported questionnaires. Voice Handicap Index (VHI) is one of the most widely used tools both in clinical practice and in research level. This tool-questionnaire was employed in this research along with the Voice Evaluation Template (VEF). In turn, the aim of this study was to analyse and produce the cut-off points of VHI for voice-disordered patients in Greece by using Receiver Operating Characteristic Curves (ROC Curves). Methods: Sixty-three participants (40 non-dysphonic and 23 with different types of dysphonia) were classified by ENT (Ear, Nose, and Throat) doctors and SLPs (Speech-Language Pathologists). The Hellenic VHI along with the translated Greek version of the VEF was administered to the subjects of this research. Results: The voice-disordered subjects exhibited higher overall VHI scores (in total and in its 3 subdomains) compared to the control group. Statistical significant differences were found between dysphonic and non-dysphonic participants for all VHI’s construct domains. The cut-off point of VHI total score was estimated at the value of 14.50 (sensitivity: 0.870, 1-specificity: 0.000). Moreover, the cut-off points of the three subdomains were computed as 7.50 for functional (sensitivity: 0.783, 1-specificity: 0.000), 8.50 for physical (sensitivity: 0.739, 1-specificity: 0.000) and 8.50 for emotional domain (sensitivity: 0.783, 1-specificity: 0.050). Conclusion: The preliminary statistical and ROC data analysis of VHI concluded that by using this type of assessment method, populations with or without voice disorders (in Greece) can be distinguished. Albeit this tool is a non-interventional method it could consequently offer an adequate screening and monitoring capability.展开更多
The necessity of lowering the mean power consumption of various facilities, due to the lack of their enormous future energy needs, led to an ongoing advance of various technologies. These technologies have been orient...The necessity of lowering the mean power consumption of various facilities, due to the lack of their enormous future energy needs, led to an ongoing advance of various technologies. These technologies have been oriented towards the concept of a Reduced Ecological Footprint. Massive structures (such as building complexes and hospitals) have been redesigned and upgraded;many interior designs have been dramatically altered while new electronic devices are constantly being produced in order to revolutionize a long term perspective towards a “Green Planet” while they exhibit astonishing signal processing. Consequently, an enormous technology already exists which needs to be properly combined to a proposed methodology and to new ideas relevant to systems’ administration through automatic wireless control. This paper intends to reduce the gap between design and realization of the aforementioned research. Consequently, the primary contribution of this research is the proposal of a complete design protocol with minimized defects relevant to Reduced Ecological Footprints of Facilities (REFF) along with its beneficial advantages relevant to providing a healthy and productive work environment. This protocol consists of four main parts which are 1) the main key points-guidelines, 2) its objectives, 3) the know-how methodology for implementation in existing installations and 4) the description of the imminent benefits in workforce/human resources.展开更多
Objective(s): Laryngeal inflammations lead to voice disorders. Medical conditions such as chronic laryngitis, gastroesophageal reflux, laryngopharyngeal reflux, Reinke edema and/or vocal folds hemorrhage, result in di...Objective(s): Laryngeal inflammations lead to voice disorders. Medical conditions such as chronic laryngitis, gastroesophageal reflux, laryngopharyngeal reflux, Reinke edema and/or vocal folds hemorrhage, result in diverse symptoms including chronic cough, throat cleaning and dysphonia (e.g. hoarseness). In turn, the dysphonic symptoms can be evaluated via subjective and objective procedures. The objective procedures usually include self-perceived questionnaires like the Voice Handicap Index (VHI). Studies reported that VHI can distinguish objectively dysphonic and non-dysphonic populations using the cut-off points of Receiver Operating Characteristic Curves. The purpose of this study was to calculate the cut-off points for individuals exhibiting voice symptoms which had been developed from laryngeal inflammatory diseases in Greece. Methods: One hundred and twelve participants (90 non-dysphonic and 22 dysphonic) filled in the Hellenic Voice Handicap Index (VHI) and the Greek translated version of Voice Evaluation Template (VEF) were administrated. All subjects were evaluated by an Otolaryngologist and a Speech-Language Pathologist. Results: The group with voice disorders exhibited higher VHI scores (in total and in its 3 subdomains) compared to non-dysphonic subgroup. Statistical significant differences were found for all VHI’s total cut-off point of 19.50 (sensitivity: 0.882, 1-specificity: 0.011) and for its three subdomains [functional 6.50 (sensitivity = 0.636, and 1-specificity = 0.022);physical 9.50 (sensitivity = 0.636, and 1-specificity = 0.000);emotional 6.50 (sensitivity = 0.455, and 1-specificity = 0.133)]. Conclusion: The preliminary results showed that VHI could discriminate individuals having voice disorders from laryngeal inflammations. The Voice Handicap Index can be used as a primary health care tool and a self-monitoring procedure in acute and sub-acute phases of the laryngeal inflammation.展开更多
Encouraged by next-generation networks and autonomous vehicle systems,vehicular networks must employ advanced technologies to guarantee personal safety,reduce traffic accidents and ease traffic jams.By leveraging the ...Encouraged by next-generation networks and autonomous vehicle systems,vehicular networks must employ advanced technologies to guarantee personal safety,reduce traffic accidents and ease traffic jams.By leveraging the computing ability at the network edge,multi-access edge computing(MEC)is a promising technique to tackle such challenges.Compared to traditional full offloading,partial offloading offers more flexibility in the perspective of application as well as deployment of such systems.Hence,in this paper,we investigate the application of partial computing offloading in-vehicle networks.In particular,by analyzing the structure of many emerging applications,e.g.,AR and online games,we convert the application structure into a sequential multi-component model.Focusing on shortening the application execution delay,we extend the optimization problem from the single-vehicle computing offloading(SVCOP)scenario to the multi-vehicle computing offloading(MVCOP)by taking multiple constraints into account.A deep reinforcement learning(DRL)based algorithm is proposed as a solution to this problem.Various performance evaluation results have shown that the proposed algorithm achieves superior performance as compared to existing offloading mechanisms in deducing application execution delay.展开更多
In the rapidly evolving landscape of natural language processing(NLP)and sentiment analysis,improving the accuracy and efficiency of sentiment classification models is crucial.This paper investigates the performance o...In the rapidly evolving landscape of natural language processing(NLP)and sentiment analysis,improving the accuracy and efficiency of sentiment classification models is crucial.This paper investigates the performance of two advanced models,the Large Language Model(LLM)LLaMA model and NLP BERT model,in the context of airline review sentiment analysis.Through fine-tuning,domain adaptation,and the application of few-shot learning,the study addresses the subtleties of sentiment expressions in airline-related text data.Employing predictive modeling and comparative analysis,the research evaluates the effectiveness of Large Language Model Meta AI(LLaMA)and Bidirectional Encoder Representations from Transformers(BERT)in capturing sentiment intricacies.Fine-tuning,including domain adaptation,enhances the models'performance in sentiment classification tasks.Additionally,the study explores the potential of few-shot learning to improve model generalization using minimal annotated data for targeted sentiment analysis.By conducting experiments on a diverse airline review dataset,the research quantifies the impact of fine-tuning,domain adaptation,and few-shot learning on model performance,providing valuable insights for industries aiming to predict recommendations and enhance customer satisfaction through a deeper understanding of sentiment in user-generated content(UGC).This research contributes to refining sentiment analysis models,ultimately fostering improved customer satisfaction in the airline industry.展开更多
We consider the inverse electromagnetic scattering problem of determining the shape of a perfectly conducting core inside a penetrable chiral body. We prove the well-posedness of the corresponding direct scattering pr...We consider the inverse electromagnetic scattering problem of determining the shape of a perfectly conducting core inside a penetrable chiral body. We prove the well-posedness of the corresponding direct scattering problem by the variational method. We focus on a uniqueness result for the inverse scattering problem that is under what conditions an obstacle can be identified by the knowledge of the electric far-field pattern corresponding to all time-harmonic incident planes waves with a fixed wave number. To this end, we establish a chiral mixed reciprocity relation that connects the electric far-field pattern of a spherical wave with the scattered field of a plane wave.展开更多
The demanding objectives for the future sixth generation(6G)of wireless communication networks have spurred recent research efforts on novel materials and radio-frequency front-end architectures for wireless connectiv...The demanding objectives for the future sixth generation(6G)of wireless communication networks have spurred recent research efforts on novel materials and radio-frequency front-end architectures for wireless connectivity,as well as revolutionary communication and computing paradigms.Among the pioneering candidate technologies for 6G belong the reconfigurable intelligent surfaces(RISs),which are artificial planar structures with integrated electronic circuits that can be programmed to manipulate the incoming electromagnetic field in a wide variety of functionalities.Incorporating RISs in wireless networks have been recently advocated as a revolutionary means to transform any wireless signal propagation environment to a dynamically programmable one,intended for various networking objectives,such as coverage extension and capacity boosting,spatiotemporal focusing with benefits in energy efficiency and secrecy,and low electromagnetic field exposure.Motivated by the recent increasing interests in the field of RISs and the consequent pioneering concept of the RIS-enabled smart wireless environments,in this paper,we overview and taxonomize the latest advances in RIS hardware architectures as well as the most recent developments in the modeling of RIS unit elements and RIS-empowered wireless signal propagation.We also present a thorough overview of the channel estimation approaches for RIS-empowered communications systems,which constitute a prerequisite step for the optimized incorporation of RISs in future wireless networks.Finally,we discuss the relevance of the RIS technology in the latest wireless communication standards,and highlight the current and future standardization activities for the RIS technology and the consequent RIS-empowered wireless networking approaches.展开更多
We consider the scattering of time-harmonic plane waves by an infinitely long penetrable chiral cylinder. The electromagnetic scattering problem is reduced to a transmission problem for a system of two-dimensional Hel...We consider the scattering of time-harmonic plane waves by an infinitely long penetrable chiral cylinder. The electromagnetic scattering problem is reduced to a transmission problem for a system of two-dimensional Helmholtz equations. We prove the classical reciprocity principle, a general scattering theorem and an optical theorem in R<sup>2</sup>. Using Herglotz wave functions we define the corresponding far field operator. Applying the general scattering theorem useful relations are proved for the reconstruction of the scatterer. We also prove that for real chirality measure of the penetrable scatterer the far field operator has a countable number of eigenvalues which lie on a circle.展开更多
In this paper,we study the advantages of cooperation in broadcasting systems from a geosynchronous earth orbit(GEO)satellite to mobile terminals(MTs),achieved through a terrestrial complementary ground station(CGS) wi...In this paper,we study the advantages of cooperation in broadcasting systems from a geosynchronous earth orbit(GEO)satellite to mobile terminals(MTs),achieved through a terrestrial complementary ground station(CGS) with fixed installment,which acts as a relay.Moreover and in the context of the digital video broadcasting-satellite-to-handheld(DVB-SH) standard,the performance improvements offered by the rotated constellations method are investigated,where prior transmission,a phase rotation of the transmitted symbols by a fixed angle is applied followed by a random component interleaver.Turbo codes with soft decision decoding and appropriate random channel interleavers are also considered.We present analytical expressions for the bit log-likelihood ratios(LLRs)that are needed for soft decision decoding at the MT turbo decoder,while the code combining technique is adapted to improve the end-to-end(E2E) performance.Then,we obtain through extensive computer simulations the average bit error probability(ABEP) of quadrature phase-shift keying(QPSK) signals received over pure land-mobile satellite(LMS)and pure CGS links for coding rates 1/3 and6/7.Moreover,the optimal rotation angles are obtained for both links.E2 E ABEP results are then presented assuming cooperation between GEO and CGS,while the power allocation issue is investigated under fixed total transmission power.Our performance evaluation results show that by using the constellation rotation technique,a performance gain can be achieved for high coding rates.展开更多
A comprehensive study of an all-optical chaotic communication system,including experimental realization,real-world testing and performance characterization through bit-error-rate analysis,is presented.Pseudorandom bit...A comprehensive study of an all-optical chaotic communication system,including experimental realization,real-world testing and performance characterization through bit-error-rate analysis,is presented.Pseudorandom bit sequences that are effectively encrypted in a broadband carrier produced by a chaotic emitter and sent for transmission are recovered at the receiver side.Bit-error-rate(BER) values as low as 10-7 for 1 Gb/s data rate have been achieved.Different data code lengths and bit-rates at the Gb/s region have been tested.The application of optical transmission using 100km fiber spools in an in-situ experiment and 120km in an installed optical network showed that transmission effects do not act as a considerably deteriorating factor in the final performance of chaos-based optical communication systems.展开更多
A time-harmonic plane acoustic wave is scattered by a piecewise homogeneous obstacle with a penetrable or impenetrable core. We construct in the close form an integral representation for the far field pattern in which...A time-harmonic plane acoustic wave is scattered by a piecewise homogeneous obstacle with a penetrable or impenetrable core. We construct in the close form an integral representation for the far field pattern in which we have incorporated the physical and geometrical characteristics of the scatterer. Through this representation, we obtain the far field pattern for this scatterer. We prove scattering relations between the far field patterns of two scattering problems due to two distinct incident waves on the same scatterer. In particular, we prove reciprocity and general scattering theorems. The optical theorem, connecting the total power that the scatterer extracts from the incident plane wave either by radiation or by absorption with the corresponding far field pattern of an incident plane wave, is recovered as a corollary of the general scattering theorem. Moreover, if we consider incident waves to be both a plane and a spherical, we derive a mixed reciprocity theorem. We define the corresponding far field operators and using these relations, we prove some properties that can be used for solving inverse scattering problems.展开更多
The Agriculture business domain,as a vital part of the overall supply chain,is expected to highly evolve in the upcoming years via the developments,which are taking place on the side of the Future Internet.This paper ...The Agriculture business domain,as a vital part of the overall supply chain,is expected to highly evolve in the upcoming years via the developments,which are taking place on the side of the Future Internet.This paper presents a novel Business-to-Business collaboration platform from the agri-food sector perspective,which aims to facilitate the collaboration of numerous stakeholders belonging to associated business domains,in an effective and flexible manner.The contemporary B2B collaboration schemes already place the requirements for swift deployment of cloud applications,capable of both integrating diverse legacy systems,as well as developing in a rapid way new services and systems,which will be able to instantly communicate and provide complete,"farm-to-fork"solutions for farmers,agrifood and logistics service providers,ICT companies,end-product producers,etc.To this end,this conceptual paper describes how these requirements are addressed via the FIspace B2B platform,focusing on the Greenhouse Management&Control scenarios.展开更多
For our KDP crystal orientation, various tbermo-optic （TO） and relevant temperature-dependence param- eters are defined, presented, and studied in the framework of a transverse and a longitudinal electro-optic （EO...For our KDP crystal orientation, various tbermo-optic （TO） and relevant temperature-dependence param- eters are defined, presented, and studied in the framework of a transverse and a longitudinal electro-optic （EO） modulation systems. This study is based on the concept of the so-called opto-electrical bias （~） ap- plied to the system. For both of the above EO-modulation systems, a set of original equations is extracted and investigated with regard to each of the more important TO or temperature coefficients. Using these equations, for these parameters the role of the transverse configuration is examined in comparison with its corresponding longitudinal configuration. A comparison is done with other orientation of the same KDP crystal.展开更多
The fifth generation(5G)of wireless networks features three core use cases,namely ultra-reliable and low latency communications(URLLC),massive machine type communications(mMTC),and enhanced mobile broadband(eMBB).Thes...The fifth generation(5G)of wireless networks features three core use cases,namely ultra-reliable and low latency communications(URLLC),massive machine type communications(mMTC),and enhanced mobile broadband(eMBB).These use cases co-exist in many practical scenarios and compete for the same set of time and frequency resources,resulting in a natural trade-off in their performance.In this paper,a network supporting both URLLC and eMBB modes of operation is studied.To guarantee the ultra low latency requirement of URLLC,a dynamic resource allocation scheme indicated by a two-dimensional bitmap is proposed.This approach is capable to achieve finer granularity as well as lower false cancellation rate compared to the state-of-the-art methods.A novel power control and indication method is also proposed to dynamically provide different power control parameters to the user equipment(UE),while guaranteeing the reliability requirement of URLLC and minimizing the impact to eMBB.In addition,we devise a dynamic selection mechanism(DSM)to accommodate diverse scenarios,which is empowered with load prediction to become more intelligent.Our extensive system-level simulation results for eMBB-URLLC co-existence scenarios showcase that the perceived throughput of eMBB UEs is increased by 45.3%,while about 13.3% more UEs are enjoying URLLC services with at most 84% transmit power savings compared to the state-of-the-art methods.展开更多
With the rapid development of photogrammetry,computer vision and three-dimensional(3D)modeling technologies,it is possible to efficiently construct detailed 3D urban models.Accordingly,large corpora of 3D models,such ...With the rapid development of photogrammetry,computer vision and three-dimensional(3D)modeling technologies,it is possible to efficiently construct detailed 3D urban models.Accordingly,large corpora of 3D models,such as the Google 3D Warehouse,are now becoming freely available on the web.How to find the proper 3D urban models is a challenging research issue.In this paper,we join shape descriptors and color descriptors for 3D urban model retrieval.The query objects are localized and segmented automatically from the input images by using a new selective search voting algorithm.Through combining the normalization with the light field descriptor,the Horizontal Light Descriptor is introduced to measure the shape similarity among the normalized urban models.The color descriptors are used to represent the color information of the urban models.The two types of descriptors are joined to search 3D urban models similar to the query objects.Experimental results have shown the effectiveness of our approach.展开更多
Reconfigurable intelligent surfaces(RISs)are lately being attractive for their great potential in future sixth generation wireless communications(6G),which is attributed to their affordable energy consumption and easy...Reconfigurable intelligent surfaces(RISs)are lately being attractive for their great potential in future sixth generation wireless communications(6G),which is attributed to their affordable energy consumption and easy integration.However,the large numbers of low-cost reflecting elements comprising RISs impose challenges for channel acquisition in various RIS-based wireless applications,such as RIS-enhanced orthogonal frequency-division multiplexing and multi-user multipleinput multiple-output systems.In this article,we first overview the state-of-the-art RIS hardware architectures designed to assist channel estimation for RIS-empowered wireless communication systems.We also overview existing channel estimation approaches,which are categorized into model-based and model-free techniques,and discuss their advantages and limitations depending on the RIS deployment.Design challenges with RIS-empowered systems in terms of hardware and other parameter limitations are presented,together with future research directions for channel estimation in RIS-based wireless systems,such as RISs with extremely large numbers of elements,multi-hop communications with RISs,and frequency division duplexing for high mobility systems.展开更多
The Network Makeup Artist(NORMA) is a web tool for interactive network annotation visualization and topological analysis, able to handle multiple networks and annotations simultaneously. Precalculated annotations(e.g....The Network Makeup Artist(NORMA) is a web tool for interactive network annotation visualization and topological analysis, able to handle multiple networks and annotations simultaneously. Precalculated annotations(e.g., Gene Ontology, Pathway enrichment, community detection,or clustering results) can be uploaded and visualized in a network, either as colored pie-chart nodes or as color-filled areas in a 2D/3D Venn-diagram-like style. In the case where no annotation exists,algorithms for automated community detection are offered. Users can adjust the network views using standard layout algorithms or allow NORMA to slightly modify them for visually better group separation. Once a network view is set, users can interactively select and highlight any group of interest in order to generate publication-ready figures. Briefy, with NORMA, users can encode three types of information simultaneously. These are 1) the network, 2) the communities or annotations of interest, and 3) node categories or expression values. Finally, NORMA offers basic topological analysis and direct topological comparison across any of the selected networks. NORMA service is available at http://norma.pavlopouloslab.info, whereas the code is available at https://github.com/Pavlopoulos Lab/NORMA.展开更多
Nowadays,an increasing number of blockchain architectures provide well-promising protocols for pseudonymous online payments via proposed cryptocurrencies.Most of them suffer from a number of extensibility and scalabil...Nowadays,an increasing number of blockchain architectures provide well-promising protocols for pseudonymous online payments via proposed cryptocurrencies.Most of them suffer from a number of extensibility and scalability issues,as their capacity regarding the number of transactions they are capable of processing per second is limited.Security is also a challenge for this kind of architectures.This paper presents the design and implementation of the Adrestus system,a blockchain-based transaction system with a novel consensus mechanism that is able to tolerate Byzantine faults and is designed to scale without compromising system security.One of the main components of the Adrestus design is a consistent hashing mechanism for the efficient assignment of transactions on parallel regions,called zones,and for solving load balancing problems.We claim that the Adrestus blockchain system scales linearly without compromising system security and achieves its goals without introducing the unnecessary overhead and by eliminating energy and computational waste.Preliminary theoretical simulations and results reflect that Adrestus exceeds the average throughput of the most well-known cryptocurrencies like Bitcoin,and thus,it achieves a higher performance.In this paper,we present this proposed approach along with simulation results and examine the conditions for the proposed fault-tolerant system to meet safety and liveness.展开更多
文摘Small and Medium-sized Enterprises (SMEs) are considered the backbone of global economy, but they often face cyberthreats which threaten their financial stability and operational continuity. This work aims to offer a proactive cybersecurity approach to safeguard SMEs against these threats. Furthermore, to mitigate these risks, we propose a comprehensive framework of practical and scalable cybersecurity measurements/protocols specifically for SMEs. These measures encompass a spectrum of solutions, from technological fortifications to employee training initiatives and regulatory compliance strategies, in an effort to cultivate resilience and awareness among SMEs. Additionally, we introduce a specially designed a Java-based questionnaire software tool in order to provide an initial framework for essential cybersecurity measures and evaluation for SMEs. This tool covers crucial topics such as social engineering and phishing attempts, implementing antimalware and ransomware defense mechanisms, secure data management and backup strategies and methods for preventing insider threats. By incorporating globally recognized frameworks and standards like ISO/IEC 27001 and NIST guidelines, this questionnaire offers a roadmap for establishing and enhancing cybersecurity measures.
文摘Objective(s): The cutting-edge assessment of voice disorders includes objective and subjective methods in the daily clinical practice. The latter assessment is usually performed through the administration of self-reported questionnaires. Voice Handicap Index (VHI) is one of the most widely used tools both in clinical practice and in research level. This tool-questionnaire was employed in this research along with the Voice Evaluation Template (VEF). In turn, the aim of this study was to analyse and produce the cut-off points of VHI for voice-disordered patients in Greece by using Receiver Operating Characteristic Curves (ROC Curves). Methods: Sixty-three participants (40 non-dysphonic and 23 with different types of dysphonia) were classified by ENT (Ear, Nose, and Throat) doctors and SLPs (Speech-Language Pathologists). The Hellenic VHI along with the translated Greek version of the VEF was administered to the subjects of this research. Results: The voice-disordered subjects exhibited higher overall VHI scores (in total and in its 3 subdomains) compared to the control group. Statistical significant differences were found between dysphonic and non-dysphonic participants for all VHI’s construct domains. The cut-off point of VHI total score was estimated at the value of 14.50 (sensitivity: 0.870, 1-specificity: 0.000). Moreover, the cut-off points of the three subdomains were computed as 7.50 for functional (sensitivity: 0.783, 1-specificity: 0.000), 8.50 for physical (sensitivity: 0.739, 1-specificity: 0.000) and 8.50 for emotional domain (sensitivity: 0.783, 1-specificity: 0.050). Conclusion: The preliminary statistical and ROC data analysis of VHI concluded that by using this type of assessment method, populations with or without voice disorders (in Greece) can be distinguished. Albeit this tool is a non-interventional method it could consequently offer an adequate screening and monitoring capability.
文摘The necessity of lowering the mean power consumption of various facilities, due to the lack of their enormous future energy needs, led to an ongoing advance of various technologies. These technologies have been oriented towards the concept of a Reduced Ecological Footprint. Massive structures (such as building complexes and hospitals) have been redesigned and upgraded;many interior designs have been dramatically altered while new electronic devices are constantly being produced in order to revolutionize a long term perspective towards a “Green Planet” while they exhibit astonishing signal processing. Consequently, an enormous technology already exists which needs to be properly combined to a proposed methodology and to new ideas relevant to systems’ administration through automatic wireless control. This paper intends to reduce the gap between design and realization of the aforementioned research. Consequently, the primary contribution of this research is the proposal of a complete design protocol with minimized defects relevant to Reduced Ecological Footprints of Facilities (REFF) along with its beneficial advantages relevant to providing a healthy and productive work environment. This protocol consists of four main parts which are 1) the main key points-guidelines, 2) its objectives, 3) the know-how methodology for implementation in existing installations and 4) the description of the imminent benefits in workforce/human resources.
文摘Objective(s): Laryngeal inflammations lead to voice disorders. Medical conditions such as chronic laryngitis, gastroesophageal reflux, laryngopharyngeal reflux, Reinke edema and/or vocal folds hemorrhage, result in diverse symptoms including chronic cough, throat cleaning and dysphonia (e.g. hoarseness). In turn, the dysphonic symptoms can be evaluated via subjective and objective procedures. The objective procedures usually include self-perceived questionnaires like the Voice Handicap Index (VHI). Studies reported that VHI can distinguish objectively dysphonic and non-dysphonic populations using the cut-off points of Receiver Operating Characteristic Curves. The purpose of this study was to calculate the cut-off points for individuals exhibiting voice symptoms which had been developed from laryngeal inflammatory diseases in Greece. Methods: One hundred and twelve participants (90 non-dysphonic and 22 dysphonic) filled in the Hellenic Voice Handicap Index (VHI) and the Greek translated version of Voice Evaluation Template (VEF) were administrated. All subjects were evaluated by an Otolaryngologist and a Speech-Language Pathologist. Results: The group with voice disorders exhibited higher VHI scores (in total and in its 3 subdomains) compared to non-dysphonic subgroup. Statistical significant differences were found for all VHI’s total cut-off point of 19.50 (sensitivity: 0.882, 1-specificity: 0.011) and for its three subdomains [functional 6.50 (sensitivity = 0.636, and 1-specificity = 0.022);physical 9.50 (sensitivity = 0.636, and 1-specificity = 0.000);emotional 6.50 (sensitivity = 0.455, and 1-specificity = 0.133)]. Conclusion: The preliminary results showed that VHI could discriminate individuals having voice disorders from laryngeal inflammations. The Voice Handicap Index can be used as a primary health care tool and a self-monitoring procedure in acute and sub-acute phases of the laryngeal inflammation.
基金the National Natural Science Foundation of China(NSFC)(Grant No.61671072).
文摘Encouraged by next-generation networks and autonomous vehicle systems,vehicular networks must employ advanced technologies to guarantee personal safety,reduce traffic accidents and ease traffic jams.By leveraging the computing ability at the network edge,multi-access edge computing(MEC)is a promising technique to tackle such challenges.Compared to traditional full offloading,partial offloading offers more flexibility in the perspective of application as well as deployment of such systems.Hence,in this paper,we investigate the application of partial computing offloading in-vehicle networks.In particular,by analyzing the structure of many emerging applications,e.g.,AR and online games,we convert the application structure into a sequential multi-component model.Focusing on shortening the application execution delay,we extend the optimization problem from the single-vehicle computing offloading(SVCOP)scenario to the multi-vehicle computing offloading(MVCOP)by taking multiple constraints into account.A deep reinforcement learning(DRL)based algorithm is proposed as a solution to this problem.Various performance evaluation results have shown that the proposed algorithm achieves superior performance as compared to existing offloading mechanisms in deducing application execution delay.
文摘In the rapidly evolving landscape of natural language processing(NLP)and sentiment analysis,improving the accuracy and efficiency of sentiment classification models is crucial.This paper investigates the performance of two advanced models,the Large Language Model(LLM)LLaMA model and NLP BERT model,in the context of airline review sentiment analysis.Through fine-tuning,domain adaptation,and the application of few-shot learning,the study addresses the subtleties of sentiment expressions in airline-related text data.Employing predictive modeling and comparative analysis,the research evaluates the effectiveness of Large Language Model Meta AI(LLaMA)and Bidirectional Encoder Representations from Transformers(BERT)in capturing sentiment intricacies.Fine-tuning,including domain adaptation,enhances the models'performance in sentiment classification tasks.Additionally,the study explores the potential of few-shot learning to improve model generalization using minimal annotated data for targeted sentiment analysis.By conducting experiments on a diverse airline review dataset,the research quantifies the impact of fine-tuning,domain adaptation,and few-shot learning on model performance,providing valuable insights for industries aiming to predict recommendations and enhance customer satisfaction through a deeper understanding of sentiment in user-generated content(UGC).This research contributes to refining sentiment analysis models,ultimately fostering improved customer satisfaction in the airline industry.
文摘We consider the inverse electromagnetic scattering problem of determining the shape of a perfectly conducting core inside a penetrable chiral body. We prove the well-posedness of the corresponding direct scattering problem by the variational method. We focus on a uniqueness result for the inverse scattering problem that is under what conditions an obstacle can be identified by the knowledge of the electric far-field pattern corresponding to all time-harmonic incident planes waves with a fixed wave number. To this end, we establish a chiral mixed reciprocity relation that connects the electric far-field pattern of a spherical wave with the scattered field of a plane wave.
基金supported by the EU H2020 Industrial Leadership Project(No.101017011)the Scientific and Technological Research Council of Turkey(TUBITAK)(No.120E401).
文摘The demanding objectives for the future sixth generation(6G)of wireless communication networks have spurred recent research efforts on novel materials and radio-frequency front-end architectures for wireless connectivity,as well as revolutionary communication and computing paradigms.Among the pioneering candidate technologies for 6G belong the reconfigurable intelligent surfaces(RISs),which are artificial planar structures with integrated electronic circuits that can be programmed to manipulate the incoming electromagnetic field in a wide variety of functionalities.Incorporating RISs in wireless networks have been recently advocated as a revolutionary means to transform any wireless signal propagation environment to a dynamically programmable one,intended for various networking objectives,such as coverage extension and capacity boosting,spatiotemporal focusing with benefits in energy efficiency and secrecy,and low electromagnetic field exposure.Motivated by the recent increasing interests in the field of RISs and the consequent pioneering concept of the RIS-enabled smart wireless environments,in this paper,we overview and taxonomize the latest advances in RIS hardware architectures as well as the most recent developments in the modeling of RIS unit elements and RIS-empowered wireless signal propagation.We also present a thorough overview of the channel estimation approaches for RIS-empowered communications systems,which constitute a prerequisite step for the optimized incorporation of RISs in future wireless networks.Finally,we discuss the relevance of the RIS technology in the latest wireless communication standards,and highlight the current and future standardization activities for the RIS technology and the consequent RIS-empowered wireless networking approaches.
文摘We consider the scattering of time-harmonic plane waves by an infinitely long penetrable chiral cylinder. The electromagnetic scattering problem is reduced to a transmission problem for a system of two-dimensional Helmholtz equations. We prove the classical reciprocity principle, a general scattering theorem and an optical theorem in R<sup>2</sup>. Using Herglotz wave functions we define the corresponding far field operator. Applying the general scattering theorem useful relations are proved for the reconstruction of the scatterer. We also prove that for real chirality measure of the penetrable scatterer the far field operator has a countable number of eigenvalues which lie on a circle.
基金Support to the SatNEx-Ⅲ Network of Experts (SatNEx-Ⅲ) CoO2,2011-2012
文摘In this paper,we study the advantages of cooperation in broadcasting systems from a geosynchronous earth orbit(GEO)satellite to mobile terminals(MTs),achieved through a terrestrial complementary ground station(CGS) with fixed installment,which acts as a relay.Moreover and in the context of the digital video broadcasting-satellite-to-handheld(DVB-SH) standard,the performance improvements offered by the rotated constellations method are investigated,where prior transmission,a phase rotation of the transmitted symbols by a fixed angle is applied followed by a random component interleaver.Turbo codes with soft decision decoding and appropriate random channel interleavers are also considered.We present analytical expressions for the bit log-likelihood ratios(LLRs)that are needed for soft decision decoding at the MT turbo decoder,while the code combining technique is adapted to improve the end-to-end(E2E) performance.Then,we obtain through extensive computer simulations the average bit error probability(ABEP) of quadrature phase-shift keying(QPSK) signals received over pure land-mobile satellite(LMS)and pure CGS links for coding rates 1/3 and6/7.Moreover,the optimal rotation angles are obtained for both links.E2 E ABEP results are then presented assuming cooperation between GEO and CGS,while the power allocation issue is investigated under fixed total transmission power.Our performance evaluation results show that by using the constellation rotation technique,a performance gain can be achieved for high coding rates.
文摘A comprehensive study of an all-optical chaotic communication system,including experimental realization,real-world testing and performance characterization through bit-error-rate analysis,is presented.Pseudorandom bit sequences that are effectively encrypted in a broadband carrier produced by a chaotic emitter and sent for transmission are recovered at the receiver side.Bit-error-rate(BER) values as low as 10-7 for 1 Gb/s data rate have been achieved.Different data code lengths and bit-rates at the Gb/s region have been tested.The application of optical transmission using 100km fiber spools in an in-situ experiment and 120km in an installed optical network showed that transmission effects do not act as a considerably deteriorating factor in the final performance of chaos-based optical communication systems.
文摘A time-harmonic plane acoustic wave is scattered by a piecewise homogeneous obstacle with a penetrable or impenetrable core. We construct in the close form an integral representation for the far field pattern in which we have incorporated the physical and geometrical characteristics of the scatterer. Through this representation, we obtain the far field pattern for this scatterer. We prove scattering relations between the far field patterns of two scattering problems due to two distinct incident waves on the same scatterer. In particular, we prove reciprocity and general scattering theorems. The optical theorem, connecting the total power that the scatterer extracts from the incident plane wave either by radiation or by absorption with the corresponding far field pattern of an incident plane wave, is recovered as a corollary of the general scattering theorem. Moreover, if we consider incident waves to be both a plane and a spherical, we derive a mixed reciprocity theorem. We define the corresponding far field operators and using these relations, we prove some properties that can be used for solving inverse scattering problems.
基金The research,leading to these results,has received funding from the European Commission’s Seventh Framework program FP7-ICT-2012 under grant agreement N°604123 also referred to as FIspace(Future Internet Business Collaboration Networks in Agri-Food,Transport and Logistics).
文摘The Agriculture business domain,as a vital part of the overall supply chain,is expected to highly evolve in the upcoming years via the developments,which are taking place on the side of the Future Internet.This paper presents a novel Business-to-Business collaboration platform from the agri-food sector perspective,which aims to facilitate the collaboration of numerous stakeholders belonging to associated business domains,in an effective and flexible manner.The contemporary B2B collaboration schemes already place the requirements for swift deployment of cloud applications,capable of both integrating diverse legacy systems,as well as developing in a rapid way new services and systems,which will be able to instantly communicate and provide complete,"farm-to-fork"solutions for farmers,agrifood and logistics service providers,ICT companies,end-product producers,etc.To this end,this conceptual paper describes how these requirements are addressed via the FIspace B2B platform,focusing on the Greenhouse Management&Control scenarios.
文摘For our KDP crystal orientation, various tbermo-optic （TO） and relevant temperature-dependence param- eters are defined, presented, and studied in the framework of a transverse and a longitudinal electro-optic （EO） modulation systems. This study is based on the concept of the so-called opto-electrical bias （~） ap- plied to the system. For both of the above EO-modulation systems, a set of original equations is extracted and investigated with regard to each of the more important TO or temperature coefficients. Using these equations, for these parameters the role of the transverse configuration is examined in comparison with its corresponding longitudinal configuration. A comparison is done with other orientation of the same KDP crystal.
文摘The fifth generation(5G)of wireless networks features three core use cases,namely ultra-reliable and low latency communications(URLLC),massive machine type communications(mMTC),and enhanced mobile broadband(eMBB).These use cases co-exist in many practical scenarios and compete for the same set of time and frequency resources,resulting in a natural trade-off in their performance.In this paper,a network supporting both URLLC and eMBB modes of operation is studied.To guarantee the ultra low latency requirement of URLLC,a dynamic resource allocation scheme indicated by a two-dimensional bitmap is proposed.This approach is capable to achieve finer granularity as well as lower false cancellation rate compared to the state-of-the-art methods.A novel power control and indication method is also proposed to dynamically provide different power control parameters to the user equipment(UE),while guaranteeing the reliability requirement of URLLC and minimizing the impact to eMBB.In addition,we devise a dynamic selection mechanism(DSM)to accommodate diverse scenarios,which is empowered with load prediction to become more intelligent.Our extensive system-level simulation results for eMBB-URLLC co-existence scenarios showcase that the perceived throughput of eMBB UEs is increased by 45.3%,while about 13.3% more UEs are enjoying URLLC services with at most 84% transmit power savings compared to the state-of-the-art methods.
基金supported by the National Natural Science Foundation of China[Grant 41371324].
文摘With the rapid development of photogrammetry,computer vision and three-dimensional(3D)modeling technologies,it is possible to efficiently construct detailed 3D urban models.Accordingly,large corpora of 3D models,such as the Google 3D Warehouse,are now becoming freely available on the web.How to find the proper 3D urban models is a challenging research issue.In this paper,we join shape descriptors and color descriptors for 3D urban model retrieval.The query objects are localized and segmented automatically from the input images by using a new selective search voting algorithm.Through combining the normalization with the light field descriptor,the Horizontal Light Descriptor is introduced to measure the shape similarity among the normalized urban models.The color descriptors are used to represent the color information of the urban models.The two types of descriptors are joined to search 3D urban models similar to the query objects.Experimental results have shown the effectiveness of our approach.
基金supported by the China National Key R&D Program(2021YFA1000500)National Natural Science Foundation of China(62101492)+4 种基金Zhejiang Provincial Natural Science Foundation of China(LR22F010002)Zhejiang University Global Partnership Fund,Zhejiang University Education Foundation Qizhen Scholar Foundation,and Fundamental Research Funds for the Central Universities(2021FZZX001-21)supported in part by the European Commission through the H2020 ARIADNE project(871464)and through the H2020 RISE-6G project(101017011)by the Agence Nationale de la Recherche(ANR)through the PEPR-5G projectThis research is supported by the Ministry of Education,Singapore,under its MOE Tier 2(Award number MOE-T2EP50220-0019).
文摘Reconfigurable intelligent surfaces(RISs)are lately being attractive for their great potential in future sixth generation wireless communications(6G),which is attributed to their affordable energy consumption and easy integration.However,the large numbers of low-cost reflecting elements comprising RISs impose challenges for channel acquisition in various RIS-based wireless applications,such as RIS-enhanced orthogonal frequency-division multiplexing and multi-user multipleinput multiple-output systems.In this article,we first overview the state-of-the-art RIS hardware architectures designed to assist channel estimation for RIS-empowered wireless communication systems.We also overview existing channel estimation approaches,which are categorized into model-based and model-free techniques,and discuss their advantages and limitations depending on the RIS deployment.Design challenges with RIS-empowered systems in terms of hardware and other parameter limitations are presented,together with future research directions for channel estimation in RIS-based wireless systems,such as RISs with extremely large numbers of elements,multi-hop communications with RISs,and frequency division duplexing for high mobility systems.
基金supported by the Operational Program Competitiveness,Entrepreneurship,Innovation,NSRF 2014-2020 (Grant No.MIS 5002562,co-financed by Greece and the European Union (European Regional Development Fund)supported by the Hellenic Foundation for Research and Innovation (HFRI) under the"First Call for HFRI Research Projects to support Faculty members and Researchers and the procurement of high-cost research equipment grant"(Grant No.1855-BOLOGNA)+2 种基金supported by the Action Strengthening Human ResourcesEducation and Lifelong Learning,2014-2020,co-funded by the European Social Fund (ESF) and the Greek State (Grant No.MIS 5000432)supported by a grant from the Stavros Niarchos Foundation to the Biomedical Sciences Research Center"Alexander Fleming",as part of the initiative of the Foundation to support the Greek research center ecosystem
文摘The Network Makeup Artist(NORMA) is a web tool for interactive network annotation visualization and topological analysis, able to handle multiple networks and annotations simultaneously. Precalculated annotations(e.g., Gene Ontology, Pathway enrichment, community detection,or clustering results) can be uploaded and visualized in a network, either as colored pie-chart nodes or as color-filled areas in a 2D/3D Venn-diagram-like style. In the case where no annotation exists,algorithms for automated community detection are offered. Users can adjust the network views using standard layout algorithms or allow NORMA to slightly modify them for visually better group separation. Once a network view is set, users can interactively select and highlight any group of interest in order to generate publication-ready figures. Briefy, with NORMA, users can encode three types of information simultaneously. These are 1) the network, 2) the communities or annotations of interest, and 3) node categories or expression values. Finally, NORMA offers basic topological analysis and direct topological comparison across any of the selected networks. NORMA service is available at http://norma.pavlopouloslab.info, whereas the code is available at https://github.com/Pavlopoulos Lab/NORMA.
文摘Nowadays,an increasing number of blockchain architectures provide well-promising protocols for pseudonymous online payments via proposed cryptocurrencies.Most of them suffer from a number of extensibility and scalability issues,as their capacity regarding the number of transactions they are capable of processing per second is limited.Security is also a challenge for this kind of architectures.This paper presents the design and implementation of the Adrestus system,a blockchain-based transaction system with a novel consensus mechanism that is able to tolerate Byzantine faults and is designed to scale without compromising system security.One of the main components of the Adrestus design is a consistent hashing mechanism for the efficient assignment of transactions on parallel regions,called zones,and for solving load balancing problems.We claim that the Adrestus blockchain system scales linearly without compromising system security and achieves its goals without introducing the unnecessary overhead and by eliminating energy and computational waste.Preliminary theoretical simulations and results reflect that Adrestus exceeds the average throughput of the most well-known cryptocurrencies like Bitcoin,and thus,it achieves a higher performance.In this paper,we present this proposed approach along with simulation results and examine the conditions for the proposed fault-tolerant system to meet safety and liveness.
