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Artigo Revisado por pares

Shanding Xu, Xiwang Cao, Guangkui Xu,

... theorem. It generalises the previous construction of optimal FHSs and FHS sets with composite lengths employing a ... specific function, their construction can produce new optimal FHSs and FHS sets that cannot be produced by ... By choosing appropriate injective functions and known optimal FHSs and FHS sets, infinitely many new optimal FHSs and FHS sets can be recursively obtained. 1 ... autocorrelation and cross-correlation of the set of FHSs. Furthermore, it is also preferred to have more FHSs to accommodate a great quantity of users. As ...

Tópico(s): Wireless Communication Networks Research

2016 - Institution of Engineering and Technology | IET Communications

Artigo Acesso aberto Revisado por pares

K. Ajay Babu, Barathram Ramkumar,

Automated recognition of fundamental heart sound segments (FHSS) from Phonocardiogram (PCG) is the preliminary step before clinical parameters extraction to detect the presence of abnormality if any. PCG acquisition systems are ... like lung sounds and speech. The recognition of FHSS is challenging in the presence of non-cardiac ... recurrent neural network (RNN) are suitable for automated FHSS. However, it will be shown that their performance ... is proposed to enhance the accuracy of automated FHSS. The conventional signal processing technique is based on ...

Tópico(s): Phonocardiography and Auscultation Techniques

2020 - Institute of Electrical and Electronics Engineers | IEEE Access

Artigo Revisado por pares

Jin-Ho Chung, Kyeongcheol Yang,

... Hamming autocorrelation is ¿ . Three new classes of optimal FHSs with respect to the Lempel-Greenberger bound are ... this paper. First, new optimal (p,M,f)-FHSs are constructed when p = Mf +1 is an ... then, a construction for optimal (kp,p,k)-FHSs is given for any odd prime p and ... 2 are odd primes. Finally, several new optimal FHSs with maximum out-of-phase Hamming autocorrelation 1 ... particular, the existence of optimal (v,N,1)-FHSs is proven for any integer N ¿ 3 and ... the existence of optimal (2N +1,N,2)-FHSs is shown for any integer N ¿ 3. These ...

Tópico(s): Advanced Wireless Communication Techniques

2010 - Institute of Electrical and Electronics Engineers | IEEE Transactions on Information Theory

Artigo Revisado por pares

Hengyun Zhang, D. Pinjala, Yogendra Joshi, Teck Neng Wong, K.C. Toh, M.K. Iyer,

... heat transfer of liquid cooled foam heat sinks (FHSs) were experimentally investigated. Eight Open-celled copper foam ... bonded onto copper base plates to form the FHSs, which were then assembled on flip chip BGA ... overall thermal resistances. For the four 60 PPI FHSs, the one with the lowest porosity of 0. ... level with the largest pressure drop. Generally the FHSs with 100 PPI had slightly lower thermal resistances ... overall performance assessment, the thermal resistances of the FHSs are plotted against the pressure drop and the ...

Tópico(s): Nanofluid Flow and Heat Transfer

2005 - Institute of Electrical and Electronics Engineers | IEEE Transactions on Components and Packaging Technologies

Artigo Revisado por pares

Cuiling Fan, Han Cai, Xiaohu Tang,

Frequency-hopping sequences (FHSs) with favorable partial Hamming correlation properties have important applications in many synchronization and multiple-access systems. Strictly optimal FHSs are those FHSs with optimal partial Hamming autocorrelation irrespective of the correlation window length. In this paper, strictly optimal FHSs are investigated from a combinatorial approach. A generic connection between strictly optimal FHSs and disjoint cyclic perfect Mendelsohn difference families is ... By virtue of this connection, new strictly optimal FHSs are generated from some disjoint CPMDFs. These strictly ...

Tópico(s): Wireless Communication Networks Research

2016 - Institute of Electrical and Electronics Engineers | IEEE Transactions on Information Theory

Artigo Revisado por pares

Feng Liu, Michael W. Marcellin, Nathan A. Goodman, Ali Bilgin,

... methods for detection of frequency-hopping spread spectrum (FHSS) signals from compressive measurements are proposed. Rapid switching ... frequency in a pseudorandom manner makes detection of FHSS signals challenging. Conventionally, FHSS detection is performed by scanning small segments of ... propose compressive detection strategies that sample the full FHSS spectrum in a compressive manner. We discuss the ... designed to maximize the mutual information between the FHSS signal and the compressive measurements. Using a mixture- ...

Tópico(s): Distributed Sensor Networks and Detection Algorithms

2016 - Institute of Electrical and Electronics Engineers | IEEE Transactions on Signal Processing

Artigo Acesso aberto Revisado por pares

Qirui Li, T.S. Amjath-Babu, Stefan Sieber, Peter Zander,

... desertification. Nevertheless, deeper investigation of farm household systems (FHSs) changes during PES projects is rather limited. It is important to understand how various FHSs evolve with the divergent resource allocation strategies aiming ... analyzed. Using principal component analysis and cluster analysis, FHSs types are identified, whereas composite indices regarding environmental, ... that investigates the multidimensional costs and benefits of FHSs types. The results show that seven distinct FHSs ...

Tópico(s): Land Use and Ecosystem Services

2018 - Wiley | Land Degradation and Development

Artigo Revisado por pares

Zhengchun Zhou, Xiaohu Tang, Xianhua Niu, Udaya Parampalli,

... partial Hamming correlation properties of frequency-hopping sequences (FHSs) are discussed. The Peng-Fan bounds on sets of FHSs are generalized to the case of partial correlation. Both individual FHSs with optimal partial autocorrelation and sets of FHSs with optimal partial correlation are presented. The former ... more new parameters compared with the known individual FHSs with optimal partial autocorrelation, while the later is ...

Tópico(s): Wireless Communication Networks Research

2011 - Institute of Electrical and Electronics Engineers | IEEE Transactions on Information Theory

Editorial Acesso aberto

Daniel B. Raemer, Alexander A. Hannenberg, Ann Mullen,

... all eventualities. The Foundation for Healthcare Simulation Safety (FHSS), has developed a 10-item "pledge" of "best ... to reduce simulation related hazards (Fig. 1). The FHSS is a not-for-profit educational organization recognized ... by individual philanthropy (http://www.healthcaresimulationsafety.org). The FHSS has been collecting anecdotes of simulation incidents that ... scope of the problem in simulation. In addition, FHSS has designed a label to be placed on ... We urge simulation programs to report incidents to FHSS for posting to the community. In addition, responsible ...

Tópico(s): Simulation-Based Education in Healthcare

2018 - Lippincott Williams & Wilkins | Simulation in Healthcare The Journal of the Society for Simulation in Healthcare

Artigo Acesso aberto Revisado por pares

Ziwei Lei, Peng Yang, Linhua Zheng,

... to detect and track frequency hopping spread spectrum (FHSS) signals due to their wideband frequencies and the ... conducting compressive sensing for blind signal processing of FHSS signals. The modulated wideband converter (MWC) is a ... However, it is difficult to adjust MWC to FHSS signals, because the support set and sparsity change ... our method can detect the channel, which contains FHSS signals in the case of a low signal- ... method leads to the successful estimation of the FHSS carrier frequency. This indicates that our method is ...

Tópico(s): Advanced Adaptive Filtering Techniques

2018 - Multidisciplinary Digital Publishing Institute | Electronics

Artigo Revisado por pares

Qi Zeng, Zhengchun Zhou, Xing Liu, Zilong Liu,

... class of no-hit-zone frequencyhopping sequences (NHZ-FHSs) in quasi-synchronous FH multiple-access (QS-FHMA) systems. Although traditional NHZ-FHSs can offer interference-free FHMA performance when the ... for time-shifts outside of the NHZ. Such FHSs are called strong NHZ-FHSs (SNHZ-FHSs) in this paper. We derive a lower bound ...

Tópico(s): Advanced Wireless Communication Techniques

2019 - IEEE Communications Society | IEEE Transactions on Communications

Artigo Revisado por pares

Yingbo Zhang, Dening Zou, Xiao‐Qiao Wang, Quansheng Wang, Ran Xu, Wei Zhang,

X10CrAlSi18 FHSS (ferritic heat-resistant stainless steel) has received a lot of attention due to its advantageous combination of ... on the high-temperature oxidation resistance of X10CrAlSi18 FHSS after oxidation at 700 and 800 °C for ... 700 °C, the oxide film of 0.77Si FHSS and 1.35Si FHSS were found to be primarily composed of Al2O3, ... structure and reduced the oxidation resistance of X10CrAlSi18 FHSS.

Tópico(s): Nuclear Materials and Properties

2021 - Elsevier BV | Surface and Coatings Technology

Artigo Revisado por pares

Yanping Bao, Jinhao Lai, Yishun Wang, Zheng Fang, SU Yong-shi, Daniel S. Alessi, Nanthi Bolan, Xiaolian Wu, Yan Zhang, Xueding Jiang, Zhi‐Hong Tu, Hailong Wang,

... In addition, the Pb(II) adsorption capabilities of FHSs biosynthesized under various FA dosages, including kinetics and ... isotherms and mechanisms of Pb onto the biosynthesized FHSs were then comprehensively characterized and modeled. Though the ... increasing FA loading, the introduction of FA into FHSs increased Pb(II) adsorption, with the highest concentration ... that the adsorption of Pb(II) onto the FHSs was correlated with the number of active sites, ... of Pb(II) in channels inside the biosynthesized FHSs, are suggested. The adsorption mechanism was attributed to ...

Tópico(s): Arsenic contamination and mitigation

2021 - Elsevier BV | Environmental Pollution

Artigo Revisado por pares

Aristides Mpitziopoulos, Damianos Gavalas,

... Our focus is on frequency hopping spread spectrum (FHSS) and direct sequence spread spectrum (DSSS), two of ... of Ares is that it uses a hybrid FHSS–DSSS approach to defend jamming attacks. We suggest the use of a specific FHSS technique in 5 GHz band with 51 frequency ... code derives from the same key used for FHSS channel generation. The pre‐eminence of our method ...

Tópico(s): Network Security and Intrusion Detection

2008 - Hindawi Publishing Corporation | Security and Communication Networks

Artigo Acesso aberto Revisado por pares

Emanuele Lopelli, Johan D. van der Tang, Arthur van Roermund,

... front-end for a frequency hopping spread spectrum (FHSS) transmitter implemented in silicon-on-anything (SOA) bipolar ... Colpitts VCO allows us to reduce the complete FHSS front-end to a single building block that ... encoding and an offset sending technique. The novel FHSS-predistortion concept has been verified by realizing a ...

Tópico(s): Full-Duplex Wireless Communications

2007 - Institute of Electrical and Electronics Engineers | IEEE Journal of Solid-State Circuits

Artigo Revisado por pares

Jaehak Chung, Kyeongcheol Yang,

... average Hamming correlation (AHC) among frequency-hopping sequences (FHSs) as well as the maximum Hamming correlation (MHC) ... with optimal AHC and (near-)optimal MHC, whose FHSs are balanced. The authors first show that any ... with optimal AHC and (near-)optimal MHC, whose FHSs are (perfectly) balanced. The authors then analyse the ... FHS sets with optimal AHC and MHC, whose FHSs are perfectly balanced.

Tópico(s): Coding theory and cryptography

2012 - Institution of Engineering and Technology | IET Communications

Artigo Revisado por pares

Han Cai, Zhengchun Zhou, Yang Yang, Xiaohu Tang,

Frequency-hopping sequences (FHSs) with favorable partial Hamming correlation properties have important applications in many synchronization and multiple-access systems. In this paper, lower bounds on the partial Hamming correlation of FHSs and FHS sets are proposed. They slightly improve ... al. and Zhou et al. A construction of FHSs and FHS sets having optimal partial Hamming correlation ... theory of generalized cyclotomy. Our construction yields optimal FHSs and FHS sets with new and flexible parameters ...

Tópico(s): graph theory and CDMA systems

2014 - Institute of Electrical and Electronics Engineers | IEEE Transactions on Information Theory

Artigo Acesso aberto Revisado por pares

Xianhua Niu, Daiyuan Peng, Zhengchun Zhou,

... paper, a new design of frequency hopping sequences (FHSs) setswith low hit zone (LHZ) is presented based ... of the new design is to use short FHSs withgood Hamming correlation together with certain appropriate shiftsequences to construct a set of long FHSs with LHZ. By the newdesign, new sets of FHSs meeting the Peng-Fan-Leebound are obtained. It ...

Tópico(s): Wireless Communication Networks Research

2013 - American Institute of Mathematical Sciences | Advances in Mathematics of Communications

Artigo Acesso aberto

Zainab T. Alisa,

... Sequence Spread Spectrum DSSS, Frequency Hopping Spread Spectrum FHSS and Orthogonal Frequency Division Multiplexing OFDM at multiple ... can use 1,2,5.5,11Mbps rates.FHSS and IR are able to operate at 1or ... OFDM technology delay is better than in DSSS.FHSS delay is less than DSSS delay.IR delay is better than FHSS and DSSS delay.In addition, for one physical ...

Tópico(s): Mobile Ad Hoc Networks

2013 - | International Journal of Computer Applications

Capítulo de livro Revisado por pares

Hocheol Shin, Kibum Choi, Youngseok Park, Jaeyeong Choi, Yongdae Kim,

... especially controllers that adopt Frequency Hopping Spread Spectrum (FHSS). In order to affect an FHSS-type controller, an attacker first has to access ... general scheme to extract the hopping sequence of FHSS-type controllers using a software-defined radio (SDR). ...

Tópico(s): Wireless Signal Modulation Classification

2016 - Springer Science+Business Media | Lecture notes in computer science

Artigo Acesso aberto Revisado por pares

Haiyu Huang, Pai‐Yen Chen, Cheng‐Hsien Hung, Ranjit Gharpurey, Deji Akinwande,

... transponder antenna sensor and frequency hopping spread spectrum (FHSS) pattern analysis, to provide a very low cost ... a confined region. The transponder first receives some FHSS signal from an interrogator, then converts such signal ... decoded through pattern analysis of the high dimensional FHSS signal strength data. A robust, zero power, absolute ... harmonic transponder sensor, metamaterial-inspired antenna sensor and FHSS pattern analysis based sensor decoding may help establishing ...

Tópico(s): Indoor and Outdoor Localization Technologies

2016 - Nature Portfolio | Scientific Reports

Artigo Acesso aberto Revisado por pares

Jingjun Bao, Lijun Ji,

Frequency hopping sequences (FHSs) with favorable partial Hamming correlation properties have important applications in many synchronization and multiple-access systems. In this paper, we investigate constructions of FHSs and FHS sets with optimal partial Hamming correlation. ... special property. By virtue of this correspondence, some FHSs and FHS sets with optimal partial Hamming correlation ... families. As a consequence, our constructions yield new FHSs and FHS sets with optimal partial Hamming correlation.

Tópico(s): Wireless Communication Networks Research

2016 - Institute of Electrical and Electronics Engineers | IEEE Transactions on Information Theory

Artigo Acesso aberto Revisado por pares

Elisavet Koutsiana, Leontios J. Hadjileontiadis, Ioanna Chouvarda, Ahsan H. Khandoker,

... technique for the detection of fetal heart sounds (fHSs). In this study, analysis of fetal phonocardiograph (fPCG) ... in the WT domain for the extraction of fHSs from the underlying noise. Its adoption in this ... of the correct location and morphology of the fHSs, reaching an overall accuracy of 89% justifying the ... paving the way for testing it in real fHSs and clearly contributing to better evaluation of the ...

Tópico(s): Music and Audio Processing

2017 - Frontiers Media | Frontiers in Bioengineering and Biotechnology

Artigo Revisado por pares

Abdulrahman Kanaa, Ahmad Zuri Sha’ameri,

Frequency hopping spread spectrum (FHSS) signals are widely implemented in both modern civilian and military applications. They are robust to channel impairments because of their ... interception. For applications that require the interception of FHSS signals, the signal parameters such as the hopping ... be accurately measured. In this paper, an accurate FHSS signal parameter estimation method is proposed based on ...

Tópico(s): Chaos control and synchronization

2017 - Elsevier BV | Physical Communication

Artigo Acesso aberto Revisado por pares

Muhammad Asad Ullah, Konstantin Mikhaylov, Hirley Alves,

Long Range-Frequency Hopping Spread Spectrum (LR-FHSS) has been recently introduced into the LoRaWAN protocol specification to increase network capacity and collision robustness, and enable direct connectivity between machine devices ... and simulation models for packet delivery over LR-FHSS from ground nodes to a LEO satellite, and ... some trade-offs between the two new LR-FHSS-based data rates for the EU region, and ...

Tópico(s): Bluetooth and Wireless Communication Technologies

2021 - Institute of Electrical and Electronics Engineers | IEEE Wireless Communications Letters

Artigo Acesso aberto

Guillem Boquet, Pere Tuset‐Peiró, Ferrán Adelantado, Thomas Watteyne, Xavier Vilajosana,

Long-range frequency hopping spread spectrum (LR-FHSS) is the new physical layer designed to address extremely long-range and large-scale communication scenarios, such as satellite IoT. At its core ... same radio link budget as LoRa. Additionally, LR-FHSS finely manages packet transmission thanks to its design ... is a reference for understanding how exactly LR-FHSS works, the performance it can offer, and its ...

Tópico(s): Energy Harvesting in Wireless Networks

2021 - Institute of Electrical and Electronics Engineers | IEEE Communications Magazine

Artigo Acesso aberto Revisado por pares

Yingbo Zhang, Dening Zou, Yunong Li, Yu Wang, Wei Zhang, Xiaoming Zhang,

... 800 and 900 °C) of 18Cr–Al–Si FHSS (ferritic heat-resistant stainless steel) for up to ... oxide films that formed on the 0.63Al FHSS and 1.06Al FHSS were composed of spinel MnCr2O4 in the outer ... inner layer. The middle layer of 0.63Al FHSS also contained a small amount of Fe2O3. The ...

Tópico(s): High Temperature Alloys and Creep

2021 - Elsevier BV | Journal of Materials Research and Technology

Artigo Revisado por pares

Yuxin Shi, Kang An, Yusheng Li,

... index modulation based frequency hopping spread spectrum (IM-FHSS) scheme. Specifically, the current available frequencies are determined ... active and idle frequencies. With such implementation, IM-FHSS can obtain the improved resistance of reactive symbol- ... the alternative spectral efficiency (SE) mode of IM-FHSS in order to meet the high SE and ... Theoretical analysis and simulation results show that IM-FHSS exhibits enhanced resistance to reactive symbol-level jamming ...

Tópico(s): Security in Wireless Sensor Networks

2021 - Institute of Electrical and Electronics Engineers | IEEE Transactions on Vehicular Technology

Artigo Revisado por pares

Peihua Li, Cuiling Fan, Sihem Mesnager, Yang Yang, Zhengchun Zhou,

... frequency hopping (FH) communication systems, frequency hopping sequences (FHSs) are crucial in determining the system's anti-jamming performance. If FHSs can ensure a wide-gap between two adjacent ... be enhanced. Therefore, it is desirable to employ FHSs with low Hamming autocorrelation, wide frequency-hopping gap, ... of our knowledge, no such infinite classes of FHSs have been reported in the literature to date. ...

Tópico(s): Advanced Wireless Communication Techniques

2021 - Institute of Electrical and Electronics Engineers | IEEE Transactions on Information Theory

Artigo Acesso aberto Revisado por pares

Muhammad Arshad, Muhammad Saeed, Atiqe Ur Rahman, Dilovan Asaad Zebari, Mazin Abed Mohammed, Alaa S. Al‐Waisy, Marwan Ali Albahar, Mohammed Thanoon,

... algebraic approach, interval-valued fuzzy hypersoft set (iv-FHSS), is employed to assess the conditions of patients ... Omicron-diagnosed patients are shortlisted and an iv-FHSS is constructed for such patients and then they are medicated. Another iv-FHSS is constructed after their first medication. Similarly, the ... FHSSs are computed with pre-medication-based iv-FHSS and the monotone pattern of distance measures are ...

Tópico(s): Rough Sets and Fuzzy Logic

2022 - Multidisciplinary Digital Publishing Institute | Bioengineering