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CompactChain:an efficient stateless chain for UTXO-model blockchain

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Frontiers of Computer Science 2024年第2期18卷 167-179页

作者： B Swaroopa REDDY T Uday Kiran REDDY Department of Electrical engineering Indian Institute of Technology HyderabadHyderabadTelangana 502285India

In this work,we propose a stateless blockchain called CompactChain,which compacts the entire state of the UTXO(Unspent Transaction Output)based blockchain systems into two RSA *** first accumulator is called Transaction Output(TXO)commitment which represents the TXO *** second one is called Spent Transaction Output(STXO)commitment which represents the STXO *** this work,we discuss three algorithms:(i)To update the TXO and STXO commitments by the *** miner also provides the proofs for the correctness of the updated commitments;(ii)To prove the transaction’s validity by providing a membership witness in TXO commitment and non-membership witness against.STXO commitment for a coin being spent by a user;(iii)To update the witness for the coin that is not yet spent;The experimental results evaluate the performance of the CompactChain in terms of time taken by a miner to update the commitments and time taken by a validator to verify the commitments and validate the *** compare the performance of CompactChain with the existing state-of-the-art works on stateless *** shows a reduction in commitments update complexity and transaction witness size which inturn reduces the mempool size and propagation latency without compromising the system throughput(Transactions per second(TPS)).

关键词： stateless blockchain RSA Accumulator STXO commitment TXO commitment UTXO Non-interactive Proof of Exponentiation(NI-PoE) Transactions per second(TPS)

Millimeter wave dielectric loaded exponentially tapered slot antenna array using substrate integrated waveguide for gigabit wireless communications

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红外与毫米波学报 2015年第5期34卷 513-519页

作者： S Ramesh T Rama Rao Department of Electronics & communication engineering Valliammai Engineering College RADMIC Department of Telecommunication EngineeringSRM University

A new and upcoming application is the use of 60 GHz antennas for high date rate point-to-point connections to serve Gigabit(Gi-Fi)w ireless *** design of M illimeter w ave(M m W)antennas has to cope w ith the unadorned influences of manufacturing tolerances and losses at 60 *** this paper,the concept of Substrate Integrated Waveguide(SIW)and Exponentially Tapered Slot(ETS)antenna w ere used together to design a high gain,efficient planar dielectric loaded antenna for M m W Gi-Fi w ireless communications at 60 *** SIW is used to feed the antenna and a dielectric is utilized in front of the antenna to increase the *** dielectric loaded ETS antenna and compact SIW feed w ere fabricated on a single substrate,resulting in low cost and easy *** antenna w ith elliptical shaped dielectric loaded w as fabricated using printed circuit board *** measured gain of the single element antenna is 10.2 dB,w hile the radiation efficiency of 96.84%is obtained at 60 *** Y-junction SIW pow er divider is used to form a 1×4 array structure.M easured gain of the 1×4 array antenna is 13.3 dB,w hile the measured radiation pattern and gain are almost constant w ithin the w ide bandw idth of the antenna.

关键词： millimeter waves 60 GHz exponentially tapered slot antenna dielectric loading substrate integrated waveguide

Achievement of Bluetooth adaptive packet selection strategies based on SNR estimation

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The Journal of China Universities of Posts and telecommunications 2016年第1期23卷 8-13,48页

作者： Li Jing Chen Wanzhong Zhao Xiaohui School of telecommunication engineering Jilin University

It is necessary to estimate channel quality in order to put Bluetooth adaptive packet selection strategies into practice. However, the current Bluetooth channel quality estimation algorithms are either poor at timeliness or not applicable to systems which only support basic rate （BR） data packets （Gaussian frequency shift keying （GFSK） modulation scheme）. It is investigated to apply the channel quality estimation algorithm based on power spectrum to Bluetooth adaptive packet selection strategies in this paper. Simulation results and analysis show that the proposed channel quality estimation algorithm based on power spectrum can achieve the accuracy less than 0.2 dB in the estimation range required by Bluetooth adaptive packet selection strategies. It has simple calculation and strong timeliness. The algorithm can also be suitable for different modulation schemes of Bluetooth data packets. It provides a good precondition for the achievement of Bluetooth adaptive packet selection strategies.

关键词： computer application Bluetooth power spectrum signal-to-noise ratio estimation

Curvelet transform and contrast adaptive clip histogram equalization-based image defogging algorithm

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The Journal of China Universities of Posts and telecommunications 2018年第2期25卷 96-104页

作者： Wang Qi Wang Shigang Jia Bowen Du Hailong College of telecommunication engineering Jilin University

Due to the scattering effect of suspended particles in the atmosphere, foggy day images have reduced visibility and contrast significantly. Considering the loss of details and uneven defogging results of the contrast limited adaptive histogram equalization （CLAHE） algorithm, a curvelet transform and contrast adaptive clip histogram equalization （HE）-based foggy day image enhancement algorithm is proposed. The proposed algorithm transforms an image to the curvelet domain and enhances the image detail information via a nonlinear transformation of high frequency curvelet coefficients. After curvelet reconstruction, the contrast adaptive clip HE method is adopted to enhance the total image contrast and the foggy day image contrast and detail information. During the histogram clipping process, the clip limit value is adaptively selected based on image contrast and the sub-block image histogram variance. A comparative analysis of the foggy day image enhancement results are obtained by applying CLAHE, and some classical single image defogging algorithms and the proposed algorithm are also conducted to prove the effectiveness of the proposed algorithm with objective parameters.

关键词： defogging clip limit contrast adaptive clip HE curvelets transform

A New Approach to Multi-user Detection in DS-CDMA

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High Technology Letters 2001年第1期7卷 27-30页

作者： Tu Zhenyu 涂震宇 College of telecommunication engineering Beijing University of Posts Telecommunication

A graph model is constructed for the Multi-user Detection of DS-CDMA system. Based on it, a Hopfield-like algorithm is put forward for the implementation of optimum receiver. Compared with the Hopfield approach, it ha... 详细信息

关键词： DS-CDMA Multi-user detection Optimum receiver Hopfield neural networks Minimum Cut (MC).

A New Classifier for Facial Expression Recognition:Fuzzy Buried Markov Model

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Journal of Computer Science & Technology 2010年第3期25卷 641-650页

作者：詹永照成科扬陈亚必文传军 School of Computer Science and telecommunication engineering Jiangsu University

To overcome the disadvantage of classical recognition model that cannot perform well enough when there are some noises or lost frames in expression image sequences, a novel model called fuzzy buried Markov model （FBMM） is presented in this paper. FBMM relaxes conditional independence assumptions for classical hidden Markov model （HMM） by adding the specific cross-observation dependencies between observation elements. Compared with buried Markov model （BMM）, FBMM utilizes cloud distribution to replace probability distribution to describe state transition and observation symbol generation and adopts maximum mutual information （MMI） method to replace maximum likelihood （ML） method to estimate parameters. Theoretical justifications and experimental results verify higher recognition rate and stronger robustness of facial expression recognition for image sequences based on FBMM than those of HMM and BMM.

关键词： facial expression recognition fuzzy buried Markov model specific cross-observation dependency cloud distribution maximum mutual information

Scalable Security Solution Against.Wiretapping for Network Coding Based Priority Encoding Transmission

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Chinese Journal of Electronics 2018年第1期27卷 191-197页

作者： LIU Guangjun XIAO Song School of Information engineering Xi'an University School of telecommunication engineering Xidian University

Network coding is promising to improve the throughput and robustness of video transmission over wireless networks. To address the security issue of network coding based Priority encoding transmission(PET), a special coding design against.wiretapping is proposed with hierarchical security. The basic idea is first to randomize partial blocks of each layer and then to encode each layer with inter-layer overlapping coding. The method is characterized by quantifiable security for incremental decoding,and realizes scalability in confidentiality and video transmission, while incurring relatively low computational complexity and bandwidth overhead. A sufficient condition is also presented to design a stronger secure network coded PET system against.the known-plaintext attacks. Analysis and evaluation show that the method can be efficient as a new paradigm to secure network coded PET system in realistic applications.

关键词： Network coding Hierarchical confidentiality Priority encoding transmission(PET) Video streaming

Research and Application of Recycled Concrete Technology in Prefabricated Buildings

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Research and Application of Materials Science 2024年第1期6卷 33-36页

作者： Shanshan DENG Gang SHI Chao SHANG Fuchuan ZHOU Masabo Gasper Masiko M.Kaziana Chongqing telecommunication Polytechnic College Chongqing402247China Chongqing yuxi water conservancy and electric power survey and design inst.tute CO. LTD.Chongqing402160China Chengde Thermal Power engineering inst.llation Co. Ltd.Chengde067000China Chongqing Vocational inst.tute of engineering Chongqing402260China Undergraduate Architecture and Civil engineering Dar es Salaam Institute of Technology{DIT}Dar es Salaam11103Tanzania

The utilization of waste concrete as a raw material for recycled concrete in the domain of prefabricated components is garnering greater *** paper delineates and examines the concept,categorization,methodologies of preparation,applicable sectors,and evaluative metrics of recycled concrete technology,highlighting its prospective ***,for the successful integration of recycled concrete technology into prefabricated component applications,it is imperative to systematically enhance its physical,mechanical,and attributes,as well as its environmental ***,to foster the continued advancement of recycled concrete technology,innovative initiatives,standardization,educational programs,demonstration projects,and collaborative efforts are crucial to promote broader adoption and realize improved outcomes within the realm of prefabricated *** conclusion,recycled concrete technology is poised to play a pivotal role in prefabricated construction,offering robust support for propelling the construction industry towards a sustainable future.

关键词： recycled concrete prefabricated buildings Environmental performance assessment

Preparation and photocatalytic properties of porous C and N co-doped TiO_2 deposited on brick by a fast, one-step microwave irradiation method

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Journal of Environmental Sciences 2017年第10期29卷 24-32页

作者： Fangzhou Li Jiangshan Zhou Chun Du Wei Li Yinzhen Wang Guannan He Qinyu He South China Normal University School of Physics & Telecommunication Engineering

A one-step microwave irradiation method was used to deposit carbon and nitrogen co-doped TiO2（（C, N）-TiO2） on commercial brick（（C, N）-TiO2/brick）. The as-prepared samples were characterized by X-ray diffraction, ultraviolet–visible（UV–vis） diffuse reflectance spectroscopy, photoluminescence spectroscopy, X-ray photoelectron spectroscopy, and scanning electron microscopy（SEM）. A selective technique was also used to investigate the concentration of hydroxyl radicals during UV–vis irradiation of the Methyl Orange solution with the as-prepared samples. The C and N dopants enhanced visible light absorption and provided a longer lifetime for the photo-generated electron–hole pairs. The SEM images showed that the as-prepared sample is porous. The dark adsorption and photodegradation test for（C, N）-TiO2/brick showed good photodegradation and good recyclability. The best photodegradation rate was 94% after 2 hr. The maximum degradation rate was maintained even after the 6th cycle. The good photocatalytic properties are attributed to the enhanced visible light absorption, enhanced pollutant adsorption arising from the porous structure of the（C, N）-TiO2 thin film, and longer lifetime of the photo-generated electron–hole pairs.（C, N）-TiO2/brick should have potential commercial applications in photodegradation processes because of its low cost, good photodegradation, and excellent recyclability.

关键词： (C N)-TiO2/brick hybridization Low cost Longer lifetime Good photocatalytic properties Good recyclability