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A Hybrid Cybersecurity Algorithm for Digital Image Transmission over Advanced Communication Channel Models

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Computers, Materials & Continua 2024年第4期79卷 201-241页

作者： Naglaa f.Soliman fatma E.fadl-Allah Walid El-Shafai Mahmoud I.Aly Maali Alabdulhafith fathi E.Abd El-Samie Department of Information Technology College of Computer and Information SciencesPrincess Nourah bint Abdulrahman UniversityP.O.Box 84428Riyadh11671Saudi Arabia Department of Electronics and Communications Faculty of EngineeringZagazig UniversityZagazig44519Egypt Security Engineering Lab Computer Science DepartmentPrince Sultan UniversityRiyadh11586Saudi Arabia Department of Electronics and Electrical Communications Engineering Faculty of Electronic EngineeringMenoufia UniversityMenouf32952Egypt

The efficient transmission of images,which plays a large role inwireless communication systems,poses a significant challenge in the growth of multimedia ***-quality images require well-tuned communication *** Single Carrier frequency Division Multiple Access(SC-fDMA)is adopted for broadband wireless communications,because of its low sensitivity to carrier frequency offsets and low Peak-to-Average Power Ratio(PAPR).Data transmission through open-channel networks requires much concentration on security,reliability,and *** data need a space away fromunauthorized access,modification,or *** requirements are to be fulfilled by digital image watermarking and *** paper ismainly concerned with secure image communication over the wireless SC-fDMA systemas an adopted communication *** introduces a robust image communication framework over SC-fDMA that comprises digital image watermarking and encryption to improve image security,while maintaining a high-quality reconstruction of images at the receiver *** proposed framework allows image watermarking based on the Discrete Cosine Transform(DCT)merged with the Singular Value Decomposition(SVD)in the so-called DCT-SVD *** addition,image encryption is implemented based on chaos and DNA *** encrypted watermarked images are then transmitted through the wireless SC-fDMA *** linearMinimumMean Square Error(MMSE)equalizer is investigated in this paper to mitigate the effect of channel fading and noise on the transmitted *** subcarrier mapping schemes,namely localized and interleaved schemes,are compared in this *** study depends on different channelmodels,namely PedestrianAandVehicularA,with a modulation technique namedQuadratureAmplitude Modulation(QAM).Extensive simulation experiments are conducted and introduced in this paper for efficient transmission of encrypted watermarked *** addition,different variants of SC-fDMA bas

关键词： Cybersecurity applications image transmission channel models modulation techniques watermarking and encryption

Wood anatomy chronologies of Scots pine in the foothills of the Western Sayan(Siberia)

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Journal of forestry Research 2024年第3期35卷 13-27页

作者： Elena A.Babushkina Dmitry R.Dergunov Mikhail S.Zharkov Liliana V.Belokopytova Dina f.Zhirnova Bao Yang Jingjing Liu Xiaomei Peng Eugene A.Vaganov Khakass Technical Institute Siberian Federal UniversityAbakan 655017Russia Institute of Ecology and Geography Siberian Federal UniversityKrasnoyarsk 660036Russia Mathematical Methods and IT Department Siberian Federal UniversityKrasnoyarsk 660036Russia Key Laboratory of Desert and Desertification Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000People's Republic of China School of Geographic and Oceanographic Sciences Nanjing UniversityNanjing 210093People's Republic of China Department of Dendroecology V.N.Sukachev Institute of ForestSiberian Branch of the Russian Academy of ScienceKrasnoyarsk 660036Russia

Recent methodological advances in quantitative wood anatomy have provided new insights into the climatic responses of radial growth at the scale of cell structure of tree rings. This study considered long-term chronologies of tracheid measurements, indexed by a novel approach to separate their specific climatic responses from signal recorded in cell production(closely reflected in tree-ring width). To fill gaps in understanding the impact of climate on conifer xylem structure, Scots pine(Pinus sylvestris L.)trees > 200 years old were selected within the forest-steppe zone in southern Siberia. Such habitats undergo mild moisture deficits and the resulting climatic regulation of growth processes. Mean and maximum values of cell radial diameter and cell wall thickness were recorded for each tree *** a low level of climatogenic stress, components of cell chronologies independent of cambial activity were separated to obtain significant climatic signals revealing the timing of the specific stages of tracheid differentiation. Cell expansion lasted from mid-April to July and was impacted similarly to tree-ring width(stimulated by precipitation and stressed by heat), maximum cell size formed late June. A switch in the climatic responses of mean anatomical traits indicated transition to latewood in mid-July. Secondary wall deposition lasted until mid-September, suppressed by end of season temperatures. Generally, anatomical climatic responses were modulated by a less dry May and September compared with summer months.

关键词： Quantitative wood anatomy Cell radial size Cell wall thickness Pinus sylvestris Climatic response

Electrochemical Realization of 3D Interconnected MoS_(3)/PPy Nanowire frameworks as Sulfur-Equivalent Cathode Materials for Li-S Batteries

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Energy & Environmental Materials 2024年第2期7卷 9-17页

作者： Hongtao Yu Andreas Siebert Shilin Mei Raul Garcia-Diez Roberto félix Ting Quan Yaolin Xu Johannes frisch Regan G.Wilks Marcus Bär Chun Pei Yan Lu Department for Electrochemical Energy Storage Helmholtz-Zentrum Berlin für Materialien und Energie GmbH(HZB)Hahn-Meitner Platz 114109 BerlinGermany Guangdong Province Key Laboratory of Durability for Marine Civil Engineering School of Civil EngineeringShenzhen UniversityShenzhenGuangdong 518060China Department of Interface Design HZBAlbert-Einstein-Str.1512489 BerlinGermany Energy Materials In-Situ Laboratory Berlin(EMIL) Albert-Einstein-Str.1512489 BerlinGermany Helmholtz-Institute Erlangen-Nürnberg for Renewable Energy(HI ERN) Albert-Einstein-Str.1512489 BerlinGermany Department of Chemistry and Pharmacy Friedrich-Alexander-Universität Erlangen-NürnbergEgerlandstr.391058Erlangen Germany Institute of Chemistry University of Potsdam14467Potsdam Germany

The development of freestanding and binder-free electrode is an effective approach to perform the inherent capacity of active materials and promote the mechanism study by minimizing the interference from ***,we construct a freestanding cathode composed of MoS_(3)/PPy nanowires(NWs)deposited on porous nickel foam(Nf)(MoS_(3)/PPy/Nf)through electrochemical methods,which can work efficiently as sulfur-equivalent cathode material for Li-S *** structural stability of the MoS_(3)/PPy/Nf cathode is greatly enhanced due to its significant tolerance to the volume expansion of MoS_(3)during the lithiation process,which we ascribe to the flexible 3D framework of PPy NWs,leading to superior cycling performance compared to the bulk-MoS_(3)/Nf *** the interference of binder and carbon additives,the evolution of the chemical and electronic structure of Mo and S species during the discharge/charge was studied by X-ray absorption near-edge spectroscopy(XANES).The formation of lithium polysulfides was excluded as the driving cathode reaction mechanism,suggesting the great potential of MoS_(3)as a promising sulfur-equivalent cathode material to evade the shuttle effect for Li-S *** present study successfully demonstrates the importance of structural design of freestanding electrode enhancing the cycling performances and revealing the corresponding mechanisms.

关键词： 3D-Network electrochemical lithium-sulfur battery MoS_(3) PPy

氮碳包封fe_(3)C纳米颗粒作为高效富氧还原电催化剂

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Science China Materials 2024年第3期67卷 762-770页

作者：汪翠萍李智雷杰李松 Stijn f.L.Mertens 胡劲松 School of Chemical Engineering Anhui Province Key Laboratory of Specialty PolymersAnhui University of Science and TechnologyHuainan 232001China Department of Chemistry Energy Lancaster and Materials Science LancasterLancaster UniversityLancaster LA14YBUnited Kingdom Institute of Energy Hefei Comprehensive National Science CenterHefei 230031China

高活性MOf基催化剂的设计和合成为促进动力学不利的氧还原反应(ORR)过程开辟了新的途径.本研究通过在ZIf-8前驱体表面涂覆二茂铁甲酸,然后进行两步炭化工艺,设计和制备了一种具有新型结构的高效电催化剂,以提高ORR性能.两步炭化过程对... 详细信息

高活性MOf基催化剂的设计和合成为促进动力学不利的氧还原反应(ORR)过程开辟了新的途径.本研究通过在ZIf-8前驱体表面涂覆二茂铁甲酸,然后进行两步炭化工艺,设计和制备了一种具有新型结构的高效电催化剂,以提高ORR性能.两步炭化过程对于将热解fe_(3)C纳米颗粒封装到碳纳米管(CNTs)中以及将fe单原子隔离到N掺杂碳(NC)基体上至关重要.此外,fe元素的相对含量对优化催化剂的ORR性能至关重要.所制得fe_(3)C@CNTs/NC-M催化剂结构先进,在碱性溶液中表现出良好的长期稳定性和电催化ORR性能,其半波电位和极限电流分别达到0.941 V和6.31 mA cm^(-2).此外,该电催化剂在甲醇溶液中具有较强的耐受性和良好的稳定性.fe_(3)C@CNTs/NC-M锌空气电池(ZAB)具有1.525 V的开路电位,420 mA cm^(-2)时的峰值功率密度为348 mW cm^(-2),10 mA cm^(-2)时的最大容量为843 mA h g_(Zn)^(-1).因此,这种合成策略为构建具有有效和稳定的ORR性能的MOf基电催化材料提供了一条有效途径.

关键词： metal-organic frameworks carbon nanotubes N-doped carbon matrix oxygen reduction reaction Zn-air battery

Theories and Practice in Prevention and Treatment Principles in Relation to Chinese Herbal Medicine and Bone Loss

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Journal of Traditional Chinese Medicine 2004年第2期24卷 88-92页

作者：徐红 David lawson School of Health Sciences Victoria University PO Box 14428 Melbourne City 8001 Australia

Osteoporosis is a world wide problem that is increasing in significance as the global population both increases and ages. While osteoporosis has been extensively studied in recent years, the utilization of Traditional Chinese Herbal Medicine for the prevention and treatment of this condition have seldom been examined in the Western world. This paper reviews the theories and the literature that relate to prevention and treatment of bone loss at the time of menopause according to the principles of Traditional Chinese Herbal Medicine. Practical developments in these areas are also illustrated in this paper based on the authors' research findings in recent studies.

关键词：理论实践预防措施治疗原则中草药骨骼系统骨质疏松症

Melting of hydrous pyroxenites with alkali amphiboles in the continental mantle:*** element compositions of melts and minerals

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Geoscience frontiers 2024年第1期15卷 50-68页

作者： Stephen f.foley Isra S.Ezad School of Natural Sciences Macquarie UniversityNorth RydeNew South Wales 2109Australia Research School of Earth Sciences Australian National UniversityCanberraACT 2601Australia

The trace element compositions of melts and minerals from high-pressure experiments on hydrous pyroxenites containing K-richterite are presented. The experiments used mixtures of a third each of the natural minerals clinopyroxene, phlogopite and K-richterite, some with the addition of 5% of an accessory phase ilmenite, rutile or apatite. Although the major element compositions of melts resemble natural lamproites, the trace element contents of most trace elements from the three-mineral mixture are much lower than in lamproites. Apatite is required in the source to provide high abundances of the rare earth elements, and either rutile and/or ilmenite is required to provide the high field strength elements Ti, Nb, Ta, Zr and Hf. Phlogopite controls the high levels of Rb, Cs and *** abundances of trace elements in the various starting mixtures vary strongly because of the use of natural minerals, we calculated mineral/melt partition coefficients (DMin/melt) using mineral modes and melting reactions and present trace element patterns for different degrees of partial melting of hydrous pyroxenites. Rb, Cs and Ba are compatible in phlogopite and the partition coefficient ratio phlogopite/K-richterite is high for Ba (136) and Rb (12). All melts have low contents of most of the first row transition elements, particularly Ni and Cu ((0.1-0.01)×primitive mantle). Nickel has high DMin/melt for all the major minerals (12 for K-richterite, 9.2 for phlogopite and 5.6 for Cpx) and so behaves at least as compatibly as in melting of peridotites. fluorine/chlorine ratios in melts are high and DMin/melt for fluorine decreases in the order apatite (2.2) > phlogopite (1.5) > K-richterite (0.87). The requirement for apatite and at least one Ti-oxide in the source of natural lamproites holds for mica pyroxenites that lack K-richterite. The results are used to model isotopic ageing in hydrous pyroxenite source rocks: phlogopite controls Sr isotopes, so that lamproites with relatively l

关键词： Hydrous pyroxenite Lamproite Trace elements Phlogopite K-richterite Apatite

Transformer for the Design of Automatic Control Systems with Prefilters

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World Journal of Engineering and Technology 2024年第3期12卷 575-586页

作者： Isaac Hughes John f. O’Brien Department of Electrical Engineering and Computer Science University of Wyoming Laramie USA

A machine learning model, using the transformer architecture, is used to design a feedback compensator and prefilter for various simulated plants. The output of the transformer is a sequence of compensator and prefilter parameters. The compensator and prefilter are linear models, preserving the ability to analyze the system with linear control theory. The input to the network is a window of recent reference and output samples. The goal of the transformer is to minimize tracking error at each time step. The plants under consideration range from simple to challenging. The more difficult plants contain closely spaced, lightly damped, complex conjugate pairs of poles and zeros. Results are compared to PID controllers tuned for a similar crossover frequency and optimal phase margin. for simple plants, the transformer converges to solutions which overly rely on the prefilter, neglecting the maximization of negative feedback. for more complex plants, the transformer designs a compensator and prefilter with more desirable qualities. In all cases, the transformer can start with random model parameters and modify them to minimize tracking error on the step reference.

关键词： feedback Machine Learning Compensator Design

Artificial kidney: Challenges and opportunities

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World Journal of Transplantation 2024年第1期14卷 42-47页

作者： filippos f Karageorgos Stavros Neiros Konstantina-Eleni Karakasi Stella Vasileiadou Georgios Katsanos Nikolaos Antoniadis Georgios Tsoulfas Department of Transplantation Surgery Center for Research and Innovation in Solid Organ TransplantationAristotle University School of MedicineThessaloniki 54642Greece

This review aims to present the developments occurring in the field of artificial organs and particularly focuses on the presentation of developments in artificial *** challenges for biomedical engineering involved in overcoming the potential difficulties are showcased,as well as the importance of interdisciplinary collaboration in this marriage of medicine and *** this review,modern artificial kidneys and the research efforts trying to provide and promise artificial kidneys are *** what are the problems faced by each technology and to what extent is the effort enough to date?

关键词： Artificial kidney Implantable kidney Hemodialysis Peritoneal dialysis Endstage kidney disease

Mining, Bridges, Opium, and Guns： Chinese Investment and State Power in a Late Qing frontier

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frontiers of History in China 2015年第3期10卷 372-394页

作者： Joseph lawson School of History Classics and Archaeology Newcastle University Newcastle upon Tyne NE17RU UK

In the last three decades of its rule, the Qing government attempted to establish Chinese-style administration in many of the empire＇s non-Hart territories, and, in conjunction with non-government actors, foster land cultivation, Han migration, Chinese education, and industries such as mining. This paper investigates these processes in Liangshan, in upland Southwest China. Here, attempts to establish Chinese administration came only in 1907, after a period of substantial private and state investment in mining, transport infrastructure, and, to a lesser extent, land cultivation. Government officials often assumed that such things would aid the political integration in China, but as this paper argues, the consequences were more complicated than that. Although better transport simplified the logistics of government military campaigns, increased commercial activity in the region also allowed its indigenes to acquire firearms for the first time.

关键词： mining opium road gun Liangshan Yi