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Why the Incoherent Paradigm Is for the Future Wireless Networks?

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Communications and Network 2023年第3期15卷 65-82页

作者： valeri kontorovich Electrical Engineering Department Communications Section CINVESTAV-IPN Mexico City Mexico

This material is aimed to attract attention to the “incoherent approach for power NOMA-RIS-MIMO transmission in wireless channels”. Such kind of approach might be successfully applied in future dense networks formed by High-Speed Vehicles (HSV networks, etc.). Those scenarios take place in doubly selective communication channels typical for such kind of radio networks. The proposal for the presented hereafter incoherent view (“paradigm”) is based on several basic principles: 1) Shift from the “coherent “ideology”, i.e. rejection of the application of any type of Channel State Information (CSI, CSIT);2) Application of the so-called “invariant” to the communication channel’s features (distortions) modulation technique together with its incoherent demodulation;3) Orthogonal channel decomposition by means of “universal” eigen basis (in the form of Prolate Spheroidal Wave Functions, PSWF) as “artificial trajectories” of wave propagation;4) Chaotic filtering (chaos parameter settings as UE signatures) together with sequential multiuser parallel detection algorithms for users’ identification (classification). It is shown that the proposed approach might provide an effective use of the radio resource and it is relatively simple for implementation.

关键词： Incoherent Processing Universal Eigen Functions Chaos Filtering Invariant Modulation

Characteristics of Sequential Detection in Cognitive Radio Networks

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通讯和计算机（中英文版） 2012年第5期9卷 587-595页

作者： Oscar Filio Rodriguez valeri kontorovich Serguei Primak Department of Electrical and Computer Engineering The University of Western Ontario London Ontario N6A 5B9 Canada Electrical Engineering Department Telecommunications Section CINVESTA V-IPN Av. IPN 2508 Col. San Pedro Zacatenco C.P. 07360 Mexico City Mexico

Sequential Analysis is an effective detection procedure for spectrum sensing in Cognitive Radio (CR) Networks. On average, given PFA (probability of false alarm) and PMD and low SNR regime, it requires less independent samples for the primary users (PU) detection comparing to the Neyman-Pearson (NP) test. This paper deals with the evaluation of the cumulants of the distribution (PDF) of random time of the sequential analysis, however, for simplicity we consider only Gaussian approximation. It is assumed that the PU and secondary users (SU) are sharing the same frequency bandwidth and for spectrum sensing SU"s apply incoherent diversity combining of diversity branches with fading described by the Generalized Gaussian (GG) model.

关键词：无线电网络连续检测时间序列分析用户检测高斯近似认知无线电 PDF格式检测程序

Extravasated contrast volumetric assessment on computed tomography angiography in gastrointestinal bleeding:A useful predictor of positive angiographic findings

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World Journal of Radiology 2024年第5期16卷 115-127页

作者： Laura Maria Cacioppa Chiara Floridi Alessandra Bruno NicolòRossini Tommaso valeri Alessandra Borgheresi Riccardo Inchingolo Francesco Cortese Giacomo Novelli Alessandro Felicioli Mario Torresi Pietro Boscarato Letizia Ottaviani Andrea Giovagnoni Division of Interventional Radiology Department of Radiological SciencesUniversity Politecnica Delle MarcheAncona 60126Italy Department of Clinical Special and Dental SciencesUniversity Politecnica Delle MarcheAncona 60126Italy Division of Radiology Department of Radiological SciencesUniversity Hospital"Azienda Ospedaliero Universitaria Delle Marche"Ancona 60126Italy Interventional Radiology Unit "F Miulli"Regional General HospitalAcquaviva delle Fonti 70021Italy Department of Radiology IRCCS INRCAAncona 60126Italy

BACKGROUND Gastrointestinal bleeding(GIB)is a severe and potentially life-threatening condition,especially in cases of delayed *** tomography angiography(CTA)plays a pivotal role in the early identification of upper and lower GIB and in the prompt treatment of the *** To determine whether a volumetric estimation of the extravasated contrast at CTA in GIB may be a predictor of subsequent positive angiographic *** In this retrospective single-centre study,35 patients(22 men;median age 69 years;range 16-92 years)admitted to our institution for active GIB detected at CTA and further submitted to catheter angiography between January 2018 and February 2022 were ***-three(65.7%)patients underwent endoscopy before *** volumetry was evaluated in both arterial and venous phases via a semi-automated dedicated *** rate was obtained from volume change between the two phases and standardised for unit *** were divided into two groups,according to the angiographic signs and their concordance with *** Upper bleeding accounted for 42.9%and lower GIB for 57.1%.Mean haemoglobin value at the admission was 7.7 g/dL.A concordance between positive CTA and direct angiographic bleeding signs was found in 19(54.3%)*** no significant differences in terms of bleeding volume in the arterial phase(0.55 mL vs 0.33 mL,P=0.35),a statistically significant volume increase in the venous phase was identified in the group of patients with positive angiography(2.06 mL vs 0.9 mL,P=0.02).In the latter patient group,a significant increase in bleeding rate was also detected(2.18 mL/min vs 0.19 mL/min,P=0.02).CONCLUSION In GIB of any origin,extravasated contrast volumetric analysis at CTA could be a predictor of positive angiography and may help in avoiding further unnecessary procedures.

关键词： Gastrointestinal haemorrhage Computed tomography angiography Volumetric analysis Computer-assisted image interpretation Therapeutic embolization Transcatheter arterial embolization

Comparative equilibrium studies of sorption of Pb(Ⅱ) ions by sodium and calcium alginate

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Journal of Environmental Sciences 2008年第7期20卷 827-831页

作者： KHOTIMCHENKO Maxim KOVALEV valeri KHOTIMCHENKO Yuri Department of pharmacy Vladivostok State Medical UniversityVladivostok 690990Russia Laboratory of Pharmacology Institute of Marine BiologyFar East Branch of Russian Academy of SciencesVladivostok 690041Russia. Laboratory of Pharmacology Institute of Marine BiologyFar East Branch of Russian Academy of SciencesVladivostok 690041Russia.Department of pharmacyVladivostok State Medical UniversityVladivostok 690990Russia

The absorption of Pb(Ⅱ) ions from aqueous solution by different alginate compounds was studied in a batch sorption *** soluble sodium alginate and insoluble calcium alginate beads were *** lead-binding capacity of both alginate compounds was highest within the pH range *** binding capacities and rates of Pb(lI) ions by alginate compounds were *** Langmuir,Freundlich,and Bruneaur,Emmet and Teller (BET) sorption models were applied to describe the isotherms and isotherm con...

关键词： heavy metal lead equilibrium study alginate wastewater

Modulating the growth of cysteine-capped cadmium sulfide quantum dots with enzymatically produced hydrogen peroxide

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Nano Research 2017年第6期10卷 1932-1941页

作者： Ruta Grinyte Javier Barroso Laura Saa valeri Pavlov Biosensing Unit CIC BiomaGUNE Parque Tecnologico de San Sebastian Paseo Miramon 182 Donostia-San Sebastian 20014 Spain

Cysteine （CSH） readily stabilizes cadmium sulfide quantum dots （CdS QDs） that grow in aqueous buffered solutions. The oxidation of CSH by hydrogen peroxide （H202） at room temperature yields cystine （CSSC）, which is less efficient in stabilizing CdS QDs compared to CSH. Herein, we demonstrate that such oxidation causes a decrease in the formation rate of CSH-capped CdS QDs from Cd^2＋ and S^2- ions. For the first time, we combined the oxidation of CSH with the glucose oxidase （GOx）-assisted biocatalytic oxidation of D-glucose, which leads to a buildup of H2O2 in the reaction mixture. The enzymatically modulated in situ growth of CdS QDs was monitored using two techniques： fluorescence spectroscopy and photoelectrochemical （PEC） analysis. This system enables quantification of GOx and glucose in human serum.

关键词： quantum dots photoelectrochemistry enzyme fluorescence hydrogen peroxide

HER2 inhibition in gastro-oesophageal cancer:A review drawing on lessons learned from breast cancer

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World Journal of Gastrointestinal Oncology 2018年第7期10卷 159-171页

作者： Hazel Lote Nicola valeri Ian Chau Centre for Molecular Pathology Institute of Cancer Research Department of Medicine Royal Marsden Hospital

Human epidermal growth factor receptor 2(HER2)-inhibition is an important therapeutic strategy in HER2-amplified gastro-oesophageal cancer(GOC).A significant proportion of GOC patients display HER2 amplification,yet HER2 inhibition in these patients has not displayed the success seen in HER2 amplified breast *** of the current evidence surrounding HER2 has been obtained from studies in breast cancer,and we are only recently beginning to improve our understanding of HER2-amplified *** there are numerous licensed HER2 inhibitors in breast cancer,trastuzumab remains the only licensed HER2 inhibitor for HER2-amplified *** trials investigating lapatinib,trastuzumab emtansine,pertuzumab and MM-111 in GOC have demonstrated disappointing results and have not yet changed the treatment *** deruxtecan may hold promise and is currently being investigated in phase Ⅱ ***2 amplified GOC differs from breast cancer due to inherent differences in the HER2 amino-truncation and mutation rate,loss of HER2 expression,alterations in HER2 signalling pathways and differences in insulin-like growth factor-1 receptor and MET *** alterations involving different micro RNA profiles in GOC as compared to breast cancer and intrinsic differences in the immune environment are likely to play a *** key to effective treatment of HER2 amplified GOC lies in understanding these mechanisms and tailoring HER2 inhibition for GOC patients in order to improve clinical outcomes.

关键词： Human epidermal growth factor receptor 2 Gastro-oesophageal cancer Trastuzumab Resistance Biomarkers Breast cancer

Analytical study on the dynamic displacement response of a curved track subjected to moving loads

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2013年第12期14卷 867-879页

作者： Ke-fei LI Wei-ning LIU valeri MARKINE Zhi-wei HAN School of Civil Engineering Beijing Jiaotong University Beijing MTR Construction Administration Corporation Railway Engineering Group Faculty of Civil Engineering and Geosciences Delft University of Technology

A closed-form out-of-plane dynamic displacement response of a curved track subjected to moving loads was *** track structure was modeled as a planar curved Timoshenko beam periodically supported by the double-layer spring-damping *** general dynamic displacement response induced by the moving loads along the curve on the elastic semi-infinite space was firstly obtained in the frequency domain,according to the Duhamel integral and the dynamic reciprocity *** the case of the periodic curved track structure subjected to moving loads,the dynamic displacement equation was simplified into a form of summation within the basic track cell instead of the *** transfer function for the curved track was expressed in the form of a transfer *** and series moving loads were involved in the calculation *** the verification of the analytical model,the mid-span vertical deflection of a simply support curved beam subjected to moving load was recalculated and compared with the same case in the *** research results indicate that:under the same moving loads,the displacement response of the curved track decreases slightly with the increasing track radius,and the displacement response of the curved track with the radius greater than or equal to 600 m is almost equivalent to the displacement response of the straight track;the frequency spectrum of the curved track is more abundant than that of the straight track,which may result in more wheel-rail resonance and rail corrugation in the curved lines.

关键词： Curved track Moving loads Dynamic displacement Analytical solution Transfer function

Experimental Research on Wave Transmission over Submerged Rubble-Mound Breakwaters

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China Ocean Engineering 2008年第4期22卷 575-584页

作者：左其华 valeri PENCHEV 李鹏 Dorina DRAGANCHEVA 王登婷 Nanjing Hydraulic Research Institute Black Sea Coastal Association 9000 VarnaBulgaria Bulgarian Ship Hydrodynamics Centre Bulgarian Academy of Sciences9003 VarnaBulgaria

This paper discusses some previous, and presents some new experimental results on wave transmission over submerged breakwaters. The objective of this study is to evaluate wave transmission coefficient and develop a two-dimensional （2D） model as an improvement to the existing wave transmission coefficient models. Factors which affect wave transmission over stbmerged breakwaters are discussed through a series of laboratory experiments. Basic recommendations for evaluation and design of submerged rubble-monud breakwaters are presented. From the test results, a calculation formula of wave transmission coefficient is proposed.

关键词： submerged rubble breakwater wave transmission coefficient wave dissipation laboratory experiment

Metro train-induced vibrations on historic buildings in Chengdu,China

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第10期12卷 782-793页

作者： Meng MA valeri MARKINE Wei-ning LIU Yang YUAN Feng ZHANG School of Civil Engineering Beijing Jiaotong University Beijing 100044 China Section of Road and Railway Engineering Department of Design and Construction Delft University of Technology Delft 2600GA the Netherlands

In this paper, the vibration influence on a monument caused by Chengdu Subway Line 2 is analyzed. Due to its elaborate and unique design, both structural and architectural damages should be avoided. First, the allowable root mean square （RMS） velocity at the foundation of the monument is derived and a site measurement is performed to obtain the background vibrations induced by road traffic. In addition, a train-track coupled model and 3D tunnel-soil-structure coupled finite element models are built to predict the dynamic response of the monument. Prediction models are checked by site measurement in Beijing Subway Line 5. Different kinds of fasteners and train speeds are compared and discussed as well. Results show that：（1） At a train speed of 72 km/h, all the traffic vibrations exceed the low limit no matter what kind of fastener is used, which is mainly due to the contribution of road traffic. Slowing down train speeds can cause effective vibration attenuation; （2） Vibrations drop dramatically with the train speed from 65 to 58 km/h. When the train speed is lower than 58 krn/h, vibrations are lower than allowable value even if the contribution of road traffic is considered.

关键词： Traffic vibrations Historic buildings Vibration prediction Numerical simulation _