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On the Relationship Between the Baum-Katz-Spitzer Complete Convergence Theorem and the Law of the Iterated Logarithm

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Acta Mathematica Sinica,English Series 2007年第4期23卷 599-612页

作者： De Li LI Andrew ROSALSKY andrei VOLODIN Department o/Mathematical Sciences Lakehead University Thunder Bay ON Canada P7B 5E1 Department of Statistics University of Florida Gainesville FL 32611 USA Department of Mathematics and Statistics University of Regina Regina SK Canada S4S 0A2

For a sequence of i.i.d. Banach space-valued random variables {Xn; n ≥ 1} and a sequence of positive constants {an; n ≥ 1}, the relationship between the Baum-Katz-Spitzer complete convergence theorem and the law of the iterated logarithm is investigated. Sets of conditions are provided under which （i） lim sup n→∞ ｜｜Sn｜｜/an〈∞ *** ∞ ∑n=1（1/n）P（｜｜Sn｜｜/an ≥ε〈∞for all ε 〉 λ for some constant λ ∈ [0, ∞） are equivalent;（ii） For all constants λ ∈ [0, ∞）,lim sup ｜｜Sn｜｜/an =λ *** ^∞∑ n=1（1/n） P（｜｜Sn｜｜/an ≥ε）{〈∞, if ε〉λ =∞,if ε〈λare equivalent. In general, no geometric conditions are imposed on the underlying Banach space. Corollaries are presented and new results are obtained even in the case of real-valued random variables.

关键词： partial sums of i.i.d. Banach space-valued random variables Baum-Katz-Spitzer complete convergence theorem law of the iterated logarithm almost sure convergence

Simulation modelling of potato virus Y spread in relation to initial inoculum and vector activity

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Journal of Integrative Agriculture 2020年第2期19卷 376-388页

作者： Andrew GALIMBERTI andrei ALYOKHIN Hongchun QU Jason ROSE School of Biology and Ecology University of MaineOronoME 04469USA Eastern New York Commercial Horticulture Program Cornell Cooperative ExtensionPlattsburghNY 12901USA College of Automation Chongqing University of Posts and TelecommunicationsChongqing 400065P.R.China

Potato virus Y(PVY)is a non-persistent virus that is transmitted by many aphid species and causes significant damage to potato *** constructed a spatially-explicit model simulating PVY spread in a potato field and used it to investigate possible effects of transmission efficiency,initial inoculum levels,vector behavior,vector abundance,and timing of peak vector activity on PVY incidence at the end of a simulated growing *** PVY incidence in planted seed resulted in lower virus infection at the end of the ***,when populations of efficient PVY vectors were high,significant PVY spread occurred even when initial virus inoculum was ***-colonizing aphids were more important for PVY spread compared to colonizing aphids,particularly at high *** early-season peak in the numbers of noncolonizing aphids resulted in the highest number of infected plants in the end of the season,while mid-and late-season peaks caused relatively little virus *** results highlight the importance of integrating different techniques to prevent the number of PVY-infected plants from exceeding economically acceptable levels instead of trying to control aphids within potato *** management plans should be implemented very early in a growing season.

关键词： potato virus Y spatially-explicit modelling aphids virus spread integrated pest management

A necessary and sufficient condition for a surface sum of two handlebodies to be a handlebody

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Science China Mathematics 2020年第10期63卷 1997-2004页

作者： Fengchun Lei He Liu Fengling Li andrei Vesnin School of Mathematical Sciences Dalian University of TechnologyDalian 116024China Regional Scientific and Educational Mathematical Center Department of Mechanics and MathematicsTomsk State UniversityTomsk 634050Russia

The main results of the paper are that we give a necessary and sufficient condition for a surface sum of two handlebodies along a connected surface to be a handlebody as follows:(1)The annulus sum H=H1∪AH2 of two handlebodies H1 and H2 is a handlebody if and only if the core curve of A is a longitude for either H1 or H2;(2)Let H=H1∪Sg,b H2 be a surface sum of two handlebodies H1 and H2 along a connected surface S=Sg,b,b 1,ni=g(Hi)2,i=1,*** that S is incompressible in both H1 and *** H is a handlebody if and only if there exists a basis J={J1,...,Jm}with a partition(J1,J2)of J such that J1 is primitive in H1 and J2 is primitive in H2.

关键词： handlebody surface sum of 3-manifolds free group

Life-Cycle and Seismic Fragility Assessment of Code-Conforming Reinforced Concrete and Steel Structures in Bucharest, Romania

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International Journal of Disaster Risk Science 2018年第2期9卷 263-274页

作者： Florin Pavel Ileana Calotescu Dan Stanescu andrei Badiu Technical University of Civil Engineering Bucharest

In this article, the fragility of reinforced concrete and steel structures in Bucharest, a city of high seismic hazard, designed using the recent building codes in Romania, is assessed. A total of 24 reinforced concrete and steel structures with heights varying from five stories to 13 stories were analyzed. Their seismic fragility was evaluated using two procedures from the literature. In the first procedure(SPO2 FRAG), the fragility was derived based on the pushover curves using the SPO2 IDA algorithm, while in the second procedure(FRACAS), the fragility was derived from nonlinear time-history analyses. The analyzed structures were designed for three levels of peak ground accelerations, corresponding to mean return periods of 100,225, and 475 years. Subsequently, the damage assessment of the analyzed structures was performed using ground motions generated from a Monte-Carlo simulated earthquake catalogue for the Vrancea intermediate-depth seismic source. The damage degrees that were estimated using the SPO2 FRAG approach are higher than those estimated using the FRACAS approach. The life-cycle analysis of the structures shows that a further increase of the design peak ground acceleration for Bucharest is feasible from an economic point of view using the SPO2 FRAG ***, based on the FRACAS results, the opposite conclusion can be drawn. Finally, generic lognormal fragility functions are proposed as a function of building height and structural system.

关键词： Bucharest Building damage degree Building life-cycle analysis Monte-Carlo simulated earthquake catalogue Seismic risk Vrancea seismic source

Body Building on Diamonds

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Journal of Bionic Engineering 2009年第1期6卷 14-17页

作者： andrei P. Sommer Tim Scharnweber Hans-Joerg Fecht Institute of Micro and Nanomaterials University of UlmUlm 89081Germany Institute for Biological Interfaces Research Center KarlsruheKarlsruhe 76021Germany Institute for Nanotechnology Research Center Karlsruhe Karlsruhe 76021Germany

Whereas conservative therapies aim to stall the advance of disease,regenerative medicine strives to reverse *** capacity of most tissues to regenerate derives from stem cells,but there are a number of barriers which have to be circumvented before it will be possible to use stem-cell-based *** therapies,however,are expected to improve human health enormously, and knowledge gained from studying stem cells in culture and in model organisms is now laying the groundwork for a new era of regenerative *** of the most prominent methods to study stem cell differentiation is to let them to form embryoid *** favourable conditions any stem cell line will form embryoid ***,the mechanism of the formation of embryoid bodies is not very well understood,and to produce them in the laboratory is in no way trivial-an important technical barrier in stem cell ***,the embryoid body cultivation step has been successfully circumvented for the derivation of osteogenic cultures of embryonic stem *** we report on a simple and reusable system to cultivate embryoid bodies in extremely short *** method is inspired by the principles that lead to the establishment of the biomimetic triangle.

关键词： biomimetic triangle stem cells embryoid bodies nanobionics nanocrystalline diamond

Introspection on improper seismic retrofit of Basilica Santa Maria di Collemaggio after 2009 Italian earthquake

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Earthquake Engineering and Engineering Vibration 2011年第1期10卷 153-161页

作者： Gian Paolo Cimellaro andrei M. Reinhorn Alessandro De Stefano Department of Structural & Geotechnical Engineering (DISTR) Politecnico di Torino Department of Civil Structural & Environmental Engineering University at Buffalo The State University of New York

The 2009 L’Aquila, Italy earthquake highlighted the seismic vulnerability of historic masonry building structures due to improper ＂strengthening＂ retrofit work that has been done in the last 50 years. Italian seismic standards recommend the use of traditional reinforcement techniques such as replacing the original wooden roof structure with new reinforced concrete （RC） or steel elements, inserting RC tie-beams in the masonry and new RC floors, and using RC jacketing on the shear walls. The L’Aquila earthquake revealed the numerous limitations of these interventions, because they led to increased seismic forces （due to greater additional weight） and to deformation incompatibilities of the incorporated elements with the existing masonry walls. This paper provides a discussion of technical issues pertaining to the seismic retrofit of the Santa Maria di Collemaggio Basilica and in particular, the limitations of the last （2000） retrofit intervention. Considerable damage was caused to the church because of questionable actions and incorrect and improper technical choices.

关键词： seismic vulnerability historic masonry building wooden roof structure seismic retrofit L’Aquila earthquake

Countering DNS Amplification Attacks Based on Analysis of Outgoing Traffic

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Journal of Communications and Information Networks 2023年第2期8卷 111-121页

作者： Evgeny Sagatov Samara Mayhoub andrei Sukhov Prasad Calyam Sevastopol State University(SevSU) Universitetskaya ul.33Sevastopol 99026Russia Samara National Research University Moskovskoe sh.34Samara 443086Russia University of Missouri-Columbia 221 Naka HallColumbia MO 65211USA

Domain name system(DNS)amplification distributed denial of service(DDoS)attacks are one of the popular types of intrusions that involve accessing DNS servers on behalf of the *** this case,the size of the response is many times greater than the size of the request,in which the source of the request is substituted for the address of the *** paper presents an original method for countering DNS amplification DDoS *** novelty of our approach lies in the analysis of outgoing traffic from the victim’s *** servers used for amplification attacks are easily detected in Internet control message protocol(ICMP)packet headers(type 3,code 3)in outgoing *** packets of this type are generated when accessing closed user datagram protocol(UDP)ports of the victim,which are randomly assigned by the Saddam attack *** prevent such attacks,we used a Linux utility and a software-defined network(SDN)module that we previously developed to protect against port *** Linux utility showed the highest efficiency of 99.8%,i.e.,only two attack packets out of a thousand reached the victim server.

关键词： DNS amplification attacks outgoing traffic analysis port scanning attack network intrusion qualification attributes

Synaptic mechanisms of cadmium neurotoxicity

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Neural Regeneration Research 2021年第9期16卷 1762-1763页

作者： andrei N.Tsentsevitsky Alexey M.Petrov Laboratory of Biophysics of Synaptic Processes Kazan Institute of Biochemistry and BiophysicsFederal Research Center“Kazan Scientific Center of RAS”2/31 Lobachevsky StreetBox 30Kazan420111Russia University 49 Butlerova StreetKazan420012Russia

Cadmium(Cd) is a toxic heavy metal ubiquitously distributed in the environment(water, air, food, smoke) with extreme ability to accumulate in the human body due to its delayed clearance(half-life time 15–30 years).

关键词： cadmium extreme accumulate

Stress states of thawed soil subgrade

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Research in Cold and Arid Regions 2015年第4期7卷 348-353页

作者： andrei Petriaev Construction of Roads Transport Complex Department St.Petersburg State Transport University

The article presents the field measurement results of the stress states of roadbed thawed soil subgrade during the passage of trains. The dependences of the vertical and horizontal stresses on the velocity of the roll... 详细信息

关键词： dynamic vibration impact vertical and horizontal stresses thawing subgrade stress rise rate