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控制理论与应用（英文版） 2013年第2期11卷 180-185页

作者： Ruijie ZHAO Xiaoping lai school of Mechanical Electrical and Information Engineering Shandong University at Weihai Institute of Information and Control Hangzhou Dianzi University

This paper focuses on the design of two-dimensional （2D） quadrantally symmetric finite impulse response （FIR） filters, and presents three very efficient algorithms for the weighted least squares （WLs） design with a weight matrix that assigns four different weights to four different frequency bands. The first algorithm seeks for iterative solutions to the matrix equation describing the optimality condition of the design problem. The second algorithm aims at the limit solution of the solution sequence to the first algorithm, analytically obtained by using matrix diagonalization techniques. The third algorithm belongs to the category of iterative reweighting techniques. It uses the second algorithm as its iteration core, and aims at reducing the maximum magnitude error of the filter by iteratively adjusting the four entry values of the weight matrix. Design examples are provided to demonstrate the performance of the proposed algorithms.

关键词： 2D FIR filters Diagonalization Quadrantal symmetry WLs design

User centric dynamic web information visualization

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science China(Information sciences) 2013年第5期56卷 36-49页

作者： sALEHEEN shibli lai Wei Faculty of Information and Communication Technologies Swinburne University of TechnologyHawthorn 3122VictoriaAustralia

Visualization of information after retrieval from the World Wide Web is a very challenging task because of the huge amount of data in *** on rules,information is retrieved through mining techniques and then visualized in different *** web-graph is one way for users to visualize web data and its *** because of its huge size,the web-graph lacks simplicity for end *** clustering plays a very important role in reducing the complexity of the web graph by making it compact and simple,existing clustering techniques are insufficient to provide personalized visualization for ***,these clustering techniques end up showing the same clustered graph to every user,despite their varying *** work aims to make information visualization personalized based on user interests;to provide a good first impression of web information to end users;to make web navigation easier;and to create scope for further ***,we develop a system for clustering which first considers user interests and then visualizes the clustered web graph to make the information more useful to the end *** this paper,we present some experimental examples that show the improvements achieved by our approach over existing ones.

关键词： information retrieval user profile clustering personalization visualization

Experimental investigation on the wing-wake interaction at the mid stroke in hovering flight of dragonfly

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science China(Physics,Mechanics & Astronomy) 2012年第11期55卷 2167-2178页

作者： lai GuoJun sHEN GongXin FFFOM Laboratory School of Aeronautic Science and EngineeringBeihang UniversityBeijing 100191China

This paper focuses on flow structures of the wing-wake interaction between the hind wing and the wake of the forewing in hovering flight of a dragonfly since there are arguments whether the wing-wake interaction is useful or not.A mechanical flapping model with two tandem wings is used to study the *** the device,two identical simplified model wings are mounted to the flapping model and they are both scaled up to keep the Reynolds number similar to those of dragonfly in hovering flight since our experiment is conducted in a water *** kinetic pattern of dragonfly(Aeschna juncea) is chosen because of its special interesting asymmetry.A multi-slice phase-locked stereo particle image velocimetry(PIV) system is used to record flow structures around the hind wing at the mid downstroke(t/T=0.25) and the mid upstroke(t/T=0.75).To make comparison of the flow field between with and without the influence of the wake,flow structures around a single flapping wing(hind wing without the existence of the forewing) at these two stroke phases are also recorded.A local vortex identification scheme called swirling strength is applied to determine the vortices around the wing and they are visualized with the iso-surface of swirling *** paper also presents contour lines of z at each spanwise position of the hind wing,the vortex core position of the leading edge vortex(LEV) of hind wing with respect to the upper surface of hind wing,the circulation of the hind wing LEV at each spanwise position and so *** results show that dimension and strength of the hind wing LEV are impaired at the mid stroke in comparison with the single wing LEV because of the downwash from the *** results also reveal that a wake vortex from the forewing traverses the upper surface of the hind wing at the mid downstroke and its distance to the upper surface is about 40% of the wing chord *** the instant,the distance of the hind wing LEV to the upper surface is abo

关键词： dragonfly hovering flight particle image velocimetry (PIV) flow interaction leading edge vortex

ON THE EMBEDDING OF TOP IN THE CATEGORY OF sTRATIFIED L-TOPOLOGICAL sPACEs

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Chinese Annals of Mathematics,series B 2005年第2期26卷 219-228页

作者： lai Hongliang ZHANG Dexue Department of Mathematics Sichuan UniversityChengdu 610064China Department of Mathematics Sichuan UniversityChengdu 610064China

Let L be a meet continuous lattice. It is proved that the category Top of topological spaces can be embedded in the category of strati?ed L-topological spaces as a concretely both re?ective and core?ective full subcat... 详细信息

关键词： Continuous lattice L-topological space Re?ective subcategory Core-flective subcategory

Efficacy of 6-mercaptopurine treatment after azathioprine hypersensitivity in inflammatory bowel disease

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World Journal of Gastroenterology 2008年第27期14卷 4342-4346页

作者： Ferenc Nagy tamás Molnár Zoltán szepes Klaudia Farkas Tibor Nyári János Lonovics First Department of Medicine University of Szeged Faculty of Medicine Institute of Medical Informatics University of Szeged Faculty of Medicine

AIM:To investigate the efficacy of 6-mercaptopurine (6-MP) in cases of azathioprine (AZA) hypersensitivity in patients with inflammatory bowel disease. METHODs: Twenty nine previously confirmed Crohn’s disease (CD) (n = 14) and ulcerative colitis (UC) (n = 15) patients with a known previous (AZA) hypersensitivity reaction were studied prospectively. The 6-MP doses were gradually increased from 0.5 up to 1.0-1.5 mg/kg per day. Clinical activity indicies (CDAI/CAI), laboratory variables and daily doses of oral 5-AsA, corticosteroids, and 6-MP were assessed before and in the first, sixth and twelfth months of treatment. REsULTs: In 9 patients, 6-MP was withdrawn in the first 2 wk due to an early hypersensitivity reaction. Medication was ineffective within 6 mo in 6 CD patients, and myelotoxic reaction was observed in two. Data were evaluated at the end of the sixth month in 12 (8 UC, 4 CD) patients, and after the first year in 9 (6 UC, 3 CD) patients. CDAI decreased transiently at the end of the sixth month, but no significant changes were observed in the CDAI or the CAI values at the end of the year. Leukocyte counts (P = 0.01), CRP (P = 0.02), and serum iron (P = 0.05) values indicated decreased inflammatory reactions, especially in the UC patients at the end of the year, making the possibility to taper oral steroid doses. CONCLUsION: About one-third of the previously AZA- intolerant patients showed adverse effects on taking 6MP. In our series, 20 patients tolerated 6MP, but it was ineffective in 8 CD cases, and valuable mainly in ulcerative colitis patients.

关键词： Inflammatory bowel disease Azathioprine 6-mercaptopurine side effects Efficacy

New constructions for (multiparty) one-round key exchange with strong security

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science China(Information sciences) 2018年第5期61卷 332-337页

作者： Zheng YANG Junyu lai school of Computer science and Engineering Chongqing University of Technology Department of Computer science University of Helsinki school of Aeronautics and Astronautics University of Electronic Science and Technology of China

Dear editor,One-round key exchange(ORKE)represents a special class of two-message key *** enables two parties to establish a shared session key within only one communication *** first merit of ORKE is its communication efficiency,particularly because two parties are able to simultaneously run the protocol ***,the messages of two session participants(in an ORKE protocol)are completely independent.

关键词： New constructions for multiparty Eph DDH PFs

What is the effective key length for a block cipher: an attack on every practical block cipher

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science China(Information sciences) 2014年第7期57卷 138-148页

作者： HUANG JiaLin lai XueJia Cryptography and Information security Lab Department of Computer ScienceShanghai Jiaotong University

Recently,several important block ciphers are considered to be broken by the brute-force-like cryptanalysis,with a time complexity faster than the exhaustive key search by going over the entire key space but performing less than a full encryption for each possible *** by this observation,we describe a meetin-the-middle attack that can always be successfully mounted against any practical block ciphers with success probability *** data complexity of this attack is the smallest according to the unicity *** time complexity can be written as 2k(1-),where>0 for all practical block ***,the security bound that is commonly accepted is the length k of the given master *** our result we point out that actually this k-bit security is always overestimated and can never be reached because of the inevitable loss of the key *** amount of clever design can prevent it,but increments of the number of rounds can reduce this key loss as much as *** give more insight into the problem of the upper bound of effective key bits in block ciphers,and show a more accurate bound.A suggestion about the relationship between the key size and block size is *** is,when the number of rounds is fixed,it is better to take a key size equal to the block ***,effective key bits of many well-known block ciphers are calculated and analyzed,which also confirms their lower security margins than thought *** results in this article motivate us to reconsider the real complexity that a valid attack should compare to.

关键词： block cipher effective key bits meet-in-the-middle brute-force attack

The shanghai Cooperation Organization on Turkey’s Energy Agenda

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Asian Journal of Middle Eastern and Islamic studies 2019年第1期13卷 50-64,I0004页

作者： tamás Kozma Antall József Knowledge Centre BudapestHungary Doctoral school of Earth sciences University of PécsPécsHungary

Turkey’s energy policy has attracted a growing scholarly *** line with this tendency,this article aims at the assessment of Turkey’s energy relations with the shanghai Cooperation Organization(sCO).As the sCO has appeared more frequently in Turkish foreign policy discourse in the recent years,it can be considered a relevant direction where Turkey’s active energy diplomacy can be *** that Turkey’s energy aspirations are predominantly assessed from a Western point of view,the uniqueness of this article is that it combines the study of Turkey’s advancing Eastern relations and its energy policy endeavours.A central argument in this article is about the existing number of energy connections established between Turkey and the member states,observers and dialogue partners of sCO,which overwhelmingly operate at the bilateral level,while the energy framework of the sCO is yet to be filled with multilateral meaning for Turkey.

关键词： Energy policy natural gas shanghai Cooperation Organization Turkey

Weighted weak type (1,1) estimate for the Christ-Journé type commutator

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science China Mathematics 2018年第3期61卷 517-534页

作者： Yong Ding Xudong lai school of Mathematical sciences Beijing Normal University Beijing 100875 China Institute for Advanced study in Mathematics Harbin Institute of Technology Harbin 150001 China

Let K be the Calderón-Zygmund convolution kernel on R^d(d≥2).Christ and Journé defined the commutator associated with K and a∈L~∞(R^d)by T_af(x)=p.v.∫_(R^d)K(x-y)m_x,y^a·f(y)dy,which is an extension of the classical Calderón commutator. In this paper, we show that T_a is weighted weak type(1,1) bounded with A,1 weight for d≥2.

关键词： Christ-Journe type commutator weighted weak type(1 1) A1 weight

Behaviors of recycled aggregate concrete-filled steel tubular columns under eccentric loadings

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Frontiers of structural and Civil Engineering 2019年第3期13卷 628-639页

作者： Vivian W.Y.tam Jianzhuang XIAO sheng LIU Zixuan CHEN Department of structural Engineering Tongji UniversityShanghai 200092China University of Western sydney School of ComputingEngineering and Mathematics and Institute for Infrastructure EngineeringLocked Bag 1797PenrithNSW 2751Australia

The paper investigates the behaviors of recycled aggregate concrete-filled steel tubular(RACFsT)columns under eccentric loadings with the incorporation of expansive agents.A total of 16 RACFsT columns were tested in this *** main parameters varied in this study are recycled coarse aggregate replacement percentages(0%,30%,50%,70%,and 100%),expansive agent dosages(0%,8%,and 15%)and an eccentric distance of compressive load from the center of the column(0 and 40 mm).Experimental results showed that the ultimate stresses of RACFsT columns decreased with increasing recycled coarse aggregate replacement percentages but appropriate expansive agent dosages can reduce the decrement;the incorporation of expansive agent decreased the ultimate stresses of RACFsT columns but an appropriate dosage can increase the deformation *** recycled coarse aggregate replacement percentages have limited influence on the ultimate stresses of the RACFsT columns and has more effect than that of the normal aggregate concretesteel tubular columns.

关键词： concrete filled steel tubes recycled aggregate concrete columns expansive agent eccentric load