Special functions, transcendentals and their numerics

Cyclotomic polylogarithms are reviewed and new results concerning the special constants that occur are presented. This also allows some comments on previous literature results using PSLQ

Systematics of the cusp anomalous dimension

We study the velocity-dependent cusp anomalous dimension in supersymmetric Yang-Mills theory. In a paper by Correa, Maldacena, Sever, and one of the present authors, a scaling limit was identified in which the ladder diagrams are dominant and are mapped onto a Schrodinger problem. We show how to solve the latter in perturbation theory and provide an algorithm to compute the solution at any loop order. The answer is written in terms of harmonic polylogarithms. Moreover, we give evidence for two curious properties of the result. Firstly, we observe that the result can be written using a subset of harmonic polylogarithms only, at least up to six loops. Secondly, we show that in a light-like limit, only single zeta values appear in the asymptotic expansion, again up to six loops. We then extend the analysis of the scaling limit to systematically include subleading terms. This leads to a Schrodinger-type equation, but with an inhomogeneous term. We show how its solution can be computed in perturbation theory, in a way similar to the leading order case. Finally, we analyze the strong coupling limit of these subleading contributions and compare them to the string theory answer. We find agreement between the two calculations.Comment: 33 pages, 4 figures. Complete LO six-loop result added. Typos corrected. Version accepted for publicatio

Research and Design of a Routing Protocol in Large-Scale Wireless Sensor Networks

无线传感器网络，作为全球未来十大技术之一，集成了传感器技术、嵌入式计算技术、分布式信息处理和自组织网技术，可实时感知、采集、处理、传输网络分布区域内的各种信息数据，在军事国防、生物医疗、环境监测、抢险救灾、防恐反恐、危险区域远程控制等领域具有十分广阔的应用前景。 本文研究分析了无线传感器网络的已有路由协议，并针对大规模的无线传感器网络设计了一种树状路由协议，它根据节点地址信息来形成路由，从而简化了复杂繁冗的路由表查找和维护，节省了不必要的开销，提高了路由效率，实现了快速有效的数据传输。 为支持此路由协议本文提出了一种自适应动态地址分配算——ADAR（AdaptiveDynamicAddre...As one of the ten high technologies in the future, wireless sensor network, which is the integration of micro-sensors, embedded computing, modern network and Ad Hoc technologies, can apperceive, collect, process and transmit various information data within the region. It can be used in military defense, biomedical, environmental monitoring, disaster relief, counter-terrorism, remote control of haz...学位：工学硕士院系专业：信息科学与技术学院通信工程系_通信与信息系统学号：2332007115216

On the Resummed Gluon Anomalous Dimension and Structure Functions at Small

The impact of the recently evaluated `irreducible' contributions to the resummed next-to-leading logarithmic small-x anomalous dimension fl gg is evaluated for the unpolarized parton densities and structure functions of the nucleon. These new terms diminish the gluon distribution and are found to overcompensate the enhancement caused by the resummed leading logarithmic small-x anomalous dimension and the quarkonic contributions beyond next-to-leading order. PACS: 12.38.Cy, 13.60.Hb Phys. Rev. D57 (1998) The structure functions of the proton in unpolarized deep--inelastic scattering (DIS) show a steep rise towards very small Bjorken-x values, which becomes stronger with increasing resolution Q 2 . This behavior is a consequence both of the shape of the non-perturbative quark singlet and gluon initial distributions -- x\Sigma and xg rise roughly like x \Gamma0:2 for a starting scale Q 2 0 ' 4 GeV 2 -- and of the form of the evolution kernels governing the renormalization group e..

Higher Twist contributions to the Structure Functions F2(x,Q2)\mathrm{F_2(x,Q^2)} and g2(x,Q2)\mathrm{g_2(x,Q^2)}

We report on recent results on higher twist contributions to the unpolarized structure functions $F_2^{p,d}(x,Q^2)$ at N$^3$LO in the large $x$ region and constraints on the twist--3 contribution to polarized structure function $g_2(x,Q^2)$

Integral relations for twist -2 and twist - three contributions to polarized structure functions

We discuss the relations between the twist 2 and twist 3 contributions to polarized deep-inelastic scattering structure functions both for neutral and charged current interactions which are predicted by the operator product expansion in lowest order in QCD

Vector Leptoquark Pair Production in

The cross section for vector leptoquark pair production in e + e \Gamma annihilation is calculated for the case of finite anomalous gauge boson couplings fl;Z and fl;Z . The minimal cross section is found to behave / fi 7 , leading to weaker mass bounds in the threshold range than in models studied previously. Various extensions of the Standard Model predict bosonic states carrying both lepton and quark quantum numbers, the leptoquarks. If their couplings are baryon and lepton number conserving, cf. see [1], these states may even exist in the mass range accessible at high energy colliders. Stringent bounds on the leptoquark--fermion couplings lq are derived from low energy data [2]. In the mass range M V 1 TeV they are required to be much smaller than the electromagnetic coupling. On the other hand the bosonic leptoquark couplings cannot be arbitrarily small but are determined by the respective gauge couplings and eventual anomalous couplings. In this note we extend the ana..