On the power divergence in quasi gluon distribution function

Recent perturbative calculation of quasi gluon distribution function at one-loop level shows the existence of extra linear ultraviolet divergences in the cut-off scheme. We employ the auxiliary field approach, and study the renormalization of gluon operators. The non-local gluon operator can mix with new operators under renormalization, and the linear divergences in quasi distribution function can be into the newly introduced operators. After including the mixing, we find the improved quasi gluon distribution functions contain only logarithmic divergences, and thus can be used to extract the gluon distribution in large momentum effective theory.Comment: 18 pages, 10 figures. Published version in JHE

Paradigm and paradox in topology control of power grids

Corrective Transmission Switching can be used by the grid operator to relieve line overloading and voltage violations, improve system reliability, and reduce system losses. Power grid optimization by means of line switching is typically formulated as a mixed integer programming problem (MIP). Such problems are known to be computationally intractable, and accordingly, a number of heuristic approaches to grid topology reconfiguration have been proposed in the power systems literature. By means of some low order examples (3-bus systems), it is shown that within a reasonably large class of “greedy” heuristics, none can be found that perform better than the others across all grid topologies. Despite this cautionary tale, statistical evidence based on a large number of simulations using IEEE 118-bus systems indicates that among three heuristics, a globally greedy heuristic is the most computationally intensive, but has the best chance of reducing generation costs while enforcing N-1 connectivity. It is argued that, among all iterative methods, the locally optimal switches at each stage have a better chance in not only approximating a global optimal solution but also greatly limiting the number of lines that are switched.First author draf

Sequential Selection of Correlated Ads by POMDPs

Online advertising has become a key source of revenue for both web search engines and online publishers. For them, the ability of allocating right ads to right webpages is critical because any mismatched ads would not only harm web users' satisfactions but also lower the ad income. In this paper, we study how online publishers could optimally select ads to maximize their ad incomes over time. The conventional offline, content-based matching between webpages and ads is a fine start but cannot solve the problem completely because good matching does not necessarily lead to good payoff. Moreover, with the limited display impressions, we need to balance the need of selecting ads to learn true ad payoffs (exploration) with that of allocating ads to generate high immediate payoffs based on the current belief (exploitation). In this paper, we address the problem by employing Partially observable Markov decision processes (POMDPs) and discuss how to utilize the correlation of ads to improve the efficiency of the exploration and increase ad incomes in a long run. Our mathematical derivation shows that the belief states of correlated ads can be naturally updated using a formula similar to collaborative filtering. To test our model, a real world ad dataset from a major search engine is collected and categorized. Experimenting over the data, we provide an analyse of the effect of the underlying parameters, and demonstrate that our algorithms significantly outperform other strong baselines

Paradigm and Paradox in Topology Control of Power Grids

Corrective Transmission Switching can be used by the grid operator to relieve line overloading and voltage violations, improve system reliability, and reduce system losses. Power grid optimization by means of line switching is typically formulated as a mixed integer programming problem (MIP). Such problems are known to be computationally intractable, and accordingly, a number of heuristic approaches to grid topology reconfiguration have been proposed in the power systems literature. By means of some low order examples (3-bus systems), it is shown that within a reasonably large class of greedy heuristics, none can be found that perform better than the others across all grid topologies. Despite this cautionary tale, statistical evidence based on a large number of simulations using using IEEE 118- bus systems indicates that among three heuristics, a globally greedy heuristic is the most computationally intensive, but has the best chance of reducing generation costs while enforcing N-1 connectivity. It is argued that, among all iterative methods, the locally optimal switches at each stage have a better chance in not only approximating a global optimal solution but also greatly limiting the number of lines that are switched

Holographic model of hybrid and coexisting s-wave and p-wave Josephson junction

In this paper the holographic model for hybrid and coexisting s-wave and p-wave Josephson junction is constructed by a triplet charged scalar field coupled with a non-Abelian $SU(2)$ gauge fields in (3+1)-dimensional AdS spacetime. Depending on the value of chemical potential $\mu$, one can show that there are four types of junctions (s+p-N-s+p, s+p-N-s, s+p-N-p and s-N-p). We show that DC current of all the hybrid and coexisting s-wave and p-wave junctions is proportional to the sine of the phase difference across the junction. In addition, the maximum current and the total condensation decays with the width of junction exponentially, respectively. For s+p-N-s and s-N-p junction, the maximum current decreases with growing temperature. Moreover, we find that the maximum current increases with growing temperature for s+p-N-s+p and s+p-N-p junction, which is in the different manner as the behaviour of s+p-N-s and s-N-p junction.Comment: 20 pages, 12 figures, v2: typos corrected, references added, published versio

Poverty Management App and Hospital Text Platform

There are two parts of this honors research: designing an Android App for managing daily finances to avoid poverty, and a text platform for patients who have left a hospital after being admitted for a suicide attempt. The Android App is designed especially for poor people to help them manage daily income and living expenses. This app will contain a cover page, information input page, income and suggested spending plots, a suggestion page, as well as a user manual. Users have to input daily income, and desired wealth and daily expenses, then they will be given a suggestion page that contains the suggested living expenses which is calculated by a proportional-integral-derivative controller (PID controller). Furthermore, all information will be stored and the user can choose to plot these data for analysis. The integral and derivative parts of the PID controller will be treated as discrete functions and specified by previous inputs of the user. This app will be implemented by Phonegap, which is a mobile development framework, using web application technologies like HTML, CSS, JavaScript as well as Jquery. The data will be stored using LocalStorage, which is given by the PhoneGap API. The PID controller is implemented by JavaScript with local stored data and plot functions executed by jqPlot. The text platform for hospitals is designed for reminding patients about their appointments as well as psychological suggestions for patients to help prevent suicide. This platform will contain a log in system, which provides limited access to protect the security of the patients' information. The user (health care professional) can input specific messages and choose the patient to send the information to. This platform is a web application and implemented by HTML, CSS, JavaScript and Ruby on Rails. The function of sending SMS to cell phones is implemented by Rails mailer.No embargoAcademic Major: Electrical and Computer Engineerin

The supply-side structural reform of China in steel industry and outlooks

The objective of this thesis is to provide an overview of the supply-side structural reform (SSSR) of China’s steel industry, which was first proposed in 2015 and has been undertaken since. After providing the political and economic arguments used by China’s government in promoting the reform, the paper focuses specifically on the major concerns regarding the sector, current restructuring policies, remaining problems, and corresponding policy countermeasures. After scrutinizing the impacts of SSSR, and the pace of policy implementation, the paper addresses which outcomes are most likely in the foreseeable future

Thermal and photo-induced oxidation reaction on silicon and copper surfaces

Ph.DDOCTOR OF PHILOSOPH