Physical Sciences and Mathematics Commons^™

Implementimi I Sherbimeve Te Kualitetit (Qos) Ne Ndermarrjet E Vogla Dhe Te Mesme, Kushtrim Berisha

Theses and Dissertations

Në ndërmarrjet e vogla apo të mesme shpesh bie nevoja që kualiteti i shërbimeve të jetë pikë kritike për shumë arsye si p.sh. Ofrimi i shërbimeve online për konsumatorin në kohë reale dhe efikasitet të lartë, si dhe parandalime të vonesave të mundshme në rrjetë për arsye të kapacitetit të bandwidth-it apo resurseve teknike.

Si fillim nevoja për shërbime të kualitetit është shfaqur në voice (telephony) në vitin 1994 nga organizata për standardizime të teknologjisë informative ITU [1]. Më vonë shërbimet e kualiteti u bënë të nevojshme edhe në shërbime dhe servise të tjera siç janë: response time, loss, crosstalk …

Fast Optimal Aggregate Point Search For A Merged Set On Road Networks, Weiwei Sun, Chong Chen, Baihua Zheng, Chunan Chen, Liang Zhu, Weimo Liu, Yan Huang

Research Collection School Of Computing and Information Systems

Aggregate nearest neighbor query, which returns an optimal target point that minimizes the aggregate distance for a given query point set, is one of the most important operations in spatial databases and their application domains. This paper addresses the problem of finding the aggregate nearest neighbor for a merged set that consists of the given query point set and multiple points needed to be selected from a candidate set, which we name as merged aggregate nearest neighbor(MANN) query. This paper proposes two algorithms to process MANN query on road networks when aggregate function is max. Then, we extend the algorithms …

A Comparative Study Between Motivated Learning And Reinforcement Learning, James T. Graham, Janusz A. Starzyk, Zhen Ni, Haibo He, T.-H. Teng, Ah-Hwee Tan

Research Collection School Of Computing and Information Systems

This paper analyzes advanced reinforcement learning techniques and compares some of them to motivated learning. Motivated learning is briefly discussed indicating its relation to reinforcement learning. A black box scenario for comparative analysis of learning efficiency in autonomous agents is developed and described. This is used to analyze selected algorithms. Reported results demonstrate that in the selected category of problems, motivated learning outperformed all reinforcement learning algorithms we compared with.

An Adaptive Computational Model For Personalized Persuasion, Yilin Kang, Ah-Hwee Tan, Chunyan Miao

Research Collection School Of Computing and Information Systems

While a variety of persuasion agents have been created and applied in different domains such as marketing, military training and health industry, there is a lack of a model which can provide a unified framework for different persuasion strategies. Specifically, persuasion is not adaptable to the individuals’ personal states in different situations. Grounded in the Elaboration Likelihood Model (ELM), this paper presents a computational model called Model for Adaptive Persuasion (MAP) for virtual agents. MAP is a semi-connected network model which enables an agent to adapt its persuasion strategies through feedback. We have implemented and evaluated a MAP-based virtual nurse …

A New Public Remote Integrity Checking Scheme With User Privacy, Yiteng Feng, Yi Mu, Guomin Yang, Joseph Liu

Research Collection School Of Computing and Information Systems

With a cloud storage, users can store their data files on a remote cloud server with a high quality on-demand cloud service and are able to share their data with other users. Since cloud servers are not usually regarded as fully trusted and the cloud data can be shared amongst users, the integrity checking of the remote files has become an important issue. A number of remote data integrity checking protocols have been proposed in the literature to allow public auditing of cloud data by a third party auditor (TPA). However, user privacy is not taken into account in most …

Production Cost Heterogeneity In A Circular-City Model, Mei Lin, Ruhai Wu

Research Collection School Of Computing and Information Systems

We derive the closed-form solution characterizing the equilibrium in a circular-city model with competing firms of heterogeneous production costs. Tractability issues in this setting are well known and have not been resolved in prior work. In this paper, the equilibrium solution illustrates effects of production costs on firms’ strategic decisions, their aggregate profit, and consumer surplus.

Privacy-Preserving Offloading Of Mobile App To The Public Cloud, Yue Duan, Mu Zhang, Heng Yin, Yuzhe Tang

Research Collection School Of Computing and Information Systems

To support intensive computations on resource-restricting mobile devices, studies have been made to enable the offloading of a part of a mobile program to the cloud. However, none of the existing approaches considers user privacy when transmitting code and data off the device, resulting in potential privacy breach. In this paper, we present the design and implementation of a system that automatically performs fine-grained privacy-preserving Android app offloading. It utilizes static analysis and bytecode instrumentation techniques to ensure transparent and efficient Android app offloading while preserving user privacy. We evaluate the effectiveness and performance of our system using two Android …

Personalized Sentiment Classification Based On Latent Individuality Of Microblog Users, Kaisong Song, Shi Feng, Wei Gao, Daling Wang, Ge Yu, Kam-Fai Wong

Research Collection School Of Computing and Information Systems

Sentiment expression in microblog posts often reflects user’s specific individuality due to different language habit, personal character, opinion bias and so on. Existing sentiment classification algorithms largely ignore such latent personal distinctions among different microblog users. Meanwhile, sentiment data of microblogs are sparse for individual users, making it infeasible to learn effective personalized classifier. In this paper, we propose a novel, extensible personalized sentiment classification method based on a variant of latent factor model to capture personal sentiment variations by mapping users and posts into a low-dimensional factor space. We alleviate the sparsity of personal texts by decomposing the posts …

A New General Framework For Secure Public Key Encryption With Keyword Search, Rongmao Chen, Yi Mu, Guomin Yang, Fuchun Guo, Xiaofen Wang

Research Collection School Of Computing and Information Systems

Public Key Encryption with Keyword Search (PEKS), introduced by Boneh et al. in Eurocrypt’04, allows users to search encrypted documents on an untrusted server without revealing any information. This notion is very useful in many applications and has attracted a lot of attention by the cryptographic research community. However, one limitation of all the existing PEKS schemes is that they cannot resist the Keyword Guessing Attack (KGA) launched by a malicious server. In this paper, we propose a new PEKS framework named Dual-Server Public Key Encryption with Keyword Search (DS-PEKS). This new framework can withstand all the attacks, including the …

S-Looper: Automatic Summarization For Multipath String Loops, Xiaofei Xie, Yang Liu, Wei Le, Xiaohong Li, Hongxu Chen

Research Collection School Of Computing and Information Systems

Loops are important yet most challenging program constructs to analyze for various program analysis tasks. Existing loop analysis techniques mainly handle well loops that contain only integer variables with a single path in the loop body. The key challenge in summarizing a multiple-path loop is that a loop traversal can yield a large number of possibilities due to the different execution orders of these paths located in the loop; when a loop contains a conditional branch related to string content, we potentially need to track every character in the string for loop summarization, which is expensive. In this paper, we …

Towards A Global Model Of Spin-Orbit Coupling In The Halocarbenes, Silver Nyambo, Cyrus Karshenas, Scott Reid, Phalgun Lolur, Richard Dawes

Chemistry Faculty Research and Publications

We report a global analysis of spin-orbit coupling in the mono-halocarbenes, CH(D)X, where X = Cl, Br, and I. These are model systems for examining carbene singlet-triplet energy gaps and spin-orbit coupling. Over the past decade, rich data sets collected using single vibronic level emission spectroscopy and stimulated emission pumping spectroscopy have yielded much information on the ground vibrational level structure and clearly demonstrated the presence of perturbations involving the low-lying triplet state. To model these interactions globally, we compare two approaches. First, we employ a diabatic treatment of the spin-orbit coupling, where the coupling matrix elements are written in …

Interdisciplinary Modeling For Water-Related Issues Graduate Course, Laurel Saito, Alexander Fernald, Timothy Link

All ECSTATIC Materials

The science and management of aquatic ecosystems is inherently interdisciplinary, with issues associated with hydrology, atmospheric science, water quality, geochemistry, sociology, economics, environmental science, and ecology. Addressing water resources issues in any one discipline invariably involves effects that concern other disciplines, and attempts to address one issue often have consequences that exacerbate existing issues or concerns, or create new ones (Jørgensen et al. 1992; Lackey et al. 1975; Straskraba 1994) due to the strongly interactive nature of key processes (Christensen et al. 1996). Thus, research and management of aquatic ecosystems must be interdisciplinary to be most effective, but such truly …

Geometrization Conditions For Perfect Fluids, Scalar Fields, And Electromagnetic Fields, Charles G. Torre, Dionisios Krongos

All Physics Faculty Publications

Rainich-type conditions giving a spacetime “geometrization” of matter fields in general relativity are reviewed and extended. Three types of matter are considered: perfect fluids, scalar fields, and elec- tromagnetic fields. Necessary and sufficient conditions on a spacetime metric for it to be part of a perfect fluid solution of the Einstein equa- tions are given. Formulas for constructing the fluid from the metric are obtained. All fluid results hold for any spacetime dimension. Ge- ometric conditions on a metric which are necessary and sufficient for it to define a solution of the Einstein-scalar field equations and for- mulas for constructing …

Forecasting The Response Of Earth's Surface To Future Climatic And Land Use Changes: A Review Of Methods And Research Needs, Jon D. Pelletier, A. Brad Murray, Jennifer L. Pierce, Paul R. Bierman, David D. Breshears, Benjamin T. Crosby, Michael Ellis, Efi Foufoula-Georgiou, Arjun M. Heimsath, Chris Houser, Nick Lancaster, Marco Marani, Dorothy J. Merritts, Laura J. Moore, Joel Pederson, Michael J. Poulos, Tammy M. Rittenour, Joel C. Rowland, Peter Ruggiero, Dylan J. Ward, Andrew D. Wickert, Elowyn M. Yager

Geosciences Faculty Publications

In the future, Earth will be warmer, precipitation events will be more extreme, global mean sea level will rise, and many arid and semiarid regions will be drier. Human modifications of landscapes will also occur at an accelerated rate as developed areas increase in size and population density. We now have gridded global forecasts, being continually improved, of the climatic and land use changes (C&LUC) that are likely to occur in the coming decades. However, besides a few exceptions, consensus forecasts do not exist for how these C&LUC will likely impact Earth-surface processes and hazards. In some cases, we have …

Mexico City Normal Weight Children Exposed To High Concentrations Of Ambient Pm2.5 Show High Blood Leptin And Endothelin-1, Vitamin D Deficiency, And Food Reward Hormone Dysregulation Versus Low Pollution Controls. Relevance For Obesity And Alzheimer Disease, Partha S. Mukherjee

Mathematics Faculty Publications and Presentations

Millions of Mexico, US and across the world children are overweight and obese. Exposure to fossil-fuel combustion sources increases the risk for obesity and diabetes, while long-term exposure to fine particulate matter (PM _2.5) and ozone (O₃) above US EPA standards is associated with increased risk of Alzheimer’s disease (AD). Mexico City Metropolitan Area children are chronically exposed to PM_2.5 and O₃ concentrations above the standards and exhibit systemic, brain and intrathecal inflammation, cognitive deficits, and Alzheimer disease neuropathology. We investigated adipokines, food reward hormones, endothelial dysfunction, vitamin D and apolipoprotein E (APOE) relationships in …

A Lego® Brewster Angle Microscope For Quantitative Monolayer Film Analysis, Nicholas Benz

Physics

In order to study single-molecule thick films and their phase behavior we built a Brewster Angle Microscope (BAM). BAM’s are inherently expensive due to their accuracy and precision. We built a fully functional BAM using Lego® Mindstorm® kits for the fraction of the price of a commercial BAM. And by utilizing the 10µm patented Lego® tolerance, comparable accuracy was attained. The BAM was mounted to a Langmuir-trough and will be used for laboratory experiments for optics and physical chemistry along with research on lung surfactant and on liquid crystals.

Geometrization Conditions For Perfect Fluids, Scalar Fields, And Electromagnetic Fields, Charles G. Torre, Dionisios Krongos

Charles G. Torre

Rainich-type conditions giving a spacetime “geometrization” of matter fields in general relativity are reviewed and extended. Three types of matter are considered: perfect fluids, scalar fields, and electromagnetic fields. Necessary and sufficient conditions on a spacetime metric for it to be part of a perfect fluid solution of the Einstein equations are given. Formulas for constructing the fluid from the metric are obtained. All fluid results hold for any spacetime dimension. Geometric conditions on a metric which are necessary and sufficient for it to define a solution of the Einstein-scalar field equations and formulas for constructing the scalar field from …

Log-Euclidean Metric Learning On Symmetric Positive Definite Manifold With Application To Image Set Classification, Zhiwu Huang, R. Wang, S. Shan, X. Li, X. Chen

Research Collection School Of Computing and Information Systems

The manifold of Symmetric Positive Definite (SPD) matrices has been successfully used for data representation in image set classification. By endowing the SPD manifold with Log-Euclidean Metric, existing methods typically work on vector-forms of SPD matrix logarithms. This however not only inevitably distorts the geometrical structure of the space of SPD matrix logarithms but also brings low efficiency especially when the dimensionality of SPD matrix is high. To overcome this limitation, we propose a novel metric learning approach to work directly on logarithms of SPD matrices. Specifically, our method aims to learn a tangent map that can directly transform the …

Message Passing For Collective Graphical Models, Tao Sun, Daniel Sheldon, Akshat Kumar

Research Collection School Of Computing and Information Systems

Collective graphical models (CGMs) are a formalism for inference and learning about a population of independent and identically distributed individuals when only noisy aggregate data are available. We highlight a close connection between approximate MAP inference in CGMs and marginal inference in standard graphical models. The connection leads us to derive a novel Belief Propagation (BP) style algorithm for collective graphical models. Mathematically, the algorithm is a strict generalization of BP—it can be viewed as an extension to minimize the Bethe free energy plus additional energy terms that are non-linear functions of the marginals. For CGMs, the algorithm is much …

Estimating Effectiveness Of Twitter Messages With A Personalized Machine Learning Approach, Xunhu Sun

Theses and Dissertations

In Twitter, many aspects of retweeting behavior, which is the most effective indicator of spreading effectiveness of the tweet, have been researched, such as whether a reader will retweet a certain tweet or not. However, the total number of retweets of the tweet, which is the quantitative measure of quality, has not been well addressed by existing work. To estimate the number of retweets and associated factors, this paper proposes a procedure to develop a personalized model for one author. The training data comes from the author’s past tweets. We propose 3 types of new features based on the contents …

Optimizing Selection Of Competing Features Via Feedback-Directed Evolutionary Algorithms, Tian Huat Tan, Yinxing Xue, Manman Chen, Jun Sun, Yang Liu, Jin Song Dong Dong

Research Collection School Of Computing and Information Systems

Software that support various groups of customers usually require complicated configurations to attain different functionalities. To model the configuration options, feature model is proposed to capture the commonalities and competing variabilities of the product variants in software family or Software Product Line (SPL). A key challenge for deriving a new product is to find a set of features that do not have inconsistencies or conflicts, yet optimize multiple objectives (e.g., minimizing cost and maximizing number of features), which are often competing with each other. Existing works have attempted to make use of evolutionary algorithms (EAs) to address this problem. In …

Reliability Assessment For Distributed Systems Via Communication Abstraction And Refinement, Lin Gui, Jun Sun, Yang Liu, Jin Song Dong

Research Collection School Of Computing and Information Systems

Distributed systems like cloud-based services are ever more popular. Assessing the reliability of distributed systems is highly non-trivial. Particularly, the order of executions among distributed components adds a dimension of non-determinism, which invalidates existing reliability assessment methods based on Markov chains. Probabilistic model checking based on models like Markov decision processes is designed to deal with scenarios involving both probabilistic behavior (e.g., reliabilities of system components) and non-determinism. However, its application is currently limited by state space explosion, which makes reliability assessment of distributed system particularly difficult. In this work, we improve the probabilistic model checking through a method of …

Iowa Academy Of Science: The New Bulletin, V11n2, Summer 2015, Iowa Academy Of Science

New Bulletin

Table of Contents

Journal of the Iowa Academy of Science --- 1, 3
ICTM-ISTS Math Science Conference --- 2, 3
ISTS Pre-conference Event --- 3
IAS Education Programs --- 4, 5
National Congress on Science Education --- 6
128th IAS Annual Meeting --- 7
New Horizon's Flyby --- 7
Corporate Members --- 7
Contact IAS --- 8
Institutional Members --- 8

Why Linear (And Piecewise Linear) Models Often Successfully Describe Complex Non-Linear Economic And Financial Phenomena: A Fuzzy-Based Explanation, Hung T. Nguyen, Vladik Kreinovich, Olga Kosheleva, Songsak Sriboonchitta

Departmental Technical Reports (CS)

Economic and financial phenomena are highly complex and non-linear. However, surprisingly, in many cases, these phenomena are accurately described by linear models -- or, sometimes, by piecewise linear ones. In this paper, we show that fuzzy techniques can explain the unexpected efficiency of linear and piecewise linear models: namely, we show that a natural fuzzy-based precisiation of imprecise ("fuzzy") expert knowledge often leads to linear and piecewise linear models.

We also discuss which expert-motivated nonlinear models should be used to get a more accurate description of economic and financial phenomena.

Toric Partial Orders, Mike Develin, Matthew Macauley, Victor Reiner

Publications

We define toric partial orders, corresponding to regions of graphic toric hyperplane arrangements, just as ordinary partial orders correspond to regions of graphic hyperplane arrangements. Combinatorially, toric posets correspond to finite posets under the equivalence relation generated by converting minimal elements into maximal elements, or sources into sinks. We derive toric analogues for several features of ordinary partial orders, such as chains, antichains, transitivity, Hasse diagrams, linear extensions, and total orders.

Erratum: Low-Energy Electron-Impact Ionization Of Argon: Three-Dimensional Cross Section (Physical Review A - Atomic, Molecular, And Optical Physics 85, 032702 (2012)), Xueguang Ren, Thomas Pfluger, Joachim Hermann Ullrich, Oleg I. Zatsarinny, Klaus Bartschat, Don H. Madison, Alexander Dorn

Physics Faculty Research & Creative Works

No abstract provided.

Applicability Of The Position-Dependent Diffusion Approach To Localized Transport Through Disordered Waveguides, Pauf Neupane, Alexey Yamilov

Physics Faculty Research & Creative Works

In this work we show analytically and numerically that the localized regime of wave transport can be modeled as position-dependent diffusion with a diffusion coefficient that retains the memory of the source location. The dependence on the source diminishes when absorption is introduced.

Gottlieb Groups Of Function Spaces, Gregory Lupton, Samuel Bruce Smith

Mathematics and Statistics Faculty Publications

We analyze the Gottlieb groups of function spaces. Our results lead to explicit decompositions of the Gottlieb groups of many function spaces map(X,Y)---including the (iterated) free loop space of Y---directly in terms of the Gottlieb groups of Y. More generally, we give explicit decompositions of the generalized Gottlieb groups of map(X,Y) directly in terms of generalized Gottlieb groups of Y. Particular cases of our results relate to the torus homotopy groups of Fox. We draw some consequences for the classification of T-spaces and G-spaces. For X, Y finite and Y simply connected, we give a formula for the ranks of …

Size And Power Of Tests Of Hypotheses On Survival Parameters From The Lindley Distribution With Covariates, Macaulay Okwuokenye, Karl E. Peace

Biostatistics Faculty Publications

The Lindley model is considered as an alternative model facilitating analyses of time-to-event data with covariates. Covariate information is incorporated using the Cox’s proportional hazard model with the Lindley model at the timedependent component. Simulation studies are performed to assess the size and power of tests of hypotheses on parameters arising from maximum likelihood estimators of parameters in the Lindley model. Results are contrasted with that arising from Cox’s partial maximum likelihood estimator. The Linley model is used to analyze a publicly available data set and contrasted with other models.

Kelt-7b: A Hot Jupiter Transiting A Bright V = 8.54 Rapidly Rotating F-Star, A. Bieryla, K. Collins, T. G. Beatty, J. Eastman, R. J. Siverd, J. Pepper, B. S. Gaudi, K. G. Stassun, C. Cañas, D. W. Latham, L. A. Buchhave, R. Sanchis-Ojeda, J. N. Winn, Eric L.N. Jensen, J. F. Kielkopf, K. K. Mcleod, J. Gregorio, K. D. Colón, R. Street, R. Ross, M. Penny, S. N. Mellon, T. E. Oberst, B. J. Fulton, J. Wang, P. Berlind, M. L. Calkins, G. A. Esquerdo, D. L. Depoy, A. Gould, J. Marshall, R. Pogge, M. Trueblood, P. Trueblood

Physics & Astronomy Faculty Works

We report the discovery of KELT-7b, a transiting hot Jupiter with a mass of 1.28+/- 0.18 M_J, radius of {1.533}_-0.047^+0.046 R_J, and an orbital period of 2.7347749+/- 0.0000039 days. The bright host star (HD 33643; KELT-7) is an F-star with V = 8.54, T_eff = 6789{}_-49⁺⁵⁰ K, [Fe/H] = {0.139}_-0.081^+0.075, and {log}\{\text{}}g\=4.149+/- 0.019. It has a mass of {1.535}_-0.054^+0.066 M_☉, a radius of {1.732}_-0.045^+0.043 R_☉, and is the fifth most massive, fifth hottest, and the ninth brightest star known to …