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Cybercrime Deterrence And International Legislation: Evidence From Distributed Denial Of Service Attacks, Kai-Lung HUI, Seung Hyun KIM, QIU-HONG WANG 2017 Singapore Management University

Cybercrime Deterrence And International Legislation: Evidence From Distributed Denial Of Service Attacks, Kai-Lung Hui, Seung Hyun Kim, Qiu-Hong Wang

Research Collection School Of Information Systems

In this paper, we estimate the impact of enforcing the Convention on Cybercrime (COC) on deterring distributed denial of service (DDOS) attacks. Our data set comprises a sample of real, random spoof-source DDOS attacks recorded in 106 countries in 177 days in the period 2004-2008. We find that enforcing the COC decreases DDOS attacks by at least 11.8 percent, but a similar deterrence effect does not exist if the enforcing countries make a reservation on international cooperation. We also find evidence of network and displacement effects in COC enforcement. Our findings imply attackers in cyberspace are rational, motivated by ...


Compact Dual-Band Bandpass Filter Based On Fractal Stub-Loaded Resonator, Hadi T. Ziboon, Jawad K. Ali 2017 Department of Electrical Engineering, University of Technology, Iraq

Compact Dual-Band Bandpass Filter Based On Fractal Stub-Loaded Resonator, Hadi T. Ziboon, Jawad K. Ali

Professor Jawad K. Ali

Fractal geometries have shown to be a suitable choice for the antenna and microwave circuit designers to produce compact size microwave devices and components. Moreover, the multimode resonators are found advantageous in the design of reduced size multiband bandpass filters. In this paper, a stub loaded resonator (SLR) based on modified Minkowski fractal geometry, is suggested to produce a compact microstrip bandpass filter with dual-band response for wireless communication applications. Based on the second iteration Minkowski fractal geometry, dual-band compact microstrip BPF has been presented. The proposed filter structure is composed of two fractal based symmetrical SLRs. The filter structure ...


Compact Dual-Mode Microstrip Band Reject Filter Based On Koch Fractal Geometry, Hayder S. Ahmed, Ali J. Salim, Jawad K. Ali 2017 Department of Electrical, University of Technology, Iraq

Compact Dual-Mode Microstrip Band Reject Filter Based On Koch Fractal Geometry, Hayder S. Ahmed, Ali J. Salim, Jawad K. Ali

Professor Jawad K. Ali

In this paper, a new fractal-based microstrip dual-mode band stop filter (BSF) has been
presented. The proposed filter structure is mainly based on that of the triangular patch resonators
with an embedded slit structure. The Koch fractal geometry has been applied to the uncoupled side
lengths of the triangular patch resonator. The filter structure has been modeled, and its performance
is evaluated using the commercially available EM simulator, Sonnet. Results reveal that the
resulting dual-mode response depends heavily on the uncoupled side lengths of the triangular patch
resonator. A parametric study has been conducted to explore the effect of the ...


A Compact Dual-Band Slot Antenna Based On Koch Fractal Snowflake Annular Ring, Mahmood T. Yassen, Mohammed R. Hussan, Hussain A. Hammas, Hussam Al-Saedi, Jawad K. Ali 2017 Department of Electrical Engineering, University of Technology, Iraq

A Compact Dual-Band Slot Antenna Based On Koch Fractal Snowflake Annular Ring, Mahmood T. Yassen, Mohammed R. Hussan, Hussain A. Hammas, Hussam Al-Saedi, Jawad K. Ali

Professor Jawad K. Ali

This paper presents the design of a compact dual-band slot antenna for use in the
recently available wireless communication applications. The slot structure of the proposed antenna
is based on an annular slot-ring with Koch snowflake fractal geometry of the third iteration. The
antenna slot structure has been etched on the ground plane of a substrate with relative permittivity
of 4.5 and 1.524 mm thickness. On the other side of the substrate, a 50-Ohm microstrip line has
been etched as the antenna feed structure. The proposed antenna has a compact size of (40 × 40 ×
1.524) mm3. Simulation ...


Roman Domination In Complementary Prisms, Alawi I. Alhashim 2017 East Tennessee State University

Roman Domination In Complementary Prisms, Alawi I. Alhashim

Electronic Theses and Dissertations

The complementary prism GG of a graph G is formed from the disjoint union of G and its complement G by adding the edges of a perfect match- ing between the corresponding vertices of G and G. A Roman dominating function on a graph G = (V,E) is a labeling f : V(G) → {0,1,2} such that every vertex with label 0 is adjacent to a vertex with label 2. The Roman domination number γR(G) of G is the minimum f(V ) = Σv∈V f(v) over all such functions of G. We study the Roman domination number ...


Synthesis And In-Vitro Cell Viability/Cytotoxicity Studies Of Novel Pyrrolobenzodiazepine Derivatives, John M. Jarrett 2017 East Tennessee State University

Synthesis And In-Vitro Cell Viability/Cytotoxicity Studies Of Novel Pyrrolobenzodiazepine Derivatives, John M. Jarrett

Undergraduate Honors Theses

Pyrrolobenzodiazepines (PBDs) are a group of naturally occurring compounds that were discovered in the cultures of Streptomyces in the 1960s. Some natural PBDs discovered in these cultures, such as anthramycin and sibiromycin, were shown to possess a broad spectrum of anti-tumor activity. Since cancer is still a leading cause of death globally, the development of novel anti-proliferative derivatives of PBDs is essential for human welfare worldwide. Further synthesis and structure-activity relationship (SAR) studies of the parent natural products and their tetracyclic analogs will lead to the discovery of drug candidates. In this work, thirteen PBD analogues were synthesized using no ...


Sustainability Education In Primary And Secondary Schools: Great Needs And Possible Solutions, Allison Watson 2017 University of Tennessee, Knoxville

Sustainability Education In Primary And Secondary Schools: Great Needs And Possible Solutions, Allison Watson

University of Tennessee Honors Thesis Projects

No abstract provided.


Effect Of Chain Rigidity On Network Architecture And Deformation Behavior Of Glassy Polymer Networks, Kyler Reser Knowles 2017 University of Southern Mississippi

Effect Of Chain Rigidity On Network Architecture And Deformation Behavior Of Glassy Polymer Networks, Kyler Reser Knowles

Dissertations

Processing carbon fiber composite laminates creates molecular-level strains in the thermoset matrix upon curing and cooling which can lead to failures such as geometry deformations, micro-cracking, and other issues. It is known strain creation is attributed to the significant volume and physical state changes undergone by the polymer matrix throughout the curing process, though storage and relaxation of cure-induced strains remain poorly understood. This dissertation establishes two approaches to address the issue. The first establishes testing methods to simultaneously measure key volumetric properties of a carbon fiber composite laminate and its polymer matrix. The second approach considers the rigidity of ...


Recommender Response To Diversity And Popularity Bias In User Profiles, Sushma Channamsetty, Michael D. Ekstrand 2017 Boise State University

Recommender Response To Diversity And Popularity Bias In User Profiles, Sushma Channamsetty, Michael D. Ekstrand

Michael D. Ekstrand

Recommender system evaluation usually focuses on the overall effectiveness of the algorithms, either in terms of measurable accuracy or ability to deliver user satisfaction or improve business metrics. When additional factors are considered, such as the diversity or novelty of the recommendations, the focus typically remains on the algorithm’s overall performance. We examine the relationship of the recommender’s output characteristics – accuracy, popularity (as an inverse of novelty), and diversity – to characteristics of the user’s rating profile. The aims of this analysis are twofold: (1) to probe the conditions under which common algorithms produce more or less diverse ...


Dynamic Secondary Electron Emission In Dielectric/Conductor Mixed Coatings, Leandro Olano, Isabel Montero, María E. Dávila, JR Dennison 2017 Instituto de Ciencia de Materiales de Madrid

Dynamic Secondary Electron Emission In Dielectric/Conductor Mixed Coatings, Leandro Olano, Isabel Montero, María E. Dávila, Jr Dennison

Presentations

An unexpected behavior of the Secondary Emission Yield (SEY) on coatings composed by a mixture of conductor and dielectric microparticles was reported and modeled in [1]. As a follow up, we measured for a fixed primary energy the dynamic evolution of the SEY in similar samples and proposed a charging-roughness coupled model to simulate the experimental results. Two different coatings were selected: 1) TMM and Al microparticles (type 1), and 2) zeolites and gold nanoparticles (type 2). Pulsed and continuous tests were used to obtain the SEY as a function of the primary energy.

In both types of samples extremely ...


Diverse Stellar Haloes In Nearby Milky Way Mass Disc Galaxies., Benjamin Harmsen, Antonela Monachesi, Eric F. Bell, Roelof S. de Jong, Jeremy Bailin, David J. Radburn-Smith, Benne W. Holwerda 2017 University of Michigan-Ann Arbor

Diverse Stellar Haloes In Nearby Milky Way Mass Disc Galaxies., Benjamin Harmsen, Antonela Monachesi, Eric F. Bell, Roelof S. De Jong, Jeremy Bailin, David J. Radburn-Smith, Benne W. Holwerda

Faculty Scholarship

We have examined the resolved stellar populations at large galactocentric distances along the minor axis (from 10 kpc up to between 40 and 75 kpc), with limited major axis coverage, of six nearby highly inclined MilkyWay (MW) mass disc galaxies using Hubble Space Telescope data from the Galaxy haloes, Outer discs, Substructure, Thick discs, and Star clusters (GHOSTS) survey. We select red giant branch stars to derive stellar halo density profiles. The projected minor axis density profiles can be approximated by power laws with projected slopes of −2 to −3.7 and a diversity of stellar halo masses of 1 ...


Automatic Verification Of Finite Precision Implementations Of Linear Controllers, Junkil Park, Miroslav Pajic, Oleg Sokolsky, Insup Lee 2017 University of Pennsylvania

Automatic Verification Of Finite Precision Implementations Of Linear Controllers, Junkil Park, Miroslav Pajic, Oleg Sokolsky, Insup Lee

Departmental Papers (CIS)

We consider the problem of verifying finite precision implementation of linear time-invariant controllers against mathematical specifications. A specification may have multiple correct implementations which are different from each other in controller state representation, but equivalent from a perspective of input-output behavior (e.g., due to optimization in a code generator). The implementations may use finite precision computations (e.g. floating-point arithmetic) which cause quantization (i.e., roundoff) errors. To address these challenges, we first extract a controller's mathematical model from the implementation via symbolic execution and floating-point error analysis, and then check approximate input-output equivalence between the extracted model ...


Implementing Propensity Score Matching With Network Data: The Effect Of Gatt On Bilateral Trade, Luca De Benedictis, Bruno Arpino, Alessandra Mattei 2017 Universitat Pompeu Fabra

Implementing Propensity Score Matching With Network Data: The Effect Of Gatt On Bilateral Trade, Luca De Benedictis, Bruno Arpino, Alessandra Mattei

Luca De Benedictis

Motivated by the evaluation of the causal effect of the General Agreement on Tariffs and Trade on bilateral international trade flows, we investigate the role of network structure in propensity score matching under the assumption of strong ignorability. We study the sensitivity of causal inference with respect to the presence of characteristics of the network in the set of confounders conditional on which strong ignorability is assumed to hold. We find that estimates of the average causal effect are highly sensitive to the presence of node-level network statistics in the set of confounders. Therefore, we argue that estimates may suffer ...


A New Physical Model For Dc Partial Discharge In Polymeric Insulators, Allen Andersen, JR Dennison 2017 Utah State University

A New Physical Model For Dc Partial Discharge In Polymeric Insulators, Allen Andersen, Jr Dennison

Presentations

The physics of DC partial discharge (DCPD) continues to pose a challenge to researchers. We present a new physically-motivated model of DCPD in amorphous polymers based on our dual-defect model of dielectric breakdown. The dual-defect model is an extension of standard static mean field theories, such as the Crine model, that describe avalanche breakdown of charge carriers trapped on uniformly distributed defect sites. It assumes the presence of both high-energy chemical defects and low-energy thermally-recoverable physical defects. We present our measurements of breakdown and DCPD for several common polymeric materials in the context of this model. Improved understanding of DCPD ...


Model For Charge Injection With Electron Beams Into Highly Disordered Insulating Materials, JR Dennison 2017 Utah State Univesity

Model For Charge Injection With Electron Beams Into Highly Disordered Insulating Materials, Jr Dennison

Presentations

The Walden-Wintle model for charge injection and transport through highly disordered insulating materials has been extended to include charge injection with a charged particle beam. The original model is applicable to charge injection into a dielectric material from a pair of electrodes in a parallel-plate geometry. It provides a versatile approach to predict the time-dependent current at a rear grounded electrode and the incident surface voltage, as the injection current density evolves over time with the development of a space charge barrier near the injection electrode. The Walden-Wintle model has been applied to many standard cases including Fowler-Nordheim injection, Schottky ...


Session E-1: Sharing Analogies And Demonstrations To Reinforce Chemistry Concepts, Dave DeVol, Angela Ahrendt 2017 Illinois Mathematics and Science Academy

Session E-1: Sharing Analogies And Demonstrations To Reinforce Chemistry Concepts, Dave Devol, Angela Ahrendt

Professional Learning Day

Chemistry concepts can often be difficult for students to understand, in part due to the fact that we are discussing with students things that cannot be seen (atoms and molecules!). Analogies that relate chemistry concepts to things that students are more familiar with can be a powerful way to help them understand concepts, as can demonstrations that make concepts come to life visually. We will share a few of our favorite analogies/demos, and ask that each participant share one of their favorite analogies or demos. As we realize it would be difficult for visiting teachers to bring what they ...


Session D-1: Lies, Damn Lies, And Statistics, Peter Dong, Joseph Traina 2017 Illinois Mathematics and Science Academy

Session D-1: Lies, Damn Lies, And Statistics, Peter Dong, Joseph Traina

Professional Learning Day

The crucial and sometimes difficult areas of data analysis and statistics can be made clearer by looking at examples of how they can be done badly - examples which, unfortunately, are easy to find. We share our experience teaching a short course which examines disingenuous graphs, biased surveys, deliberately misworded statements, and other methods of misrepresenting data. The negative examples provide an opportunity to discuss how statistics should properly be done, and explain what can happen when statistics are used incorrectly. We include a discussion of the failure of polls to predict the outcome of the presidential election.


Session C-1: Modeling Stem Activities Into Classroom Practice, Sowmya Anjur 2017 Illinois Mathematics and Science Academy

Session C-1: Modeling Stem Activities Into Classroom Practice, Sowmya Anjur

Professional Learning Day

Students understand concepts better when they have had a chance to work hands on with relevant material. Examples will be presented from my classroom where difficult concepts have been modeled into simple experiments with considerable success in enhancing student understanding. Special focus will be given to selected topics that students seem to have the most difficulty grasping. The objective is to enable students to transfer their understanding to solve complex problems with considerable ease and apply their understanding to real world scenarios on assessments. Suggestions will also be provided for implementation of various concepts into the high school classroom.


Session A-3: Three-Act Math Tasks, Lindsey Herlehy 2017 Illinois Mathematics and Science Academy

Session A-3: Three-Act Math Tasks, Lindsey Herlehy

Professional Learning Day

Participants will engage in a Three-Act Math task highlighting the application of properties of geometrical figures. Developed by Dan Meyer, an innovative and highly regarded mathematics instructor, Three-Act Math tasks utilize pedagogical skills that elicit student curiosity, collaboration and questioning. By posing a mathematical problem through active storytelling, this instructional approach redefines real-world mathematics and clarifies the role that a student plays in the learning process. Participants will be given multiple resources where they can access Three-Act Math tasks appropriate for upper elementary grades through Algebra and Geometry courses.


Session A-1: Bca Method, Focusing On Mole Ratios In Stoichiometry, Carmela Jones, Deb Scarano, Anita White 2017 Illinois Mathematics and Science Academy

Session A-1: Bca Method, Focusing On Mole Ratios In Stoichiometry, Carmela Jones, Deb Scarano, Anita White

Professional Learning Day

Traditionally stoichiometry is done using dimensional analysis. Although effective, it is confusing, messy, and does not focus on mole ratios. On the other hand, the BCA method (Before-Change-After), is clear, clean, and highlights the mole ratios in a chemical reaction. Participants will collect mass data in an experiment and learn how to use a BCA table. Teachers will bring the BCA method back to their classrooms and provide an extremely useful tool for the next generation of chemistry savvy students.


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