Digital Commons Network^™

Providing Reliable Data Transport For Dynamic Event Sensing In Wireless Sensor Networks, Yuyan Xue, Byrav Ramamurthy, Yong Wang

School of Computing: Conference and Workshop Papers

In this paper, we propose a Loss Tolerant Reliable (LTR) data transport mechanism for dynamic Event Sensing (LTRES) in WSNs. In LTRES, a reliable event sensing requirement at the transport layer is dynamically determined by the sink. A distributed source rate adaptation mechanism is designed, incorporating a loss rate based lightweight congestion control mechanism, to regulate the data traffic injected into the network so that the reliability requirement can be satisfied. An equation based fair rate control algorithm is used to improve the fairness among the LTRES flows sharing the congestion path. The performance evaluations show that LTRES can provide …

A Key Management Protocol For Wireless Sensor Networks With Multiple Base Stations, Yong Wang, Byrav Ramamurthy, Yuyan Xue

School of Computing: Conference and Workshop Papers

Most of the proposed key management protocols for wireless sensor networks (WSNs) in the literature assume that a single base station is used and that the base station is trustworthy. However, there are applications in which multiple base stations are used and the security of the base stations must be considered. This paper investigates a key management protocol in wireless sensor networks which include multiple base stations. We consider the situations in which both the base stations and the sensor nodes can be compromised. The proposed key management protocol, mKeying, includes two schemes, a key distribution scheme, mKeyDist, supporting multiple …

Predicting Accurate And Actionable Static Analysis Warnings: An Experimental Approach, Joseph Ronald Ruthruff, John Penix, J. David Morgenthaler, Sebastian Elbaum, Gregg Rothermel

School of Computing: Conference and Workshop Papers

Static analysis tools report software defects that may or may not be detected by other verification methods. Two challenges complicating the adoption of these tools are spurious false positive warnings and legitimate warnings that are not acted on. This paper reports automated support to help address these challenges using logistic regression models that predict the foregoing types of warnings from signals in the warnings and implicated code. Because examining many potential signaling factors in large software development settings can be expensive, we use a screening methodology to quickly discard factors with low predictive power and cost-effectively build predictive models. Our …

Performance Analysis Of Multi-Hop Ieee 802.11 Dcf Backhaul Networks, Puttipong Mahasukhon, Hamid Sharif, Michael Hempel, Ting Zhou, Wei Wang, Tadeusz Wysocki

Department of Electrical and Computer Engineering: Faculty Publications (to 2015)

Because of the wide deployment of 802.11 equipments in the past decade, current applications are not limited anymore to only single Access Points (AP) deployments for indoor usage, but have been extended to multi-hop networks to fulfill the need of high speed connectivity in mobile environments, where the analysis of multi-hop networks is extremely complicated. The behavior of an AP is dependent not only on its neighbors’ behavior, but also on the behavior of other hidden nodes. In this paper, we provide an accurate and verified multi-hop wireless backhaul analysis for performance of IEEE 802.11 DCF in terms of the …

Network Coding For Wdm All-Optical Multicast, Eric D. Manley, Jitender S. Deogun, Lisong Xu, Dennis R. Alexander

School of Computing: Technical Reports

Network coding has become a useful means for achieving efficient multicast, and the optical community has started to examine its application to optical networks. However, a number of challenges, including limited processing capability and coarse bandwidth granularity, need to be overcome before network coding can be effectively used in optical networks. In this paper, we address some of these problems. We consider the problem of finding efficient routes to use with coding, and we study the effectiveness of using network coding for optical-layer dedicated protection of multicast traffic. We also propose architectures for all-optical circuits capable of performing the processing …

Non-Optimal Receiver For Space Time Spreading Across A Time Hopping Over Ultra Wideband Ppm, Peter Vial, Beata Wysocki, Tadeusz Wysocki

Department of Electrical and Computer Engineering: Faculty Publications (to 2015)

A novel non-optimal chip based technique is proposed to use two antennas to transmit data across a Direct Sequence Time Hopping Ultra Wideband dual antenna wireless communication system to a single receiver. The spread data is sent over the independent channels using the Space Time Spreading technique to encode the chips which are sent on each antenna simultaneously. A hard decision is made at each chip of the spreading code received based on the known Channel State Information which Pulse Position Modulated signal was received from each antenna. The paper shows that by adapting the Space Time Spreading technique to …

Cooperative Communication In Space-Time-Frequency Coded Mb-Ofdm Uwb, L. C. Tran, A. Mertins, Tadeusz Wysocki

Department of Electrical and Computer Engineering: Faculty Publications (to 2015)

Though cooperative communication has been intensively examined for general wireless systems, such as mobile and ad-hoc networks, it has been almost unexplored in the case of Space-Time-Frequency Coded Multi-band OFDM Ultra-Wideband (STFC MB-OFDM UWB). This paper proposes a framework of cooperative communication in such systems where nodes are equipped with only one antenna. Simulation results show that cooperative communication might, in some cases, provide better error performance than non-cooperative communication without any additional transmission power.

Considering Operational Issues For Multiagent Conceptual Inferencing In A Distributed Information Retrieval Application, Leen-Kiat Soh

School of Computing: Faculty Publications

Our system, based on a multiagent framework called collaborative understanding of distributed knowledge (CUDK), is designed with the overall goal of balancing agents’ conceptual learning and task accomplishment. The tradeoff between the two is that while conceptual learning allows an agent to improve its own concept base, it could be counter-productive: conceptual learning is time consuming and requires processing resources necessary for the agent to accomplish its tasks. In our current phase of research, we investigate the roles of resource and knowledge constraints, environmental factors (such as the frequency of queries), and learning mechanisms in a CUDK-based distributed information retrieval …

I-Minds: A Multiagent System For Intelligent Computer- Supported Collaborative Learning And Classroom Management, Leen-Kiat Soh, Nobel Khandaker, Hong Jiang

School of Computing: Faculty Publications

I-MINDS provides a computer-supported collaborative learning (CSCL) infrastructure and environment for learners in synchronous learning and classroom management applications for instructors, for large classroom or distance education situations. For supporting the instructor, I-MINDS includes a teacher agent. The teacher agent allows the instructor to interact with students, manage Q&A sessions, administer quizzes, post evaluations, form groups and monitor individual and group performances. For computer-supported collaborative learning, I-MINDS, which stands for Intelligent Multiagent Infrastructure for Distributed Systems in Education, provides a student agent for each student. Each student agent monitors and models its user and carries out group formation with other …

Partial Forwarding Scheme For Dynamic Window Resizing In Live P2p Streaming Systems, Zhipeng Ouyang, Lisong Xu, Byrav Ramamurthy

School of Computing: Conference and Workshop Papers

Peer-to-peer (P2P) streaming systems, in which individual nodes or peers operated by ordinary Internet users collaborate to serve video streams, have recently aroused considerable interest in both academia and industry. An important problem in P2P streaming systems is how to reduce their consumed bandwidth, which is a major concern of Internet service providers. Our work is motivated by the fact that a user may dynamically change the size of a window displaying a video stream according to his/her personal choice, a scenario we refer to as dynamic window resizing. In this paper, we propose a scheme called the Partial Forwarding …

Computation Of A Face Attractiveness Index Based On Neoclassical Canons, Symmetry, And Golden Ratios, Kendra Schmid, David Marx, Ashok Samal

School of Computing: Faculty Publications

Analysis of attractiveness of faces has long been a topic of research. Literature has identified many different factors that can be related to attractiveness. In this research we analyze the role of symmetry, neoclassical canons, and golden ratio in the determination of attractiveness of a face. We focus on the geometry of a face and use actual faces for our analysis. We find there are some differences in the criteria used by males and females to determine attractiveness. The model we have developed to predict the attractiveness of a face using its geometry is accurate with low residual errors.

Performance Requirements And Evaluation Procedures For Advance Wide Area Detectors, Anuj Sharma, Matthew Harding, Brad Giles, Darcy M. Bullock, James R. Sturdevant, Srinivas Peeta

Department of Civil and Environmental Engineering: Faculty Publications

Dilemma zone protection ideally requires the exact position and speed of all the vehicles approaching the intersection. However, point detectors, typically used to protect vehicle incursion into the dilemma zone, only provide binary information about the presence or absence of a vehicle at a fixed point in space. The information regarding position and speed of the vehicle in subsequent time steps is extrapolated. The extrapolation error increases with the increase in projection time. Wide area detector (WAD) overcomes this drawback by tracking each vehicle at all times until they move out of range. Such a detector has the potential to …

Field Evaluation Of Alternative Real-Time Methods For Estimating Approach Delay At Signalized Intersections, Anuj Sharma, Darcy M. Bullock

Department of Civil and Environmental Engineering: Faculty Publications

Vehicle delay at a signalized intersection is among the widely used performance measures of efficiency at a signalized intersection. The Highway Capacity Manual (HCM) uses this performance measure to report the level of service at a signalized intersection. This performance measure is also used to estimate travel time along the arterials. With the advent of technological advances in the field of vehicle detection, real-time measurement of delay at a signalized intersection has become economically and computationally feasible. This paper compares three emerging techniques for estimating approach delay: an Input Output technique (IO), a Hybrid technique, and the HCM delay equation. …

Development Of Truck Weight Limits For Concrete Bridges Using Reliability Theory Desenvolvimento De Equações Para A Limitação Do Peso De Veículos De Carga Em Pontes De Concreto Através Da Teoria De Confiabilidade, L. M. Ferreira, A. S. Nowak, M. K. El Debs

Department of Civil and Environmental Engineering: Faculty Publications

The increase in gross weight limits allowed by Brazilian legislation and the soaring number of new truck configurations on national highways has called for greater attention regarding the structural safety of bridges when submitted to real traffic. This paper verifies the performance of bridges under Sao Paulo Department of Transportation jurisdiction using the reliability index β and obtains truck weight limits in order to guarantee structural integrity. The superstructures of reinforced and prestressed concrete bridges, classes 36 and 45, are considered. The ultimate limit state is verified in cross sections subjected to positive and negative critical bending moments. In case …

Chloride And The Environmental Isotopes As The Indicators Of The Groundwater Recharge In The Gobi Desert, Northwest China, J. Z. Ma, Z. Ding, John B. Gates, Y. Su

Department of Earth and Atmospheric Sciences: Faculty Publications

The long term recharge in Gobi Desert from Hexi Corridor to Inner Mongolia Plateau was estimated to Be 1 mm year^-1 by using the chloride mass balance method from one unsaturated zone profile, which shows that no effective modern recharge is taking place. A good rainfall database from Zhangye provides definition of the stable isotopic composition of modern rainfall. The signature of groundwater from the late Pleistocene differs markedly from that of the Holocene, shown clearly by the compositions of -10.5‰ δ¹⁸O as compared with values of -7‰ at the present day. It is apparent that the …

Spatial Arrangement Of Fold Types In The Zagros Simply Folded Belt, Iran, Indicated By Landform Morphology And Drainage Pattern Characteristics, Caroline M. Burberry, John W. Cosgrove, Jian Guo Liu

Department of Earth and Atmospheric Sciences: Faculty Publications

The spatial arrangement of fold types within the Zagros Simply Folded Belt was analysed using satellite images, a digital elevation model and a digital drainage network. Distinct fold geometries, principally fault-bend folds and detachment folds, can be identified by characteristic interactions with streams flowing SW from the High Zagros Mountains into the Persian Gulf. In addition, the morphology of the landforms is reflected in the minor channel patterns across the folds. This morphology can also be categorised using geomorphic indices, L/W ratio and symmetry index. The distribution of fold types is shown for the region N27°-N30°, E50°-E54° at a scale …

Evaluating The Effects Of A Trust-Building Intervention On Employee Trust, Travis O. Davidson

Theses and Dissertations

This quasiexperimental study investigated the effects a trust-building intervention had on employee trust specifically in such areas as transparency, responsiveness, understanding and caring, sincerity, and trustworthiness. Specifically, this study addressed the research questions about whether a trust-building intervention with supervisors led to improved working relationships with nonmanagement employees and whether improvements in the working relationships persisted and remained detectable for 6 weeks following the intervention.

Preintervention and postintervention questionnaires were administered to nonmanagement experimental and control groups to measure the dimensions of transparency, responsiveness, understanding and caring, sincerity, and trustworthiness. The results indicated that the trust-building intervention had a positive …

Study Of The Solar Anisotropy Of Cosmic Ray Primaries Of About 200 Gev Energy With The L3+C Muon Detector, G Baksay, L Baksay, K Dehmelt, M Hohlmann, Z Szillasi, I Vodopianov, The L3 Collaboration

Aerospace, Physics, and Space Science Faculty Publications

Context. Primary cosmic rays experience multiple deflections in the non-uniform galactic and heliospheric magnetic fields which may generate anisotropies. Aims. A study of anisotropies in the energy range between 100 and 500 GeV is performed. This energy range is not yet well explored. Methods. The L3 detector at the CERN electron-positron collider, LEP, is used for a study of the angular distribution of atmospheric muons with energies above 20 GeV. This distribution is used to investigate the isotropy of the time-dependent intensity of the primary cosmic-ray flux with a Fourier analysis. Results. A small deviation from isotropy at energies around …

Quantitative Constraints On The Transport Properties Of Hot Partonic Matter From Semi-Inclusive Single High Transverse Momentum Pion Suppression In Au+Au Collisions At √Snn = 200 Gev, Andrew Marshall Adare, Gyöngyi Baksay, László A. Baksay, Klaus Dehmelt, Marcus Hohlmann, S. Rembeczki, Phenix Collaboration

Aerospace, Physics, and Space Science Faculty Publications

The PHENIX experiment has measured the suppression of semi-inclusive single high-transverse-momentum π0's in Au+Au collisions at √sNN = 200 GeV. The present understanding of this suppression is in terms of energy loss of the parent (fragmenting) parton in a dense color-charge medium. We have performed a quantitative comparison between various parton energy-loss models and our experimental data. The statistical point-to-point uncorrelated as well as correlated systematic uncertainties are taken into account in the comparison. We detail this methodology and the resulting constraint on the model parameters, such as the initial color-charge density dNg/dy, the medium transport coefficient q, or the …

Transverse Momentum And Centrality Dependence Of Dihadron Correlations In Au+Au Collisions At Snn=200 Gev: Jet Quenching And The Response Of Partonic Matter, Andrew Marshall Adare, Gyöngyi Baksay, László Baksay, Klaus Dehmelt, Marcus Hohlmann, S. Rembeczki, Phenix Collaboration

Aerospace, Physics, and Space Science Faculty Publications

Azimuthal angle (Δ) correlations are presented for charged hadrons from dijets for 0.4

Dihadron Azimuthal Correlations In Au+Au Collisions At √Snn=200 Gev, Andrew Marshall Adare, Gyöngyi Baksay, László A. Baksay, Klaus Dehmelt, Marcus Hohlmann, S. Rembeczki, Phenix Collaboration

Aerospace, Physics, and Space Science Faculty Publications

Azimuthal angle (Δϕ) correlations are presented for a broad range of transverse momentum (0.4

Charged Hadron Multiplicity Fluctuations In Au+Au And Cu+Cu Collisions From √Snn=22.5 To 200 Gev, Andrew Marshall Adare, Gyöngyi Baksay, László A. Baksay, Klaus Dehmelt, Marcus Hohlmann, S. Rembeczki, Phenix Collaboration

Aerospace, Physics, and Space Science Faculty Publications

A comprehensive survey of event-by-event fluctuations of charged hadron multiplicity in relativistic heavy ions is presented. The survey covers Au+Au collisions at √sNN=62.4 and 200 GeV, and Cu+Cu collisions at √sNN=22.5,62.4, and 200 GeV. Fluctuations are measured as a function of collision centrality, transverse momentum range, and charge sign. After correcting for nondynamical fluctuations due to fluctuations in the collision geometry within a centrality bin, the remaining dynamical fluctuations expressed as the variance normalized by the mean tend to decrease with increasing centrality. The dynamical fluctuations are consistent with or below the expectation from a superposition of participant nucleon-nucleon collisions …

Co-Location Of Lightning Leader X-Ray And Electric Field Change Sources, John J. Howard, Martin A. Uman, Joseph R. Dwyer, Dustin Hill, Christopher J. Biagi, Ziad H. Saleh, Jason E. Jerauld, Hamid K. Rassoul

Aerospace, Physics, and Space Science Faculty Publications

Using an eight-station time of arrival (TOA) network composed of NaI(Tl) scintillation detectors and wideband electric field derivative (dE/dt) antennas covering approximately 1 km² on the ground, we have located both the sources of X-ray emissions and electric field changes produced during the leader phase of both downward negative natural and rocket-triggered lightning strokes. We show that the sources of X rays and leader step electric field changes are co-located in space within 50 m and that the located X rays are emitted 0.1 to 1.3 μs after the origin of the leader step electric field changes.

Hubble Space Telescope Near-Infrared Snapshot Survey Of 3cr Radio Source Counterparts. Ii. An Atlas And Inventory Of The Host Galaxies, Mergers, And Companions, David J. E. Floyd, Eric Perlman

Aerospace, Physics, and Space Science Faculty Publications

We present the second part of an H-band (1.6 μm) "atlas" of z < 0.3 3CR radio galaxies, using the Hubble Space Telescope Near Infrared Camera and Multi-Object Spectrometer (HST NICMOS2). We present new imaging for 21 recently acquired sources and host galaxy modeling for the full sample of 101 (including 11 archival) - an 87% completion rate. Two different modeling techniques are applied, following those adopted by the galaxy morphology and the quasar host galaxy communities. Results are compared and found to be in excellent agreement, although the former breaks down in the case of sources with strong active galactic nuclei (AGNs). Companion sources are tabulated, and the presence of mergers, tidal features, dust disks, and jets are cataloged. The tables form a catalog for those interested in the structural and morphological dust-free host galaxy properties of the 3CR sample, and for comparison with morphological studies of quiescent galaxies and quasar host galaxies. Host galaxy masses are estimated and found to typically lie at around 2 × 1011 M⊙. In general, the population is found to be consistent with the local population of quiescent elliptical galaxies, but with a longer tail to low Sérsic index, mainly consisting of low-redshift (z < 0.1) and low-radio-power (FR I) sources. A few unusually disky FR II host galaxies are picked out for further discussion. Nearby external sources are identified in the majority of our images, many of which we argue are likely to be companion galaxies or merger remnants. The reduced NICMOS data are now publicly available from our Web site.

Restructuring A Secondary Business Curriculum For The 21st Century, Eric Springer

Graduate Research Papers

This paper reviews what secondary business educators can do to restructure a business curriculum for the 21 st century and how they can do it effectively. It was written to describe today's workplace, the skills that employers are expecting workers to have, the current trends and reform evolving in high school business education, and the projects, strategies, and tools that can be used by business teachers to prepare students for success in the workplace. The literature review discusses the state of Iowa's 21 st century skills curriculum that was established in recent years. The skills curriculum includes employability skills, financial …

Comparison Of Different Chemical Pulps From Wheat Straw And Bleaching With Xylanase Pre-Treated Ecf Method, Sai̇m Ateş, Celi̇l Atik, Yonghao Ni, Esat Gümüşkaya

Turkish Journal of Agriculture and Forestry

Different pulping processes, kraft-anthraquinone (AQ), bio-kraft, soda-AQ, ALCELL, and FORMACELL were studied for wheat straw. Fungal pre-treatment with Ceriporiopsis subvermispora, white rot fungi, was applied to wheat straw before kraft-AQ pulping, the so-called bio-kraft process. Fiber properties, carbohydrate contents, FT-IR analyses, strength properties of resultant paper, and bleachability characteristics were included to determine the properties of these pulp samples. In addition, the effects of the xylanase pre-treatment on the subsequent Elemental Chlorine Free (ECF) bleaching process were investigated. The results indicated that kraft-AQ pulps from wheat straw exhibited better characteristics than the other pulp samples with lower kappa number, higher …

Mechanisms Of Hemoglobin Adaptation To High Altitude Hypoxia, Jay F. Storz, Hideaki Moriyama

Hideaki Moriyama Publications

Evidence from a number of vertebrate taxa suggests that modifications of hemoglobin (Hb) function may often play a key role in mediating an adaptive response to high altitude hypoxia. The respiratory functions of Hb are a product of the protein’s intrinsic O₂-binding affinity and its interactions with allosteric effectors such as protons, chloride ions, CO₂, and organic phosphates. Here we review several case studies involving high altitude vertebrates where it has been possible to identify specific mechanisms of Hb adaptation to hypoxia. In addition to comparative studies of Hbs from diverse animal species, functional studies of …

Mechanisms Of Hemoglobin Adaptation To High Altitude Hypoxia, Jay F. Storz, Hideaki Moriyama

Hideaki Moriyama Publications

Evidence from a number of vertebrate taxa suggests that modifications of hemoglobin (Hb) function may often play a key role in mediating an adaptive response to high altitude hypoxia. The respiratory functions of Hb are a product of the protein’s intrinsic O₂-binding affinity and its interactions with allosteric effectors such as protons, chloride ions, CO₂, and organic phosphates. Here we review several case studies involving high altitude vertebrates where it has been possible to identify specific mechanisms of Hb adaptation to hypoxia. In addition to comparative studies of Hbs from diverse animal species, functional studies of …

Insulating To Reduce Heating Costs, Kenneth Hellevang, Carl Pedersen

AE Series – Agricultural Engineering/ABEN

No abstract provided.

Farmstead Energy Audit, John Nowatzki, Tom Scherer, Kenneth Hellevang, Carl Pedersen

AE Series – Agricultural Engineering/ABEN

No abstract provided.