Engineering Commons^™

Time-Domain Electric-Field Integral Equation With Central Finite Difference, Baek Ho Jung, Tapan Kumar Sarkar

Electrical Engineering and Computer Science - All Scholarship

In this paper, we present a new formulation using the time-domain electric-field integral equation (TD-EFIE) to obtain a transient scattering response from arbitrarily shaped conducting bodies. The time derivative of the magnetic vector potential is approximated with a central finite difference, and the scalar potential is time averaged by dividing it into two terms. This approach with an implicit method using central-difference results in accurate and stable transient scattering responses from conducting objects. Detailed mathematical steps are included, and several numerical results are presented.

Entropy Generation Method To Quantify Thermal Comfort, S. C. Boregowda, S. N. Tiwari, S. K. Chaturvedi

Mechanical & Aerospace Engineering Faculty Publications

The present paper presents a thermodynamic approach to assess the quality of human-thermal environment interaction and quantify thermal comfort. The approach involves development of entropy generation term by applying second law of thermodynamics to the combined human-environment system. The entropy generation term combines both human thermal physiological responses and thermal environmental variables to provide an objective measure of thermal comfort. The original concepts and definitions form the basis for establishing the mathematical relationship between thermal comfort and entropy generation term. As a result of logic and deterministic approach, an Objective Thermal Comfort Index (OTCI) is defined and established as a …

Nebraska Summary 354: Agco Dt200 Diesel, Nebraska Tractor Test Lab

Nebraska Tractor Tests

No abstract provided.

Test 1791: John Deere 9400t Also 9420t 24 Speed, Nebraska Tractor Test Lab

Nebraska Tractor Tests

No abstract provided.

Test 1790: 9300 T 24 Speed, Nebraska Tractor Test Lab

Nebraska Tractor Tests

No abstract provided.

Test 1797: Case Ih Stx 325/New Holland Tj 325 Diesel, Nebraska Tractor Test Lab

Nebraska Tractor Tests

No abstract provided.

Test 1796: Case Ih Stx 275/New Holland Tj 275 Diesel, Nebraska Tractor Test Lab

Nebraska Tractor Tests

No abstract provided.

Test 1797: Case Ih Stx 325/New Holland Tj 325 Diesel, Nebraska Tractor Test Lab

Nebraska Tractor Tests

No abstract provided.

Test 1794: White 8710 Also Agco Allis 9775 (Cummins Engine) Also Agco Dt200, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …

Tractor Test 1780a: White 8785, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …

Tractor Test 1795: White 8810, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …

Test 1792: Massey Ferguson 2210 Diesel 15-Speed, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA

The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data.

EXPLANATION OF THE TEST PROCEDURES

Purpose

The purpose of …

Test 1793: Massey Ferguson 2220 Diesel 12-Speed, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA

The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data.

EXPLANATION OF THE TEST PROCEDURES

Purpose

The purpose of …

Nebraska Summary 388: Fendt 918 Vario Diesel, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA

The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data.

EXPLANATION OF THE TEST PROCEDURES

Purpose

The purpose of …

Nebraska Summary 389: Fendt 920 Vario Diesel, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA

The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data.

EXPLANATION OF THE TEST PROCEDURES

Purpose

The purpose of …

Nebraska Summary 390: Fendt 924 Vario Diesel, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA

The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data.

EXPLANATION OF THE TEST PROCEDURES

Purpose

The purpose of …

Nebraska Summary 391: Fendt 926 Vario Diesel, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA

The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data.

EXPLANATION OF THE TEST PROCEDURES

Purpose

The purpose of …

Future Research Vessels, Larry P. Atkinson

CCPO Publications

The academic research vessel fleet in the United States is embarking on a great experiment. By 2004 we will know if SWATH vessels such as the Mlo Moana and the possible built Woods Hole Oceanographic Institution coastal SWATH have such great advantages that all future vessels will be of SWATH design. Or, we will find that the two hull forms have distinct niches and the fleet will evolve with a strategic mix. Regardless of the Mure hull form research vessels will grow in size to accommodate advanced technology and the people to run and maintain it. The research vessel will …

Obiwan - An Internet Protocol Router In Reconfigurable Hardware, Florian Braun, Marcel Waldvogel, John Lockwood

All Computer Science and Engineering Research

The ongoing exponential increase of line speed in the Internet and combined with the uncountable requests for increased functionality of network devices presents a major challenge. These demands call for the use of reprogrammable hardware to provide the required flexible high-speed functionaltiy. The Field Programmable Port Extender (FPX) provides such an environment for development of networking components in reprogrammable hardware. We present the high-speed IP routing components in reprogrammable hardware. We present the high-speed IP routing module "OBIWAN" (Optimal Binary search IP lookup for Wide Area Networks) built on top of an IP processing framework.

Generalized Rad Module Interface Specification Of The Field-Programmable Port Extender (Fpx) Version 2.0, David E. Taylor, John W. Lockwood, Sarang Dharmapurikar

All Computer Science and Engineering Research

The Field-programmable Port eXtender (FPX) provides dynamic, fast, and flexible mechanisms to process data streams at the ports of the Washington University Gigabit Switch (WUGS-20). By performing all computations in FPGA hardware, cells and packets can be processed at the full line speed of the transmission interface, currently 2.4 Gbits/sec. In order to design and implement portable hardware modules for the Reprogrammable Application Devide (RAD) on the FPX board, all modules should conform to a standard interface. This standard interface specifies how modules receive and transmit ATM cells of data flows, prevent data loss during reconfiguration, and access off-chip memory. …

Design Of Wavelength Converting Switches For Optical Burst Switching, Jeyashankher Ramamirtham, Jonathan Turner

All Computer Science and Engineering Research

Optical Burst Switching (OBS) is an experimental network technology that enables the construction of very high capacity routers, using optical data paths and electronic control. In this paper, we study two designs for wavelength converting switches that are suitable for use in optical burst switching systems and evaluate their performance. Both designs use tunable lasers to implement wavelength conversion. One is strictly nonblocking design, that also requires optical crossbars. The second substitutes Wavelength Grating Routers (WGR) for the optical crossbars, reducing cost, but introducing some potential for blocking. We show how the routing problem for the WGR-based switches can be …

The Fpx Kcpsm Module: An Embedded, Reconfigurable Active Processing Module For The Field Programmable Port Extender (Fpx), Henry Fu, John W. Lockwood

All Computer Science and Engineering Research

While hardware plugins are well suited for processing data with high throughput, software plugins are well suited for implementing complex control functions. A plugin module has been implemented for the FPX that executes software on an embedded soft-core processor. By including this module in an FPX design, it is possible to implement active networking functions on the FPX using both hardware and software. The KCPSM, an 8-bit microcontroller developed by Xilinx Corp., has been embedded into an FPX module. The module includes circuits to be reprogrammed over the network and to execute new programs between the processing of data packerts. …

Performance Of Deferred Reservations In Data Networks, Samphel Norden, Jonathan Turner

All Computer Science and Engineering Research

This paper studies the performance of deferred resource reservation in data networks. Conventional resource reservation protocols, such as PNNI and RSVP adopt an all-or-nothing approach, where partially acquired resources must be released if resources are not available at all links on the chosen path. During periods of high network load, this leads users to retry requests repeatedly, adding control traffic at exactly the time when the network's capacity to process that control traffic is exhausted. Deferred REServation (DRES) can significantly improve performance by reducing the overall call rejection probability, allowing more traffic to be carried, using the same resources. Call …

A Termination Detection Protocol For Use In Mobile Ad Hoc Networks, Gruia-Catalin Roman, Jamie Payton

All Computer Science and Engineering Research

As computing devices become smaller and wireless networking technologies improve, the popularity of mobile computing continues to rise. In today's business world, many consider devices such as cell phones, PDAs, and laptops as essential tools. As these and other devices become increasingly independent of the wired infrastructure, new kinds of applications that assume an ad hoc network infrastructure will need to be deployed. Such a setting poses new challenges for the software developer, e.g., the lack of an established network topology, bandwidth limitations, and frequent disconnections. In this paper, we begin to explore design strategies for developing applications over ad …

Efficient Queue Management For Tcp Flows, Anshul Kantawala, Jonathan Turner

All Computer Science and Engineering Research

Packets in the Internet can experience large queueing delays during busy periods. Backbone routers are generally engineered to have large buffers, in which packets may wait as long as half a second (assuming FIFO service, longer otherwise). During congestion periods, these bufferfs may stay close to full, subjecting packets to long delays, even when the intrinsic latency of the path is relatively small. This paper studies the performance improvements that can be obtained by using more sophisticated packet schedulers, than are typical of Internet routers. The results show that the large buffers found in WAN routers ocntribute only marginally to …

Scheduling Processing Resources In Programmable Routers, Prashanth Pappu, Tilman Wolf

All Computer Science and Engineering Research

To provide flexibility in deploying new protocols and services, general-purpose processing engines are being placed in the datapath of routers. Such network processors are typically simple RISC multiprocessors that perform forwarding and custom application processing of packets. The inherent unpredictability of execution time of arbitrary instruction code poses a significant challenge in providing QoS guarantees for data flows that compete for such processing resources in the network. However, we show that network processing workloads are highly regular and predictable. Using estimates of execution times of various applications on packets of given lengths, we provide a method for admission control and …

An Efficient Quality Scalable Motion-Jpeg2000 Transmission Scheme, Ruibiao Qiu, Wei Yu

All Computer Science and Engineering Research

Video application over the Internet are getting increasingly popular because of the explosive growth of the Internet. However, video packets loss due to network congestions can degrade the video quality substantially. In this paper, we propose a transmission scheme for Motion-JPEG2000. It can be implemented in an active network environment efficiently. Our simulation shows that our scheme gracefully adapts to network congestion and improves the quality of video transmission in congested IP networks.

Services Provision In Ad Hoc Networks, Radu Handorean, Gruia-Catalin Roman

All Computer Science and Engineering Research

The client-server model continues to dominate distributed computing with increasingly more flexible variants being deployed. Many are centered on the notion of discovering services at run time and on allowing any system component to act as a service provider. The result is a growing reliance on the service registration and discovery mechanisms. This paper addresses the issue of facilitating such service provision capabilities in the presence of (logical and physical) mobility exhibited by applications executing over ad hoc networks. The solution being discussed entailes a new kind of service model, which we were able to build as an adaption layer …

Implementation Of An Open Multi-Service Router, Fred Kuhns, John Dehart, Ralph Keller, John Lockwood, Prashanth Papu, Jyoti Parwatikar, Ed Spitznagel, David Richard, David Taylor, Jon Turner, Ken Wong

All Computer Science and Engineering Research

This paper describes the design, implementation, and performance of an open, high-performance, dynamically reconfigurable Multi-Service Router (MSR) being developed at Washington University in St. Louis. This router provides an experimentation platform for research on protocols, router software, and hardware design, network management, quality of service and advanced applications. The MSR has been designed to be flexible, without sacrificing performance. It support gigabit links and uses a scalable architecture suitable for supporting hundreds or even thousands of links. The MSR's flexibility makes it an ideal platform for experimental research on dynamically extensible networks that implement higher level functions in direct support …

Dynamics Of Poly(Vinyl Acetate)-D₃ On Silica, Robert D. O'Connor, Frank D. Blum, Gu Xu

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Poly(vinyl acetate) (PVAc) is an important polymer in applications because of both its bulk and surface characteristics. Its chain architecture gives it a low Tg and, generally, good qualities for processing and applications, which include paints, adhesives, thin films and surface coatings. In this study, we investigate the surface dynamics of PVAc absorbed onto silica with deuterium nuclear magnetic resonance (2H NMR). For dynamics studies, 2H NMR is an excellent technique because it uses an innocuous probe that can report on correlation times (τc) from approximately 10-8 s to 10 s. We report the use of two-dimensional exchange NMR (2D-X) …