Modeling Solvent Drying of Coated Webs Including the Initial Transient

A complete model for the drying of coated webs. as implemented in the spreadsheet DRYWEB for Lotus and for Excel, is described. The model predicts the temperatures and solvent levels throughout the length of the dryer. The initial transient as the coated web approaches the equilibrium temperature in the consiant rate period is calculated. The coating is divided into slices for a finite difference calculation of solvent diffusion to the surface, using a simple free volume model of diffusion. The semi-empirical constants needed can be found from one or two trial runs. The possible use of infra-red heating in addition to convection heating is included in both the constant and falling rates. The calculation of infra-red energy is discussed. The model assumes that the temperature is uniform from the top of the coating to the bottom of the base, and that assumption is justified.     

Identification of the combustion behaviour of lignite char between 350 and 900 °C

The combustion behaviour of four different lignite samples pyrolysed at 800 and 1000 °C has been studied. The reaction order and the activation energy of the char combustion reaction can be easily determined from the time to reach 50% conversion. Under 550 °C the reaction order of lignite samples are 0.7 and the activation energies are 27.4–27.9 kcal gmole^?1. Above 550 °C the measurement of the intrinsic reaction rate is limited by the film diffusion resistance. The pyrolysis temperature affects the reactivity significantly. The reactivity of char pyrolysed at 800 °C is 3.5 times that of char pyrolysed at 1000 °C.     

Decentralized adaptive recurrent neural control structure

This paper presents a novel decentralized variable structure neural control approach for large-scale uncertain systems, which is developed using recurrent high-order neural networks (RHONN). It is assumed that each subsystem belongs to a class of block-controllable nonlinear systems whose vector fields includes interconnection terms, which are bounded by nonlinear functions. A decentralized RHONN structure and the respective learning law are proposed in order to approximate online the dynamical behavior of each nonlinear subsystem. The control law, which is able to regulate and to track the desired reference signals, is designed using the well-known variable structure theory. The stability of the whole system is analyzed via the Lyapunov methodology. The applicability of the proposed decentralized identification and control algorithm is illustrated via simulations as applied to an interconnected double inverted pendulum.     

Personal Trusted Devices for Web Services: Revisiting Multilevel Security

In this paper we revisit the concept of mandatory access control and investigate its potential with personal digital assistants (PDA). Only if applications are clearly separated and Trojans cannot leak personal information can these PDAs become personal trusted devices. Limited processing power and memory can be overcome by using Web services instead of full-fledged applications – a trend also in non-mobile computing. Web services, however, introduce additional security risks, some of them specific for mobile users. We propose an identification scheme that can be effectively used to protect privacy and show how this system builds upon a light-weight version of mandatory access control.     

Smoothing Streams in an In-Home Digital Network: Optimization of Bus and Buffer Usage

In an in-home digital network it may be expected that several data streams (audio, video) run simultaneously over a shared communication device, e.g., a bus. The burstiness of a data stream can be reduced by buffering data at the sending and receiving side, thereby allowing a lower bus share allocation for the stream. In this paper we present an algorithm that determines how much of the bus capacity and buffer space should be allocated to each stream, in order to have a feasible transmission schedule for each stream. Furthermore, the algorithm determines a transmission schedule for each stream, indicating how much data is transmitted over time. We show how this multiple-stream problem can be solved by repeatedly solving single-stream problems. We present efficient algorithms to solve these single-stream problems. Furthermore, we present some experimental results. This revised version was published online in September 2006 with corrections to the Cover Date.     

Electrochemically Tuned Properties for Electrolyte‐Free Carbon Nanotube Sheets

Injecting high electronic charge densities can profoundly change the optical, electrical, and magnetic properties of materials. Such charge injection in bulk materials has traditionally involved either dopant intercalation or the maintained use of a contacting electrolyte. Tunable electrochemical charge injection and charge retention, in which neither volumetric intercalation of ions nor maintained electrolyte contact is needed, are demonstrated for carbon nanotube sheets in the absence of an applied field. The tunability of electrical conductivity and electron field emission in the subsequent material is presented. Application of this material to supercapacitors may extend their charge‐storage times because they can retain charge after the removal of the electrolyte.     

An On-Chip Spectrum Analyzer for Analog Built-In Testing

This paper presents an analog built-in testing (BIT) architecture and its implementation. It enables the frequency response and harmonic distortion characterizations of an integrated device-under-test (DUT) through a digital off-chip interface. External analog instrumentation is avoided, reducing test time and cost. The proposed on-chip testing scheme uses a digital frequency synthesizer and a simple signal generator synchronized with a switched capacitor bandpass filter. A general methodology for the use of this structure in the functional verification of a DUT is also provided. The circuit-level design and experimental results of an integrated prototype in standard CMOS 0.5 m technology are presented to demonstrate the feasibility of the proposed BIT technique.Marcia G. Mendez-Rivera was born in Irapuato, Mexico in 1972. She received the Communications and Electronics Engineering Degree from the Universidad de Guanajuato, Guanajuato, Mexico. in 1996, the M.Sc. degree from the Instituto Nacional de Astrofisica, Optica y Electronica (INAOE), Puebla, Mexico in 1998 and the M.Sc. from Texas A&M University, College Station in 2002. Her research interest is in the design and fabrication of analog and mixed-signal circuits.Alberto Valdes-Garcia born in 1978, grew up in San Mateo Atenco, Mexico. He received the B.S. in Electronic Systems Engineering degree from the Monterrey Institute of Technology (ITESM), Campus Toluca, Mexico in 1999 (with honors as the best score from all majors). Since the fall of 2000 he has been working towards the Ph.D. degree at Analog and Mixed-Signal Center (AMSC), Texas A&M University. During the spring and summer of 2000 he was a Design Engineer with Motorola Broadband Communications Sector. In the summer of 2002 he was with the Read Channel Design Group at Agere Systems where he investigated wide tuning range GHz LC VCOs for mass storage applications. During the summer of 2004 he was with the Mixed-Signal Communications IC Design Group at the IBM T. J. Watson Research Center, where worked on design and analysis of SiGe power amplifiers for millimeter wave radios. Since the fall of 2001 he has been a Semiconductor Research Corporation (SRC) research assistant at the AMSC working on the development of analog built-in testing techniques. Since the fall of 2000, Alberto has been the recipient of a scholarship from the Mexican National Council for Science and Technology (CONACYT). He represented Mexico in the 1994 Odyssey of the Mind World Creativity Contest and in the 1997 International Exposition for Young Scientists. His present research interests include built-in testing implementations for analog and RF circuits, system level design for wireless receivers and RF circuit design for UltraWideBand (UWB) communications.Jose Silva-Martinez was born in Tecamachalco, Puebla, México. He received the B.S. degree in electronics from the Universidad Autónoma de Puebla, México, in 1979, the M.Sc. degree from the Instituto Nacional de Astrofísica Optica y Electrónica (INAOE), Puebla, México, in 1981, and the Ph.D. degree from the Katholieke Univesiteit Leuven, Leuven Belgium in 1992. From 1981 to 1983, he was with the Electrical Engineering Department, INAOE, where he was involved with switched-capacitor circuit design. In 1983, he joined the Department of Electrical Engineering, Universidad Autonoma de Puebla, where he remained until 1993; He was a co-founder of the graduate program on Opto-Electronics in 1992. From 1985 to 1986, he was a Visiting Scholar in the Electrical Engineering Department, Texas A&M University. In 1993, he re-joined the Electronics Department, INAOE, and from May 1995 to December 1998, was the Head of the Electronics Department; He was a co-founder of the Ph.D. program on Electronics in 1993. He is currently with the Department of Electrical Engineering (Analog and Mixed Signal Center) Texas A&M University, at College Station, where He holds the position of Associate Professor. His current field of research is in the design and fabrication of integrated circuits for communication and biomedical application. Dr. Silva-Martinez has served as IEEE CASS Vice President Region-9 (1997–1998), and as Associate Editor for IEEE Transactions on Circuits and Systems part-II from 1997–1998 and May 2002–December 2003. Since January 2004 is serving as Associate Editor of IEEE TCAS Part-I. He was the main organizer of the 1998 and 1999 International IEEE-CAS Tour in region 9, and Chairman of the International Workshop on Mixed-Mode IC Design and Applications (1997–1999). He is the inaugural holder of the TI Professorship-I in Analog Engineering, Texas A&M University. He was a co-recipient of the 1990 European Solid-State Circuits Conference Best Paper Award.Edgar Sánchez-Sinencio was born in Mexico City, Mexico. He received the degree in communications and electronic engineering (Professional degree) from the National Polytechnic Institute of Mexico, Mexico City, the M.S.E.E. degree from Stanford University, CA, and the Ph.D. degree from the University of Illinois at Urbana-Champaign, in 1966, 1970, and 1973, respectively. In 1974 he held an industrial Post-Doctoral position with the Central Research Laboratories, Nippon Electric Company, Ltd., Kawasaki, Japan. From 1976 to 1983 he was the Head of the Department of Electronics at the Instituto Nacional de Astrofísica, Optica y Electrónica (INAOE), Puebla, Mexico. He was a Visiting Professor in the Department of Electrical Engineering at Texas A&M University, College Station, during the academic years of 1979–1980 and 1983-1984. He is currently the TI J Kilby Chair Professor and Director of the Analog and Mixed-Signal Center at Texas A&M University. He was the General Chairman of the 1983 26th Midwest Symposium on Circuits and Systems. He was an Associate Editor for IEEE Trans. on Circuits and Systems, (1985–1987), and an Associate Editor for the IEEE Trans. on Neural Networks. He is the former Editor-in-Chief of the Transactions on Circuits and Systems II. He is co-author of the book Switched Capacitor Circuits (Van Nostrand-Reinhold 1984), and co-editor of the book Low Voltage/Low-Power Integrated Circuits and Systems (IEEE Press 1999). In November 1995 he was awarded an Honoris Causa Doctorate by the National Institute for Astrophysics, Optics and Electronics, Mexico. The first honorary degree awarded for Microelectronic Circuit Design contributions. He is co-recipient of the 1995 Guillemin-Cauer for his work on Cellular Networks. He is a former IEEE CAS Vice President-Publications. He was also the co-recipient of the 1997 Darlington Award for his work on high-frequency filters He received the Circuits and Systems Society Golden Jubilee Medal in 1999. He was the IEEE Circuits and Systems Society, Representative to the Solid-State Circuits Society (2000–2002). He is presently a member of the IEEE Solid-State Circuits Fellow Award Committee. His present interests are in the area of RF-Communication circuits and analog and mixed-mode circuit design. He is an IEEE Fellow Member since 1992.