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Full-Text Articles in Physical Sciences and Mathematics

On The Potential Uses Of Static Offsets Derived From Low-Cost Community Instruments And Crowd-Sourcing For Earthquake Monitoring And Rapid Response, Sarah Minson, Benjamin Brooks, Jessica Murray, Robert Iannucci Dec 2012

On The Potential Uses Of Static Offsets Derived From Low-Cost Community Instruments And Crowd-Sourcing For Earthquake Monitoring And Rapid Response, Sarah Minson, Benjamin Brooks, Jessica Murray, Robert Iannucci

Robert A Iannucci

No abstract provided.


Adaptive Circuits Using Pfet Floating-Gate Devices, Paul Hasler, Bradley Minch, Chris Diorio Jul 2012

Adaptive Circuits Using Pfet Floating-Gate Devices, Paul Hasler, Bradley Minch, Chris Diorio

Bradley Minch

In this paper, we describe our floating-gate pFET device, with its many circuit applications and supporting experimental measurements. We developed these devices in standard double-poly CMOS technologies by utilizing many effects inherent in these processes. We add floating-gate charge by electron tunneling, and we remove floating-gate charge by hot-electron injection. With this floating-gate technology, we cannot only build analog EEPROMs, we can also implement adaptation and learning when we consider floating-gate devices to be circuit elements with important time-domain dynamics. We start by discussing non-adaptive properties of floating-gate devices and we present two representative non-adaptive applications. First, we discuss using …


Optimal Synthesis Of Mite Translinear Loops, Shyam Subramanian, David Anderson, Paul Hasler, Bradley Minch Jul 2012

Optimal Synthesis Of Mite Translinear Loops, Shyam Subramanian, David Anderson, Paul Hasler, Bradley Minch

Bradley Minch

A procedure for synthesizing multiple-input translinear element (MITE) networks that implement a given system of translinear-loop equations (STLE) is presented. The minimum number of MITEs required for implementing the STLE, which is equal to the number of current variables in the STLE, is attained. The number of input gates ofthe MITEs is minimal amongst those MITE networks that satisfy the STLE and have the minimum number of MITEs. The synthesized MITE networks have a unique operating point and, in many cases, the network is guaranteed to be stable in a particular sense. This synthesis procedure exploits the relationship between MITEproduct-of-power-law …


Synthesis Of Dynamic Multiple-Input Translinear Element Networks, Bradley Minch Jul 2012

Synthesis Of Dynamic Multiple-Input Translinear Element Networks, Bradley Minch

Bradley Minch

In this paper, the author discusses an approach to the synthesis of dynamic translinear circuits built from multiple-input translation elements (MITEs). In this method, we realize separately the basic static nonlinearities and dynamic signal-processing functions that when cascaded together, form the system that one wishes to construct. The circuit is then simplified systematically through local transformations that do not alter the behavior of the system. The author illustrates the method by synthesizing a simple nonlinear dynamical system, an RMS-DC converter.


Analog Vlsi Implementation Of Support Vector Machine Learning And Classification, Sheng-Yu Peng, Bradley Minch, Paul Hasler Jul 2012

Analog Vlsi Implementation Of Support Vector Machine Learning And Classification, Sheng-Yu Peng, Bradley Minch, Paul Hasler

Bradley Minch

We propose an analog VLSI approach to implementing the projection neural networks adapted for the supportvector machine with radial-basis kernel functions, which are realized by a proposed floating-gate bump circuit with the adjustable width. Other proposed circuits include simple current mirrors and log-domain Alters. Neither resistors nor amplifiers are employed. Therefore it is suitable for large-scale neural network implementations. We show the measurement results of the bump circuit and verify the resulting analog signal processing system on the transistor level by using a SPICE simulator. The same approach can also be applied to the support vectorregression. With these analog signal …


A Long-Channel Model For The Asymmetric Double-Gate Mosfet Valid In All Regions Of Operation, Abhishek Kammula, Bradley Minch Jul 2012

A Long-Channel Model For The Asymmetric Double-Gate Mosfet Valid In All Regions Of Operation, Abhishek Kammula, Bradley Minch

Bradley Minch

We present a physically based, continuous analytical model for long-channel double-gate MOSFETs. The model is particularly well suited for implementation in circuit simulators due to the simple expressions for the current andthe continuous nature of the derivatives of the current which improves convergence behavior.


Designing A Small-Footprint Curriculum In Computer Science, Allen Downey, Lynn Stein Jul 2012

Designing A Small-Footprint Curriculum In Computer Science, Allen Downey, Lynn Stein

Lynn Andrea Stein

We describe an innovative computing curriculum that combines elements of computer science, engineering and design. Although it is tailored to the constraints we face at Olin College, it contains elements that are applicable to the design of a CS major at a small school, a CS minor, or an interdisciplinary program that includes computing. We present the core courses in the program as well as several courses that are meant to connect the computing curriculum to other fields. We summarize the lessons we have learned from the first few years of this program.


Lachesis: A Job Scheduler For The Cray T3e, Allen B. Downey Jul 2012

Lachesis: A Job Scheduler For The Cray T3e, Allen B. Downey

Allen B. Downey

This paper presents the design and implementation of Lachesis, a job scheduler for the Cray T3E. Lachesis was developed at the San Diego Supercomputer Center (SDSC) in an attempt to correct some problems with the scheduling system Cray provides with the T3E.


On The Issue Of Decoupled Decoding Of Codes Derived From Quaternion Orthogonal Designs, Tadeusz Wysocki, Beata Wysocki, Sarah Spence Adams Jul 2012

On The Issue Of Decoupled Decoding Of Codes Derived From Quaternion Orthogonal Designs, Tadeusz Wysocki, Beata Wysocki, Sarah Spence Adams

Sarah Spence Adams

Quaternion orthogonal designs (QODs) have been previously introduced as a basis for orthogonal space-time polarization block codes (OSTPBCs). This note will serve to correct statements concerning the optimality of a decoupled maximum-likelihood (ML) decoding algorithm. It will be shown that when compared to coupled decoding, the decoupled decoding is only optimal in certain cases. This raises several open problems concerning the decoding of OSTPBCs.


Technology Enhanced Learning: Students' Views, Eileen O'Donnell, Mary Sharp Dec 2011

Technology Enhanced Learning: Students' Views, Eileen O'Donnell, Mary Sharp

Eileen O'Donnell

User feedback is very important in all areas of computer science especially in the development of computer applications. Hence, student feedback on the use of technology enhanced learning in higher education in Ireland is relevant to the quality of the learning resources to be created by learning designers and academics in the future. The book “Student Reactions to Learning with Technologies: Perceptions and Outcomes” (Moyle & Wijngaards, 2012) was published by IGI Global in October 2011. This book includes contributions from various authors who are interested in students’ feedback regarding how technology has impacted on their educational experience. This book …


The Human Computer Interaction Issues Associated With The Creation Of Personalized Role Playing Simulations, Eileen O'Donnell, Catherine Mulwa, Mary Sharp, Vincent Wade Sep 2011

The Human Computer Interaction Issues Associated With The Creation Of Personalized Role Playing Simulations, Eileen O'Donnell, Catherine Mulwa, Mary Sharp, Vincent Wade

Eileen O'Donnell

The human computer interaction issues associated with the creation of personalized role playing simulations are discussed in this paper. This paper is aimed at those who are interested in building authoring applications which enable educators to build role playing simulated e-learning resources to use with their students. One of the main issues which have come to our attention is that many learning designers and educators do not understand what exactly it is we are trying to achieve by creating personalized role playing simulations. Also, how to gauge the pedagogic merits which can be achieved by using these e-learning resources. Potential …


Building An Interdisciplinary Research Program In Water Conservation: Approach, Preliminary Findings, And Next Steps, David E. Rosenberg, Joanna Endter-Wada, Arthur Caplan, Diana T. Glenn Apr 2011

Building An Interdisciplinary Research Program In Water Conservation: Approach, Preliminary Findings, And Next Steps, David E. Rosenberg, Joanna Endter-Wada, Arthur Caplan, Diana T. Glenn

Diana T. Glenn

Effective urban water conservation programs must harness a synergy of new technologies, public policies, social cost pricing, information dissemination, citizen engagement, and coordinated actions across decision making scales. Together, these factors affect the volume of water an individual user ultimately saves and the overall success of a conservation program or programs. Over the past 18 months, we have started building an interdisciplinary research program in urban water conservation to quantify and assess the effects of these interconnected factors to motivate citizen engagement. We have interviewed water utility managers and conservation coordinators across the state of Utah, held focus groups with …


On The Road To Intelligent Web Applications, Hisham Assal, Kym J. Pohl, Jens G. Pohl Jun 2010

On The Road To Intelligent Web Applications, Hisham Assal, Kym J. Pohl, Jens G. Pohl

Jens G. Pohl

Increasing access to data sources on the Internet offers expanding opportunities for equipping intelligent applications with the content they require whether broad in scope or rich in detail. Although typically originating within the web in a semi-structured form, with the use of inference-based translation and analysis mechanisms such content can be transformed into useful information and ultimately into actionable knowledge. Service-Oriented Architecture (SOA) offers a platform for accessing the web as invocable resources and effectively incorporating multiple sources of data and capabilities on the Internet into enterprise applications. Adding inference capabilities to SOA-based applications not only aids in the translation …


On The Issue Of Decoupled Decoding Of Codes Derived From Quaternion Orthogonal Designs, Tadeusz Wysocki, Beata Wysocki, Sarah Spence Adams Aug 2009

On The Issue Of Decoupled Decoding Of Codes Derived From Quaternion Orthogonal Designs, Tadeusz Wysocki, Beata Wysocki, Sarah Spence Adams

Sarah Spence Adams

Quaternion orthogonal designs (QODs) have been previously introduced as a basis for orthogonal space-time polarization block codes (OSTPBCs). This note will serve to correct statements concerning the optimality of a decoupled maximum-likelihood (ML) decoding algorithm. It will be shown that when compared to coupled decoding, the decoupled decoding is only optimal in certain cases. This raises several open problems concerning the decoding of OSTPBCs.


Giant Sequoia Insect, Disease, And Ecosystem Interactions, Douglas D. Piirto Dec 2008

Giant Sequoia Insect, Disease, And Ecosystem Interactions, Douglas D. Piirto

Douglas D. Piirto

Individual trees of giant sequoia (Sequoia gigantea [Lindl.] Decne.) have demonstrated a capacity to attain both a long life and very large size. It is not uncommon to find old-growth giant sequoia trees in their native range that are 1,500 years old and over 15 feet in diameter at breast height. The ability of individual giant sequoia trees to survive over such long periods of time has often been attributed to the species high resistance to disease, insect, and fire damage. Such a statement, however, is a gross oversimplification, given broader ecosystem and temporal interactions. For example, why isn't there …


Efficacy Of Herbicide Application Methods Used To Control Tanoak (Lithocarpus Densiflorus) In An Uneven-Aged Coast Redwood Management Context, Douglas D. Piirto, Brenda Smith, Eric K. Huff, Scott T. Robinson Dec 2008

Efficacy Of Herbicide Application Methods Used To Control Tanoak (Lithocarpus Densiflorus) In An Uneven-Aged Coast Redwood Management Context, Douglas D. Piirto, Brenda Smith, Eric K. Huff, Scott T. Robinson

Douglas D. Piirto

Three methods of tanoak (Lithocarpus densiflorus [Hook. & Arn.] Rehd.) control involving the application of the amine or ester form of triclopyr were evaluated in this coast redwood uneven-aged forest management study of herbicides. A cut-stump application with the amine form of triclopyr (Garlon 3A), frill cut with the amine form of triclopyr, basal-bark (outer surface) with the ester form of triclopyr (Garlon 4), and an untreated control were replicated three times. The tanoak control results in Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco) and/ or coast redwood (Sequoia sempervirens [D. Don] Endl.) predominated stands obtained in earlier studies …


Cost-Effective Fire Management For Southern California's Chaparral Wilderness: An Analytical Procedure, Chris A. Childers, Douglas D. Piirto Dec 2008

Cost-Effective Fire Management For Southern California's Chaparral Wilderness: An Analytical Procedure, Chris A. Childers, Douglas D. Piirto

Douglas D. Piirto

Fire management has always meant fire suppression to the managers of the chaparral covered southern California National Forests. Today, Forest Service fire management programs must be cost effective, while wilderness fire management objectives are aimed at recreating natural fire regimes. A cost-effectiveness analysis has been developed to compare fire management options for meeting these objectives in California's chaparral wilderness. This paper describes the analytical procedure using examples from a study currently being conducted for the Los Padres National Forest, and discusses some preliminary results.


Enhancing The Face Of Service-Oriented Capabilities, Kym J. Pohl, Jens G. Pohl Jul 2008

Enhancing The Face Of Service-Oriented Capabilities, Kym J. Pohl, Jens G. Pohl

Jens G. Pohl

With today’s focus toward discoverable web services, Service-Oriented Architectures (SOA) are becoming increasingly prevalent. To support an effective interaction between services and their clientele, the sophistication of the interface, or face, such services present is of critical importance. Without a rich, expressive nature, such services struggle to satisfy the industry promises of reuse, composability, and reduced inter-component dependencies. Especially relevant for domain-oriented applications, services must present sufficient levels of expression to allow for an effective exchange of relevant context. Further, such communication should be offered in an asynchronous manner to promote both work flow efficiency and limited coupling. This paper …


The Round Table Model: A Web-Oriented, Agent-Based Approach To Decision-Support Applications, Kym J. Pohl, Jens G. Pohl Jul 2008

The Round Table Model: A Web-Oriented, Agent-Based Approach To Decision-Support Applications, Kym J. Pohl, Jens G. Pohl

Jens G. Pohl

Not unlike King Arthur relying on the infamous Round Table as the setting for consultation with his most trusted experts, agent-based, decision-support systems provide human decision makers with a means of solving complex problems through collaboration with collections of both human and computer-based expert agents. The Round Table Framework provides a formalized architecture together with a set of development and execution tools which can be utilized to design, develop, and execute agent-based, decision-support applications. Based on a three-tier architecture, Round Table incorporates forefront technologies including distributed-object servers, inference engines, and web-based presentation to provide a framework for collaborative, agent-based decision …


Data, Information, And Knowledge In The Context Of Sils, Michael A. Zang, Jens G. Pohl Jul 2008

Data, Information, And Knowledge In The Context Of Sils, Michael A. Zang, Jens G. Pohl

Jens G. Pohl

Data, information, and knowledge are becoming increasingly common terms in the literature of the software industry. This terminology originated some time ago in the disciplines of cognitive science and artificial intelligence to reference three closely related but distinct concepts. Traditionally, mainstream software engineering has lumped all three concepts together as data and has only recently begun to distinguish between them. Unfortunately, the popular desire to distinguish between data, information, and knowledge within the mainstream has blurred the individual meanings of the words to the point where there is no longer a clear-cut distinction between them for most people. This problem …


Knowledge Management Enterprise Services (Kmes): Concepts And Implementation Principles, Jens G. Pohl Apr 2008

Knowledge Management Enterprise Services (Kmes): Concepts And Implementation Principles, Jens G. Pohl

Jens G. Pohl

The purpose of this paper is to present concepts and implementation principles related to the design and development of reusable software services that are capable of assisting users at the operational level. Knowledge Management Enterprise Services (KMES) are an implementation of the service-oriented architecture paradigm, with a focus on the exchange of data within the meaningful context of a particular application (i.e., knowledge) domain. This requires a KMES service to incorporate a high level representation of this knowledge domain in the form of an ontology that is shared among all collaborating services within the application environment and at the same …


Processing Small Quantities Of Walnut Logs For Lumber And Craft Items, Douglas D. Stokke, Peter Y. S. Chen, J. W. Van Sambeek Jan 1997

Processing Small Quantities Of Walnut Logs For Lumber And Craft Items, Douglas D. Stokke, Peter Y. S. Chen, J. W. Van Sambeek

Douglas D. Stokke

Many walnut plantation owners and woodworking hobbyists would like to process small quantities of walnut logs into lumber and discs for furniture and craft items. Various options exist for sawing, drying, and processing small diameter or short logs into lumber and cross-sectional discs. Portable band saws are a safe and inexpensive log breakdown option to commercial headsaw mills. Processing using the saw-dry-rip method will yield higher quantities of usable lumber from small diameter logs than the conventional saw-rip-dry method. Small quantities of lumber and discs can be inexpensively air dried under shelters or open sheds followed by approximately 15 to …


The Silviculture-Wood Quality Connection In Eastern Black Walnut, Douglas D. Stokke, Bruce E. Cutter, John E. Phelps Jan 1997

The Silviculture-Wood Quality Connection In Eastern Black Walnut, Douglas D. Stokke, Bruce E. Cutter, John E. Phelps

Douglas D. Stokke

The known effects of silvicultural practices on eastern black walnut (Juglans nigra L.) wood quality are reviewed. Since desirable quality differs from end user to end user, no specific recommendations are made.


Risk Analysis Of Black Walnut And Red Oak Plantations, Douglas D. Stokke, Stephen H. Kolison Jr., Jianbang Gan Jan 1997

Risk Analysis Of Black Walnut And Red Oak Plantations, Douglas D. Stokke, Stephen H. Kolison Jr., Jianbang Gan

Douglas D. Stokke

Risks and uncertainties are prevalent in timber production due to the nature and length of the production process. This paper examines the volatility of timber prices and the effects of some economic uncertainties and risks such as fluctuations in timber prices and the interest rate on the economic returns of black walnut and red oak plantations. Historical patterns of timber prices for black walnut and oaks are investigated and compared with those of other timber species and stock price. The sensitivity of economic returns from black walnut and red oak plantations to changes in timber prices and the discount rate …


Influence Of Geographic Origin And Soil Properties On Color Of Black Walnut Veneer, Douglas D. Stokke, Edward C. Workman Jr., John E. Phelps, Felix Ponder Jr. Jan 1997

Influence Of Geographic Origin And Soil Properties On Color Of Black Walnut Veneer, Douglas D. Stokke, Edward C. Workman Jr., John E. Phelps, Felix Ponder Jr.

Douglas D. Stokke

Walnut veneer frorn sites in Missouri, Illinois, and Indiana was analyzed for color attributes and chemical properties. Veneer color also was compared to an industry color standard. Soil chemical and physical properties were measured on selected sites in each state. In general, walnut trees grown on soils with equal proportions of sand, silt, and clay have better veneer color attributes than trees grown on soils with high clay I sand or clay I silt ratios.


Lignin Distribution In Thermomechanically Pulped Wood Fibers Via X-Ray Microanalysis, Douglas Stokke, Xuerong Wang Jan 1991

Lignin Distribution In Thermomechanically Pulped Wood Fibers Via X-Ray Microanalysis, Douglas Stokke, Xuerong Wang

Douglas D. Stokke

The three major framework organic constituents of the secondary xylem (wood) of trees are cellulose, hemicelluloses, and lignin. Lignin imparts a number of important physical properties to the woody cell wall. In addition, lignin serves as the "cement" which binds cells together, and is the material which must be softened, altered, or removed during pulping processes. The distribution of lignin within pulp cell walls is of importance with respect to use of the pulp fibers. In this study, x-ray analysis was used to investigate lignin distribution in thermomechanically pulped (i.e., pulped with heat and pressure, with no chemical treatment) aspen …


Sem Views Of Oak Wood, Douglas D. Stokke Jan 1986

Sem Views Of Oak Wood, Douglas D. Stokke

Douglas D. Stokke

The anatomical structure of the secondary xylem (wood) of trees varies with location in the tree. The size, shape, and distribution of cell types varies not only between locations (i.e., stem vs. branch vs. root), but also within an annual ring or across annual rings at a given cross-sectional plane.