Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons

Open Access. Powered by Scholars. Published by Universities.®

1998

Discipline
Institution
Keyword
Publication
Publication Type
File Type

Articles 1501 - 1530 of 2574

Full-Text Articles in Physical Sciences and Mathematics

Arginine To Glutamine Substitutions In The Fourth Module Of Xenopus Interphotoreceptor Retinoid-Binding Protein, Mark S. Braiman, Claxton A. Baer, Ellen E. Van Niel, Jeffrey W. Cronk, Michael T. Kinter, Nicholas E. Sherman, Federico Gonzalez-Fernandez Jan 1998

Arginine To Glutamine Substitutions In The Fourth Module Of Xenopus Interphotoreceptor Retinoid-Binding Protein, Mark S. Braiman, Claxton A. Baer, Ellen E. Van Niel, Jeffrey W. Cronk, Michael T. Kinter, Nicholas E. Sherman, Federico Gonzalez-Fernandez

Chemistry - All Scholarship

Interphotoreceptor retinoid-binding protein (IRBP) is unusual for a lipid-binding protein in that its gene is expressed uniquely by cells of photoreceptor origin and consists of four homologous repeats, each coding for a module of~300 amino acid residues. All-trans retinol binding domains, which appear to be present in each module, are composed of conserved hydrophobic regions [Baer et al, Exp Eye Res 1998; 66:249-262]. Here we investigate the role of highly conserved arginines contained in these regions.


Verification And Validation Of Simulation Models, Robert G. Sargent Jan 1998

Verification And Validation Of Simulation Models, Robert G. Sargent

Electrical Engineering and Computer Science - All Scholarship

This paper discusses verification and validation of simulation models. The different approaches to deciding model validity are presented; how model verification and validation relate to the model development process are discussed; various validation techniques are defined; conceptual model validity, model verification, operational validity, and data validity are described; ways to document results are given; and a recommended procedure is presented.


A Global Communication Optimization Technique Based On Data-Flow Analysis And Linear Algebra, Mahmut Kandemir, P. Banerjee, Alok Choudhary, J. Ramanujam Jan 1998

A Global Communication Optimization Technique Based On Data-Flow Analysis And Linear Algebra, Mahmut Kandemir, P. Banerjee, Alok Choudhary, J. Ramanujam

Electrical Engineering and Computer Science - All Scholarship

Reducing communication overhead is extremely important in distributed-memory message-passing architectures. In this paper, we present a technique to improve communication that considers data access patterns of the entire program. Our approach is based on a combination of traditional data-flow analysis and a linear algebra framework, and works on structured programs with conditional statements and nested loops but without arbitrary goto statements. The distinctive features of the solution are the accuracy in keeping communication set information, support for general alignments and distributions including block-cyclic distributions and the ability to simulate some of the previous approaches with suitable modifications. We also show …


Clouds: A Decision Tree Classifier For Large Datasets, Khaled Alsabti, Sanjay Ranka, Vineet Singh Jan 1998

Clouds: A Decision Tree Classifier For Large Datasets, Khaled Alsabti, Sanjay Ranka, Vineet Singh

Electrical Engineering and Computer Science - All Scholarship

Classification for very large datasets has many practical applications in data mining. Techniques such as discretization and dataset sampling can be used to scale up decision tree classifiers to large datasets. Unfortunately, both of these techniques can cause a significant loss in accuracy. We present a novel decision tree classifier called CLOUDS, which samples the splitting points for numeric attributes followed by an estimation step to narrow the search space of the best split. CLOUDS reduces computation and I/O complexity substantially compared to state of the art classifiers, while maintaining the quality of the generated trees in terms of accuracy …


Design, Implementation, And Evaluation Of Parallell Pipelined Stap On Parallel Computers, Alok Choudhary, Wei-Keng Liao, Donald Weiner, Pramod Varshney, Richard Linderman, Mark Linderman Jan 1998

Design, Implementation, And Evaluation Of Parallell Pipelined Stap On Parallel Computers, Alok Choudhary, Wei-Keng Liao, Donald Weiner, Pramod Varshney, Richard Linderman, Mark Linderman

Electrical Engineering and Computer Science - All Scholarship

Performance results are presented for the design and implementation of parallel pipelined space-time adaptive processing (STAP) algorithms on parallel computers. In particular, the issues involved in parallelization, our approach to parallelization, and performance results on an Intel Paragon are described. The process of developing software for such an application on parallel computers when latency and throughput are both considered together is discussed and tradeoffs considered with respect to inter and intratask communication and data redistribution are presented. The results show that not only scalable performance was achieved for individual component tasks of STAP but linear speedups were obtained for the …


Adaptive Linkage Crossover, Ayed A. Salman, Kishan Mehrotra, Chilukuri K. Mohan Jan 1998

Adaptive Linkage Crossover, Ayed A. Salman, Kishan Mehrotra, Chilukuri K. Mohan

Electrical Engineering and Computer Science - All Scholarship

Problem-specific knowledge is often implemented in search algorithms using heuristics to determine which search paths are to be explored at any given instant. As in other search methods, utilizing this knowledge will more quickly lead a genetic algorithm (GA) towards better results. In many problems, crucial knowledge is not found in individual components, but in the interrelations between those components. For such problems, we develop an interrelation (linkage) based crossover operator that has the advantage of liberating GAs from the constraints imposed by the fixed representations generally chosen for problems. The strength of linkages between components of a chromosomal structure …


A Multithreaded Message-Passing System For High Performance Distributed Computing Applications, Sung-Yong Park, Joohan Lee, Salim Hariri Jan 1998

A Multithreaded Message-Passing System For High Performance Distributed Computing Applications, Sung-Yong Park, Joohan Lee, Salim Hariri

Electrical Engineering and Computer Science - All Scholarship

High Performance Distributed Computing (HPDC) applications require low-latency and high-throughput communication services and HPDC applications have different Quality of Service (QOS) requirements (e.g., bandwidth requirement, flow/error control algorithms, etc.). The communication services provided by traditional message-passing systems are fixed and thus can not be changed to meet the requirements of different HPDC applications. NYNET (ATM wide area network testbed in New York state) Communication System (NCS) is a multithreaded message-passing system developed at Syracuse University that provides high-performance and flexible communication services. In this paper, we overview the general architecture of NCS and present how NCS communication services are implemented. …


Steady State Memetic Algorithm For Partial Shape Matching, Ender Ozcan, Chilukuri K. Mohan Jan 1998

Steady State Memetic Algorithm For Partial Shape Matching, Ender Ozcan, Chilukuri K. Mohan

Electrical Engineering and Computer Science - All Scholarship

Shape matching techniques are important in machine intelligence, especially in applications such as robotics. Currently, there are three major approaches to shape recognition: statistical, syntactic and neural approaches. This paper presents a fourth approach: evolutionary algorithms. A steady state memetic algorithm is shown to be successful in matching shapes even when they are partially obscured, and even in the presence of noise in the input image.


Integrating Security Into The Curriculum, Cynthia E. Irvine, Shiu-Kai Chin, Deborah Frincke Jan 1998

Integrating Security Into The Curriculum, Cynthia E. Irvine, Shiu-Kai Chin, Deborah Frincke

Electrical Engineering and Computer Science - All Scholarship

The number of skilled practitioners of computer security who are able to address the complexities of modern technology and are familiar with successful approaches to system security is very small. People want security but are faced with two difficulties. First, they do not know how to achieve it in the context of their enterprises. They may not even know of a way to translate organizational procedures into policies, much less implement a set of mechanisms to enforce those policies. Second, they have no way of knowing whether their chosen mechanisms are effective. The recent US Presidential Commission on Critical Infrastructure …


Partial Shape Matching Using Genetic Algorithms, Ender Ozcan, Chilukuri K. Mohan Jan 1998

Partial Shape Matching Using Genetic Algorithms, Ender Ozcan, Chilukuri K. Mohan

Electrical Engineering and Computer Science - All Scholarship

Shape recognition is a challenging task when images contain overlapping, noisy, occluded, partial shapes. This paper addresses the task of matching input shapes with model shapes described in terms of features such as line segments and angles. The quality of matching is gauged using a measure derived from attributed shape grammars. We apply genetic algorithms to the partial shape-matching task. Preliminary results, using model shapes with 6 to 70 features each, are extremely encouraging.


The Design And Evaluation Of A Virtual Distributed Computing Environment, Haluk Topcuoglu, Salim Hariri, Dongmin Kim, Yoonhee Kim, Xue Bing Jan 1998

The Design And Evaluation Of A Virtual Distributed Computing Environment, Haluk Topcuoglu, Salim Hariri, Dongmin Kim, Yoonhee Kim, Xue Bing

Electrical Engineering and Computer Science - All Scholarship

In this paper we present the Virtual Distributed Computing Environment (VDCE), a metacomputing environment currently being developed at Syracuse University. VDCE provides an efficient web-based approach for developing, evaluating and visualizing large-scale distributed applications that are based on predefined task libraries on diverse platforms. The VDCE task libraries relieve end-users of tedious task implementations and also support reusability. The VDCE software architecture is described in terms of three modules: a) the Application Editor, a user-friendly application development environment that generates the Application Flow Graph (AFG) of an application; b) the Application Scheduler, which provides an efficient task-to-resource mapping of AFG; …


An Efficient Parallel Algorithm For High Dimensional Similarity Join, Khaled Alsabti, Sanjay Ranka, Vineet Singh Jan 1998

An Efficient Parallel Algorithm For High Dimensional Similarity Join, Khaled Alsabti, Sanjay Ranka, Vineet Singh

Electrical Engineering and Computer Science - All Scholarship

Multidimensional similarity join finds pairs of multi-dimensional points that are within some small distance of each other: The 6-k-d-B tree has been proposed as a data structure that scales better as the number of dimensions in-creases compared to previous data structures. We present a cost model of the E-k-d-B tree and use it to optimize the leaf size. We present novel parallel algorithms for the similarity join using the E-k-d-B tree. A load-balancing strategy based on equi-depth histograms is shown to work well for uniform or low-skew situations, whereas another based on weighted equi-depth histograms works far better for high-skew …


Secure Delegation For Distributed Object Environments, Nataraj Nagaratnam, Doug Lea Jan 1998

Secure Delegation For Distributed Object Environments, Nataraj Nagaratnam, Doug Lea

Electrical Engineering and Computer Science - All Scholarship

SDM is a Secure Delegation Model for Java-based distributed object environments. SDM extends current Java security features to support secure remote method invocations that may involve chains of delegated calls across distributed objects. The framework supports a control API for application developers to specify mechanisms and security policies surrounding simple or cascaded delegation. Delegation may also be disabled and optionally revoked. These policies may be controlled explicitly in application code, or implicitly via administrative tools.


A Problem Solving Environment For Network Computing, Salim Hariri, Haluk Topcuoglu, Wojtek Furmanski, Dongmin Kim, Yoonhee Kim Jan 1998

A Problem Solving Environment For Network Computing, Salim Hariri, Haluk Topcuoglu, Wojtek Furmanski, Dongmin Kim, Yoonhee Kim

Electrical Engineering and Computer Science - All Scholarship

The current advances in high-speed networks and WWW technologies have made network computing a cost-effective high performance computing environment. New software development models and problem solving environments must be developed to utilize the network computing environment efficiently. In this paper we present Virtual Distributed Computing Environment (VDCE), which provides a problem solving environment for high-performance distributed computing over wide-area networks. VDCE enables scientists to develop distributed applications without knowing the detailed architecture of the underlying resources. VDCE provides well-defined library functions that relieve end users from tedious task implementations and it supports software reusability. The VDCE software architecture consists of …


Automatic Granularity Control For Load Balancing Of Concurrent Particle Simulations, Marc Rieffel, Stephen Taylor, Jerrell Watts Jan 1998

Automatic Granularity Control For Load Balancing Of Concurrent Particle Simulations, Marc Rieffel, Stephen Taylor, Jerrell Watts

Electrical Engineering and Computer Science - All Scholarship

This paper demonstrates the use of automatic granularity control as part of dynamic load balancing for irregular, particle-based simulations. Performance optimization techniques are considered in the context of a concurrent Direct Simulation Monte Carlo method used to study the rarefied gas flow inside three-dimensional plasma reactors. Several computational techniques are used to reduce the overall time to deliver realistic threedimensional results. The effectiveness of dynamic load balancing and granularity control are presented for large-scale simulations on distributed-memory multicomputers.


Automatic Granularity Control For Load Balancing Of Concurrent Particle Simulations, Marc Rieffel, Stephen Taylor, Jerrell Watts Jan 1998

Automatic Granularity Control For Load Balancing Of Concurrent Particle Simulations, Marc Rieffel, Stephen Taylor, Jerrell Watts

Electrical Engineering and Computer Science - All Scholarship

This paper demonstrates the use of automatic granularity control as part of dynamic load balancing for irregular, particle-based simulations. Performance optimization techniques are considered in the context of a concurrent Direct Simulation Monte Carlo method used to study the rarefied gas flow inside three-dimensional plasma reactors. Several computational techniques are used to reduce the overall time to deliver realistic threedimensional results. The effectiveness of dynamic load balancing and granularity control are presented for large-scale simulations on distributed-memory multicomputers.


Performance Enhancement Using Intra-Server Caching In A Continuous Media Server, Chutimet Srinilta, Alok Choudhary Jan 1998

Performance Enhancement Using Intra-Server Caching In A Continuous Media Server, Chutimet Srinilta, Alok Choudhary

Electrical Engineering and Computer Science - All Scholarship

Continuity of stream playback is the crucial constraint in designing a continuous media server. From a distributed memory architectural model developed earlier, we found that there were many points where the stream capacity of the server could be improved. The stream capacity was usually limited by the storage bottlenecks. Serving streams from memory cache eliminates disk accesses and data transfers between nodes which, in turn, helps relieve those bottlenecks. However, the capacity of the server ultimately depends on client access pattern. Client request assignment has an impact on cache hit ratio as well as workload distribution. It is also the …


The Probe, Issue 184 – January 1998 Jan 1998

The Probe, Issue 184 – January 1998

The Probe: Newsletter of the National Animal Damage Control Association

NADCA Election Results!
PRESIDENT Robert H. Giles, Jr. (VA) VICE PRESIDENT - WEST Mark Collinge (ID) VICE PRESIDENT - EAST Pete Butchko (MS) SECRETARY Richard B. Chipman (VT) TREASURER Grant Huggins (OK)
REGIONAL DIRECTORS: Western (1): Diane deLorimier (CA) Southern Rockies (2): GaryWitmer (CO) Northern Rockies (3): George E. Graves (ID) South Central (4): James R. Gallaspy (LA) North Central (5): James C. Luchsinger (NE) Great Lakes (6): Mike Dwyer (OH) Northeastern (7): Jerry L. Pickel (PA) Centraleastern (8): JohnM. Houben (VA) Southeastern (9): D. Tommy King (MS)
From Our Incoming President: An Opinion....-- Robert H. Giles, Jr.
Carrie Hunt …


Canadian Cooperative Wildlife Health Centre, Volume 5-3, Winter 1998 Jan 1998

Canadian Cooperative Wildlife Health Centre, Volume 5-3, Winter 1998

Canadian Cooperative Wildlife Health Centre: Newsletters and Publications

Quebec Pathologist
Italian Conference
A Critical Need for Information on Diseases of Wild Amphibians
Update on Zoonoses(Chlamydiaand Hanta Virus)
Listeriosis in a Canada goose
Bowhead whale stranding on the northeast coast of Newfoundland
Diseases of beluga whales from the St. Lawrence Estuary: 1998
Syngamiasias in an American robin
Lead poisoning in Canada geese due to skeet shot ingestion
Canine distemper virus in raccoons and striped skunks
Oral masses in Mourning doves
Hairless Grey Squirrels
Chronic wasting disease in a game farm elk in Saskatchewan
Toxoplasmosis in a merlin
Botulism losses in 1998
Avian Cholera in double-crested cormorants


Mea Culpa: Formal Education And The Dis-Integrated World., Brian P. Coppola, Douglas S. Daniels Jan 1998

Mea Culpa: Formal Education And The Dis-Integrated World., Brian P. Coppola, Douglas S. Daniels

Chemistry Faculty Publications

Formal education has removed itself so far from any truly integrated view of the Natural World that fragmentation and certainty are prevailing ethics. Technological progress has resulted in increased specialization within academic disciplines and their concurrent separation from each other. Knowledge is extracted from a fully integrated world, but is examined and defined by the 'dis-integrated' objectives.


High-Resolution Image Reconstruction From A Sequence Of Rotated And Translated Frames And Its Application To An Infrared Imaging System, Russell C. Hardie, Kenneth J. Barnard, John G. Bognar, Ernest E. Armstrong, Edward A. Watson Jan 1998

High-Resolution Image Reconstruction From A Sequence Of Rotated And Translated Frames And Its Application To An Infrared Imaging System, Russell C. Hardie, Kenneth J. Barnard, John G. Bognar, Ernest E. Armstrong, Edward A. Watson

Electrical and Computer Engineering Faculty Publications

Some imaging systems employ detector arrays that are not sufficiently dense to meet the Nyquist criterion during image acquisition. This is particularly true for many staring infrared imagers. Thus, the full resolution afforded by the optics is not being realized in such a system. This paper presents a technique for estimating a high-resolution image, with reduced aliasing, from a sequence of undersampled rotated and translationally shifted frames. Such an image sequence can be obtained if an imager is mounted on a moving platform, such as an aircraft. Several approaches to this type of problem have been proposed in the literature. …


Attitude Measurement, Mark A. Stedham, Partha P. Banerjee, Seiji Nishifuji, Shogo Tanaka Jan 1998

Attitude Measurement, Mark A. Stedham, Partha P. Banerjee, Seiji Nishifuji, Shogo Tanaka

Electrical and Computer Engineering Faculty Publications

In many practical situations, it is important to determine and measure the attitude of a particular vehicle, such as a ship, an airplane, a piece of mechanical equipment such as a, crane lifter, or a spacecraft. For this reason, many attitude sensors have been developed with advanced computer and semiconductor technologies. This section first introduces the various attitude sensors with an explanation of their operating principles and then presents several methodologies for attitude measurement and determination, including ships and crane lifters, aircraft, and spacecraft applications.


Quartzite Fabric Transition In A Cordilleran Metamorphic Core Complex, Allen J. Mcgrew, Martin Casey Jan 1998

Quartzite Fabric Transition In A Cordilleran Metamorphic Core Complex, Allen J. Mcgrew, Martin Casey

Geology Faculty Publications

Photomicrographs 143A-143F record fabric variations in quartzite with increasing structural depth in a > 1 km thick, amphibolite-facies, normal-sense shear zone in the East Humboldt metamorphic core complex, Nevada (Figure 143.1). This shear zone and the overlying detachment system unroofed an infrastructure of high-grade, migmatitic gneiss during Oligocene to early Miocene extension (Dallmeyer and others, 1986; Wright and Snoke, 1993; McGrew and Snee, 1994). Thermobarometric constraints from near the base of the mylonitic zone record deformation conditions of 550°- 620°C and 300-400 MPa (Hurlow and others, 1991). Sample WBC6 (l43A and 143B) characterizes the mylonitic zone, whereas sample 8706-1 (143C and …


Physical Dependence Of The Sensitivity And Room-Temperature Stability Of Auxge1-X Thin Film Resistive Thermometers On Annealing Conditions, Nathanael A. Fortune, Michael J. Graf, Keizo Murata Jan 1998

Physical Dependence Of The Sensitivity And Room-Temperature Stability Of Auxge1-X Thin Film Resistive Thermometers On Annealing Conditions, Nathanael A. Fortune, Michael J. Graf, Keizo Murata

Physics: Faculty Publications

The reported nearly constant temperature sensitivity of appropriately annealed polycrystalline AuxGe1-x thin films at cryogenic temperatures would appear to make them promising materials for low mass, rapid thermal response resistive thermometers, but their adoption has been limited by difficulties in fabrication and uncertainties in annealing. In this work, we present a method of fabrication and annealing which allows control of the two most important parameters for these films: the room-temperature resistivity ρRT and the temperature sensitivity η(T), where η ≡ -d In R/d In T. We find that the dependence of ρRT on total anneal duration t for x≈0.18 is …


A Kinetic Study Of The Photolysis Of Ethylferrocene In Chloroform, Son L. Phan, Patrick E. Hoggard Jan 1998

A Kinetic Study Of The Photolysis Of Ethylferrocene In Chloroform, Son L. Phan, Patrick E. Hoggard

Chemistry and Biochemistry

The photooxidation of ethylferrocene to ethylferricinium ion and tetrachloroferrate in CHCl3 under 254 nm irradiation proceeds through light absorption by both ethylferrocene and chloroform. The products remain in solution at concentrations below 10-3 M. The fraction occurring through a solvent-initiated pathway increases during the course of the reaction. A secondary thermal reaction is responsible for generating tetrachloroferrate from ethylferricinium ion. The rate of the reaction increases during the early stages, and the data throughout the course of the reaction are consistent with the rate law ( afs + bfR)/ (1 + c[R]/[P]-d[R]/[Cl ]), where [R] and [P] are the concentrations …


Santa Clara Magazine, Volume 39 Number 4, Winter 1998, Santa Clara University Jan 1998

Santa Clara Magazine, Volume 39 Number 4, Winter 1998, Santa Clara University

Santa Clara Magazine

10 - INSIDE OUT Francisco Jimenez, chairman of the University's Modern Languages and Literatures Department, recalls his grade-school days and immigrant family.

14 - FROM HALLOWED TO HIP Connie Hinckley, East Bay writer, examines the media's many-faceted portrayals of the priesthood, especially the controversial Father Ray of Nothing Sacred.

20 - SANTA CLARA'S ADOBE LEGACY Susan Vogel, San Francisco author and publisher, traces the history of the Adobe Lodge and describes its many roles in the life of the University.

26 - UNCOVERING THE REGION'S RICH PAST As the University clears land for new buildings, SCU archeologists and Native American …


Editorial Board & Iowa Academy Of Science Officers And Directors Jan 1998

Editorial Board & Iowa Academy Of Science Officers And Directors

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Iowa's Changing Forest Resources, Steven E. Jungst, Donald R. Farrar, Michael Brandrup Jan 1998

Iowa's Changing Forest Resources, Steven E. Jungst, Donald R. Farrar, Michael Brandrup

Journal of the Iowa Academy of Science: JIAS

After a period of decline in area extending from the 1850s to 1974, Iowa's forest area increased between 1974 and 1990. Although the area increase is encouraging, it may be fleeting. In addition, changes in forest stand structure and forest ownership patterns along with other pressures may make it difficult to maintain healthy forest ecosystems in the future. Notes from the original land survey in Iowa coupled with information from U.S. Forest Service forest inventories make it possible to look at changes in forest area and forest tree types. Unfortunately, similar long-term data do not exist to make possible a …


Hydrogen And Oxygen Isotope Fractionation Between Brucite And Aqueous Nacl Solutions From 250 To 450°C, Peter Saccocia, J. S. Seewald, W. C. Shanks Iii Jan 1998

Hydrogen And Oxygen Isotope Fractionation Between Brucite And Aqueous Nacl Solutions From 250 To 450°C, Peter Saccocia, J. S. Seewald, W. C. Shanks Iii

Geological Sciences Faculty Publications

Hydrogen and oxygen isotope fractionation factors between brucite and aqueous NaCl solutions (1000lnαbr-sw) have been calibrated by experiment from 250 to 450°C at 0.5 Kb. For D/H fractionation, 1000lnα br-sw values are as follows: −32 ± 6‰ (250°C, 3.2 wt% NaCl), −21 ± 2‰ (350°C, 10.0 wt% NaCl), and −22 ± 2‰ (450°C, 3.2 wt% NaCl), indicating that brucite is depleted in D relative to coexisting aqueous NaCl solutions. These results are in good agreement with previous D/H fractionation factors determined in the brucite-water system, indicating that any effects of dissolved salt on D/H fractionation are relatively small, …


Front Matter Jan 1998

Front Matter

Journal of the Minnesota Academy of Science

No abstract provided.