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2003

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Communicating With Microwave-Propelled Sails, Chaouki T. Abdallah, I. Sezi Bakim, Edl Schamiloglu Aug 2003

Communicating With Microwave-Propelled Sails, Chaouki T. Abdallah, I. Sezi Bakim, Edl Schamiloglu

Electrical & Computer Engineering Faculty Publications

We describe a communication channel for a microwave-propelled sail, a novel concept for a deep-space scientific probe. We suggest techniques to recover the great loss introduced by the large distances, and we have conducted various simulations to understand the effects on the performance of the system. Possible disruption in the channel by high-energy solar flares, which increase the error in the estimation of the received signal, is accounted for. We developed the simulation for a full communication system on an additive white Gaussian noise (AWGN) channel, including the random-time solar-flare disturbance. We show that turbo codes can be exploited that …

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Factors Influencing The Adoption Of E-Marketplaces By Small Organizations: An Empirical Investigation, Xin Tan, Fiona Fui-Hoon Nah, Charalambos Iacovou, Jaekyung. Kim Aug 2003

Factors Influencing The Adoption Of E-Marketplaces By Small Organizations: An Empirical Investigation, Xin Tan, Fiona Fui-Hoon Nah, Charalambos Iacovou, Jaekyung. Kim

Research Collection School Of Computing and Information Systems

The emergence of mobile computing combined with the increased popularity of the Internet is changing our daily lives. The increasing use of small portable computers, wireless networks and satellites un folds the new technology of mobile computing, which allows transmis sion of data to computers that are not physically linked to a network. As a result, people can communicate on the move. Mobile devices with new input and output methods and form factors are dramatically different from traditional desktop computers (Rodden et al., 1998). These technological changes make increasing demands on both the quality of user interface and the functionality …

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Information Systems Requirements Determination And Analysis: A Mental Modeling Approach, Keng Siau, X. Tan Aug 2003

Information Systems Requirements Determination And Analysis: A Mental Modeling Approach, Keng Siau, X. Tan

Research Collection School Of Computing and Information Systems

Regardless of the system development methodology adopted, being able to understand users’ informationrequirements is vital to the success of an information systems project. The intrinsic communications obstaclesexist within an individual user, among users, and between users and systems analysts. Different requirementsdetermination and analysis (RDA) techniques have been widely used with different outcomes. Some limitations of these techniques can be identified. In this paper, we propose a mental modeling approach to support RDA. Popular in other disciplines, mental modeling techniques have some distinct advantages to overcome some intrinsic communication obstacles in RDA, and to complement other techniques.

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The Effect Of Domain Knowledge On Icon Visualization, Keng Siau, Fiona Fui-Hoon Nah Aug 2003

The Effect Of Domain Knowledge On Icon Visualization, Keng Siau, Fiona Fui-Hoon Nah

Research Collection School Of Computing and Information Systems

Iconic interfaces are now the de facto interface for most computer systems. Despite the popularity of iconic interfaces and the widespread belief that iconic interfaces are easier to comprehend than non-iconic interfaces, we have not come across any published study that has examined the effect of domain knowledge on end users’ interpretation of icons. An understanding of the relationship between domain knowledge and its effect on interpretation will enable us to design better icons to not only facilitate end users’ interpretation but also reduce misinterpretations of icons. This paper reports on an experimental study that investigates the effect of domain …

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Solving Multi-Objective Multi-Constrained Optimization Problems Using Hybrid Ants System And Tabu Search, Hoong Chuin Lau, Min Kwang Lim, Wee Chong Wan, Hui Wang, Xiaotao Wu Aug 2003

Solving Multi-Objective Multi-Constrained Optimization Problems Using Hybrid Ants System And Tabu Search, Hoong Chuin Lau, Min Kwang Lim, Wee Chong Wan, Hui Wang, Xiaotao Wu

Research Collection School Of Computing and Information Systems

Many real-world optimization problems today are multi-objective multi-constraint generalizations of NP-hard problems. A classic case we study in this paper is the Inventory Routing Problem with Time Windows (IRPTW). IRPTW considers inventory costs across multiple instances of Vehicle Routing Problem with Time Windows (VRPTW). The latter is in turn extended with time-windows constraints from the Vehicle Routing Problem (VRP), which is extended with optimal fleet size objective from the single-objective Traveling Salesman Problem (TSP). While single-objective problems like TSP are solved effectively using meta-heuristics, it is not obvious how to cope with the increasing complexity systematically as the problem is …

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Faculty Senate Senate Membership, 2003-2004, Vol 31, P 7, Unm Faculty Senate Aug 2003

Faculty Senate Senate Membership, 2003-2004, Vol 31, P 7, Unm Faculty Senate

Faculty Senate Documents

No abstract provided.

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Consensus-Based Table Form Recognition, William A. Barrett, Heath E. Nielson Aug 2003

Consensus-Based Table Form Recognition, William A. Barrett, Heath E. Nielson

Faculty Publications

Zoning documents increases the resolution of indexing from the image level to the field level. A line-delimited tabular document forms a well defined series of regions. However, as image quality decreases, accurate zoning becomes increasingly difficult. Given a sequence of documents with the same layout, we present a robust zoning method which exploits both intra- and inter-document consensus to form a more accurate combined result (template) that can be applied to any other document with the same layout.

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Just-In-Time Browsing For Digitized Microfilm And Other Similar Image Collections, William A. Barrett, Douglas J. Kennard Aug 2003

Just-In-Time Browsing For Digitized Microfilm And Other Similar Image Collections, William A. Barrett, Douglas J. Kennard

Faculty Publications

This paper describes “Just-In-Time Browsing” (JITB), a method for image browsing (at modem-like speed) in which image data is transmitted and presented to the user progressively, in prioritized order, based on image content and user interaction. Spatial resolution and grayscale or color fidelity is increased first for the portions of the image that are immediately of most interest to the user. JITB is specifically geared toward digitized microfilm and other similar document image collections, although it can also be used for other types of images. A series of common browsing tasks performed by multiple users demonstrates that JITB compares favorably …

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The Somewhat Flawed Theoretical Foundation Of The Extension Service, Garry Stephenson Aug 2003

The Somewhat Flawed Theoretical Foundation Of The Extension Service, Garry Stephenson

Journal of Extension

Innovation diffusion theory is the foundation of Extension agriculture outreach methods. The theory predicts that an innovation will initially be adopted by a small group of innovative farmers and later diffused to other farmers. Over the past 30 years, the theory has been criticized for favoring large wealthy farmers and increasing the inequities in rural areas. By utilizing innovation diffusion theory, have we caused harm to the population we serve? Because this theory has such an influence on our approach to outreach, why haven't we kept up with developments in the evolution of this theory? What can we change to …

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Modeling Of Short-Gap Esd Under Consideration Of Different Discharge Mechanisms, S. Bonisch, Wilifried Kalkner, David Pommerenke Aug 2003

Modeling Of Short-Gap Esd Under Consideration Of Different Discharge Mechanisms, S. Bonisch, Wilifried Kalkner, David Pommerenke

Electrical and Computer Engineering Faculty Research & Creative Works

Simulation of short gap electrostatic discharge (ESD) in air needs to consider two processes: a surface process and an avalanche process. Two models, a phenomenological approach and a physical approach, considering both discharge processes are proposed for the simulation of short-gap ESD. A new mathematical derivation for the modeling of the surface process is discussed in detail. A new technique to combine surface and avalanche process models is described. Measured and simulated data based on short-gap ESD are provided and compared. Advantages and drawbacks of the proposed models are discussed. Attained results should help to optimize ESD testing.

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Fdtd Method Capable Of Attaching Rectangular Domains, Kai Xiao, David Pommerenke, James L. Drewniak Aug 2003

Fdtd Method Capable Of Attaching Rectangular Domains, Kai Xiao, David Pommerenke, James L. Drewniak

Electrical and Computer Engineering Faculty Research & Creative Works

A finite-difference time-domain (FDTD) method capable of attaching rectangular computational domains is proposed herein. The aim of this approach is to reduce the size of computational domain according to the geometry of the modeled structure so as to reduce the simulation time with keeping precision of the result in an acceptable range. A multigrid algorithm is applied on the attaching interface between two rectangular domains so that different resolution can be achieved in different domains.

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Online Identification Of Turbogenerator's Dynamics Using A Neuro-Identifier, Wenxin Liu, Ganesh K. Venayagamoorthy, Donald C. Wunsch Aug 2003

Online Identification Of Turbogenerator's Dynamics Using A Neuro-Identifier, Wenxin Liu, Ganesh K. Venayagamoorthy, Donald C. Wunsch

Electrical and Computer Engineering Faculty Research & Creative Works

The increasing complexity of modern power systems highlights the need for effective system identification techniques for the successful control of power system. This paper proposes a robust continually online trained neuroidentifier to predict the outputs of turbogenerator - terminal voltage and speed deviation. The inputs to the neuro-identifier are the changes of the plant's outputs and plant's inputs. It overcomes the drawback of calculating deviation signals from reference signals for different operating points in previous work. Simulation results show that the neuro-identifier can provide accurate identification under different operating conditions. Furthermore, the neuro-identifier can learn the dynamics of the system …

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Quantifying The Effects On Emi And Si Of Source Imbalances In Differential Signaling, Chen Wang, James L. Drewniak Aug 2003

Quantifying The Effects On Emi And Si Of Source Imbalances In Differential Signaling, Chen Wang, James L. Drewniak

Electrical and Computer Engineering Faculty Research & Creative Works

Imbalances in differential signaling can introduce common-mode components, resulting in signal integrity (SI) problems as well as EMI problems. Three-port mixed-mode S-parameters are employed to quantify the impacts on EMI. The EMI problems caused by delay skew and slew rate skew are investigated.

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Solubility And Freezing Effects Of Fe2+ And Mg2+ In H2so4 Solutions Representative Of Upper Tropospheric And Lower Stratospheric Sulfate Particles, Matthew E. Wise, Sarah D. Brooks, Rebecca M. Garland, Daniel J. Cziczo, Scot T. Martin, Margaret A. Tolbert Jul 2003

Solubility And Freezing Effects Of Fe2+ And Mg2+ In H2so4 Solutions Representative Of Upper Tropospheric And Lower Stratospheric Sulfate Particles, Matthew E. Wise, Sarah D. Brooks, Rebecca M. Garland, Daniel J. Cziczo, Scot T. Martin, Margaret A. Tolbert

CUP Faculty Research

Chemical elements characteristic of earth minerals and meteorites are present within background tropospheric and stratospheric sulfate aerosol particles. However, it is unknown if these elements are present predominantly as solids, including possible sulfates, carbonates, and oxides, or rather as soluble aqueous metal ions or complexes. Further, it is unclear how these impurities could affect particle freezing. To address these questions, we have determined the total equilibrium metal solubility ([Fe2+]T and [Mg2+]T) in 20–90 wt % sulfuric acid solutions over the temperature range 200–300 K. We have measured solubilities using samples of MgSO4 …

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A National Crisis Or Localized Problems? Getting Perspective On The Scope And Scale Of The Teacher Shortage, Patrick Murphy, Michael Dearmond, Kacey Guin Jul 2003

A National Crisis Or Localized Problems? Getting Perspective On The Scope And Scale Of The Teacher Shortage, Patrick Murphy, Michael Dearmond, Kacey Guin

Education Policy Analysis Archives (EPAA)

Despite the considerable attention the popular press has devoted to the question of teacher shortages, there have been surprisingly few attempts to systematically measure the size and nature of the problem. This article attempts to estimate the size and nature of the celebrated teacher shortage of the late 1990s by using data from the U.S. Department of Education’s 1999-00 School and Staffing Survey. ...

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Education Policy Analysis Archives 11/23 , Arizona State University, University Of South Florida Jul 2003

Education Policy Analysis Archives 11/23 , Arizona State University, University Of South Florida

College of Education Publications

National crisis or localized problems? Getting perspective on the scope and scale of the teacher shortage / Patrick Murphy, Michael DeArmond [and] Kacey Guin.

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Developing A Sensing System For The Measurement Of Oxygen Concentration In Liquid Pb-Bi Eutectic: Quarterly Progress Report (May. 01 – July 31, 2003), Yingtao Jiang, Bingmei Fu, Woosoon Yim Jul 2003

Developing A Sensing System For The Measurement Of Oxygen Concentration In Liquid Pb-Bi Eutectic: Quarterly Progress Report (May. 01 – July 31, 2003), Yingtao Jiang, Bingmei Fu, Woosoon Yim

Transmutation Sciences Materials (TRP)

The report for Y01 has been prepared and submitted. The final part of our apparatus, the N3Si4 stirrer, was received by the end of May. The assembly of the apparatus has almost been completed. The control plan for our apparatus has been revised. To run FLUENT, a high-end Unix-based Sun workstation has been acquired. Plan has been made to ship our apparatus to LANL.

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Packet Loss Concealment In Voice Over Internet, Rishikesh S. Gokhale Jul 2003

Packet Loss Concealment In Voice Over Internet, Rishikesh S. Gokhale

USF Tampa Graduate Theses and Dissertations

Traditional telephony networks with their cumbersome and costly infrastructures are being replaced with voice being transmitted over the Internet. The Internet is a very commonly used technology that was traditionally used to transmit data. With the availability of large bandwidth and high data rates the transmission of data, voice and video over the Internet is gaining popularity. Voice is a real time application and the biggest problem it faces is the loss of packets due to network congestion. The Internet implements protocols to detect and retransmit the lost packets. However, for a real time application it is too late before …

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Levels Of Pesticide Residues In Water, Soil And Sediments From Southern Lake Victoria And Its Basin, Leonia Henry, Michale A Kishimba Jul 2003

Levels Of Pesticide Residues In Water, Soil And Sediments From Southern Lake Victoria And Its Basin, Leonia Henry, Michale A Kishimba

Tanzania Journal of Science

Water, sediment and soil samples collected from Southern Lake Victoria and its basin were analysed for 76 organochlorine, organophosphorous, carbamate and pyrethroid pesticide residues. The samples were collected from sampling stations in nine districts on the Tanzanian side of the lake, namely Mwanza, Sengerema, Geita, Ngudu, Misungwi, Magu, Bunda, Tarime and Musoma Districts. DDT and HCH residues were the only detected pesticides. The concentration of total DDT was up to 1.6 mg/L in water, 600 mg/kg dry mass in sediments and 20 mg/kg dry mass in soil. The concentration of total HCHs were up to 0.2 mg/L in water, 132 …

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Chemotaxonomic Distinction Of Selected Closely Related Acacia Species Using Chemical Properties Of Their Gum Exudates, Gs Mhinzi Jul 2003

Chemotaxonomic Distinction Of Selected Closely Related Acacia Species Using Chemical Properties Of Their Gum Exudates, Gs Mhinzi

Tanzania Journal of Science

Although Acacia senega var. senegal and Acacia senegal var. leiorhachis are regarded as being closely related botanically, their gum exudates have shown to possess different properties. The properties of the gum exudate from A. senegal var leiorhachis differ from that obtained from A. senegal var. senegal (widely accepted as the source of commercial gum arabic) by being much more viscous, less acidic and having higher proportions of insoluble gel fraction and nitrogen contents. The specific optical rotation values of the gum exudates from these two species have also been found to be different. It is proposed that some of the …

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Corrosion Inhibition Of Carbon Steel By An Amine- Fatty Acid In Acidic Solution, Joseph Buchweishaija Jul 2003

Corrosion Inhibition Of Carbon Steel By An Amine- Fatty Acid In Acidic Solution, Joseph Buchweishaija

Tanzania Journal of Science

The corrosion inhibition of carbon steel in 3% de-aerated NaCl acidic solution with amine–fatty acid corrosion inhibitor, KI384, was investigated at different temperatures using potentiodynamic polarization technique. The Corrosion rate was calculated in the presence and absence of inhibitor. The inhibition increased with an increase in inhibitor concentration and decreased with rise in temperature. The maximum percentage inhibitor efficiency was obtained at 35 oC. The percentage inhibition up to 99% was registered at a concentration of 10 ppm of KI384. The inhibitor acts as a mixed type at lower temperature and predominantly anodic at high temperature. The interrelationship between the …

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Tectonic And Sedimentary Evolution Of The Coastal Basin Of Tanzania During The Mesozoic Times, S Kapilima Jul 2003

Tectonic And Sedimentary Evolution Of The Coastal Basin Of Tanzania During The Mesozoic Times, S Kapilima

Tanzania Journal of Science

The present paper reviews and updates the stratigraphy and tectonic evolution of the coastal basin of Tanzania during the Mesozoic times based on the interpretation of existing palaeontological and stratigraphical information and supplemented by recent fieldwork investigations by the author. Tectonic events largely controlled the evolution of the coastal basin of Tanzania and the Indian Ocean. These included the Karoo rifting during Permo-Triassic, the break up of the Gondwana Supercontinent, which started with rifting in the Triassic period, the opening of the Somali basin in the Middle Jurassic, and the Cenozoic rifting along the East African rift system. The Karoo …

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Eutrophication Of Kigoma Bay Lake Tanganyika, Tanzania, Fmm Chale Jul 2003

Eutrophication Of Kigoma Bay Lake Tanganyika, Tanzania, Fmm Chale

Tanzania Journal of Science

Studies carried out in Kigoma bay (Tanzania) and at a deep water offshore station in lakeTanganyika showed marked differences in the water characteristics at the two locations. At the pelagic station, the water was more transparent (mean 11.47 m) and poor in phosphorus (mean 6.46 mg p/1 and 2.23 p/1 total and soluble reactive p, respectively). The mean transparency value for the bay was 4.05 m, and the levels of total and soluble reactive phosphorus were 14.75 mg p/1 and 4.34 mg p/1, respectively. The high water transparency coupled with low phosphorus levels in the pelagic zone indicate that the …

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Sediment Distribution And Composition On The Shallow Water Carbonate Basin Of The Zanzibar Channel, Yw Shaghude Jul 2003

Sediment Distribution And Composition On The Shallow Water Carbonate Basin Of The Zanzibar Channel, Yw Shaghude

Tanzania Journal of Science

Sediments of the shallow water carbonate basin in Zanzibar channel were investigated for composition and grain size distribution. The surface sediment composition was dominated by carbonate sands (with CaCO3 > 30%), except in the area adjacent to mainland coastline and a thin lobe which projects from Ruvu River to the middle of the channel. Mean grain size distribution closely resembles that of the carbonate content, where Tidally Dominated Reef Platform Sediments (TDRPS) located east of the Zanzibar channel were characterised by medium to coarse sands and the siliciclastic sediments adjacent to the mainland were characterised by fine sand. The TDRPS are …

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Trace Elements Characterization Of The Hydrothermally Deposited Tanzanite And Green Grossular In The Merelani – Lelatema Shear Zone, Northeastern Tanzania, Epj Malisa Jul 2003

Trace Elements Characterization Of The Hydrothermally Deposited Tanzanite And Green Grossular In The Merelani – Lelatema Shear Zone, Northeastern Tanzania, Epj Malisa

Tanzania Journal of Science

Geochemical investigations of trace element contents of different rock samples were determined in the late Proterozoic metamorphic sequences of the Mozambique Belt along the Merelani–Lelatema shear zone, northeastern Tanzania. The area is composed of the following rock types: pelitic and semi-pelitic gneisses, psammitic, hydrothermally altered including carbonate-rich, carbonate-gypsum-rich, and iron-rich rocks, pegmatite dykes and crystalline limestones. Trace element characteristics of the principal rock units in and outside the shear zone have been compiled and studied. With the exception of higher barium contents in pelites, trace element contents in the psammitic and pelitic gneisses show some similarities while in the hydrothermally …

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July 30, 2003 Cal Poly Report Digest, Public Affairs Office Jul 2003

July 30, 2003 Cal Poly Report Digest, Public Affairs Office

Cal Poly Report

No abstract provided.

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The Economics Of Managing Wildlife Disease, Richard D. Horan, Christopher A. Wolf Jul 2003

The Economics Of Managing Wildlife Disease, Richard D. Horan, Christopher A. Wolf

Michigan Bovine Tuberculosis Bibliography and Database

The spread of infectious disease among and between wild and domesticated animals has become a major problem worldwide. Upon analyzing the dynamics of wildlife growth and infection when the diseased animals cannot be identified separately from healthy wildlife prior to the kill, we find that harvest-based strategies alone have no impact on disease transmission. Other controls that directly influence disease transmission and/or mortality are required. Next, we analyze the socially optimal management of infectious wildlife. The model is applied to the problem of bovine tuberculosis among Michigan white-tailed deer, with non-selective harvests and supplemental feeding being the control variables. Using …

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Isolation And Characterization Of Thermophilic, Calcium-Precipitating Bacteria Form Calcite Deposits At Yucca Mountain, Terry Ann Else, Curtis R. Pantle, Penny S. Amy, Mark P. Buttner, Amy J. Smiecinski Jul 2003

Isolation And Characterization Of Thermophilic, Calcium-Precipitating Bacteria Form Calcite Deposits At Yucca Mountain, Terry Ann Else, Curtis R. Pantle, Penny S. Amy, Mark P. Buttner, Amy J. Smiecinski

Publications (YM)

Calcite deposits, composed of a mixture of calcium carbonate and silicon dioxide, were found in fractures and small cavities within the welded tuff of Yucca Mountain. This research investigation involves determining the presence of thermophilic, calciumprecipitating bacteria within these deposits. The possible existence of thermophilic bacteria may help to resolve the issue of whether these calcite deposits formed from precipitation of dissolved calcium carbonate in rain water transported from the overlying soil environment or as a result of upwelling of geothermally-heated waters transported from below the mountain. Evidence for microbially-influenced calcite precipitation in these deposits is indicated by the presence …

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Campus Observer, Volume 4, Issue 12, Office Of University Communications, Florida Institute Of Technology Jul 2003

Campus Observer, Volume 4, Issue 12, Office Of University Communications, Florida Institute Of Technology

Campus Observer

The Campus Observer was a newsletter for the Florida Tech community produced by the Office of University Communications (now the Office of Marketing and Communications). Visit the Campus Observer Collection Guide for more information. Earlier publications of this kind include Tech Talk and Technology Topics.

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A Multicentered Approach To Integrated Qm/Qm Calculations. Applications To Multiply Hydrogen Bonded Systems, Brian W. Hopkins, Gregory S. Tschumper Jul 2003

A Multicentered Approach To Integrated Qm/Qm Calculations. Applications To Multiply Hydrogen Bonded Systems, Brian W. Hopkins, Gregory S. Tschumper

Chemistry Faculty Research & Creative Works

A multicentered integrated QM/QM technique has been developed. By separating high-level calculations in distinct regions of molecules, the multicentered approach supplants a single large high-level calculation with several smaller calculations. Due to the step polynomial scaling of traditional ab initio quantum chemical methods, this separation significantly enhances the computational efficiency of QM/QM methods. The straightforward implementation of this multicentered approach is illustrated with several large poly-alcohols that form hydrogen bonds with water. The largest alcohol-water complex contains 81 atoms. For properly selected model systems, this multicentered approach introduces essentially no error in the dissociation energies of these complexes relative to …

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