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81.
Gary Demos 《The Visual computer》2005,21(12):961-978
Gary Demos discovered computer graphics while hearing a computer-generated film presentation at CalTech in 1970 by John Whitney
Sr. Gary then began working under the direction of Ivan Sutherland in Utah to develop early computer graphics hardware and
software. In 1974 Gary and John Whitney Jr. started the “Motion Picture Project” at Information International to produce computer
generated simulated scenes for movies (Futureworld, Looker, and Tron) and commercials. These early computer-generated visuals
were quite challenging given the level of software and hardware technology available in the 1970’s. In 1981 Gary and John
left Information International to form Digital Productions, where they produced effects for the movies Last Starfighter and
“2010”, which were both released in 1984. Digital Productions used the Cray XMP computer, together with the Digital Film Printer
that they had developed at Information International. Following a hostile takeover by Omibus of Digital Productions in 1986,
Whitney/Demos Productions was formed, using a Thinking Machine parallel computer. This paper describes the technical challenges
and achievements of this early visual computing. 相似文献
82.
Genetic subsets regression 总被引:1,自引:0,他引:1
Agus Sudjianto Gary S. Wasserman Hinurimawan Sudarbo 《Computers & Industrial Engineering》1996,30(4):839-849
Subset regression procedures have been shown to provide better overall performance than stepwise regression procedures. However, due to the combinatorial nature of evaluating each potential subset, subset regression techniques are costly to use. To resolve this difficulty, the use of a simple genetic algorithm (GA) is proposed to reduce the number of subsets which must be evaluated. Any of a number of popular criteria, including Mallows' Cp, MSE, R2, AIC, etc., can be used to drive the search strategy associated with the use of the GA. Several illustrated examples on its use are provided. 相似文献
83.
Kate Sanders Sally Fincher Dennis Bouvier Gary Lewandowski Briana Morrison Laurie Murphy Marian Petre Brad Richards Josh Tenenberg Lynda Thomas Richard Anderson Ruth Anderson Sue Fitzgerald Alicia Gutschow Susan Haller Raymond Lister Renée McCauley John McTaggart Christine Prasad Terry Scott Dermot Shinners-Kennedy Suzanne Westbrook Carol Zander 《Expert Systems》2005,22(3):121-128
Abstract: This paper presents a case study of the use of a repeated single‐criterion card sort with an unusually large, diverse participant group. The study, whose goal was to elicit novice programmers' knowledge of programming concepts, involved over 20 researchers from four continents and 276 participants drawn from 20 different institutions. In this paper we present the design of the study and the unexpected result that there were few discernible systematic differences in the population. The study was one of the activities of the National Science Foundation funded Bootstrapping Research in Computer Science Education project (2003). 相似文献
84.
Gary T. Anderson Youlong Yang Gang Cheng 《Journal of Intelligent and Robotic Systems》2009,54(5):755-767
This paper proposes a unique oscillator-based robot controller with learning abilities to effectively guide a team of robots
operating in uncertain environments. To verify this, we designed four separate controllers and compared their performance
in a series of tests in several different environments. The experiments used a team of three robots to explore arenas with
variable lighting and different obstacle patterns, with a goal of having the team as a whole absorb as much light as possible.
The four controllers were: a reactive controller, an oscillator with fixed parameters, an oscillator whose parameters changed
based on the pattern of sensor information received, and an oscillator-based controller that used reinforcement learning.
Experiments confirmed that the proposed method outperforms the others in all environments tested.
This material is based upon work supported in part by the U.S. Army Research Office under grant/contract number DAAG55-98-1-0011. 相似文献
85.
Gary Cokins 《EDPACS》2013,47(6):11-21
Abstract Enterprise performance management (EPM) is the integration of control and improvement methods imbedded with analytics. Its methods include the strategy map, balanced scorecards, costing (including activity based cost management), budgeting, forecasting and resource capacity requirements planning. These methods fuel other core solutions such as customer relationship management (CRM), supply chain management (SCM), risk management, and human capital management systems, as well as lean management and Six Sigma initiatives. 相似文献
86.
The objective of the current investigation is to characterize the dynamic strain aging (DSA) behavior in alloys 800H and 690. Constant extension rate tests were conducted at strain rates in the range of 10?4 s?1 to 10?7?s?1and temperatures between 295?K and 673?K (22?°C and 400?°C), in an argon atmosphere. Maps for the occurrence of serrated flow as a function of strain rate and temperature were built for both alloys. The enthalpy of serrated flow appearance of alloy 800H was found to be 1.07?±?0.30?eV. 相似文献
87.
A method of loading a set of tools to the different machining centres of a shop is presented, where each part visits only one of the machining centres for its entire processing. Any tools which are required but unavailable for the processing of a part are borrowed from other machining centres. As a real-time control, the tool-returning policies for those borrowed tools and the job-dispatching rules at the machining centres are evaluated to maximize the throughput performance of the shop. Some experimental results are provided. 相似文献
88.
Kate J. Norris Andrew J. Lohn Takehiro Onishi Elane Coleman Vernon Wong Ali Shakouri Gary S. Tompa Nobuhiko P. Kobayashi 《Journal of Electronic Materials》2012,41(5):971-976
We report the growth of erbium monoantimonide (ErSb) thin films on indium antimonide (100) substrates by low-pressure metalorganic
chemical vapor deposition. The growth rate of ErSb thin films shows strong dependency on the growth temperature and the Sb/Er
precursor molar flow rate ratio. Scanning electron microscopy, energy-dispersive x-ray spectroscopy, and x-ray diffractometry
(XRD) were employed to study the ErSb thin films grown under the growth conditions that gave the maximum growth rate in the
range we investigated. We also report the growth of two types of nanocomposites in which ErSb nanocolumns or nanoslabs with
lengths ~500 nm and diameters 20 nm to 30 nm are embedded in Zn-doped InGaSb (ErSb/InGaSb:Zn) and ErSb nanoparticles with
diameters of ~30 nm are embedded in Zn-doped InSbAs (ErSb/InSbAs:Zn). These nanocomposites were intended to increase phonon
scattering in a mid-to-long phonon wavelength range to reduce lattice thermal conductivity. We used time-domain thermoreflectance
to measure total thermal conductivity for the two types of nanocomposites, obtaining 4.0 ± 0.6 W/mK and 6.7 ± 0.8 W/mK for
the ErSb/InAsSb:Zn and ErSb/InGaSb:Zn nanocomposites, respectively, which suggests that the thermal conductivity was close
to or slightly smaller than the alloy limit of the two ternary alloy hosts. The two nanocomposites were further studied by
transmission electron microscopy (TEM) to reveal their microscopic features and by XRD to assess their crystalline structures. 相似文献
89.
The method of the calculus of variations and the maximum principle are preposed for the design of 'LQR' controllers with the worst case disturbance rejection for a linear time-varying (LTV) plant on finite horizon. The disturbance is bounded by either the windowed L 相似文献
90.
Madhav P. Yadav Gary D. StrahanSudarsan Mukhopadhyay Arland T. HotchkissKevin B. Hicks 《Food Hydrocolloids》2012,26(2):326-333
Corn fiber arabinoxylan is hemicellulose B isolated from the fibrous portions (pericarp, tip cap, and endosperm cell wall fractions) of corn kernels and is commonly referred to as corn fiber gum (CFG). Our previous studies showed that CFG isolated from corn bran (a byproduct of corn dry milling) contains very little protein and is an inferior emulsifier for oil-in-water emulsion systems as compared to corn fiber gum isolated from corn fiber derived from the corn wet-milling process. The protein deficient CFG isolated from corn bran was covalently conjugated with byproducts of cheese processing, β-lactoglobulin (β-LG) and whey protein isolate (WPI) using an economical food-grade Maillard-type heating reaction for the purpose of increasing their commercialization potential as a food emulsifier and soluble nutritional additive in beverages. The formation of the CFG-protein conjugates has been confirmed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). It has also been demonstrated that CFG-protein conjugates are capable of producing fine emulsions with better stability than either CFG or protein alone. The molecular characterization of CFG-protein conjugates was performed by high-performance size-exclusion chromatography (HPSEC) coupled to on-line multi-angle laser light scattering and viscometric detection. The analysis by HPSEC revealed that CFG-protein conjugates had higher weight-average molar mass (Mw, 340-359 kDa) and polydispersity (Mw/Mn, 1.74) than the corresponding unconjugated CFG (Mw, 290 kDa and Mw/Mn, 1.35). The z-average root-mean-square radius of gyration (Rgz) of CFG-protein conjugates was slightly higher (30.5-33.5 nm) in comparison to CFG (29.5 nm) but their weight-average-intrinsic viscosity (η) remained unchanged (about 1.32 dL g−1). The Mark-Houwink exponent “a” of conjugates (0.40) was lower than the unconjugated CFG (0.53) indicating the formation of a more compact structure after conjugation with protein. These findings should benefit the beverage industry, which can use this information to produce a high quality emulsifier from the low-value byproducts of corn dry milling and cheese processing. 相似文献