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101.
Peter J. McAlindon 《Computers & Industrial Engineering》1992,23(1-4):205-207
Enhancing the way people use computers to perform tasks has become a very important issue in interface design and human-computer interactions. When the concept of human-computer interaction first began to emerge it was commonly understood as the hardware and software through which a human and computer could effectively communicate (Laurel, 1990). This effective communication is also know as user-friendliness. The concept of user friendliness has recently been expanded to include various attributes and cognitive aspects of the user's needs and experiences. Focus should be on the user's experiences, expectations, preferences, and cognitive aspects in developing efficient and effective computer interface designs. It is the basic premise of this paper to emphasize using a user-centered design in developing computer interfaces. 相似文献
102.
When using a conventional demodulator, a sufficient condition to maintain ODS-CDMA codeword orthogonality is constant relative channel amplitude over the codeword duration. When transmitted over a memoryless, AM/PM nonlinearity channel, the chip-to-chip fluctuating amplitude of a composite ODS-CDMA QPSK waveform produces a chip-to-chip fluctuating phase that deorthogonalizes the ODS-CDMA codewords, resulting in an additional multiple access self-interference similar to that found in asynchronous DS-CDMA. For ODS-CDMA QPSK in an AM/PM nonlinearity channel, we utilize the Central Limit Theorem, derive, and evaluate: (i) an expression for the signal-to-distortion ratio at the demodulator output, (ii) an expression for the uncoded bit error probability, and (iii) an upper bound on the convolutionally-coded bit error probability. We find that the degradation to BER depends on both the AM/PM nonlinearity slope and the ODS-CDMA channel loading. 相似文献
103.
John K. Montgomery Peter L. Drzal Kenneth R. Shull K. T. Faber 《Journal of the American Ceramic Society》2002,85(5):1164-1168
A new ceramic processing method, thermoreversible gelcasting (TRG), has been developed. The method uses a gelation process that can be reversed multiple times. Two Al2 O3 systems have been explored with the use of a specific triblock copolymer to form a binding gel network. The mixture becomes a free-flowing liquid on heating above 60°C. However, on cooling below 60°C, the slurry instantaneously transforms to a physical gel. This process can be reversed easily (essentially with an infinite processing time window) while the solvent is present in the system, which is advantageous when trying to produce high-quality dense pieces if initial casting irregularities occur. Near-theoretically dense specimens have been produced with properties consistent with reported values of high-density Al2 O3 . 相似文献
104.
105.
Kinicki Angelo J.; Hom Peter W.; Trost Melanie R.; Wade Kim J. 《Canadian Metallurgical Quarterly》1995,80(3):354
Two studies examined whether the accessibility of performance prototypes influences performance appraisals. Pilot studies revealed students used performance prototypes when rating instructor performance. Study 1 manipulated the accessibility of these prototypes and the time delay of performance ratings. Results showed no effect of the prime on rating error and accuracy; however, discrimination accuracy decreased over time and recognition bias became more conservative. Study 2 manipulated prototype accessibility and type of rating stimuli (videotape vs. vignette). Rating accuracy and recall were higher for vignette than videotape stimuli, and only those participants exposed to the vignette exhibited priming effects. Results supported transfer-appropriate processing and implied that cognitive primes may have a stronger effect on performance ratings based on "paper-people" than videotaped stimuli. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
106.
Dusts,scale, slags,sludges... Not wastes,but sources of profits 总被引:3,自引:0,他引:3
Peter J. Koros 《Metallurgical and Materials Transactions B》2003,34(6):769-779
Historically, the steel industry has focused on the need for and the many benefits of recycling steel that is discarded either
in its own or in its customers’ manufacturing processes, as well as in recovery and reuse of steel scrap that arises after
the product has served its intended purpose. In fact, modern steelmaking relies on the use of recycled iron units for at least
half of its production.
The other side of the story is the fate of the non-steel by-products (e.g., oxide dusts, sludges, scales, slags, spent refractories and the contained “low grade” energy units that are generated as
natural adjuncts to iron and steelmaking processes). These valuable by-products often are classified as “wastes” and are discarded
to landfills, at significant cost, although in reality they offer significant potential for cost savings or profit if reintroduced
into the industrial arena via well planned programs. Examples of such instances will be presented, including energy credit issues, in the hope of pointing
the way for future expansion of benefits from these opportunities.
Preparing for a challenge and honor such as the Howe Memorial Lecture, one has to stand in awe of the accomplishments of the
predecessor we honor in this forum. He worked in the early days of our industry without the benefits of the many technological
improvements he and his successors brought to play as the years went by. John Stubbles, in his Howe Memorial Lecture in 1997,[1] presented a masterful and entertaining biography of Howe and his very active and prolific life. Perhaps the most telling
quotation he attributed to Howe is very pertinent to the topic we will address presently: “Metallurgy lives by profit, not
logic,” to which I would like to add a comment that bears on the topic of this lecture from the 1991 Howe lecturer, my friend
and mentor Bill Dennis, “Where there is muck, there is money.”
There are numerous examples of “one hand washes the other” in this business; that is, of the synergism between needs and capabilities.
We will address some of these situations, such as in a new process under development for dezincing of post consumer scrap,
and in the use of iron units in by-product oxides and recycling of ladle slags and of spent refractories.
Peter J. Koros, the Iron and Steel Society’s 77th Howe Memorial Lecturer (2001), is Principal of Koros Associates, Inc. (Pittsburgh,
PA), a consultancy he founded following retirement from the former LTV Steel Company where he worked for nearly 41 years,
retiring as Senior Research Consultant. He earned the Bachelor of Science degree in Metallurgical Engineering from Drexel
University, and his master’s and doctoral degrees in Metallurgy from the Massachusetts Institute of Technology (MIT). In 1958,
he joined Jones and Laughlin Steel (which became LTV Steel Company), where he held positions in research (Director, Process
Metallurgy), Technical Services and Quality Control, with most activities focused on steelmaking and related areas.
He was responsible for J&L’s development work in injection technology for desulfurization of hot metal and steel, was the
inventor of the patented co-injection concept now in use worldwide, and had the lead role in LTV Steel’s programs for degalvanizing
scrap and for recovery and utilization of by-product oxides. He led the AISI Opt-In program for degalvanizing scrap and the
LTV-USS pilot program for processing “by-product” oxides. Koros has authored more than 75 publications and presentations,
and holds eight U.S. patents, the latest issued in 2000.
Dr. Koros was elected a Distinguished Member and Fellow of the ISS in 1984 and a Fellow of ASM International in 1988. Other
honors include the ISS Distinguished Service Award (1998), ISS Electric Furnace Honorable Mention Citation (1987), International
Magnesium Association Design and Applications Award (1978), AISI Gold (1977) and Silver (1969) Medals, ISS Herty (1963), McKune
(1963), and Toy (1962) Awards.
Koros served on the Technical Advisory Committee of the AISI-DOE Direct Steelmaking Program and its follow-on Waste Oxide
Recycling Program. He was chairman of the AISI Task Force on Degalvanizing Steel Scrap and of the Industrial Advisory Panel
to the Argonne Lab-MRI Program on Dezincing Steel Scrap. The 2001 Howe Memorial Lecture, titled “Dusts, Scale, Slags, Sludges
... Not Wastes But Sources of Profits,” as well as an invited Keynote Lecture for an International Recycling Conference in
Sweden (June 2002, “Iron Units in Search of a Home: New Steel”) were based on the experience from these programs.
Koros has been an active member of the ISS Advanced Technology Committee for which he participated in and chaired several
symposia, including New Melting Technologies II (October 2002) and the first New Melting Technologies Symposium (1997). He
was Director of the ISS 2000 Short Course on Injection Technology, a lecturer in the 2000 ISS/AISI Course on BOF Steelmaking,
lead Co-chairman for the Elliott Symposium (1990), and Chairman of the Program Committee for the Fifth International Iron
and Steel Congress (1986). Dr. Koros served on the Industrial Advisory Board of MIT’s Materials Processing Center (1995–98)
and the AISI’s Iron and Steel Research Subcommittee (1976–86.) He was chairman of the ISS National Science Foundation Advisory
Committee, the Advisory Council of the U.S. Bureau of Mines Generic Minerals Technology Center for Pyrometallurgy Research
(1983–85), and of the Advisory Board for Carnegie Mellon University’s Center for Iron and Steel Research, for which he served
as chairman (1991–1992). Service included participation in the NRC-NAS Alternative Energy and Development Strategy Study (1989–90.)
Koros was very active in the creation of the ISS, having served as Chairman of the predecessor TMS Iron and Steel Division
in 1972–73 and on the AIME Board of Directors (1974).
Professional Society memberships: ISS (elected Distinguished Member and Fellow, Life Member), TMS (Senior or Life Member),
ASM International (elected Fellow, Life Member), and AISE. 相似文献
107.
Peter Speier 《Journal of Electronic Materials》1991,20(12):993-999
The technological limits for ultra high speed devices are now rapidly expanding due to the use of quantum well (QW) materials.
This new class of materials gives the opportunity of tailoring materials parameters by controlling geometries on an atomic
scale. They look very promising as materials for lasers, detectors and transistors suitable even above 10 Gb/s. It will be
demonstrated that state of the art MQW structures can be realized in both material systems, InGaAsP/InP and InGaAlAs/InP.
Parallel lateral laser structures (e.g. SIBH, BRS and TBH) have been designed to take full benefit of QW technology. Ultimate reduction of parasitics, whilst using
potential low cost fabrication technologies is the basis for achieving high bitrate (10 Gb/s) MQW lasers, even with the stronger
damping in QW material. Using the DFB-SIBH laser structure 10 Gb/s large signal experiments are successfully performed with
bulk, MQW and SLMQW lasers. Extremely low fall times of 44 ps are achieved. Additional MQW based improvements are observed
such as: −3 times higher differential gain, increased output power (>110 mW), 2.5 times lower chirp (Δλ−20dB = 0.40 nm at 10 Gb/s modulation), and 2 dB gain in power budget at 10 Gb/s digital transmission. 相似文献
108.
This article describes the development and validation of scales to measure clients' outcome optimism, perceived progress, and self-agency related to change in problems presented in therapy. In Study 1, initial confirmatory and subsequent exploratory factor analyses (N?=?257) identified effort and persistence as an additional unique factor and guided selection of items to measure the 4 constructs. In Study 2, confirmatory factor analysis of the revised scales with a new sample (N?=?93) confirmed the measurement model. Results of convergent and discriminant validity analyses generally were in the predicted directions. The Perceived Progress scale demonstrated criterion validity with changes in dyadic adjustment and family functioning. The Outcome Optimism and Self-Agency scales showed variability in their relationship to the Perceived Progress scale over the first 3 sessions of therapy. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
109.
110.
Peter Brandt 《Journal für Verbraucherschutz und Lebensmittelsicherheit》2007,1(9):393-398
Um Auskunft über die wirtschaftliche Bedeutung von Kaffee, Tee und Kakao zu geben, werden in diesem Mini-Review u.a. aktuelle
Angaben zur weltweiten Produktion dieser drei „Exoten“ gemacht (Menge und Herkunftsl?nder), die jeweiligen Import-Anteile
der Produktionsl?nder nach Deutschland (bzw. in die EU) benannt, der Pro-Kopf-Verbrauch an Kaffee, Tee oder Kakao in Deutschland
mit dem anderer Staaten verglichen und – sofern m?glich – Einblick gegeben in die Entwicklung von weltweitem Angebot und Nachfrage
und die damit verbundene Preisentwicklung in den vergangenen Jahren. 相似文献