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71.
Jason Heikenfeld Paul Drzaic Jong‐Souk Yeo Tim Koch 《Journal of the Society for Information Display》2011,19(2):129-156
Abstract— The commercial success of monochrome electronic paper (e‐Paper) is now propelling the development of next‐generation flexible, video, and color e‐Paper products. Unlike the early battles in the 1980s and 1990s between transmissive and emissive display technologies, there is a extraordinary diversity of technologies vying to become the next generation of e‐Paper. A critical review of all major e‐Paper technologies, including a technical breakdown of the performance limitations based on device physics and commentary on possible future breakthroughs, is presented. In addition, the visual requirements for color e‐Paper are provided and compared to standards used in conventional print. It is concluded that researchers have much work remaining in order to bridge the significant gap between reflective electronic displays and print‐on‐paper. 相似文献
72.
Experimental test of a robust formation controller for marine unmanned surface vessels 总被引:1,自引:0,他引:1
Daniel Schoerling Chris Van Kleeck Farbod Fahimi Charles Robert Koch Alfons Ams Peter Löber 《Autonomous Robots》2010,28(2):213-230
Experiments with two formation controllers for marine unmanned surface vessels are reported. The formation controllers are
designed using the nonlinear robust model-based sliding mode approach. The marine vehicles can operate in arbitrary formation
configurations by using two leader-follower control schemes. For the design of these controller schemes 3 degrees of freedom
(DOFs) of surge, sway, and yaw are assumed in the planar motion of the marine surface vessels. Each vessel only has two actuators;
therefore, the vessels are underactuated and the lack of a kinematic constraint puts them into the holonomic system category.
In this work, the position of a control point on the vessel is controlled, and the orientation dynamics is not directly controlled.
Therefore, there is a potential for an oscillatory yaw motion to occur. It is shown that the orientation dynamics, as the
internal dynamics of this underactuated system, is stable, i.e., the follower vehicle does not oscillate about its control
point during the formation maneuvers. The proposed formation controller relies only on the state information obtained from
the immediate neighbors of the vessel and the vessel itself. The effectiveness and robustness of formation control laws in
the presence of parameter uncertainty and environmental disturbances are demonstrated by using both simulations and field
experiments. The experiments were performed in a natural environment on a lake using a small test boat, and show robust performance
to parameter uncertainty and disturbance. This paper reports the first experimental verification of the above mentioned approach,
whose unique features are the use of a control point, the zero-dynamic stability analysis, the use of leader-follower method
and a nonlinear robust control approach. 相似文献
73.
Claire M. Côte Chris J. Moran Christopher J. Hedemann Christian Koch 《Environmental Modelling & Software》2010,25(12):1664-1671
Concerns about the difficulties in securing water have led the Australian coal mining industry to seek innovative ways to improve its water management and to adopt novel strategies that will lead to less water being used and more water being reused. Simulation tools are essential to assess current water management performance and to predict the efficiency of potential strategies. As water systems on coal mines are complex and consist of various inter-connected elements, a systems approach was selected, which views mine site water management as a system that obtains water from various sources (surface, groundwater), provides sufficient water of suitable quality to the mining tasks (coal beneficiation, dust suppression, underground operations) and maintains environmental performance. In this paper, the model is described and its calibration is illustrated. The results of applying the model for the comparison of the water balances of 7 coal mines in the northern Bowen Basin (Queensland, Australia) are presented. The model is used to assess the impact of applying specific water management strategies. Results show that a simple systems model is an appropriate tool for assessing site performance, for providing guidance to improve performance through strategic planning, and for guiding adoption of site objectives. 相似文献
74.
Charles A. Pittinger Jere S. Sellers Daniel C. Janzen Dianne G. Koch T. Michael Rothgeb Michael L. Hunnicutt 《Journal of the American Oil Chemists' Society》1993,70(1):1-15
Life-cycle inventories were compiled to characterize natural resource requirements and environmental emissions associated
with the sourcing and production of selected, detergent-grade surfactants and surfactant feedstocks. Petrochemical surfactant
types examined were linear alkylbenzene sulfonate, alcohol sulfate (AS), alcohol ethoxylate (AE) and alcohol ethoxylate sulfate
(AES). Oleochemical surfactants derived from palm oil, palm kernel oil and inedible tallow were AS, AE, AES and (for palm
oil and tallow) methyl ester sulfonate. It was determined that natural resource requirements were primarily related to the
source of feedstock and secondarily to surfactant type. Likewise, the composition and mass of atmospheric, aqueous and solid
emissions were principally determined by feedstock source. Energy requirements varied as a function of both feedstock and
surfactant type. The inventories do not support fundamental shifts in surfactant usage or feedstock sourcing on the basis
of environmental concerns, as no single surfactant or feedstock was identified as superior across all resource and emissions
criteria examined. The data provide baselines for evaluating opportunities for resource optimization, pollution prevention
and waste minimization within each production technology surveyed. 相似文献
75.
CD Koch 《Canadian Metallurgical Quarterly》1976,14(7):373-374
Results obtained with the commercial test-set "GOD-UV" (Dr. Haury, München) are reported. This method permits the determination of serum-glucose within 3 minutes. The procedure is satisfactory in normal and hyperglycaemic patients. In the hypoglycaemic state, however, there is a danger of misinterpretation. The glucose oxidase-UV is compared with the hexokinase reaction. 相似文献
76.
H Villalobos ES Canales A Zárate J Soria C MacGregor 《Canadian Metallurgical Quarterly》1976,83(2):236-242
Serum levels of prolactin (PRL), FSH, LH and oestradiol-17 beta were determined by radioimmunoassay in 57 lactating women and in 20 women in whom lactation was inhibited by ergocryptine (CS-154). Women who breast fed their infants exhibited high PRL levels which abruptly declined within 48 h post-partum, and remained low for the duration of the study. Serum FSH was undetectable during the first week post-partum in lactating as well as in CB-154 treated women. Thereafter, lactating women showed increasing FSH levels which reached a maximum by the third week post-partum. These FSH values were higher in lactating women than in the CBS-154 treated group. In contrast, LH levels were higher in those women receiving CB-154. Serum oestradiol-17 beta remained in low levels throughout the study, and no difference was observed between the two groups of subjects. From these results it seems that: 1) inhibition of PRL secretion leads to a faster recovery of gonadotrophin secretion toward the "menstrual type", and 2) PRL suppression produces no effect on the ovarian oestrogen production. 相似文献
77.
Wall Jacqueline Remondet; Busch Monique; Koch Steven M.; Alexander Gina; Minnich Heike; Jackson-Walker Susan 《Canadian Metallurgical Quarterly》2005,2(1):39
Questions are often raised regarding the effectiveness and value of treatment programs for children and families. Recently, programs have been increasingly held accountable for services offered. In response, the member agencies of IARCCA have developed a comprehensive outcome measurement program. This article describes the project, focusing on the conditions that led to its inception and how the measurement plan was developed. In addition, the article includes information on the selection of personnel, measurement instruments, and methods and on the process of data collection. Summary results are provided, including how these results are utilized to improve services. Finally, the continued expansion and future directions of the Outcome Project are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
78.
Lippert M. Becker-Pecbau P. Breitling H. Koch J. Kornstadt A. Roock S. Schmolitzky A. Wolf H. Zullighoven H. 《Computer》2003,36(6):67-73
Using methodological extensions to adapt extreme programming (XP) for major projects offers a high security and reliability without limiting software development's advantages. The authors describe their use of XP extensions that focus on development's planning and controlling aspects, demonstrating that a suitably adapted agile development process is applicable to long-term, large-system projects. 相似文献
79.
Chow W.W. Knorr A. Hughes S. Girndt A. Koch S.W. 《IEEE journal of selected topics in quantum electronics》1997,3(2):136-141
This paper describes the results of a microscopic treatment of carrier-carrier scattering effects in the optical gain and refractive index spectra of a quantum-well semiconductor laser structure. The approach uses the Semiconductor Maxwell Bloch equations to describe the interaction between the carriers and the laser field, in the presence of many-body Coulomb interactions. Coulomb correlation effects are treated at the level of quantum kinetic theory in the Markovian limit. This approach shows the presence of nondiagonal Coulomb correlation contributions, in addition to the familiar diagonal contributions giving rise to polarization dephasing 相似文献
80.
Design for six sigma through robust optimization 总被引:5,自引:1,他引:5
The current push in industry is focused on ensuring not only that a product performs as desired but also that the product consistently performs as desired. To ensure consistency in product performance, “quality” is measured, improved, and controlled. Most quality initiatives have originated and been implemented in the product manufacturing stages. More recently, however, it has been observed that much of a product’s performance and quality is determined by early design decisions, by the design choices made early in the product design cycle. Consequently, quality pushes have made their way into the design cycle, and “design for quality” is the primary objective. How is this objective measured and met? The most recent quality philosophy, also originating in a manufacturing setting, is six sigma. The concepts of six sigma quality can be defined in an engineering design context through relation to the concepts of design reliability and robustness – probabilistic design approaches. Within this context, design quality is measured with respect to probability of constraint satisfaction and sensitivity of performance objectives, both of which can be related to a design “sigma level”. In this paper, we define six sigma in an engineering design context and present an implementation of design for six sigma – a robust optimization formulation that incorporates approaches from structural reliability and robust design with the concepts and philosophy of six sigma. This formulation is demonstrated using a complex automotive application: vehicle side impact crash simulation. Results presented illustrate the tradeoff between performance and quality when optimizing for six sigma reliability and robustness. 相似文献