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11.
The problem of on‐line estimation of the conversion and composition evolutions in a pressurized batch copolymer reactor with temperature and pressure measurements was addressed. The estimation model consisted of mass and energy balances with a pressure equation built from phase‐equilibrium considerations. The application of a nonlinear geometric estimation approach yielded the underlying solvability condition with physical meaning, a straightforward estimator construction, and a conventional‐like tuning procedure. The resulting barocalorimetric estimator was an on‐line dynamic measurement processor with a model‐based predictor and a measurement‐driven corrector, and whose implementation did not require the polymerization rates and heat‐transfer coefficient function dependencies. The technique was tested with a representative laboratory styrene–butadiene system. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 475–482, 2005 相似文献
12.
Claudia Kuenzer Patrick Leinenkugel Matthias Vollmuth Stefan Dech 《International journal of remote sensing》2014,35(8):2752-2779
In this article we present the results of a comparison of six globally available land-cover products for the Mekong Basin – an area that spans 795,000 km2 and comprises parts of six riparian countries: China, Myanmar, Thailand, Laos, Cambodia, and Vietnam. The basin covers most climatic zones: from high-altitude, snow-covered mountainous regions in the north, to subtropical and tropical rainforest areas and agricultural land further south. The geopolitically important region not only is home to over 72,000,000 inhabitants, but also is a centre of attention of several environmental modelling experts, trying to assess future hydrologic dynamics, climate variability, as well probable land-use developments in the area.We compare land-cover products of the University of Maryland, UMD 1992–1993, the GLC 2000 product, the GlobCover products of 2004–2006 and 2009, as well as the MODIS-derived land-cover products of 2001 and 2009. For harmonization of individual legends, the Land Cover Classification System, LCCS, has been employed. However, even after harmonization, cross-tabulation among the products reveals extreme differences, where the impact of differing classification algorithms weighs higher than the impact of temporal coincidence of products. Especially, differences within mixed-vegetation classes are large, strongly impacting the overall assessment of forested land, other vegetated land, and even cultivated land in the Mekong Basin. The findings presented here are of high relevance for the modelling community as well as Mekong-related environmental studies, which should consider global remote-sensing-derived products with caution and solid background knowledge. 相似文献
13.
Claudia Kuster Jean‐Charles Bazin Cengiz Öztireli Teng Deng Tobias Martin Tiberiu Popa Markus Gross 《Computer Graphics Forum》2014,33(2):1-10
Multi‐view reconstruction aims at computing the geometry of a scene observed by a set of cameras. Accurate 3D reconstruction of dynamic scenes is a key component for a large variety of applications, ranging from special effects to telepresence and medical imaging. In this paper we propose a method based on Moving Least Squares surfaces which robustly and efficiently reconstructs dynamic scenes captured by a calibrated set of hybrid color+depth cameras. Our reconstruction provides spatio‐temporal consistency and seamlessly fuses color and geometric information. We illustrate our approach on a variety of real sequences and demonstrate that it favorably compares to state‐of‐the‐art methods. 相似文献
14.
This study uses a hostage negotiation setting to demonstrate how a team of strategic police officers can utilize specific coping strategies to minimize uncertainty at different stages of their decision-making in order to foster resilient decision-making to effectively manage a high-risk critical incident. The presented model extends the existing research on coping with uncertainty by (1) applying the RAWFS heuristic (Lipshitz and Strauss in Organ Behav Human Decis Process 69:149–163, 1997) of individual decision-making under uncertainty to a team critical incident decision-making domain; (2) testing the use of various coping strategies during “in situ” team decision-making by using a live simulated hostage negotiation exercise; and (3) including an additional coping strategy (“reflection-in-action”; Schön in The reflective practitioner: how professionals think in action. Temple Smith, London, 1983) that aids naturalistic team decision-making. The data for this study were derived from a videoed strategic command meeting held within a simulated live hostage training event; these video data were coded along three themes: (1) decision phase; (2) uncertainty management strategy; and (3) decision implemented or omitted. Results illustrate that, when assessing dynamic and high-risk situations, teams of police officers cope with uncertainty by relying on “reduction” strategies to seek additional information and iteratively update these assessments using “reflection-in-action” (Schön 1983) based on previous experience. They subsequently progress to a plan formulation phase and use “assumption-based reasoning” techniques in order to mentally simulate their intended courses of action (Klein et al. 2007), and identify a preferred formulated strategy through “weighing the pros and cons” of each option. In the unlikely event that uncertainty persists to the plan execution phase, it is managed by “reduction” in the form of relying on plans and standard operating procedures or by “forestalling” and intentionally deferring the decision while contingency planning for worst-case scenarios. 相似文献
15.
Josianne Lefebvre Federico Galli Claudia L. Bianchi Gregory S. Patience Daria C. Boffito 《加拿大化工杂志》2019,97(10):2588-2593
X‐ray photoelectron spectroscopy (XPS) is a quantitative surface analysis technique used to identify the elemental composition, empirical formula, chemical state, and electronic state of an element. The kinetic energy of the electrons escaping from the material surface irradiated by an x‐ray beam produces a spectrum. XPS identifies chemical species and quantifies their content and the interactions between surface species. It is minimally destructive and is sensitive to a depth between 1–10nm. The elemental sensitivity is in the order of 0.1 atomic %. It requires ultra high vacuum ( Pa) in the analysis chamber and measurement time varies from minutes to hours per sample depending on the analyte. XPS dates back 50 years ago. New spectrometers, detectors, and variable size photon beams, reduce analysis time and increase spatial resolution. An XPS bibliometric map of the 10 000 articles indexed by Web of Science[1] identifies five research clusters: (i) nanoparticles, thin films, and surfaces; (ii) catalysis, oxidation, reduction, stability, and oxides; (iii) nanocomposites, graphene, graphite, and electro‐chemistry; (iv) photocatalysis, water, visible light, and ; and (v) adsorption, aqueous solutions, and waste water. 相似文献
16.
Definition of the problem
In Germany as well as in many other countries, mentally ill criminals who are not guilty by reasons of insanity can be sentenced to psychiatric treatment in forensic clinics. In 2011, the German Constitutional Court substantially strengthened these patients’ right to self-determination in case of treatment refusal.Arguments
In this context, we discuss the significance of instruments of advance healthcare planning. First, we describe the context of psychiatric treatment in forensic clinics and the changes the new German legal regulations brought about. A case study helps to illustrate the consequences of treatment refusal for both patient and healthcare personnel.Conclusion
Eventually, we discuss if and how advance directives and joint crisis plans can be useful in forensic clinics and how additional measures can help to facilitate patient self-determination.17.
Claudia Li Jian Song Shude Zhang Xiaoyao Tan Xiuxia Meng Jaka Sunarso Shaomin Liu 《Journal of the American Ceramic Society》2021,104(5):2268-2284
New CO2-resistant dual-phase Sm0.2Ce0.8O1.925–SrCo0.4Fe0.55Zr0.05O3-δ (SDC-SCFZ) ceramics present a promising outlook for potential future applications in membrane reactors and solid oxide fuel cells. Their high oxygen permeation flux and stability in CO2 sweep gas also allow their integration in oxyfuel combustion. Here the structural characteristics, electrical conductivities, thermal expansion behaviors, and oxygen permeabilities of four different SDC-SCFZ membranes with weight ratios of 10:90, 25:75, 50:50, and 75:25 (SDC:SCFZ) are systematically studied. Among these four SDC-SCFZ compositions, 0.6 mm-thick 25 wt% SDC-75 wt% SCFZ displayed the highest oxygen permeation fluxes that reach 1.26 mL min−1 cm−2 at 950°C and retained its phase integrity under alternating He and CO2 sweep gas over 72 hours of operation. This composite also showed a moderate thermal expansion coefficient of 1.90 × 10−5 K−1 between 30°C and 1000°C and an electrical conductivity of at least 16 S cm−1 at 550°C and above. Modeling studies revealed that the oxygen permeation fluxes through 25SDC-75SCFZ are limited by surface exchange reactions from 700°C to 800°C and mixed bulk diffusion and surface exchange reactions above 800°C. 相似文献
18.
Brianna L. Musicó Quinton Wright Cordell Delzer T. Zac Ward Claudia J. Rawn David G. Mandrus Veerle Keppens 《Journal of the American Ceramic Society》2021,104(7):3750-3759
The multicomponent approach has been successfully expanded to the Ruddlesden–Popper structure with the synthesis of two different high-entropy cuprate compositions: (La0.2Nd0.2Gd0.2Tb0.2Dy0.2)2CuO4 and (La0.2Pr0.2Nd0.2Sm0.2Eu0.2)2CuO4. The effect of synthesis method is explored using both solid-state reaction and polymeric steric entrapment (PSE) methods. It is found that PSE leads to more randomly distributed cation species, providing an advantageous method of synthesis for the growing field of high entropy oxides. In situ high-temperature x-ray diffraction tracks the amorphous to crystalline phase transformation in (La0.2Nd0.2Gd0.2Tb0.2Dy0.2)2CuO4 powder, synthesized using the PSE method. Using the High-Temperature XRD data, a method for gaining information on the kinetic behavior is also applied. Magnetometry of both compositions indicates ferrimagnetic behavior at low temperatures. 相似文献
19.
Edward J. Daniels Joseph A. CarpenterJr. Claudia Duranceau Michael Fisher Candace Wheeler Gerald Winslow 《JOM Journal of the Minerals, Metals and Materials Society》2004,56(8):28-32
Approximately 15 million cars and trucks reach the end of their useful life in the United States each year. More than 75%
of the materials from end-of-life vehicles are profitably recovered and recycled by the private sector; automotive materials
recycling is a success story. To achieve greater fuel efficiency and safety, today’s cars incorporate an increasing share
of innovative light-weight materials. While these materials greatly enhance efficiency during vehicle use, they can present
special challenges for recycling. These challenges will persist as automotive designs and the mix of materials used in vehicles
continue evolving to further improve safety and performance. To meet the challenges of automotive materials recycling, the
U.S. Department of Energy has recently expanded its collaborative research with industry in this area. This article discusses
this collaborative government/industry approach to sustainable end-of-life vehicle recycling.
For more information, contact Edward J. Daniels, Argonne National Laboratory, 9700 S. Cass Avenue, Building 362, Room C393,
Argonne, IL 60439-4815; (630) 252-5279; fax (630) 252-1342; e-mail edaniels@anl.gov. 相似文献
20.
Fluorescence lifetime imaging (FLIM) is a powerful microscopy technique for providing contrast of biological and other systems by differences in molecular species or their environments. However, the cost of equipment and the complexity of data analysis have limited the application of FLIM. We present a mathematical model and physical implementation for a low cost digital frequency domain FLIM (DFD-FLIM) system, which can provide lifetime resolution with quality comparable to time-correlated single photon counting methods. Our implementation provides data natively in the form of phasors. On the basis of the mathematical model, we present an error analysis that shows the precise parameters for maximizing the quality of lifetime acquisition, as well as data to support this conclusion. The hardware and software of the proposed DFD-FLIM method simplifies the process of data acquisition for FLIM, presents a new interface for data display and interpretation, and optimizes the accuracy of lifetime determination. 相似文献