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31.
Gumennik A Ilan H Fathei R Israel A Agranat AJ Shachar I Hass M 《Applied optics》2007,46(19):4132-4137
Slab waveguides were constructed in K(1-x)Li(x)Ta(1-y)Nb(y)O(3) crystals by the implantation of (12)C(+4) ions at 30 MeV and (16)O(+5) ions at 30 and 40 MeV. The waveguides were characterized by a prism coupler setup. A refractive index drop of 10.9% was observed in a layer formed by the implantation of (16)O(+5) ions at 30 MeV. The carbon-implanted waveguides were found to be thermally stable after annealing at 450 degrees C. A semiempirical formula for predicting the change in the refractive index given the parameters of the implantation process was developed. It is argued that the combination of the basic implantation process with the semiempirical formula can be developed to become a generic method for constructing complex electro-optic circuits with a wave-guided architecture. 相似文献
32.
We introduce a novel method for visual homing. Using this method a robot can be sent to desired positions and orientations in 3D space specified by single images taken from these positions. Our method is based on recovering the epipolar geometry relating the current image taken by the robot and the target image. Using the epipolar geometry, most of the parameters which specify the differences in position and orientation of the camera between the two images are recovered. However, since not all of the parameters can be recovered from two images, we have developed specific methods to bypass these missing parameters and resolve the ambiguities that exist. We present two homing algorithms for two standard projection models, weak and full perspective.Our method determines the path of the robot on-line, the starting position of the robot is relatively not constrained, and a 3D model of the environment is not required. The method is almost entirely memoryless, in the sense that at every step the path to the target position is determined independently of the previous path taken by the robot. Because of this property the robot may be able, while moving toward the target, to perform auxiliary tasks or to avoid obstacles, without this impairing its ability to eventually reach the target position. We have performed simulations and real experiments which demonstrate the robustness of the method and that the algorithms always converge to the target pose. 相似文献
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34.
Electric vehicles (EVs) present efficiency and environmental advantages over conventional transportation. It is expected that in the next decade this technology will progressively penetrate the market. The integration of plug-in electric vehicles in electric power systems poses new challenges in terms of regulation and business models. This paper proposes a conceptual regulatory framework for charging EVs. Two new electricity market agents, the EV charging manager and the EV aggregator, in charge of developing charging infrastructure and providing charging services are introduced. According to that, several charging modes such as EV home charging, public charging on streets, and dedicated charging stations are formulated. Involved market agents and their commercial relationships are analysed in detail. The paper elaborates the opportunities to formulate more sophisticated business models for vehicle-to-grid applications under which the storage capability of EV batteries is used for providing peak power or frequency regulation to support the power system operation. Finally penetration phase dependent policy and regulatory recommendations are given concerning time-of-use pricing, smart meter deployment, stable and simple regulation for reselling energy on private property, roll-out of public charging infrastructure as well as reviewing of grid codes and operational system procedures for interactions between network operators and vehicle aggregators. 相似文献
35.
Assoc. Prof. Jing Li Prof. Ilan Vertinsky Asst. Prof. Hua Zhang 《Management International Review》2013,53(3):361-390
- Does the quality of domestic legal institutions matter for export performance? How does differential access to protections and privileges offered by informal institutions moderate the relationship between the quality of formal legal institutions and export performance? To answer these questions, we develop a theoretical framework drawing on insights from trade theory and institutional theory.
- We propose that higher-quality legal systems in an exporter’s location are associated with higher export performance, particularly when trade partners face higher levels of external and internal uncertainty. We further propose that firms that have less access to local informal institutions to reduce transaction costs and opportunism benefit more from better-developed legal institutions.
- Using information for more than 198,000 firms and legal quality information for 120 cities in China, we find strong support for our predictions. We discuss our contributions to the literature on institutions and export.
36.
The authors examined the associations between internalized homophobia, outness, community connectedness, depressive symptoms, and relationship quality among a diverse community sample of 396 lesbian, gay, and bisexual (LGB) individuals. Structural equation models showed that internalized homophobia was associated with greater relationship problems both generally and among coupled participants independent of outness and community connectedness. Depressive symptoms mediated the association between internalized homophobia and relationship problems. This study improves present understandings of the association between internalized homophobia and relationship quality by distinguishing between the effects of the core construct of internalized homophobia and its correlates and outcomes. The findings are useful for counselors interested in interventions and treatment approaches to help LGB individuals cope with internalized homophobia and relationship problems. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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38.
Adam M. Stoklosa Ilan Weiss Bruce Bugbee Michele H. Perchonok 《International Journal of Food Properties》2013,16(5):996-1006
Long duration space missions may include dwarf wheat cultivars to meet closed-loop food system constraints. Composition and functional properties of dwarf wheats (Apogee, Perigee) were characterized and compared to terrestrial cultivars (Parshall, Yecora Rojo, Yavaros 79). Proximate composition was determined using standard methods, and functional attributes were evaluated by mixograph and pasting profiles. Additional analyses measured antioxidant capacity, protein profiles, non-protein nitrogen, lipid oxidation, and starch damage. Apogee and Perigee were compositionally and functionally different from traditional cultivars, having higher protein (18–20%), ash (2–2.4%), and antioxidant (Perigee had 23.7 mol Trolox equivalent/g), and lipid oxidation levels but lower protein quality indicators. There was significant correlation (R2 = 0.84) between ash content and lipid oxidation. Apogee is a better candidate crop than Perigee for a self sustaining environment, but both dwarf varieties could be used for tailored food applications. 相似文献
39.
Ilan Riess Jeremy Rutman Zvi Rosenstock 《Journal of the American Ceramic Society》2001,84(12):2895-2899
Using solid materials prepared by melting or sintering allows inert metal electrodes to be embedded inside the solid. The I–V relations for four linear electrodes embedded inside a rectangular sample are evaluated. Two cases are considered: (a) a sample with uniform electronic (electron/hole) conductivity and (b) the electron/hole partial current in a sample that is a mixed ionic-electronic conductor with a nonuniform electron/hole distribution. Equations are derived which allow the determination of the conductivity from four-electrode measurements if a pure electronic conductor is considered or if a mixed ionic-electronic conductor is considered with the ionic current being blocked. 相似文献
40.
Seyed Mohammad Reza Paran Henri Vahabi Maryam Jouyandeh Franck Ducos Krzysztof Formela Mohammad Reza Saeb 《应用聚合物科学杂志》2019,136(20):47483
Thermally stable thermoplastic elastomer nanocomposites based on polyamide 6 (PA6), acrylonitrile butadiene rubber (NBR), and halloysite nanotubes (HNTs) were dynamically vulcanized, and their nonisothermal decomposition kinetics were examined. The Friedman, Kissinger–Akahira–Sunose (KAS), Ozawa–Wall–Flynn (FWO), and modified Coats–Redfern (m-CR) isoconversional models were used to obtain information about the kinetics of the thermal decomposition of PA6–NBR–HNTs in terms of the activation energy per partial mass loss monitored through thermogravimetric analyses performed at different heating rates. An erratic trend was due to the Friedman model, especially for systems having higher HNT loadings, whereas the KAS, FWO, and m-CR models revealed very similar meaningful thermal decomposition kinetics. A relatively high activation energy corroborating a reliable thermal stability was obtained by the addition of HNTs to PA6–NBR, and the resistance against decomposition was higher for systems containing more HNT. This signified the role of the HNTs as thermal stability modifiers. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47483. 相似文献