The flow structures and their interactions behind side-by-side cylinders of unequal diameters at small gap ratios are studied by dye-flow visualization and particle image velocimetry at Reynolds number 1000. The whole-field mean and fluctuating velocity distributions and evolutions in the wakes are studied by the particle image velocimetry. As the gap ratio decreases, the mutual interaction of the wakes behind side-by-side cylinders pushes the recirculation region behind the large cylinder farther downstream at the expense of deterioration of the wake behind small cylinder. This change is important and may be relevant to the applications of passive flow control strategy.

关键词：并排侧缸；小的差距比；不等径

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Deformation substructures control plastic, creep, fatigue and fracture properties of ductile crystalline solids. The key ingredient of a substructure is a spontaneously formed dislocation arrangement - dislocation structure. The present notes provide 5 different, complementary points of view which present the dislocation structure formation as a multi scale phenomenon: (ⅰ) The basic concepts of dislocation theory and plasticity of single crystals and polycrystals (Section 2). (ⅱ) A "gallery" of commented pictures of dislocation structures as seen by a transmission electron microscope (Section 3). (ⅲ) Discrete dislocation dynamics (Section 4). (ⅳ) An attempt to formulate statistics of dislocations as a transition from discrete dislocation dynamics to continuum crystal plasticity capable of modeling dislocation structure formation (Section 5). (ⅴ) Two continuous models of dislocation structure formation: one dimensional model simulating a formation of vein structure and its transformation into a ladder structure of a persistent slip band (Section 6.1), and a model of misoriented dislocation cells (Section 6.2).

关键词：变形子控制；韧性结晶固体胶；静脉结构

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In this paper, a novel active CRLH (Composite Right-Left Handed)Meta-material Antenna for cognitive radio using RF-MEMS (Micro-Electro-Mechanical-Systems) switches to realize reconfigurable radiation patterns is reported. The meta-materil consists of periodical J-shape patterns which have a CRLH (Composite Right Left Hand) property. RF-MEMS switches are used in each CRLH unit to tune the dispersion property. By discretely actuating the RF-MEMS switches through the DC feed voltage, its dispersion property is controlled, and the radiation pattern are tuned from the backward radiation to the broad-side and finally to forward in the frequency range between 9.55 GHz and 9.75 GHz. In addtition, different methods of RF-MEMS and antenna integration are discussed, and the number of RF-MEMS switches in each unit is studiud. The siginificance of MEMS switches to gain enhancement for reconfigurable antenna is investigated for the first time.

关键词：CRLH（复合右键左撇子）；可调超常材料；RF-MEMS；认知无线电

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Measuring PM Emissions from Aircraft Auxiliary Power Units, Tires, and Brakes presents the results of a comprehensive test program designed to measure particulate matter (PM) emissions from auxiliary power units and from tires and brakes during the landing phase of operations of in-service commercial aircraft. The research results are designed to provide a significant contribution to the characterization of emissions from these sources with the goal of helping airports improve the accuracy of their PM emissions inventories.

关键词：大气；PM排放；空气污染

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Urban mobility is not only one of the pillars of modern economic systems, but also a key issue in the quest for equality of opportunity, once it can improve access to other services. Currently, however, there are a number of negative issues related to traffic, especially in mega-cities, such as economical issues (cost of opportunity caused by delays), environmental (externalities related to emissions of pollutants), and social (traffic accidents). Solutions to these issues are more and more closely tied to information and communication technology. Indeed, a search in the technical literature (using the keyword "urban traffic" to filter out articles on data network traffic) retrieved the following number of articles (as of December 3, 2013): 9,443 (ACM Digital Library), 26,054 (Scopus), and 1,730,000 (Google Scholar). Moreover, articles listed in the ACM query relate to conferences as diverse as MobiCom, CHI, PADS, and AAMAS. This means that there is a big and diverse community of computer scientists and computer engineers who tackle research that is connected to the development of intelligent traffic and transportation systems. It is also possible to see that this community is growing, and that research projects are getting more and more interdisciplinary. To foster the cooperation among the involved communities, this book aims at giving a broad introduction into the basic but relevant concepts related to transportation systems, targeting researchers and practitioners from computer science and information technology. In addition, the second part of the book gives a panorama of some of the most exciting and newest technologies, originating in computer science and computer engineering, that are now being employed in projects related to car-to-car communication, interconnected vehicles, car navigation, platoon-ing, crowd sensing and sensor networks, among others. This material will also be of interest to engineers and researchers from the traffic and transportation community.

关键词：智能交通系统；交通模型；交通仿真

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Because of its minor environmental impact, electricity generation using wind power is getting remarkable. The further growth of the wind industry depends on technological solutions to the challenges in production and construction of the turbines. Wind turbine tower vibrations, which limit power generation efficiency and cause fatigue problems with high maintenance costs, count as one of the main structural difficulties in the wind energy sector. To mitigate tower vibrations auxiliary measures are necessary. The effectiveness of tuned mass damper is verified by means of a numeric study on a 5 MW onshore reference wind turbine. Hereby, also seismic-induced vibrations and soil-structure interaction are considered. Acquired results show that tuned mass damper can effectively reduce resonant tower vibrations and improve the fatigue life of wind turbines. This chapter is also concerned with tuned liquid column damper and a semiactive application of it. Due to its geometric versatility and low prime costs, tuned liquid column dampers are a good alternative to other damping measures, in particular for slender structures like wind turbines.

关键词：结构控制；调谐质量阻尼器；调液阻尼器

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Robust controller synthesis is of great practical interest and its automation is a key concern in control system design. Automatic controller synthesis is still a open problem. In this paper a new, efficient method has been proposed for automated synthesis of a fixed structure quantitative feedback theory (QFT) controller by solving QFT quadratic inequalities of robust stability and performance specifications. The controller synthesis problem is posed as interval constraint satisfying problem (ICSP) and solved with interval constraint solver (realpaver) . The method is guaranteed to find all feasible controllers of given structure in the search domain. The controller designed using proposed method is experimentally tested on ECP's Magnetic Levitation system which has open loop stable and unstable configurations.

关键词：鲁棒控制;QFT;自动回路成形;约束传播

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Creating transportation infrastructure, which can clean up itself and contaminated air surrounding it, can be a groundbreaking approach in addressing environmental challenges of our time. This project has explored a possibility of depositing coatings on the existing materials to address a feasibility of this approach. More specifically, we have quantified the rates of removal of pollutants from the air by a new generation of coatings, which can be applied on any architectural elements and transportation infrastructure. We have also used indicators synthesized in our lab to demonstrate the self-cleaning properties of these now commercially available coatings. In addition, we have worked with the company pioneering this technology in the US and Europe to scope the new application of this technology. The survey of the existing and future commercial projects has indicated that this technology is already leading to very exciting applications in transportation sector, where concrete, asphalt, steel, glass and masonry surfaces will become green and sustainable interfaces mitigating the environmental and health impacts of transportation. The results obtained in this project have a significant relevance to the USDOT goals, such as development of livable communities by providing an access to environmentally sustainable travel options. Moreover, it has also relevance to another DOT goal focused on environmental sustainability, where self-cleaning properties of the coatings have a potential to improve both energy and water conservation.

关键词：大气；空气治理；空气净化

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Project attempts to develop a synthetic analogue for carbonic anhydrase and incorporate it in a membrane for separation of CO2 from coal power plant flue gas. Conference poster presents result of first 9 months of project progress including concept, basic system architecture and membrane properties target, results of molecular modeling for analogue - CO2 interaction, and next steps of testing analogue resistance to flue gas contaminants.

关键词：大气；气体循环；废气重利用

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The overall goal of the project was to bridge the gap between our knowledge of small-scale geochemical reaction rates and reaction rates meaningful for modeling transport at core scales. The working hypothesis was that reaction rates, determined from laboratory measurements based upon reactions typically conducted in well mixed batch reactors using pulverized reactive media may be significantly changed in in situ porous media flow due to rock microstructure heterogeneity. Specifically we hypothesized that, generally, reactive mineral surfaces are not uniformly accessible to reactive fluids due to the random deposition of mineral grains and to the variation in flow rates within a pore network. Expected bulk reaction rates would therefore have to be correctly up-scaled to reflect such heterogeneity. The specific objective was to develop a computational tool that integrates existing measurement capabilities with pore-scale network models of fluid flow and reactive transport. The existing measurement capabilities to be integrated consisted of (a) pore space morphology, (b) rock mineralogy, and (c) geochemical reaction rates. The objective was accomplished by: (1) characterizing sedimentary sandstone rock morphology using X-ray computed microtomography, (2) mapping rock mineralogy using back-scattered electron microscopy (BSE), X-ray dispersive spectroscopy (EDX) and CMT, (3) characterizing pore-accessible reactive mineral surface area, and (4) creating network models to model acidic CO(sub 2) saturated brine injection into the sandstone rock samples.

关键词：大气；二氧化碳；温室气体

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