WorldWideScience

Sample records for bituminous overlays

  1. Evaluation of the Properties of Bituminous Concrete Prepared from Brick-Stone Mix Aggregate

    OpenAIRE

    Dipankar Sarkar; Manish Pal; Sarkar, Ashoke K.; Umesh Mishra

    2016-01-01

    The paper describes an investigation into mechanical properties of brick-stone bituminous concrete mix. The effect of brick-stone mix on various mechanical properties of the bituminous concrete such as Marshall stability, flow, Marshall Quotient (stability to flow ratio), Indirect Tensile Strength, stripping, rutting, and fatigue life of bituminous concrete overlay has been evaluated. In this study over-burnt brick aggregate (OBBA) and stone aggregate (SA) have been mixed in different ratios ...

  2. Evaluation of the Properties of Bituminous Concrete Prepared from Brick-Stone Mix Aggregate

    Directory of Open Access Journals (Sweden)

    Dipankar Sarkar

    2016-01-01

    Full Text Available The paper describes an investigation into mechanical properties of brick-stone bituminous concrete mix. The effect of brick-stone mix on various mechanical properties of the bituminous concrete such as Marshall stability, flow, Marshall Quotient (stability to flow ratio, Indirect Tensile Strength, stripping, rutting, and fatigue life of bituminous concrete overlay has been evaluated. In this study over-burnt brick aggregate (OBBA and stone aggregate (SA have been mixed in different ratios (by weight such as 20 : 80, 40 : 60, 60 : 40, and 80 : 20, respectively. The laboratory results indicate that bituminous concrete, prepared by 20% brick aggregate and 80% stone aggregate, gives the highest Marshall stability. This bituminous concrete mix shows considerable improvement in various mechanical properties of the mix as compared to the other mixes.

  3. Bituminous sands : tax issues

    Energy Technology Data Exchange (ETDEWEB)

    Patel, B. [PricewaterhouseCoopers LLP, Calgary, AB (Canada)

    2004-07-01

    This paper examined some of the tax issues associated with the production of bitumen or synthetic crude oil from oil sands. The oil sands deposits in Alberta are gaining more attention as the supplies of conventional oil in Canada decline. The oil sands reserves located in the Athabasca, Cold Lake and Peace River areas contain about 2.5 trillion barrels of highly viscous hydrocarbons called bitumen, of which nearly 315 billion barrels are recoverable with current technology. The extraction method varies for each geographic area, and even within zones and reservoirs. The two most common extraction methods are surface mining and in-situ extraction such as cyclic steam stimulation (CSS); low pressure steam flood; pressure cycle steam drive; steam assisted gravity drainage (SAGD); hot water flooding; and, fire flood. This paper also discussed the following general tax issues: bituminous sands definition; bituminous sands leases and Canadian development expense versus Canadian oil and gas property expense (COGPE); Canadian exploration expense (CEE) for surface mining versus in-situ methods; additional capital cost allowance; and, scientific research and experimental development (SR and ED). 15 refs.

  4. Effect of Cement on Properties of Over-Burnt Brick Bituminous Concrete Mixes

    Science.gov (United States)

    Sarkar, Dipankar; Pal, Manish

    2016-06-01

    The present investigation is carried out to propose the use of cement coated over burnt brick aggregate in the preparation of bituminous concrete mix. The effect of cement on various mechanical properties such as Marshall stability, flow, Marshall quotient (stability to flow ratio), indirect tensile strength, stripping, rutting and fatigue life of bituminous concrete overlay has been evaluated. In this study, different cement percentages such as 2, 3, 4 and 5 % by weight of aggregate have been mixed with Over Burnt Brick Aggregate (OBBA). The laboratory results indicate that bituminous concrete prepared by 4 % cement coated OBBA gives the highest Marshall stability. The bituminous concrete mix with 4 % cement shows considerable improvement in various mechanical properties of the mix compared to the plain OBBA concrete mix.

  5. RADAR PPI Scope Overlay

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — RADAR PPI Scope Overlays are used to position a RADAR image over a station at the correct resolution. The archive maintains several different RADAR resolution types,...

  6. New holographic overlays

    Science.gov (United States)

    Hopwood, Anthony I.

    1991-10-01

    This paper discusses a new type of holographic overlay, FLASHPRINT, which may be used in both security and packaging applications. Unlike the more common embossed holograms currently used, FLASHPRINT leads to reduced set-up costs and offers a simpler process. This reduces the long lead times characteristic of the existing technology and requires the customer to provide only two-dimensional artwork. The overlay material contains a covert 2-D image. The image may be switched on or off by simply tilting the overlay in a light source. The overlay is replayed in the 'on' position to reveal the encoded security message as a highly saturated gold colored image. This effect is operable for a wide range of lighting conditions and viewing geometries. In the 'off' position the overlay is substantially transparent. These features make the visual effect of the overlay attractive to incorporate into product design. They may be laminated over complex printed artwork such as labels and security passes without masking the printed message. When switched 'on' the image appears both sharp and more than seven times brighter than white paper. The image remains sharp and clear even in less favorable lighting conditions. Although the technique offers a low set-up cost for the customer, through its simplicity, it remains as technically demanding and difficult to counterfeit as any holographic process.

  7. Overlay mark optimization for thick-film resist overlay metrology

    Institute of Scientific and Technical Information of China (English)

    Zhu Liang; Li Jie; Zhou Congshu; Gu Yili; Yang Huayue

    2009-01-01

    For thick resist implant layers, such as a high voltage P well and a deep N well, systematic and uncorrectable overlay residues brought about by the tapered resist profiles were found. It was found that the tapered profile is closely related to the pattern density. Potential solutions of the manufacturing problem include hardening the film solidness or balancing the exposure density. In this paper, instead of focusing on the process change methodology,we intend to solve the issue of the overlay metrology error from the perspective of the overlay mark design. Based on the comparison of the overlay performances between the proposed overlay mark and the original design, it is shown that the optimized overlay mark target achieves better performance in terms of profiles, dynamic precision,tool induced shift (TIS), and residues. Furthermore, five types of overlay marks with dummy bars are studied, and a recommendation for the overlay marks is given.

  8. Overlay networks toward information networking

    CERN Document Server

    Tarkoma, Sasu

    2010-01-01

    With their ability to solve problems in massive information distribution and processing, while keeping scaling costs low, overlay systems represent a rapidly growing area of R&D with important implications for the evolution of Internet architecture. Inspired by the author's articles on content based routing, Overlay Networks: Toward Information Networking provides a complete introduction to overlay networks. Examining what they are and what kind of structures they require, the text covers the key structures, protocols, and algorithms used in overlay networks. It reviews the current state of th

  9. Towards Social Profile Based Overlays

    CERN Document Server

    Wolinsky, David Isaac; Boykin, P Oscar; Figueiredo, Renato

    2010-01-01

    Online social networking has quickly become one of the most common activities of Internet users. As social networks evolve, they encourage users to share more information, requiring the users, in turn, to place more trust into social networks. Peer-to-peer (P2P) overlays provide an environment that can return ownership of information, trust, and control to the users, away from centralized third-party social networks. In this paper, we present a novel concept, social profile overlays, which enable users to share their profile only with trusted peers in a scalable, reliable, and private manner. Each user's profile consists of a unique private, secure overlay, where members of that overlay have a friendship with the overlay owner. Profile data is made available without regard to the online state of the profile owner through the use of the profile overlay's distributed data store. Privacy and security are enforced through the use of a public key infrastructure (PKI), where the role of certificate authority (CA) i...

  10. Radon concentration measurements in bituminous coal mines.

    Science.gov (United States)

    Fisne, Abdullah; Okten, Gündüz; Celebi, Nilgün

    2005-01-01

    Radon measurements were carried out in Kozlu, Karadon and Uzülmez underground coal mines of Zonguldak bituminous coal basin in Turkey. Passive-time integrating method, which is the most widely used technique for the measurement of radon concentration in air, was applied by using nuclear etched track detectors (CR-39) in the study area. The radon concentration measurements were performed on a total of 42 points in those three mines. The annual exposure, the annual effective dose and lifetime fatality risk, which are the important parameters for the health of workers, were estimated based on chronic occupational exposure to the radon gas, which is calculated using UNCEAR-2000 and ICRP-65 models. The radon concentrations at several coal production faces are higher than the action level of 1000 Bq m(-3). It is suggested that the ventilation rates should be rearranged to reduce the radon concentration.

  11. Facies studies of bituminous coals in Poland

    Energy Technology Data Exchange (ETDEWEB)

    Nowak, Grzegorz J. [Polish Geological Institute, Lower Silesian Branch, al. Jaworowa 19, 53-122, Wroclaw (Poland)

    2004-04-23

    Polish bituminous coal basins are associated exclusively with Carboniferous deposits, differing in origin and geological structure. This paper presents only short review of papers of Polish authors on coal facies studies of Carboniferous coals occurring in the Lower Silesian Coal Basin (LSCB), Upper Silesian Coal Basin (USCB) and Lublin Coal Basin (LCB) of Poland. Facies investigations of Carboniferous coals of Poland have been in progress over 20 years. The results of these studies have provided new information on such subjects as: (1) recognition of main depositional conditions in paleomires, (2) determine prevailing paleoplant communities, (3) appraisal of peat-forming environment reconstruction-types and characteristics of paleomires. These facies analyses are connected to results of such studies as: pure coal petrology, using maceral and microlithotype composition as parameters of the environment of coal deposition, combined results of petrological, palynological and sedimentological studies.

  12. Culture systems: mineral oil overlay.

    Science.gov (United States)

    Morbeck, Dean E; Leonard, Phoebe H

    2012-01-01

    Mineral oil overlay microdrop is commonly used during in vitro fertilization (IVF) procedures. Though mineral oil appears homogeneous, it is an undefined product that can vary in quality. Here, we describe the history, chemistry, processing, and optimal use of mineral oil for IVF and embryo culture.

  13. EXPERIMENTAL STUDY ON HORIZONTAL COMBUSTION TECHNIQUE FOR BITUMINOUS COAL BRIQUET

    Institute of Scientific and Technical Information of China (English)

    路春美; 程世庆; 邵延玲; 张晔

    1997-01-01

    Through a lot of experiments, a new kind of stove using horizontal combustion technique for bituminous coal briquet has been developed. Making use of this stove, studies have been made on burning process of bituminous coal briquet, distribution of temperature field in the stove, the regularities of evolution and combustion of volatile matter, the burning rate and efficiency of bituminous coal briquet, characteristics of fire-sealing and sulfur-retention. The results show that, with the technique, some achievements can be obtained in combustion of bituminous coal briquet, such as lower pollution that the flue gas black degree is below 0.5R and dust concentration is below 90mg/m3 . The stove's combustion efficiency reaches 90%, sulfur fixing efficiency is 60%, and CO concentration is decreased by 40% compared with other traditional stoves. With so many advantages, the stove can be used extensively in civil stoves and smaller industrial boilers.

  14. Modification Bituminous Binders Petroleum Resin (Based on C9 Fraction

    Directory of Open Access Journals (Sweden)

    Elena A. Chigorina

    2015-12-01

    Full Text Available The goal of the present study is to measure the basic parameters of a bituminous binder obtained by modification of the BND 60/90 binder with petroleum resin, for both dynamic and static modification modes.

  15. Effects of bituminous layer as backfill material on mechanical behavior in tunnel model

    OpenAIRE

    Moriyoshi, Akihiro; Takano, Shin-ei; Urata, Hiroyuki; Suzuki, Tetsuya; Yoshida, Takaki

    2001-01-01

    This paper describes the effects of bituminous material as a backfill material on mechanical behavior in model tunnel in laboratory. It is known that load spreading and relaxation of bituminous material are good properties. Then if we use bituminous material as a backfill material of tunnel, the tunnel will have waterproof, good load spreading property. We used new bituminous material (Aquaphalt) which can solidify in water. We conducted relaxation test in tension for new bituminous mat...

  16. The bituminous sands : a Canadian mirage?

    Energy Technology Data Exchange (ETDEWEB)

    Rousse, D.R. [Quebec Univ., Chicoutimi, PQ (Canada). Dept. des Sciences Appliquees; Nasr, G.J. [Lebanese Univ., Roumieh (Lebanon). Faculty of Engineering; Turcotte, S.F. [Quebec Univ., Montreal, PQ (Canada). Centre d' Etudes Internationales et Mondialisation; Salah, N.B. [Ecole Superieure des Sciences et Techniques De Tunis, Tunis (Tunisia). LMMP

    2009-07-01

    This paper examined the controversy about the potential role of a significant increase in Canadian oil sands production in order to bridge the upcoming gap between the world's increasing energy demand and the total recoverable oil supply. The paper presented the actual potential of different scenarios and considered the prediction cost forecasts. A brief overview of environmental impacts and the real return on investments were also provided. Environmental impacts that were considered included land degradation; water contamination; ecosystem damage; and air pollution. Nuclear energy was also presented as a possible solution. The paper demonstrated that even in a very optimistic scenario, Canada's oil sands accelerated production has a negligible effect on the aforementioned gap, has a considerable impact on environment that has yet to be accounted for. Energy ratios that were presented included energy return on energy investment; energy available on energy used; and energy payback. It was concluded that enhanced recovery techniques are clearly needed for future sustainable exploitation of these bituminous sands. 32 refs., 1 fig.

  17. Advanced overlay analysis through design based metrology

    Science.gov (United States)

    Ji, Sunkeun; Yoo, Gyun; Jo, Gyoyeon; Kang, Hyunwoo; Park, Minwoo; Kim, Jungchan; Park, Chanha; Yang, Hyunjo; Yim, Donggyu; Maruyama, Kotaro; Park, Byungjun; Yamamoto, Masahiro

    2015-03-01

    As design rule shrink, overlay has been critical factor for semiconductor manufacturing. However, the overlay error which is determined by a conventional measurement with an overlay mark based on IBO and DBO often does not represent the physical placement error in the cell area. The mismatch may arise from the size or pitch difference between the overlay mark and the cell pattern. Pattern distortion caused by etching or CMP also can be a source of the mismatch. In 2014, we have demonstrated that method of overlay measurement in the cell area by using DBM (Design Based Metrology) tool has more accurate overlay value than conventional method by using an overlay mark. We have verified the reproducibility by measuring repeatable patterns in the cell area, and also demonstrated the reliability by comparing with CD-SEM data. We have focused overlay mismatching between overlay mark and cell area until now, further more we have concerned with the cell area having different pattern density and etch loading. There appears a phenomenon which has different overlay values on the cells with diverse patterning environment. In this paper, the overlay error was investigated from cell edge to center. For this experiment, we have verified several critical layers in DRAM by using improved(Better resolution and speed) DBM tool, NGR3520.

  18. Overlay networking:applications and research challenges

    Institute of Scientific and Technical Information of China (English)

    LU Jun-xiu; SHAN Xiu-ming; REN Yong

    2004-01-01

    Overlay networking is one of the perspective solutions to today's Intemet challenges. At basic service level, overlay networks can serve as a supplement and enhancement of existing services, such as routing and addressing. At high application level, overlay networks can be used for applications, which are difficult to deploy in existing IP architecture with some specific reasons, e.g., they need high-level information, which is hard to obtain by underlying layers. To address the heterogeneity of today's Internet, overlay networks provide ways to service availability and desirable performance while retaining scalability. In contrast to changing the existing network layer, overlay networks allow bootstrapping, which is most important in the development of Internet infrastructure. Various applications of overlay networking are clarified in this paper. Research challenges including routing and searching in overlay networking are also identified.

  19. Overlay metrology for double patterning processes

    Science.gov (United States)

    Leray, Philippe; Cheng, Shaunee; Laidler, David; Kandel, Daniel; Adel, Mike; Dinu, Berta; Polli, Marco; Vasconi, Mauro; Salski, Bartlomiej

    2009-03-01

    The double patterning (DPT) process is foreseen by the industry to be the main solution for the 32 nm technology node and even beyond. Meanwhile process compatibility has to be maintained and the performance of overlay metrology has to improve. To achieve this for Image Based Overlay (IBO), usually the optics of overlay tools are improved. It was also demonstrated that these requirements are achievable with a Diffraction Based Overlay (DBO) technique named SCOLTM [1]. In addition, we believe that overlay measurements with respect to a reference grid are required to achieve the required overlay control [2]. This induces at least a three-fold increase in the number of measurements (2 for double patterned layers to the reference grid and 1 between the double patterned layers). The requirements of process compatibility, enhanced performance and large number of measurements make the choice of overlay metrology for DPT very challenging. In this work we use different flavors of the standard overlay metrology technique (IBO) as well as the new technique (SCOL) to address these three requirements. The compatibility of the corresponding overlay targets with double patterning processes (Litho-Etch-Litho-Etch (LELE); Litho-Freeze-Litho-Etch (LFLE), Spacer defined) is tested. The process impact on different target types is discussed (CD bias LELE, Contrast for LFLE). We compare the standard imaging overlay metrology with non-standard imaging techniques dedicated to double patterning processes (multilayer imaging targets allowing one overlay target instead of three, very small imaging targets). In addition to standard designs already discussed [1], we investigate SCOL target designs specific to double patterning processes. The feedback to the scanner is determined using the different techniques. The final overlay results obtained are compared accordingly. We conclude with the pros and cons of each technique and suggest the optimal metrology strategy for overlay control in double

  20. Investigation of synthesis of silicon carbide from bituminous coal

    Energy Technology Data Exchange (ETDEWEB)

    Wang, X.; He, E.; Chen, S. [Xian University of Science and Technology, Xian (China). Dept of Materials Technology

    2000-08-01

    Three kinds of bituminous coal were investigated in SiC synthesis reaction under N{sub 2} atmosphere protection. It was found that bituminous coal could be used as the carbon source to synthesise SiC. However, there was a significant difference in the quantity of SiC and Si{sub 3}N{sub 4}, which was the by product, from the different types of bituminous coal. It had been indicated by the research work that the bituminous coal's volatile constituents and the micro-structure of the coke (such as porosity, micromorphology of pore and specific surface area etc.) were the two critical factors which determined the generation of SiC and Si{sub 3}N{sub 4} in this reaction system. The difference of these three kinds of bituminous coal in volatile constituents and coke's micro-structure were studied under temperature ranging from 1200 to 1600{degree}C and their effects on the SiC reaction system was also discussed. 6 refs., 5 figs., 2 tabs.

  1. Investigation of plasma-aided bituminous coal gasification

    Energy Technology Data Exchange (ETDEWEB)

    Matveev, I.B.; Messerle, V.E.; Ustimenko, A.B. [Applied Plasma Technology, Mclean, VA (United States)

    2009-04-15

    This paper presents thermodynamic and kinetic modeling of plasma-aided bituminous coal gasification. Distributions of concentrations, temperatures, and velocities of the gasification products along the gasifier are calculated. Carbon gasification degree, specific power consumptions, and heat engineering characteristics of synthesis gas at the outlet of the gasifier are determined at plasma air/steam and oxygen/steam gasification of Powder River Basin bituminous coal. Numerical simulation showed that the plasma oxygen/steam gasification of coal is a more preferable process in comparison with the plasma air/steam coal gasification. On the numerical experiments, a plasma vortex fuel reformer is designed.

  2. A study on spontaneous ignition of bituminous coal

    Energy Technology Data Exchange (ETDEWEB)

    Xin-Rui Li; Hiroshi Koseki; Yusaku Iwata [National Research Institute of Fire and Disaster, Tokyo (Japan)

    2009-07-01

    The thermal properties of four bituminous coals were studied using isothermal and temperature-programmed calorimeters, such as a differential thermal analysis, a heat flux calorimeter C80 and an thermal activity monitor (TAM-III). The corresponding spontaneous ignition was measured in an adiabatic spontaneous ignition tester. It was found that there were weak exothermic activities in bituminous coal at 50-100 {sup o}C and meanwhile carbon monoxide and carbon dioxide was generated. These thermal behaviors are responsible for the self heating from 50{sup o}C and spontaneous ignition at 80{sup o}C. 15 refs., 7 figs., 5 tabs.

  3. A study on spontaneous ignition of bituminous coal

    Directory of Open Access Journals (Sweden)

    Li Xin-Rui

    2009-01-01

    Full Text Available The thermal properties of four bituminous coals were studied using isothermal and temperature-programmed calorimeters, such as a differential thermal analysis, a heat flux calorimeter C80 and an thermal activity monitor (TAM-III. The corresponding spontaneous ignition was measured in an adiabatic spontaneous ignition tester. It was found that there were weak exothermic activities in bituminous coal at 50-100°C and meanwhile carbon monoxide and carbon dioxide was generated. These thermal behaviors are responsible for the self heating from 50°C and spontaneous ignition at 80°C.

  4. Analysis Of Overlay Distortion Patterns

    Science.gov (United States)

    Armitage, John D.; Kirk, Joseph P.

    1988-01-01

    A comprehensive geometrical approach is presented for the least-squares analysis of overlay distortion patterns into useful, physically meaningful systematic distortion subpatterns and an essentially non-systematic residue. A scheme of generally useful distortion sub-patterns is presented in graphic and algorithmic form; some of these sub-patterns are additions to those already in widespread use. A graphic and geometric approach is emphasized rather than an algebraic or statistical approach, and an example illustrates the value in utilizing the pattern-detecting ability of the eye-brain system. The conditions are described under which different distortion sub-patterns may interact, possibly leading to misleading or erroneous conclusions about the types and amounts of different distortions present. Examples of typical interaction situations are given, and recommendations are made for analytic procedures to avoid misinterpretation. It is noted that the lower-order distortion patterns preserve straight-line linearity, but that higher-order distortion may result in straight lines becoming curved. The principle of least-squares analysis is outlined and a simple polynomial data-fitting example is used to illustrate the method. Algorithms are presented for least-squares distortion analysis of overlay patterns, and an APL2 program is given to show how this may easily be implemented on a digital computer. The appendix extends the treatment to cases where small-angle approximation is not permissible.

  5. LMS filters for cellular CDMA overlay

    OpenAIRE

    1996-01-01

    This paper extends and complements previous research we have performed on the performance of nonadaptive narrowband suppression filters when used in cellular CDMA overlay situations. In this paper, an adaptive LMS filter is applied to cellular CDMA overlay situations in order to reject narrowband interference.

  6. Overlay accuracy with respect to device scaling

    Science.gov (United States)

    Leray, Philippe; Laidler, David; Cheng, Shaunee

    2012-03-01

    Overlay metrology performance is usually reported as repeatability, matching between tools or optics aberrations distorting the measurement (Tool induced shift or TIS). Over the last few years, improvement of these metrics by the tool suppliers has been impressive. But, what about accuracy? Using different target types, we have already reported small differences in the mean value as well as fingerprint [1]. These differences make the correctables questionable. Which target is correct and therefore which translation, scaling etc. values should be fed back to the scanner? In this paper we investigate the sources of these differences, using several approaches. First, we measure the response of different targets to offsets programmed in a test vehicle. Second, we check the response of the same overlay targets to overlay errors programmed into the scanner. We compare overlay target designs; what is the contribution of the size of the features that make up the target? We use different overlay measurement techniques; is DBO (Diffraction Based Overlay) more accurate than IBO (Image Based Overlay)? We measure overlay on several stacks; what is the stack contribution to inaccuracy? In conclusion, we offer an explanation for the observed differences and propose a solution to reduce them.

  7. KMPlayer出现Overlay Mixer错误

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    问:我使用KMPlayer播放器播放电影时,经常出现Overlay Mixer错误,有时候不出现,我将Overlay Mixer插件删除了,但它还会自动加载,继续出错。请问这是什么原因?

  8. Unexpectedly high uptake of palladium by bituminous coals

    Energy Technology Data Exchange (ETDEWEB)

    Lakatos, J. [Research Lab. for Mining Chemistry, Hungarian Academy of Sciences, Miskolc-Egyetemvaros (Hungary); Brown, S.D.; Snape, C.E. [Univ. of Strathclyde, Dept. of Pure and Applied Chemistry, Glasgow (United Kingdom)

    1997-12-31

    The uptake of palladium as a conversion catalyst onto coals of different rank was investigated. Palladium fixation occurs by a different mode to that for alkaline earth and first row transition metals. Therefore, the dispersion of relatively high concentration of palladium by an ion sorption process is even possible for bituminous coals. (orig.)

  9. Device overlay method for high volume manufacturing

    Science.gov (United States)

    Lee, Honggoo; Han, Sangjun; Kim, Youngsik; Kim, Myoungsoo; Heo, Hoyoung; Jeon, Sanghuck; Choi, DongSub; Nabeth, Jeremy; Brinster, Irina; Pierson, Bill; Robinson, John C.

    2016-03-01

    Advancing technology nodes with smaller process margins require improved photolithography overlay control. Overlay control at develop inspection (DI) based on optical metrology targets is well established in semiconductor manufacturing. Advances in target design and metrology technology have enabled significant improvements in overlay precision and accuracy. One approach to represent in-die on-device as-etched overlay is to measure at final inspection (FI) with a scanning electron microscope (SEM). Disadvantages to this approach include inability to rework, limited layer coverage due to lack of transparency, and higher cost of ownership (CoO). A hybrid approach is investigated in this report whereby infrequent DI/FI bias is characterized and the results are used to compensate the frequent DI overlay results. The bias characterization is done on an infrequent basis, either based on time or triggered from change points. On a per-device and per-layer basis, the optical target overlay at DI is compared with SEM on-device overlay at FI. The bias characterization results are validated and tracked for use in compensating the DI APC controller. Results of the DI/FI bias characterization and sources of variation are presented, as well as the impact on the DI correctables feeding the APC system. Implementation details in a high volume manufacturing (HVM) wafer fab will be reviewed. Finally future directions of the investigation will be discussed.

  10. Overlay considerations for 300-mm lithography

    Science.gov (United States)

    Mono, Tobias; Schroeder, Uwe P.; Nees, Dieter; Palitzsch, Katrin; Koestler, Wolfram; Bruch, Jens; Kramp, Sirko; Veldkamp, Markus; Schuster, Ralf

    2003-05-01

    Generally, the potential impact of systematical overlay errors on 300mm wafers is much larger than on 200mm wafers. Process problems which are merely identified as minor edge yield detractors on 200mm wafers, can evolve as major roadblocks for 300mm lithography. Therefore, it is commonly believed that achieving product overlay specifications on 300mm wafers is much more difficult than on 200mm wafers. Based on recent results on high volume 300mm DRAM manufacturing, it is shown that in reality this assumption does not hold. By optimizing the process, overlay results can be achieved which are comparable to the 200mm reference process. However, the influence of non-lithographic processes on the overlay performance becomes much more critical. Based on examples for specific overlay signatures, the influence of several processes on the overlay characteristics of 300mm wafers is demonstrated. Thus, process setup and process changes need to be analyzed monitored much more carefully. Any process variations affecting wafer related overlay have to be observed carefully. Fast reaction times are critical to avoid major yield loss. As the semiconductor industry converts to 300mm technology, lithographers have to focus more than ever on process integration aspects.

  11. The effect of individually-induced processes on image-based overlay and diffraction-based overlay

    Science.gov (United States)

    Oh, SeungHwa; Lee, Jeongjin; Lee, Seungyoon; Hwang, Chan; Choi, Gilheyun; Kang, Ho-Kyu; Jung, EunSeung

    2014-04-01

    In this paper, set of wafers with separated processes was prepared and overlay measurement result was compared in two methods; IBO and DBO. Based on the experimental result, theoretical approach of relationship between overlay mark deformation and overlay variation is presented. Moreover, overlay reading simulation was used in verification and prediction of overlay variation due to deformation of overlay mark caused by induced processes. Through this study, understanding of individual process effects on overlay measurement error is given. Additionally, guideline of selecting proper overlay measurement scheme for specific layer is presented.

  12. Diffraction based overlay re-assessed

    Science.gov (United States)

    Leray, Philippe; Laidler, David; D'havé, Koen; Cheng, Shaunee

    2011-03-01

    In recent years, numerous authors have reported the advantages of Diffraction Based Overlay (DBO) over Image Based Overlay (IBO), mainly by comparison of metrology figures of merit such as TIS and TMU. Some have even gone as far as to say that DBO is the only viable overlay metrology technique for advanced technology nodes; 22nm and beyond. Typically the only reported drawback of DBO is the size of the required targets. This severely limits its effective use, when all critical layers of a product, including double patterned layers need to be measured, and in-die overlay measurements are required. In this paper we ask whether target size is the only limitation to the adoption of DBO for overlay characterization and control, or are there other metrics, which need to be considered. For example, overlay accuracy with respect to scanner baseline or on-product process overlay control? In this work, we critically re-assess the strengths and weaknesses of DBO for the applications of scanner baseline and on-product process layer overlay control. A comprehensive comparison is made to IBO. For on product process layer control we compare the performance on critical process layers; Gate, Contact and Metal. In particularly we focus on the response of the scanner to the corrections determined by each metrology technique for each process layer, as a measure of the accuracy. Our results show that to characterize an overlay metrology technique that is suitable for use in advanced technology nodes requires much more than just evaluating the conventional metrology metrics of TIS and TMU.

  13. Amenability of Muzret bituminous coal to oil agglomeration

    Energy Technology Data Exchange (ETDEWEB)

    Sahinoglu, E.; Uslu, T. [Karadeniz Technical University, Department of Mining Engineering, 61080 Trabzon (Turkey)

    2008-12-15

    Laboratory scale agglomeration tests were undertaken to investigate the amenability of Muzret (Yusufeli-Artvin) bituminous coal to oil agglomeration. Kerosene was extensively used as oil in the tests. In addition, fuel oil, diesel oil, and hazelnut oil were also used in order to determine the effect of oil type. The effects of the parameters including coal content, kerosene content, agglomeration time, coal particle size, pH, oil type, and agitation rate, on the combustible matter recovery, ash reduction and pyritic sulphur reduction, were investigated. It was found that Muzret bituminous coal could be readily cleaned by oil agglomeration with substantial reductions in ash and pyritic sulphur content. Maximum combustible matter recovery, ash reduction and pyritic sulphur reduction were achieved to be 85.54%, 59.98%, and 85.17%, respectively. (author)

  14. Co-pyrolysis characteristic of biomass and bituminous coal.

    Science.gov (United States)

    Li, Shuaidan; Chen, Xueli; Liu, Aibin; Wang, Li; Yu, Guangsuo

    2015-03-01

    Co-pyrolysis characteristics of biomass and bituminous coal have been studied in this work. The temperature was up to 900°C with the heating rates of 10, 15, 20, 25 and 30°C/min. Rice straw, saw dust, microcrystalline cellulose, lignin and Shenfu bituminous coal were chosen as samples. Six different biomass ratios were used. The individual thermal behavior of each sample was obtained. The experimental weight fractions of the blended samples and the calculated values were compared. The results show that the weight fractions of the blended samples behave differently with calculated ones during the co-pyrolysis process. With the increasing biomass ratio, relative deviations between experimental weight fractions and calculated ones are larger. H/C molar ratio, heat transfer properties of biomass would affect to the interaction between biomass and coal. The maximum degradation rates are slower than the calculated ones. The activation energy distributions also changed by adding some biomass into coal.

  15. Performance of PAHs emission from bituminous coal combustion

    Institute of Scientific and Technical Information of China (English)

    严建华; 尤孝方; 李晓东; 倪明江; 尹雪峰; 岑可法

    2004-01-01

    Carcinogenic and mutagenic polycyclic aromatic hydrocarbons (PAHs) generated in coal combustion have caused great environmental health concern. Seventeen PAHs (16 high priority PAHs recommended by USEPA plus Benzo[e]pyrene) present in five raw bituminous coals and released during bituminous coal combustion were studied. The effects of combustion temperature, gas atmosphere, and chlorine content of raw coal on PAHs formation were investigated. Two additives (copper and cupric oxide) were added when the coal was burned. The results indicated that significant quantities of PAHs were produced from incomplete combustion of coal pyrolysis products at high temperature, and that temperature is an important causative factor of PAHs formation. PAHs concentrations decrease with the increase of chlorine content in oxygen or in nitrogen atmosphere. Copper and cupric oxide additives can promote PAHs formation (especially the multi-ring PAHs) during coal combustion.

  16. Qmerit-calibrated overlay to improve overlay accuracy and device performance

    Science.gov (United States)

    Ullah, Md Zakir; Jazim, Mohamed Fazly Mohamed; Sim, Stella; Lim, Alan; Hiem, Biow; Chuen, Lieu Chia; Ang, Jesline; Lim, Ek Chow; Klein, Dana; Amit, Eran; Volkovitch, Roie; Tien, David; Choi, DongSub

    2015-03-01

    In advanced semiconductor industries, the overlay error budget is getting tighter due to shrinkage in technology. To fulfill the tighter overlay requirements, gaining every nanometer of improved overlay is very important in order to accelerate yield in high-volume manufacturing (HVM) fabs. To meet the stringent overlay requirements and to overcome other unforeseen situations, it is becoming critical to eliminate the smallest imperfections in the metrology targets used for overlay metrology. For standard cases, the overlay metrology recipe is selected based on total measurement uncertainty (TMU). However, under certain circumstances, inaccuracy due to target imperfections can become the dominant contributor to the metrology uncertainty and cannot be detected and quantified by the standard TMU. For optical-based overlay (OBO) metrology targets, mark asymmetry is a common issue which can cause measurement inaccuracy, and it is not captured by standard TMU. In this paper, a new calibration method, Archer Self-Calibration (ASC), has been established successfully in HVM fabs to improve overlay accuracy on image-based overlay (IBO) metrology targets. Additionally, a new color selection methodology has been developed for the overlay metrology recipe as part of this calibration method. In this study, Qmerit-calibrated data has been used for run-to-run control loop at multiple devices. This study shows that color filter can be chosen more precisely with the help of Qmerit data. Overlay stability improved by 10~20% with best color selection, without causing any negative impact to the products. Residual error, as well as overlay mean plus 3-sigma, showed an improvement of up to 20% when Qmerit-calibrated data was used. A 30% improvement was seen in certain electrical data associated with tested process layers.

  17. Polishing Your Transparencies: Mounting, Masking, Overlays.

    Science.gov (United States)

    Jobe, Holly; Cannon, Glenn

    This brief guide discusses the mounting of overhead transparencies on frames, the types of mounts, the proper masking for presentation, and the use of overlays. Numerous line drawings provide the reader with a helpful visual reference. (RAO)

  18. Steam and air plasma gasification of bituminous coal and petrocoke

    OpenAIRE

    Vladimir Messerle; Alexander Ustimenko

    2012-01-01

    This paper presents a numerical analysis and experimental investigation of two very different solid fuels, low-rank bituminous coal of 40 % ash content and petrocoke of 3 % ash content, gasification under steam and air plasma conditions with an aim of producing synthesis gas. Numerical analysis was fulfilled using the software package TERRA for equilibrium computation. Using the results of the numerical simulation, experiments on plasma steam gasification of the petrocoke and air and steam ga...

  19. Diffraction based overlay and image based overlay on production flow for advanced technology node

    Science.gov (United States)

    Blancquaert, Yoann; Dezauzier, Christophe

    2013-04-01

    One of the main challenges for lithography step is the overlay control. For the advanced technology node like 28nm and 14nm, the overlay budget becomes very tight. Two overlay techniques compete in our advanced semiconductor manufacturing: the Diffraction based Overlay (DBO) with the YieldStar S200 (ASML) and the Image Based Overlay (IBO) with ARCHER (KLA). In this paper we will compare these two methods through 3 critical production layers: Poly Gate, Contact and first metal layer. We will show the overlay results of the 2 techniques, explore the accuracy and compare the total measurement uncertainty (TMU) for the standard overlay targets of both techniques. We will see also the response and impact for the Image Based Overlay and Diffraction Based Overlay techniques through a process change like an additional Hardmask TEOS layer on the front-end stack. The importance of the target design is approached; we will propose more adapted design for image based targets. Finally we will present embedded targets in the 14 FDSOI with first results.

  20. A moving overlay shrinks the attentional blink.

    Science.gov (United States)

    Chua, Fook K

    2015-01-01

    This report describes a study examining the effects of overlaying a veil of spots on the letters in a central rapid serial visual presentation stream. Observers identified two target letters (T1 and T2, respectively) embedded in a stream of distractor letters printed in a different color. In Experiment 1, the attentional blink (AB) diminished when a different overlay veiled each letter, such that the spots appeared to move as the letters changed. Experiment 2 concerned whether the performance enhancement occurred because the overlay hampered processing of the lag 1 distractor, thus weakening the distractor's interference with T1. Experiment 3 focused on how changing the overlay at or around T1 affected the AB. The attention disengagement hypothesis was proposed to explain the common theme in the results-that performance was only enhanced when different overlays were applied to the T1 and lag 1 frames. The claim is that the AB reflects a failure of prompt attentional disengagement from T1, which, in turn, delays reengagement when T2 appears shortly thereafter. When T1's disappearance is accompanied by an overlay change, the perceptual system gets an additional cue signaling that the visual scene has changed, thereby inducing attentional disengagement. Apart from facilitating prompt reengagement at the next target, earlier disengagement also improves target recovery by excluding features of the trailing item, likely to be a distractor, from working memory.

  1. Correlation-aware multimedia content distribution in overlay networks

    Science.gov (United States)

    Zhu, Ying; Li, Baochun

    2006-01-01

    We address the question: What is the best way to construct a mesh overlay topology for multimedia content distribution, such that the highest streaming rate can be achieved? We model overlay capacity correlations as linear capacity constraints (LCC) and propose a distributed algorithm that constructs an overlay mesh which incorporates heuristically inferred linear capacity constraints. Our simulations results confirm the accuracy of representing overlays using our LCC model and show the LCC-overlay achieving substantial improvement in achievable flow rate.

  2. Enhacement of intrafield overlay using a design based metrology system

    Science.gov (United States)

    Jo, Gyoyeon; Ji, Sunkeun; Kim, Shinyoung; Kang, Hyunwoo; Park, Minwoo; Kim, Sangwoo; Kim, Jungchan; Park, Chanha; Yang, Hyunjo; Maruyama, Kotaro; Park, Byungjun

    2016-03-01

    As the scales of the semiconductor devices continue to shrink, accurate measurement and control of the overlay have been emphasized for securing more overlay margin. Conventional overlay analysis methods are based on the optical measurement of the overlay mark. However, the overlay data obtained from these optical methods cannot represent the exact misregistration between two layers at the circuit level. The overlay mismatch may arise from the size or pitch difference between the overlay mark and the real pattern. Pattern distortion, caused by CMP or etching, could be a source of the overlay mismatch as well. Another issue is the overlay variation in the real circuit pattern which varies depending on its location. The optical overlay measurement methods, such as IBO and DBO that use overlay mark on the scribeline, are not capable of defining the exact overlay values of the real circuit. Therefore, the overlay values of the real circuit need to be extracted to integrate the semiconductor device properly. The circuit level overlay measurement using CDSEM is time-consuming in extracting enough data to indicate overall trend of the chip. However DBM tool is able to derive sufficient data to display overlay tendency of the real circuit region with high repeatability. An E-beam based DBM(Design Based Metrology) tool can be an alternative overlay measurement method. In this paper, we are going to certify that the overlay values extracted from optical measurement cannot represent the circuit level overlay values. We will also demonstrate the possibility to correct misregistration between two layers using the overlay data obtained from the DBM system.

  3. Robotic weld overlay coatings for erosion control

    Science.gov (United States)

    The erosion of materials by the impact of solid particles has received increasing attention during the past twenty years. Recently, research has been initiated with the event of advanced coal conversion processes in which erosion plays an important role. The resulting damage, termed Solid Particle Erosion (SPE), is of concern primarily because of the significantly increased operating costs which result in material failures. Reduced power plant efficiency due to solid particle erosion of boiler tubes and waterfalls has led to various methods to combat SPE. One method is to apply coatings to the components subjected to erosive environments. Protective weld overlay coatings are particularly advantageous in terms of coating quality. The weld overlay coatings are essentially immune to spallation due to a strong metallurgical bond with the substrate material. By using powder mixtures, multiple alloys can be mixed in order to achieve the best performance in an erosive environment. However, a review of the literature revealed a lack of information on weld overlay coating performance in erosive environments which makes the selection of weld overlay alloys a difficult task. The objective of this project is to determine the effects of weld overlay coating composition and microstructure on erosion resistance. These results will lead to a better understanding of erosion mitigation in CFB's.

  4. Exploring overlay journals: the RIOJA project

    CERN Document Server

    CERN. Geneva

    2007-01-01

    Researchers in cosmology and astrophysics depend on the arXiv repository for the registration and dissemination of their work, as well as for current awareness, yet they continue to submit papers to journals for review. Could rapid quality certification be overlaid directly onto the arXiv repository? This presentation introduces the RIOJA (Repository Interface to Overlaid Journal Archives) project, on which a group of cosmology researchers from the UK is working with UCL Library Services and Cornell University. The project is creating a tool to support the overlay of journals onto repositories, and will demonstrate a cosmology journal overlaid on top of arXiv. RIOJA will also work with the cosmology community to explore the social and economic aspects of journal overlay in this discipline: what other value, besides the quality stamp, does journal publication typically add? What are the costs of the ideal overlay journal for this community, and how could those costs be recovered? Would researchers real...

  5. Patent Overlay Mapping: Visualizing Technological Distance

    CERN Document Server

    Kay, Luciano; Youtie, Jan; Porter, Alan L; Rafols, Ismael

    2012-01-01

    The purpose of this paper is to present a new global patent map that represents all technological categories, and a method to locate patent data of individual organizations and technological fields on the global map. This second patent overlay map technique is shown to be of potential interest to support competitive intelligence and policy decision-making. The global patent map is based on similarities in citing-to-cited relationships between categories of the International Patent Classification (IPC) of European Patent Office (EPO) patents from 2000 to 2006. This patent dataset, extracted from PatStat database, represents more than 760,000 patent records in more than 400 IPC categories. To illustrate the kind of analytical support offered by this approach, the paper shows the overlay of nanotechnology-related patenting activities of two companies and two different nanotechnology subfields on to the global patent map. The exercise shows the potential of patent overlay maps to visualize technological areas and...

  6. Overlay Technique for Transcatheter Left Atrial Appendage Closure.

    Science.gov (United States)

    Li, Shuang; Zhu, Mengyun; Lu, Yunlan; Tang, Kai; Zhao, Dongdong; Chen, Wei; Xu, Yawei

    2015-08-01

    The Overlay technique is popular in peripheral artery interventions, but not in coronary or cardiac structural procedures. We present an initial experience using three-episode overlays during a transcatheter left atrial appendage closure. The first overlay was applied to facilitate advancement of the delivery sheath into left atrium. The second overlay was used to navigate the advancement of prepped delivery system containing the compressed occluder into its optimal position in the left atrium. The third overlay facilitated the real-time deployment of the closure device. This case report demonstrates the effectiveness of the overlay technique in facilitating each step of the transcatheter left atrial appendage closure.

  7. KML Super Overlay to WMS Translator

    Science.gov (United States)

    Plesea, Lucian

    2007-01-01

    This translator is a server-based application that automatically generates KML super overlay configuration files required by Google Earth for map data access via the Open Geospatial Consortium WMS (Web Map Service) standard. The translator uses a set of URL parameters that mirror the WMS parameters as much as possible, and it also can generate a super overlay subdivision of any given area that is only loaded when needed, enabling very large areas of coverage at very high resolutions. It can make almost any dataset available as a WMS service visible and usable in any KML application, without the need to reformat the data.

  8. Hybrid overlay metrology for high order correction by using CDSEM

    Science.gov (United States)

    Leray, Philippe; Halder, Sandip; Lorusso, Gian; Baudemprez, Bart; Inoue, Osamu; Okagawa, Yutaka

    2016-03-01

    Overlay control has become one of the most critical issues for semiconductor manufacturing. Advanced lithographic scanners use high-order corrections or correction per exposure to reduce the residual overlay. It is not enough in traditional feedback of overlay measurement by using ADI wafer because overlay error depends on other process (etching process and film stress, etc.). It needs high accuracy overlay measurement by using AEI wafer. WIS (Wafer Induced Shift) is the main issue for optical overlay, IBO (Image Based Overlay) and DBO (Diffraction Based Overlay). We design dedicated SEM overlay targets for dual damascene process of N10 by i-ArF multi-patterning. The pattern is same as device-pattern locally. Optical overlay tools select segmented pattern to reduce the WIS. However segmentation has limit, especially the via-pattern, for keeping the sensitivity and accuracy. We evaluate difference between the viapattern and relaxed pitch gratings which are similar to optical overlay target at AEI. CDSEM can estimate asymmetry property of target from image of pattern edge. CDSEM can estimate asymmetry property of target from image of pattern edge. We will compare full map of SEM overlay to full map of optical overlay for high order correction ( correctables and residual fingerprints).

  9. Concentration of viruses from water on bituminous coal

    Energy Technology Data Exchange (ETDEWEB)

    Lakhe, S.B.; Parhad, N.M.

    1988-05-01

    The potential of bituminous coal for adsorption of viruses, using poliovirus as a model, was investigated. Influence of pH of water on the adsorption of viruses on a coal bed with and without addition of cation (Al/sup 3 +/) indicated that poliovirus could be adsorbed efficiently at pH 5 in presence of AlCl/sub 3/ at a concentration of 0.0005 M. studies on the effect of different concentrations of monovalent, divalent and trivalent cations showed that the trivalent cation was more effective and was required at a lower concentration than other cations tested. A coal bed of 1.5 g could adsorb as high as 204,000 PFU from water based on the absence of virus in the filtrate. Total organic carbon content of the water did not interfere in virus adsorption to coal. The results obtained indicated that a bituminous coal bed could be used as one of the methods for efficient concentration of viruses from water. 31 refs., 8 tabs.

  10. Colors, colored overlays, and reading skills

    Directory of Open Access Journals (Sweden)

    Arcangelo eUccula

    2014-07-01

    Full Text Available In this article, we are concerned with the role of colors in reading written texts. It has been argued that colored overlays applied above written texts positively influence both reading fluency and reading speed. These effects would be particularly evident for those individuals affected by the so called Meares-Irlen syndrome, i.e. who experience eyestrain and/or visual distortions – e.g. color, shape or movement illusions – while reading. This condition would interest the 12-14% of the general population and up to the 46% of the dyslexic population. Thus, colored overlays have been largely employed as a remedy for some aspects of the difficulties in reading experienced by dyslexic individuals, as fluency and speed. Despite the wide use of colored overlays, how they exert their effects has not been made clear yet. Also, according to some researchers, the results supporting the efficacy of colored overlays as a tool for helping readers are at least controversial. Furthermore, the very nature of the Meares-Irlen syndrome has been questioned. Here we provide a concise, critical review of the literature.

  11. Physical expander in Virtual Tree Overlay

    CERN Document Server

    Izumi, Taisuke; Valero, Mathieu

    2011-01-01

    In this paper, we propose a new construction of constantdegree expanders motivated by their application in P2P overlay networks and in particular in the design of robust trees overlay. Our key result can be stated as follows. Consider a complete binary tree T and construct a random pairing {\\Pi} between leaf nodes and internal nodes. We prove that the graph G\\Pi obtained from T by contracting all pairs (leaf-internal nodes) achieves a constant node expansion with high probability. The use of our result in improving the robustness of tree overlays is straightforward. That is, if each physical node participating to the overlay manages a random pair that couples one virtual internal node and one virtual leaf node then the physical-node layer exhibits a constant expansion with high probability. We encompass the difficulty of obtaining this random tree virtualization by proposing a local, selforganizing and churn resilient uniformly-random pairing algorithm with O(log2 n) running time. Our algorithm has the merit ...

  12. Large dynamic range Atomic Force Microscope for overlay improvements

    NARCIS (Netherlands)

    Kuiper, S.; Fritz, E.C.; Crowcombe, W.E.; Liebig, T.; Kramer, G.F.I.; Witvoet, G.; Duivenvoorde, T.; Overtoom, A.J.; Rijnbeek, R.A.; Zwet, E.J. van; Dijsseldonk, A. van; Boef, A. den; Beems, M.; Levasier, L.

    2016-01-01

    Nowadays most overlay metrology tools assess the overlay performance based on marker features which are deposited next to the functional device features within each layer of the semiconductor device. However, correct overlay of the relatively coarse marker features does not directly guarantee correc

  13. Network-aware SuperPeers-Peers Geometric Overlay Network

    NARCIS (Netherlands)

    Lua, E.K.; Zhou, X.

    2007-01-01

    Peer-to-Peer (P2P) overlay networks can be utilized to deploy massive Internet overlay services such as multicast, content distribution, file sharing, etc. efficiently without any underlying network support. The crucial step to meet this objective is to design network-aware overlay network topologie

  14. Leaching tests of simulated Cogema bituminized waste form

    Energy Technology Data Exchange (ETDEWEB)

    Nakayama, S.; Akimoto, T.; Iida, Y.; Nagano, T. [Japan Atomic Energy Research Institute, Tokai, Ibaraki (Japan)

    2000-07-01

    The leaching behavior of COGEMA-type bituminized radioactive waste was studied for the atmospheric and anaerobic conditions. Active and inactive laboratory-scale bitumen samples, including two major salts of NaNO{sub 3} and BaSO{sub 4}, were contacted with deionized water, an alkaline solution (0.01 mol/L Ca(OH){sub 2} or 0.03 mol/L KOH), or a saline solution (0.5 mol/L KCl). It was found that the release of salt was reduced in the Ca(OH){sub 2} solution compared with deionized water under the atmospheric conditions. No significant difference in the concentrations of {sup 237}Np in leachants contacted with the samples for 7 days was observed between the atmospheric and the anaerobic conditions. (authors)

  15. Steam and air plasma gasification of bituminous coal and petrocoke

    Directory of Open Access Journals (Sweden)

    Vladimir Messerle

    2012-12-01

    Full Text Available This paper presents a numerical analysis and experimental investigation of two very different solid fuels, low-rank bituminous coal of 40 % ash content and petrocoke of 3 % ash content, gasification under steam and air plasma conditions with an aim of producing synthesis gas. Numerical analysis was fulfilled using the software package TERRA for equilibrium computation. Using the results of the numerical simulation, experiments on plasma steam gasification of the petrocoke and air and steam gasification of the coal were conducted in an original installation. Nominal power of the plasma installation is 100 kWe and sum consumption of the reagents is up to 20 kg/h. High quality synthesis gas was produced in the experiments on solid fuels plasma gasification. It has been found that the synthesis gas content at about 97.4 vol.% can be produced. Comparison between the numerical and experimental results showed satisfactory agreement. 

  16. CO Chemisorption at Metal Surfaces and Overlayers

    DEFF Research Database (Denmark)

    Hammer, Bjørk; Morikawa, Y.; Nørskov, Jens Kehlet

    1996-01-01

    A database of ab initio calculations of the chemisorption energy of CO over Ni(111), Cu(111), Ru(0001), Pd(111), Ag(111), Pt(111), Au(111), Cu3Pt(111), and some metallic overlayer structures is presented. The trends can be reproduced with a simple model describing the interaction between the meta...... d states and the CO 2 pi* and 5 sigma states, renormalized by the metal sp continuum. Our model rationalizes the results by Rodriguez and Goodman [Science 257, 897 (1992)] showing a strong correlation between the CO chemisorption energy and the surface core level shift.......A database of ab initio calculations of the chemisorption energy of CO over Ni(111), Cu(111), Ru(0001), Pd(111), Ag(111), Pt(111), Au(111), Cu3Pt(111), and some metallic overlayer structures is presented. The trends can be reproduced with a simple model describing the interaction between the metal...

  17. Investigation of the combustion characteristics of Zonguldak bituminous coal using DTA and DTG

    Energy Technology Data Exchange (ETDEWEB)

    Haykiri-Acma, H.; Yaman, S.; Kucukbayrak, S.; Okutan, H. [Istanbul Technical University, Istanbul (Turkey). Dept. of Chemical Engineering

    2006-06-21

    Combustion characteristics of coking, semicoking, and noncoking Turkish bituminous coal samples from Zonguldak basin were investigated applying differential thermal analysis (DTA) and differential thermogravimetry (DTG) techniques. Results were compared with that of the coke from Zonguldak bituminous coal, a Turkish lignite sample from Soma, and a Siberian bituminous coal sample. The thermal data from both techniques showed some differences depending on the proximate analyses of the samples. Noncombustible components of the volatile matter led to important changes in thermal behavior. The data front both methods were, evaluated jointly, and some thermal properties were interpreted considering these methods in a complementary combination.

  18. Achieving optimum diffraction based overlay performance

    Science.gov (United States)

    Leray, Philippe; Laidler, David; Cheng, Shaunee; Coogans, Martyn; Fuchs, Andreas; Ponomarenko, Mariya; van der Schaar, Maurits; Vanoppen, Peter

    2010-03-01

    Diffraction Based Overlay (DBO) metrology has been shown to have significantly reduced Total Measurement Uncertainty (TMU) compared to Image Based Overlay (IBO), primarily due to having no measurable Tool Induced Shift (TIS). However, the advantages of having no measurable TIS can be outweighed by increased susceptibility to WIS (Wafer Induced Shift) caused by target damage, process non-uniformities and variations. The path to optimum DBO performance lies in having well characterized metrology targets, which are insensitive to process non-uniformities and variations, in combination with optimized recipes which take advantage of advanced DBO designs. In this work we examine the impact of different degrees of process non-uniformity and target damage on DBO measurement gratings and study their impact on overlay measurement accuracy and precision. Multiple wavelength and dual polarization scatterometry are used to characterize the DBO design performance over the range of process variation. In conclusion, we describe the robustness of DBO metrology to target damage and show how to exploit the measurement capability of a multiple wavelength, dual polarization scatterometry tool to ensure the required measurement accuracy for current and future technology nodes.

  19. Facilitating Service Discovery with Semantic Overlay

    Institute of Scientific and Technical Information of China (English)

    Hai Jin; Hao Wu; Xiao-Min Ning

    2006-01-01

    Service Oriented Architecture (SOA) and Peer-to-Peer (P2P) computing share many common characteristics.It is believed that the combination of the two emerging techniques is a very promising method in promoting the web services (WS). Because the service discovery plays a key role in the integration, here a P2P-based framework to manage the knowledge of service and locating services is proposed. In this paper, the details of the principle, constructing and maintaining of service semantic overlay architecture have been described, and the way how the semantic overlay facilitates discovery of service resources is illustrated. To enable the semantic web service superiority, Service Ontology, which is considered as the service semantic model, is employed to depict service. The service discovery includes two phases: searching on the service semantic overlay; and local discovery in peer's service repository. Various solutions have been proposed to realize those two phases.Furthermore, tests are carried out to evaluate service discovery on the architecture.

  20. Overlay Spectrum Sharing using Improper Gaussian Signaling

    KAUST Repository

    Amin, Osama

    2016-11-30

    Improper Gaussian signaling (IGS) scheme has been recently shown to provide performance improvements in interference limited networks as opposed to the conventional proper Gaussian signaling (PGS) scheme. In this paper, we implement the IGS scheme in overlay cognitive radio system, where the secondary transmitter broadcasts a mixture of two different signals. The first signal is selected from the PGS scheme to match the primary message transmission. On the other hand, the second signal is chosen to be from the IGS scheme in order to reduce the interference effect on the primary receiver. We then optimally design the overlay cognitive radio to maximize the secondary link achievable rate while satisfying the primary network quality of service requirements. In particular, we consider full and partial channel knowledge scenarios and derive the feasibility conditions of operating the overlay cognitive radio systems. Moreover, we derive the superiority conditions of the IGS schemes over the PGS schemes supported with closed form expressions for the corresponding power distribution and the circularity coefficient and parameters. Simulation results are provided to support our theoretical derivations.

  1. SEM based overlay measurement between resist and buried patterns

    Science.gov (United States)

    Inoue, Osamu; Okagawa, Yutaka; Hasumi, Kazuhisa; Shao, Chuanyu; Leray, Philippe; Lorusso, Gian; Baudemprez, Bart

    2016-03-01

    With the continuous shrink in pattern size and increased density, overlay control has become one of the most critical issues in semiconductor manufacturing. Recently, SEM based overlay of AEI (After Etch Inspection) wafer has been used for reference and optimization of optical overlay (both Image Based Overlay (IBO) and Diffraction Based Overlay (DBO)). Overlay measurement at AEI stage contributes monitor and forecast the yield after formation by etch and calibrate optical measurement tools. however those overlay value seems difficult directly for feedback to a scanner. Therefore, there is a clear need to have SEM based overlay measurements of ADI (After Develop Inspection) wafers in order to serve as reference for optical overlay and make necessary corrections before wafers go to etch. Furthermore, to make the corrections as accurate as possible, actual device like feature dimensions need to be measured post ADI. This device size measurement is very unique feature of CDSEM , which can be measured with smaller area. This is currently possible only with the CD-SEM. This device size measurement is very unique feature of CD-SEM , which can be measured with smaller area. In this study, we assess SEM based overlay measurement of ADI and AEI wafer by using a sample from an N10 process flow. First, we demonstrate SEM based overlay performance at AEI by using dual damascene process for Via 0 (V0) and metal 1 (M1) layer. We also discuss the overlay measurements between litho-etch-litho stages of a triple patterned M1 layer and double pattern V0. Second, to illustrate the complexities in image acquisition and measurement we will measure overlay between M1B resist and buried M1A-Hard mask trench. Finally, we will show how high accelerating voltage can detect buried pattern information by BSE (Back Scattering Electron). In this paper we discuss the merits of this method versus standard optical metrology based corrections.

  2. State of the art report on bituminized waste forms of radioactive wastes

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Tae Kook; Shon, Jong Sik; Kim, Kil Jeong; Lee, Kang Moo; Jung, In Ha

    1998-03-01

    In this report, research and development results on the bituminization of radioactive wastes are closely reviewed, especially those regarding waste treatment technologies, waste solidifying procedures and the characteristics of asphalt and solidified forms. A new concept of the bituminization method is suggested in this report which can improve the characteristics of solidified forms. Stable solid forms with high leach resistance, high thermal resistance and good compression strength were produced by the suggested bituminization method, in which spent polyethylene from agricultural farms was added. This report can help further research and development of improved bituminized forms of radioactive wastes that will maintain long term stabilities in disposal sites. (author). 59 refs., 19 tabs., 18 figs

  3. Influence of association of "EVA-NBR" on indirect tensile strength of modified bituminous concrete

    Science.gov (United States)

    Chinoun, M.; Soudani, K.; Haddadi, S.

    2016-04-01

    The aim of this work is to contribute to the improvement of the mechanical properties of bituminous concrete by modification of bituminous concrete. In this study, we present the results of the indirect tensile strength "ITS" of modified bituminous concrete by the combination of two modifiers, one is a plastomer EVA (Ethylene Vinyl Acetate) and the other is a industrial waste from the shoe soles grinding NBR (Nitrile Butadiene Rubber) as crumb rubber. To modify the bitumen a wet process was used. The results show that the modification of bitumen by EVA-NBR combination increases their resistance to the indirect traction "ITS" compared to the bituminous concrete control. The mixture of 5% [50% EVA+ 50% NBR] is given the best result among the other associations.

  4. Life extension of boilers using weld overlay protection

    Energy Technology Data Exchange (ETDEWEB)

    Lai, G.; Hulsizer, P. [Welding Services Inc., Norcross, GA (United States); Brooks, R. [Welding Services Inc., Welding Services Europe, Spijkenisse (Netherlands)

    1998-12-31

    The presentation describes the status of modern weld overlay technology for refurbishment, upgrading and life extension of boilers. The approaches to life extension of boilers include field overlay application, shop-fabricated panels for replacement of the worn, corroded waterwall and shop-fabricated overlay tubing for replacement of individual tubes in superheaters, generating banks and other areas. The characteristics of weld overlay products are briefly described. Also discussed are successful applications of various corrosion-resistant overlays for life extension of boiler tubes in waste-to-energy boilers, coal-fired boilers and chemical recovery boilers. Types of corrosion and selection of weld overlay alloys in these systems are also discussed. (orig.) 14 refs.

  5. Topology-aware Overlay Multicast over IP Multicast Networks

    Institute of Scientific and Technical Information of China (English)

    CHEN Xiao; SHAO Hua-gang; WANG Wei-nong

    2008-01-01

    Most existing overlay multicast approaches refuse to consider any network layer support no matter whether it is available or not. This design principle greatly increases the complexity of the routing algorithms and makes the overlay topologies incompatible with the underlying network. To address these issues, topology-aware overlay multicast over IP multicast networks (TOMIMN) was proposed as a novel overlay multicast protocol, which exploits the cooperation between end-hosts and IP multicast routers to construct a topology-aware overlay tree. Through a little modification to protocol independent multicast sparse mode (PIM-SM),a multicast router is able to receive registration from nearby group members and redirect passing-by join re-quests to them. Due to the multicast router's support, TOMIMN organizes its group members into an overlay multicast tree efficiently, which matches the physical network topology well.

  6. Layout optimization for multilayer overlay targets

    Science.gov (United States)

    Binns, L. A.; Smith, N. P.; Ausschnitt, C. P.; Morningstar, J.; Muth, W.; Schneider, J.; Yerdon, R.

    2006-03-01

    A novel overlay target developed by IBM and Accent Optical Technologies, Blossom, allows simultaneous overlay measurements of multiple layers (currently, up to 28) with a single target. This is achieved by a rotationally symmetric arrangement of small (4 micron) targets in a 50 micron square area, described more fully in a separate paper. In this paper, we examine the lessons learned in developing and testing the Blossom design. We start by examining proximity effects; the spacing of adjacent targets means that both the precision-like Total Measurement Uncertainty (TMU) and accuracy of a measurement can be affected by proximity of features. We use a mixture of real and modelled data to illustrate this problem, and find that the layout of Blossom reduces the proximity-induced bias. However, we do find that in certain cases proximity effects can increase the TMU of a particular measurement. The solution is to ensure that parts of the target that interact detrimentally are maximally separated. We present a solution to this, viewing the problem as a constrained Travelling Salesman Problem. We have imposed some global constraints, for example printing front-end and back-end layers on separate targets, and consistency with the overlay measurement strategy. Initially, we assume that pairwise measurements are either critical or non-critical, and optimize the layout so that the critical layers are both not placed adjacent to any prior or intermediate-layer features. We then build upon this structure, to consider the effect of low-energy implants (that cannot be seen once processed) and site re-use possibilities. Beyond this, we also investigate the impact of more strategic optimizations, for example, tuning the number of features on each layer. In each case, we present on-product performance data achieved, and modelled data on some additional target variants / extreme cases.

  7. Molecular Dynamics study of Pb overlayer on Cu(100)

    Science.gov (United States)

    Karimi, M.; Tibbits, P.; Ila, D.; Dalins, I.; Vidali, G.

    1991-01-01

    Isothermal-isobaric Molecular Dynamics (MD) simulation of a submonolayer Pb film in c(2x2) ordered structure adsorbed on a Cu(100) substrate showed retention of order to high T. The Embedded Atom Method (EAM) calculated the energy of atoms of overlayer and substrate. The time-averaged squared modulus of the two dimensional structure factor for the Pb overlayer measured the order of the overlayer. The results are for increasing T only, and require verification by simulated cooling.

  8. Assessment of a Cambridge Structural Database-driven overlay program.

    Science.gov (United States)

    Giangreco, Ilenia; Olsson, Tjelvar S G; Cole, Jason C; Packer, Martin J

    2014-11-24

    We recently published an improved methodology for overlaying multiple flexible ligands and an extensive data set for validating pharmacophore programs. Here, we combine these two developments and present evidence of the effectiveness of the new overlay methodology at predicting correct superimpositions for systems with varying levels of complexity. The overlay program was able to generate correct predictions for 95%, 73%, and 39% of systems classified as easy, moderate, and hard, respectively.

  9. Gasification of high ash, high ash fusion temperature bituminous coals

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Guohai; Vimalchand, Pannalal; Peng, WanWang

    2015-11-13

    This invention relates to gasification of high ash bituminous coals that have high ash fusion temperatures. The ash content can be in 15 to 45 weight percent range and ash fusion temperatures can be in 1150.degree. C. to 1500.degree. C. range as well as in excess of 1500.degree. C. In a preferred embodiment, such coals are dealt with a two stage gasification process--a relatively low temperature primary gasification step in a circulating fluidized bed transport gasifier followed by a high temperature partial oxidation step of residual char carbon and small quantities of tar. The system to process such coals further includes an internally circulating fluidized bed to effectively cool the high temperature syngas with the aid of an inert media and without the syngas contacting the heat transfer surfaces. A cyclone downstream of the syngas cooler, operating at relatively low temperatures, effectively reduces loading to a dust filtration unit. Nearly dust- and tar-free syngas for chemicals production or power generation and with over 90%, and preferably over about 98%, overall carbon conversion can be achieved with the preferred process, apparatus and methods outlined in this invention.

  10. Reactivity and characterisation of various rank Turkish bituminous coal chars

    Energy Technology Data Exchange (ETDEWEB)

    Kizgut, S.; Baran, Y.; Cuhadaroglu, D. [Karaelmas University, Zonguldak (Turkey). Faculty of Engineering

    2003-07-01

    A set of seven bituminous coal chars has been characterised by IR spectroscopy (FTIR), thermogravimetry (TG) and elemental analysis. FTIR study provided suitable information to establish differences between coal samples according to their chemical compositions. The reactivity of these samples was also studied and correlated with the coal parameters of mean vitrinite reflectance, fuel ratio and H/C ratio. The data suggest that reactivity as determined can be correlated with the mean vitrinite reflectance, fuel ratio and H/C ratio (0.90). The order of reactivity of samples were; Amasra (S1) (R-m=0.65) > Azdavay (S4) (R-m=0.99) {approx_equal} Armutcuk (S2) (R-m=0.81) {approx_equal} Acenta (S3) (R-m=0.92) > Ac2l2k (S6) (R-m=1.11) Cay (S5) (R-m=1.03) > Sogutozu (S7) (R-m=2.14).

  11. Chemical and Pyrolytic Thermogravimetric Characterization of Nigerian Bituminous Coals

    Directory of Open Access Journals (Sweden)

    Nyakuma Bemgba Bevan

    2016-12-01

    Full Text Available The discovery of new coal deposits in Nigeria presents solutions for nation’s energy crises and prospects for socioeconomic growth and sustainable development. Furthermore, the quest for sustainable energy to limit global warming, climate change, and environmental degradation has necessitated the exploration of alternatives using cleaner technologies such as coal pyrolysis. However, a lack of comprehensive data on physico-chemical and thermal properties of Nigerian coals has greatly limited their utilization. Therefore, the physico-chemical properties, rank (classification, and thermal decomposition profiles of two Nigerian bituminous coals – Afuze (AFZ and Shankodi-Jangwa (SKJ – were examined in this study. The results indicate that the coals contain high proportions of C, H, N, S, O and a sufficiently high heating value (HHV for energy conversion. The coal classification revealed that the Afuze (AFZ coal possesses a higher rank, maturity, and coal properties compared to the Shankodi-Jangwa (SKJ coal. A thermal analysis demonstrated that coal pyrolysis in both cases occurred in three stages; drying (30-200 °C, devolatilization (200-600 °C, and char decomposition (600-1000 °C. The results also indicated that pyrolysis at 1000 °C is not sufficient for complete pyrolysis. In general, the thermochemical and pyrolytic fuel properties indicate that the coal from both places can potentially be utilized for future clean energy applications.

  12. Fuel properties of bituminous coal and pyrolytic oil mixture

    Science.gov (United States)

    Hamdan, Hazlin; Sharuddin, Munawar Zaman; Daud, Ahmad Rafizan Mohamad; Syed-Hassan, Syed Shatir A.

    2014-10-01

    Investigation on the thermal decomposition kinetics of coal-biooil slurry (CBS) fuel prepared at different ratios (100:0,70:30,60:40,0:100) was conducted using a Thermogravimetric Analyzer (TGA). The materials consisted of Clermont bituminous coal (Australia) and bio-oil (also known as pyrolytic oil) from the source of Empty Fruit Bunch (EFB) that was thermally converted by means of pyrolysis. Thermal decomposition of CBS fuel was performed in an inert atmosphere (50mL/min nitrogen) under non-isothermal conditions from room temperature to 1000°C at heating rate of 10°C/min. The apparent activation energy (Ea.) and pre-exponential factor (A) were calculated from the experimental results by using an Arrhenius-type kinetic model which first-order decomposition reaction was assumed. All kinetic parameters were tabulated based on the TG data obtained from the experiment. It was found that, the CBS fuel has higher reactivity than Clermont coal fuel during pyrolysis process, as the addition of pyrolytic oil will reduce the Ea values of the fuel. The thermal profiles of the mixtures showed potential trends that followed the characteristics of an ideal slurry fuel where high degradation rate is desirable. Among the mixture, the optimum fuel was found at the ratio of 60:40 of pyrolytic oil/coal mixtures with highest degradation rate. These findings may contribute to the development of a slurry fuel to be used in the vast existing conventional power plants.

  13. Capacity of Intelligent Underlay and Overlay Network

    DEFF Research Database (Denmark)

    Ling, Yim; Elling, Jan; Nielsen, Thomas Toftegaard

    1996-01-01

    This paper suggests a method of dimensioning the cell configuration of radio sites in a cellular network using the intelligent overlay and underlay (IOU) technique. The traffic capacity has been analysed by means of a teletraffic model, which is developed based on the classical theory of overflow...... and therefore can be used to dimension the network. The model shows that the increase of capacity for a GSM network with 34 frequencies is about 30%. Further capacity enhancement can be achieved by intelligent frequency planning method which is currently being developed...

  14. The hilum overlay sign in a child

    Directory of Open Access Journals (Sweden)

    M J Van Wyk

    2010-12-01

    Full Text Available A 9-month-old girl presented with a 1-month history of coughing. A chest X-ray (CXR was performed, and the antero-posterior view demonstrated the hilum overlay sign. Furthermore, there was absence of the azygo-oesophageal line and bilateral paraspinal lines. The lateral CXR revealed a posterior mediastinal mass. Subsequently, a computed tomogram of the chest confirmed a posterior mediastinal mass, with calcifications and intraspinal extension consistent with neuroblastoma. Histological analysis confirmed this mass as a neuroblastoma.

  15. Practical Coding Schemes for Cognitive Overlay Radios

    CERN Document Server

    Kurniawan, Ernest; Rini, Stefano

    2012-01-01

    We develop practical coding schemes for the cognitive overlay radios as modeled by the cognitive interference channel, a variation of the classical two user interference channel where one of the transmitters has knowledge of both messages. Inspired by information theoretical results, we develop a coding strategy for each of the three parameter regimes where capacity is known. A key feature of the capacity achieving schemes in these regimes is the joint decoding of both users' codewords, which we accomplish by performing a posteriori probability calculation over a combined trellis. The schemes are shown to perform close to the capacity limit with low error rate.

  16. P2P overlay over Simctl

    OpenAIRE

    Sicart López, Gerard Carles

    2016-01-01

    This project intends to find and implement a p2p overlay over the simctl platform. Simctl is used both for teaching and research in the network engineering department. P2P systems became an interesting area since early 2000. Researchers conducted a large amount of research in some challenging areas and, to check their experiments, several implementations and simulators were created. Over time, Internet has evolved and P2P has been widely used for file sharing, but the main structured P2P o...

  17. Overlay Share Mesh for Interactive Group Communication with High Dynamic

    Institute of Scientific and Technical Information of China (English)

    WU Yan-hua; CAI Yun-ze; XU Xiao-ming

    2007-01-01

    An overlay share mesh infrastructure is presented for high dynamic group communication systems, such as distributed interactive simulation (DIS) and distributed virtual environments (DVE). Overlay share mesh infrastructure can own better adapting ability for high dynamic group than tradition multi-tree multicast infrastructure by sharing links among different groups. The mechanism of overlay share mesh based on area of interest (AOI) was discussed in detail in this paper. A large number of simulation experiments were done and the permance of mesh infrastructure was studied. Experiments results proved that overlay mesh infrastructure owns better adaptability than traditional multi-tree infrastructure for high dynamic group communication systems.

  18. Bituminous reference document: synthesis of knowledge on the long time behavior of bituminous packages; Dossier de reference bitume: synthese des connaissances sur le comportement a long terme des colis bitumes

    Energy Technology Data Exchange (ETDEWEB)

    Sercombe, J.; Adenot, F.; Vistoli, P.P.; Parraud, S.; Riglet-Martial, C.; Gwinner, B.; Felines, I.; Tiffreau, C.; Libert, M

    2004-07-01

    This document is a synthesis of the knowledge acquired at the CEA on the behavior of bituminous packages. In this framework, the CEA studied bituminous packages in generic conditions of a package lifetime. The main factors, the evolution mechanisms and influential parameters have been determined and quantitative s simulation have been developed. After a description of the main initial bituminous packages characterizations, the evolutions in saturated and un-saturated environment are exposed. (A.L.B.)

  19. Real cell overlay measurement through design based metrology

    Science.gov (United States)

    Yoo, Gyun; Kim, Jungchan; Park, Chanha; Lee, Taehyeong; Ji, Sunkeun; Jo, Gyoyeon; Yang, Hyunjo; Yim, Donggyu; Yamamoto, Masahiro; Maruyama, Kotaro; Park, Byungjun

    2014-04-01

    Until recent device nodes, lithography has been struggling to improve its resolution limit. Even though next generation lithography technology is now facing various difficulties, several innovative resolution enhancement technologies, based on 193nm wavelength, were introduced and implemented to keep the trend of device scaling. Scanner makers keep developing state-of-the-art exposure system which guarantees higher productivity and meets a more aggressive overlay specification. "The scaling reduction of the overlay error has been a simple matter of the capability of exposure tools. However, it is clear that the scanner contributions may no longer be the majority component in total overlay performance. The ability to control correctable overlay components is paramount to achieve the desired performance.(2)" In a manufacturing fab, the overlay error, determined by a conventional overlay measurement: by using an overlay mark based on IBO and DBO, often does not represent the physical placement error in the cell area of a memory device. The mismatch may arise from the size or pitch difference between the overlay mark and the cell pattern. Pattern distortion, caused by etching or CMP, also can be a source of the mismatch. Therefore, the requirement of a direct overlay measurement in the cell pattern gradually increases in the manufacturing field, and also in the development level. In order to overcome the mismatch between conventional overlay measurement and the real placement error of layer to layer in the cell area of a memory device, we suggest an alternative overlay measurement method utilizing by design, based metrology tool. A basic concept of this method is shown in figure1. A CD-SEM measurement of the overlay error between layer 1 and 2 could be the ideal method but it takes too long time to extract a lot of data from wafer level. An E-beam based DBM tool provides high speed to cover the whole wafer with high repeatability. It is enabled by using the design as a

  20. Hybrid overlay metrology with CDSEM in a BEOL patterning scheme

    Science.gov (United States)

    Leray, Philippe; Jehoul, Christiane; Inoue, Osamu; Okagawa, Yutaka

    2015-03-01

    Overlay metrology accuracy is a major concern for our industry. Advanced logic process require more tighter overlay control for multipatterning schemes. TIS (Tool Induced Shift) and WIS (Wafer Induced Shift) are the main issues for IBO (Image Based Overlay) and DBO (Diffraction Based Overlay). Methods of compensation have been introduced, some are even very efficient to reduce these measured offsets. Another related question is about the overlay target designs. These targets are never fully representative of the design rules, strong efforts have been achieved, but the device cannot be completely duplicated. Ideally, we would like to measure in the device itself to verify the real overlay value. Top down CDSEM can measure critical dimensions of any structure, it is not dependent of specific target design. It can also measure the overlay errors but only in specific cases like LELE (Litho Etch Litho Etch) after final patterning. In this paper, we will revisit the capability of the CDSEM at final patterning by measuring overlay in dedicated targets as well as inside a logic and an SRAM design. In the dedicated overlay targets, we study the measurement differences between design rules gratings and relaxed pitch gratings. These relaxed pitch which are usually used in IBO or DBO targets. Beyond this "simple" LELE case, we will explore the capability of the CDSEM to measure overlay even if not at final patterning, at litho level. We will assess the hybridization of DBO and CDSEM for reference to optical tools after final patterning. We will show that these reference data can be used to validate the DBO overlay results (correctables and residual fingerprints).

  1. Surface Properties of Photo-Oxidized Bituminous Coals: Final report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-09-01

    Natural weathering has a detrimental effect on the hydrophobic nature of coal, which in turn can influence clean-coal recovery during flotation. Few techniques are available that can establish the quality of coal surfaces and that have a short analysis time to provide input for process control. Luminescence emissions which can be quantified with an optical microscope and photometer system, are measurably influenced by degree of weathering as well as by mild storage deterioration. In addition, it has been shown that when vitrinite is irradiated with a relatively high intensity flux of violet- or ultraviolet- light in the presence of air, photo-oxidation of the surface occurs. The combination of measuring the change in luminescence emission intensity with degree of surface oxidation provided the impetus for the current investigation. The principal aim of this research was to determine whether clear correlations could be established among surface oxygen functionality, hydrophobicity induced by photo-oxidation, and measurements of luminescence intensity and alteration. If successful, the project would result in quantitative luminescence techniques based on optical microscopy that would provide a measure of the changes in surface properties as a function of oxidation and relate them to coal cleanability. Two analytical techniques were designed to achieve these goals. Polished surfaces of vitrain bands or a narrow size fraction of powdered vitrain concentrates were photo-oxidized using violet or ultraviolet light fluxes and then changes in surface properties and chemistry were measured using a variety of near-surface analytical techniques. Results from this investigation demonstrate that quantitative luminescence intensity measurements can be performed on fracture surfaces of bituminous rank coals (vitrains) and that the data obtained do reveal significant variations depending upon the level of surface oxidation. Photo-oxidation induced by violet or ultraviolet light

  2. Effect of mix parameters on longevity of bituminous mixtures

    Science.gov (United States)

    Reichle, Clayton Matthew

    This study was performed to evaluate the effects of varying aggregate sources, aggregate gradations on the stripping and rutting potential of bituminous based plant mixes specified by the Missouri Department of Transportation. The different aggregate combinations included two different aggregate sources (Potosi Dolomite and Jefferson City Dolomite) including two variations for the Jefferson City Dolomite mix to simulate a marginally in-specification mix and an out-of-specification but in-field tolerance mix. The "field" mix simulated the marginal mix where field tolerance of high dust and low binder content were maximized. All three mixes were evaluated for stripping susceptibility using the Tensile Strength Ratio (TSR) test and the Hamburg Wheel Tracking Device (HWTD). The mix characteristics (unit weight, effective binder content, and air voids) were used for a Level 3 analysis in the Mechanistic-Empirical Pavement Design Guide (MEPDG) to determine long term pavement distress conditions such as fatigue cracking, rutting, and IRI (smoothness). The Potosi mix exhibited the best resistance to rutting and stripping during both the TSR testing as well as the Hamburg testing. The Jefferson City In-Spec and Out-of-Spec mixes showed less resistance to rutting and stripping in order, respectively. This was expected for the Jefferson City mixes where the aggregate was of lower quality (higher Los Angeles Abrasion, Micro Deval loss, absorption, and deleterious materials). Also, in the case of the Jefferson City Out-of-Spec mix, the binder content was lower. Upon evaluating the mixes using the MEPDG software, it was shown that mix characteristics such as air voids, VMA, and VFA influenced the fatigue cracking, rutting, and IRI predictions to a minor degree.

  3. Carbon molecular sieves from bituminous coal by controlled coke deposition

    Energy Technology Data Exchange (ETDEWEB)

    Vyas, S.N.; Patwardhan, S.R.; Gangadhar, B. (Indian Institute of Technology, Bombay (India). Dept. of Chemical Engineering)

    1992-01-01

    Carbon molecular sieves (CMS) and zeolites are widely used as microporous sieving solids for gas and liquid separations. However, due to hydrophobicity, better thermal stability, and neutrality in both acidic and alkaline media, CMSs have definite advantages over zeolites. In the present work, an effort has been made to develop suitable process conditions for synthesizing CMSs from the locally available bituminous coal. The coal was crushed, milled, and agglomerated with sulfate pulp waste liquor (SPWL) or coal-tar pitch (CTP) as the binders, and then carbonized in nitrogen atmosphere at 800{degree}C for about 60 minutes. In order to narrow down the pore mouth sizes, acetylene and benzene were each cracked separately at 800{degree}C to facilitate the deposition of coke on the char. Acetylene and benzene were cracked for 3 to 10 minutes, and 10 to 30 minutes, respectively. Acetylene cracked samples did not show good separation, probably because of over-coking in deeper locations. In contrast benzene cracked samples were found to be highly suitable for CO{sub 2}-CH{sub 4} separation. The best result (i.e. uptake ratio of 39.9) was obtained for feed benzene entrainment in N{sub 2} of 1.27 x 10{sup -4} g/ml, cracking time of 30 minutes, and this ratio was more than 10 times that of non-coked sample. CMS samples produced using SPWL as binder showed poor O{sub 2}/N{sub 2} uptake ratios throughout (1 to 1.5), whereas samples with CTP as binder showed far more encouraging results, the best uptake ratio being 5.5 for benzene-nitrogen feed stream containing 3.508 x 10{sup -4} g/ml benzene and 5 minutes cracking time. This ratio is about 5.5 times more than that of uncoked sample. 4 tabs., 10 figs., 17 refs.

  4. Diffraction-based overlay metrology for double patterning technologies

    Science.gov (United States)

    Dasari, Prasad; Korlahalli, Rahul; Li, Jie; Smith, Nigel; Kritsun, Oleg; Volkman, Cathy

    2009-03-01

    The extension of optical lithography to 32nm and beyond is made possible by Double Patterning Techniques (DPT) at critical levels of the process flow. The ease of DPT implementation is hindered by increased significance of critical dimension uniformity and overlay errors. Diffraction-based overlay (DBO) has shown to be an effective metrology solution for accurate determination of the overlay errors associated with double patterning [1, 2] processes. In this paper we will report its use in litho-freeze-litho-etch (LFLE) and spacer double patterning technology (SDPT), which are pitch splitting solutions that reduce the significance of overlay errors. Since the control of overlay between various mask/level combinations is critical for fabrication, precise and accurate assessment of errors by advanced metrology techniques such as spectroscopic diffraction based overlay (DBO) and traditional image-based overlay (IBO) using advanced target designs will be reported. A comparison between DBO, IBO and CD-SEM measurements will be reported. . A discussion of TMU requirements for 32nm technology and TMU performance data of LFLE and SDPT targets by different overlay approaches will be presented.

  5. Community overlays upon real-world complex networks

    NARCIS (Netherlands)

    Ge, X.; Wang, H.

    2012-01-01

    Many networks are characterized by the presence of communities, densely intra-connected groups with sparser inter-connections between groups. We propose a community overlay network representation to capture large-scale properties of communities. A community overlay Go can be constructed upon a netwo

  6. EOS: Evolutionary Overlay Service in Peer-to-Peer Systems

    Directory of Open Access Journals (Sweden)

    L. I. Zhijun

    2005-01-01

    Full Text Available The peer-to-peer (P2P systems nowadays can be mainly classified into two categories: structured and structure-less systems based on their overlay organization. The structured systems can achieve determinate efficiency due to their rigorous structure with the cost of losing robustness and vice versa. We provide a semi-structured overlay based on the separation of routing structures and overlay organizations in this paper and the new overlay can achieve determinate efficiency with high robustness. Moreover, the performance of the existing overlay is determined by the initial design and the overlay can not evolve with the information collected. But the new overlay devised in this paper is evolutionary inherent and accompanied by evolving service (EOS, EOS can improve the performance with the running of the P2P systems. Finally, our evolutionary overlay structure is constructed on the basis of linear algebra. So, the EOS can be theoretically analyzed and the results indicate that EOS can work with preferable integrated performance. The experimental results gained on the simulative platform verify the performance of EOS further.

  7. Multi-level Reconfigurable Self-organization in Overlay Services

    NARCIS (Netherlands)

    Pournaras, E.

    2013-01-01

    Large-scale decentralized systems organized in overlay networks are complex to manage. Such systems integrate organizational complexity in the application-level resulting in low abstraction and modularity in their services. This thesis introduces a multi-level conceptual architecture for overlay ser

  8. Finite elements simulation of reflective cracking in asphaltic overlays

    NARCIS (Netherlands)

    Scarpas, A.; De Bondt, A.H.

    1996-01-01

    Overlaying is one of the most popular and cost effective techniques of rehabilitation of cracked pavements. The placing of reinforcement between the overlay and the top layer of the cracked pavement is currently being utilised as a possible technique for delaying the development of cracks into the o

  9. Solidification paths in modified Inconel 625 weld overlay material

    DEFF Research Database (Denmark)

    Chandrasekaran, Karthik; Tiedje, Niels Skat; Hald, John

    2009-01-01

    Inconel 625 is commonly used for overlay welding to protect the base metal against high temperature corrosion. The efficiency of corrosion protection depends on effective mixing of the overlay weld with the base metal and the subsequent segregation of alloy elements during solidification...

  10. Decentralized Overlay for Federation of Enterprise Clouds

    CERN Document Server

    Ranjan, Rajiv

    2008-01-01

    This chapter describes Aneka-Federation, a decentralized and distributed system that combines enterprise Clouds, overlay networking, and structured peer-to-peer techniques to create scalable wide-area networking of compute nodes for high-throughput computing. The Aneka-Federation integrates numerous small scale Aneka Enterprise Cloud services and nodes that are distributed over multiple control and enterprise domains as parts of a single coordinated resource leasing abstraction. The system is designed with the aim of making distributed enterprise Cloud resource integration and application programming flexible, efficient, and scalable. The system is engineered such that it: enables seamless integration of existing Aneka Enterprise Clouds as part of single wide-area resource leasing federation; self-organizes the system components based on a structured peer-to-peer routing methodology; and presents end-users with a distributed application composition environment that can support variety of programming and execu...

  11. Weld overlay cladding with iron aluminides

    Energy Technology Data Exchange (ETDEWEB)

    Goodwin, G.M. [Oak Ridge National Lab., TN (United States)

    1995-08-01

    The hot and cold cracking tendencies of some early iron aluminide alloy compositions have limited their use in applications where good weldability is required. Using hot crack testing techniques invented at ORNL, and experimental determinations of preheat and postweld heat treatment needed to avoid cold cracking, we have developed iron aluminide filler metal compositions which can be successfully used to weld overlay clad various substrate materials, including 9Cr-1Mo steel, 2-1/4Cr-1Mo steel, and 300-series austenitic stainless steels. Dilution must be carefully controlled to avoid crack-sensitive deposit compositions. The technique used to produce the current filler metal compositions is aspiration-casting, i.e. drawing the liquid from the melt into glass rods. Future development efforts will involve fabrication of composite wires of similar compositions to permit mechanized gas tungsten arc (GTA) and/or gas metal arc (GMA) welding.

  12. Characterization of waferstepper and process related front- to backwafer overlay errors in bulk micro machining using electrical overlay test structures

    NARCIS (Netherlands)

    Van Zeijl, H.W.; Bijnen, F.G.C.; Slabbekoorn, J.

    2004-01-01

    To validate the Front- To Backwafer Alignment (FTBA) calibration and to investigate process related overlay errors, electrical overlay test structures are used that requires FTBA [1]. Anisotropic KOH etch through the wafer is applied to transfer the backwafer pattern to the frontwafer. Consequently,

  13. Following changes in the constitution of rapidly heated bituminous vitrinites

    Science.gov (United States)

    Mathews, Jonathan Paul

    1998-12-01

    Molecular models, which represent the constitution (the chemical and physical structure) of bituminous vitrinites from the Upper Freeport and Lewiston-Stockton coal seams, were generated computationally. Incorporation of physical data significantly reduced the number of possible structures and forced the inclusion of hydroaromatic structures. This limited the bonding types and the extent of bonding to the coal matrix. The use of vitrinites (telocollinite) rather than whole coals reduced the complexity of the molecular structures and precluded incorporation of other maceral functionalities (such as long chain aliphatics or highly condensed aromatic structures) into the models. A narrow size fraction of each vitrinite was pyrolyzed in a drop-tube reactor under conditions representative of the devolatilization stage of pulverized coal combustion. The collected chars represented the transition from vitrinite to almost fully devolatilized char. Computational fluid dynamics were used to calculate the range of time-temperature histories of the particles in the reactor. Significant variation (up to 400sp°C and 0.15 s residence time) was found within a cuts primarily due to different extents of swelling, different particle sizes and the associated differences in mass loss. The vitrinite models were subjected to via various pyrolysis mechanisms and the resulting char structure compared to those of the experimentally-produced chars. The breaking of bonds in order of bond strengths did not produce a reasonable initial char structure; one which was similar to the parent vitrinite. The weaker bonds tend to be aliphatic in nature, hence breaking these bonds resulted in a structure that was too aromatic and hydrogen deficient. 'Rules' of pyrolysis, which were reasonable for the transitions of this rank of vitrinite under rapid heating conditions were proposed. Five-membered rings, either formed via ring condensation or originally present in the vitrinite, introduce curvature into

  14. The results of experimental asbestos research into the washing of bituminized sandstone

    Energy Technology Data Exchange (ETDEWEB)

    Agalarov, M.S.; Mangasarova, A.G.; Zhirnov, B.I.

    1981-01-01

    Bituminized sandstone was exposed to washing by its removal at the Kirmak deposits under the operation of ''Leninneft''' of the National Mining Institute, and the National Mining Institutes Umbaki deposits under the operation of ''Karagandaneft'''. Various compositions were employed as washing agents including an oil-water mixture. The composition of bituminus oil is given and the method used in the preparation of the mixture is presented. Research has indicated that the coefficient for washing the bituminized sandstone hinges on the various compositions of the oil-water washing fluid and the types of bitumins when this process is undertaken at temperatures of 291-293 degrees Calvin. At temperatures of 358-363 degrees Calvin, this relationship disappears and the coefficient for washing aproaches one.

  15. Global market trade policy analysis for petroleum oils and oils obtained from bituminous minerals, crude

    Directory of Open Access Journals (Sweden)

    Bagheri, F.

    2012-01-01

    Full Text Available This article is based on surveying the custom tariffs imposed on the world export market of Petroleum Oils and Oils Obtained from Bituminous Minerals, Crude. We obtained the data according to the most updated available data provided online by UNCTAD and World Bank. The results indicate that none of the 142 countries in the world market of this product have imposed non-tariff trade barriers on the import of Petroleum Oils and Oils Obtained from Bituminous Minerals, Crude. The developed countries and the countries with transition economies are the main world import partners. European Union, United States, China, Japan, South Korea, Canada, Singapore, Taiwan, Thailand, South Africa, Australia, Turkey, Brazil, Sweden and Belarus are the examples and have imposed low custom tariffs on Petroleum Oils and Oils Obtained from Bituminous Minerals, Crude.

  16. Advanced diffraction-based overlay for double patterning

    Science.gov (United States)

    Li, Jie; Liu, Yongdong; Dasari, Prasad; Hu, Jiangtao; Smith, Nigel; Kritsun, Oleg; Volkman, Catherine

    2010-03-01

    Diffraction based overlay (DBO) technologies have been developed to address the tighter overlay control challenges as the dimensions of integrated circuit continue to shrink. Several studies published recently have demonstrated that the performance of DBO technologies has the potential to meet the overlay metrology budget for 22nm technology node. However, several hurdles must be cleared before DBO can be used in production. One of the major hurdles is that most DBO technologies require specially designed targets that consist of multiple measurement pads, which consume too much space and increase measurement time. A more advanced spectroscopic ellipsometry (SE) technology-Mueller Matrix SE (MM-SE) is developed to address the challenge. We use a double patterning sample to demonstrate the potential of MM-SE as a DBO candidate. Sample matrix (the matrix that describes the effects of the sample on the incident optical beam) obtained from MM-SE contains up to 16 elements. We show that the Mueller elements from the off-diagonal 2x2 blocks respond to overlay linearly and are zero when overlay errors are absent. This superior property enables empirical DBO (eDBO) using two pads per direction. Furthermore, the rich information in Mueller matrix and its direct response to overlay make it feasible to extract overlay errors from only one pad per direction using modeling approach (mDBO). We here present the Mueller overlay results using both eDBO and mDBO and compare the results with image-based overlay (IBO) and CD-SEM results. We also report the tool induced shifts (TIS) and dynamic repeatability.

  17. Weld overlay cladding with iron aluminides

    Energy Technology Data Exchange (ETDEWEB)

    Goodwin, G.M. [Oak Ridge National Lab., TN (United States)

    1997-12-01

    The author has established a range of compositions for these alloys within which hot cracking resistance is very good, and within which cold cracking can be avoided in many instances by careful control of welding conditions, particularly preheat and postweld heat treatment. For example, crack-free butt welds have been produced for the first time in 12-mm thick wrought Fe{sub 3}Al plate. Cold cracking, however, still remains an issue in many cases. The author has developed a commercial source for composite weld filler metals spanning a wide range of achievable aluminum levels, and are pursuing the application of these filler metals in a variety of industrial environments. Welding techniques have been developed for both the gas tungsten arc and gas metal arc processes, and preliminary work has been done to utilize the wire arc process for coating of boiler tubes. Clad specimens have been prepared for environmental testing in-house, and a number of components have been modified and placed in service in operating kraft recovery boilers. In collaboration with a commercial producer of spiral weld overlay tubing, the author is attempting to utilize the new filler metals for this novel application.

  18. nowCOAST's Map Service for Political Map Overlays

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Map Information: This nowCOAST map service provides map overlays depicting the boundaries of U.S. states, territories, counties and townships/county subdivisions,...

  19. SPHERE: a scalable multicast framework in overlay networks

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    This paper presents Sphere, a scalable multicast framework in overlay network. Sphere is a highly efficient, self-organizing and robust multicast protocol overlayed on the Internet. The main contributions of this paper are twofold. First, Sphere organizes the control topology of overlay network in two directions: horizontal and vertical. The horizontal meshes are used to locate and organize hosts in tracks, and the vertical meshes are used to manage the data paths between tracks. Second, Sphere balances stress and stretch of the overlay network by assigning hosts into different tracks and clusters. This structure distributes stress on the multicast trees uniformly, and meantime makes path stretch as small as possible.Simulations results show that Sphere can support multicast with large group size and has good performance on organizing meshes and building data delivery trees.

  20. MICROSTRUCTURES AND OXIDATION RESISTANCE OF Fe3Al WELD OVERLAY

    Institute of Scientific and Technical Information of China (English)

    X.G.Min; X.Q.Yu; Y.S.Sun; J.R.Sun

    2001-01-01

    Using the Fe3Al electrode through manual arc surfacing (MAS),Fe3Al coatings havebeen deposited on the stainless steel substrate.The microstructures,hardness andoxidation resistance of the weld overlay have been investigated.The results show thatcrack-free overlays can be obtained when pre-heating of the substrate at 500℃ andpostweld heat treatment at 700℃ were used.Elements of Al,Cr,Ni etc.transferredbetween the substrate and the overlay,but this does not influence the microhardnessof the substrate and the Fe3Al overlay.Oxidation tests show that the Fe3Al overlayshave excellent oxidation resistance in comparison with the stainless steel substrate at800℃ and 900℃.

  1. Government Districts, Other - MO 2014 Springfield Conditional Overlay Districts (SHP)

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — Conditional Overlay District polygons for the City of Springfield, inside city limits only. Created and maintained by the GIS Division of the Information Systems...

  2. Zoning Districts - MO 2011 Springfield Conditional Overlay Districts (SHP)

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — Conditional Overlay District polygons for the City of Springfield, inside city limits only. Created and maintained by the GIS Division of the Information Systems...

  3. Noise Reduction Properties of an Experimental Bituminous Slurry with Crumb Rubber Incorporated by the Dry Process

    Directory of Open Access Journals (Sweden)

    Moisés Bueno

    2014-08-01

    Full Text Available Nowadays, cold technology for asphalt pavement in the field of road construction is considered as an alternative solution to conventional procedures from both an economic and environmental point of view. Among these techniques, bituminous slurry surfacing is obtaining an important role due to the properties of the obtained wearing course. The functional performance of this type of surfaces is directly related to its rough texture. Nevertheless, this parameter has a significant influence on the tire/road noise generation. To reduce this undesirable effect on the sound performance, new designs of elastic bituminous slurries have been developed. Within the FENIX project, this work presents the acoustical characterization of an experimental bituminous slurry with crumb rubber from wasted automobile tires incorporated by the dry process. The obtained results show that, under controlled operational parameters, the close proximity sound levels associated to the experimental slurry are considerably lower than those emitted by a conventional slurry wearing course. However, after one year of supporting traffic loads and different weather conditions, the evaluated bituminous slurry, although it conserves the original noise reduction properties in relation to the conventional one, noticeably increases the generated sound emission. Therefore, it is required to continue improving the design of experimental surfaces in order to enhance its long-term performance.

  4. Chemomechanics of Damage Accumulation and Damage-Recovery Healing in Bituminous Asphalt Binders

    NARCIS (Netherlands)

    Pauli, A.T.

    2014-01-01

    As a contribution to the development of mutli-scale multi-physics approaches to modelling pavement performance, the present thesis considers the topic of damage accumulation accompanied by damage recover self-healing of the bituminous asphalt phase of pavement systems. It is found insightful that b

  5. 8th RILEM International Symposium on Testing and Characterization of Sustainable and Innovative Bituminous Materials

    CERN Document Server

    Partl, Manfred

    2016-01-01

    This work presents the results of RILEM TC 237-SIB (Testing and characterization of sustainable innovative bituminous materials and systems). The papers have been selected for publication after a rigorous peer review process and will be an invaluable source to outline and clarify the main directions of present and future research and standardization for bituminous materials and pavements. The following topics are covered: - Characterization of binder-aggregate interaction - Innovative testing of bituminous binders, additives and modifiers - Durability and aging of asphalt pavements - Mixture design and compaction analysis - Environmentally sustainable materials and technologies - Advances in laboratory characterization of bituminous materials - Modeling of road materials and pavement performance prediction - Field measurement and in-situ characterization - Innovative materials for reinforcement and interlayer systems - Cracking and damage characterization of asphalt pavements - Rec...

  6. Microstructural self-healing of bituminous materials: Combined experimental and numerical study

    NARCIS (Netherlands)

    Pauli, A.; Schmets, A.J.M.; Kasbergen, C.; Varveri, K.; Scarpas, A.

    2013-01-01

    Bituminous materials form a class of materials that possess the intrinsic ability to selfheal. This self-healing capability is evidenced by the observation that the service life of these materials ‘in the field’ exceeds the service life as predicted by standard mechanical laboratory tests. This mism

  7. Augmenting reality in Direct View Optical (DVO) overlay applications

    Science.gov (United States)

    Hogan, Tim; Edwards, Tim

    2014-06-01

    The integration of overlay displays into rifle scopes can transform precision Direct View Optical (DVO) sights into intelligent interactive fire-control systems. Overlay displays can provide ballistic solutions within the sight for dramatically improved targeting, can fuse sensor video to extend targeting into nighttime or dirty battlefield conditions, and can overlay complex situational awareness information over the real-world scene. High brightness overlay solutions for dismounted soldier applications have previously been hindered by excessive power consumption, weight and bulk making them unsuitable for man-portable, battery powered applications. This paper describes the advancements and capabilities of a high brightness, ultra-low power text and graphics overlay display module developed specifically for integration into DVO weapon sight applications. Central to the overlay display module was the development of a new general purpose low power graphics controller and dual-path display driver electronics. The graphics controller interface is a simple 2-wire RS-232 serial interface compatible with existing weapon systems such as the IBEAM ballistic computer and the RULR and STORM laser rangefinders (LRF). The module features include multiple graphics layers, user configurable fonts and icons, and parameterized vector rendering, making it suitable for general purpose DVO overlay applications. The module is configured for graphics-only operation for daytime use and overlays graphics with video for nighttime applications. The miniature footprint and ultra-low power consumption of the module enables a new generation of intelligent DVO systems and has been implemented for resolutions from VGA to SXGA, in monochrome and color, and in graphics applications with and without sensor video.

  8. EXPERIENCE WITH OVERLAY TYMPANOPLASTY IN 83 CHINESE PATIENTS

    Institute of Scientific and Technical Information of China (English)

    PENG Bengang; MIAO Xutao; WANG Xin; ZHU Sixiang; SUN Yiqing

    2014-01-01

    Background In many European and American hospitals, represented by the House Ear Clinic (HEC), the overlay tympanoplasty is used with rare exception, with simultaneous canal wall up or down mastoidectomy being taken if needed. In China, underlay tympanoplasty is used across the country, but the overlay tech-nique is used rarely. The aim of the current study was to report the authors’experience with overlay tympa-noplasty in 83 Chinese patients and study its value. Methods Eight-three patients (86 ears) underwent over-lay tympanoplasty in accordance to the standard of the HEC. The patients were followed up and conditions of the external auditory canal, tympanic membrane and hearing were reviewed and analyzed. Results All patients gained stage I incision healing. The size of external auditory canal and tympanic membrane mor-phology were satisfactory. Hearing either remained unchanged or improved. There were no hearing deterio-ration or serious complications. Conclusions Overlay tympanoplasty carries positive value in treating chron-ic otitis media and cholesteatoma with the merits of procedure standardization, adequate operative exposure, thorough disease elimination and extensive adaptation.

  9. Instructional geographic information science Map overlay and spatial abilities

    Science.gov (United States)

    Tricot, Thomas Alexander, II

    The fundamental goal of this study is to determine if the complex spatial concept of map overlay can be effectively learned by young adolescents through the utilization of an instructional technique based within the foundations of Instructional Geographic Information Science (InGIScience). Percent correct and reaction times were the measures used to analyze the ability of young adolescents to learn the intersect, erase, and union functions of map overlay. The ability to solve for missing inputs, output, or function was also analyzed. Young adolescents of the test group scored higher percent correct and recorded faster reaction times than those of the control group or adults of the expert group by the end of the experiment. The intersect function of map overlay was more difficult in terms of percent correct and reaction time than the erase or union functions. Solving for the first or second input consistently resulted in lower percent correct and higher reaction times throughout the experiment. No overall performance differences were shown to exist between males and females. Results of a subjective "real-world" test also indicated learning by young adolescents. This study has shown that the practice of repetitive instruction and testing has proven effective for enhancing spatial abilities with regard to the map overlay concept. This study found that with practice, young adolescents can learn the map overlay concept and perform at levels equal to or greater than adults. This study has helped to answer the question of whether this development of spatial abilities is possible.

  10. Location-Aware Cross-Layer Design Using Overlay Watermarks

    Directory of Open Access Journals (Sweden)

    Xianbin Wang

    2007-01-01

    Full Text Available A new orthogonal frequency division multiplexing (OFDM system embedded with overlay watermarks for location-aware cross-layer design is proposed in this paper. One major advantage of the proposed system is the multiple functionalities the overlay watermark provides, which includes a cross-layer signaling interface, a transceiver identification for position-aware routing, as well as its basic role as a training sequence for channel estimation. Wireless terminals are typically battery powered and have limited wireless communication bandwidth. Therefore, efficient collaborative signal processing algorithms that consume less energy for computation and less bandwidth for communication are needed. Transceiver aware of its location can also improve the routing efficiency by selective flooding or selective forwarding data only in the desired direction, since in most cases the location of a wireless host is unknown. In the proposed OFDM system, location information of a mobile for efficient routing can be easily derived when a unique watermark is associated with each individual transceiver. In addition, cross-layer signaling and other interlayer interactive information can be exchanged with a new data pipe created by modulating the overlay watermarks. We also study the channel estimation and watermark removal techniques at the physical layer for the proposed overlay OFDM. Our channel estimator iteratively estimates the channel impulse response and the combined signal vector from the overlay OFDM signal. Cross-layer design that leads to low-power consumption and more efficient routing is investigated.

  11. Overlay metrology solutions in a triple patterning scheme

    Science.gov (United States)

    Leray, Philippe; Mao, Ming; Baudemprez, Bart; Amir, Nuriel

    2015-03-01

    Overlay metrology tool suppliers are offering today several options to their customers: Different hardware (Image Based Overlay or Diffraction Based Overlay), different target designs (with or without segmentation) or different target sizes (from 5 um to 30 um). All these variations are proposed to resolve issues like robustness of the target towards process variations, be more representative of the design or increase the density of measurements. In the frame of the development of a triple patterning BEOL scheme of 10 nm node layer, we compare IBO targets (standard AIM, AIMid and multilayer AIMid). The metrology tools used for the study are KLA-Tencor's nextgeneration Archer 500 system (scatterometry- and imaging-based measurement technologies on the same tool). The overlay response and fingerprint of these targets will be compared using a very dense sampling (up to 51 pts per field). The benefit of indie measurements compared to the traditional scribes is discussed. The contribution of process effects to overlay values are compared to the contribution of the performance of the target. Different targets are combined in one measurement set to benefit from their different strengths (performance vs size). The results are summarized and possible strategies for a triple patterning schemes are proposed.

  12. High-order distortion control using a computational prediction method for device overlay

    Science.gov (United States)

    Kang, Young-Seog; Affentauschegg, Cedric; Mulkens, Jan; Kim, Jang-Sun; Shin, Ju-Hee; Kim, Young-Ha; Nam, Young-Sun; Choi, Young-Sin; Ha, Hunhwan; Lee, Dong-Han; Lee, Jae-il; Rizvi, Umar; Geh, Bernd; van der Heijden, Rob; Baselmans, Jan; Kwon, Oh-Sung

    2016-04-01

    As a result of the continuously shrinking features of the integrated circuit, the overlay budget requirements have become very demanding. Historically, overlay has been performed using metrology targets for process control, and most overlay enhancements were achieved by hardware improvements. However, this is no longer sufficient, and we need to consider additional solutions for overlay improvements in process variation using computational methods. In this paper, we present the limitations of third-order intrafield distortion corrections based on standard overlay metrology and propose an improved method which includes a prediction of the device overlay and corrects the lens aberration fingerprint based on this prediction. For a DRAM use case, we present a computational approach that calculates the overlay of the device pattern using lens aberrations as an additional input, next to the target-based overlay measurement result. Supporting experimental data are presented that demonstrate a significant reduction of the intrafield overlay fingerprint.

  13. Transformism in Alberta: The Environmental Political Economy of the Bituminous Sands

    Science.gov (United States)

    Katz-Rosene, Ryan

    This thesis attempts to help establish environmental political economy as a viable academic field while providing an example of work in the discipline. It offers an analysis of societal processes resulting in the co-optation and/or neutralization of critical environmentalist ideas. Using Alberta's bituminous sands as a case study, and a Gramsci-influenced eco-Marxist theory as a foundation, the thesis argues that the term 'environmental transformism' (inspired by the Gramscian term trasformismo) is helpful in describing and framing such processes. Accordingly, the ensuing chapters provide an analysis of why environmental transformism is happening in Alberta, and demonstrate how this mechanism works at protecting the status quo from threatening ideologies, thereby consolidating neoliberal capitalism. A concluding argument discusses the inherent dangers posed to society by the transformism of certain environmental subjectivities. The thesis begins by introducing the contentious social and environmental issues surrounding the development of the bituminous sands.

  14. Using Mobile Agents and Overlay Networks to Secure Electrical Networks

    Energy Technology Data Exchange (ETDEWEB)

    Dawes, Neal A.; Prosser, Bryan J.; Fulp, Errin W.; McKinnon, Archibald D.

    2013-02-11

    ABSTRACT The use of wandering, mobile agents can provide a robust approach for managing, monitoring, and securing electrical distribution networks. However, the topological structure of electrical networks can affect system performance. For example, if the multi-agent system relies on a regular inspection rate (on average, points of interest are inspected with equal frequency), then locations that are not well connected will on average be inspected less frequently. This paper discusses creation and use of overlay networks that create a virtual grid graph can provide faster coverage and a more uniform average agent sampling rate. Using overlays agents wander a virtual neighborhood consisting of only points of interest that are interconnected in a regular fashion (each point has the same number of neighbors). Experimental results will show that an overlay can often provide better network coverage and a more uniform inspection rate, which can improve cyber security by providing a faster detection of threats.

  15. Using Mobile Agents and Overlay Networks to Secure Electrical Netoworks

    Energy Technology Data Exchange (ETDEWEB)

    Dawes, Neal A.; Prosser, Bryan J.; Fulp, Errin W.; McKinnon, Archibald D.

    2013-04-01

    ABSTRACT The use of wandering, mobile agents can provide a robust approach for managing, monitoring, and securing electrical distribution networks. However, the topological structure of electrical networks can affect system performance. For example, if the multi-agent system relies on a regular inspection rate (on average, points of interest are inspected with equal frequency), then locations that are not well connected will on average be inspected less frequently. This paper discusses creation and use of overlay networks that create a virtual grid graph can provide faster coverage and a more uniform average agent sampling rate. Using overlays agents wander a virtual neighborhood consisting of only points of interest that are interconnected in a regular fashion (each point has the same number of neighbors). Experimental results will show that an overlay can often provide better network coverage and a more uniform inspection rate, which can improve cyber security by providing a faster detection of threats

  16. A Proactive Tree Recovery Mechanism for Resilient Overlay Multicast

    Directory of Open Access Journals (Sweden)

    Poorna Satyanarayana B.

    2012-06-01

    Full Text Available Overlay multicast constructs a multicast delivery tree among end hosts. An important problem for making overlay multicast more dependable is how to recover from node departures in order to minimize the disruption of service to those affected nodes. In this paper, we propose a proactive tree recovery mechanism to make the overlay multicast resilient to these failures and unexpected events. The salient feature of the approach is that rescue plans for multiple non-leaf nodes can work together for their respective children when they fail or leave at the same time. Extensive simulations demonstrate that our proactive approach can recover from node departures much faster than reactive methods, while the quality of trees restored and the cost of recovery are reasonable

  17. Cooperative Resource Pricing in Service Overlay Networks for Mobile Agents

    Science.gov (United States)

    Nakano, Tadashi; Okaie, Yutaka

    The success of peer-to-peer overlay networks depends on cooperation among participating peers. In this paper, we investigate the degree of cooperation among individual peers required to induce globally favorable properties in an overlay network. Specifically, we consider a resource pricing problem in a market-oriented overlay network where participating peers sell own resources (e.g., CPU cycles) to earn energy which represents some money or rewards in the network. In the resource pricing model presented in this paper, each peer sets the price for own resource based on the degree of cooperation; non-cooperative peers attempt to maximize their own energy gains, while cooperative peers maximize the sum of own and neighbors' energy gains. Simulation results are presented to demonstrate that the network topology is an important factor influencing the minimum degree of cooperation required to increase the network-wide global energy gain.

  18. Structural Design of Pavement Overlays Based on Functional Parameters

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    This paper reports a practical pavement overlay design methodbased on PCI (Pavement Condition Index). Current pavement investigation method (JTJ 073-96) is compared to the ASTM D 5340, which is the standard test method for airport pavement condition evaluation initially developed for US Air Force. The deficiency in the calculation of PCI based on field data in JTJ 073 is discussed. The proposed design method is compared to AASHTO overlay design method with good agreement. The paper concludes with an example illustrating how the existing pavement structural capacity is related to pavement distress survey results. The presented design method can be used in the design for overlay rehabilitation of pavements of highways, urban streets and airports.

  19. Ductile film delamination from compliant substrates using hard overlayers

    Energy Technology Data Exchange (ETDEWEB)

    Cordill, M.J. [Erich Schmid Institute of Materials Science, Austrian Academy of Sciences (Austria); Marx, V.M.; Kirchlechner, C. [Max-Plank-Insitut für Eisenforschung GmbH, Düsseldorf (Germany)

    2014-11-28

    Flexible electronic devices call for copper and gold metal films to adhere well to polymer substrates. Measuring the interfacial adhesion of these material systems is often challenging, requiring the formulation of different techniques and models. Presented here is a strategy to induce well defined areas of delamination to measure the adhesion of copper films on polyimide substrates. The technique utilizes a stressed overlayer and tensile straining to cause buckle formation. The described method allows one to examine the effects of thin adhesion layers used to improve the adhesion of flexible systems. - Highlights: • Measuring the adhesion energies of ductile metal–polymer interfaces is difficult. • A Cu film would plastically deform under tensile strain without a Cr overlayer. • A Cr overlayer forces cracking and induces buckling between the crack fragments. • The adhesion energy of the metal–polymer interface can be measured.

  20. Characteristics of the gasoline fraction obtained by thermodestruction of bituminous oil

    Energy Technology Data Exchange (ETDEWEB)

    Kleyev, A.M.; Margulis, B.Y.; Martynov, A.A.; Vigdergauz, M.S.

    1979-01-01

    A chromatographic evaluation of the 35-95/sup 0/C gasoline fraction obtained by thermal decomposition of bituminous oil was carried out. The initial analysis involving liquid chromatography in conjunction with fluorescent indicator spectra pointed to the presence of aromatic, olefinic, and paraffin fractions, which were subsequently analyzed by gas chromatography. The final results indicated that thermal destruction by means of a gas generator yields products similar to those obtained by oxidative cracking.

  1. Study on Plastic Coated Overburnt Brick Aggregate as an Alternative Material for Bituminous Road Construction

    OpenAIRE

    Dipankar Sarkar; Manish Pal; Sarkar, Ashoke K.

    2016-01-01

    There are different places in India where natural stone aggregates are not available for constructional work. Plastic coated OBBA can solve the problem of shortage of stone aggregate to some extent. The engineers are always encouraged to use locally available materials. The present investigation is carried out to evaluate the plastic coated OBBA as an alternative material for bituminous road construction. Shredded waste plastics are mixed with OBBA in different percentages as 0.38, 0.42, 0.46...

  2. Parameters which Affect the Stiffness of Bitumen and Bituminous Hot Mixes

    OpenAIRE

    2001-01-01

    This paper deals with bitumen and bituminous mixes, using suitable mathematical models that take into account the parameters affecting their elastic and plastic stiffnesses. These parameters are stress level and acting time, penetration index, softening time and temperature. Viscosity and the total acting time of the load affect the elastic stiffness of bitumen. The elastic stiffness of bitumen and the voluminous concentration of the aggregate influence the elastic stiffness of th...

  3. Sphagnum Moss in the Athabasca Bituminous Sands Region Reveals No Significant Atmospheric Contamination by "Heavy Metals"

    OpenAIRE

    SHOTYK W.; BELLAND Rene; DUKE John; KEMPTER Heike; KRACHLER MICHAEL; NOERNBERG Tommy; VILE Melanie; WIEDER Kelman; Zaccone, Claudio; Zhang, Shuangquan

    2014-01-01

    Sphagnum moss were collected from three sites at each of twenty-one ombrotrophic (rain-fed) peat bogs in the vicinity of and surrounding open pit mines and upgrading facilities of Athabasca Bituminous Sands in Alberta. Compared with contemporary Sphagnum moss from multiple sites at each of four bogs in rural locations of southern Germany, the AB mosses yielded lower concentrations of Ag, Cd, Ni, Pb, Sb and Tl, similar concentrations of Mo, but greater concentrations of Ba, Th and V. ...

  4. Study on Plastic Coated Overburnt Brick Aggregate as an Alternative Material for Bituminous Road Construction

    Directory of Open Access Journals (Sweden)

    Dipankar Sarkar

    2016-01-01

    Full Text Available There are different places in India where natural stone aggregates are not available for constructional work. Plastic coated OBBA can solve the problem of shortage of stone aggregate to some extent. The engineers are always encouraged to use locally available materials. The present investigation is carried out to evaluate the plastic coated OBBA as an alternative material for bituminous road construction. Shredded waste plastics are mixed with OBBA in different percentages as 0.38, 0.42, 0.46, 0.50, 0.54, and 0.60 of the weight of brick aggregates. Marshall Method of mix design is carried out to find the optimum bitumen content of such bituminous concrete mix prepared by plastic coated OBBA. Bulk density, Marshall Stability, flow, Marshall Quotient, ITS, TSR, stripping, fatigue life, and deformations have been determined accordingly. Marshall Stability value of 0.54 percent of plastic mix is comparatively higher than the other mixes except 0.60 percent of plastic mix. Test results are within the prescribed limit for 0.54 percent of plastic mix. There is a significant reduction in rutting characteristics of the same plastic mix. The fatigue life of the mix is also significantly higher. Thus plastic coated OBBA is found suitable in construction of bituminous concrete road.

  5. Continuous bench-scale slurry catalyst testing direct coal liquefaction rawhide sub-bituminous coal

    Energy Technology Data Exchange (ETDEWEB)

    Bauman, R.F.; Coless, L.A.; Davis, S.M. [and others

    1995-12-31

    In 1992, the Department of Energy (DOE) sponsored research to demonstrate a dispersed catalyst system using a combination of molybdenum and iron precursors for direct coal liquefaction. This dispersed catalyst system was successfully demonstrated using Black Thunder sub-bituminous coal at Wilsonville, Alabama by Southern Electric International, Inc. The DOE sponsored research continues at Exxon Research and Development Laboratories (ERDL). A six month continuous bench-scale program using ERDL`s Recycle Coal Liquefaction Unit (RCLU) is planned, three months in 1994 and three months in 1995. The initial conditions in RCLU reflect experience gained from the Wilsonville facility in their Test Run 263. Rawhide sub-bituminous coal which is similar to the Black Thunder coal tested at Wilsonville was used as the feed coal. A slate of five dispersed catalysts for direct coal liquefaction of Rawhide sub-bituminous coal has been tested. Throughout the experiments, the molybdenum addition rate was held constant at 100 wppm while the iron oxide addition rate was varied from 0.25 to 1.0 weight percent (dry coal basis). This report covers the 1994 operations and accomplishments.

  6. JV Task 126 - Mercury Control Technologies for Electric Utilities Burning Bituminous Coal

    Energy Technology Data Exchange (ETDEWEB)

    Jason Laumb; John Kay; Michael Jones; Brandon Pavlish; Nicholas Lentz; Donald McCollor; Kevin Galbreath

    2009-03-29

    The EERC developed an applied research consortium project to test cost-effective mercury (Hg) control technologies for utilities burning bituminous coals. The project goal was to test innovative Hg control technologies that have the potential to reduce Hg emissions from bituminous coal-fired power plants by {ge}90% at costs of one-half to three-quarters of current estimates for activated carbon injection (ACI). Hg control technology evaluations were performed using the EERC's combustion test facility (CTF). The CTF was fired on pulverized bituminous coals at 550,000 Btu/hr (580 MJ/hr). The CTF was configured with the following air pollution control devices (APCDs): selective catalytic reduction (SCR) unit, electrostatic precipitator (ESP), and wet flue gas desulfurization system (WFDS). The Hg control technologies investigated as part of this project included ACI (three Norit Americas, Inc., and eleven Envergex sorbents), elemental mercury (Hg{sup 0}) oxidation catalysts (i.e., the noble metals in Hitachi Zosen, Cormetech, and Hitachi SCR catalysts), sorbent enhancement additives (SEAs) (a proprietary EERC additive, trona, and limestone), and blending with a Powder River Basin (PRB) subbituminous coal. These Hg control technologies were evaluated separately, and many were also tested in combination.

  7. A fiber-reinforced composite structure for the repair of thermally cracked bituminous pavements

    Science.gov (United States)

    Frantzen, Jeffrey Alan

    1998-10-01

    The apparatus under development in this project is a structural component or beam fabricated from a fiber reinforced plastic composite (FRPC). The FRPC beam is a structural repair component intended to bridge a deteriorated thermal crack in full depth bituminous pavements or partial depth bituminous pavements over portland cement concrete. The bridging action provided by the FRPC beam is intended to minimize roughness through the repaired area for up to five years, eliminate reappearance of the deteriorated crack, and provide a controlled expansion crack that can be treated with standard sealing techniques. This apparatus is designed for maintenance use as a field expedient, semi-permanent repair using tools that are commonly available at the Area Maintenance level. Three FRPC beams were constructed for field trial in a thermally cracked, full depth bituminous pavement on US-36 east of Hiawatha, Kansas. Each of the beams were instrumented with bonded metal foil strain gages and field installation by KDOT Maintenance forces was done in August and September of 1997. The FRPC beams have been evaluated since installation and this evaluation will continue for up to five years. Evaluation of the beams has been accomplished through static load tests using the strain gage instrumentation and Falling Weight Deflectometer measurements. The FRPC beams have performed satisfactorily as of the date of writing.

  8. OVERLAY DENTURES: A REVIEW AND REPORT OF FOUR CASES

    Directory of Open Access Journals (Sweden)

    Deeksha SHARMA

    2013-12-01

    Full Text Available Patients with ectodermal dysplasia or having under‑ gone cleft surgery with anodontia or hypodontia, hypo‑ plastic conical teeth and patients with severely worn dentition are difficult to treat because of the poor remaining tooth structure. These patients often exhibit loss of vertical dimension of occlusion and aesthetic problems and usually need complex prosthetic treatments. Financial constraints or other priorities often restrict one from choosing the most desirable treatment. The overlay removable denture is a covering prosthesis partially supported by natural teeth, tooth roots, or dental implants, providing an efficient alter‑ native of treatment. Clinical reports describe the various applications of overlay dentures.

  9. Implementing a Trust Overlay Framework for Digital Ecosystems

    Science.gov (United States)

    Malone, Paul; McGibney, Jimmy; Botvich, Dmitri; McLaughlin, Mark

    Digital Ecosystems, being decentralised in nature, are inherently untrustworthy environments. This is due to the fact that these environments lack a centralised gatekeeper and identity provider. In order for businesses to operate in these environments there is a need for security measures to support accountability and traceability. This paper describes a trust overlay network developed in the OPAALS project to allow entities participating in digital ecosystems to share experience through the exchange of trust values and to leverage on this network to determine reputation based trustworthiness of unknown and initially untrusted entities. An overlay network is described together with sample algorithms and a discussion on implementation.

  10. QUANTIFIED COST-BALANCED ROUTING SCHEME FOR OVERLAY MULTICAST

    Institute of Scientific and Technical Information of China (English)

    Lu Jun; Ruan Qiuqi

    2006-01-01

    This paper focuses on the quantitative analysis issue of the routing metrics tradeoff problem, and presents a Quantified Cost-Balanced overlay multicast routing scheme (QCost-Balanced) to the metric tradeoff problem between overlay path delay and access bandwidth at Multicast Server Nodes (MSN) for real-time applications over Internet. Besides implementing a dynamic priority to MSNs by weighing the size of its service clients for better efficiency, QCost-Balanced tradeoffs these two metrics by a unified tradeoff metric based on quantitative analysis. Simulation experiments demonstrate that the scheme achieves a better tradeoff gain in both two metrics, and effective performance in metric quantitative control.

  11. Diffraction-based overlay for spacer patterning and double patterning technology

    Science.gov (United States)

    Lee, Byoung Hoon; Park, JeongSu; Lee, Jongsu; Park, Sarohan; Lim, ChangMoon; Yim, Dong-Gyu; Park, Sungki; Ryu, Chan-Ho; Morgan, Stephen; van de Schaar, Maurits; Fuchs, Andreas; Bhattacharyya, Kaustuve

    2011-03-01

    Overlay performance will be increasingly important for Spacer Patterning Technology (SPT) and Double Patterning Technology (DPT) as various Resolution Enhancement Techniques are employed to extend the resolution limits of lithography. Continuous shrinkage of devices makes overlay accuracy one of the most critical issues while overlay performance is completely dependent on exposure tool. Image Based Overlay (IBO) has been used as the mainstream metrology for overlay by the main memory IC companies, but IBO is not suitable for some critical layers due to the poor Tool Induced Shift (TIS) values. Hence new overlay metrology is required to improve the overlay measurement accuracy. Diffraction Based Overlay (DBO) is regarded to be an alternative metrology to IBO for more accurate measurements and reduction of reading errors. Good overlay performances of DBO have been reported in many articles. However applying DBO for SPT and DPT layers poses extra challenges for target design. New vernier designs are considered for different DPT and SPT schemes to meet overlay target in DBO system. In this paper, we optimize the design of the DBO target and the performance of DBO to meet the overlay specification of sub-3x nm devices which are using SPT and DPT processes. We show that the appropriate vernier design yields excellent overlay performance in residual and TIS. The paper also demonstrated the effects of vernier structure on overlay accuracy from SEM analysis.

  12. Recovery of Sublethally Injured Bacteria Using Selective Agar Overlays.

    Science.gov (United States)

    McKillip, John L.

    2001-01-01

    This experiment subjects bacteria in a food sample and an environmental sample to conditions of sublethal stress in order to assess the effectiveness of the agar overlay method to recover sublethally injured cells compared to direct plating onto the appropriate selective medium. (SAH)

  13. Incidental Learning of Geospatial Concepts across Grade Levels: Map Overlay

    Science.gov (United States)

    Battersby, Sarah E.; Golledge, Reginald G.; Marsh, Meredith J.

    2006-01-01

    In this paper, the authors evaluate map overlay, a concept central to geospatial thinking, to determine how it is naively and technically understood, as well as to identify when it is leaner innately. The evaluation is supported by results from studies at three grade levels to show the progression of incidentally learned geospatial knowledge as…

  14. 3D Align overlay verification using glass wafers

    NARCIS (Netherlands)

    Smeets, E.M.J.; Bijnen, F.C.G.; Slabbekoorn, J.; Van Zeijl, H.W.

    2004-01-01

    In the MEMS world, increasing attention is being given to 3D devices requiring dual-sided processing. This requires lithography tools that are able to align a wafer to both its back side as front side. Overlay describes how well front and back side layers are positioned with respect to each other. C

  15. Promoting Learning of Instructional Design via Overlay Design Tools

    Science.gov (United States)

    Carle, Andrew Jacob

    2012-01-01

    I begin by introducing Virtual Design Apprenticeship (VDA), a learning model--built on a solid foundation of education principles and theories--that promotes learning of design skills via overlay design tools. In VDA, when an individual needs to learn a new design skill or paradigm she is provided accessible, concrete examples that have been…

  16. Research on overlaying welding rod of high hardness maraging steel

    Institute of Scientific and Technical Information of China (English)

    PAN Yong-ming; CHEN Shao-wei

    2006-01-01

    The development of new maraging steel overlaying welding rod,which contains Co,Mo,W and V alloy,solved the problems of poor homogeneity of hardness and mechanical process, prolonged the service life of wear-resistant components and increased the productive efficiency of repairing,greatly benefiting the national economy.

  17. Crosslayer Survivability in Overlay-IP-WDM Networks

    Science.gov (United States)

    Pacharintanakul, Peera

    2010-01-01

    As the Internet moves towards a three-layer architecture consisting of overlay networks on top of the IP network layer on top of WDM-based physical networks, incorporating the interaction between and among network layers is crucial for efficient and effective implementation of survivability. This dissertation has four major foci as follows:…

  18. Mapping (USPTO) patent data using overlays to Google Maps

    NARCIS (Netherlands)

    Leydesdorff, L.; Bornmann, L.

    2012-01-01

    A technique is developed using patent information available online (at the U.S. Patent and Trademark Office) for the generation of Google Maps. The overlays indicate both the quantity and the quality of patents at the city level. This information is relevant for research questions in technology anal

  19. Time dependent viscoelastic rheological response of pure, modified and synthetic bituminous binders

    Science.gov (United States)

    Airey, G. D.; Grenfell, J. R. A.; Apeagyei, A.; Subhy, A.; Lo Presti, D.

    2016-08-01

    Bitumen is a viscoelastic material that exhibits both elastic and viscous components of response and displays both a temperature and time dependent relationship between applied stresses and resultant strains. In addition, as bitumen is responsible for the viscoelastic behaviour of all bituminous materials, it plays a dominant role in defining many of the aspects of asphalt road performance, such as strength and stiffness, permanent deformation and cracking. Although conventional bituminous materials perform satisfactorily in most highway pavement applications, there are situations that require the modification of the binder to enhance the properties of existing asphalt material. The best known form of modification is by means of polymer modification, traditionally used to improve the temperature and time susceptibility of bitumen. Tyre rubber modification is another form using recycled crumb tyre rubber to alter the properties of conventional bitumen. In addition, alternative binders (synthetic polymeric binders as well as renewable, environmental-friendly bio-binders) have entered the bitumen market over the last few years due to concerns over the continued availability of bitumen from current crudes and refinery processes. This paper provides a detailed rheological assessment, under both temperature and time regimes, of a range of conventional, modified and alternative binders in terms of the materials dynamic (oscillatory) viscoelastic response. The rheological results show the improved viscoelastic properties of polymer- and rubber-modified binders in terms of increased complex shear modulus and elastic response, particularly at high temperatures and low frequencies. The synthetic binders were found to demonstrate complex rheological behaviour relative to that seen for conventional bituminous binders.

  20. Characteristics of the benzene fraction of products resulting from the thermal destruction of bituminous petroleum

    Energy Technology Data Exchange (ETDEWEB)

    Kleev, A.M.; Margulis, B.Ya.; Martynov, A.A.; Vigdergauz, M.S.

    1979-01-01

    A description is given of a method for the chromatographic analysis of the 35 to 95/sup 0/C benzene feaction produced from the thermal destruction of bituminous petroleum. Aromatic, olefin, and paraffin-naphthene fractions were identified in the first stage of fluid chromatography with a fluorescent indicator. Gas chromatography was employed to undertake a detailed analysis of each fraction. The results of the analysis indicate that the use of a thermogas generator in the process of thermodestruction approximates the process of oxidative cracking. 11 references, 4 figures.

  1. Assessment of the Remaining Life of Bituminous Layers in Road Pavements

    Directory of Open Access Journals (Sweden)

    Kálmán Adorjányi

    2017-02-01

    Full Text Available In this paper, a mechanistic-empirical approach is presented for the assessment of bearing capacity condition of asphalt pavement layers by Falling Weight Deflectometer measurements and laboratory fatigue tests. The bearing capacity condition ratio was determined using past traffic data and the remaining fatigue life which was determined from multilayer pavement response model. The traffic growth rate was taken into account with finite arithmetic and geometric progressions. Fatigue resistance of layers’ bituminous materials was obtained with indirect tensile fatigue tests. Deduct curve of condition scores was derived with Weibull distribution.

  2. Adsorption of SO2 on bituminous coal char and activated carbon fiber prepared from phenol formaldehyde

    Science.gov (United States)

    DeBarr, Joseph A.; Lizzio, Anthony A.; Daley, Michael A.

    1996-01-01

    Carbon-based materials are used commercially to remove SO2 from coal combustion flue gases. Historically, these materials have consisted of granular activated carbons prepared from lignite or bituminous coal. Recent studies have reported that activated carbon fibers (ACFs) may have potential in this application due to their relatively high SO2 adsorption capacity. In this paper, a comparison of SO2 adsorption for both coal-based carbons and ACFs is presented, as well as ideas on carbon properties that may influence SO2 adsorption

  3. Hydrocarbon Generating Potential of Mineral—Bituminous Matrix in Source Rocks

    Institute of Scientific and Technical Information of China (English)

    陈建平; 黄第藩

    1998-01-01

    Mineral-bituminous matrix(MBM) makes up a major part of source rocks,but its potential in hydrocarbon generation is uncertain,Mineral and organic (Maceral and kerogen) compositions,organic maturity and fluorescence of MBM are studied based on source rock samples from eastern Jiuquan(Jiudong)Basin.The results show that MBM is dominated by inorganic minerals and among the small percentage of organic components those of secondary origins are predominant over the primary species.This strongly indicates that the significance of MBM in hydrocarbon generation is limited.

  4. Application of Interfacial Propagation and Kinking Crack Concept to ECC/Concrete Overlay Repair System

    Directory of Open Access Journals (Sweden)

    Yaw ChiaHwan

    2014-01-01

    Full Text Available Research on the application of ultraductile engineered cementitious composite (ECC as overlay in the repair of deteriorated concrete structures is performed in this paper. Also, interfacial crack kinking and trapping mechanism experimentally observed in ECC/concrete overlay repair system are described by comparison of toughness and energy release rate. The mechanism involves cycles of extension, kinking, and arrest of interfacial crack into the overlay. Experimental testing of overlay repair system reveals significant improvements in load carrying capacity and ductility over conventional concrete overlay. The commonly observed overlay system failure mode of delamination or spalling is eliminated when ECC is applied. These failure modes are suppressed when ECC is used as an ideal and durable candidate overlay repair material.

  5. A comparative study of overlay generation methods in bite mark analysis

    Directory of Open Access Journals (Sweden)

    Mihir Khatri

    2013-01-01

    Full Text Available Aim: To evaluate the best method of overlay generation out of the three methods, i.e., manual, photocopying, and computer assisted method. Materials and Methods: Impressions of maxillary and mandibular arches of 25 individuals participating in the study were made and dental study models were prepared. Overlay production was done by manual, photocopying, and computer assisted methods. Finally, the overlays obtained by each method were compared. Results: Kruskal Wallis ANOVA H test was used for the comparison of manual, photocopying, and computer assisted overlay generation methods. H value being highest in case of computer assisted overlays, thus, making it the best method of overlay generation out of the three methods. Conclusion: We conclude that the method of computer assisted overlay generation is the best among the three methods used in our study.

  6. Virtual Private Overlays: Secure Group Commounication in NAT-Constrained Environments

    CERN Document Server

    Wolinsky, David Isaac; Choi, Tae Woong; Boykin, P Oscar; Figueiredo, Renato

    2010-01-01

    Structured P2P overlays provide a framework for building distributed applications that are self-configuring, scalable, and resilient to node failures. Such systems have been successfully adopted in large-scale Internet services such as content delivery networks and file sharing; however, widespread adoption in small/medium scales has been limited due in part to security concerns and difficulty bootstrapping in NAT-constrained environments. Nonetheless, P2P systems can be designed to provide guaranteed lookup times, NAT traversal, point-to-point overlay security, and distributed data stores. In this paper we propose a novel way of creating overlays that are both secure and private and a method to bootstrap them using a public overlay. Private overlay nodes use the public overlay's distributed data store to discover each other, and the public overlay's connections to assist with NAT hole punching and as relays providing STUN and TURN NAT traversal techniques. The security framework utilizes groups, which are cr...

  7. Performance of Superposition Coded Broadcast/Unicast Service Overlay System

    Science.gov (United States)

    Yoon, Seokhyun; Kim, Donghee

    The system level performance of a superposition coded broadcast/unicast service overlay system is considered. Cellular network for unicast service only is considered as interference limited system, where increasing the transmission power does not help improve the network throughput especially when the frequency reuse factor is close to 1. In such cases, the amount of power that does not contribute to improving the throughput can be considered as “unused.” This situation motivates us to use the unused power for broadcast services, which can be efficiently provided in OFDM based single frequency networks as in digital multimedia broadcast systems. In this paper, we investigate the performance of such a broadcast/unicast overlay system in which a single frequency broadcast service is superimposed over a unicast cellular service. Alternative service multiplexing using FDM/TDM is also considered for comparison.

  8. Rutting Resistance of Asphalt Overlay with Multilayer Wheel Tracking Test

    Institute of Scientific and Technical Information of China (English)

    LIAO Weidong; CHEN Zheng; WU Shaopeng; MO Liantong; LIU Gang

    2006-01-01

    The rutting resistance of multilayer asphalt overlay was researched by using laboratory wheel tracking test. The effects of loading level and test temperature on rutting resistance of asphalt overlay structure were evaluated by means of multilayer specimens .In comparison with multilayer tests, standard specimens of various layers were also conducted to evaluate the rutting resistance. Experimental results indicated that the test temperature and applied load have a significant effect on rutting resistance of asphalt concrete. Higher test temperature and heavier applied load resulted in higher rut depths. In addition, the mutilayer wheel tracking test has been demonstrated to be a more reasonable solution in evaluation on rutting resistance of asphatt pavement structure beasuse it reflects the cumulative permanent deformation in all of asphalt layers.

  9. CodedStream: live media streaming with overlay coded multicast

    Science.gov (United States)

    Guo, Jiang; Zhu, Ying; Li, Baochun

    2003-12-01

    Multicasting is a natural paradigm for streaming live multimedia to multiple end receivers. Since IP multicast is not widely deployed, many application-layer multicast protocols have been proposed. However, all of these schemes focus on the construction of multicast trees, where a relatively small number of links carry the multicast streaming load, while the capacity of most of the other links in the overlay network remain unused. In this paper, we propose CodedStream, a high-bandwidth live media distribution system based on end-system overlay multicast. In CodedStream, we construct a k-redundant multicast graph (a directed acyclic graph) as the multicast topology, on which network coding is applied to work around bottlenecks. Simulation results have shown that the combination of k-redundant multicast graph and network coding may indeed bring significant benefits with respect to improving the quality of live media at the end receivers.

  10. On-demand Overlay Networks for Large Scientific Data Transfers

    Energy Technology Data Exchange (ETDEWEB)

    Ramakrishnan, Lavanya [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Guok, Chin [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Jackson, Keith [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Kissel, Ezra [Univ. of Delaware, Newark, DE (United States); Swany, D. Martin [Univ. of Delaware, Newark, DE (United States); Agarwal, Deborah [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2009-10-12

    Large scale scientific data transfers are central to scientific processes. Data from large experimental facilities have to be moved to local institutions for analysis or often data needs to be moved between local clusters and large supercomputing centers. In this paper, we propose and evaluate a network overlay architecture to enable highthroughput, on-demand, coordinated data transfers over wide-area networks. Our work leverages Phoebus and On-demand Secure Circuits and AdvanceReservation System (OSCARS) to provide high performance wide-area network connections. OSCARS enables dynamic provisioning of network paths with guaranteed bandwidth and Phoebus enables the coordination and effective utilization of the OSCARS network paths. Our evaluation shows that this approach leads to improved end-to-end data transfer throughput with minimal overheads. The achievedthroughput using our overlay was limited only by the ability of the end hosts to sink the data.

  11. Ion beam mixing of titanium overlayers with hydroxyapaptite substrates

    Energy Technology Data Exchange (ETDEWEB)

    Levine, T.E. [Cornell Univ., Ithaca, NY (United States). Dept. of Materials Science and Engineering; Nastasi, M. [Los Alamos National Lab., NM (United States); Alford, T.L.; Suchicital, C.; Russell, S.; Luptak, K.; Pizziconi, V.; Mayer, J.W. [Arizona State Univ., Tempe, AZ (United States)

    1995-01-01

    The mixing of titanium overlayers with hydroxyapatite (HA) substrates via ion irradiation has been demonstrated. Analysis via secondary ion mass spectroscopy (SIMS) indicates an interfacial broadening of titanium and calcium of the implanted sample compared to that of the unimplanted sample. Attendant to the observed ion beam mixing of titanium into the HA, the oxygen signal of the titanium overlayer increases as a result of ion irradiation. It is supposed that this change is evident of diffusion through the metal layer and possibly from titania formation at the free surface and perovskite formation at the film/substrate interface. This possibility is consistent with thermodynamic predictions. Additionally, the force required to separate the film from the substrate increased as a result of ion irradiation, validating the continued study of ion beam processing of Ti/HA systems towards the improvement of long term fixation of implant devices.

  12. Modeling the dynamical interaction between epidemics on overlay networks

    CERN Document Server

    Marceau, Vincent; Hébert-Dufresne, Laurent; Allard, Antoine; Dubé, Louis J

    2011-01-01

    Epidemics seldom occur as isolated phenomena. Typically, two or more viral agents spread within the same host population and may interact dynamically with each other. We present a general model where two viral agents interact via an immunity mechanism as they propagate simultaneously on two networks connecting the same set of nodes. Exploiting a correspondence between the propagation dynamics and a dynamical process performing progressive network generation, we develop an analytic approach that accurately captures the dynamical interaction between epidemics on overlay networks. The formalism allows for overlay networks with arbitrary joint degree distribution and overlap. To illustrate the versatility of our approach, we consider a hypothetical delayed intervention scenario in which an immunizing agent is disseminated in a host population to hinder the propagation of an undesirable agent (e.g. the spread of preventive information in the context of an emerging infectious disease).

  13. Synergistic effect on thermal behavior during co-pyrolysis of lignocellulosic biomass model components blend with bituminous coal.

    Science.gov (United States)

    Wu, Zhiqiang; Wang, Shuzhong; Zhao, Jun; Chen, Lin; Meng, Haiyu

    2014-10-01

    Co-thermochemical conversion of lignocellulosic biomass and coal has been investigated as an effective way to reduce the carbon footprint. Successful evaluating on thermal behavior of the co-pyrolysis is prerequisite for predicting performance and optimizing efficiency of this process. In this paper, pyrolysis and kinetics characteristics of three kinds of lignocellulosic biomass model components (cellulose, hemicellulose, and lignin) blended with a kind of Chinese bituminous coal were explored by thermogravimetric analyzer and Kissinger-Akahira-Sunose method. The results indicated that the addition of model compounds had different synergistic effects on thermal behavior of the bituminous coal. The cellulose showed positive synergistic effects on the thermal decomposition of the coal bituminous coal with lower char yield than calculated value. For hemicellulose and lignin, whether positive or negative synergistic was related to the mixed ratio and temperature range. The distribution of the average activation energy values for the mixtures showed nonadditivity performance.

  14. Mapping (USPTO) Patent Data using Overlays to Google Maps

    OpenAIRE

    Leydesdorff, Loet; Bornmann, Lutz

    2011-01-01

    A technique is developed using patent information available online (at the US Patent and Trademark Office) for the generation of Google Maps. The overlays indicate both the quantity and quality of patents at the city level. This information is relevant for research questions in technology analysis, innovation studies and evolutionary economics, as well as economic geography. The resulting maps can also be relevant for technological innovation policies and R&D management, because the US market...

  15. Perceived effects of coloured overlays on reading material in persons with albinism

    Directory of Open Access Journals (Sweden)

    N. T. Makgaba

    2008-01-01

    Full Text Available Persons with albinism often complain of glare when reading. They may therefore benefit from coloured filter overlays just as they benefit from tinted lenses. The purpose of this study was to assess the effectof coloured overlays on print perception in persons with oculocutaneous albinism (OCA.   Fifty subjects were included in this study, their ages ranged from 12 to 31 years with a mean of 16.12 years (SD = ± 4.56 years.  Following refraction and subsequent compensation for refractive errors, subjective perception of print was examined with the subject looking at the Wilkins® reading rate test chart with and without colored filter overlay/s.  The subjects were asked to respond to questions previously used in a questionnaire by Wilkins (2001. The percentage frequencies of positive (beneficial responses were used to decide whether or not a particular overlay would enhance reading performance.  McNemar’s test was used to establish significant differences between responses to questions without and with overlays. All single overlays gave greater percentages of positive responses (92.0-97.2% than without overlay (85.2%.  The single overlay that provided the highest positive responses was blue (97.2% and the least was purple (92.0%. All double overlays, except grey/grey (82.0% gave greater positive responses than without overlay (85.2%. Aqua/blue gave the greatest positive responses (possible benefits (97.2%, followed by rose/rose (96.8%.  Comparing the responses without overlay with single and double overlays, the difference in responses to the five questions was only significant (p < 0.05 with regard to brightness of the surface. The results suggest that overlays provided a more glare-free reading surface than without an overlay. It was, therefore concluded that the best advantage of the coloured overlays was in glare reduction.  Although this study showed that there were more subjects who preferred single blue and aqua/blue double

  16. Scalable Overlay Multicasting in Mobile Ad Hoc Networks (SOM

    Directory of Open Access Journals (Sweden)

    Pariza Kamboj

    2010-10-01

    Full Text Available Many crucial applications of MANETs like the battlefield, conference and disaster recovery defines the needs for group communications either one-to-many or many-to-many form. Multicast plays an important role in bandwidth scarce multihop mobile ad hoc networks comprise of limited battery power mobile nodes. Multicast protocols in MANETs generate many controls overhead for maintenance of multicast routingstructures due to frequent changes of network topology. Bigger multicast tables for the maintenance of network structures resultsin inefficient consumption of bandwidth of wireless links andbattery power of anemic mobile nodes, which in turn, pose thescalability problems as the network size is scaled up. However,many MANET applications demands scalability from time to time. Multicasting for MANETs, therefore, needs to reduce the state maintenance. As a remedy to these shortcomings, this paper roposes an overlay multicast protocol on application layer. In the proposed protocol titled “Scalable Overlay Multicasting in Mobile Ad Hoc Networks (SOM” the network nodes construct overlay hierarchical framework to reduce the protocols states and constrain their distribution within limited scope. Based on zone around each node, it constructs a virtual structure at application layer mapped with the physical topology at network layer, thus formed two levels of hierarchy. The concept of two level hierarchies reduces the protocol state maintenance and hence supports the vertical scalability. Protocol depends on the location information obtained using a distributed location service, which effectively reduces the overhead for route searching and updating the source based multicast tree.

  17. Ground truth data generation for skull-face overlay.

    Science.gov (United States)

    Ibáñez, O; Cavalli, F; Campomanes-Álvarez, B R; Campomanes-Álvarez, C; Valsecchi, A; Huete, M I

    2015-05-01

    Objective and unbiased validation studies over a significant number of cases are required to get a more solid picture on craniofacial superimposition reliability. It will not be possible to compare the performance of existing and upcoming methods for craniofacial superimposition without a common forensic database available for the research community. Skull-face overlay is a key task within craniofacial superimposition that has a direct influence on the subsequent task devoted to evaluate the skull-face relationships. In this work, we present the procedure to create for the first time such a dataset. We have also created a database with 19 skull-face overlay cases for which we are trying to overcome legal issues that allow us to make it public. The quantitative analysis made in the segmentation and registration stages, together with the visual assessment of the 19 face-to-face overlays, allows us to conclude that the results can be considered as a gold standard. With such a ground truth dataset, a new horizon is opened for the development of new automatic methods whose performance could be now objectively measured and compared against previous and future proposals. Additionally, other uses are expected to be explored to better understand the visual evaluation process of craniofacial relationships in craniofacial identification. It could be very useful also as a starting point for further studies on the prediction of the resulting facial morphology after corrective or reconstructive interventionism in maxillofacial surgery.

  18. Diffusion Barriers to Increase the Oxidative Life of Overlay Coatings

    Science.gov (United States)

    Nesbitt, James A.; Lei, Jih-Fen

    1999-01-01

    Currently, most blades and vanes in the hottest section of aero gas turbine engines require some type of coating for oxidation protection. Newly developed single crystal superalloys have the mechanical potential to operate at increasingly higher component temperatures. However, at these elevated temperatures, coating/substrate interdiffusion can shorten the protective life of the coating. Diffusion barriers between overlay coatings and substrates are being examined to extend the protective life of the coating. A previously- developed finite-difference diffusion model has been modified to predict the oxidative life enhancement due to use of a diffusion barrier. The original diffusion model, designated COSIM, simulates Al diffusion in the coating to the growing oxide scale as well as Al diffusion into the substrate. The COSIM model incorporates an oxide growth and spalling model to provide the rate of Al consumption during cyclic oxidation. Coating failure is predicted when the Al concentration at the coating surface drops to a defined critical level. The modified COSIM model predicts the oxidative life of an overlay coating when a diffusion barrier is present eliminating diffusion of Al from the coating into the substrate. Both the original and the modified diffusion models have been used to predict the effectiveness of a diffusion barrier in extending the protective life of a NiCrAl overlay coating undergoing cyclic oxidation at 1100 C.

  19. Low SO2 emission from CFB co-firing MSW and bituminous

    Institute of Scientific and Technical Information of China (English)

    LU Qing-gang; LI Zhi-wei; NA Yong-jie; BAO Shao-lin; SUN Yun-kai; HE Jun

    2004-01-01

    Influence of co-firing rate on SO2 emission from co-firing municipal solid waste(MSW) and bituminous containing high amount of sulfur(1.79%) was studied in a 0.15 MWt circulating fluidized bed(CFB). The temperature selected is 1123 K, typical for MSW incineration using CFB. The particle concentration in the dilution zone of the furnace, the alkali metal concentration and sulfate concentration in the recirculating ash and fly ash, and flue gas composition were determined. The results showed that the addition of MSW leads to a significant decrease in SO2 emission. Concentration of SO2 in flue gas decreased to 0 with the co-firing rate greater than 51%. This reduction in SO2 emission is attributed both to the high particle concentration in the dilution zone of the furnace, the high content of alkali metals in the bed material, and to the comparatively high concentration of HCl in flue gas during co-firing of MSW and bituminous.

  20. GC/MS Analysis of Fractional Extraction of Fusain from Tongting Bituminous Coal in CS2

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Fusain from Tongting (Huaibei, Anhui Province) bituminous (FTTB) coal was fractionally extracted using Soxhlet extractor with CS2. Then the extracts were analyzed with GC/MS. Comparison of experimental data between FTTB coal and clarain from Tongting bituminous (CTTB) coal was carried out. The results show that the kinds of small molecule components detected by GC/MS of FTTB are less than those of CTTB. Long-chain alkanes exist mostly in the extracts of fusain. Macromolecular networks are predominant in the FTTB coal mainly composed of inertinite in the coal petrography. The size of micropores in the FTTB coal is relatively small, and the development of micropores is relatively low. Thus the content of aromatic compounds with affinity for micropores is relative low in FTTB, while the content of long-chain alkanes with affinity for macromolecule networks is relatively high. Sub-components in exinite determine the distribution of long-chain alkanes extracted in the last stage. Odd-numbered carbon distribution appears when resin is most in exinite, while high carbon alkane distribution appears when exinite is dominant in cutinite. Small aromatic molecules are firstly packed in micropores, and exist in a free state after micropores are saturated.

  1. THE HISTORY OF EXPLORATION AND EXPLOITATION OF BITUMINOUS AND KEROGENOUS DEPOSITS IN CROATIA

    Directory of Open Access Journals (Sweden)

    Berislav Šebečić

    1995-12-01

    Full Text Available It is assumed thal the first known sedimens of natural bitumen or asphalt in coastal Croatia were exploited as the early moddle ages. Yet authenticated written documents about Vinišće near Trogir derive from no earlier than 1628, about Vrgorac/Paklina from only 1753. By the end of the 18th century, many deposits were discovered in Dalmatia, but it was Škrip on the Island of Brač and Suhi Dolac that were important. The earliest known deposits and occurrences of kerogenous rocks, or bituminous or oil shales, are mentioned as stone or fossil coal in Sovinjak, in the upper course of the River Mirna, and in Rebići in Istria; near Sinj, Slivno not far from the River Neretva, Mirta and near Nerežišće on the Island uf Brač. All if these were well known and described in 1804, while Sovinjak was mentioned in the 16th century. In the article, some of new information derived from mining and geological research into bituminous and kerogenous sediments and deposits are provided (the paper is published in Croatian.

  2. Biomarker geochemistry of bituminous shale sequence and crude oil in the Ereǧli-Bor Basin (Konya-Niǧde), Central Anatolia, Turkey

    Science.gov (United States)

    Kara-Gulbay, Reyhan; Erdogan, Mert; Korkmaz, Sadettin; Kadinkiz, Gökhan

    2016-04-01

    In the Ereǧli-Bor Basin (Konya-Niǧde), Central Anatolia, bituminous shale sequence with thickness ranging between 72 and 160 m occurs in lacustrine deposits of Upper Miocene-Pliocene age. The live oil has also been observed in this bituminous shale sequence. Rock-Eval/TOC, GC and GC-MS analyses were conducted on selected bituminous shale samples from four borehole (key-12/1, key-12/2, key-12/3 key-12/4) and one crude oil sample from a borehole (key-12/2) in the basin. In this study, organic matter type, maturity and depositional environment of bituminous shale are evaluated and the origin of crude oil is determined by the bituminous shale-crude oil correlation. The total organic carbon (TOC) values of the bituminous shale samples range from 1.21-13.98 wt% with an average TOC value of 4.75wt%. The bituminous shale sequence is characterized by high HI (127-662 mg HC/g TOC) and low OI (7-50 mgCO2/TOC). Tmax varies from 332-419ᵒC. Very low Pr/Ph ratios of bituminous shale (0.09-0.22) are indicative of anoxic depositional conditions. C27 is dominate sterane for bituminous shale and crude oil samples with C27>C29>C28. Normal steranes are more dominant compare to iso- and diasteranes. Ouite high sterane/hopane ratios (1.14-2.70) indicate dominant algal organic matter input for bituminous shale and source rock of crude oil. C31R/hopane ratio for bituminous shale and crude oil samples are very low (0.09-0.13) and these ratio show a lacustrine depositional envirronment for bituminous shale and source rock of crude oil. Sterane and terpane distributions of bituminous shale and crude oil are very similar. A very good correlation in terms of biomarker between bituminous shale and crude oil samples indicate that source rock of crude oil is bituminous shale. The 22S/(22R + 22S) C32 homohopane ratios of bituminous shale and crude oil samples are found to be 0.56 and 0.61, indicating that homohopane isomerization has attained equilibrium and bituminous shale and crude oil are

  3. Mechanical properties of hot bituminous mixes manufactured with recycled aggregate of Silestone® waste

    Directory of Open Access Journals (Sweden)

    Rubio, M. C.

    2011-03-01

    Full Text Available This article presents the results of a research project which analyzes the viability of incorporating waste material from decorative quartz solid surfacing in the manufacture of hot bituminous mixes. For this purpose, various bituminous mixes were manufactured with waste aggregate in different percentage. A set of tests were carried out that permitted the characterization of the mechanical behavior of these mixes. The results of these tests were similar to the results obtained when conventional mixes made from virgin quarry aggregate were tested. The results for moisture sensitivity as well as for wheel track rutting on mixes showed the optimal performance of this waste material even under very demanding traffic conditions. Laboratory studies showed that the use of this waste material in the manufacture of bituminous mixes is technically viable and can provide high-quality recycled aggregates at a very low cost, which can be used in the pavement of road.

    Este artículo muestra los resultados de un proyecto de investigación que tiene por objeto analizar la viabilidad de incorporación de residuos procedentes de piedra decorativa en la fabricación de mezclas bituminosas en caliente. Para ello se fabricaron mezclas con áridos reciclados de residuos procedentes de piedra decorativa en distintos porcentajes, realizando un conjunto de ensayos que posibilitaron caracterizar el comportamiento mecánico de dichas mezclas. Los resultados obtenidos fueron similares a los de las mezclas convencionales fabricadas con áridos vírgenes procedentes de cantera. Los valores de resistencia conservada ante la acción del agua y deformación en pista, pusieron de manifiesto la aptitud del residuo incluso ante las condiciones de tráfico más exigentes. Los trabajos realizados en el laboratorio indican que la utilización del residuo en la fabricación de mezclas bituminosas es técnicamente viable, pudiendo obtenerse áridos reciclados de gran calidad y

  4. Osmosis-induced swelling of Eurobitum bituminized radioactive waste in constant total stress conditions

    Science.gov (United States)

    Valcke, E.; Marien, A.; Smets, S.; Li, X.; Mokni, N.; Olivella, S.; Sillen, X.

    2010-11-01

    In geological disposal conditions, contact of Eurobitum bituminized radioactive waste, which contains high amounts of the hygroscopic and highly soluble NaNO 3, with groundwater will result in water uptake and swelling of the waste, and in subsequent leaching of the embedded NaNO 3 and radionuclides. The swelling of and the NaNO 3 leaching from non-radioactive Eurobitum samples, comprised between two stainless steel filters and in contact with 0.1 M KOH, was studied in restricted (semi-confined) swelling conditions, i.e. under a constant total stress, or counterpressure, of 2.2, 3.3, or 4.4 MPa ( i.e. oedometer conditions). Four tests were stopped after hydration times between 800 and 1500 days, and the samples were analyzed by micro-focus X-ray Computer Tomography (μCT) and by Environmental Scanning Electron Microscopy (ESEM). The complete set of data enabled a consistent interpretation of the observations and lead to an improved understanding of the phenomenology of the water uptake, swelling, and NaNO 3 leaching in restricted swelling conditions. Under the studied conditions, the bituminous matrix surrounding the NaNO 3 crystals and pores with NaNO 3 solution behaved as a highly efficient semi-permeable membrane, i.e. osmotic processes occurred. In the main part of the leached layers, a high average NaNO 3 concentration and related to this a high osmotic pressure prevailed, explaining why in the studied range the swelling was not measurably affected by the counterpressure. At the interface with the stainless steel filters, a low permeable re-compressed bitumen layer was formed, contributing to the slow release of NaNO 3 compared to the water uptake rate. A fully coupled Chemo-Hydro-Mechanical (CHM) constitutive model has been developed that integrates the key processes involved and that reproduces satisfactorily the results; this is presented in another work. Combination of the experimental and the modelling study allow to conclude that under semi

  5. Development prospects for Bazhenov formation bituminous claystones in the southeast of the West Siberian Plate (Tomsk Region)

    Science.gov (United States)

    Belozerov, V. B.; Baranov, V. E.; Dmitriev, A. Y.

    2015-02-01

    The article considers the use of time-tested bituminous shale development technologies in the southeast of the West Siberian Plate (Tomsk Region). A research target is the bituminous claystones of the Bazhenov formation. The Bazhenov formation was divided into stratigraphic units, and the sequence of forming these units within the territory under study was restored on the basis of the peculiarities of the Bazhenov formation section structure with gamma-ray logging data. The joint analysis of logs (gamma-ray logging, resistivity logging, SP logging, neutron gamma-ray logging, induction logging) and core data revealed the wide development of carbonatization processes in the lower stratigraphic units of the Bazhenov formation, whereas the upper, most bituminous units do not have the signs of carbonatization. It is a favorable factor for using the existing technologies of producing hydrocarbons from analogous sedimentary deposits. Considering the degree of lithological disconnection of an oilbearing object from adjacent reservoir formations allows making a conclusion that the application of the existing technologies for developing bituminous claystones can be implemented only in the insignificant territory of the area under study where the Bazhenov formation overlies Georgiev formation claystones being over 8 meters thick. To develop the oil and gas potential of the Bazhenov formation in other territories, there will be a need for new technologies that allow forming a fracture-cavernous matrix in a carbonate rock.

  6. Organic Material and Trace Elements of Bituminous Rocks in the Ozank(o)y Field, Ankara, Turkey

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Bituminous rocks in the Ozank(o)y (Ankara) field are different from those of the Paleocenecontent of organic material-rich rocks in the Ozank(o)y (Ankara) field is 3.66-40.72 % wt averaging 14.34%. The dominant organic materials are algae/amorphous accompanied by minor amount of herbaceous material (The dominant kerogen type is Type-Ⅰ with a limited amount of Type-Ⅱ kerogen.).The bituminous rocks in the Ozank(o)y field are enriched in heavy metals such as Ni, Mn, As and Cr. In comparison with the average enrichment values of elements, Ni, Mn, As and Cr in bituminous shales of the Ozank(o)y field are as about 4.38, 14.93, 10.90 and 5.58 times as average values. The average concentrations of these heavy metals are also as high as 215 × 10-6, 828 × 10-6, 58.54 × 10-6, and 148× 10-6 respectively. In addition, sorption properties of clay and organic materials are also important for metal enrichments in the bituminous shales.

  7. Evaluation of parameters affecting reflection cracking in geogrid-reinforced overlay

    Institute of Scientific and Technical Information of China (English)

    Shahab Fallah; Ali Khodaii

    2015-01-01

    The influence of the most important parameters on the service life of reinforced asphalt overlay with geogrid materials in bending mode was examined by employing the Taguchi method and analysis of variance techniques. The objectives of this experiment was to investigate the effects of grid stiffness, tensile strength, coating type, amount of tack coat, overlay thickness, crack width and stiffnesses of asphalt overlay and existing asphalt concrete on propagation of the reflection cracking. Results indicate that the stiffnesses of cracked layer and overlay are the main significant factors that can directly improve the service life of an overlay against the reflection cracking. Generally, glass grid is more effective in reinforced overlay than polyester grid. Effect of crack width of the existing layer is significant when its magnitude increases from 6 to 9 mm.

  8. OMAN - A Management Architecture for P2P Service Overlay Networks

    OpenAIRE

    Fiorese, Adriano; Simões, Paulo; Boavida, Fernando

    2010-01-01

    International audience; In a world where networking services are increasingly being provided by service overlay networks, management of these services at overlay level is becoming crucially important. This paper presents an architecture for services management in P2P Service Overlay Networks (SON). The architecture, named OMAN, takes into account the formation of the P2P SON comprising several different service providers belonging to several different network domains. It uses P2P mechanisms t...

  9. Ductile film delamination from compliant substrates using hard overlayers

    Science.gov (United States)

    Cordill, M.J.; Marx, V.M.; Kirchlechner, C.

    2014-01-01

    Flexible electronic devices call for copper and gold metal films to adhere well to polymer substrates. Measuring the interfacial adhesion of these material systems is often challenging, requiring the formulation of different techniques and models. Presented here is a strategy to induce well defined areas of delamination to measure the adhesion of copper films on polyimide substrates. The technique utilizes a stressed overlayer and tensile straining to cause buckle formation. The described method allows one to examine the effects of thin adhesion layers used to improve the adhesion of flexible systems. PMID:25641995

  10. Autologous adventitial overlay method reinforces anastomoses in aortic surgery.

    Science.gov (United States)

    Minato, Naoki; Okada, Takayuki; Sumida, Tomohiko; Watanabe, Kenichi; Maruyama, Takahiro; Kusunose, Takashi

    2014-05-01

    In this study, we present an inexpensive and effective method for providing a secure and hemostatic anastomosis using autologous adventitia obtained from a dissected or aneurysmal wall. The resected aortic wall is separated between the adventitia and media, and a soft, 2 × 10-cm adventitial strip is overlaid to cover the anastomotic margin. A graft is sutured to the aortic stump. This autologous adventitial overlay method can inexpensively and strongly reinforce the anastomosis during aortic surgery for dissection or aneurysm and will contribute to anastomotic hemostasis and long-term stability.

  11. Using overlay network architectures for scalable video distribution

    Science.gov (United States)

    Patrikakis, Charalampos Z.; Despotopoulos, Yannis; Fafali, Paraskevi; Cha, Jihun; Kim, Kyuheon

    2004-11-01

    Within the last years, the enormous growth of Internet based communication as well as the rapid increase of available processing power has lead to the widespread use of multimedia streaming as a means to convey information. This work aims at providing an open architecture designed to support scalable streaming to a large number of clients using application layer multicast. The architecture is based on media relay nodes that can be deployed transparently to any existing media distribution scheme, which can support media streamed using the RTP and RTSP protocols. The architecture is based on overlay networks at application level, featuring rate adaptation mechanisms for responding to network congestion.

  12. Opportunistic transmitter selection for selfless overlay cognitive radios

    KAUST Repository

    Shaqfeh, Mohammad

    2013-11-01

    We propose an opportunistic strategy to grant channel access to the primary and secondary transmitters in causal selfless overlay cognitive radios over block-fading channels. The secondary transmitter helps the primary transmitter by relaying the primary messages opportunistically, aided by a buffer to store the primary messages temporarily. The optimal channel-aware transmitter- selection strategy is the solution of the maximization of the average secondary rate under the average primary rate requirement and the buffer stability constraints. Numerical results demonstrate the gains of the proposed opportunistic selection strategy. © 2013 IEEE.

  13. Employing Multicast in P2P Overlay Networks

    Science.gov (United States)

    Kolberg, Mario

    The work on multicast has evolved from bottom IP layer multicast to Application Layer Multicast. While there are issues with the dep-loyment of IP layer multicast, it outperforms Application Layer Multicast. However, the latter has the advantage of an easier dep-loyment. Furthermore, as will be illustrated later in this Chapter, IP layer multicast has the potential to make parallel overlay operations more efficient. Application Layer Multicast is primarily used to send application specific messages/data to a number of nodes.

  14. Combustion characteristics and arsenic retention during co-combustion of agricultural biomass and bituminous coal.

    Science.gov (United States)

    Zhou, Chuncai; Liu, Guijian; Wang, Xudong; Qi, Cuicui; Hu, Yunhu

    2016-08-01

    A combination of thermogravimetric analysis (TG) and laboratory-scale circulated fluidized bed combustion experiment was conducted to investigate the thermochemical, kinetic and arsenic retention behavior during co-combustion bituminous coal with typical agricultural biomass. Results shown that ignition performance and thermal reactivity of coal could be enhanced by adding biomass in suitable proportion. Arsenic was enriched in fly ash and associated with fine particles during combustion of coal/biomass blends. The emission of arsenic decreased with increasing proportion of biomass in blends. The retention of arsenic may be attributed to the interaction between arsenic and fly ash components. The positive correlation between calcium content and arsenic concentration in ash suggesting that the arsenic-calcium interaction may be regarded as the primary mechanism for arsenic retention.

  15. Physical properties of solid fuel briquettes from bituminous coal waste and biomass

    Institute of Scientific and Technical Information of China (English)

    ZARRINGHALAM-MOGHADDAM A; GHOLIPOUR-ZANJANI N; DOROSTIS; VAEZ M

    2011-01-01

    Biomass and bituminous coal fines from four different coalfields were used to produce fuel briquettes.Two physical properties of briquettes,water resistance index and compressive strength were analyzed.The influence of type and quantity of biomass on physical properties was also studied.The results reveal that depending on the mineral content of the coal,the physical properties of the briquettes differ noticeably.The comparison of briquettes with and without biomass showed that the presence of the beet pulp increased CS in all types of coal samples.Samples containing beet pulp had better physical properties than sawdust.Mezino Ⅱ coal briquettes had highest CS and WRI than the other ones.Calorific value of biomass/Mezino Ⅱ coal briquettes was lessened in comparison with raw coal,but it remained in an acceptable range.

  16. STUDY ON EVOLUTION REGULARITIES AND ABSORPTION CHARACTERISTICS OF SULFIDE DURING BITUMINOUS BRIQUETTE HORIZONTAL COMBUSTION

    Institute of Scientific and Technical Information of China (English)

    路春美; 王永征

    1999-01-01

    This paper discusses the evolution regularity and the absorption characters of sulfide for bituminous briquette burned in a horizontal burning furnace. The evolution rate of sulphur is affected by some factors, such as the sulphur content in the burning coal, burning time and the meane excess air coefficient in the furnace. With processing the experimental result, the calculation related expression has been obtained to predict the evolution rate of sulfide. The sulphur absorption efficiency of briquette is affected by the factors such as the character of the sulphur sorbent, the type of the coal and the operating parameters. "By means of appropriately adjusting the calciumsulphur mole ratio, the mean excess air coefficient and the time-interval between pushing two layer briquettes, a high sulphur absorption efficiency (>74%) can be obtained.

  17. Biological markers in bitumens and pyrolyzates of Upper Cretaceous bituminous chalks from the Ghareb Formation (Israel)

    Science.gov (United States)

    Rullkötter, Jürgen; Aizenshtat, Zeev; Spiro, Baruch

    1984-01-01

    The sterane and triterpane distributions of three bituminous chalks from the Upper Cretaceous Ghareb Formation (Israel) were investigated both in the original extractable bitumens and in extracts obtained after pyrolysis of whole rock and isolated kerogen samples at 450°C. Pyrolysis was performed in a closed system under hydrous (whole rock) and anhydrous conditions (isolated kerogens). The carbon number distributions of steranes and triterpanes differ significantly between original bitumen and pyrolyzates. Unlike the bitumens in which diasteranes were not detected, the anhydrous pyrolyzates contain small amounts of diasteranes. The presence of water during pyrolysis leads to an increase of sterane isomerization, the abundant formation of diasteranes and an increase of the 18α( H)- trisnorneohopane/17α( H)- trisnorhopane ratio. Sterane isomerization maturation parameters show a closer match between original bitumen and pyrolyzates after pyrolysis in a closed system when compared with an open system.

  18. Distribution of inorganic and organic substances in the hydrocyclone separated Slovak sub-bituminous coal

    Energy Technology Data Exchange (ETDEWEB)

    Anton Zubrik; Slavomir Hredzak; Ludmila Turcaniova; Michal Lovas; Ingo Bergmann; Klaus Dieter Becker; Maria Lukcova; Vladimir Sepelak [Slovak Academy of Sciences, Kosice (Slovakia). Institute of Geotechnics

    2010-08-15

    A low-rank Slovak sub-bituminous coal from the Handlova deposit was physically treated by washing in a water-only cyclone with the goal to find the separation effect for inorganic (mainly Fe-bearing minerals) and organic substances (humic acids, diterpanes). A high-quality coal product with the ash content in the dry matter of 9.02% and carbon content of C{sup d} = 68.12% at a mass yield of 29.51% was obtained using the water-only cyclone processing. At first, the physically treated coal samples were detailed characterized by XRD, {sup 57}Fe Moessbauer spectroscopy, FT-IR and HR-TEM. In addition to non-crystalline organic coal components, inorganic compounds belonging to silicate minerals (kaolinite, muscovite and quartz) as well as to Fe-bearing sulphide minerals (pyrite) were identified in the sub-bituminous coal by XRD. {sup 57}Fe Moessbauer spectroscopy detected the presence of iron carbonate (siderite), iron-containing clay mineral and two sulphur-containing minerals (pyrite, jarosite) in the untreated coal. On the other hand, only one Fe-bearing mineral, (pyrite) was found in the washed coal. Effect of the physical separation is also demonstrated in FT-IR spectra, where the peak at 1040 cm{sup -1} representing the silicate component in the untreated sample is not detectable in the washed coal sample. Presence of extractive organic substances, i.e. humic acids and tetracyclic diterpane (16a(H)-phyllocladane), in the hydrocyclone products is also evidenced. It was confirmed that the isolated diterpenoic compound is attendant in the washed product with the lowest ash content and it is assimilated with the organic part of coal. Surprisingly, humic acids were found in the highest concentration in the slurry that has the highest content of ash (63.14%). 54 refs., 8 figs., 5 tabs.

  19. Using proximate analysis to characterize airborne dust generation from bituminous coals

    Energy Technology Data Exchange (ETDEWEB)

    Page, S.J.; Organiscak, J.A. [NIOSH, Pittsburgh, PA (United States). Pittsburgh Research Lab.

    2002-06-01

    Laboratory crushing experiments were conducted on a range of low to high volatile bituminous coals to investigate the various factors influencing airborne respirable dust generation. Bituminous coal samples from 8 mines (5 U.S. and 3 Polish) were uniformly prepared and processed through a double roll crusher located in a low air velocity wind tunnel. Experimental factors studied included inherent coal seam constituents, specific energy of crushing, product size characteristics, dust cloud electrostatic field, and specific quantity of airborne respirable dust generated. A combination of factors is associated with the generation of airborne respirable dust. One factor involved is the effect of coal rank, described by the inherent moist fuel ratio, on the product size characteristics. However, since coals of high moist fuel ratio (high rank) are generally more extensively cleated, it is suggested that the degree of cleating is directly responsible for the quantity of respirable-sized particles produced in the crushed product material for eastern U.S. coals. This is implied by the relationship of ash content and at least one mineral constituent (pyrite, determined from pyritic sulfur analysis) to the percentage of airborne respirable dust. A clear delineation of coals, based on well-known proximate analysis characteristics, that generate the most respirable dust appears to be possible. It was also shown that the dust-generating characteristics of coals could be reasonably described by both the moist fuel ratio and the Hardgrove Grindability Index (HGI). These results show a clear distinction between eastern and western U.S. coals. However, no consistent distinction for Polish coal was observed.

  20. Numerical study of bituminous coal combustion in a boiler furnace with bottom blowing

    Science.gov (United States)

    Zroychikov, N. A.; Kaverin, A. A.

    2016-11-01

    Results obtained by the numerical study of a solid fuel combustion scheme with bottom blowing using Ekibastuz and Kuznetsk bituminous coals of different fractional makeup are presented. Furnace chambers with bottom blowing provide high-efficiency combustion of coarse-grain coals with low emissions of nitrogen oxides. Studying such a combustion scheme, identification of its technological capabilities, and its further improvement are topical issues. As the initial object of study, we selected P-57-R boiler plant designed for burning of Ekibastuz bituminous coal in a prismatic furnace with dry-ash (solid slag) removal. The proposed modernization of the furnace involves a staged air inflow under the staggered arrangement of directflow burners (angled down) and bottom blowing. The calculation results revealed the specific aerodynamics of the flue gases, the trajectories of solid particles in the furnace chamber, and the peculiarities of the fuel combustion depending on the grinding fineness. It is shown that, for coal grinding on the mill, the overall residue on the screen plate of 90 µm ( R 90 ≤ 27% for Ekibastuz coal and R 90 ≤ 15% for Kuznetsk coal) represents admissible values for fuel grind coarsening in terms of economic efficiency and functional reliability of a boiler. The increase in these values leads to the excess of regulatory heat losses and unburned combustible losses. It has been established that the change in the grade of the burned coal does not significantly affect the flow pattern of the flue gases, and the particles trajectory is essentially determined by the elemental composition of the fuel.

  1. Infrared differential interference contrast microscopy for 3D interconnect overlay metrology.

    Science.gov (United States)

    Ku, Yi-sha; Shyu, Deh-Ming; Lin, Yeou-Sung; Cho, Chia-Hung

    2013-08-12

    One of the main challenges for 3D interconnect metrology of bonded wafers is measuring through opaque silicon wafers using conventional optical microscopy. We demonstrate here the use infrared microscopy, enhanced by implementing the differential interference contrast (DIC) technique, to measure the wafer bonding overlay. A pair of two dimensional symmetric overlay marks were processed at both the front and back sides of thinned wafers to evaluate the bonding overlay. A self-developed analysis algorithm and theoretical fitting model was used to map the overlay error between the bonded wafers and the interconnect structures. The measurement accuracy was found to be better than 1.0 micron.

  2. Lightweight storage and overlay networks for fault tolerance.

    Energy Technology Data Exchange (ETDEWEB)

    Oldfield, Ron A.

    2010-01-01

    The next generation of capability-class, massively parallel processing (MPP) systems is expected to have hundreds of thousands to millions of processors, In such environments, it is critical to have fault-tolerance mechanisms, including checkpoint/restart, that scale with the size of applications and the percentage of the system on which the applications execute. For application-driven, periodic checkpoint operations, the state-of-the-art does not provide a scalable solution. For example, on today's massive-scale systems that execute applications which consume most of the memory of the employed compute nodes, checkpoint operations generate I/O that consumes nearly 80% of the total I/O usage. Motivated by this observation, this project aims to improve I/O performance for application-directed checkpoints through the use of lightweight storage architectures and overlay networks. Lightweight storage provide direct access to underlying storage devices. Overlay networks provide caching and processing capabilities in the compute-node fabric. The combination has potential to signifcantly reduce I/O overhead for large-scale applications. This report describes our combined efforts to model and understand overheads for application-directed checkpoints, as well as implementation and performance analysis of a checkpoint service that uses available compute nodes as a network cache for checkpoint operations.

  3. Replication in Overlay Networks: A Multi-objective Optimization Approach

    Science.gov (United States)

    Al-Haj Hassan, Osama; Ramaswamy, Lakshmish; Miller, John; Rasheed, Khaled; Canfield, E. Rodney

    Recently, overlay network-based collaborative applications such as instant messaging, content sharing, and Internet telephony are becoming increasingly popular. Many of these applications rely upon data-replication to achieve better performance, scalability, and reliability. However, replication entails various costs such as storage for holding replicas and communication overheads for ensuring replica consistency. While simple rule-of-thumb strategies are popular for managing the cost-benefit tradeoffs of replication, they cannot ensure optimal resource utilization. This paper explores a multi-objective optimization approach for replica management, which is unique in the sense that we view the various factors influencing replication decisions such as access latency, storage costs, and data availability as objectives, and not as constraints. This enables us to search for solutions that yield close to optimal values for these parameters. We propose two novel algorithms, namely multi-objective Evolutionary (MOE) algorithm and multi-objective Randomized Greedy (MORG) algorithm for deciding the number of replicas as well as their placement within the overlay. While MOE yields higher quality solutions, MORG is better in terms of computational efficiency. The paper reports a series of experiments that demonstrate the effectiveness of the proposed algorithms.

  4. Algorithms for Constructing Overlay Networks For Live Streaming

    CERN Document Server

    Andreev, Konstantin; Meyerson, Adam; Saks, Jevan; Sitaraman, Ramesh K

    2011-01-01

    We present a polynomial time approximation algorithm for constructing an overlay multicast network for streaming live media events over the Internet. The class of overlay networks constructed by our algorithm include networks used by Akamai Technologies to deliver live media events to a global audience with high fidelity. We construct networks consisting of three stages of nodes. The nodes in the first stage are the entry points that act as sources for the live streams. Each source forwards each of its streams to one or more nodes in the second stage that are called reflectors. A reflector can split an incoming stream into multiple identical outgoing streams, which are then sent on to nodes in the third and final stage that act as sinks and are located in edge networks near end-users. As the packets in a stream travel from one stage to the next, some of them may be lost. A sink combines the packets from multiple instances of the same stream (by reordering packets and discarding duplicates) to form a single in...

  5. 用于网格计算的Overlay Network 设计算法的研究%Research on Overlay Network Topology Design Algorithm Used in Grid

    Institute of Scientific and Technical Information of China (English)

    曹怀虎; 余镇危; 潘耘

    2006-01-01

    针对如何提供丰富的通信交互提出了一种基于Overlay Network 的网格架构,设计Overlay Network,给出了一种动态环境中分布式拉格朗日启发式算法DLagrOTDP,计算的结果显示该算法具有更快的适应性.

  6. Trends in Development of Weld Overlaying During The 21ST Century

    Directory of Open Access Journals (Sweden)

    Nikolov Mitko

    2014-08-01

    Full Text Available The present article discusses the trends in the development of welding and weld overlaying on the threshold of the new millennium and during it. It presents the trends in the production of welding materials for welding and weld overlaying in industrially developed and developing countries. The structure of welding methods is also shown, giving priority to its development until 2020.

  7. Questioning the Benefits That Coloured Overlays Can Have for Reading in Students with and without Dyslexia

    Science.gov (United States)

    Henderson, Lisa M.; Tsogka, Natassa; Snowling, Margaret J.

    2013-01-01

    Visual stress (the experience of visual distortions and discomfort during prolonged reading) is frequently identified and alleviated with coloured overlays or lenses. Previous studies have associated visual stress with dyslexia and as a consequence, coloured overlays are widely distributed to children and adults with reading difficulty. However,…

  8. FLUORESCENCE OVERLAY ANTIGEN MAPPING OF THE EPIDERMAL BASEMENT-MEMBRANE ZONE .1. GEOMETRIC ERRORS

    NARCIS (Netherlands)

    BRUINS, S; DEJONG, MCJM; HEERES, K; WILKINSON, MHF; JONKMAN, MF; VANDERMEER, JB

    1994-01-01

    To identify in tissue sections the relative positions of antigen distributions close to the resolving power of the microscope, we have developed the fluorescence overlay antigen mapping (FOAM) procedure. As this technique makes high demands on the geometric fidelity of the overlay image, it is essen

  9. Viral concentration determination through plaque assays: using traditional and novel overlay systems.

    Science.gov (United States)

    Baer, Alan; Kehn-Hall, Kylene

    2014-11-04

    Plaque assays remain one of the most accurate methods for the direct quantification of infectious virons and antiviral substances through the counting of discrete plaques (infectious units and cellular dead zones) in cell culture. Here we demonstrate how to perform a basic plaque assay, and how differing overlays and techniques can affect plaque formation and production. Typically solid or semisolid overlay substrates, such as agarose or carboxymethyl cellulose, have been used to restrict viral spread, preventing indiscriminate infection through the liquid growth medium. Immobilized overlays restrict cellular infection to the immediately surrounding monolayer, allowing the formation of discrete countable foci and subsequent plaque formation. To overcome the difficulties inherent in using traditional overlays, a novel liquid overlay utilizing microcrystalline cellulose and carboxymethyl cellulose sodium has been increasingly used as a replacement in the standard plaque assay. Liquid overlay plaque assays can be readily performed in either standard 6 or 12 well plate formats as per traditional techniques and require no special equipment. Due to its liquid state and subsequent ease of application and removal, microculture plate formats may alternatively be utilized as a rapid, accurate and high throughput alternative to larger scale viral titrations. Use of a non heated viscous liquid polymer offers the opportunity to streamline work, conserves reagents, incubator space, and increases operational safety when used in traditional or high containment labs as no reagent heating or glassware are required. Liquid overlays may also prove more sensitive than traditional overlays for certain heat labile viruses.

  10. Live 3D image overlay for arterial duct closure with Amplatzer Duct Occluder II additional size.

    Science.gov (United States)

    Goreczny, Sebstian; Morgan, Gareth J; Dryzek, Pawel

    2016-03-01

    Despite several reports describing echocardiography for the guidance of ductal closure, two-dimensional angiography remains the mainstay imaging tool; three-dimensional rotational angiography has the potential to overcome some of the drawbacks of standard angiography, and reconstructed image overlay provides reliable guidance for device placement. We describe arterial duct closure solely from venous approach guided by live three-dimensional image overlay.

  11. A cortical locus for anisotropic overlay suppression of stimuli presented at fixation.

    Science.gov (United States)

    Hansen, Bruce C; Richard, Bruno; Andres, Kristin; Johnson, Aaron P; Thompson, Benjamin; Essock, Edward A

    2015-01-01

    Human contrast sensitivity for narrowband Gabor targets is suppressed when superimposed on narrowband masks of the same spatial frequency and orientation (referred to as overlay suppression), with suppression being broadly tuned to orientation and spatial frequency. Numerous behavioral and neurophysiological experiments have suggested that overlay suppression originates from the initial lateral geniculate nucleus (LGN) inputs to V1, which is consistent with the broad tuning typically reported for overlay suppression. However, recent reports have shown narrowly tuned anisotropic overlay suppression when narrowband targets are masked by broadband noise. Consequently, researchers have argued for an additional form of overlay suppression that involves cortical contrast gain control processes. The current study sought to further explore this notion behaviorally using narrowband and broadband masks, along with a computational neural simulation of the hypothesized underlying gain control processes in cortex. Additionally, we employed transcranial direct current stimulation (tDCS) in order to test whether cortical processes are involved in driving narrowly tuned anisotropic suppression. The behavioral results yielded anisotropic overlay suppression for both broadband and narrowband masks and could be replicated with our computational neural simulation of anisotropic gain control. Further, the anisotropic form of overlay suppression could be directly modulated by tDCS, which would not be expected if the suppression was primarily subcortical in origin. Altogether, the results of the current study provide further evidence in support of an additional overlay suppression process that originates in cortex and show that this form of suppression is also observable with narrowband masks.

  12. Fundamentals of overlay measurement and inspection using scanning electron-microscope

    Science.gov (United States)

    Kato, T.; Okagawa, Y.; Inoue, O.; Arai, K.; Yamaguchi, S.

    2013-04-01

    Scanning electron-microscope (SEM) has been successfully applied to CD measurement as promising tools for qualifying and controlling quality of semiconductor devices in in-line manufacturing process since 1985. Furthermore SEM is proposed to be applied to in-die overlay monitor in the local area which is too small to be measured by optical overlay measurement tools any more, when the overlay control limit is going to be stringent and have un-ignorable dependence on device pattern layout, in-die location, and singular locations in wafer edge, etc. In this paper, we proposed new overlay measurement and inspection system to make an effective use of in-line SEM image, in consideration of trade-off between measurement uncertainty and measurement pattern density in each SEM conditions. In parallel, we make it clear that the best hybrid overlay metrology is in considering each tool's technology portfolio.

  13. Analysis of an Orthotropic Deck Stiffened with a Cement-Based Overlay

    DEFF Research Database (Denmark)

    Walter, Rasmus; Olesen, John Forbes; Stang, Henrik;

    2007-01-01

    Over the past years, with increasing traffic volumes and higher wheel loads, fatigue damage in steel parts of typical orthotropic steel bridge decks has been experienced on heavily trafficked routes. A demand exists to find a durable system to increase the fatigue safety of orthotropic steel bridge...... decks. A solution might be to enhance the stiffness of the traditional orthotropic bridge deck by using a cement-based overlay. In this paper, an orthotropic steel bridge deck stiffened with a cement-based overlay is analyzed. The analysis is based on nonlinear fracture mechanics, and utilizes...... the finite-element method. The stiffness of the steel deck reinforced with an overlay depends highly on the composite action. The composite action is closely related to cracking of the overlay and interfacial cracking between the overlay and underlying steel plate (debonding). As an example, a real size...

  14. Effect of PCC Joint Skew on Reflective Cracking in HMA Overlays

    CERN Document Server

    Ghauch, By Ziad G

    2011-01-01

    Reflective cracking is a relatively premature distress that occurs in HMA materials overlaying cracked and jointed underlying pavements. The high concentration of stresses and strains in the vicinity of the discontinuity of the old pavement causes the cracks to reflect into the newly placed HMA overlay. While it is a common practice to use skewed transverse joints in rigid pavements to improve the latter's performance, the impact of such a practice on the cracking of a potential HMA overlay has not been examined so far. In this context, this study investigates the effect of using skewed transverse joints in rigid pavements on reflective cracking development in the HMA overlay. Advanced three-dimensional Finite Element models including viscoelastic material properties for the HMA overlay, 3D beam modeling of dowel bars, non-uniform tire-pavement contact stresses, friction interfaces, and infinite boundary elements were constructed for both normal and skewed transverse joints using ABAQUS v-6.11. The potential ...

  15. Strain Response of Hot-Mix Asphalt Overlays for Bottom-Up Reflective Cracking

    CERN Document Server

    Ghauch, Ziad G

    2011-01-01

    This paper examines the strain response of typical HMA overlays above jointed PCC slabs prone to bottom-up reflective cracking. The occurrence of reflective cracking under the combined effect of traffic and environmental loading significantly reduces the design life of the HMA overlays and can lead to its premature failure. In this context, viscoelastic material properties combined with cyclic vehicle loadings and pavement temperature distribution were implemented in a series of FE models in order to study the evolution of horizontal tensile and shear strains at the bottom of the HMA overlay. The effect of several design parameters, such as subbase and subgrade moduli, vehicle speed, overlay thickness, and temperature condition, on the horizontal and shear strain response was investigated. Results obtained show that the rate of horizontal and shear strain increase at the bottom of the HMA overlay drop with higher vehicle speed, higher subgrade modulus, and higher subbase modulus. Moreover, the rate of horizon...

  16. Axial compression behavior of concrete masonry wallettes strengthened with cement mortar overlays

    Directory of Open Access Journals (Sweden)

    F. L. De Oliveira

    Full Text Available This paper presents the results of a series of axial compression tests on concrete block wallettes coated with cement mortar overlays. Different types of mortars and combinations with steel welded meshes and fibers were tested. The experimental results were discussed based on different theoretical approaches: analytical and Finite Element Method models. The main conclusions are: a the application of mortar overlays increases the wall strength, but not in a uniform manner; b the strengthening efficiency of wallettes loaded in axial compression is not proportional to the overlay mortar strength because it can be affected by the failure mechanisms of the wall; c steel mesh reinforced overlays in combination with high strength mortar show better efficiency, because the steel mesh mitigates the damage effects in the block wall and in the overlays themselves; d simplified theoretical methods of analysis as described in this paper can give satisfactory predictions of masonry wall behavior up to a certain level.

  17. Ubiquitous map-image access through wireless overlay networks

    Science.gov (United States)

    Cai, Jianfei; Huang, Haijie; Ni, Zefeng; Chen, Chang Wen

    2004-10-01

    With the availability of various wireless link-layer technologies, such as Bluetooth, WLAN and GPRS, in one wireless device, ubiquitous communications can be realized through managing vertical handoff in the environment of wireless overlay networks. In this paper, we propose a vertical handoff management system based on mobile IPv6, which can automatically manage the multiple network interfaces on the mobile device, and make decisions on network interface selection according to the current situation. Moreover, we apply our proposed vertical handoff management with JPEG-2000 codec to the wireless application of map image access. The developed system is able to provide seamless communications, as well as fast retrieve any interested map region with any block size, in different resolutions and different color representations directly from the compressed bitstream.

  18. Complete Imageless solution for overlay front-end manufacturing

    Science.gov (United States)

    Herisson, David; LeCacheux, Virginie; Touchet, Mathieu; Vachellerie, Vincent; Lecarpentier, Laurent; Felten, Franck; Polli, Marco

    2005-09-01

    Imageless option of KLA-Tencor RDM system (Recipe Data Management) is a new method of recipe creation, using only the mask design to define alignment target and measurement parameters. This technique is potentially the easiest tool to improve recipe management of a large amount of products in logic fab. Overlay recipes are created without wafer, by using a synthetic image (copy of gds mask file) for alignment pattern and target design like shape (frame in frame) and size for the measurement. A complete gauge study on critical CMOS 90nm Gate level has been conducted to evaluate reliability and robustness of the imageless recipe. We show that Imageless limits drastically the number of templates used for recipe creation, and improves or maintains measurement capability compare to manual recipe creation (operator dependant). Imageless appears to be a suitable solution for high volume manufacturing, as shown by the results obtained on production lots.

  19. Performance Analysis of Vertical Handover Strategy for Heterogeneous Overlay Network

    Institute of Scientific and Technical Information of China (English)

    BINGHongyan; HEChen; JIANGLingge

    2004-01-01

    Future wireless networks are envisioned to integrate cellular network and hot spots (e.g. ultrawideband network, UWB) in virtue of the individual coverage and capacity complementary characteristics. In this heterogeneous overlay network, seamless Vertical handover (VHO) is one of the important issues because users expect to be provided with continuous service at anytime, anywhere. This paper presents an analytical vertical handover initiation model based on Received signal strength(RSS) criterion and network blocking probability criterion. Meanwhile, the handover performance criteria of interest are: the handover probability and call-dropping probability. The analytical formulas are derived in details and the handover performance is evaluated by computer simulations. The simulation results show that our model can give improved performance compared with vertical HO algorithm only based on RSS criterion and can perform well when UWB hot spot is in heavy network load.

  20. Overlay removable denture for treatment of worn teeth.

    Science.gov (United States)

    Beyth, Nurit; Tamari, Israel; Buller Sharon, Anat

    2014-01-01

    Rehabilitation of partially edentulous patients with excessively worn dentitions can be challenging. Factors including medical history as well as the cost of the treatment and patient wishes for simpler approaches must be considered. This manuscript describes the use of an overlay partial denture to treat patients with excessive wear of the maxillary teeth. We describe a technique to restore severely worn teeth using heat-cured acrylic as part of a partial or full denture. Minimal preparations of the teeth are required, and the restoration provides protection from further wear, and stabilizes the occlusion. This solution was functionally and esthetically suitable to the patients. The technique can be used in medically complex patients where extractions are contraindicated, such as post radiation therapy or bisphosphonate treatment.

  1. Overlay cognitive radio systems with adaptive two-way relaying

    KAUST Repository

    Hyadi, Amal

    2013-12-01

    In this paper, we propose a spectrum sharing mechanism with a two-phase two-way relaying protocol for an overlay cognitive network. The system comprises two primary users (PUs) and two secondary users (SUs). One of the SUs acts as a relay for the PUs and gains spectrum sharing as long as he respects outage probability constraints of the primary system. Moreover, we consider that the relaying node performs an optimal power allocation scheme that minimizes the outage performance of the secondary receiver. Closed form expressions for the outage probability are derived for the cases of Decode-and-Forward (DF), Amplify-and-Forward (AF), and adaptive relaying. Numerical simulations are presented to illustrate and compare the obtained results. © 2013 IEEE.

  2. Assessment of an Impulse GPR Antenna Abilities in Investigation of Transversal Cracks of the Bituminous Pavement

    Science.gov (United States)

    Krysiński, L.; Sudyka, J.

    2012-04-01

    Ground Penetrating Radar (GPR) technique is commonly used for detection of internal singularities of construction structure. The method is particularly efficient in the case of linear horizontal objects when profile scanning is being performed in the direction perpendicular to object elongation and polarization of the electric field is parallel to the elongation. Then the singular object manifests itself in the echogram as a scattering hyperbola. Similar response is generated by an object having shape close to a vertical half plane with horizontal edge, when the edge acts like the scattering linear object. The use of GPR technique for investigation of transversal cracks in the bituminous pavement would seem to be promising, but numerous paradoxes occur just at the beginning tests. Even well visible cracks of more than ten millimeters thickness doesn't generate noticeable GPR response, while thinner ones sometimes can produce strong response but in the deeper interior of the pavement. Thus arise a more general question: what the GPR technique can tell us about the cracks? Trying to study this problem some laboratory tests were performed to estimate efficiency of signal generation by structures simulating idealized cracks' shapes. Next long-term (several years) visual observation and repeated GPR scanning was performed on the three road sections (each one of several hundred meters length) with heavy traffic, where ongoing cracking process occurs. The preliminary measurements were directed to obtain the proper way of scanning. The main aim of the analysis was to find GPR characteristics of cracks that can be noticed on echograms. It was performed by detailed correlation of the visually observed cracks position with echograms using decimeter precision. These efforts provided a list of diagnostic GPR characteristics of cracks and some provisional scale of their intensity. In several cases the cracks were probed by drillings to recognize structures responsible for signal

  3. Experimental and computational study and development of the bituminous coal entrained-flow air-blown gasifier for IGCC

    Science.gov (United States)

    Abaimov, N. A.; Osipov, P. V.; Ryzhkov, A. F.

    2016-10-01

    In the paper the development of the advanced bituminous coal entrained-flow air- blown gasifier for the high power integrated gasification combined cycle is considered. The computational fluid dynamics technique is used as the basic development tool. The experiment on the pressurized entrained-flow gasifier was performed by “NPO CKTI” JSC for the thermochemical processes submodel verification. The kinetic constants for Kuznetsk bituminous coal (flame coal), obtained by thermal gravimetric analysis method, are used in the model. The calculation results obtained by the CFD model are in satisfactory agreements with experimental data. On the basis of the verified model the advanced gasifier structure was suggested which permits to increase the hydrogen content in the synthesis gas and consequently to improve the gas turbine efficiency. In order to meet the specified requirements vapor is added on the second stage of MHI type gasifier and heat necessary for air gasification is compensated by supplemental heating of the blasting air.

  4. Valorization of bituminous coal pulps using column flotation; Valorisation de fines de charbon bitumineux par flottation en colonnes

    Energy Technology Data Exchange (ETDEWEB)

    Gursu, G.; Hicyilmaz, C. [Universite du Moyen-Orient, Ankara (Turkey); Bilgen, S. [Universite de Mersin (Turkey)

    2001-03-01

    Washing tests were performed with 5 x 5 x 200 cm{sup 3} laboratory flotation columns on bituminous coal pulps from Zonguldak (Turkey) containing 47.52% of ash. The final product contains 10% of ash with a 73.52% recovery. A re-washing of this concentrate allows to obtain a final product with 5.88% of ash and a 59.27% recovery. Abstract only. (J.S.)

  5. Potential of water-washing of rape straw on thermal properties and interactions during co-combustion with bituminous coal.

    Science.gov (United States)

    Ma, Qiulin; Han, Lujia; Huang, Guangqun

    2017-03-07

    The aim of this work was to study the thermal properties and interactions during co-combustion of rape straw (RS) before and after water-washing with bituminous coal. A series of experiments was conducted to investigate the properties and interactions during co-combustion of RS with bituminous coal (at 10, 20, 40 and 60% RS). The feasibility and potential of water-washing as an RS pre-treatment was also explored. Reactivity and the amount of heat released followed a quadratic trend, while changes to the degree of interactions between the fuels conformed to a cosine curve. Water-washing increased the ignition and burn-out temperatures and slightly decreased reactivity. Demineralization negatively affected the previously synergistic co-firing relationship, nevertheless, the amount of heat released increased by 10.28% and the average activation energy (146kJ/mol) was lower than that of the unwashed blend (186kJ/mol). Overall, water-washing of RS could prove a useful pre-treatment before co-combustion with bituminous coal.

  6. Catalytic Two-Stage Liquefaction (CTSL) process bench studies with bituminous coal. Final report, [October 1, 1988--December 31, 1992

    Energy Technology Data Exchange (ETDEWEB)

    Comolli, A.G.; Johanson, E.S.; Karolkiewicz, W.F.; Lee, L.K.; Stalzer, R.H.; Smith, T.O.

    1993-03-01

    Reported herein are the details and results of Laboratory and Bench-Scale experiments using bituminous coal concluded at Hydrocarbon Research, Inc., under DOE contract during the period October 1, 1988 to December 31, 1992. The work described is primarily concerned with the application of coal cleaning methods and solids separation methods to the Catalytic Two-Stage Liquefaction (CTSL) Process. Additionally a predispersed catalyst was evaluated in a thermal/catalytic configuration, and an alternative nickel molybdenum catalyst was evaluated for the CTSL process. Three coals were evaluated in this program: Bituminous Illinois No. 6 Burning Star and Sub-bituminous Wyoming Black Thunder and New Mexico McKinley Mine seams. The results from a total of 16 bench-scale runs are reported and analyzed in detail. The tests involving the Illinois coal are reported herein, and the tests involving the Wyoming and New Mexico coals are described in Topical Report No. 1. On the laboratory scale, microautoclave tests evaluating coal, start-up oils, catalysts, thermal treatment, CO{sub 2} addition and sulfur compound effects are reported in Topical Report No. 3. Other microautoclave tests, such as tests on rejuvenated catalyst, coker liquids, and cleaned coals, are described in the Bench Run sections to which they refer. The microautoclave tests conducted for modelling the CTSL process are described in the CTSL Modelling section of Topical Report No. 3 under this contract.

  7. Chemistry of thermally altered high volatile bituminous coals from southern Indiana

    Science.gov (United States)

    Walker, R.; Mastalerz, Maria; Brassell, S.; Elswick, E.; Hower, J.C.; Schimmelmann, A.

    2007-01-01

    The optical properties and chemical characteristics of two thermally altered Pennsylvanian high volatile bituminous coals, the non-coking Danville Coal Member (Ro = 0.55%) and the coking Lower Block Coal Member (Ro = 0.56%) were investigated with the purpose of understanding differences in their coking behavior. Samples of the coals were heated to temperatures of 275????C, 325????C, 375????C and 425????C, with heating times of up to one hour. Vitrinite reflectance (Ro%) rises with temperature in both coals, with the Lower Block coal exhibiting higher reflectance at 375????C and 425????C compared to the Danville coal. Petrographic changes include the concomitant disappearance of liptinites and development of vesicles in vitrinites in both coals, although neither coal developed anisotropic coke texture. At 375????C, the Lower Block coal exhibits a higher aromatic ratio, higher reflectance, higher carbon content, and lower oxygen content, all of which indicate a greater degree of aromatization at this temperature. The Lower Block coal maintains a higher CH2/CH3 ratio than the Danville coal throughout the heating experiment, indicating that the long-chain unbranched aliphatics contained in Lower Block coal liptinites are more resistant to decomposition. As the Lower Block coal contains significant amounts of liptinite (23.6%), the contribution of aliphatics from these liptinites appears to be the primary cause of its large plastic range and high fluidity. ?? 2006 Elsevier B.V. All rights reserved.

  8. Using proximate analysis to characterize airborne dust generation from bituminous coals

    Energy Technology Data Exchange (ETDEWEB)

    Page, S.J.; Organiscak, J.A.

    2005-11-01

    Prolonged exposure to airborne respirable coal dust is responsible for coal workers pneumoconiosis (CWP), commonly called black lung. Health research studies have identified that the prevalence and severity of CWP are directly related to both the amount of dust exposure and the coal rank. The amount of airborne respirable dust (ARD) smaller than 10 micrometers generated from breakage of different coals varies widely. To investigate the cause, researchers for the National Institute for Occupational Safety and Health (NIOSH) have conducted experiments to identify the causes of airborne respirable dust liberation. Laboratory crushing experiments were conducted on a range of low to high volatile bituminous coals from eight mines. The results indicate that the proximate analysis of a coal sample can provide a very good indicator of the potential for a dust problem. For application to the coal mining, processing, and utilization industries, data from 977 US coal seams compiled by the Department of Energy (DoE) has been used to calculate this dust generation potential from an equation based on the NIOSH measured data. A simple procedure for this calculation is provided. 1 fig.

  9. Comparing potentials for gas outburst in a Chinese anthracite and an Australian bituminous coal mine

    Institute of Scientific and Technical Information of China (English)

    Li Guoqing; Saghafi Abouna

    2014-01-01

    Gas outbursts in underground mining occur under conditions of high gas desorption rate and gas content, combined with high stress regime, low coal strength and high Young’s modulus. This combination of gas and stress factors occurs more often in deep mining. Hence, as the depth of mining increases, the poten-tial for outburst increases. This study proposes a conceptual model to evaluate outburst potential in terms of an outburst indicator. The model was used to evaluate the potential for gas outburst in two mines, by comparing numerical simulations of gas flow behavior under typical stress regimes in an Australian gassy mine extracting a medium-volatile bituminous coal, and a Chinese gassy coal mine in Qinshui Basin (Shanxi province) extracting anthracite coal. We coupled the stress simulation program (FLAC3D) with the gas simulation program (SIMED II) to compute the stress and gas pressure and gas content distribution following development of a roadway into the targeted coal seams. The data from gas content and stress distribution were then used to quantify the intensity of energy release in the event of an outburst.

  10. Recycling of polyethylene terephthalate (PET plastic bottle wastes in bituminous asphaltic concrete

    Directory of Open Access Journals (Sweden)

    Adebayo Olatunbosun Sojobi

    2016-12-01

    Full Text Available This research sheds light on the concept of eco-friendly road construction which comprises eco-design, eco-extraction, eco-manufacturing, eco-construction, eco-rehabilitation, eco-maintenance, eco-demolition, and socioeconomic empowerment. It also revealed the challenges being faced in its adoption and the benefits derivable from its application. Furthermore, the effects of recycling PET plastic bottle wastes produced in North Central Nigeria in bituminous asphaltic concrete (BAC used in flexible pavement construction were also evaluated. The mix design consists of 60/70 penetration-grade asphaltic concrete (5%, 68% coarse aggregate, 6% fine aggregate, and 21% filler using the dry process at 170°C. The optimum bitumen content (OBC for conventional BAC was obtained as 4% by weight of total aggregates and filler. Polymer-coated aggregate (PCA-modified BAC seems preferable because it has the potential to utilize more plastic wastes with a higher optimum plastic content (OPC of 16.7% by weight of total aggregates and filler compared to that of 9% by weight of OBC achieved by PMB-BAC. For both PMB- and PCA-modified BAC, an increase in air void, void in mineral aggregate, and Marshall stability were observed. Eco-friendly road construction which recycles PET wastes should be encouraged by government considering its potential environmental and economic benefits.

  11. Burnout behaviour of bituminous coals in air-staged combustion conditions

    Energy Technology Data Exchange (ETDEWEB)

    Kluger, F.; Spliethoff, H.; Hein, K.R.G. [University of Stuttgart, Stuttgart (Germany). Inst. of Process Engineering and Power Plant (IVD)

    2001-07-01

    In order to determine the influence on burnout by the combustion conditions and the coal preparation, three bituminous coals sold on the world market, from three different locations in Poland, South Africa, and Australia, were studied more closely. For this purpose, the coals were ground in two different particle size ranges, which, besides the influence of the combustion conditions, such a temperature, residence time, and stoichiometry, made it possible to also investigate the impact on burnout by the coal preparation. The experiments were carried out in an electrically heated entrained-flow reactor with a thermal input of 8.5 kW. The parameters for the experiments are wall temperature (1000-1350{degree}C), air ratio (0.6-1.15) and two particle sizes (70% {lt} 75 {mu}m, 90% {lt} 75 {mu}m). The results show that in general, for increasing temperatures, the burnout quality will improve. For the Australian Illawara coal, another outcome is increased NOx emissions. Lowering the air ratio in the reduction zone leads to less NOx emission but to increased unburnt matter in ash. For the smaller particle size fraction, the analysis of the different particle sizes shows an improvement of the burnout without a change in NOx emissions. 10 refs., 10 figs., 2 tabs.

  12. The thermal decomposition studies of three Polish bituminous coking coals and their blends

    Energy Technology Data Exchange (ETDEWEB)

    Krzesinska, M.; Szeluga, U.; Czajkowska, S.; Muszynski, J.; Zachariasz, J.; Pusz, S.; Pilawa, B. [Centre of Polymer and Carbon Materials, Polish Academy of Sciences, Marii Curie-Sklodowskiej 34, 41-819 Zabrze (Poland); Kwiecinska, B. [AGH-University of Science and Technology, Aleja Mickiewicza 30, 30-059 Krakow (Poland); Koszorek, A. [Department of Inorganic Chemistry and Technology, Silesian Technical University, Krzywoustego 6, 44-100 Gliwice (Poland)

    2009-01-31

    The objective of this work was to investigate the thermal decomposition of various bituminous coal blends. Three Polish coals of varying rank (82.7, 86.2 and 88.7 wt.% carbon content) and caking ability (weak, moderate and strong) were collected from the Krupinski, Szczyglowice and Zofiowka mines, respectively. These coals were used to prepare binary and ternary blends. Thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA) were used. The weight loss and heat flow during pyrolysis, and storage/loss elastic modulus measured as a function of increasing temperature were related to the caking ability of coals. Parameters determined with the TGA and the DSC methods in the binary and ternary blends were correlated with the proportion of strongly-caking-coal concentration in the blend. The weight loss of coal blends was found to be additive parameter. The DSC thermograms of binary blends were found to be different from those of the ternary blends, which suggests a different course for this blend pyrolysis. (author)

  13. Analysis and modeling of 3D complex modulus tests on hot and warm bituminous mixtures

    Science.gov (United States)

    Pham, Nguyen Hoang; Sauzéat, Cédric; Di Benedetto, Hervé; González-León, Juan A.; Barreto, Gilles; Nicolaï, Aurélia; Jakubowski, Marc

    2015-05-01

    This paper presents the results of laboratory testing of hot and warm bituminous mixtures containing Reclaimed Asphalt Pavement (RAP). Complex modulus measurements, using the tension-compression test on cylindrical specimens, were conducted to determine linear viscoelastic (LVE) behavior. Sinusoidal cyclic loadings, with strain amplitude of approximately 50ṡ10-6, were applied at several temperatures (from -25 to +45 °C) and frequencies (from 0.03 Hz to 10 Hz). In addition to axial stresses and strains, radial strains were also measured. The complex modulus E ∗ and complex Poisson's ratios ν ∗ were then obtained in two perpendicular directions. Measured values in these two directions do not indicate anisotropy on Poisson's ratio. The time-temperature superposition principle (TTSP) was verified with good approximation in one-dimensional (1D) and three-dimensional (3D) conditions for the same values of shift factor. Experimental results were modeled using the 2S2P1D model previously developed at the University of Lyon/ENTPE. In addition, specific analysis showed that eventual damage created during complex modulus test is very small and is equivalent to the effect of an increase of temperature of about 0.25 °C.

  14. Reduction of wafer-edge overlay errors using advanced correction models, optimized for minimal metrology requirements

    Science.gov (United States)

    Kim, Min-Suk; Won, Hwa-Yeon; Jeong, Jong-Mun; Böcker, Paul; Vergaij-Huizer, Lydia; Kupers, Michiel; Jovanović, Milenko; Sochal, Inez; Ryan, Kevin; Sun, Kyu-Tae; Lim, Young-Wan; Byun, Jin-Moo; Kim, Gwang-Gon; Suh, Jung-Joon

    2016-03-01

    In order to optimize yield in DRAM semiconductor manufacturing for 2x nodes and beyond, the (processing induced) overlay fingerprint towards the edge of the wafer needs to be reduced. Traditionally, this is achieved by acquiring denser overlay metrology at the edge of the wafer, to feed field-by-field corrections. Although field-by-field corrections can be effective in reducing localized overlay errors, the requirement for dense metrology to determine the corrections can become a limiting factor due to a significant increase of metrology time and cost. In this study, a more cost-effective solution has been found in extending the regular correction model with an edge-specific component. This new overlay correction model can be driven by an optimized, sparser sampling especially at the wafer edge area, and also allows for a reduction of noise propagation. Lithography correction potential has been maximized, with significantly less metrology needs. Evaluations have been performed, demonstrating the benefit of edge models in terms of on-product overlay performance, as well as cell based overlay performance based on metrology-to-cell matching improvements. Performance can be increased compared to POR modeling and sampling, which can contribute to (overlay based) yield improvement. Based on advanced modeling including edge components, metrology requirements have been optimized, enabling integrated metrology which drives down overall metrology fab footprint and lithography cycle time.

  15. Prosthodontic management of worn dentition in pediatric patient with complete overlay dentures: a case report.

    Science.gov (United States)

    Kumar, Prince; Rastogi, Jyoti; Jain, Chandni; Singh, Harkanwal Preet

    2012-11-01

    Overlay complete dentures are simple, reversible and economical treatment modality for patients with congenital or acquired disorders that severely affect the tooth development. It satisfies both the esthetic and functional demands where the extraction of teeth is not generally indicated. In pediatric patients, the overlay dentures establish a relatively stable occlusion that improves patient's tolerance to the future treatment procedures for worn dentition. This clinical report highlights the imperative need of appropriate treatment strategy and application of maxillary and mandibular overlay dentures in a pediatric patient who suffered from congenitally mutilated and worn dentition.

  16. An algorithm of multi-model spatial overlay based on three-dimensional terrain model TIN and its application

    Institute of Scientific and Technical Information of China (English)

    WANG Shao-an; ZHANG Zi-ping; GONG Jian-ya

    2001-01-01

    3D-GIS spatial overlay analysis is being broadly concerned about in in ternational academe and is a research focus. It is one of the important function s of spatial analysis using GIS technology. An algorithm of multi-model spatial overlay based on three-dimensional terrain model TIN is introduced in this pape r which can be used to solve the TIN-based three-dimensional overlay operation in spatial analysis. The feasibility and validity of this algorithm is identified. This algorithm is used successfully in three-dimensional overlay and region va riation overlay analysis.

  17. An algorithm of multi-model spatial overlay based on three-dimensional terrain model TIN and its application

    Institute of Scientific and Technical Information of China (English)

    王少安; 张子平; 龚健雅

    2001-01-01

    3D-GIS spatial overlay analysis is being broadly concerned about in international academe and is a research focus. It is one of the important functions of spatial analysis using GIS technology. An algorithm of multi-model spatial overlay based on three-dimensional terrain model TIN is introduced in this paper which can be used to solve the TIN-based thrcc-dimensional overlay operation in spatial analysis. The feasibility arid validity of this algorithm is identified. This algorithm is used successfully in three-dimensional overlay and region variation overlay analysis.

  18. Quality metric for accurate overlay control in <20nm nodes

    Science.gov (United States)

    Klein, Dana; Amit, Eran; Cohen, Guy; Amir, Nuriel; Har-Zvi, Michael; Huang, Chin-Chou Kevin; Karur-Shanmugam, Ramkumar; Pierson, Bill; Kato, Cindy; Kurita, Hiroyuki

    2013-04-01

    The semiconductor industry is moving toward 20nm nodes and below. As the Overlay (OVL) budget is getting tighter at these advanced nodes, the importance in the accuracy in each nanometer of OVL error is critical. When process owners select OVL targets and methods for their process, they must do it wisely; otherwise the reported OVL could be inaccurate, resulting in yield loss. The same problem can occur when the target sampling map is chosen incorrectly, consisting of asymmetric targets that will cause biased correctable terms and a corrupted wafer. Total measurement uncertainty (TMU) is the main parameter that process owners use when choosing an OVL target per layer. Going towards the 20nm nodes and below, TMU will not be enough for accurate OVL control. KLA-Tencor has introduced a quality score named `Qmerit' for its imaging based OVL (IBO) targets, which is obtained on the-fly for each OVL measurement point in X & Y. This Qmerit score will enable the process owners to select compatible targets which provide accurate OVL values for their process and thereby improve their yield. Together with K-T Analyzer's ability to detect the symmetric targets across the wafer and within the field, the Archer tools will continue to provide an independent, reliable measurement of OVL error into the next advanced nodes, enabling fabs to manufacture devices that meet their tight OVL error budgets.

  19. A genetic algorithm for flexible molecular overlay and pharmacophore elucidation

    Science.gov (United States)

    Jones, Gareth; Willett, Peter; Glen, Robert C.

    1995-12-01

    A genetic algorithm (GA) has been developed for the superimposition of sets of flexible molecules. Molecules are represented by a chromosome that encodes angles of rotation about flexible bonds and mappings between hydrogen-bond donor proton, acceptor lone pair and ring centre features in pairs of molecules. The molecule with the smallest number of features in the data set is used as a template, onto which the remaining molecules are fitted with the objective of maximising structural equivalences. The fitness function of the GA is a weighted combination of: (i) the number and the similarity of the features that have been overlaid in this way; (ii) the volume integral of the overlay; and (iii) the van der Waals energy of the molecular conformations defined by the torsion angles encoded in the chromosomes. The algorithm has been applied to a number of pharmacophore elucidation problems, i.e., angiotensin II receptor antagonists, Leu-enkephalin and a hybrid morphine molecule, 5-HT1D agonists, benzodiazepine receptor ligands, 5-HT3 antagonists, dopamine D2 antagonists, dopamine reuptake blockers and FKBP12 ligands. The resulting pharmacophores are generated rapidly and are in good agreement with those derived from alternative means.

  20. Ultrasonic Evaluation of Two Dissimilar Metal Weld Overlay Specimens

    Energy Technology Data Exchange (ETDEWEB)

    Crawford, Susan L.; Cinson, Anthony D.; Prowant, Matthew S.; Moran, Traci L.; Anderson, Michael T.

    2012-06-30

    Two dissimilar metal weld (DMW) pipe-to-nozzle specimens were implanted with thermal fatigue cracks in the 13% to 90% through-wall depth range. The specimens were ultrasonically evaluated with phased-array probes having center frequencies of 0.8, 1.0, 1.5, and 2.0 megahertz (MHz). An Alloy 82/182 weld overlay (WOL) was applied and the specimens were ultrasonically re-evaluated for flaw detection and characterization. The Post-WOL flaw depths were approximately 10% to 56% through-wall. This study has shown the effectiveness of ultrasonic examinations of Alloy 82/182 overlaid DMW specimens. Phased-array probes with center frequency in the 0.8- to 1.0-MHz range provide a strong coherent signal but the greater ultrasonic wavelength and larger beam spot size prevent the reliable detection of small flaws. These small flaws had nominal through-wall depths of less than 15% and length in the 50-60 mm (2-2.4 in.) range. Flaws in the 19% and greater through-wall depth range were readily detected with all four probes. At the higher frequencies, the reflected signals are less coherent but still provide adequate signal for flaw detection and characterization. A single inspection at 2.0 MHz could provide adequate detection and sizing information but a supplemental inspection at 1.0 or 1.5 MHz is recommended.

  1. Variations in pore characteristics in high volatile bituminous coals: Implications for coal bed gas content

    Science.gov (United States)

    Mastalerz, Maria; Drobniak, A.; Strapoc, D.; Solano-Acosta, W.; Rupp, J.

    2008-01-01

    The Seelyville Coal Member of the Linton Formation (Pennsylvanian) in Indiana was studied to: 1) understand variations in pore characteristics within a coal seam at a single location and compare these variations with changes occurring between the same coal at different locations, 2) elaborate on the influence of mineral-matter and maceral composition on mesopore and micropore characteristics, and 3) discuss implications of these variations for coal bed gas content. The coal is high volatile bituminous rank with R0 ranging from 0.57% to 0.60%. BET specific surface areas (determined by nitrogen adsorption) of the coals samples studied range from 1.8 to 22.9??m2/g, BJH adsorption mesopore volumes from 0.0041 to 0.0339??cm3/g, and micropore volumes (determined by carbon dioxide adsorption) from 0.0315 to 0.0540??cm3/g. The coals that had the largest specific surface areas and largest mesopore volumes occur at the shallowest depths, whereas the smallest values for these two parameters occur in the deepest coals. Micropore volumes, in contrast, are not depth-dependent. In the coal samples examined for this study, mineral-matter content influenced both specific surface area as well as mesopore and micropore volumes. It is especially clear in the case of micropores, where an increase in mineral-matter content parallels the decrease of micropore volume of the coal. No obvious relationships were observed between the total vitrinite content and pore characteristics but, after splitting vitrinite into individual macerals, we see that collotelinite influences both meso- and micropore volume positively, whereas collodetrinite contributes to the reduction of mesopore and micropore volumes. There are large variations in gas content within a single coal at a single location. Because of this variability, the entire thickness of the coal must be desorbed in order to determine gas content reliably and to accurately calculate the level of gas saturation. ?? 2008 Elsevier B.V. All

  2. An evaluation of a two-stage spiral processing ultrafine bituminous coal

    Energy Technology Data Exchange (ETDEWEB)

    Matthew D. Benusa; Mark S. Klima [Penn State University, University Park, PA (United States). Energy and Mineral Engineering

    2008-10-15

    Testing was conducted to evaluate the performance of a multistage Multotec SX7 spiral concentrator treating ultrafine bituminous coal. This spiral mimics a two-stage separation in that the refuse is removed after four turns, and the clean coal and middlings are repulped (without water addition) and then separated in the final three turns. Feed samples were collected from the spiral circuit of a coal cleaning plant located in southwestern Pennsylvania. The samples consisted of undeslimed cyclone feed (nominal -0.15 mm) and deslimed spiral feed (nominal 0.15 x 0.053 mm). Testing was carried out to investigate the effects of slurry flow rate and solids concentration on spiral performance. Detailed size and ash analyses were performed on the spiral feed and product samples. For selected tests, float-sink and sulfur analyses were performed. In nearly all cases, ash reduction occurred down to approximately 0.025 mm, with some sulfur reduction occurring even in the -0.025 mm interval. The separation of the +0.025 mm material was not significantly affected by the presence of the -0.025 mm material when treating the undeslimed feed. The -0.025 mm material split in approximately the same ratio as the slurry, and the majority of the water traveled to the clean coal stream. This split ultimately increased the overall clean coal ash value. A statistical analysis determined that both flow rate and solids concentration affected the clean coal ash value and yield, though the flow rate had a greater effect on the separation. 23 refs.

  3. Mercury speciation and distribution in a 660-megawatt utility boiler in Taiwan firing bituminous coals.

    Science.gov (United States)

    Hsi, Hsing-Cheng; Lee, Hsiu-Hsia; Hwang, Jyh-Feng; Chen, Wang

    2010-05-01

    Mercury speciation and distribution in a 660-MW tangential-fired utility boiler in Taiwan burning Australian and Chinese bituminous coal blends was investigated. Flue gases were simultaneously sampled at the selective catalytic reduction (SCR) inlet, the SCR outlet, the electrostatic precipitator (ESP) outlet, and the stack. Samplings of coal, lime, bottom ash/slag, fly ash, and gypsum slurry were also conducted. Results indicated that flue gases at the inlet to SCR contained a great potion of particle-bound mercury (Hg(p)), 59-92% of the total mercury. Removal of mercury was not observed for the SCR system. However, repartitioning of mercury species across the SCR occurred that significantly increased the portion of elemental mercury (Hg0) to up to 29% and oxidized mercury (Hg2+) to up to 33% in the SCR outlet gas. Overreporting of Hg(p) at the inlet of SCR may cause the observed repartitioning; the high ammonia/nitric oxide circumstance in the SCR unit was also speculated to cause the mercury desorption from ash particles and subsequent reentrance into the gas phase. ESP can remove up to 99% of Hg(p), and wet flue gas desulfurization (FGD) can remove up to 84% of Hg2+. Mercury mass balances were calculated to range between 81 and 127.4%, with an average of 95.7% wherein 56-82% was in ESP fly ash, 8.7-18.6% was retained in the FGD gypsum, and 6.2-26.1% was emitted from the stack. Data presented here suggest that mercury removal can be largely enhanced by increasing the conversion of Hg0 into Hg(p) and Hg2+.

  4. Study on the submicron and micron morphology and the properties of poor bituminous coal burnout

    Energy Technology Data Exchange (ETDEWEB)

    Pei-Fang Fu; Huai-Chun Zhou; Qing-Yan Fang; Hai Yao; Jianrong Qiu; Minghou Xu [Huazhong University of Science and Technology, Wuhan (China). State Key Laboratory of Coal Combustion

    2007-05-15

    Carbon burnout and its reaction mechanism have been widely focused on in the past decades. The properties of burnout, submicron and micron morphology and the reaction mechanism of poor bituminous coal/char (PBC) in a W-shaped power plant boiler was studied and was compared with those in DTF and in TGA, which showed that the degree of PBC burnout in TGA at 1450{sup o}C was greater than or approximately equal to that in a W-shaped boiler, and that the complexity of the reactions among residual char, oxygen and SiO{sub 2} did not seem to result in mass loss in TGA, although the weight percentage of the residual char in ash decreased from 33% ad (air dry basis) at 900{sup o}C to 9% and at 1450{sup o}C. According to the distribution of pores and the properties of the char burnout, the char can be simply categorized into three classes: char burnout easy, char burnout difficult and char burnout very difficult. The differences of the reaction mechanism must be considered while predicting the burning rate and degree of char burnout in a full-scale boiler by making use of experimental results from TGA and DTF. A different char particle contains markedly different amount of carbons, but for a special char particle, the ratio of carbon to ash is generally constant, and an ash shell does not exist on the char surface. The fusion mineral matter composing of C-O-Si-Al is amorphous, not in the form of Al{sub 2}O{sub 3} and SiO{sub 2} above 1450{sup o}C.

  5. 64nm pitch metal1 double patterning metrology: CD and OVL control by SEMCD, image based overlay and diffraction based overlay

    Science.gov (United States)

    Ducoté, Julien; Dettoni, Florent; Bouyssou, Régis; Le-Gratiet, Bertrand; Carau, Damien; Dezauzier, Christophe

    2015-03-01

    Patterning process control of advanced nodes has required major changes over the last few years. Process control needs of critical patterning levels since 28nm technology node is extremely aggressive showing that metrology accuracy/sensitivity must be finely tuned. The introduction of pitch splitting (Litho-Etch-Litho-Etch) at 14FDSOInm node requires the development of specific metrologies to adopt advanced process control (for CD, overlay and focus corrections). The pitch splitting process leads to final line CD uniformities that are a combination of the CD uniformities of the two exposures, while the space CD uniformities are depending on both CD and OVL variability. In this paper, investigations of CD and OVL process control of 64nm minimum pitch at Metal1 level of 14FDSOI technology, within the double patterning process flow (Litho, hard mask etch, line etch) are presented. Various measurements with SEMCD tools (Hitachi), and overlay tools (KT for Image Based Overlay - IBO, and ASML for Diffraction Based Overlay - DBO) are compared. Metrology targets are embedded within a block instanced several times within the field to perform intra-field process variations characterizations. Specific SEMCD targets were designed for independent measurement of both line CD (A and B) and space CD (A to B and B to A) for each exposure within a single measurement during the DP flow. Based on those measurements correlation between overlay determined with SEMCD and with standard overlay tools can be evaluated. Such correlation at different steps through the DP flow is investigated regarding the metrology type. Process correction models are evaluated with respect to the measurement type and the intra-field sampling.

  6. Sorbent Injection for Small ESP Mercury Control in Low Sulfur Eastern Bituminous Coal Flue Gas

    Energy Technology Data Exchange (ETDEWEB)

    Carl Richardson; Katherine Dombrowski; Douglas Orr

    2006-12-31

    This project Final Report is submitted to the U.S. Department of Energy (DOE) as part of Cooperative Agreement DE-FC26-03NT41987, 'Sorbent Injection for Small ESP Mercury Control in Low Sulfur Eastern Bituminous Coal Flue Gas.' Sorbent injection technology is targeted as the primary mercury control process on plants burning low/medium sulfur bituminous coals equipped with ESP and ESP/FGD systems. About 70% of the ESPs used in the utility industry have SCAs less than 300 ft2/1000 acfm. Prior to this test program, previous sorbent injection tests had focused on large-SCA ESPs. This DOE-NETL program was designed to generate data to evaluate the performance and economic feasibility of sorbent injection for mercury control at power plants that fire bituminous coal and are configured with small-sized electrostatic precipitators and/or an ESP-flue gas desulfurization (FGD) configuration. EPRI and Southern Company were co-funders for the test program. Southern Company and Reliant Energy provided host sites for testing and technical input to the project. URS Group was the prime contractor to NETL. ADA-ES and Apogee Scientific Inc. were sub-contractors to URS and was responsible for all aspects of the sorbent injection systems design, installation and operation at the different host sites. Full-scale sorbent injection for mercury control was evaluated at three sites: Georgia Power's Plant Yates Units 1 and 2 [Georgia Power is a subsidiary of the Southern Company] and Reliant Energy's Shawville Unit 3. Georgia Power's Plant Yates Unit 1 has an existing small-SCA cold-side ESP followed by a Chiyoda CT-121 wet scrubber. Yates Unit 2 is also equipped with a small-SCA ESP and a dual flue gas conditioning system. Unit 2 has no SO2 control system. Shawville Unit 3 is equipped with two small-SCA cold-side ESPs operated in series. All ESP systems tested in this program had SCAs less than 250 ft2/1000 acfm. Short-term parametric tests were conducted on Yates

  7. The Effect of Colored Overlays on Reading Fluency in Individuals with Dyslexia.

    Science.gov (United States)

    Denton, Tiffany Freeze; Meindl, James N

    2016-09-01

    Colored overlays, one type of tinted filter, are plastic reading sheets tinted with color and placed over text to eliminate or alleviate a wide range of reading difficulties such as low reading rate, accuracy, and comprehension. The effects of colored overlays on reading problems associated with dyslexia were investigated in this study via a multielement design. Reading fluency was assessed when participants read with and without colored overlays. Undifferentiated responding, or decreased accuracy, resulted across three participants, suggesting that colored overlays were ineffective and potentially detrimental to participants' reading abilities. As a result, empirically validated reading techniques were implemented across individuals. These findings are discussed and recommendations are made in regards to the use of research-based reading interventions.

  8. An optimal algorithm based on extended kalman filter and the data fusion for infrared touch overlay

    Science.gov (United States)

    Zhou, AiGuo; Cheng, ShuYi; Pan, Qiang Biao; Sun, Dong Yu

    2016-01-01

    Current infrared touch overlay has problems on the touch point recognition which bring some burrs on the touch trajectory. This paper uses the target tracking algorithm to improve the recognition and smoothness of infrared touch overlay. In order to deal with the nonlinear state estimate problem for touch point tracking, we use the extended Kalman filter in the target tracking algorithm. And we also use the data fusion algorithm to match the estimate value with the original target trajectory. The experimental results of the infrared touch overlay demonstrate that the proposed target tracking approach can improve the touch point recognition of the infrared touch overlay and achieve much smoother tracking trajectory than the existing tracking approach.

  9. How to minimize CD variation and overlay degradation induced by film stress

    Science.gov (United States)

    Jung, Woo-Yung; Lim, Yong-Hyun; Park, Shin-Ae; Ahn, Sang-Joon; Lee, Ji-Hyun; Yoo, Jung-A.; Pyi, Seung-Ho; Kim, Jin-Woong

    2012-03-01

    It is getting harder to minimize feature size to satisfy bit growth requirement. 3D NAND flash memory has been developed to meet bit growth requirement without shrinking feature size. To increase the number of memory cells per unit area without shrinking feature size, we should increase the number of stacked film layers which finally become memory cells. Wafer warpage is induced by the stress between film and wafer. Both of film stress and wafer warpage increase in proportion to stacked film layers, and the increase of wafer warpage makes CD uniformity worse. Overlay degradation has no relation with wafer warpage, but has indirect relation with film stress. Wafer deformation in film deposition chamber is the source of overlay degradation. In this paper, we study the reasons why CD uniformity and overlay accuracy are affected by film stress, and suggest the methods which keep CD uniformity and overlay accuracy safe without additional processes.

  10. CHC: A Robust P2P Overlay Network with Simple Routing and Small-World Features

    Directory of Open Access Journals (Sweden)

    Wenjun Xiao

    2011-08-01

    Full Text Available Almost all recent researches on P2P systems focus on howto build a highly usable P2P overlay network. Researchersinclude small routing table, short query path and goodrobustness into their design objectives of overlay topology. Inthis paper, we present a general group theory method anddefine a new Cayley graph. Based on this Cayley graph, wepropose a novel P2P overlay network called CHC, which hassimple routing (searching scheme and many other excellentproperties such as short query path, high clustering and goodrobustness because of its symmetry. The performance isevaluated by simulation to show that CHC possesses shorterquery path length and higher clustering and better robustnessthan several popular P2P overlay networks such as Chord andUlysses.

  11. Computing a single cell in the overlay of two simple polygons

    NARCIS (Netherlands)

    Berg, M. de; Devillers, O.; Dobrindt, K.T.G.; Schwarzkopf, O.

    2001-01-01

    This note combines the lazy randomized incremental construction scheme with the technique of \\connectivity acceleration" to obtain an O ( n (log ? n ) 2 ) time randomized algorithm to compute a single face in the overlay oftwo simple polygons in the plane.

  12. 3D Finite Element Analysis of HMA Overlay Mix Design to Control Reflective Cracking

    CERN Document Server

    Ghauch, Ziad G

    2011-01-01

    One of the most common rehabilitation techniques of deteriorated pavements is the placement of an HMA overlay on top of the existing Asphalt Concrete (AC) or Portland Cement Concrete (PCC) pavement. However, shortly after pavement resurfacing, HMA overlays exhibit a cracking pattern similar to that of the underlying pavement. This phenomenon is known as reflective cracking. This study examines the effectiveness of several HMA overlay mix design strategies for the purpose of controlling the development of reflective cracking. A parametric study was conducted using a 3D Finite Element (FE) model of a rigid pavement section including a Linear Viscoelastic (LVE) model for Hot Mix Asphalt (HMA) materials and non-uniform tire-pavement contact stresses. Results obtained show that for the intermediate and surface courses, using a Dense Graded (DG) or Polymer Modified (PM) asphalt mixture instead of a Standard Binder (SB) mixture results in reduced tensile stresses at the bottom of the HMA overlay but higher levels of...

  13. OVERLAY NETWORKS APPLICATION MODEL FOR MILITARY TRAFFIC%Overlay Networks在军事通信中的应用模型

    Institute of Scientific and Technical Information of China (English)

    孙晓; 王晖

    2008-01-01

    首先简单介绍了Overlay Networks,然后分析了当前军事通信的弊端和未来发展趋势,提出采用Overlay Networks的思想,提升军事通信网络的性能,为未来信息化战争提供网络基础架构.最后分析了该应用模型的优点和亟待解决的几个问题.

  14. Bullet: high bandwidth data dissemination using an overlay mesh

    OpenAIRE

    Kostic, D.; Rodriguez, A.; J. Albrecht; Vahdat, A.

    2003-01-01

    In recent years, overlay networks have become an effective alternative to IP multicast for efficient point to multipoint communication across the Internet. Typically, nodes self-organize with the goal of forming an efficient overlay tree, one that meets performance targets without placing undue burden on the underlying network. In this paper, we target high-bandwidth data distribution from a single source to a large number of receivers. Applications include large-file transfers and real-time ...

  15. Application of overlay modeling and control with Zernike polynomials in an HVM environment

    Science.gov (United States)

    Ju, JaeWuk; Kim, MinGyu; Lee, JuHan; Nabeth, Jeremy; Jeon, Sanghuck; Heo, Hoyoung; Robinson, John C.; Pierson, Bill

    2016-03-01

    Shrinking technology nodes and smaller process margins require improved photolithography overlay control. Generally, overlay measurement results are modeled with Cartesian polynomial functions for both intra-field and inter-field models and the model coefficients are sent to an advanced process control (APC) system operating in an XY Cartesian basis. Dampened overlay corrections, typically via exponentially or linearly weighted moving average in time, are then retrieved from the APC system to apply on the scanner in XY Cartesian form for subsequent lot exposure. The goal of the above method is to process lots with corrections that target the least possible overlay misregistration in steady state as well as in change point situations. In this study, we model overlay errors on product using Zernike polynomials with same fitting capability as the process of reference (POR) to represent the wafer-level terms, and use the standard Cartesian polynomials to represent the field-level terms. APC calculations for wafer-level correction are performed in Zernike basis while field-level calculations use standard XY Cartesian basis. Finally, weighted wafer-level correction terms are converted to XY Cartesian space in order to be applied on the scanner, along with field-level corrections, for future wafer exposures. Since Zernike polynomials have the property of being orthogonal in the unit disk we are able to reduce the amount of collinearity between terms and improve overlay stability. Our real time Zernike modeling and feedback evaluation was performed on a 20-lot dataset in a high volume manufacturing (HVM) environment. The measured on-product results were compared to POR and showed a 7% reduction in overlay variation including a 22% terms variation. This led to an on-product raw overlay Mean + 3Sigma X&Y improvement of 5% and resulted in 0.1% yield improvement.

  16. VMCast: A VM-Assisted Stability Enhancing Solution for Tree-Based Overlay Multicast.

    Directory of Open Access Journals (Sweden)

    Weidong Gu

    Full Text Available Tree-based overlay multicast is an effective group communication method for media streaming applications. However, a group member's departure causes all of its descendants to be disconnected from the multicast tree for some time, which results in poor performance. The above problem is difficult to be addressed because overlay multicast tree is intrinsically instable. In this paper, we proposed a novel stability enhancing solution, VMCast, for tree-based overlay multicast. This solution uses two types of on-demand cloud virtual machines (VMs, i.e., multicast VMs (MVMs and compensation VMs (CVMs. MVMs are used to disseminate the multicast data, whereas CVMs are used to offer streaming compensation. The used VMs in the same cloud datacenter constitute a VM cluster. Each VM cluster is responsible for a service domain (VMSD, and each group member belongs to a specific VMSD. The data source delivers the multicast data to MVMs through a reliable path, and MVMs further disseminate the data to group members along domain overlay multicast trees. The above approach structurally improves the stability of the overlay multicast tree. We further utilized CVM-based streaming compensation to enhance the stability of the data distribution in the VMSDs. VMCast can be used as an extension to existing tree-based overlay multicast solutions, to provide better services for media streaming applications. We applied VMCast to two application instances (i.e., HMTP and HCcast. The results show that it can obviously enhance the stability of the data distribution.

  17. VMCast: A VM-Assisted Stability Enhancing Solution for Tree-Based Overlay Multicast.

    Science.gov (United States)

    Gu, Weidong; Zhang, Xinchang; Gong, Bin; Zhang, Wei; Wang, Lu

    2015-01-01

    Tree-based overlay multicast is an effective group communication method for media streaming applications. However, a group member's departure causes all of its descendants to be disconnected from the multicast tree for some time, which results in poor performance. The above problem is difficult to be addressed because overlay multicast tree is intrinsically instable. In this paper, we proposed a novel stability enhancing solution, VMCast, for tree-based overlay multicast. This solution uses two types of on-demand cloud virtual machines (VMs), i.e., multicast VMs (MVMs) and compensation VMs (CVMs). MVMs are used to disseminate the multicast data, whereas CVMs are used to offer streaming compensation. The used VMs in the same cloud datacenter constitute a VM cluster. Each VM cluster is responsible for a service domain (VMSD), and each group member belongs to a specific VMSD. The data source delivers the multicast data to MVMs through a reliable path, and MVMs further disseminate the data to group members along domain overlay multicast trees. The above approach structurally improves the stability of the overlay multicast tree. We further utilized CVM-based streaming compensation to enhance the stability of the data distribution in the VMSDs. VMCast can be used as an extension to existing tree-based overlay multicast solutions, to provide better services for media streaming applications. We applied VMCast to two application instances (i.e., HMTP and HCcast). The results show that it can obviously enhance the stability of the data distribution.

  18. Application Oriented Flow Routing Algorithm for VoIP Overlay Networks

    Science.gov (United States)

    Wipusitwarakun, Komwut; Chimmanee, Sanon

    Overlay networks which are dynamically created over underlying IP networks are becoming widely used for delivering multimedia contents since they can provide several additional user-definable services. Multiple overlay paths between a source-destination overlay node pair are designed to improve service robustness against failures and bandwidth fluctuation of the underlying networks. Multimedia traffic can be distributed over those multiple paths in order to maximize paths' utilization and to increase application throughputs. Most of flow-based routing algorithms consider only common metrics such as paths' bandwidth or delay, which may be effective for data applications but not for real-time applications such as Voice over IP (VoIP), in which different levels of such performance metrics may give the same level of the performance experienced by end users. This paper focuses on such VoIP overlay networks and proposes a novel alternative path based flow routing algorithm using an application-specific traffic metric, i.e. “VoIP Path Capacity (VPCap), ” to calculate the maximum number of QoS satisfied VoIP flows which may be distributed over each available overlay path at a moment. The simulation results proved that more QoS-satisfied VoIP sessions can be established over the same multiple overlay paths, comparing to traditional approaches.

  19. Assessment and prediction of drying shrinkage cracking in bonded mortar overlays

    Energy Technology Data Exchange (ETDEWEB)

    Beushausen, Hans, E-mail: hans.beushausen@uct.ac.za; Chilwesa, Masuzyo

    2013-11-15

    Restrained drying shrinkage cracking was investigated on composite beams consisting of substrate concrete and bonded mortar overlays, and compared to the performance of the same mortars when subjected to the ring test. Stress development and cracking in the composite specimens were analytically modeled and predicted based on the measurement of relevant time-dependent material properties such as drying shrinkage, elastic modulus, tensile relaxation and tensile strength. Overlay cracking in the composite beams could be very well predicted with the analytical model. The ring test provided a useful qualitative comparison of the cracking performance of the mortars. The duration of curing was found to only have a minor influence on crack development. This was ascribed to the fact that prolonged curing has a beneficial effect on tensile strength at the onset of stress development, but is in the same time not beneficial to the values of tensile relaxation and elastic modulus. -- Highlights: •Parameter study on material characteristics influencing overlay cracking. •Analytical model gives good quantitative indication of overlay cracking. •Ring test presents good qualitative indication of overlay cracking. •Curing duration has little effect on overlay cracking.

  20. DEVELOPMENT OF TEST PROTOCOLS FOR THE ANALYSIS OF MAGNETO-RHEOLOGICAL PROPERTIES OF FIELD-RESPONSIVE BITUMINOUS BINDERS

    Directory of Open Access Journals (Sweden)

    Ezio Santagata

    2014-01-01

    Full Text Available Magneto-rheological fluids are materials that exhibit a significant change in their rheological properties in the presence of a magnetic field. Because of such a field-dependent behavior, they can act as smart materials in applications in which changeable performances are desired. In road pavement engineering, the use of bitumen-based magneto-rheological fluids may open innovative scenarios related to the construction of smart pavement sections and to the investigation of damage mechanisms in binders and mixtures. The research work presented in this study explored magneto-rheological properties of several field-responsive bituminous binders obtained from two different base bitumens combined with multi-wall carbon nanotubes and powder iron. The experimental program included oscillatory shear loading tests at different temperatures, performed in the strain controlled mode by means of a dynamic shear rheometer equipped with a magneto-rheological device. The investigation was carried out with the specific goal of identifying critical issues which should be taken into account in materials preparation, testing procedures and data analysis. Undesired overheating of specimens during testing was identified and taken into account for a correct interpretation of experimental data. Thus, while the field-sensitivity of carbon nanotubes was found to be negligible as a result of the magnetic shielding action of bitumen, it was shown that powder iron can significantly affect the magneto-rheological properties of bituminous binders when employed in sufficiently high amounts. Moreover, obtained results indicated that selection of base bitumen is a key factor in designing bituminous-based smart materials. Practical implications which derive from the study are mainly relative to the fine-tuning of laboratory characterization procedures which should necessarily overcome current limitations in temperature regulation and magnetic field generation. Experimental data

  1. Regional differences in the variations of the degree of gas outburst hazard for Mecsek sub-bituminous coal seams

    Energy Technology Data Exchange (ETDEWEB)

    Nemedi Varga, Z.

    1987-01-01

    In the collieries of the Mecsek Mountains (South Hungary) in which the sub-bituminous coal is exploited, coal and gas outbursts as well as gas outbursts have been recorded in the Pecs-area since 1984, in the Szaszvar area since 1902, and nowadays in the Komlo-area since 1964. Concerning the degree of gas outbursts hazard, the differences between the Pecs and Komlo areas cannot be explained by the differences in facies, by structural differences and by the frequency of occurrence of igneous rocks. The conditions of coalification seem to be responsible for these differences. In this respect the significance of the so-called second phase coalification is emphasized.

  2. Non-catalytic co-gasification of sub-bituminous coal and biomass

    Science.gov (United States)

    Nyendu, Guevara Che

    Fluidization characteristics and co-gasification of pulverized sub-bituminous coal, hybrid poplar wood, corn stover, switchgrass, and their mixtures were investigated. Co-gasification studies were performed over temperature range from 700°C to 900°C in different media (N2, CO2, steam) using a bubbling fluidized bed reactor. In fluidization experiments, pressure drop (Delta P) observed for coal-biomass mixtures was higher than those of single coal and biomass bed materials in the complete fluidization regime. There was no systematic trend observed for minimum fluidization velocity ( Umf) with increasing biomass content. However, porosity at minimum fluidization (εmf) increased with increasing biomass content. Channeling effects were observed in biomass bed materials and coal bed with 40 wt.% and 50 wt.% biomass content at low gas flowrates. The effect of coal pressure overshoot reduced with increasing biomass content. Co-gasification of coal and corn stover mixtures showed minor interactions. Synergetic effects were observed with 10 wt.% corn stover. Coal mixed with corn stover formed agglomerates during co-gasification experiments and the effect was severe with increase in corn stover content and at 900°C. Syngas (H2 + CO) concentrations obtained using CO2 as co-gasification medium were higher (~78 vol.% at 700°C, ~87 vol.% at 800°C, ~93 vol.% at 900°C) than those obtained with N2 medium (~60 vol.% at 700°C, ~65 vol.% at 800°C, ~75 vol.% at 900°C). Experiments involving co-gasification of coal with poplar showed no synergetic effects. Experimental yields were identical to predicted yields. However, synergetic effects were observed on H2 production when steam was used as the co-gasification medium. Additionally, the presence of steam increased H2/CO ratio up to 2.5 with 10 wt.% hybrid poplar content. Overall, char and tar yields decreased with increasing temperature and increasing biomass content, which led to increase in product gas.

  3. Organic geochemistry of Upper Carboniferous bituminous coals and clastic sediments from the Lublin Coal Basin

    Science.gov (United States)

    Gola, Marek R.; Karger, Michał; Gazda, Lucjan; Grafka, Oliwia

    2013-09-01

    Bituminous coals and clastic rocks from the Lublin Formation (Pennsylvanian, Westphalian B) were subjected to detailed biomarker and Rock-Eval analyses. The investigation of aliphatic and aromatic fractions and Rock-Eval Tmax suggests that the Carboniferous deposits attained relatively low levels of thermal maturity, at the end of the microbial processes/initial phase of the oil window. Somewhat higher values of maturity in the clastic sediments were caused by postdiagenetic biodegradation of organic matter. The dominance of the odd carbon-numbered n-alkanes in the range n-C25 to n-C31 , high concentrations of moretanes and a predominance of C 28 and C29 steranes are indicative of a terrigenous origin of the organic matter in the study material. This is supported by the presence of eudesmane, bisabolane, dihydro-ar-curcumene and cadalene, found mainly in the coal samples. In addition, tri- and tetracyclic diterpanes, e. g. 16β(H)-kaurane, 16β(H)-phyllocladane, 16α(H)-kaurane and norisopimarane, were identified, suggesting an admixture of conifer ancestors among the deposited higher plants. Parameters Pr/n-C17 and Rdit in the coal samples show deposition of organic matter from peat swamp environments, with the water levels varying from high (water-logged swamp) to very low (ephemeral swamp). Clastic deposits were accumulated in a flood plain environment with local small ponds/lakes. In pond/lake sediments, apart from the dominant terrigenous organic matter, research also revealed a certain quantity of algal matter, indicated, i.a., by the presence of tricyclic triterpanes C28 and C29 and elevated concentrations of steranes. The Paq parameter can prove to be a useful tool in the identification of organic matter, but the processes of organic matter biodegradation observed in clastic rocks most likely influence the value of the parameter, at the same time lowering the interpretation potential of these compounds. The value of Pr/Ph varies from 0.93 to 5.24 and from 3

  4. A system to optimize mix-and-match overlay in lithography

    Science.gov (United States)

    Wakamoto, Shinji; Ishii, Yuuki; Yasukawa, Koji; Maejima, Shinroku; Kato, Atsuhiko; Robinson, John C.; Choi, Dong-Sub

    2008-03-01

    Critical processing factors in the lithography process include overlaying the pattern properly to previous layers and properly exposing the pattern to achieve the desired line width. Proper overlay can only be attained in the lithography process while the desired line width accuracy is achieved by both lithography and etch processes. Since CD is substantially influenced by etch processing, therefore, it is possible to say that overlay is one of the most important processing elements in the lithography process. To achieve the desired overlay accuracy, it is desirable to expose critical layers with the same exposure tool that exposed the previous or target layer. This need to dedicate a particular exposure tool, however, complicates the lot dispatching schedule and, even worse, decreases exposure tool utilization. In order to allow any exposure tool available to print the arriving lot, M&M (Mix and Match) overlay control becomes necessary. By reducing overlay errors in M&M control, lot dispatching scheduling will become more flexible and exposure tool utilization will improve. Since each exposure tool has a unique registration signature, high order errors appear when overlaying multiple layers exposed with different tools. Even with the same exposure tool, if a different illumination is used, a similar error will be seen. A correction scheme to make the signature differences has to be implemented, however manually characterizing each tool's signature per illumination condition is extremely tedious, and is subject human errors. The challenge is to design a system to perform the corrections automatically. In the previous paper(1), we have outlined concepts of the system scheme. The system has subsequently been developed and tested using exposure tools. In this paper test results are shown using automated distortion correction. By analyzing the results, suggestions for further improvements and further developments are shown.

  5. Faster diffraction-based overlay measurements with smaller targets using 3D gratings

    Science.gov (United States)

    Li, Jie; Kritsun, Oleg; Liu, Yongdong; Dasari, Prasad; Volkman, Catherine; Hu, Jiangtao

    2012-03-01

    Diffraction-based overlay (DBO) technologies have been developed to address the overlay metrology challenges for 22nm technology node and beyond. Most DBO technologies require specially designed targets that consist of multiple measurement pads, which consume too much space and increase measurement time. The traditional empirical approach (eDBO) using normal incidence spectroscopic reflectometry (NISR) relies on linear response of the reflectance with respect to overlay displacement within a small range. It offers convenience of quick recipe setup since there is no need to establish a model. However it requires three or four pads per direction (x or y) which adds burden to throughput and target size. Recent advances in modeling capability and computation power enabled mDBO, which allows overlay measurement with reduced number of pads, thus reducing measurement time and DBO target space. In this paper we evaluate the performance of single pad mDBO measurements using two 3D targets that have different grating shapes: squares in boxes and L-shapes in boxes. Good overlay sensitivities are observed for both targets. The correlation to programmed shifts and image-based overlay (IBO) is excellent. Despite the difference in shapes, the mDBO results are comparable for square and L-shape targets. The impact of process variations on overlay measurements is studied using a focus and exposure matrix (FEM) wafer. Although the FEM wafer has larger process variations, the correlation of mDBO results with IBO measurements is as good as the normal process wafer. We demonstrate the feasibility of single pad DBO measurements with faster throughput and smaller target size, which is particularly important in high volume manufacturing environment.

  6. Simultaneous overlay and CD measurement for double patterning: scatterometry and RCWA approach

    Science.gov (United States)

    Li, Jie; Liu, Zhuan; Rabello, Silvio; Dasari, Prasad; Kritsun, Oleg; Volkman, Catherine; Park, Jungchul; Singh, Lovejeet

    2009-03-01

    As optical lithography advances to 32 nm technology node and beyond, double patterning technology (DPT) has emerged as an attractive solution to circumvent the fundamental optical limitations. DPT poses unique demands on critical dimension (CD) uniformity and overlay control, making the tolerance decrease much faster than the rate at which critical dimension shrinks. This, in turn, makes metrology even more challenging. In the past, multi-pad diffractionbased overlay (DBO) using empirical approach has been shown to be an effective approach to measure overlay error associated with double patterning [1]. In this method, registration errors for double patterning were extracted from specially designed diffraction targets (three or four pads for each direction); CD variation is assumed negligible within each group of adjacent pads and not addressed in the measurement. In another paper, encouraging results were reported with a first attempt at simultaneously extracting overlay and CD parameters using scatterometry [2]. In this work, we apply scatterometry with a rigorous coupled wave analysis (RCWA) approach to characterize two double-patterning processes: litho-etch-litho-etch (LELE) and litho-freeze-litho-etch (LFLE). The advantage of performing rigorous modeling is to reduce the number of pads within each measurement target, thus reducing space requirement and improving throughput, and simultaneously extract CD and overlay information. This method measures overlay errors and CDs by fitting the optical signals with spectra calculated from a model of the targets. Good correlation is obtained between the results from this method and that of several reference techniques, including empirical multi-pad DBO, CD-SEM, and IBO. We also perform total measurement uncertainty (TMU) analysis to evaluate the overall performance. We demonstrate that scatterometry provides a promising solution to meet the challenging overlay metrology requirement in DPT.

  7. Evaluation of Tizian overlays by means of a swept source optical coherence tomography system

    Science.gov (United States)

    Marcauteanu, Corina; Sinescu, Cosmin; Negrutiu, Meda Lavinia; Stoica, Eniko Tunde; Topala, Florin; Duma, Virgil Florin; Bradu, Adrian; Podoleanu, Adrian Gh.

    2016-03-01

    The teeth affected by pathologic attrition can be restored by a minimally invasive approach, using Tizian overlays. In this study we prove the advantages of a fast swept source (SS) OCT system in the evaluation of Tizian overlays placed in an environment characterized by high occlusal forces. 12 maxillary first premolars were extracted and prepared for overlays. The Tizian overlays were subjected to 3000 alternating cycles of thermo-cycling (from -10°C to +50°C) and to mechanical occlusal overloads (at 800 N). A fast SS OCT system was used to evaluate the Tizian overlays before and after the mechanical and thermal straining. The SS (Axsun Technologies, Billerica, MA) has a central wavelength of 1060 nm, sweeping range of 106 nm (quoted at 10 dB) and a 100 kHz line rate. The depth resolution of the system, measured experimentally in air was 10 μm. The imaging system used for this study offers high spatial resolutions in both directions, transversal and longitudinal of around 10 μm, a high sensitivity, and it is also able to acquire entire tridimensional (3D)/volume reconstructions as fast as 2.5 s. Once the full dataset was acquired, rendered high resolutions en-face projections could be produced. Using them, the overlay (i.e., cement) abutment tooth interfaces were remarked both on B-scans/two-dimensional (2D) sections and in the 3D reconstructions. Using the system several open interfaces were possible to detect. The fast SS OCT system thus proves useful in the evaluation of zirconia reinforced composite overlays, placed in an environment characterized by high occlusal forces.

  8. Using the overlay assay to qualitatively measure bacterial production of and sensitivity to pneumococcal bacteriocins.

    Science.gov (United States)

    Maricic, Natalie; Dawid, Suzanne

    2014-09-30

    Streptococcus pneumoniae colonizes the highly diverse polymicrobial community of the nasopharynx where it must compete with resident organisms. We have shown that bacterially produced antimicrobial peptides (bacteriocins) dictate the outcome of these competitive interactions. All fully-sequenced pneumococcal strains harbor a bacteriocin-like peptide (blp) locus. The blp locus encodes for a range of diverse bacteriocins and all of the highly conserved components needed for their regulation, processing, and secretion. The diversity of the bacteriocins found in the bacteriocin immunity region (BIR) of the locus is a major contributor of pneumococcal competition. Along with the bacteriocins, immunity genes are found in the BIR and are needed to protect the producer cell from the effects of its own bacteriocin. The overlay assay is a quick method for examining a large number of strains for competitive interactions mediated by bacteriocins. The overlay assay also allows for the characterization of bacteriocin-specific immunity, and detection of secreted quorum sensing peptides. The assay is performed by pre-inoculating an agar plate with a strain to be tested for bacteriocin production followed by application of a soft agar overlay containing a strain to be tested for bacteriocin sensitivity. A zone of clearance surrounding the stab indicates that the overlay strain is sensitive to the bacteriocins produced by the pre-inoculated strain. If no zone of clearance is observed, either the overlay strain is immune to the bacteriocins being produced or the pre-inoculated strain does not produce bacteriocins. To determine if the blp locus is functional in a given strain, the overlay assay can be adapted to evaluate for peptide pheromone secretion by the pre-inoculated strain. In this case, a series of four lacZ-reporter strains with different pheromone specificity are used in the overlay.

  9. Effect of Pre-oxidation on the Properties of Crushed Bituminous Coal and Activated Carbon Prepared Therefrom

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The influence of a pre-oxidation process on the chemical properties of crushed bituminous coal and on adsorption properties of the subsequently formed char and activated carbon is discussed in this paper.Datong bituminous coal samples sized 6 mm were oxidized at different temperatures and for different times and then carbonized and activated by steam to obtain activated carbons.A Uniform Design method was used to arrange the experiments, IR and adsorption experiments were used to characterize these oxidized coals, chars and activated carbon samples.The results show that the carboxyl group disappeared and α-CH2 groups joined to alkenes decreased dramatically but the carbonyl group clearly increased in the coal sample oxidized at 543 K; The chemical composition of coal samples oxidized at lower temperature is different from that of coal oxidized at 543 K.Oxidizing coal samples at higher temperatures for a short time or at lower temperatures for a longer time resulted in activated carbon samples that tended toward the same adsorption properties: Iodine number 1100 mg/g and Methylene blue value 252 mg/g.The yield of activated carbon obtained from the pre-oxidized coal is 10% higher than the yield from parent coal but the activated carbons have the same adsorption properties.

  10. Effect of Fe content on the friction and abrasion properties of copper base overlay on steel substrate by TIG welding

    Institute of Scientific and Technical Information of China (English)

    Lü Shixiong; Song Jianling; Liu Lei; Yang Shiqin

    2009-01-01

    Copper base alloy was overlaid onto 35CrMnSiA steel plate by tungsten inert gas (TIG) welding method. The heat transfer process was simulated, the microstructures of the copper base overlay were analyzed by scanning electron microscopy (SEM) and energy dispersive spectrometer (EDS), and the friction and abrasion properties of the overlay were measured. The results show that the Fe content increases in the overlay with increasing the welding current. And with the increase of Fe content in the overlay, the friction coefficient increases and the wear mechanism changes from oxidation wear to abrasive wear and plough wear, which is related to the size and quantity of Fe grains in the overlay. While with the increase of Fe content in the overlay, the protection of oxidation layer against the oxidation wear on the melted metal decreases.

  11. Study on the rupture characteristics of the overlaying soil with soft interlayer due to fault bedrock dislocation

    Institute of Scientific and Technical Information of China (English)

    ZHAO Lei; LI Xiao-jun; HUO Da

    2006-01-01

    In this paper, the rupture characteristics of the overlaying soil with soft interlayer were studied by plane-strain finite element method. From the results, it can be shown that the existence of soft layer separates rupture process of the overlaying soil into two phases. The depth of a buried soft interlayer will influence the rupture process and the rupture range of the overlaying soil. The deeply buried soft interlayer would bring about a wider range of surface failure. In addition, the thickness of the soft layer also has effect on the rupture process and rupture range of the overlaying soil.

  12. Desarrollo de sistemas y servicios de información sobre redes overlay peer-to-peer

    OpenAIRE

    Muñoz Gea, Juan Pedro

    2012-01-01

    [SPA] Una red overlay es una red virtual de nodos y enlaces lógicos construida sobre la red Internet. Por lo tanto, las redes overlay se pueden ver como una capa intermedia situad entre los protocolos básicos de Internet y el nivel de aplicación. Para entender por qué las redes overlay son importantes y el papel que desempeñan, merece la pena considerar las distintas razones que han motivado su aparición. En primer lugar, las redes overlay pueden utilizarse para soportar los requisitos especi...

  13. Desarrollo de sistemas y servicios de información sobre redes overlay peer-to-peer

    OpenAIRE

    Muñoz Gea, Juan Pedro

    2011-01-01

    [SPA] Una red overlay es una red virtual de nodos y enlaces lógicos construida sobre la red Internet. Por lo tanto, las redes overlay se pueden ver como una capa intermedia situad entre los protocolos básicos de Internet y el nivel de aplicación. Para entender por qué las redes overlay son importantes y el papel que desempeñan, merece la pena considerar las distintas razones que han motivado su aparición. En primer lugar, las redes overlay pueden utilizarse para soportar los requisitos especi...

  14. A Measurement Study of the Structured Overlay Network in P2P File-Sharing Systems

    Directory of Open Access Journals (Sweden)

    Mo Zhou

    2007-08-01

    Full Text Available The architecture of P2P file-sharing applications has been developing to meet the needs of large scale demands. The structured overlay network, also known as DHT, has been used in these applications to improve the scalability, and robustness of the system, and to make it free from single-point failure. We believe that the measurement study of the overlay network used in the real file-sharing P2P systems can provide guidance for the designing of such systems, and improve the performance of the system. In this paper, we perform the measurement in two different aspects. First, a modified client is designed to provide view to the overlay network from a single-user vision. Second, the instances of crawler programs deployed in many nodes managed to crawl the user information of the overlay network as much as possible. We also find a vulnerability in the overlay network, combined with the character of the DNS service, a more serious DDoS attack can be launched.

  15. Reduction of image-based ADI-to-AEI overlay inconsistency with improved algorithm

    Science.gov (United States)

    Chen, Yen-Liang; Lin, Shu-Hong; Chen, Kai-Hsiung; Ke, Chih-Ming; Gau, Tsai-Sheng

    2013-04-01

    In image-based overlay (IBO) measurement, the measurement quality of various measurement spectra can be judged by quality indicators and also the ADI-to-AEI similarity to determine the optimum light spectrum. However we found some IBO measured results showing erroneous indication of wafer expansion from the difference between the ADI and the AEI maps, even after their measurement spectra were optimized. To reduce this inconsistency, an improved image calculation algorithm is proposed in this paper. Different gray levels composed of inner- and outer-box contours are extracted to calculate their ADI overlay errors. The symmetry of intensity distribution at the thresholds dictated by a range of gray levels is used to determine the particular gray level that can minimize the ADI-to-AEI overlay inconsistency. After this improvement, the ADI is more similar to AEI with less expansion difference. The same wafer was also checked by the diffraction-based overlay (DBO) tool to verify that there is no physical wafer expansion. When there is actual wafer expansion induced by large internal stress, both the IBO and the DBO measurements indicate similar expansion results. The scanning white-light interference microscope was used to check the variation of wafer warpage during the ADI and AEI stages. It predicts a similar trend with the overlay difference map, confirming the internal stress.

  16. Diffraction-based overlay measurement on dedicated mark using rigorous modeling method

    Science.gov (United States)

    Lu, Hailiang; Wang, Fan; Zhang, Qingyun; Chen, Yonghui; Zhou, Chang

    2012-03-01

    Diffraction Based Overlay (DBO) is widely evaluated by numerous authors, results show DBO can provide better performance than Imaging Based Overlay (IBO). However, DBO has its own problems. As well known, Modeling based DBO (mDBO) faces challenges of low measurement sensitivity and crosstalk between various structure parameters, which may result in poor accuracy and precision. Meanwhile, main obstacle encountered by empirical DBO (eDBO) is that a few pads must be employed to gain sufficient information on overlay-induced diffraction signature variations, which consumes more wafer space and costs more measuring time. Also, eDBO may suffer from mark profile asymmetry caused by processes. In this paper, we propose an alternative DBO technology that employs a dedicated overlay mark and takes a rigorous modeling approach. This technology needs only two or three pads for each direction, which is economic and time saving. While overlay measurement error induced by mark profile asymmetry being reduced, this technology is expected to be as accurate and precise as scatterometry technologies.

  17. Overlay control methodology comparison: field-by-field and high-order methods

    Science.gov (United States)

    Huang, Chun-Yen; Chiu, Chui-Fu; Wu, Wen-Bin; Shih, Chiang-Lin; Huang, Chin-Chou Kevin; Huang, Healthy; Choi, DongSub; Pierson, Bill; Robinson, John C.

    2012-03-01

    Overlay control in advanced integrated circuit (IC) manufacturing is becoming one of the leading lithographic challenges in the 3x and 2x nm process nodes. Production overlay control can no longer meet the stringent emerging requirements based on linear composite wafer and field models with sampling of 10 to 20 fields and 4 to 5 sites per field, which was the industry standard for many years. Methods that have emerged include overlay metrology in many or all fields, including the high order field model method called high order control (HOC), and field by field control (FxFc) methods also called correction per exposure. The HOC and FxFc methods were initially introduced as relatively infrequent scanner qualification activities meant to supplement linear production schemes. More recently, however, it is clear that production control is also requiring intense sampling, similar high order and FxFc methods. The added control benefits of high order and FxFc overlay methods need to be balanced with the increased metrology requirements, however, without putting material at risk. Of critical importance is the proper control of edge fields, which requires intensive sampling in order to minimize signatures. In this study we compare various methods of overlay control including the performance levels that can be achieved.

  18. Design and development of a mobile image overlay system for needle interventions.

    Science.gov (United States)

    Anand, M; King, F; Ungi, T; Lasso, A; Rudan, J; Jayender, J; Fritz, J; Carrino, J A; Jolesz, F A; Fichtinger, G

    2014-01-01

    Previously, a static and adjustable image overlay systems were proposed for aiding needle interventions. The system was either fixed to a scanner or mounted over a large articulated counterbalanced arm. Certain drawbacks associated with these systems limited the clinical translation. In order to minimize these limitations, we present the mobile image overlay system with the objective of reduced system weight, smaller dimension, and increased tracking accuracy. The design study includes optimal workspace definition, selection of display device, mirror, and laser source. The laser plane alignment, phantom design, image overlay plane calibration, and system accuracy validation methods are discussed. The virtual image is generated by a tablet device and projected into the patient by using a beamsplitter mirror. The viewbox weight (1.0 kg) was reduced by 8.2 times and image overlay plane tracking precision (0.21 mm, STD = 0.05) was improved by 5 times compared to previous system. The automatic self-calibration of the image overlay plane was achieved in two simple steps and can be done away from patient table. The fiducial registration error of the physical phantom to scanned image volume registration was 1.35 mm (STD = 0.11). The reduced system weight and increased accuracy of optical tracking should enable the system to be hand held by the physician and explore the image volume over the patient for needle interventions.

  19. Image-based overlay (IBO) target segment design on self-aligned patterning process

    Science.gov (United States)

    Ye, Lei; Hu, Huayong; He, Weiming

    2016-03-01

    Self-Aligned Double Patterning (SADP) is widely applied in advanced sub-4X patterning technology, especially for the 1D resolution shrinkage of memory technology. As the application of SADP makes lithography minimum pitch down to half of design pitch with the remaining spacer aside core, its alignment mark and overlay (OVL) mark have to be well-segmented to ensure enough mark contrast. In this paper, we designed two types of image-based overlay (IBO) bar in bar (BIB) OVL target: bar-segmentation and background-segmentation with different duty ratio. Based on these two designed types of marks, we focus on the OVL of 2nd photo layer to 1st SADP layer with the core removed (which means spacer grating structure remained). We studied the effect of the overlay target segmentation on the precision and robustness of wafer-level overlay performance. Different lithography processes were also studied, including single layer lithography and tri-layer lithography with planarized spacer grating structures. We found there are strong correlations between overlay measurement accuracy and background segmentation rules. The results of our study will be presented and discussed in this paper.

  20. Implementation and benefits of advanced process control for lithography CD and overlay

    Science.gov (United States)

    Zavyalova, Lena; Fu, Chong-Cheng; Seligman, Gary S.; Tapp, Perry A.; Pol, Victor

    2003-05-01

    Due to the rapidly reduced imaging process windows and increasingly stingent device overlay requirements, sub-130 nm lithography processes are more severely impacted than ever by systamic fault. Limits on critical dimensions (CD) and overlay capability further challenge the operational effectiveness of a mix-and-match environment using multiple lithography tools, as such mode additionally consumes the available error budgets. Therefore, a focus on advanced process control (APC) methodologies is key to gaining control in the lithographic modules for critical device levels, which in turn translates to accelerated yield learning, achieving time-to-market lead, and ultimately a higher return on investment. This paper describes the implementation and unique challenges of a closed-loop CD and overlay control solution in high voume manufacturing of leading edge devices. A particular emphasis has been placed on developing a flexible APC application capable of managing a wide range of control aspects such as process and tool drifts, single and multiple lot excursions, referential overlay control, 'special lot' handling, advanced model hierarchy, and automatic model seeding. Specific integration cases, including the multiple-reticle complementary phase shift lithography process, are discussed. A continuous improvement in the overlay and CD Cpk performance as well as the rework rate has been observed through the implementation of this system, and the results are studied.

  1. Information Exchange rather than Topology Awareness: Cooperation between P2P Overlay and Traffic Engineering

    Directory of Open Access Journals (Sweden)

    Jia Zhao

    2014-01-01

    Full Text Available Solutions to the routing strategic conflict between noncooperative P2P overlay and ISP underlay go separate ways: hyperselfishness and cooperation. Unpredictable (possibly adverse impact of the hyperselfish topology awareness, which is adopted in both overlay routing and traffic engineering, has not been sufficiently studied in the literature. Topology-related information exchange in a cooperatively efficient way should be highlighted to alleviate the cross-layer conflict. In this paper, we first illustrate the hyperselfish weakness with two dynamic noncooperative game models in which hyperselfish overlay or underlay has to accept a suboptimal profit. Then we build a synergistic cost-saving (SC game model to reduce the negative effects of noncooperation. In the SC model, through information exchange, that is, the classified path-delay metrics for P2P overlay and peer locations for underlay, P2P overlay selects proximity as well as saving traffic transit cost for underlay, and ISP underlay adjusts routing to optimize network cost as well as indicating short delay paths for P2P. Simulations based on the real and generated topologies validate cost improvement by SC model and find a proper remote threshold value to limit P2P traffic from remote area, cross-AS, or cross-ISP.

  2. On the Degree Distribution of Faulty Peer-to-Peer Overlays

    CERN Document Server

    Ferretti, Stefano

    2011-01-01

    This paper presents an analytical framework to model fault-tolerance in unstructured peer-to-peer overlays, represented as complex networks. We define a distributed protocol peers execute for managing the overlay and reacting to node faults. Based on the protocol, evolution equations are defined and manipulated by resorting to generating functions. Obtained outcomes provide insights on the nodes' degree probability distribution. From the study of the degree distribution, it is possible to estimate other important metrics of the peer-to-peer overlay, such as the diameter of the network. We study different networks, characterized by three specific desired degree distributions, i.e. nets with nodes having a fixed desired degree, random graphs and scale-free networks. All these networks are assessed via the analytical tool and simulation as well. Results show that the approach can be factually employed to dynamically tune the average attachment rate at peers so that they maintain their own desired degree and, in ...

  3. Refractometric sensor utilizing a vertically coupled polymeric microdisk resonator incorporating a high refractive index overlay.

    Science.gov (United States)

    Kim, Gun-Duk; Son, Geun-Sik; Lee, Hak-Soon; Kim, Ki-Do; Lee, Sang-Shin

    2009-04-01

    A refractometric sensor resorting to a vertically coupled polymeric microdisk resonator was demonstrated, estimating the refractive index (RI) of an analyte by monitoring the resonant wavelength shift in its transfer characteristics. The disk resonator was especially overlaid with a high RI TiO2 film, thereby reinforcing the interaction of the evanescent field of its guided mode with the analyte. The sensitivity of the sensor was theoretically and experimentally confirmed to be enhanced by adjusting the overlay thickness. The fabricated sensor provided the maximum sensitivity of approximately 294 nm/RIU (refractive index unit) with the 40-nm-thick overlay, which is equivalent to an improvement of 150% compared with the case without the overlay.

  4. Study on cracking of welding overlay based on the theory of diffusion-induced stress

    Institute of Scientific and Technical Information of China (English)

    Xiliang ZHANG; Changyu ZHOU

    2011-01-01

    Hydrogen diffusion in the wall of hydrogenation reactor for three situations,i.e. operating,normal shutdown and abnormal shutdown,was numerically simulated based on the finite element program-ABAQUS. The formula of diffusion-induced stress was deduced for model of the thin walled cylinder. Distribution of diffusion-induced stress in the wall of hydrogenation reactor was studied. The results showed that the maximum stress was at the fusion surface between welding overlay and base metal,and which would increase with cooling rate. The crack will initiate and propagate from fusion surface to welding overlay when the diffusion-induced stress is higher than yield stress,but it will not propagate to the base metal. Diffusion-induced stress is one of the important factors for crack initiation and propagation of welding overlay of hydrogenation reactor.

  5. 基于SDN架构的Overlay VPN技术研究

    Institute of Scientific and Technical Information of China (English)

    张鹏; 孙琼

    2016-01-01

    首先介绍基于SDN架构的Overlay VPN技术,能为中小企业提供低成本、高性能、易使用、安全的VPN服务.Overlay VPN预先在网络中部署中间转发节点vPE,集中式控制器通过智能选路算法,为用户提供有保障的VPN服务.此外,分析Overlay VPN的架构、控制平面和数据平面的流程,并提出若干优化的方向.

  6. Maxillary overlay removable partial dentures for the restoration of worn teeth.

    Science.gov (United States)

    Fonseca, Júlio; Nicolau, Pedro; Daher, Tony

    2011-04-01

    Prolonged tooth maintenance by a more aged population considerably increases the probability of dentists having to treat patients with high levels of tooth wear. Pathological tooth wear, caused primarily by parafunction, seems to be a growing problem that affects a large number of adult patients. The clinical report presents a case of a partially edentulous patient with an elevated degree of wear in the upper jaw caused by attrition and erosion, rehabilitated with a maxillary overlay removable partial denture (ORPD) consisting of a chrome-cobalt (Cr-Co) framework with anterior acrylic resin veneers, posterior cast overlays, and acrylic resin denture bases. Removable partial prosthesis is a treatment alternative when teeth are found to be severely worn or when the patient needs a simple and economical option. Because economics is a conditional factor of the treatment, the clinician should present different treatment alternatives to the patient, in which the overlay prosthesis can be considered.

  7. Streaming Media over a Color Overlay Based on Forward Error Correction Technique

    Institute of Scientific and Technical Information of China (English)

    张晓瑜; 沈国斌; 李世鹏; 钟玉琢

    2004-01-01

    The number of clients that receive high-quality streaming video from a source is greatly limited by the application requirements,such as the high bandwidth and reliability.In this work,a method was developed to construct a color overlay,which enables clients to receive data across multiple paths,based on the forward error correction technique.The color overlay enlarges system capacity by reducing the bottlenecks and extending the bandwidth,improves reliability against node failure,and is more resilient to fluctuations of network metrics.A light-weight protocol for building the overlay is also presented.Extensive simulations were conducted and the results clearly support the claimed advantages.

  8. Topology-aware peer-to-peer overlay network for Ad-hoc

    Institute of Scientific and Technical Information of China (English)

    WANG Shi-guo; JI Hong; LI Ting; MEI Jing-qing

    2009-01-01

    The mismatch between the structured peer-to-peer (P2P) overlay network, which is based on Hashing, and the actual physical network, leads to query repeatedly passing through some nodes in the actual route when it is applied in Ad-hoc networks. An approach of getting an appropriate node identifier (ID) bearing its local physical information is proposed, in which the traditional theory of getting node ID through Hashing the node's Internet protocol (IP) address is abandoned, and a topology-aware overlay network suiting Ad-hoc networks is constructed. The simulation results show that the overlay network constructed in the proposed method can avoid the route being iteratively accessed. Meanwhile, it can effectively minimize the latency and improve the load balance.

  9. Laser-induced desorption of overlayer films off a heated metal substrate

    Science.gov (United States)

    Gu, Xiang; Urbassek, Herbert M.

    2007-02-01

    The temperature-induced desorption of adsorbed overlayer films with thicknesses between 4 and 200 ML off a suddenly heated metal substrate is studied using molecular-dynamics simulation. We observe that the rapid heating vaporizes the surface-near part of the overlayer film. The initial heating-induced thermoelastic pressure and the vapor pressure in the vapor film drive the remaining film as a large relatively cold cluster away from the surface. In our simulations, the material present in the developing vapor film amounts to roughly 2 ML and is quite independent of the overlayer film thickness. For cluster thicknesses beyond 40 ML, the desorption time increases only little with film thickness, while the resulting cluster velocity decreases only slightly.

  10. Petrography and geochemistry of Oligocene bituminous coal from the Jiu Valley, Petrosani basin (southern Carpathian Mountains), Romania

    Energy Technology Data Exchange (ETDEWEB)

    Belkin, Harvey E.; Tewalt, Susan J. [U.S. Geological Survey, 956 National Center, Reston, VA 20192 (United States); Hower, James C. [University of Kentucky Center for Applied Energy Research, 2540 Research Park Drive, Lexington, KY 40511 (United States); Stucker, J.D. [University of Kentucky Center for Applied Energy Research, 2540 Research Park Drive, Lexington, KY 40511 (United States); University of Kentucky Department of Earth and Environmental Sciences, Lexington, KY 40506 (United States); O' Keefe, Jennifer M.K. [Morehead State University, Morehead, KY, 40351 (United States); Tatu, Calin A. [University of Medicine and Pharmacy, Department of Immunology, Clinical Laboratory No. 1, Pta. E. Murgu No. 2, RO-1900 Timisoara (Romania); Buia, Grigore [University of Petrosani, Department of Geology, University St. 20, RO-2675 Petrosani (Romania)

    2010-05-01

    Belt samples of Oligocene (Chattian) bituminous coal from 10 underground mines located in the Jiu Valley, Hunedoara County, Petrosani basin, Romania, have been examined and analyzed for proximate and ultimate analysis, major-, minor- and trace-element chemistry, organic petrography, and vitrinite reflectance. The mineral chemistry and mode of occurrence of trace elements also have been investigated using SEM and electron microprobe techniques. Twenty coal beds occur in the Jiu Valley and most of the samples are from bed no. 3, the most productive bed of the Dilja-Uricani Formation of Oligocene age. The Petrosani basin, oriented SW-NE, is 48-km long, 10-km wide at the eastern part and 2-km wide at the western part. The coal mines are distributed along the center of the valley generally following the Jiu de Vest River. Reflectance measurements indicate that the rank of the coals ranges from high-volatile B to high-volatile A bituminous. Overall, rank decreases from the southwest to the northeast. In bed no. 3, R{sub max} varies from 0.75% in the northeast to 0.93% in the southwest. Although, most Oligocene coals in Romania and adjacent countries are lignite in rank, the Jiu Valley bituminous coals have been affected by regional metamorphism and attending hydrothermal fluids related to the Alpine orogenic event. The coals are all dominated by vitrinite; resinite and funginite are important minor macerals in most of the coals. Pyrite and carbonate generally dominate the mineral assemblages with carbonate more abundant in the northwest. Siderite occurs as nodules and masses within the macerals (generally vitrinite). Dolomite and calcite occur as fracture fillings, plant-cell fillings, and in other authigenic forms. Late-stage fracture fillings are siderite, dolomite, calcite, and ankerite. In one instance, two populations of siderite ({proportional_to} 35 and {proportional_to} 45 wt.% FeO) plus ankerite fill a large fracture. Late-stage pyrite framboid alteration is Ni

  11. Impact of reticle writing errors on the on-product overlay performance

    Science.gov (United States)

    van Haren, Richard; Cekli, Hakki Ergun; Liu, Xing Lan; Beltman, Jan; Pastol, Anne; Massin, Jean; Dupre La Tour, Emilie; Gatefait, Maxime; Sundermann, Frank

    2014-10-01

    The on-product overlay specification and Advanced Process Control (APC) are getting extremely challenging particularly after the introduction of multi-patterning applications like Litho-Etch-Litho-Etch (LELE). While the Reticle Writing Error (RWE) contribution could be marginalized for quite some time in the layer-to-layer overlay budget, it will become one of the dominating overlay contributors when the intra-layer overlay budget is considered. While most of the overlay contributors like wafer processing, scanner status, reticle transmission, dose, illumination conditions drop out of the intra-layer overlay budget, this is certainly not the case for reticle to reticle writing differences. In this work, we have studied the impact of the RWE on the on-product overlay performance. We show that the RWE can be characterized by an off-line mask registration tool and the modelled results can be sent as feed-forward corrections to the ASML TWINSCANTM. By doing so, the overlay control complexity (e.g. send-ahead wafers, APC settling time) can be reduced significantly. Off-line characterization enables that all reticles virtually become equal after correction (at least to the level of correction capability of the scanner). This means that all higher order RWE contributions (currently up to a third order polynomial) can be removed from the fingerprint. We show that out of 50 production reticles (FEOL, 28-nm technology), 30% can be improved on residual level when non-linear feed-forward corrections are considered as well. The additional benefit of feeding forward linear corrections to the scanner is even higher: it is anticipated that a large portion of the APC variation might find its origin in the RWE contribution. In order to send feed-forward corrections to the scanner, we obviously rely on the quality of the off-line RWE measurements. These measurements are usually provided by a registration tool at the mask shop. To secure the quality, an independent experimental

  12. Detection of overlay error in double patterning gratings using phase-structured illumination.

    Science.gov (United States)

    Peterhänsel, Sandy; Gödecke, Maria Laura; Paz, Valeriano Ferreras; Frenner, Karsten; Osten, Wolfgang

    2015-09-21

    With the help of simulations we study the benefits of using coherent, phase-structured illumination to detect the overlay error in resist gratings fabricated by double patterning. Evaluating the intensity and phase distribution along the focused spot of a high numerical aperture microscope, the capability of detecting magnitude and direction of overlay errors in the range of a few nanometers is investigated for a wide range of gratings. Furthermore, two measurement approaches are presented and tested for their reliability in the presence of white Gaussian noise.

  13. A New Approach to Assess the Positional Accuracy of Maps Generated by GIS Overlay Operations

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    This paper proposes a new approach to assess the positional accuracy of maps generated by overlaying multi-scale spatial data layers with different levels of positional accuracy.The existing techniques for assessing the positional accuracy of point,line and polygon features is first examined.Then a taxonomy of graphic features on the derived maps is developed by analyzing the specific processes of overlay operations.Finally,a detailed description of the new approach is provided and the implementation of this new method in practical applications is described.

  14. Studying protein-protein interactions via blot overlay/far western blot.

    Science.gov (United States)

    Hall, Randy A

    2015-01-01

    Blot overlay is a useful method for studying protein-protein interactions. This technique involves fractionating proteins on SDS-PAGE, blotting to nitrocellulose or PVDF membrane, and then incubating with a probe of interest. The probe is typically a protein that is radiolabeled, biotinylated, or simply visualized with a specific antibody. When the probe is visualized via antibody detection, this technique is often referred to as "Far Western blot." Many different kinds of protein-protein interactions can be studied via blot overlay, and the method is applicable to screens for unknown protein-protein interactions as well as to the detailed characterization of known interactions.

  15. Super-proximity routing in structured peer-to-peer overlay networks

    Institute of Scientific and Technical Information of China (English)

    WU Zeng-de(吴增德); RAO Wei-xiong(饶卫雄); MA Fan-yuan(马范援)

    2004-01-01

    Peer-to-Peer systems are emerging as one of the most popular Internet applications. Structured Peer-to-Peer overlay networks use identifier based routing algorithms to allow robustness, load balancing, and distributed lookup needed in this environment. However, identifier based routing that is independent of Internet topology tends to be of low efficiency. Aimed at improving the routing efficiency, the super-proximity routing algorithms presented in this paper combine Internet topology and overlay routing table in choosing the next hop. Experimental results showed that the algorithms greatly improve the efficiency of Peer-to-Peer routing.

  16. Combustion characteristics of Malaysian oil palm biomass, sub-bituminous coal and their respective blends via thermogravimetric analysis (TGA).

    Science.gov (United States)

    Idris, Siti Shawalliah; Rahman, Norazah Abd; Ismail, Khudzir

    2012-11-01

    The combustion characteristics of Malaysia oil palm biomass (palm kernel shell (PKS), palm mesocarp fibre (PMF) and empty fruit bunches (EFB)), sub-bituminous coal (Mukah Balingian) and coal/biomass blends via thermogravimetric analysis (TGA) were investigated. Six weight ratios of coal/biomass blends were prepared and oxidised under dynamic conditions from temperature 25 to 1100°C at four heating rates. The thermogravimetric analysis demonstrated that the EFB and PKS evolved additional peak besides drying, devolatilisation and char oxidation steps during combustion. Ignition and burn out temperatures of blends were improved in comparison to coal. No interactions were observed between the coal and biomass during combustion. The apparent activation energy during this process was evaluated using iso-conversional model free kinetics which resulted in highest activation energy during combustion of PKS followed by PMF, EFB and MB coal. Blending oil palm biomass with coal reduces the apparent activation energy value.

  17. Fixed-bed gasification research using US coals. Volume 8. Gasification of River King Illinois No. 6 bituminous coal

    Energy Technology Data Exchange (ETDEWEB)

    Thimsen, D.; Maurer, R.E.; Pooler, A.R.; Pui, D.; Liu, B.; Kittelson, D.

    1985-05-01

    A single-staged, fixed-bed Wellman-Galusha gasifier coupled with a hot, raw gas combustion system and scrubber has been used to gasify numerous coals from throughout the United States. The gasification test program is organized as a cooperative effort by private industrial participants and governmental agencies. The consortium of participants is organized under the Mining and Industrial Fuel Gas (MIFGa) Group. This report is the eighth volume in a series of reports describing the atmospheric pressure, fixed-bed gasification of US coals. This specific report describes the gasification of River King Illinois No. 6 bituminous coal. The period of gasification test was July 28 to August 19, 1983. 6 refs., 23 figs., 25 tabs.

  18. Organic petrology and geochemistry of Eocene Suzak bituminous marl, north-central Afghanistan: Depositional environment and source rock potential

    Science.gov (United States)

    Hackley, Paul C.; Sanfilipo, John

    2016-01-01

    Organic geochemistry and petrology of Eocene Suzak bituminous marl outcrop samples from Madr village in north-central Afghanistan were characterized via an integrated analytical approach to evaluate depositional environment and source rock potential. Multiple proxies suggest the organic-rich (TOC ∼6 wt.%) bituminous marls are ‘immature’ for oil generation (e.g., vitrinite Ro rock sulfur content is ∼2.3 wt.% whereas sulfur content is ∼5.0–5.6 wt.% in whole rock extracts with high polar components, consistent with extraction from S-rich Type IIs organic matter which could generate hydrocarbons at low thermal maturity. Low Fe-sulfide mineral abundance and comparison of Pr/Ph ratios between saturate and whole extracts suggest limited Fe concentration resulted in sulfurization of organic matter during early diagenesis. From these observations, we infer that a Type IIs kerogen in ‘immature’ bituminous marl at Madr could be generating high sulfur viscous oil which is seeping from outcrop. However, oil-seep samples were not collected for correlation studies. Aluminum-normalized trace element concentrations indicate enrichment of redox sensitive trace elements Mo, U and V and suggest anoxic-euxinic conditions during sediment deposition. The bulk of organic matter observed via optical microscopy is strongly fluorescent amorphous bituminite grading to lamalginite, possibly representing microbial mat facies. Short chain n-alkanes peak at C14–C16 (n-C17/n-C29 > 1) indicating organic input from marine algae and/or bacterial biomass, and sterane/hopane ratios are low (0.12–0.14). Monoaromatic steroids are dominated by C28clearly indicating a marine setting. High gammacerane index values (∼0.9) are consistent with anoxia stratification and may indicate intermittent saline-hypersaline conditions. Stable C isotope ratios also suggest a marine depositional scenario for the Suzak samples, consistent with the presence of marine foraminifera including

  19. Study on co-pyrolysis characteristics of rice straw and Shenfu bituminous coal blends in a fixed bed reactor.

    Science.gov (United States)

    Li, Shuaidan; Chen, Xueli; Liu, Aibin; Wang, Li; Yu, Guangsuo

    2014-03-01

    Co-pyrolysis behaviors of rice straw and Shenfu bituminous coal were studied in a fixed bed reactor under nitrogen atmosphere. The pyrolysis temperatures were 700°C, 800°C and 900°C, respectively. Six different biomass ratios were used. Gas, tar components were analyzed by a gas chromatograph and a gas chromatography-mass spectrometry respectively. Under co-pyrolysis conditions, the gas volume yields are higher than the calculated values. Co-pyrolysis tar contains more phenolics, less oxygenate compounds than calculated values. The addition of biomass changes the atmosphere during the pyrolysis process and promotes tar decomposition. The SEM results show that the differences between the blended char and their parents char are not significant. The results of char yields and ultimate analysis also show that no significant interactions exist between the two kinds of particles. The changes of gas yield and components are caused by the secondary reactions and tar decomposition.

  20. Evaluation of bituminous materials used in pavement recycling projects at Tyndall, MacDill, and Hurlburt Air Force Bases

    Science.gov (United States)

    Kiggundu, B.; Martinez, R.; Humphrey, B.; Shuler, T.

    1987-07-01

    This report presents results of a study involving bituminous materials from Tyndall and MacDill Air Force Bases and Hurlburt Field. These materials included Reclaimed Asphalt Pavement (RAP), modifiers, virgin asphalts, and new aggregates. A tentative modifier selection criterion was used to judge the quality of materials used in the recycling efforts at the respective sites. The results showed that independent adequacy of physical properties from chemical properties in selection of modifiers could not be established. However, some of the results showed that physical properties were more sensitive indicators of changes in binders due to aging. In addition, this report includes the tentative modifier selection criteria and results of an interlaboratory study from which variability limits to parameters determined using modified Clay-Gel and Heithaus procedures are established. The modified Clay-Gel and Heithaus procedures are included.

  1. Structural characterization of vitrinite-rich and inertinite-rich Permian-aged South African bituminous coals

    Energy Technology Data Exchange (ETDEWEB)

    Van Niekerk, Daniel; Mathews, Jonathan P. [Energy and Mineral Engineering and the EMS Energy Institute, Pennsylvania State University, Hosler Building, University Park, PA 16802 (United States); Pugmire, Ronald J. [Department of Chemical Engineering, University of Utah, Salt Lake City, Utah 84112 (United States); Department of Chemistry, University of Utah, Salt Lake City, Utah 84112 (United States); Solum, Mark S. [Department of Chemistry, University of Utah, Salt Lake City, Utah 84112 (United States); Painter, Paul C. [Department of Materials Science and Engineering, Pennsylvania State University, 320 Steidle Building, University Park, PA 16802 (United States)

    2008-12-01

    Two South African coals of the same rank and age, but different in maceral composition were subjected to extensive structural analyses. Inertinite-rich Highveld coal (dominated by semifusinite) and vitrinite-rich Waterberg coal were studied to determine structural differences and similarities. The two coals had similar carbon content ({proportional_to} 84%, dmmf) and vitrinite reflectance (mean-maximum 0.71% for vitrinite-rich vs. 0.75% for inertinite-rich), but differed in hydrogen content (6.23% for vitrinite-rich and 4.53% for inertinite-rich). The inertinite-rich coal was more aromatic (86% for inertinite-rich and 76% for vitrinite-rich) and more polycondensed (indicated by a higher bridgehead carbon content). The inertinite-rich coal was structurally more ordered, with a higher degree of crystalline stacking. Both coals had similar average aromatic cluster sizes (16 carbons for vitrinite-rich and 18 carbons for inertinite-rich) and number of cluster attachments (6 attachments for vitrinite-rich and 5 attachments for inertinite-rich). Mass spectrometry showed that both coals consist of similar molecular weight distributions; ranging to approximately 1700 m/z with a maximum abundance of {proportional_to} 450 m/z for the vitrinite-rich coal and {proportional_to} 550 m/z for the inertinite-rich coal. Compared to the Argonne Premium coals the South African vitrinite-rich Waterberg coal was comparable to the coals in the high-volatile bituminous range and inertinite-rich Highveld was closer to the medium- to low-volatile bituminous range. Both coals were surprisingly similar in bulk characterization, although inertinite-rich Highveld coal was structurally more ordered, hydrogen deficient, and more aromatic. (author)

  2. Improved Intelligent Underlay-Overlay Combined with Frequency Hopping in GSM

    DEFF Research Database (Denmark)

    Wigard, Jeroen; Nielsen, Thomas Toftegaard; Mogensen, Preben Elgaard

    1997-01-01

    IUO (intelligent underlay-overlay) in a combination with random frequency hopping in GSM is analysed. Several improvements to the original IUO concept analysed in Nielsen et al. (1997) are introduced. With the improved IUO concept it is possible to load a network configuration consisting of 4 reg...

  3. Interactive overlay maps for US Patent (USPTO) data based on International Patent Classifications (IPC)

    NARCIS (Netherlands)

    L. Leydesdorff; D. Kushnir; I. Rafols

    2014-01-01

    We report on the development of an interface to the US Patent and Trademark Office (USPTO) that allows for the mapping of patent portfolios as overlays to basemaps constructed from citation relations among all patents contained in this database during the period 1976-2011. Both the interface and the

  4. Arbitration Intervention Worker (AIW) Services: Case Management Overlay in a Juvenile Diversion Program

    Science.gov (United States)

    Poythress, Norman G.; Dembo, Richard; DuDell, Gary; Wareham, Jennifer

    2006-01-01

    In this issue we describe a clinical trials study of the impact of adding specific case manager overlay services to "treatment as usual" services for youths in a Juvenile Arbitration Program. In this first article we describe the experimental intervention, the Arbitration Intervention Worker (AIW) service, which was provided to a randomly selected…

  5. A study and simulation of the impact of high-order aberrations to overlay error distribution

    Science.gov (United States)

    Sun, G.; Wang, F.; Zhou, C.

    2011-03-01

    With reduction of design rules, a number of corresponding new technologies, such as i-HOPC, HOWA and DBO have been proposed and applied to eliminate overlay error. When these technologies are in use, any high-order error distribution needs to be clearly distinguished in order to remove the underlying causes. Lens aberrations are normally thought to mainly impact the Matching Machine Overlay (MMO). However, when using Image-Based overlay (IBO) measurement tools, aberrations become the dominant influence on single machine overlay (SMO) and even on stage repeatability performance. In this paper, several measurements of the error distributions of the lens of SMEE SSB600/10 prototype exposure tool are presented. Models that characterize the primary influence from lens magnification, high order distortion, coma aberration and telecentricity are shown. The contribution to stage repeatability (as measured with IBO tools) from the above errors was predicted with simulator and compared to experiments. Finally, the drift of every lens distortion that impact to SMO over several days was monitored and matched with the result of measurements.

  6. An Efficient Method for Performance Evaluation of Femto-Macro Overlay Systems

    DEFF Research Database (Denmark)

    Huang, Yue-Cai; Ko, King-Tim; Huang, Qian;

    2011-01-01

    This paper considers a two-tier femto-macro overlay network architecture, where groups of femtocells are overlaid by macrocells. The capacity of the femtocells is limited, thus redirection of blocked femto calls to the overlaid macrocell is used as a QoS assurance strategy. Similar overflow appro...

  7. Robotic weld overlay coatings for erosion control. Final technical progress report, July 1992--July 1995

    Energy Technology Data Exchange (ETDEWEB)

    Levin, B.F.; DuPont, J.N.; Marder, A.R.

    1995-10-15

    The erosion behavior of weld overlay coatings has been studied. Eleven weld overlay alloys were deposited on 1018 steel substrates using the plasma arc welding process and erosion tested at 400{degrees}C at 90{degrees} and 30{degrees} particle impact angles. The microstructure of each coating was characterized before erosion testing. A relative ranking of the coatings erosion resistance was developed by determining the steady state erosion rates. Ultimet, Inconel-625, and 316L SS coatings showed the best erosion resistance at both impact angles. It was found that weld overlays that exhibit good abrasion resistance did not show good erosion resistance. Erosion tests were also performed for selected wrought materials with chemical composition similar to weld overlays. Eroded surfaces of the wrought and weld alloys were examined by Scanning Electron Microscopy (SEM). Microhardness tests were performed on the eroded samples below the erosion surface to determine size of the plastically deformed region. It was found that one group of coatings experienced significant plastic deformation as a result of erosion while the other did not. It was also established that, in the steady state erosion regime, the size of the plastically deformed region is constant.

  8. Frenkel-Kontorova Model of the Dimerized Overlayer System with Vacancies

    Institute of Scientific and Technical Information of China (English)

    XU Hai-Bo; WANG Guang-Rui; CHEN Shi-Gang

    2000-01-01

    The reconstruction of the dimerized overlayer system with vacancies is studied via a diatomic chain Frenkel Kontorova model. We present the details of the exactly solvable model and the analytical solution of the atomic displacements in the ground state. Our calculations explain the 2 × N reconstruction observed in Ge/Si(100) and Ga/Si(112).

  9. Effect of oil overlay on inhibition potential of roscovitine in sheep cumulus-oocyte complexes.

    Science.gov (United States)

    Crocomo, L F; Marques Filho, W C; Ulian, C M V; Branchini, N S; Silva, D T; Ackermann, C L; Landim-Alvarenga, F C; Bicudo, S D

    2015-06-01

    Inhibitors of cyclin-dependent kinases, as roscovitine, have been used to prevent the spontaneous resumption of meiosis in vitro and to improve the oocyte developmental competence. In this study, the interference of oil overlay on the reversible arrest capacity of roscovitine in sheep oocytes as well as its effects on cumulus expansion was evaluated. For this, cumulus-oocyte complexes (COCs) were cultured for 20 h in TCM 199 with 10% foetal bovine serum (Control) containing 75 μm roscovitine (Rosco). Subsequently, they were in vitro matured (IVM) for further 18 h in inhibitor-free medium with LH and FSH. The culture was performed in Petri dishes under mineral oil (+) or in 96 well plates without oil overlay (-) at 38.5°C and 5% CO2 . At 20 and 38 h, the cumulus expansion and nuclear maturation were evaluated under stereomicroscope and by Hoechst 33342 staining, respectively. No group presented cumulus expansion at 20 h. After additional culture with gonadotrophins, a significant rate of COCs from both Control groups (+/-) exhibited total expansion while in both Rosco groups (+/-) the partial expansion prevailed. Among the oocytes treated with roscovitine, 65.2% were kept at GV in the absence of oil overlay while 40.6% of them reached MII under oil cover (p overlay improved the meiotic inhibition promoted by roscovitine without affecting the cumulus expansion rate or the subsequent meiosis progression.

  10. Colored Overlays Enhance Visual Perceptual Performance in Children with Autism Spectrum Disorders

    Science.gov (United States)

    Ludlow, A. K.; Wilkins, A. J.; Heaton, P.

    2008-01-01

    Children with autism spectrum disorders (ASD), together with controls matched for age and ability participated in three experiments that assessed the therapeutic benefit of colored overlays. The findings from the first experiment showed that a significantly greater proportion of children with ASD, than controls, increased reading speed when using…

  11. Assessing the Crossdisciplinarity of Technology-Enhanced Learning with Science Overlay Maps and Diversity Measures

    Science.gov (United States)

    Kalz, Marco; Specht, Marcus

    2014-01-01

    This paper deals with the assessment of the crossdisciplinarity of technology-enhanced learning (TEL). Based on a general discussion of the concept interdisciplinarity and a summary of the discussion in the field, two empirical methods from scientometrics are introduced and applied. Science overlay maps and the Rao-Stirling diversity index are…

  12. Maxillary and mandibular overlay removable partial dentures for the restoration of worn teeth.

    Science.gov (United States)

    Ganddini, Mario R; Al-Mardini, Majd; Graser, Gerald N; Almog, Dov

    2004-03-01

    This clinical report describes the fabrication of maxillary and mandibular cast overlay removable partial dentures for the restoration of severely worn teeth with accompanying loss of vertical dimension of occlusion. The frameworks supported porcelain veneers for esthetics and metal occlusal surfaces for strength and durability.

  13. A Novel Approach to Overlay Multicasting Schemes for Multi-Hop Ad-Hoc Networks

    Science.gov (United States)

    Kang, Namhi; Oh, Jejun; Kim, Younghan

    Multicast is an efficient transport mechanism for group-based community communications and mobile ad-hoc networks (MANET) is recently regarded as a promising solution for supporting ubiquitous computing as an underlying network technology. However, it is challenging to deploy the multicast mechanism used in a wired network directly into MANET owing to scarce resources in wireless networks and unpredictable changes in network topology. Several multicast mechanisms have been proposed in the literature to overcome these limitations. In MANET, especially, overlay multicasting schemes present several advantages over network-based multicasting schemes. However we have observed a common limitation of previously proposed overlay multicasting schemes. They introduce redundant data transmissions that waste network bandwidth and the battery of relay nodes. The observation motivated us to propose an efficient way to create and maintain a “semi-overlay structure” that utilizes a few nonmember nodes selected as branch nodes. The proposed scheme, called “SOMRP (Semi-overlay multicast routing protocol),” has been evaluated by using extensive network simulation in two different scenarios, comparing the performance of SOMRP with two previously proposed schemes. Simulation results show that SOMRP outperforms the two schemes in terms of the packet delivery ratio, transmission cost and end-to-end delay.

  14. Gossip-Based Topology Management Protocol for Self-Organizing Overlays

    Institute of Scientific and Technical Information of China (English)

    Chen Nao; Hu Ruimin; Zhu Yongqiong

    2011-01-01

    Gossip-based protocols have attracted more and more attention because of their simplicity and reliability.They can be applied to large-scale overlays for solving problems such as topology management,information dissemination,and aggregation.However,previous works sample nodes by their indegrees,without considering the differences in capability among nodes,and result in losing global load balancing.This paper proposes a load balancing gossip protocol for self-organizing overlays-LBTMP (Load-Balancing Topology Management Protocol),which takes into account the differences in capability among nodes and real loads.The novel protocol takes remainder service ability as the determinant for node selection metric,making light loading nodes from local neighbor view as returned samples preferentially.In the meantime,LBTMP selects light loading nodes preferentially for topology information exchange,which can diffuse light loading nodes over the whole overlay more quickly.Simulations show that returned sample node selection is biased to light loading nodes in a global view,and the overlay tends to load balancing.

  15. Science overlay maps: a new tool for research policy and library management

    NARCIS (Netherlands)

    Rafols, I.; Porter, A.L.; Leydesdorff, L.

    2010-01-01

    We present a novel approach to visually locate bodies of research within the sciences, both at each moment of time and dynamically. This article describes how this approach fits with other efforts to locally and globally map scientific outputs. We then show how these science overlay maps help benchm

  16. Interactive overlays: a new method for generating global journal maps from Web-of-Science data

    NARCIS (Netherlands)

    Leydesdorff, L.; Rafols, I.

    2012-01-01

    Recent advances in methods and techniques enable us to develop interactive overlays to a global map of science based on aggregated citation relations among the 9162 journals contained in the Science Citation Index and Social Science Citation Index 2009. We first discuss the pros and cons of the vari

  17. Precision-guided surgical navigation system using laser guidance and 3D autostereoscopic image overlay.

    Science.gov (United States)

    Liao, Hongen; Ishihara, Hirotaka; Tran, Huy Hoang; Masamune, Ken; Sakuma, Ichiro; Dohi, Takeyoshi

    2010-01-01

    This paper describes a precision-guided surgical navigation system for minimally invasive surgery. The system combines a laser guidance technique with a three-dimensional (3D) autostereoscopic image overlay technique. Images of surgical anatomic structures superimposed onto the patient are created by employing an animated imaging method called integral videography (IV), which can display geometrically accurate 3D autostereoscopic images and reproduce motion parallax without the need for special viewing or tracking devices. To improve the placement accuracy of surgical instruments, we integrated an image overlay system with a laser guidance system for alignment of the surgical instrument and better visualization of patient's internal structure. We fabricated a laser guidance device and mounted it on an IV image overlay device. Experimental evaluations showed that the system could guide a linear surgical instrument toward a target with an average error of 2.48 mm and standard deviation of 1.76 mm. Further improvement to the design of the laser guidance device and the patient-image registration procedure of the IV image overlay will make this system practical; its use would increase surgical accuracy and reduce invasiveness.

  18. Assessing the crossdisciplinarity of technology-enhanced learning with science overlay maps and diversity measures

    NARCIS (Netherlands)

    Kalz, Marco; Specht, Marcus

    2013-01-01

    This paper deals with the assessment of the crossdisciplinarity of technology-enhanced learning (TEL). Based on a general discussion of the concept interdisciplinarity and a summary of the discussion in the field two empirical methods from scientometrics are introduced and applied. Science overlay m

  19. High order overlay modeling and APC simulation with Zernike-Legendre polynomials

    Science.gov (United States)

    Ju, JawWuk; Kim, MinGyu; Lee, JuHan; Sherwin, Stuart; Hoo, George; Choi, DongSub; Lee, Dohwa; Jeon, Sanghuck; Lee, Kangsan; Tien, David; Pierson, Bill; Robinson, John C.; Levy, Ady; Smith, Mark D.

    2015-03-01

    Feedback control of overlay errors to the scanner is a well-established technique in semiconductor manufacturing [1]. Typically, overlay errors are measured, and then modeled by least-squares fitting to an overlay model. Overlay models are typically Cartesian polynomial functions of position within the wafer (Xw, Yw), and of position within the field (Xf, Yf). The coefficients from the data fit can then be fed back to the scanner to reduce overlay errors in future wafer exposures, usually via a historically weighted moving average. In this study, rather than using the standard Cartesian formulation, we examine overlay models using Zernike polynomials to represent the wafer-level terms, and Legendre polynomials to represent the field-level terms. Zernike and Legendre polynomials can be selected to have the same fitting capability as standard polynomials (e.g., second order in X and Y, or third order in X and Y). However, Zernike polynomials have the additional property of being orthogonal over the unit disk, which makes them appropriate for the wafer-level model, and Legendre polynomials are orthogonal over the unit square, which makes them appropriate for the field-level model. We show several benefits of Zernike/Legendre-based models in this investigation in an Advanced Process Control (APC) simulation using highly-sampled fab data. First, the orthogonality property leads to less interaction between the terms, which makes the lot-to-lot variation in the fitted coefficients smaller than when standard polynomials are used. Second, the fitting process itself is less coupled - fitting to a lower-order model, and then fitting the residuals to a higher order model gives very similar results as fitting all of the terms at once. This property makes fitting techniques such as dual pass or cascading [2] unnecessary, and greatly simplifies the options available for the model recipe. The Zernike/Legendre basis gives overlay performance (mean plus 3 sigma of the residuals

  20. 16 CFR Appendix to Part 23 - Exemptions Recognized in the Assay for Quality of Gold Alloy, Gold Filled, Gold Overlay, Rolled...

    Science.gov (United States)

    2010-01-01

    ... Quality of Gold Alloy, Gold Filled, Gold Overlay, Rolled Gold Plate, Silver, and Platinum Industry...—Exemptions Recognized in the Assay for Quality of Gold Alloy, Gold Filled, Gold Overlay, Rolled Gold Plate... be considered in any assay for quality of a gold filled, gold overlay and rolled gold plate...

  1. Two Dimensional Array Based Overlay Network for Balancing Load of Peer-to-Peer Live Video Streaming

    Science.gov (United States)

    Faruq Ibn Ibrahimy, Abdullah; Rafiqul, Islam Md; Anwar, Farhat; Ibn Ibrahimy, Muhammad

    2013-12-01

    The live video data is streaming usually in a tree-based overlay network or in a mesh-based overlay network. In case of departure of a peer with additional upload bandwidth, the overlay network becomes very vulnerable to churn. In this paper, a two dimensional array-based overlay network is proposed for streaming the live video stream data. As there is always a peer or a live video streaming server to upload the live video stream data, so the overlay network is very stable and very robust to churn. Peers are placed according to their upload and download bandwidth, which enhances the balance of load and performance. The overlay network utilizes the additional upload bandwidth of peers to minimize chunk delivery delay and to maximize balance of load. The procedure, which is used for distributing the additional upload bandwidth of the peers, distributes the additional upload bandwidth to the heterogeneous strength peers in a fair treat distribution approach and to the homogeneous strength peers in a uniform distribution approach. The proposed overlay network has been simulated by Qualnet from Scalable Network Technologies and results are presented in this paper.

  2. The Research of QoS Mechanisms Based Overlay Network%基于Overlay Network的QoS机制研究

    Institute of Scientific and Technical Information of China (English)

    邱春荣; 王湘渝

    2009-01-01

    重叠网服务质量(OverQoS)是一个崭新的研究课题.该文从应用的角度出发,根据OverQoS的驱动者不同,将基于重叠网的QoS架构分为主机系统驱动型和Overlay ISP驱动型,并剖析了两种OverQoS模型的内在特点,最后提出了相应的技术实现方案.

  3. Holistic overlay control for multi-patterning process layers at the 10nm and 7nm nodes

    Science.gov (United States)

    Verstappen, Leon; Mos, Evert; Wardenier, Peter; Megens, Henry; Schmitt-Weaver, Emil; Bhattacharyya, Kaustuve; Adam, Omer; Grzela, Grzegorz; van Heijst, Joost; Willems, Lotte; Wildenberg, Jochem; Ignatova, Velislava; Chen, Albert; Elich, Frank; Rajasekharan, Bijoy; Vergaij-Huizer, Lydia; Lewis, Brian; Kea, Marc; Mulkens, Jan

    2016-03-01

    Multi-patterning lithography at the 10-nm and 7-nm nodes is driving the allowed overlay error down to extreme low values. Advanced high order overlay correction schemes are needed to control the process variability. Additionally the increase of the number of split layers results in an exponential increase of metrology complexity of the total overlay and alignment tree. At the same time, the process stack includes more hard-mask steps and becomes more and more complex, with as consequence that the setup and verification of the overlay metrology recipe becomes more critical. All of the above require a holistic approach that addresses total overlay optimization from process design to process setup and control in volume manufacturing. In this paper we will present the holistic overlay control flow designed for 10-nm and 7-nm nodes and illustrate the achievable ultimate overlay performance for a logic and DRAM use case. As figure 1 illustrates we will explain the details of the steps in the holistic flow. Overlay accuracy is the driver for target design and metrology tool optimization like wavelength and polarization. We will show that it is essential to include processing effects like etching and CMP which can result in a physical asymmetry of the bottom grating of diffraction based overlay targets. We will introduce a new method to create a reference overlay map, based on metrology data using multiple wavelengths and polarization settings. A similar approach is developed for the wafer alignment step. The overlay fingerprint correction using linear or high order correction per exposure (CPE) has a large amount of parameters. It is critical to balance the metrology noise with the ultimate correction model and the related metrology sampling scheme. Similar approach is needed for the wafer align step. Both for overlay control as well as alignment we have developed methods which include efficient use of metrology time, available for an in the litho-cluster integrated

  4. Co-combustion characteristics and blending optimization of tobacco stem and high-sulfur bituminous coal based on thermogravimetric and mass spectrometry analyses.

    Science.gov (United States)

    Zhang, Kaihua; Zhang, Kai; Cao, Yan; Pan, Wei-ping

    2013-03-01

    Despite much research on co-combustion of tobacco stem and high-sulfur coal, their blending optimization has not been effectively found. This study investigated the combustion profiles of tobacco stem, high-sulfur bituminous coal and their blends by thermogravimetric analysis. Ignition and burnout performances, heat release performances, and gaseous pollutant emissions were also studied by thermogravimetric and mass spectrometry analyses. The results indicated that combustion of tobacco stem was more complicated than that of high-sulfur bituminous coal, mainly shown as fixed carbon in it was divided into two portions with one early burning and the other delay burning. Ignition and burnout performances, heat release performances, and gaseous pollutant emissions of the blends present variable trends with the increase of tobacco stem content. Taking into account the above three factors, a blending ratio of 0–20% tobacco stem content is conservatively proposed as optimum amount for blending.

  5. Advances in Interlaboratory Testing and Evaluation of Bituminous Materials State-of-the-Art Report of the RILEM Technical Committee 206-ATB

    CERN Document Server

    Bahia, Hussain; Canestrari, Francesco; Roche, Chantal; Benedetto, Hervé; Piber, Herald; Sybilski, Dariusz

    2013-01-01

    This STAR on asphalt materials presents the achievements of RILEM TC 206 ATB, acquired over many years of interlaboratory tests and international knowledge exchange. It covers experimental aspects of bituminous binder fatigue testing; the background on compaction methods and imaging techniques for characterizing asphalt mixtures including validation of a new imaging software; it focuses on experimental questions and analysis tools regarding mechanical wheel tracking tests, comparing results from different labs and using finite element techniques. Furthermore, long-term rutting prediction and evaluation for an Austrian road are discussed, followed by an extensive analysis and test program on interlayer bond testing of three different test sections which were specifically constructed for this purpose. Finally, the key issue of manufacturing reclaimed hot mix asphalt in the laboratory is studied and recommendations for laboratory ageing of bituminous mixtures are given.

  6. Response to Comment on "Sphagnum Mosses from 21 Ombrotrophic Bogs in the Athabasca Bituminous Sands Region Show no Significant Atmospheric Contamination of “Heavy Metals”"

    OpenAIRE

    SHOTYK W.; BELLAND Rene; Duke, John; KEMPTER Heike; KRACHLER MICHAEL; NOERNBERG Tommy; Pelletier, Rick; Vile, Melanie; WIEDER Kelman; ZACCONE Claudio; Zhang, Shuangquan

    2015-01-01

    Blais and Donahue (2015) draw attention to many contemporary environmental issues and concerns regarding the industrial development of the Athabasca Bituminous Sands (ABS), most of which are outside of the scope of our original study (Shotyk et al., 2014). Here we restrict our response to the remarks they made which actually apply to our paper. The focus of our paper was the abundance and spatial variation in concentrations of “heavy metals” (selected chalcophile elements namely Ag, Cd, Pb...

  7. Overlay Network技术在云计算数据中心中的应用

    Institute of Scientific and Technical Information of China (English)

    马文杰

    2014-01-01

    随着云计算技术的飞速普及和发展,传统的数据中心逐渐向由各种虚拟化技术所支撑的云数据中心转变.服务器虚拟化、存储虚拟化已被大量运用在数据中心的组建中,新型的云数据中心对组网提出了新的要求.overlay network技术作为一种网络虚拟化技术,为解决云数据中心的组网问题提供技术支持.本文对overlay network技术进行了分析研究,并探讨了其在云数据中心中的应用.

  8. Combined conjunctival autograft and overlay amniotic membrane transplantation; a novel surgical treatment for pterygium.

    Science.gov (United States)

    Ghanavati, Siamak Zarei; Shousha, Mohamed Abou; Betancurt, Carolina; Perez, Victor L

    2014-01-01

    The authors report the long-term results of combined conjunctival autograft and overlay amniotic membrane transplantation (AMT) for treatment of pterygium as a new surgical technique. Nineteen patients including 12 male and 7 female subjects with pterygium (primary, 14 cases; recurrent, 5 cases) underwent combined conjunctival autograft and overlay AMT and were followed from 10 to 26 months. Mean age was 44.21±12.49 (range, 29.0-73.0) years. In one patient with grade T3 primary pterygium, the lesion recurred (5.2%, recurrence rate). No intra-and postoperative complication developed. This procedure seems a safe and effective surgical technique for pterygium treatment. Protection of the ocular surface during the early postoperative period reduces the friction-induced inflammation and might be helpful to prevent the recurrence.

  9. Cast titanium overlay denture for a geriatric patient with a reduced vertical dimension.

    Science.gov (United States)

    Guttal, Satyabodh; Patil, Narendra P

    2005-12-01

    An older patient reporting to the dental surgery for his/her dental treatment is becoming a common occurrence. Improved oral hygiene has meant that teeth are retained for a longer time, along with the potential problems of attrition, decreased vertical dimension, temporomandibular joint discomfort/strain, and poor aesthetics. The case in question is that of a 65-year-old male patient who had severe attrition in the lower arch, temporomandibular joint pain and reduced vertical dimension. The maxillary arch had previously been restored with a fixed partial prosthesis. For restoration of the lower teeth, a removable cast titanium overlay denture was fabricated incorporating an increased vertical dimension. Porcelain facings were placed to restore the aesthetics of the anterior teeth. The titanium was cast in a semi-automatic electric arc, pressure type casting machine. A titanium overlay denture with porcelain facing on the anterior teeth may provide a means of restoring a patient's concerns regarding aesthetics and function.

  10. Application of graph overlay method to environmental impact assessment of railway noise

    Institute of Scientific and Technical Information of China (English)

    WU Xiao-ping; YANG Xiao-yu; MA Chao-qun; RAN Mao-ping

    2005-01-01

    The graph overlay method is used to evaluate the noise impact of route alignment and the results can serve as a reference for the route alignment optimal selection. The geographic information system(GIS), with its powerful function of handling attribute data and spatial analysis, is adopted to calculate the noise comprehensive impact area of each alignment. With the graph overlay method, the noise vulnerability and noise impact distribution are both taken into account in the noise impact assessment of route alignment. With GIS, the efficiency of work and the reliability of result are greatly improved. By a combination of them, the noise impact on environment is fully presented in a visual way and the assessment result has vital value in route alignment optimal selection. A detailed case study is illustrated and the efficiency of the method is verified.

  11. Science overlay maps: a new tool for research policy and library management

    CERN Document Server

    Rafols, Ismael; Leydesdorff, Loet

    2009-01-01

    We present a novel approach to visually locate bodies of research within the sciences, both at each moment of time and dynamically. This article describes how this approach fits with other efforts to locally and globally map scientific outputs. We then show how these science overlay maps help benchmark, explore collaborations, and track temporal changes, using examples of universities, corporations, funding agencies, and research topics. We address conditions of application, with their advantages, downsides and limitations. Overlay maps especially help investigate the increasing number of scientific developments and organisations that do not fit within traditional disciplinary categories. We make these tools accessible to help researchers explore the ongoing socio-cognitive transformation of science and technology systems.

  12. DEAON: dynamically-evolving active overlay networks for scalable information retrieval

    Institute of Scientific and Technical Information of China (English)

    Huang Xinli; Ma Fanyuan

    2007-01-01

    In this paper,we propose the dynamically-evolving active overlay network(DEAON),which is an efficient,scalable yet simple protocol to facilitate applications of decentralized information retrieval in P2P networks.DEAON consists of three novel components:a Desirable Topology Construction and Adantation algorithm to guide the evolution of the overlay topology towards a small-world-like graph;a Semantic-based Neighbor Selection scheme to conduct an online neighbor ranking;a Topology-aware Intelligent Search mechanism to forward incoming queries to deliberately selected neighbors.We deploy and compare DEAON with other several existing distributed search techniques over static and dynamic environments.The results indicate that DEAON outperforms its competitors by achieving higher recall rate while using much less network resources,in both of the above environments.

  13. A TWO-LAYER RECURRENT NEURAL NETWORK BASED APPROACH FOR OVERLAY MULTICAST

    Institute of Scientific and Technical Information of China (English)

    Liu Shidong; Zhang Shunyi; Zhou Jinquan; Qiu Gong'an

    2008-01-01

    Overlay multicast has become one of the most promising multicast solutions for IP network, and Neutral Network(NN) has been a good candidate for searching optimal solutions to the constrained shortest routing path in virtue of its powerful capacity for parallel computation. Though traditional Hopfield NN can tackle the optimization problem, it is incapable of dealing with large scale networks due to the large number of neurons. In this paper, a neural network for overlay multicast tree computation is presented to reliably implement routing algorithm in real time. The neural network is constructed as a two-layer recurrent architecture, which is comprised of Independent Variable Neurons (IDVN) and Dependent Variable Neurons (DVN), according to the independence of the decision variables associated with the edges in directed graph. Compared with the heuristic routing algorithms, it is characterized as shorter computational time, fewer neurons, and better precision.

  14. A Hybrid P2P Overlay Network for Non-strictly Hierarchically Categorized Content

    Science.gov (United States)

    Wan, Yi; Asaka, Takuya; Takahashi, Tatsuro

    In P2P content distribution systems, there are many cases in which the content can be classified into hierarchically organized categories. In this paper, we propose a hybrid overlay network design suitable for such content called Pastry/NSHCC (Pastry for Non-Strictly Hierarchically Categorized Content). The semantic information of classification hierarchies of the content can be utilized regardless of whether they are in a strict tree structure or not. By doing so, the search scope can be restrained to any granularity, and the number of query messages also decreases while maintaining keyword searching availability. Through simulation, we showed that the proposed method provides better performance and lower overhead than unstructured overlays exploiting the same semantic information.

  15. Research on P2P Overlay Network Model with Small-world Features

    Directory of Open Access Journals (Sweden)

    Hao LIU

    2013-09-01

    Full Text Available Topology structure of P2P network decides its system performance. However, the existing P2P network models don’t take clustering and symmetry of nodes into account. Based on the algebra and graph theory method of Cayley graph, this paper proposes a novel P2P overlay network model with small-world features. Its simplicity and symmetry can ensure the self-organization and scalability of P2P network. The results of analysis and experiment shows that this model provides better robustness, higher enquiry efficiency and better load balance than the existing P2P Overlay Network models such as Chord and CAN. Furthermore, it possesses the property of high clustering.

  16. A hierarchical P2P overlay network for interest-based media contents lookup

    Science.gov (United States)

    Lee, HyunRyong; Kim, JongWon

    2006-10-01

    We propose a P2P (peer-to-peer) overlay architecture, called IGN (interest grouping network), for contents lookup in the DHC (digital home community), which aims to provide a formalized home-network-extended construction of current P2P file sharing community. The IGN utilizes the Chord and de Bruijn graph for its hierarchical overlay network construction. By combining two schemes and by inheriting its features, the IGN efficiently supports contents lookup. More specifically, by introducing metadata-based lookup keyword, the IGN offers detailed contents lookup that can reflect the user interests. Moreover, the IGN tries to reflect home network environments of DHC by utilizing HG (home gateway) of each home network as a participating node of the IGN. Through experimental and analysis results, we show that the IGN is more efficient than Chord, a well-known DHT (distributed hash table)-based lookup protocol.

  17. Major, trace, and natural radioactive elements in bituminous coal from Australia, Romania, Russia, South Africa and Ukraine: A comparative study

    Energy Technology Data Exchange (ETDEWEB)

    Duliu, O.G.; Culicov, O.A.; Radulescu, I.; Cristea, C.; Vasiu, T. [University of Bucharest, Bucharest (Romania). Dept. of Atomic & Nuclear Physics

    2005-05-01

    Five samples of bituminous coal collected from different basins (Australia, Romania, Russia, South Africa and Ukraine) have been investigated by using different analytical techniques. Na, Mg, Al, Cl, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Br, Rb, Sr, Mo, Sn, In, Sb, Cs, Ba, La, Ce, Nd, Sm, Eu, Gd, Tb, Dy, Lu, Hf, Ta, W, Hg, Th and U have been determined by neutron activation analysis, K-40, U-238, U-235 and Th-232 have been measured radiometrically, H, C, O, N, and S have been dosed by dynamic flash combustion, while gravimetric methods have been used to measure moisture and ash content together with calorific value. Major mineralogical fractions have been investigated by means of X-ray diffraction. The results have shown significant positive correlations between radiometric and activation analysis results, between calorific value and carbon, nitrogen and hydrogen concentrations and negative significant correlations between calorific value and ash content. According to the Romanian Regulations, only Cr and Ni for Romanian coal exceeded the minimum threshold to be considered unpolluting elements. The distribution of rare earth elements, La to Th ratio, as well as of Sc, La and Th together with Co, Hf and Th have confirmed that, irrespective of sample sources, the mineral part of coal has a composition close to that of the upper continental crust.

  18. Plasma-Augmented Fluidized Bed Gasification of Sub-bituminous Coal in CO2-O2 Atmospheres

    Science.gov (United States)

    Lelievre, C.; Pickles, C. A.; Hultgren, S.

    2016-01-01

    The gasification of a sub-bituminous coal using CO2-O2 gas mixtures was studied in a plasma-augmented fluidized bed gasifier. Firstly, the coal was chemically characterized and the gasification process was examined using Thermogravimetric and Differential Thermal Analysis (TGA/DTA) in CO2, O2 and at a CO2 to O2 ratio of 3 to 1. Secondly, the equilibrium gas compositions were obtained using the Gibbs free energy minimization method (HSC Chemistry®7). Thirdly, gasification tests were performed in a plasma-augmented fluidized bed and the off-gas temperatures and compositions were determined. Finally, for comparison purposes, control tests were conducted using a conventional fluidized bed coal gasifier and these results were compared to those achieved in the plasma-augmented fluidized bed gasifier. The effects of bed temperature and CO2 to O2 ratio were studied. For both gasifiers, at a given bed temperature, the off-gas compositions were in general agreement with the equilibrium values. Also, for both gasifiers, an experimental CO2 to O2 ratio of about 3 to 1 resulted in the highest syngas grade (%CO + %H2). Both higher off-gas temperatures and syngas grades could be achieved in the plasma-augmented gasifier, in comparison to the conventional gasifier. These differences were attributed to the higher bed temperatures in the plasma-augmented fluidized bed gasifier.

  19. Co-combustion of bituminous coal and biomass fuel blends: Thermochemical characterization, potential utilization and environmental advantage.

    Science.gov (United States)

    Zhou, Chuncai; Liu, Guijian; Wang, Xudong; Qi, Cuicui

    2016-10-01

    The thermochemical characteristics and gaseous trace pollutant behaviors during co-combustion medium-to-low ash bituminous coal with typical biomass residues (corn stalk and sawdust) were investigated. Lowering of ignition index, burnout temperature and activation energy in the major combustion stage are observed in the coal/biomass blends. The blending proportion of 20% and 30% are regarded as the optimum blends for corn stalk and sawdust, respectively, in according the limitations of heating value, activation energy, flame stability and base/acid ratio. The reductions of gaseous As, Cd, Cu, Pb, Zn and polycyclic aromatic hydrocarbon (PAHs) were 4.5%, 7.8%, 6.3%, 9.8%, 9.4% and 17.4%, respectively, when co-combustion coal with 20% corn stalk. The elevated capture of trace elements were found in coal/corn stalk blend, while the coal/sawdust blend has the better PAHs control potential. The reduction mechanisms of gaseous trace pollutants were attributed to the fuel property, ash composition and relative residence time during combustion.

  20. Dye-adsorption capacity of bituminous fly ash and its pozzolanic property after used as dye-adsorbent

    Directory of Open Access Journals (Sweden)

    Penpolcharoen, M.

    2004-02-01

    Full Text Available Bituminous fly ash, which is an industrial waste, was used as an adsorbent to remove dyestuff from the textile-dye wastewater. The batch kinetic and isotherm experiments of the synthetic wastewater were firstly conducted to determine the adsorption behavior and optimal conditions for adsorption. The optimal conditions were then applied to the actual textile-dye wastewater. Under the original conditions of fly ash and wastewater, the results indicated that the color could be removed up to 86.65% by 12 g of the fly ash /L of the wastewater within 30 min. Its adsorption was described by the Freundlich isotherm. The dye-adsorbed fly ash was further studied on its pozzolanic property in terms of compressive strength by using it as a partial substitute to Portland cement type I to produce mortar. The result revealed that the highest compressive strength was of the sample containing 10% by weight of the dye-adsorbed fly ash in replacement of cement. It possessed 215 kg/cm2 at 28 days, which is 92.67% of the sample containing 10% by weight of the original fly ash in replacement of cement, or 83.33 of the cement mortar. For the environmental concern, leachabilities of lead (Pb, chromium (Cr, copper (Cu and zinc (Zn from all mortars were also carried out. No leaching of the heavy metals from any samples could be detected. Hence, the dye-adsorbed fly ash can be used as an environmental friendly construction material.

  1. XPS study and physico-chemical properties of nitrogen-enriched microporous activated carbon from high volatile bituminous coal

    Energy Technology Data Exchange (ETDEWEB)

    Robert Pietrzak [Adam Mickiewicz University, Poznan (Poland). Laboratory of Coal Chemistry and Technology

    2009-10-15

    N-enriched microporous active carbons of different physico-chemical parameters have been obtained from high volatile bituminous coal subjected to the processes of ammoxidation, carbonisation and activation in different sequences. Ammoxidation was performed by a mixture of ammonia and air at the ratio 1:3 (flow ratio 250 ml/min:750 ml/min) at 350{sup o}C, at each stage of production i.e. that of precursor, carbonisate and active carbon. Ammoxidation performed at the stage of demineralised coal or carbonisate has been shown to lead to a significant nitrogen enrichment and to have beneficial effect on the porous structure of the carbon during activation, allowing obtaining samples of the surface area of 2600-2800 m{sup 2}/g and pore volume 1.29-1.60 cm{sup 3}/g to be obtained with the yield of about 50%. The amount of nitrogen introduced into the carbon structure was found to depend on the sequence of the processes applied. The greatest amount of nitrogen was introduced for the processes in the sequence carbonisation {yields} activation {yields} ammoxidation. The introduction of nitrogen at the stage of active carbon leads to a reduction in the surface area and lowering of its sorption capacity. From the XPS study, ammoxidation introduces nitrogen mainly in the form of imines, amines, amides, N-5 and N-6, irrespective of the processing stage at which it is applied. 40 refs., 2 figs., 5 tabs.

  2. Assessment of underground coal gasification in bituminous coals: potential UCG products and markets. Final report, Phase I

    Energy Technology Data Exchange (ETDEWEB)

    None

    1982-01-31

    The following conclusions were drawn from the study: (1) The US will continue to require new sources of energy fuels and substitutes for petrochemical feedstocks into the foreseeable future. Most of this requirement will be met using coal. However, the cost of mining, transporting, cleaning, and preparing coal, disposing of ash or slag and scrubbing stack gases continues to rise; particularly, in the Eastern US where the need is greatest. UCG avoids these pitfalls and, as such, should be considered a viable alternative to the mining of deeper coals. (2) Of the two possible product gases LBG and MBG, MBG is the most versatile. (3) The most logical use for UCG product in the Eastern US is to generate power on-site using a combined-cycle or co-generation system. Either low or medium Btu gas (LBG or MBG) can be used. (4) UCG should be an option whenever surface gasification is considered; particularly, in areas where deeper, higher sulfur coal is located. (5) There are environmental and social benefits to use of UCG over surface gasification in the Eastern US. (6) A site could be chosen almost anywhere in the Illinois and Ohio area where amenable UCG coal has been determined due to the existence of existing transportation or transmission systems. (7) The technology needs to be demonstrated and the potential economic viability determined at a site in the East-North-Central US which has commercial quantities of amenable bituminous coal before utilities will show significant interest.

  3. Monoplane 3D Overlay Roadmap versus Conventional Biplane 2D Roadmap Technique for Neurointervenional Procedures

    Science.gov (United States)

    Jang, Dong-Kyu; Stidd, David A.; Schafer, Sebastian; Chen, Michael; Moftakhar, Roham

    2016-01-01

    Purpose We investigated whether a 3D overlay roadmap using monoplane fluoroscopy offers advantages over a conventional 2D roadmap using biplane fluoroscopy during endovascular aneurysm treatment. Materials and Methods A retrospective chart review was conducted for 131 consecutive cerebral aneurysm embolizations by three neurointerventionalists at a single institution. Allowing for a transition period, the periods from January 2012 to August 2012 (Time Period 1) and February 2013 to July 2013 (Time Period 2) were analyzed for radiation exposure, contrast administration, fluoroscopy time, procedure time, angiographic results, and perioperative complications. Two neurointerventionalists (Group 1) used a conventional 2D roadmap for both Time Periods, and one neurointerventionalist (Group 2) transitioned from a 2D roadmap during Time Period 1 to a 3D overlay roadmap during Time Period 2. Results During Time Period 2, Group 2 demonstrated reduced fluoroscopy time (p<0.001), procedure time (P=0.023), total radiation dose (p=0.001), and fluoroscopy dose (P=0.017) relative to Group 1. During Time Period 2, there was no difference of immediate angiographic results and procedure complications between the two groups. Through the transition from Time Period 1 to Time Period 2, Group 2 demonstrated decreased fluoroscopy time (p< 0.001), procedure time (p=0.022), and procedure complication rate (p=0.041) in Time Period 2 relative to Time Period 1. Conclusion The monoplane 3D overlay roadmap technique reduced fluoroscopy dose and fluoroscopy time during neurointervention of cerebral aneurysms with similar angiographic occlusions and complications rate relative to biplane 2D roadmap, which implies possible compensation of limitations of monoplane fluoroscopy by 3D overlay technique. PMID:27621947

  4. Novel indazole non-nucleoside reverse transcriptase inhibitors using molecular hybridization based on crystallographic overlays.

    Science.gov (United States)

    Jones, Lyn H; Allan, Gill; Barba, Oscar; Burt, Catherine; Corbau, Romuald; Dupont, Thomas; Knöchel, Thorsten; Irving, Steve; Middleton, Donald S; Mowbray, Charles E; Perros, Manos; Ringrose, Heather; Swain, Nigel A; Webster, Robert; Westby, Mike; Phillips, Chris

    2009-02-26

    A major problem associated with non-nucleoside reverse transcriptase inhibitors (NNRTIs) for the treatment of HIV is their lack of resilience to mutations in the reverse transcriptase (RT) enzyme. Using structural overlays of the known inhibitors efavirenz and capravirine complexed in RT as a starting point, and structure-based drug design techniques, we have created a novel series of indazole NNRTIs that possess excellent metabolic stability and mutant resilience.

  5. DSP overlay program design%DSP覆盖(Overlay)程序设计

    Institute of Scientific and Technical Information of China (English)

    吴洁; 李尚柏

    2014-01-01

    The fundamental of the overlay program design technology is to divide the task to several function modules through the modularized designing idea. The memory just need to load the module which would be executed currently, and do not load the others . When the other modules need to be executed, the modules in memory would be unloaded firstly, and then the modules need to execute would be load to memory. As far as the usage condition of memory to be concerned, overlay technology and dynamic link libraries(DLL) is highly similar. With the target platform of TM320C6000 series DSP, this article provide the ways and implementation steps for DSP overlay program design technology through a concrete instance, and discuss every link of the overlay program design technology in detail.%Overlay程序设计技术的基本原理是利用模块化设计思想,将任务划分成多个功能模块,在内存中只加载当前需要执行的模块,不加载其他暂不执行的模块。但当其他模块需要执行时,首先将内存中的模块卸载,然后将需要执行的模块再加载到内存。就内存的使用情况而言,Overlay技术与动态链接库是非常类似的。本文以TM320C6000系列DSP为目标平台,通过一个具体实例给出开发DSP覆盖(Overlay)程序设计技术的方法和实现步骤,详细地讨论了Overlay程序设计技术各个环节。

  6. Nasal bone grafts from the removed hump used as overlay grafts to camouflage concave lateral crura.

    Science.gov (United States)

    Kubilay, Utku; Erdogdu, Suleyman; Sezen, Ozan Seymen

    2014-01-01

    Alar cartilage consists of a medial crus, middle crus and lateral crus. The lateral crus is an important aesthetic and functional structure of the nose. A 32-year-old male patient with concave lateral crura was operated by the authors. An open rhinoplasty with a dorsal approach to the septum is preferred. The nasal bones harvested from the hump, which is an autogenous graft trimmed and sutured on both concave lateral crura as an overlay camouflage grafts. Satisfactory result was achieved.

  7. The Corrosion and Corrosion Fatigue Behavior of Nickel Based Alloy Weld Overlay and Coextruded Claddings

    Science.gov (United States)

    Stockdale, Andrew

    The use of low NOx boilers in coal fired power plants has resulted in sulfidizing corrosive conditions within the boilers and a reduction in the service lifetime of the waterwall tubes. As a solution to this problem, Ni-based weld overlays are used to provide the necessary corrosion resistance however; they are susceptible to corrosion fatigue. There are several metallurgical factors which give rise to corrosion fatigue that are associated with the localized melting and solidification of the weld overlay process. Coextruded coatings offer the potential for improved corrosion fatigue resistance since coextrusion is a solid state coating process. The corrosion and corrosion fatigue behavior of alloy 622 weld overlays and coextruded claddings was investigated using a Gleeble thermo-mechanical simulator retrofitted with a retort. The experiments were conducted at a constant temperature of 600°C using a simulated combustion gas of N2-10%CO-5%CO2-0.12%H 2S. An alternating stress profile was used with a minimum tensile stress of 0 MPa and a maximum tensile stress of 300 MPa (ten minute fatigue cycles). The results have demonstrated that the Gleeble can be used to successfully simulate the known corrosion fatigue cracking mechanism of Ni-based weld overlays in service. Multilayer corrosion scales developed on each of the claddings that consisted of inner and outer corrosion layers. The scales formed by the outward diffusion of cations and the inward diffusion of sulfur and oxygen anions. The corrosion fatigue behavior was influenced by the surface finish and the crack interactions. The initiation of a large number of corrosion fatigue cracks was not necessarily detrimental to the corrosion fatigue resistance. Finally, the as-received coextruded cladding exhibited the best corrosion fatigue resistance.

  8. Microeconomics-based resource allocation in overlay networks by using non-strategic behavior modeling

    Science.gov (United States)

    Analoui, Morteza; Rezvani, Mohammad Hossein

    2011-01-01

    Behavior modeling has recently been investigated for designing self-organizing mechanisms in the context of communication networks in order to exploit the natural selfishness of the users with the goal of maximizing the overall utility. In strategic behavior modeling, the users of the network are assumed to be game players who seek to maximize their utility with taking into account the decisions that the other players might make. The essential difference between the aforementioned researches and this work is that it incorporates the non-strategic decisions in order to design the mechanism for the overlay network. In this solution concept, the decisions that a peer might make does not affect the actions of the other peers at all. The theory of consumer-firm developed in microeconomics is a model of the non-strategic behavior that we have adopted in our research. Based on it, we have presented distributed algorithms for peers' "joining" and "leaving" operations. We have modeled the overlay network as a competitive economy in which the content provided by an origin server can be viewed as commodity and the origin server and the peers who multicast the content to their downside are considered as the firms. On the other hand, due to the dual role of the peers in the overlay network, they can be considered as the consumers as well. On joining to the overlay economy, each peer is provided with an income and tries to get hold of the service regardless to the behavior of the other peers. We have designed the scalable algorithms in such a way that the existence of equilibrium price (known as Walrasian equilibrium price) is guaranteed.

  9. RESTORING A DAMAGED 16-YEAR -OLD INSULATING POLYMER CONCRETE DIKE OVERLAY: REPAIR MATERIALS AND TECHNOLOGIES.

    Energy Technology Data Exchange (ETDEWEB)

    SUGAMA,T.

    2007-01-01

    The objective of this program was to design and formulate organic polymer-based material systems suitable for repairing and restoring the overlay panels of insulating lightweight polymer concrete (ILPC) from the concrete floor and slope wall of a dike at KeySpan liquefied natural gas (LNG) facility in Greenpoint, Brooklyn, NY, just over sixteen years ago. It also included undertaking a small-scale field demonstration to ensure that the commercial repairing technologies were applicable to the designed and formulated materials.

  10. In-die photomask registration and overlay metrology with PROVE using 2D correlation methods

    Science.gov (United States)

    Seidel, D.; Arnz, M.; Beyer, D.

    2011-11-01

    According to the ITRS roadmap, semiconductor industry drives the 193nm lithography to its limits, using techniques like double exposure, double patterning, mask-source optimization and inverse lithography. For photomask metrology this translates to full in-die measurement capability for registration and critical dimension together with challenging specifications for repeatability and accuracy. Especially, overlay becomes more and more critical and must be ensured on every die. For this, Carl Zeiss SMS has developed the next generation photomask registration and overlay metrology tool PROVE® which serves the 32nm node and below and which is already well established in the market. PROVE® features highly stable hardware components for the stage and environmental control. To ensure in-die measurement capability, sophisticated image analysis methods based on 2D correlations have been developed. In this paper we demonstrate the in-die capability of PROVE® and present corresponding measurement results for shortterm and long-term measurements as well as the attainable accuracy for feature sizes down to 85nm using different illumination modes and mask types. Standard measurement methods based on threshold criteria are compared with the new 2D correlation methods to demonstrate the performance gain of the latter. In addition, mask-to-mask overlay results of typical box-in-frame structures down to 200nm feature size are presented. It is shown, that from overlay measurements a reproducibility budget can be derived that takes into account stage, image analysis and global effects like mask loading and environmental control. The parts of the budget are quantified from measurement results to identify critical error contributions and to focus on the corresponding improvement strategies.

  11. A Prediction System Using a P2P Overlay Network for a Bus Arrival System

    Directory of Open Access Journals (Sweden)

    Ssu-Hsuan Lu

    2014-01-01

    Full Text Available Along with the evolution of times and the surge of metropolitan populations, government agencies often promote the construction of public transport. Unlike rail transportation or rapid transit systems, it is often difficult to estimate the vehicle arrival times at each station in a bus transportation system due to metropolitan transportation congestion. Traffic status is often monitored using wireless sensor networks (WSNs. However, WSNs are always separated from one another spatially. Recent studies have considered the connection of multiple sensor networks. This study considers a combination view of peer-to-peer (P2P overlay networks and WSN architecture to predict bus arrival times. Each bus station, which is also a P2P overlay peer, is connected in a P2P overlay network. A sensor installed in each bus can receive data via peers to obtain the moving speed of a bus. Then, each peer can exchange its data to predict bus arrival times at bus stations. This method can considerably increase the accuracy with which bus arrival times can be predicted and can provide traffic status with high precision. Furthermore, these data can also be used to plan new bus routes according to the information gathered.

  12. Managing Peer to Peer and Overlay Content Traffic in ISP Networks

    Directory of Open Access Journals (Sweden)

    Stanislaus Kaosoluchukwu Ogbuokebe

    2013-04-01

    Full Text Available Peer-to-Peer content distribution systems are major source of traffic in today’s internet services, Peer-to-peer (P2P traffic consumes network resources without creating additional revenue. It is estimated that high percentage of broadband bandwidth is consumed by downloads of music, games, video, and other content. The use of peer to peer systems introduces many new problems related to traffic engineering or network optimization. This research work will investigate characteristics and behavioural interactions between Peer to Peer overlay content distribution operations, as well as suggests/discuss algorithms for optimizing P2P content distribution overlay infrastructure and the internet service provider “ISP” network. Techniques to harmonise the relationship between P2P overlay content distribution services and the underlying network is also discussed. Indeed the system performance of a P2P network is critically affected by its overload, thus the processing load of the peers, the communication load and the system management load, must be carefully handled to obtain satisfactory system performance.

  13. Image overlay solution based on threshold detection for a compact near infrared fluorescence goggle system.

    Science.gov (United States)

    Gao, Shengkui; Mondal, Suman B; Zhu, Nan; Liang, RongGuang; Achilefu, Samuel; Gruev, Viktor

    2015-01-01

    Near infrared (NIR) fluorescence imaging has shown great potential for various clinical procedures, including intraoperative image guidance. However, existing NIR fluorescence imaging systems either have a large footprint or are handheld, which limits their usage in intraoperative applications. We present a compact NIR fluorescence imaging system (NFIS) with an image overlay solution based on threshold detection, which can be easily integrated with a goggle display system for intraoperative guidance. The proposed NFIS achieves compactness, light weight, hands-free operation, high-precision superimposition, and a real-time frame rate. In addition, the miniature and ultra-lightweight light-emitting diode tracking pod is easy to incorporate with NIR fluorescence imaging. Based on experimental evaluation, the proposed NFIS solution has a lower detection limit of 25 nM of indocyanine green at 27 fps and realizes a highly precise image overlay of NIR and visible images of mice in vivo. The overlay error is limited within a 2-mm scale at a 65-cm working distance, which is highly reliable for clinical study and surgical use.

  14. Iron aluminide weld overlay coatings for boiler tube protection in coal-fired low NOx boilers

    Energy Technology Data Exchange (ETDEWEB)

    Banovic, S.W.; DuPont, J.N.; Marder, A.R. [Lehigh Univ., Bethlehem, PA (United States). Energy Research Center

    1997-12-01

    Iron aluminide weld overlay coatings are currently being considered for enhanced sulfidation resistance in coal-fired low NO{sub x} boilers. The use of these materials is currently limited due to hydrogen cracking susceptibility, which generally increases with an increase in aluminum concentration of the deposit. The overall objective of this program is to attain an optimum aluminum content with good weldability and improved sulfidation resistance with respect to conventional materials presently in use. Research has been initiated using Gas Tungsten Arc Welding (GTAW) in order to achieve this end. Under different sets of GTAW parameters (wire feed speed, current), both single and multiple pass overlays were produced. Characterization of all weldments was conducted using light optical microscopy, scanning electron microscopy, and electron probe microanalysis. Resultant deposits exhibited a wide range of aluminum contents (5--43 wt%). It was found that the GTAW overlays with aluminum contents above {approximately}10 wt% resulted in cracked coatings. Preliminary corrosion experiments of 5 to 10 wt% Al cast alloys in relatively simple H{sub 2}/H{sub 2}S gas mixtures exhibited corrosion rates lower than 304 stainless steel.

  15. Energy Efficiency in MIMO Underlay and Overlay Device-to-Device Communications and Cognitive Radio Systems

    Science.gov (United States)

    Zappone, Alessio; Matthiesen, Bho; Jorswieck, Eduard Axel

    2017-02-01

    This paper addresses the problem of resource allocation for systems in which a primary and a secondary link share the available spectrum by an underlay or overlay approach. After observing that such a scenario models both cognitive radio and D2D communications, we formulate the problem as the maximization of the secondary energy efficiency subject to a minimum rate requirement for the primary user. This leads to challenging non-convex, fractional problems. In the underlay scenario, we obtain the global solution by means of a suitable reformulation. In the overlay scenario, two algorithms are proposed. The first one yields a resource allocation fulfilling the first-order optimality conditions of the resource allocation problem, by solving a sequence of easier fractional problems. The second one enjoys a weaker optimality claim, but an even lower computational complexity. Numerical results demonstrate the merits of the proposed algorithms both in terms of energy-efficient performance and complexity, also showing that the two proposed algorithms for the overlay scenario perform very similarly, despite the different complexity.

  16. Disbond detection with piezoelectric wafer active sensors in RC structures strengthened with FRP composite overlays

    Institute of Scientific and Technical Information of China (English)

    Victor Giurgiutiu; Kent Harries; Michael Petrou; Joel Bost; Josh B. Quattlebaum

    2003-01-01

    The capability of embedded piezoelectric wafer active sensors (PWAS) to perform in-situ nondestructive evaluation (NDE) for structural health monitoring (SHM) of reinforced concrete (RC) structures strengthened with fiber reinforced polymer (FRP) composite overlays is explored. First, the disbond detection method were developed on coupon specimens consisting of concrete blocks covered with an FRP composite layer. It was found that the prescnce of a disbond crack drastically changes the electromecbanical (E/M) impedance spectrum measured at the PWAS terminals. The spectral changes depend on the distance between the PWAS and the crack tip. Second, large scale experiments were conducted on a RC beam strengthened with carbon fiber reinforced polymer (CFRP) composite overlay. The beam was subject to an acccleratcd fatigue load regime in a three-point bending configuration up to a total of807,415 cycles. During these fatigue tests, the CFRP overlay experienced disbonding beginning at about 500,000 cycles. The PWAS were able to detect the disbonding before it could be reliably seen by visual inspection. Good correlation between the PWAS readings and the position and extent of disbond damage was observed. These preliminary results demonstrate the potential of PWAS technology for SHM of RC structures strengthened with FRP composite ovcrlays.

  17. Numerical evaluation of weld overlay applied to a pressurized water reactor nozzle mock-up

    Energy Technology Data Exchange (ETDEWEB)

    Rabello, Emerson G.; Silva, Luiz L.; Gomes, Paulo T.V., E-mail: egr@cdtn.b, E-mail: silvall@cdtn.b, E-mail: gomespt@cdtn.b [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil). Servico de Integridade Estrutural

    2011-07-01

    The primary water stress corrosion cracking (PWSCC) is a major mechanism of failure in the primary circuit of PWR type nuclear power plants. The PWSCC is associated with the presence of corrosive environment, the susceptibility to corrosion cracking of the materials involved and the tensile stresses presence. Residual stresses generated during dissimilar materials welding can contribute to PWSCC. An alternative to the PWSCC mitigation is the application of external weld layers in the regions of greatest susceptibility to corrosion cracking. This process, called Weld Overlay (WOL), has been widely used in regions of dissimilar weld (low alloy steel and stainless steel with nickel alloy addition) of nozzles and pipes on the primary circuit in order to promote internal compressive stresses on the wall of these components. This paper presents the steps required to the numerical stress evaluation (by finite element method) during the dissimilar materials welding as well as application of Weld Overlay process in a nozzle mock-up. Thus, one can evaluate the effectiveness of the application of weld overlay process to internal compressive stress generation on the wall nozzle. (author)

  18. Structural evolution of the Pb/Si(111) interface with metal overlayer thickness

    Science.gov (United States)

    Souto-Casares, Jaime; Chan, Tzu-Liang; Chelikowsky, James R.; Ho, Kai-Ming; Wang, Cai-Zhuang; Zhang, S. B.

    2015-09-01

    We employ a real-space pseudopotential method to compute the structural energies of a prototypical metal-semiconductor interface. Specifically, we examine a Pb(111) film overlaid on a Si(111) substrate as a function of the metal thickness. For each layer of Pb, we fully relax the atomic coordinates and determine the lowest-energy structure. Owing to the lattice mismatch between the Pb and Si crystal structures, we consider a large supercell containing up to 1505 atoms for the largest system. Systems of this size remain challenging for most current computational approaches and require algorithms specifically designed for highly parallel computational platforms. We examine the structural properties of the interface with respect to the thickness of the metal overlayer, e.g., the corrugation of the profile of the Pb overlayer. The combined influence of the Si substrate and quantum confinement results in a rich profile for a transition between a thin overlayer (less than a few monolayers), where the corrugation is strong, and the bulk region (more than a half-dozen layers), where the overlaid Pb film is atomically flat. This work proves the feasibility of handling systems with such a level of complexity.

  19. Three-dimensional magnetic resonance imaging overlay to assist with percutaneous transhepatic access at the time of cardiac catheterization

    Directory of Open Access Journals (Sweden)

    Wendy Whiteside

    2015-01-01

    Full Text Available Multimodality image overlay is increasingly used for complex interventional procedures in the cardiac catheterization lab. We report a case in which three-dimensional magnetic resonance imaging (3D MRI overlay onto live fluoroscopic imaging was utilized to safely obtain transhepatic access in a 12-year-old patient with prune belly syndrome, complex and distorted abdominal anatomy, and a vascular mass within the liver.

  20. Three-dimensional magnetic resonance imaging overlay to assist with percutaneous transhepatic access at the time of cardiac catheterization.

    Science.gov (United States)

    Whiteside, Wendy; Christensen, Jason; Zampi, Jeffrey D

    2015-01-01

    Multimodality image overlay is increasingly used for complex interventional procedures in the cardiac catheterization lab. We report a case in which three-dimensional magnetic resonance imaging (3D MRI) overlay onto live fluoroscopic imaging was utilized to safely obtain transhepatic access in a 12-year-old patient with prune belly syndrome, complex and distorted abdominal anatomy, and a vascular mass within the liver.

  1. Two-layer critical dimensions and overlay process window characterization and improvement in full-chip computational lithography

    Science.gov (United States)

    Sturtevant, John L.; Liubich, Vlad; Gupta, Rachit

    2016-04-01

    Edge placement error (EPE) was a term initially introduced to describe the difference between predicted pattern contour edge and the design target for a single design layer. Strictly speaking, this quantity is not directly measurable in the fab. What is of vital importance is the relative edge placement errors between different design layers, and in the era of multipatterning, the different constituent mask sublayers for a single design layer. The critical dimensions (CD) and overlay between two layers can be measured in the fab, and there has always been a strong emphasis on control of overlay between design layers. The progress in this realm has been remarkable, accelerated in part at least by the proliferation of multipatterning, which reduces the available overlay budget by introducing a coupling of overlay and CD errors for the target layer. Computational lithography makes possible the full-chip assessment of two-layer edge to edge distances and two-layer contact overlap area. We will investigate examples of via-metal model-based analysis of CD and overlay errors. We will investigate both single patterning and double patterning. For single patterning, we show the advantage of contour-to-contour simulation over contour to target simulation, and how the addition of aberrations in the optical models can provide a more realistic CD-overlay process window (PW) for edge placement errors. For double patterning, the interaction of 4-layer CD and overlay errors is very complex, but we illustrate that not only can full-chip verification identify potential two-layer hotspots, the optical proximity correction engine can act to mitigate such hotspots and enlarge the joint CD-overlay PW.

  2. Brief Announcement: Decentralized Construction of Multicast Trees Embedded into P2P Overlay Networks based on Virtual Geometric Coordinates

    CERN Document Server

    Andreica, Mugurel Ionut; Sambotin, Ana-Delia; Tapus, Nicolae; 10.1145/1835698.1835766

    2010-01-01

    In this paper we consider the problem of efficiently constructing in a fully distributed manner multicast trees which are embedded into P2P overlays using virtual geometric node coordinates. We consider two objectives: to minimize the number of messages required for constructing a multicast tree by using the geometric properties of the P2P overlay, and to construct stable multicast trees when the lifetime durations of the peers are known.

  3. Advanced overlay: sampling and modeling for optimized run-to-run control

    Science.gov (United States)

    Subramany, Lokesh; Chung, WoongJae; Samudrala, Pavan; Gao, Haiyong; Aung, Nyan; Gomez, Juan Manuel; Gutjahr, Karsten; Park, DongSuk; Snow, Patrick; Garcia-Medina, Miguel; Yap, Lipkong; Demirer, Onur Nihat; Pierson, Bill; Robinson, John C.

    2016-03-01

    In recent years overlay (OVL) control schemes have become more complicated in order to meet the ever shrinking margins of advanced technology nodes. As a result, this brings up new challenges to be addressed for effective run-to- run OVL control. This work addresses two of these challenges by new advanced analysis techniques: (1) sampling optimization for run-to-run control and (2) bias-variance tradeoff in modeling. The first challenge in a high order OVL control strategy is to optimize the number of measurements and the locations on the wafer, so that the "sample plan" of measurements provides high quality information about the OVL signature on the wafer with acceptable metrology throughput. We solve this tradeoff between accuracy and throughput by using a smart sampling scheme which utilizes various design-based and data-based metrics to increase model accuracy and reduce model uncertainty while avoiding wafer to wafer and within wafer measurement noise caused by metrology, scanner or process. This sort of sampling scheme, combined with an advanced field by field extrapolated modeling algorithm helps to maximize model stability and minimize on product overlay (OPO). Second, the use of higher order overlay models means more degrees of freedom, which enables increased capability to correct for complicated overlay signatures, but also increases sensitivity to process or metrology induced noise. This is also known as the bias-variance trade-off. A high order model that minimizes the bias between the modeled and raw overlay signature on a single wafer will also have a higher variation from wafer to wafer or lot to lot, that is unless an advanced modeling approach is used. In this paper, we characterize the bias-variance trade off to find the optimal scheme. The sampling and modeling solutions proposed in this study are validated by advanced process control (APC) simulations to estimate run-to-run performance, lot-to-lot and wafer-to- wafer model term monitoring to

  4. Corrosion resistance and microstructure of alloy 625 weld overlay on ASTM A516 grade 70

    Energy Technology Data Exchange (ETDEWEB)

    Moradi, Mohammad J. [Amirkabir Univ. of Technology, Tehran (Iran, Islamic Republic of). Petroleum Engineering Dept.; Ketabchi, Mostafa [Amirkabir Univ. of Technology, Tehran (Iran, Islamic Republic of). Mining and Metallurgical Engineering Dept.

    2016-02-01

    Nickel-based alloys are a crucial class of materials because of their excellent corrosion resistance. In the present study, single layer and two layers alloy 625 weld overlays were deposited by GTAW process on A516 grade 70 carbon steel. The dilution in terms of Fe, Ni, Mo and Nb content was calculated in 30 points of weld overlay. Microstructure observations showed that alloy 625 had austenitic structure with two types of Laves and NbC secondary phases. The uniform and pitting corrosion resistance of alloy 625 weld overlay as casted and as forged were evaluated in accordance with ASTM G48-2011 standard at different temperatures to determine the weight loss and critical pitting temperature. For achieving a better comparison, samples from alloy 625 as casted and as forged were tested under the same conditions. The results point out that single layer alloy 625 weld overlay is not suitable for chloride containing environments, two layers alloy 625 weld overlay and alloy 625 as casted have acceptable corrosion resistance and almost the same critical pitting temperature. Alloy 625 as forged has the best corrosion resistance and the highest critical pitting temperature among all test specimens. Also, the corrosion behavior was evaluated in accordance with ASTM G28 standard. The corrosion rate of single layer weld overlay was unacceptable. The average corrosion rate of two layers weld overlay and in casted condition were 35.82 and 33.01 mpy, respectively. [German] Nickellegierungen sind aufgrund ihres exzellenten Korrosionswiderstandes eine bedeutende Werkstoffklasse. In der diesem Beitrag zugrunde liegenden Studie wurden mittels WIG-Schweissens ein- und zweilagige Schweissplattierungen auf den Kohlenstoffstahl A516 (Grade 70) aufgebracht. Die Vermischung in Form des Fe-, Ni-, Mo- und Nb-Gehaltes wurde an 30 Punkten der Schweissplattierungen berechnet. Die mikrostrukturellen Untersuchungen ergaben, dass die Legierung 625 eine austenitische Struktur mit zwei Arten von

  5. Effect of asphaltene and resin oils on the viscosity of bituminous petroleum materials to be used as asphalt primers

    Directory of Open Access Journals (Sweden)

    Bencomo, M. R.

    2006-03-01

    Full Text Available The bituminous crude from the Machete, Venezuela, area, which has such a fluid consistency that it falls outside the normal scope of the A5TM D-5 (1 penetration test exceeding the 3D-mm ceiling specified in that standard and can be used as an asphalt primer: Like other asphalt products, these materials are -chemically speaking- a mix of numerous naphthenic, paraffinic and aromatic hydrocarbons and heterocyclic compounds containing sulphur, nitrogen, oxygen and so on. They have a dense and a malthene oil phase which, along with the natural hydrocarbons additives used in these products acts as a volatile fluidizer. The former is described as a mix of asphaltenes: complex high molecular weight substances that are insoluble in paraffinic hydrocarbons and soluble in aromatic compounds such as benzene. The malthene oil phase, in turn, consists in a mix of resins and hydrocarbons and together the two constitute a colloidal system. The experiments discussed in the present paper were conducted to determine the effect of the proportion of asphaltenes and resin oils on the viscosity of such bituminous crude emulsions/ with a view to their use as primers. These experiments were run in a Parr batch reactor in a nitrogen atmosphere using n-heptane as a solvent. The resins were separated after the asphaltenes precipitated from the samples and subsequently from the malthene fraction obtained. The results showed that the asphaltenes account for the structural characteristics and consistency of the medium and the resin oils for its cohesive properties/,the malthene oils act as solvents.Los crudos extrapesados procedentes del área Machete (Venezuela son materiales de consistencia blanda o fluida, por lo que se salen del campo en el que normalmente se aplica el ensayo de penetración a productos asfálticos según el método ASTM D-5 (1, cuyo límite máximo es 30 mm, y pueden ser utilizados como pinturas asfálticas de imprimación. Al igual que otros productos

  6. Influence of an igneous intrusion on the inorganic geochemistry of a bituminous coal from Pitkin County, Colorado

    Science.gov (United States)

    Finkelman, R.B.; Bostick, N.H.; Dulong, F.T.; Senftle, F.E.; Thorpe, A.N.

    1998-01-01

    Although the effects of igneous dikes on the organic matter in coal have been observed at many localities there is virtually no information on the effects of the intrusions of the inorganic constituents in the coal. Such a study may help to elucidate the behavior of trace elements during in situ gasification of coal and may provide insights into the resources potential for coal and coke affected by the intrusion. To determine the effects of an igneous intrusion on the inorganic chemistry of a coal we used a series of 11 samples of coal and natural coke that had been collected at intervals from 3 to 106 cm from a dike that intruded the bituminous Dutch Creek coal in Pitkin, CO. The samples were chemically analyzed for 66 elements. SEM-EDX and X-ray diffraction analysis were performed on selected samples. Volatile elements such as F, Cl, Hg, and Se are not depleted in the samples (coke and coal) nearest the dike that were exposed to the highest temperatures. Their presence in these samples is likely due to secondary enrichment following volatilization of the elements inherent in the coal. Equilibration with ground water may account for the uniform distribution of Na, B, and Cl. High concentrations of Ca, Mg, Fe, Mn, Sr, and CO2 in the coke region are attributed to the reaction of CO and CO2 generated during the coking of the coal with fluids from the intrusion, resulting in the precipitation of carbonates. Similarly, precipitation of sulfide minerals in the coke zone may account for the relatively high concentrations of Ag, Hg, Cu, Zn, and Fe. Most elements are concentrated at the juncture of the fluidized coke and the thermally metamorphosed coal. Many of the elements enriched in this region (for example, Ga, Ge, Mo, Rb, U, La, Ce, Al, K, and Si) may have been adsorbed on either the clays or the organic matter or on both.Although the effects of igneous dikes on the organic matter in coal have been observed at many localities there is virtually no information on the

  7. Adaptive on-line estimation and control of overlay tool bias

    Science.gov (United States)

    Martinez, Victor M.; Finn, Karen; Edgar, Thomas F.

    2003-06-01

    Modern lithographic manufacturing processes rely on various types of exposure tools, used in a mix-and-match fashion. The motivation to use older tools alongside state-of-the-art tools is lower cost and one of the tradeoffs is a degradation in overlay performance. While average prices of semiconductor products continue to fall, the cost of manufacturing equipment rises with every product generation. Lithography processing, including the cost of ownership for tools, accounts for roughly 30% of the wafer processing costs, thus the importance of mix-and-match strategies. Exponentially Weighted Moving Average (EWMA) run-by-run controllers are widely used in the semiconductor manufacturing industry. This type of controller has been implemented successfully in volume manufacturing, improving Cpk values dramatically in processes like photolithography and chemical mechanical planarization. This simple, but powerful control scheme is well suited for adding corrections to compensate for Overlay Tool Bias (OTB). We have developed an adaptive estimation technique to compensate for overlay variability due to differences in the processing tools. The OTB can be dynamically calculated for each tool, based on the most recent measurements available, and used to correct the control variables. One approach to tracking the effect of different tools is adaptive modeling and control. The basic premise of an adaptive system is to change or adapt the controller as the operating conditions of the system change. Using closed-loop data, the adaptive control algorithm estimates the controller parameters using a recursive estimation technique. Once an updated model of the system is available, modelbased control becomes feasible. In the simplest scenario, the control law can be reformulated to include the current state of the tool (or its estimate) to compensate dynamically for OTB. We have performed simulation studies to predict the impact of deploying this strategy in production. The results

  8. Passivating surface states on water splitting hematite photoanodes with alumina overlayers

    KAUST Repository

    Le Formal, Florian

    2011-01-24

    Hematite is a promising material for inexpensive solar energy conversion via water splitting but has been limited by the large overpotential (0.5-0.6 V) that must be applied to afford high water oxidation photocurrent. This has conventionally been addressed by coating it with a catalyst to increase the kinetics of the oxygen evolution reaction. However, surface recombination at trapping states is also thought to be an important factor for the overpotential, and herein we investigate a strategy to passivate trapping states using conformal overlayers applied by atomic layer deposition. While TiO2 overlayers show no beneficial effect, we find that an ultra-thin coating of Al2O3 reduces the overpotential required with state-of-the-art nano-structured photo-anodes by as much as 100 mV and increases the photocurrent by a factor of 3.5 (from 0.24 mA cm-2 to 0.85 mA cm-2) at +1.0 V vs. the reversible hydrogen electrode (RHE) under standard illumination conditions. The subsequent addition of Co2+ ions as a catalyst further decreases the overpotential and leads to a record photocurrent density at 0.9 V vs. RHE (0.42 mA cm-2). A detailed investigation into the effect of the Al2O3 overlayer by electrochemical impedance and photoluminescence spectroscopy reveals a significant change in the surface capacitance and radiative recombination, respectively, which distinguishes the observed overpotential reduction from a catalytic effect and confirms the passivation of surface states. Importantly, this work clearly demonstrates that two distinct loss processes are occurring on the surface of high-performance hematite and suggests a viable route to individually address them. © The Royal Society of Chemistry 2011.

  9. A theoretical study of symmetry-breaking organic overlayers on single- and bi-layer graphene

    Science.gov (United States)

    Morales-Cifuentes, Josue; Einstein, T. L.

    2013-03-01

    An ``overlayer'' of molecules that breaks the AB symmetry of graphene can produce (modify) a band gap in single- (bi-) layer graphene.[2] Since the triangular shaped trimesic acid (TMA) molecule forms two familiar symmetry breaking configurations, we are motivated to model TMA physisorption on graphene surfaces in conjunction with experiments by Groce et al. at UMD. Using VASP, with ab initio van der Waals density functionals (vdW-DF), we simulate adsorption of TMA onto a graphene surface in several symmetry-breaking arrangements in order to predict/understand the effect of TMA adsorption on experimental observables. Supported by NSF-MRSEC Grant DMR 05-20471.

  10. Development of a Mathematical Framework for Comparison of Underlay and Overlay Systems

    Directory of Open Access Journals (Sweden)

    SayedPouriaTalebi

    2013-01-01

    Full Text Available Overlay and underlayare two main spectrum access strategies in cognitive radio.In this work, wehave driven closed form expressions for the primary service outage probabilitiesof both techniques. We have also formulated and solved optimization problems with the objective of maximizing the secondary service’s capacity with constraints on primary service’s outage probability and secondary service power budget. A mathematical frame work for comparing the performance of the two systems has been developed. The performances of the two systems havebeen compared against different levels of primary service interference, activity, and secondary service power budget levels, and the strengths of each system has been clarified

  11. Resource Search in Unstructured Peer-to-Peer System Based on Multiple-Tree Overlay Structure

    Institute of Scientific and Technical Information of China (English)

    YU Jianqiao; LIAO Jianwei

    2007-01-01

    We propose a multiple-tree overlay structure for resource discovery in unstructured P2P systems. Peers that have similar interests or hold similar type of resources will be grouped into a tree-like cluster. We exploit the heterogeneity of peers in each cluster by connecting peers with more capacities closer to the root of the tree. The capacity of a peer can be defined in different ways (e.g. higher network bandwidth, larger disk space, more data items of a certain type etc.) according to different needs of users or applications.

  12. Studying on equilibriums between price and QoS in multi-provider overlay access networks

    Institute of Scientific and Technical Information of China (English)

    Wang Yufeng; Wang Wendong

    2006-01-01

    From the viewpoint of game theory, this paper proposes a model that combines QoS index with price factor in overlay access networks, and uses the multinomial logit (MNL) to model the choice behaviour of users. Each service class is considered an independent and competitive entity offered by each provider,which aims at maximizing its own utility. Based on noncooperative game, we prove the existence and uniqueness of equilibriums between QoS levels and prices among various service classes, and demonstrate the properties of equilibriums. Finally, these results are verified via numerical analysis.

  13. Shadow Segmentation and Augmentation Using á-overlay Models that Account for Penumbra

    DEFF Research Database (Denmark)

    Nielsen, Michael; Madsen, Claus B.

    2006-01-01

    This paper introduces a new concept within shadow segmentation. Previously, an image is considered to consist of shadow and non-shadow regions. Thus, a binary mask is estimated using various heuristics regarding structural and retinex/color constancy theories. We wish to model natural shadows so...... that an augmented virtual object can cast an exact shadow. The penumbras (half-shadows) must be taken into account so that we can model the soft shadows.We hope to achieve this by modelling the shadow regions (umbra and penumbra alike) with a transparent overlay. This paper reviews the state-of-the-art shadow...

  14. The promotion of CO dissociation by molybdenum oxide overlayers on rhodium

    Science.gov (United States)

    Szenti, Imre; Bugyi, László; Kónya, Zoltán

    2017-03-01

    A considerable promotional effect of MoOx species observed at high pressures on the catalytic activity of rhodium initiated the present UHV model study. The MoOx overlayers formed on Rh films (0.15-20.0 ML) supported by TiO2(110) substrate were characterized by AES, TPD, work function (WF) measurements and CO adsorption. On the mixed oxide support produced by depositing 1.2 ML Mo onto TiO2(110), a new recombinative CO desorption state was observed with Tp=700 K, assigned as β-CO and related to the promotional effect of MoOx species diffused onto Rh particles of 1.0 ML coverage. The development of β-CO needs 0.5-0.7 ML threshold Rh coverage, attributable to particle size effect and geometric factors governing the CO adsorption. The β-CO state with Tp=725-742 K could also be detected on Rh films covered by MoOx moiety formed by the oxidation of Mo overlayers in O2. Remarkably, recombinative CO desorption with Tp=700 K could be observed on the Rh nanoparticles covered by MoOzCy produced from pure Mo deposits by CO adsorption, too. In harmony with the promotional effect of MoOx overlayer found at high pressures, it is established that the dissociation of CO is maximal at 0.2-0.3 ML Mo coverage, attributed to the presence of active sites at the oxide-metal interface. The low desorption peak temperature (700 K) of associative CO desorption observed in the presence of MoOx and MoOzCy overlayers indicates a low activation energy for the reactions of Oa and Ca atoms, allowing high reaction rates for these intermediates. The MoOx species exerted both promotion and inhibition effects on CO adsorption at sub-monolayer coverages, but above 1 ML it completely suppressed the reactivity of rhodium layers towards CO, suggesting that its surface concentration is a critical factor.

  15. Research on P2P Overlay Network Model with Small-world Features

    OpenAIRE

    Liu, Hao; Chen, Zhigang

    2013-01-01

    Topology structure of P2P network decides its system performance. However, the existing P2P network models don’t take clustering and symmetry of nodes into account. Based on the algebra and graph theory method of Cayley graph, this paper proposes a novel P2P overlay network model with small-world features. Its simplicity and symmetry can ensure the self-organization and scalability of P2P network. The results of analysis and experiment shows that this model provides better robustness, h...

  16. Super-proximity routing in structured peer-to-peer overlay networks

    Institute of Scientific and Technical Information of China (English)

    吴增德; 饶卫雄; 马范援

    2004-01-01

    Peer-to-Peer systems are emerging as one of the most popular Intemet applications. Structured Peer-to-Peer overlay networks use identifier based routing algorithms to allow robustness, load balancing, and distributed lookup needed in this environment. However, identifier based routing that is independent of Internet topology tends to be of low efficiency. Aimed at improving the routing efficiency, the super-proximity routing algorithms presented in this paper combine Internet topology and over|ay routing table in choosing the next hop. Experimental results showed that the algorithms greatly improve the efficiency of Peer-to-Peer routing.

  17. Catalytic Two-Stage Liquefaction (CTSL{trademark}) process bench studies and PDU scale-up with sub-bituminous coal. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Comolli, A.G.; Johanson, E.S.; Karolkiewicz, W.F.; Lee, L.K.T.; Stalzer, R.H.; Smith, T.O.

    1993-03-01

    Reported are the details and results of Laboratory and Bench-Scale experiments using sub-bituminous coal conducted at Hydrocarbon Research, Inc., under DOE Contract No. DE-AC22-88PC88818 during the period October 1, 1988 to December 31, 1992. The work described is primarily concerned with testing of the baseline Catalytic Two-Stage Liquefaction (CTSL{trademark}) process with comparisons with other two stage process configurations, catalyst evaluations and unit operations such as solid separation, pretreatments, on-line hydrotreating, and an examination of new concepts. In the overall program, three coals were evaluated, bituminous Illinois No. 6, Burning Star and sub-bituminous Wyoming Black Thunder and New Mexico McKinley Mine seams. The results from a total of 16 bench-scale runs are reported and analyzed in detail. The runs (experiments) concern process variables, variable reactor volumes, catalysts (both supported, dispersed and rejuvenated), coal cleaned by agglomeration, hot slurry treatments, reactor sequence, on-line hydrotreating, dispersed catalyst with pretreatment reactors and CO{sub 2}/coal effects. The tests involving the Wyoming and New Mexico Coals are reported herein, and the tests involving the Illinois coal are described in Topical Report No. 2. On a laboratory scale, microautoclave tests evaluating coal, start-up oils, catalysts, thermal treatment, CO{sub 2} addition and sulfur compound effects were conducted and reported in Topical Report No. 3. Other microautoclave tests are described in the Bench Run sections to which they refer such as: rejuvenated catalyst, coker liquids and cleaned coals. The microautoclave tests conducted for modelling the CTSL{trademark} process are described in the CTSL{trademark} Modelling section of Topical Report No. 3 under this contract.

  18. The advantages of S.B.S. modified bituminous membranes; Les avantages des membranes de bitume modifie S.B.S

    Energy Technology Data Exchange (ETDEWEB)

    Faucher, D.

    1995-12-31

    The development of the modified bituminous membrane has resulted in an asphalt that has excellent flexibility, elongation and good weatherliness. By the addition of a variety of polymers, the asphalt acquires rubber like properties, ideal for use in roofing membranes. Modified bitumen is composed of distilled bitumen, styrene- butadiene-styrene polymers and calcium carbonate filler. Fiberglass and non-woven polyester felts are used for support in the manufacturing of the membranes. The membranes offer several advantages over conventional roofing materials including increased longevity, applicability to a wide variety of roofing structures and slopes, reduced weight and easy maintenance. 9 figs.

  19. Detection of rare earth elements in Powder River Basin sub-bituminous coal ash using laser-induced breakdown spectroscopy (LIBS)

    Energy Technology Data Exchange (ETDEWEB)

    Tran, Phuoc [National Energy Technology Lab. (NETL), Pittsburgh, PA, (United State; Mcintyre, Dustin [National Energy Technology Lab. (NETL), Pittsburgh, PA, (United State

    2015-10-01

    We reported our preliminary results on the use of laser-induced breakdown spectroscopy to analyze the rare earth elements contained in ash samples from Powder River Basin sub-bituminous coal (PRB-coal). We have identified many elements in the lanthanide series (cerium, europium, holmium, lanthanum, lutetium, praseodymium, promethium, samarium, terbium, ytterbium) and some elements in the actinide series (actinium, thorium, uranium, plutonium, berkelium, californium) in the ash samples. In addition, various metals were also seen to present in the ash samples

  20. Sphagnum mosses from 21 ombrotrophic bogs in the Athabasca Bituminous Sands region show no significant atmospheric contamination of “heavy metals”

    OpenAIRE

    SHOTYK W.; BELLAND Rene; DUKE John; KEMPTER Heike; KRACHLER MICHAEL; NOERNBERG Tommy; Pelletier, Rick; VILE Melanie; WIEDER Kelman; Zaccone, Claudio; Zhang, Shuangquan

    2014-01-01

    Sphagnum moss was collected from twenty-one ombrotrophic (rain-fed) peat bogs surrounding 39 open pit mines and upgrading facilities of Athabasca Bituminous Sands in Alberta (AB). 40 Compared with contemporary Sphagnum moss from four bogs in rural locations of southern 41 Germany (DE), the AB mosses yielded lower concentrations of Ag, Cd, Ni, Pb, Sb and Tl, 42 similar concentrations of Mo, but greater concentrations of Ba, Th and V. Except for V, 43 compared to the “cleanest”, ancient peat sa...

  1. Use of Hydrogen Chemisorption and Ethylene Hydrogenation as Predictors for Aqueous Phase Reforming of Lactose over Ni@Pt and Co@Pt Bimetallic Overlayer Catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Lai, Qinghua; Skoglund, Michael D.; Zhang, Chen; Morris, Allen R.; Holles, Joseph H.

    2016-10-20

    Overlayer Pt on Ni (Ni@Pt) or Co (Co@Pt) were synthesized and tested for H2 generation from APR of lactose. H2 chemisorption descriptor showed that Ni@Pt and Co@Pt overlayer catalysts had reduced H2 adsorption strength compared to a Pt only catalyst, which agree with computational predictions. The overlayer catalysts also demonstrated lower activity for ethylene hydrogenation than the Pt only catalyst, which likely resulted from decreased H2 binding strength decreasing the surface coverage of H2. XAS results showed that overlayer catalysts exhibited higher white line intensity than the Pt catalyst, which indicates a negative d-band shift for the Pt overlayer, further providing evidence for overlayer formation. Lactose APR studies showed that lactose can be used as feedstock to produce H2 and CO under desirable reaction conditions. The Pt active sites of Ni@Pt and Co@Pt overlayer catalysts showed significantly enhanced H2 production selectivity and activity when compared with that of a Pt only catalyst. The single deposition overlayer with the largest d-band shift showed the highest H2 activity. The results suggest that overlayer formation using directed deposition technique could modify the behavior of the surface metal and ultimately modify the APR activity.

  2. Properties of silicon nitride thin overlays deposited on optical fibers — Effect of fiber suspension in radio frequency plasma-enhanced chemical vapor deposition reactor

    Energy Technology Data Exchange (ETDEWEB)

    Śmietana, M., E-mail: M.Smietana@elka.pw.edu.pl [Institute of Microelectronics and Optoelectronics, Warsaw University of Technology, Koszykowa 75, Warsaw 00-662 (Poland); Dominik, M.; Myśliwiec, M.; Kwietniewski, N. [Institute of Microelectronics and Optoelectronics, Warsaw University of Technology, Koszykowa 75, Warsaw 00-662 (Poland); Mikulic, P. [Centre de Recherche en Photonique, Université du Québec en Outaouais, 101 rue Saint-Jean-Bosco, Gatineau, J8X 3X7, Québec (Canada); Witkowski, B.S. [Institute of Physics, Polish Academy of Sciences, Al. Lotników 32/46, Warsaw 02-666 (Poland); Bock, W.J. [Centre de Recherche en Photonique, Université du Québec en Outaouais, 101 rue Saint-Jean-Bosco, Gatineau, J8X 3X7, Québec (Canada)

    2016-03-31

    This work discusses the effect of sample suspension in radio frequency plasma-enhanced chemical vapor deposition process on properties of the obtained overlays. Silicon nitride (SiN{sub x}) overlays were deposited on flat silicon wafers and cylindrical fused silica optical fibers. The influence of the suspension height and fiber diameter on SiN{sub x} deposition rate is investigated. It has been found that thickness of the SiN{sub x} overlay significantly increases with suspension height, and the deposition rate depends on fiber dimensions. Moreover, the SiN{sub x} overlays were also deposited on long-period gratings (LPGs) induced in optical fiber. Measurements of the LPG spectral response combined with its numerical simulations allowed for a discussion on properties of the deposited overlay. The measurements have proven higher overlay deposition rate on the suspended fiber than on flat Si wafer placed on the electrode. Results of this work are essential for precise tuning of the functional properties of new generations of optical devices such as optical sensors, filters and resonators, which typically are based on optical fibers and require the overlays with well defined properties. - Highlights: • The effect of optical fiber suspension in plasma process is discussed. • The deposition rate of silicon nitride (SiN{sub x}) overlay depends on fiber dimensions. • Thickness of the SiN{sub x} overlay strongly increases with suspension height. • Measurements and simulations of long-period grating confirms experimental results.

  3. Assessment of potential location of high arsenic contamination using fuzzy overlay and spatial anisotropy approach in iron mine surrounding area.

    Science.gov (United States)

    Weerasiri, Thanes; Wirojanagud, Wanpen; Srisatit, Thares

    2014-01-01

    Fuzzy overlay approach on three raster maps including land slope, soil type, and distance to stream can be used to identify the most potential locations of high arsenic contamination in soils. Verification of high arsenic contamination was made by collection samples and analysis of arsenic content and interpolation surface by spatial anisotropic method. A total of 51 soil samples were collected at the potential contaminated location clarified by fuzzy overlay approach. At each location, soil samples were taken at the depth of 0.00-1.00 m from the surface ground level. Interpolation surface of the analysed arsenic content using spatial anisotropic would verify the potential arsenic contamination location obtained from fuzzy overlay outputs. Both outputs of the spatial surface anisotropic and the fuzzy overlay mapping were significantly spatially conformed. Three contaminated areas with arsenic concentrations of 7.19 ± 2.86, 6.60 ± 3.04, and 4.90 ± 2.67 mg/kg exceeded the arsenic content of 3.9 mg/kg, the maximum concentration level (MCL) for agricultural soils as designated by Office of National Environment Board of Thailand. It is concluded that fuzzy overlay mapping could be employed for identification of potential contamination area with the verification by surface anisotropic approach including intensive sampling and analysis of the substances of interest.

  4. Reducing overlay sampling for APC-based correction per exposure by replacing measured data with computational prediction

    Science.gov (United States)

    Noyes, Ben F.; Mokaberi, Babak; Oh, Jong Hun; Kim, Hyun Sik; Sung, Jun Ha; Kea, Marc

    2016-03-01

    One of the keys to successful mass production of sub-20nm nodes in the semiconductor industry is the development of an overlay correction strategy that can meet specifications, reduce the number of layers that require dedicated chuck overlay, and minimize measurement time. Three important aspects of this strategy are: correction per exposure (CPE), integrated metrology (IM), and the prioritization of automated correction over manual subrecipes. The first and third aspects are accomplished through an APC system that uses measurements from production lots to generate CPE corrections that are dynamically applied to future lots. The drawback of this method is that production overlay sampling must be extremely high in order to provide the system with enough data to generate CPE. That drawback makes IM particularly difficult because of the throughput impact that can be created on expensive bottleneck photolithography process tools. The goal is to realize the cycle time and feedback benefits of IM coupled with the enhanced overlay correction capability of automated CPE without impacting process tool throughput. This paper will discuss the development of a system that sends measured data with reduced sampling via an optimized layout to the exposure tool's computational modelling platform to predict and create "upsampled" overlay data in a customizable output layout that is compatible with the fab user CPE APC system. The result is dynamic CPE without the burden of extensive measurement time, which leads to increased utilization of IM.

  5. A nanometric Rh overlayer on a metal foil surface as a highly efficient three-way catalyst

    Science.gov (United States)

    Misumi, Satoshi; Yoshida, Hiroshi; Hinokuma, Satoshi; Sato, Tetsuya; Machida, Masato

    2016-01-01

    Pulsed arc-plasma (AP) deposition of an Rh overlayer on an Fe–Cr–Al stainless steel foil produced a composite material that exhibited high activity for automotive three-way catalysis (TWC). The AP pulses deposited metallic Rh nanoparticles 1–3 nm in size, whose density on the surface increased with the number of pulses. This led to coalescence and grain growth on the foil surface and the eventual formation of a uniform two-dimensional Rh overlayer. Full coverage of the 51 μm-thick flat foil by a 3.2 nm-thick Rh overlayer was achieved after 1,000 pulses. A simulated TWC reaction using a miniature honeycomb fabricated using flat and corrugated foils with the Rh overlayers exhibited successful light-off at a practical gaseous hourly space velocity of 1.2 × 105 h−1. The turnover frequency for the NO–CO reaction over the metallic honeycomb catalyst was ca. 80-fold greater than that achieved with a reference Rh/ZrO2-coated cordierite honeycomb prepared using a conventional wet impregnation and slurry coating procedure. Despite the nonporosity and low surface area of the foil-supported Rh overlayer compared with conventional powder catalysts (Rh/ZrO2), it is a promising alternative design for more efficient automotive catalysts that use less Rh loading. PMID:27388976

  6. A nanometric Rh overlayer on a metal foil surface as a highly efficient three-way catalyst

    Science.gov (United States)

    Misumi, Satoshi; Yoshida, Hiroshi; Hinokuma, Satoshi; Sato, Tetsuya; Machida, Masato

    2016-07-01

    Pulsed arc-plasma (AP) deposition of an Rh overlayer on an Fe–Cr–Al stainless steel foil produced a composite material that exhibited high activity for automotive three-way catalysis (TWC). The AP pulses deposited metallic Rh nanoparticles 1–3 nm in size, whose density on the surface increased with the number of pulses. This led to coalescence and grain growth on the foil surface and the eventual formation of a uniform two-dimensional Rh overlayer. Full coverage of the 51 μm-thick flat foil by a 3.2 nm-thick Rh overlayer was achieved after 1,000 pulses. A simulated TWC reaction using a miniature honeycomb fabricated using flat and corrugated foils with the Rh overlayers exhibited successful light-off at a practical gaseous hourly space velocity of 1.2 × 105 h‑1. The turnover frequency for the NO–CO reaction over the metallic honeycomb catalyst was ca. 80-fold greater than that achieved with a reference Rh/ZrO2-coated cordierite honeycomb prepared using a conventional wet impregnation and slurry coating procedure. Despite the nonporosity and low surface area of the foil-supported Rh overlayer compared with conventional powder catalysts (Rh/ZrO2), it is a promising alternative design for more efficient automotive catalysts that use less Rh loading.

  7. Assessment of Potential Location of High Arsenic Contamination Using Fuzzy Overlay and Spatial Anisotropy Approach in Iron Mine Surrounding Area

    Directory of Open Access Journals (Sweden)

    Thanes Weerasiri

    2014-01-01

    Full Text Available Fuzzy overlay approach on three raster maps including land slope, soil type, and distance to stream can be used to identify the most potential locations of high arsenic contamination in soils. Verification of high arsenic contamination was made by collection samples and analysis of arsenic content and interpolation surface by spatial anisotropic method. A total of 51 soil samples were collected at the potential contaminated location clarified by fuzzy overlay approach. At each location, soil samples were taken at the depth of 0.00-1.00 m from the surface ground level. Interpolation surface of the analysed arsenic content using spatial anisotropic would verify the potential arsenic contamination location obtained from fuzzy overlay outputs. Both outputs of the spatial surface anisotropic and the fuzzy overlay mapping were significantly spatially conformed. Three contaminated areas with arsenic concentrations of 7.19±2.86, 6.60±3.04, and 4.90±2.67 mg/kg exceeded the arsenic content of 3.9 mg/kg, the maximum concentration level (MCL for agricultural soils as designated by Office of National Environment Board of Thailand. It is concluded that fuzzy overlay mapping could be employed for identification of potential contamination area with the verification by surface anisotropic approach including intensive sampling and analysis of the substances of interest.

  8. Optimización multiobjetivo para enrutamiento multicast en overlay networks utilizando algoritmos evolutivos Multiobjective Optimization for Multicast Routing in Overlay Networks using Evolutionary Algorithms

    Directory of Open Access Journals (Sweden)

    Juan Carlos Montoya M.

    2008-06-01

    Full Text Available Multicast juega un papel muy importante para soportar una nueva generación de aplicaciones. En la actualidad y por diferentes razones, técnicas y no técnicas, multicast IP no ha sido totalmente adoptado en Internet. Durante los últimos a˜nos, un área de investigación activa es la de implementar este tipo de tráfico desde la perspectiva del nivel de aplicación, donde la funcionalidad de multicast no es responsabilidad de los enrutadores sino de los hosts, a lo que se le conoce como Multicast Overlay Network (MON. En este artículo se plantea el enrutamiento en MON como un problema de Optimización Multiobjetivo (MOP donde se optimizan dos funciones: 1 el retardo total extremo a extremo del árbol multicast, y 2 la máxima utilización de los enlaces. La optimización simultánea de estas dos funciones es un problema NP completo y para resolverlo se propone utilizar Algoritmos Evolutivos Multiobjetivos (MOEA, específicamente NSGAIMulticast plays an important role in supporting a new generation of applications. At present and for different reasons, technical and non–technical, multicast IP hasn’t yet been totally adopted for Internet. During recent years, an active area of research is that of implementing this kind of traffic in the application layer where the multicast functionality isn´t a responsibility of the routers but that of the hosts, which we know as Multicast Overlay Networks (MON. In this article, routing in an MON is put forward as a multiobjective optimization problem (MOP where two functions are optimized: 1 the total end to end delay of the multicast tree and 2 the maximum link utilization. The simultaneous optimization of these two functions is an NP–Complete problem and to solve this we suggest using Multiobjective Evolutionary Algorithms (MOEA, specifically NSGA–II.

  9. Progressive oxidation of pyrite in five bituminous coal samples: An As XANES and 57Fe Mössbauer spectroscopic study

    Science.gov (United States)

    Kolker, Allan; Huggins, Frank E.

    2007-01-01

    Naturally occurring pyrite commonly contains minor substituted metals and metalloids (As, Se, Hg, Cu, Ni, etc.) that can be released to the environment as a result of its weathering. Arsenic, often the most abundant minor constituent in pyrite, is a sensitive monitor of progressive pyrite oxidation in coal. To test the effect of pyrite composition and environmental parameters on the rate and extent of pyrite oxidation in coal, splits of five bituminous coal samples having differing amounts of pyrite and extents of As substitution in the pyrite, were exposed to a range of simulated weathering conditions over a period of 17 months. Samples investigated include a Springfield coal from Indiana (whole coal pyritic S = 2.13 wt.%; As in pyrite = detection limit (d.l.) to 0.06 wt.%), two Pittsburgh coal samples from West Virginia (pyritic S = 1.32–1.58 wt.%; As in pyrite = d.l. to 0.34 wt.%), and two samples from the Warrior Basin, Alabama (pyritic S = 0.26–0.27 wt.%; As in pyrite = d.l. to 2.72 wt.%). Samples were collected from active mine faces, and expected differences in the concentration of As in pyrite were confirmed by electron microprobe analysis. Experimental weathering conditions in test chambers were maintained as follows: (1) dry Ar atmosphere; (2) dry O2 atmosphere; (3) room atmosphere (relative humidity ∼20–60%); and (4) room atmosphere with samples wetted periodically with double-distilled water. Sample splits were removed after one month, nine months, and 17 months to monitor the extent of As and Fe oxidation using As X-ray absorption near-edge structure (XANES) spectroscopy and 57Fe Mössbauer spectroscopy, respectively. Arsenic XANES spectroscopy shows progressive oxidation of pyritic As to arsenate, with wetted samples showing the most rapid oxidation. 57Fe Mössbauer spectroscopy also shows a much greater proportion of Fe3+ forms (jarosite, Fe3+ sulfate, FeOOH) for samples stored under wet conditions, but much less

  10. Controls on coalbed methane potential and gas sorption characteristics of high-volatile bituminous coals in Indiana

    Science.gov (United States)

    Solano-Acosta, Wilfrido

    distribution, and adsorption experiments at high and low gas pressures are employed to estimate reservoir gas capacity and to characterize high volatile bituminous coals of Indiana for potential future CO2 sequestration. Understanding the mechanisms and geologic conditions that control the occurrence of gas in coal allows us to better characterize: (1) CBM reservoirs for their potential economic use, and (2) coal seams as future receptacles of anthropogenic carbon dioxide.

  11. Optical fibre long period grating spectral actuators utilizing ferrofluids as outclading overlayers

    Science.gov (United States)

    Konstantaki, M.; Candiani, A.; Pissadakis, S.

    2011-03-01

    Results are presented on the spectral tuning of optical fibre long period gratings utilizing water and oil based ferrofluids as outclading overlayers, under static magnetic field stimulus. Two approaches are adopted for modifying the ambient refractive index at the position of the long period grating. In the first approach, a water based ferrofluid is controllably translated along the length of the grating via a magnetic field. Changes as high as 7.5nm and 6.5dB are monitored in the wavelength and strength, respectively, of the attenuation bands of the grating. The repeatable performance of this device for repetitive forward and backward translation verifies that no ferrofluidic residue is left on the fibre, due to silanization cladding functionalisation. In the second approach, the refractive index of an oil based ferrofluidic overlayer is modified through the magneto-optical effect. For an applied static magnetic field in the order of 400 Gauss the strength of the attenuation band of the grating is modified by more than 10% while its spectral position remains unaffected. Accordingly for the implementation of the last approach, the magnetically induced refractive index changes of ferrofluids of different solution concentrations are studied by employing diffraction efficiency measurements.

  12. TORSIONAL VIBRATIONS OF A RIGID CIRCULAR PLATE ON SATURATED STRATUM OVERLAYING BEDROCK

    Institute of Scientific and Technical Information of China (English)

    CaiYuanqiang; WuDazhi; XuChangjie

    2005-01-01

    The torsional vibration of a rigid plate resting on saturated stratum overlaying bedrock has been analysed for the first time. The dynamic governing differential equations for saturated poroelastic medium are solved by employing the technology of Hankel transform. By taking into account the boundary conditions, the dual integral equations of torsional vibration of a rigid circular plate are established, which are further converted into a Fredholm integral equation of the second kind. Subsequently, the dynamic compliance coefficients of the foundation on saturated stratum, the contact shear stress under the foundation and the angular amplitude of the foundation are evaluated. Numerical results indicate that, when the dimensionless height is bigger than 5, saturated stratum overlaying bedrock can be treated as saturated half space approximately. When the dimensionless frequency is low, the permeability of the soil must be taken into account. Furthermore, when the vibration frequency is a constant, the height of the saturated stratum has a slight effect on the dimensionless contact shear stress under the foundation.

  13. A high-accuracy surgical augmented reality system using enhanced integral videography image overlay.

    Science.gov (United States)

    Zhang, Xinran; Chen, Guowen; Liao, Hongen

    2015-01-01

    Image guided surgery has been used in clinic to improve the surgery safety and accuracy. Augmented reality (AR) technique, which can provide intuitive image guidance, has been greatly evolved these years. As one promising approach of surgical AR systems, integral videography (IV) autostereoscopic image overlay has achieved accurate fusion of full parallax guidance into surgical scene. This paper describes an image enhanced high-accuracy IV overlay system. A flexible optical image enhancement system (IES) is designed to increase the resolution and quality of IV image. Furthermore, we introduce a novel IV rendering algorithm to promote the spatial accuracy with the consideration of distortion introduced by micro lens array. Preliminary experiments validated that the image accuracy and resolution are improved with the proposed methods. The resolution of the IV image could be promoted to 1 mm for a micro lens array with pitch of 2.32 mm and IES magnification value of 0.5. The relative deviation of accuracy in depth and lateral directions are -4.68 ± 0.83% and -9.01 ± 0.42%.

  14. The Effects of a Dynamic Spectrum Access Overlay in LTE-Advanced Networks

    Energy Technology Data Exchange (ETDEWEB)

    Juan D. Deaton; Ryan E. lrwin; Luiz A. DaSilva

    2011-05-01

    As early as 2014, wireless network operators spectral capacity will be overwhelmed by a data tsunami brought on by new devices and applications. To augment spectral capacity, operators could deploy a Dynamic Spectrum Access (DSA) overlay. In the light of the many planned Long Term Evolution (LTE) network deployments, the affects of a DSA overlay have not been fully considered into the existing LTE standards. Coalescing many different aspects of DSA, this paper develops the Spectrum Accountability (SA) framework. The SA framework defines specific network element functionality, protocol interfaces, and signaling flow diagrams for LTE to support service requests and enforce rights of responsibilities of primary and secondary users, respectively. We also include a network simulation to quantify the benefits of using DSA channels to augment capacity. Based on our simulation we show that, network operators can benefit up to %40 increase in operating capacity when sharing DSA bands to augment spectral capacity. With our framework, this paper could serve as an guide in developing future LTE network standards that include DSA.

  15. Stability and calibration of overlay and focus control for a double patterning immersion scanner

    Science.gov (United States)

    Yasuda, Masahiko; Wakamoto, Shinji; Imagawa, Hiroto; Takubo, Shinya; Shiba, Yuuji; Kikuchi, Takahisa; Shirata, Yosuke; Ishii, Yuuki

    2011-04-01

    To achieve the 2 nm overlay accuracy required for double patterning, we have introduced the NSR-S620D immersion scanner that employs an encoder metrology system. The key challenges for an encoder metrology system include its stability as well as the methods of calibration. The S620D has a hybrid metrology system consisting of encoders and interferometers, in XY and Z. The advantage of a hybrid metrology system is that we can continuously monitor the position of the stage using both encoders and interferometers for optimal positioning control, without any additional metrology requirements or throughput loss. To support this technology, the S620D has various encoder calibration functions that make and maintain the ideal grid, and control focus. In this paper we will introduce some of the encoder calibration functions based on the interferometer. We also provide the latest performance of the tool, with an emphasis on overlay and focus control, validating that the NSR-S620D delivers the necessary levels of accuracy and stability for the production phase of double patterning.

  16. Bandwidth and power allocation for two-way relaying in overlay cognitive radio systems

    KAUST Repository

    Alsharoa, Ahmad M.

    2014-12-01

    In this paper, the problem of both bandwidth and power allocation for two-way multiple relay systems in overlay cognitive radio (CR) setup is investigated. In the CR overlay mode, primary users (PUs) cooperate with cognitive users (CUs) for mutual benefits. In our framework, we propose that the CUs are allowed to allocate a part of the PUs spectrum to perform their cognitive transmission. In return, acting as an amplify-and-forward two-way relays, they are used to support PUs to achieve their target data rates over the remaining bandwidth. More specifically, CUs acts as relays for the PUs and gain some spectrum as long as they respect a specific power budget and primary quality-of-service constraints. In this context, we first derive closed-form expressions for optimal transmit power allocated to PUs and CUs in order to maximize the cognitive objective. Then, we employ a strong optimization tool based on particle swarm optimization algorithm to find the optimal relay amplification gains and optimal cognitive released bandwidths as well. Our numerical results illustrate the performance of our proposed algorithm for different utility metrics and analyze the impact of some system parameters on the achieved performance.

  17. Overlay coating degradation by simultaneous oxidation and coating/substrate interdiffusion. Ph.D. Thesis

    Science.gov (United States)

    Nesbitt, J. A.

    1983-01-01

    Degradation of NiCrAlZr overlay coatings on various NiCrAl substrates was examined after cyclic oxidation. Concentration/distance profiles were measured in the coating and substrate after various oxidation exposures at 1150 C. For each stubstrate, the Al content in the coating decreased rapidly. The concentration/distance profiles, and particularly that for Al, reflected the oxide spalling resistance of each coated substrate. A numerical model was developed to simulate diffusion associated with overlay-coating degradation by oxidation and coating/substrate interdiffusion. Input to the numerical model consisted of the Cr and Al content of the coating and substrate, ternary diffusivities, and various oxide spalling parameters. The model predicts the Cr and Al concentrations in the coating and substrate after any number of oxidation/thermal cycles. The numerical model also predicts coating failure based on the ability of the coating to supply sufficient Al to the oxide scale. The validity of the model was confirmed by comparison of the predicted and measured concentration/distance profiles. The model was subsequently used to identify the most critical system parameters affecting coating life.

  18. Improving Management Performance of P2PSIP for Mobile Sensing in Wireless Overlays

    Directory of Open Access Journals (Sweden)

    José María Pousada-Carballo

    2013-11-01

    Full Text Available Future wireless communications are heading towards an all-Internet Protocol (all-IP design, and will rely on the Session Initiation Protocol (SIP to manage services, such as voice over IP (VoIP. The centralized architecture of traditional SIP has numerous disadvantages for mobile ad hoc services that may be possibly overcome by advanced peer-to-peer (P2P technologies initially developed for the Internet. In the context of mobile sensing, P2PSIP protocols facilitate decentralized and fast communications with sensor-enabled terminals. Nevertheless, in order to make P2PSIP protocols feasible in mobile sensing networks, it is necessary to minimize overhead transmissions for signaling purposes, which reduces the battery lifetime. In this paper, we present a solution to improve the management of wireless overlay networks by defining an adaptive algorithm for the calculation of refresh time. The main advantage of the proposed algorithm is that it takes into account new parameters, such as the delay between nodes, and provides satisfactory performance and reliability levels at a much lower management overhead than previous approaches. The proposed solution can be applied to many structured P2P overlays or P2PSIP protocols. We evaluate it with Kademlia-based distributed hash tables (DHT and dSIP.

  19. How a gold substrate can increase the reactivity of a Pt overlayer

    DEFF Research Database (Denmark)

    Pedersen, Morten Ø.; Helveg, Stig; Ruban, Andrei

    1999-01-01

    The growth and chemical reactivity of Pt on Au(111) have been studied using scanning tunneling microscopy (STM) and temperature programmed desorption (TPD). Deposition of Pt at coverages from 0.02 ML up to 2.5 ML on Au(111) at room temperature initially leads to the formation of a surface alloy......, in which 3% of the Au atoms are replaced by Pt. Subsequent Pt evaporation leads to island growth with a mixed Pt-Au island composition. The reactivity of the Pt/Au system is studied using CO as a probe molecule. We show that a stronger bonding of CO to the first layer of Pt on Au(111) exists compared...... with the binding of CO on clean Pt. The Au substrate therefore very surprisingly increases the Pt overlayer reactivity. The results can be understood in a simple model, in which the change in the CO binding energy is directly proportional to the shift of the d-band center of the metal overlayer. According...

  20. Electron coincidence studies of sulfur-overlayers on Cu(001) and Ni(001) surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Di Filippo, G., E-mail: gianluca.filippo@fau.de [Max-Planck Institut für Mikrostrukturphysik, Weinberg 2, 06120 Halle (Germany); Schumann, F.O.; Patil, S.; Wei, Z. [Max-Planck Institut für Mikrostrukturphysik, Weinberg 2, 06120 Halle (Germany); Stefani, G. [CNISM and Dipartimento di Scienze, Università Roma Tre, Via della Vasca Navale 84, 00146 Rome (Italy); Fratesi, G. [Dipartimento di Fisica, Università degli Studi di Milano, Via Celoria 16, 20133 Milan (Italy); Trioni, M.I. [CNR – National Research Council of Italy, ISTM, Via Golgi 19, 20133 Milan (Italy); Kirschner, J. [Max-Planck Institut für Mikrostrukturphysik, Weinberg 2, 06120 Halle (Germany)

    2016-08-15

    Highlights: • The LVV Auger decay of different sulfur-overlayers is investigated. • The decay can be described within a two-step model. • The Auger line shapes furnish information on the electronic structure at the surface. • The e–e correlation energy is hardly affected by coverage or substrate variations. - Abstract: We have prepared different sulfur-overlayers on Cu(001) and Ni(001) surfaces which differ in their coverage and local environment of the S adatoms. Via photon absorption we excited the S 2p level and studied the subsequent Auger decay with a coincidence spectrometer. We discuss the variation of the coincidence rate as a function of the energy sum of the photo-Auger electron pair. This is linked to the binding energy of the double-hole state. We find that the photon energy has no dramatic influence on the spectra. Differences are observed when the local environment of sulfur is changed. The observed spectral changes are mainly ascribable to the variation of the density of states at the different surfaces. On the contrary, the strength of electron–electron correlation at the surface states is hardly affected by coverage or substrate variation.

  1. A comparative study between xerographic, computer-assisted overlay generation and animated-superimposition methods in bite mark analyses.

    Science.gov (United States)

    Tai, Meng Wei; Chong, Zhen Feng; Asif, Muhammad Khan; Rahmat, Rabiah A; Nambiar, Phrabhakaran

    2016-09-01

    This study was to compare the suitability and precision of xerographic and computer-assisted methods for bite mark investigations. Eleven subjects were asked to bite on their forearm and the bite marks were photographically recorded. Alginate impressions of the subjects' dentition were taken and their casts were made using dental stone. The overlays generated by xerographic method were obtained by photocopying the subjects' casts and the incisal edge outlines were then transferred on a transparent sheet. The bite mark images were imported into Adobe Photoshop® software and printed to life-size. The bite mark analyses using xerographically generated overlays were done by comparing an overlay to the corresponding printed bite mark images manually. In computer-assisted method, the subjects' casts were scanned into Adobe Photoshop®. The bite mark analyses using computer-assisted overlay generation were done by matching an overlay and the corresponding bite mark images digitally using Adobe Photoshop®. Another comparison method was superimposing the cast images with corresponding bite mark images employing the Adobe Photoshop® CS6 and GIF-Animator©. A score with a range of 0-3 was given during analysis to each precision-determining criterion and the score was increased with better matching. The Kruskal Wallis H test showed significant difference between the three sets of data (H=18.761, p<0.05). In conclusion, bite mark analysis using the computer-assisted animated-superimposition method was the most accurate, followed by the computer-assisted overlay generation and lastly the xerographic method. The superior precision contributed by digital method is discernible despite the human skin being a poor recording medium of bite marks.

  2. Conceptual overlays for urban soundscape design emerging from a transversal analysis of Lefebvre, Deleuze and Guattari, and Arendt

    Directory of Open Access Journals (Sweden)

    Jordan Lacey

    2013-12-01

    Full Text Available This paper describes theoretical developments that have emerged alongside the author’s urban soundscape design practice. The theory, which emerged from a transversal analysis of Henri Lefebvre, Gilles Deleuze and Felix Guattari, and Hannah Arendt, particularly their philosophical investigations of space, rhythm and nature, is presented as four conceptual overlays to aid soundscape design practices in urban spaces. The first conceptual overlay, Radiating Striations of Centralities, synthesises spatial discussions of Deleuze and Guattari and Lefebvre into soundscape design approaches that simultaneously respond to centralized controls and the peripheries of urban spaces. The second conceptual overlay, The Isorhythimc Refrain, convolves Deleuze and Guattari’s refrain and Lefebvre’s isorhythms into identifiable socially controlling rhythms that unfold as captured sonic and gestural forms throughout urban spaces. The third conceptual overlay, Altered Soundscapes as Emergent Ecologies, investigates Guattari’s a-signifying rupture and the potential of soundscape design as rupture to affect the emergence of Lefebvre’s new nature(s in urban spaces. The fourth conceptual overlay, Disassembling the Collective Assemblage of Enunciation, discusses Arendt’s reflections on social rhythms subsuming society into automated behaviour, and the challenges that can be presented to such automated behaviour through the act of soundscape design. The four conceptual overlays provide sociopolitical and ecological understandings of the urban that contribute to a soundscape design practice from which public soundscape installations are created to subvert controlling spatiotemporal rhythms of the urban for the emergence of new nature(s. The article concludes by suggesting that due to the amorphous characteristics of sound the soundscape designer is in a unique position to affect immediate sociopolitical and experiential transformations of urban spaces.

  3. Preconversion processing of bituminous coals: New directions to improved direct catalytic coal liquefaction. Quarterly report, January 1, 1992--March 31, 1992

    Energy Technology Data Exchange (ETDEWEB)

    1992-07-01

    A study of the high-temperature soaking started in this quarter, following the installation of reactors in the previous quarter. Two high-volatile bituminous coals and three coal liquids, which were identified in the previous report, were used. A cross-linked, three-dimensional macromolecular model has been widely accepted f or the structure of coal, but there is no direct evidence to prove this model. The conventional coal structure model has been recently re-examined by this investigator because of the importance of relatively strong intra- and intermolecular interactions in bituminous coals. It was reasonable to deduce that significant portions were physically associated after a study of multistep extractions, associative equilibria, the irreversibility and the dependence of coal concentration on solvent swelling, and consideration of the monophase concept. Physical dissociation which may be significant above 300{degree}C should be utilized for the treatment before liquefaction. The high-temperature soaking in a recycle oil was proposed to dissociate coal complexes.

  4. Preconversion processing of bituminous coals: New directions to improved direct catalytic coal liquefaction. [Effect of preconversion heat soak with coal liquids

    Energy Technology Data Exchange (ETDEWEB)

    1992-07-01

    A study of the high-temperature soaking started in this quarter, following the installation of reactors in the previous quarter. Two high-volatile bituminous coals and three coal liquids, which were identified in the previous report, were used. A cross-linked, three-dimensional macromolecular model has been widely accepted f or the structure of coal, but there is no direct evidence to prove this model. The conventional coal structure model has been recently re-examined by this investigator because of the importance of relatively strong intra- and intermolecular interactions in bituminous coals. It was reasonable to deduce that significant portions were physically associated after a study of multistep extractions, associative equilibria, the irreversibility and the dependence of coal concentration on solvent swelling, and consideration of the monophase concept. Physical dissociation which may be significant above 300{degree}C should be utilized for the treatment before liquefaction. The high-temperature soaking in a recycle oil was proposed to dissociate coal complexes.

  5. Inhibiting effect of [HOEmim][BF4] and [Amim]Cl ionic liquids on the cross-linking reaction of bituminous coal

    Institute of Scientific and Technical Information of China (English)

    Wang Lanyun; Xu Yongliang; Wang Shaokun; Song Zhipeng

    2016-01-01

    In order to reduce the hazard of coal spontaneous combustion, the cross-linking reaction between O-containing functional groups of coal should be inhibited. So the inhibitory effect of an ionic liquid (IL) on the cross-linking reaction was studied. The O-containing functional groups change the weight loss and H2O, CO2, CO yields of bituminous coal before and after [HOEmim][BF4] and [Amim]Cl pre-treatment and were detected by Fourier Transform Infrared spectroscopy (FTIR) and Thermo Gravimetric (TG) anal-ysis. The results show that [Amim]Cl has a weaker ability to inhibit the cross-linking reaction of bitumi-nous coal compared to [HOEmim][BF4]. Besides, based on Quantum Chemistry calculation, it was found that the different inhibiting effects of [HOEmim][BF4] and [Amim]Cl are greatly related to their anions and the H linked with C2 atom on the imidazole ring. The H-donor ability of coal will be enhanced by [HOEmim][BF4] leading to a weaker cross-linking reaction of coal.

  6. Multifunctional bowtie-shaped ridge aperture for overlay alignment in plasmonic direct writing lithography using a contact probe.

    Science.gov (United States)

    Oh, Seonghyeon; Lee, Taekyong; Hahn, Jae W

    2013-07-01

    We propose a scheme of overlay alignment for plasmonic lithography using a scanning contact probe. Using two resonances of a ridge aperture in a metal film, we introduce the aperture's multifunctional characteristics for patterning and alignment at different wavelengths. To verify this idea, we measure an image of an alignment mark using a scanning ridge aperture and determine the reference point for the alignment. We then analyze the uncertainty of the alignment method with respect to the image data noise and compare the numerical results with the experimental results. The uncertainty of the overlay alignment method is shown to be less than approximately 2 nm.

  7. Structural analyses of a rigid pavement overlaying a sub-surface void

    Science.gov (United States)

    Adam, Fatih Alperen

    Pavement failures are very hazardous for public safety and serviceability. These failures in pavements are mainly caused by subsurface voids, cracks, and undulation at the slab-base interface. On the other hand, current structural analysis procedures for rigid pavement assume that the slab-base interface is perfectly planar and no imperfections exist in the sub-surface soil. This assumption would be violated if severe erosion were to occur due to inadequate drainage, thermal movements, and/or mechanical loading. Until now, the effect of erosion was only considered in the faulting performance model, but not with regards to transverse cracking at the mid-slab edge. In this research, the bottom up fatigue cracking potential, caused by the combined effects of wheel loading and a localized imperfection in the form of a void below the mid-slab edge, is studied. A robust stress and surface deflection analysis was also conducted to evaluate the influence of a sub-surface void on layer moduli back-calculation. Rehabilitative measures were considered, which included a study on overlay and fill remediation. A series regression of equations was proposed that provides a relationship between void size, layer moduli stiffness, and the overlay thickness required to reduce the stress to its original pre-void level. The effect of the void on 3D pavement crack propagation was also studied under a single axle load. The amplifications to the stress intensity was shown to be high but could be mitigated substantially if stiff material is used to fill the void and impede crack growth. The pavement system was modeled using the commercial finite element modeling program Abaqus RTM. More than 10,000 runs were executed to do the following analysis: stress analysis of subsurface voids, E-moduli back-calculation of base layer, pavement damage calculations of Beaumont, TX, overlay thickness estimations, and mode I crack analysis. The results indicate that the stress and stress intensity are, on

  8. Creating Interactive Graphical Overlays in the Advanced Weather Interactive Processing System Using Shapefiles and DGM Files

    Science.gov (United States)

    Barrett, Joe H., III; Lafosse, Richard; Hood, Doris; Hoeth, Brian

    2007-01-01

    Graphical overlays can be created in real-time in the Advanced Weather Interactive Processing System (AWIPS) using shapefiles or Denver AWIPS Risk Reduction and Requirements Evaluation (DARE) Graphics Metafile (DGM) files. This presentation describes how to create graphical overlays on-the-fly for AWIPS, by using two examples of AWIPS applications that were created by the Applied Meteorology Unit (AMU) located at Cape Canaveral Air Force Station (CCAFS), Florida. The first example is the Anvil Threat Corridor Forecast Tool, which produces a shapefile that depicts a graphical threat corridor of the forecast movement of thunderstorm anvil clouds, based on the observed or forecast upper-level winds. This tool is used by the Spaceflight Meteorology Group (SMG) at Johnson Space Center, Texas and 45th Weather Squadron (45 WS) at CCAFS to analyze the threat of natural or space vehicle-triggered lightning over a location. The second example is a launch and landing trajectory tool that produces a DGM file that plots the ground track of space vehicles during launch or landing. The trajectory tool can be used by SMG and the 45 WS forecasters to analyze weather radar imagery along a launch or landing trajectory. The presentation will list the advantages and disadvantages of both file types for creating interactive graphical overlays in future AWIPS applications. Shapefiles are a popular format used extensively in Geographical Information Systems. They are usually used in AWIPS to depict static map backgrounds. A shapefile stores the geometry and attribute information of spatial features in a dataset (ESRI 1998). Shapefiles can contain point, line, and polygon features. Each shapefile contains a main file, index file, and a dBASE table. The main file contains a record for each spatial feature, which describes the feature with a list of its vertices. The index file contains the offset of each record from the beginning of the main file. The dBASE table contains records for each

  9. Behaviour of Parallel Coupled Microstrip Band Pass Filter and Simple Microstripline due to Thin-Film Al2O3 Overlay

    Directory of Open Access Journals (Sweden)

    S. B. Rane

    1996-01-01

    Full Text Available The X-band behaviour of a seven-section parallel-coupled microstrip band pass filter and microstripline due to thin-film Al2O3 overlay of different thickness is reported in this paper. This Al2O3 film can give a homogeneous overlay structure. There is a substantial increase in the bandwidth due to the overlay, the pass band extending towards higher frequency side. In most of the cases, an increase in the pass band transmittance of a microstripline also increases due to a thin-film Al2O3 overlay, especially for frequencies less than 9.0 GHz. At higher frequencies, random variations are observed. It is felt that thin-film overlays can be used to modify the microstripline circuit properties, thereby avoiding costly and time consuming elaborate design procedures.

  10. Osmosis-induced water uptake by Eurobitum bituminized radioactive waste and pressure development in constant volume conditions

    Science.gov (United States)

    Mariën, A.; Mokni, N.; Valcke, E.; Olivella, S.; Smets, S.; Li, X.

    2013-01-01

    The chemo-hydro-mechanical (CHM) interaction between swelling Eurobitum radioactive bituminized waste (BW) and Boom Clay is investigated to assess the feasibility of geological disposal for the long-term management of this waste. These so-called compatibility studies include laboratory water uptake tests at the Belgian Nuclear Research Center SCK•CEN, and the development of a coupled CHM formulation for Eurobitum by the International Center for Numerical Methods and Engineering (CIMNE, Polytechnical University of Cataluña, Spain). In the water uptake tests, the osmosis-induced swelling, pressure increase and NaNO3 leaching of small cylindrical BW samples (diameter 38 mm, height 10 mm) is studied under constant total stress conditions and nearly constant volume conditions; the actual geological disposal conditions should be intermediate between these extremes. Two nearly constant volume tests were stopped after 1036 and 1555 days to characterize the morphology of the hydrated BW samples and to visualize the hydrated part with microfocus X-ray Computer Tomography (μCT) and Environmental Scanning Electron Microscopy (ESEM). In parallel, a coupled CHM formulation is developed that describes chemically and hydraulically coupled flow processes in porous materials with salt crystals, and that incorporates a porosity dependent membrane efficiency, permeability and diffusivity. When Eurobitum BW is hydrated in (nearly) constant volume conditions, the osmosis-induced water uptake results in an increasing pressure to values that can be (in theory) as high as 42.8 MPa, being the osmotic pressure of a saturated NaNO3 solution. After about four years of hydration in nearly constant volume water uptake tests, pressures up to 20 MPa are measured. During this hydration period only the outer layers with a thickness of 1-2 mm were hydrated (as derived from μCT and ESEM analyses), and only about 10-20% of the initial NaNO3 content was released by the samples. In the studied test

  11. Adlayer Core-Level Shifts of Random Metal Overlayers on Transition-Metal Substrates

    DEFF Research Database (Denmark)

    Ganduglia-Pirovano, M. V.; Kudrnovský, J.; Scheffler, M.

    1997-01-01

    We calculate the difference of the ionization energies of a core electron of a surface alloy, i.e., a B atom in a A(1-x)B(x) overlayer on a fee B(001) substrate, and a core electron of the clean fee B(001) surface using density-functional theory. We analyze the initial-state contributions and the...... the initial-state trends are explained in terms of the change of inter- and intra-atomic screening upon alloying. A possible role of alloying on the chemical reactivity of metal surfaces is discussed....... and the screening effects induced by the core hole, and study the influence of the alloy composition for a number of noble metal-transition metal systems. Our analysis clearly indicates the importance of final-state screening effects for the interpretation of measured core-level shifts. Calculated deviations from...

  12. Prosthodontic management of segmental mandibulectomy patient with guidance appliance and overlay denture.

    Science.gov (United States)

    Aruna, U; Thulasingam, C

    2013-12-01

    Patients who undergo segmental or hemi-mandibulectomy suffer from various postoperative problems in esthetics and function. The solution to such problem is providing a mandibular guidance appliance to correct mandibular deviation to resected side due to loss of muscle action on the affected side. This article describes the treatment of a female patient who underwent segmental mandibulectomy on right side secondary to adenoid cystic carcinoma of the base of tongue. An acrylic guidance appliance was constructed to help control the mandibular deviation and co-ordinate masticatory movements. The prosthesis was worn continuously by the patient for 1 month which corrected the occlusion on the left side. To compensate for the open-bite caused due to rotation of mandible following partial mandibulectomy, an overlay removable partial denture was given. The patient was satisfied with the improvement in esthetics and mastication.

  13. Secret Forwarding of Events over Distributed Publish/Subscribe Overlay Network.

    Science.gov (United States)

    Yoon, Young; Kim, Beom Heyn

    2016-01-01

    Publish/subscribe is a communication paradigm where loosely-coupled clients communicate in an asynchronous fashion. Publish/subscribe supports the flexible development of large-scale, event-driven and ubiquitous systems. Publish/subscribe is prevalent in a number of application domains such as social networking, distributed business processes and real-time mission-critical systems. Many publish/subscribe applications are sensitive to message loss and violation of privacy. To overcome such issues, we propose a novel method of using secret sharing and replication techniques. This is to reliably and confidentially deliver decryption keys along with encrypted publications even under the presence of several Byzantine brokers across publish/subscribe overlay networks. We also propose a framework for dynamically and strategically allocating broker replicas based on flexibly definable criteria for reliability and performance. Moreover, a thorough evaluation is done through a case study on social networks using the real trace of interactions among Facebook users.

  14. GaAs wafer overlay performance affected by annealing heat treatment: II

    Science.gov (United States)

    Liu, Ying; Black, Iain

    2002-07-01

    Further analysis on how wafer distortion affecting the overlay performance during annealing treatment in GaAs wafer fabrication was conducted quantitatively using MONO-LITH software. The experimental results were decomposed as wafer translation, scaling at X and Y direction, rotation and orthogonality. The grid residual was used to describe non- correctable distortion of the wafers, which fits the equations given below: Residual equals Measured - Modeled, which is not a modeled component. The Vector Map displays distribution of error vectors over the wafer or field for various components or overall effect. Based on the component analysis that the misalignment caused by translation and scaling can be compensated by heat treatment if the wafer is placed at a favorable orientation. This can help mitigate the effects of substrate quality in manufactory.

  15. Processing moldable tasks on the grid: Late job binding with lightweight user-level overlay

    CERN Document Server

    Moscicki, J T; Sloot, P M A; Lamanna, M

    2011-01-01

    Independent observations and everyday user experience indicate that performance and reliability of large grid infrastructures may suffer from large and unpredictable variations. In this paper we study the impact of the job queuing time on processing of moldable tasks which are commonly found in large-scale production grids. We use the mean value and variance of makespan as the quality of service indicators. We develop a general task processing model to provide a quantitative comparison between two models: early and late job binding in a user-level overlay applied to the EGEE Grid infrastructure. We find that the late-binding model effectively defines a transformation of the distribution of makespan according to the Central Limit Theorem. As demonstrated by Monte Carlo simulations using real job traces, this transformation allows to substantially reduce the mean value and variance of makespan. For certain classes of applications task granularity may be adjusted such that a speedup of an order of magnitude or m...

  16. Key Management Schemes for Peer-to-Peer Multimedia Streaming Overlay Networks

    Science.gov (United States)

    Naranjo, J. A. M.; López-Ramos, J. A.; Casado, L. G.

    Key distribution for multimedia live streaming peer-to-peer overlay networks is a field still in its childhood stage. A scheme designed for networks of this kind must seek security and efficiency while keeping in mind the following restrictions: limited bandwidth, continuous playing, great audience size and clients churn. This paper introduces two novel schemes that allow a trade-off between security and efficiency by allowing to dynamically vary the number of levels used in the key hierarchy. These changes are motivated by great variations in audience size, and initiated by decision of the Key Server. Additionally, a comparative study of both is presented, focusing on security and audience size. Results show that larger key hierarchies can supply bigger audiences, but offer less security against statistical attacks. The opposite happens for shorter key hierarchies.

  17. Selection of network coding nodes for minimal playback delay in streaming overlays

    CERN Document Server

    Cleju, Nicolae; Frossard, Pascal

    2011-01-01

    availability in media streaming applications. However, it may also increase delay and computational complexity if it is not implemented efficiently. We address here the effective placement of nodes that implement randomized network coding in overlay networks, so that the goodput is kept high while the delay for decoding stays small in streaming applications. We first estimate the decoding delay at each client, which depends on the innovative rate in the network. This estimation permits to identify the nodes that have to perform coding for a reduced decoding delay. We then propose two iterative algorithms for selecting the nodes that should perform network coding. The first algorithm relies on the knowledge of the full network statistics. The second algorithm uses only local network statistics at each node. Simulation results show that large performance gains can be achieved with the selection of only a few network coding nodes. Moreover, the second algorithm performs very closely to the central estimation str...

  18. Interactive Overlays: A New Method for Generating Global Journal Maps from Web-of-Science Data

    CERN Document Server

    Leydesdorff, Loet

    2011-01-01

    Recent advances in methods and techniques enable us to develop an interactive overlay to the global map of science based on aggregated citation relations among the 9,162 journals contained in the Science Citation Index and Social Science Citation Index 2009 combined. The resulting mapping is provided by VOSViewer. We first discuss the pros and cons of the various options: cited versus citing, multidimensional scaling versus spring-embedded algorithms, VOSViewer versus Gephi, and the various clustering algorithms and similarity criteria. Our approach focuses on the positions of journals in the multidimensional space spanned by the aggregated journal-journal citations. A number of choices can be left to the user, but we provide default options reflecting our preferences. Some examples are also provided; for example, the potential of using this technique to assess the interdisciplinarity of organizations and/or document sets.

  19. MR cone-beam CT fusion image overlay for fluoroscopically guided percutaneous biopsies in pediatric patients.

    Science.gov (United States)

    Thakor, Avnesh S; Patel, Premal A; Gu, Richard; Rea, Vanessa; Amaral, Joao; Connolly, Bairbre L

    2016-03-01

    Lesions only visible on magnetic resonance (MR) imaging cannot easily be targeted for image-guided biopsy using ultrasound or X-rays but instead require MR guidance with MR-compatible needles and long procedure times (acquisition of multiple MR sequences). We developed an alternative method for performing these difficult biopsies in a standard interventional suite, by fusing MR with cone-beam CT images. The MR cone-beam CT fusion image is then used as an overlay to guide a biopsy needle to the target area under live fluoroscopic guidance. Advantages of this technique include (i) the ability for it to be performed in a conventional interventional suite, (ii) three-dimensional planning of the needle trajectory using cross-sectional imaging, (iii) real-time fluoroscopic guidance for needle trajectory correction and (iv) targeting within heterogeneous lesions based on MR signal characteristics to maximize the potential biopsy yield.

  20. Virtual and Dynamic Hierarchical Architecture: an overlay network topology for discovering grid services with high performance

    Institute of Scientific and Technical Information of China (English)

    黄理灿; 吴朝晖; 潘云鹤

    2004-01-01

    This paper presents an overlay network topology called Virtual and Dynamic Hierarchical Architecture (VDHA) for discovering Grid services with high performance. Service discovery based on VDHA has scalable, autonomous, efficient, reliable and quick responsive. We propose two service discovery algorithms. Full Search Query and Discovery Protocol (FSQDP) discovers the nodes that match the request message from all N nodes, which has time complexity O(logN), space complexity O(nvg) (nvg being node numbers of each virtual group), and message-cost O(N), and Domain-Specific Query and Discovery Protocol (DSQDP) searches nodes in only specific domains with time complexity O(nvg), space complexity O(nvg), and message-cost O(nvg). In this paper, we also describe VDHA, its formal definition, and Grid Group Management Protocol.

  1. Distributed Algorithms for Improving Search Efficiency in P2P Overlays

    Directory of Open Access Journals (Sweden)

    Chittaranjan Hota

    2012-04-01

    Full Text Available Peer-to-peer (P2P overlay is a distributed application architecture in which peers share their resources. Peers are equally privileged, equipotent participants in the application. Several algorithms for enhancing P2P file searching have been proposed in the literature. In this paper, we have proposed a unique approach of reducing the P2P search complexity and improving search efficiency by using distributed algorithms. In our approach a peer mounts other popular peer’s files and also replicates other popular files or critical files identified using a threshold value. Once a file is mounted, file access requests can be serviced by transparently retrieving the file and sending it to the requesting peer. Replication used in this work improves the file retrieval time by allowing parallel transfer. We have shown the performance analysis of our proposed approach which shows improvement in the search efficiency.

  2. An Efficient, Scalable and Robust P2P Overlay for Autonomic Communication

    Science.gov (United States)

    Li, Deng; Liu, Hui; Vasilakos, Athanasios

    The term Autonomic Communication (AC) refers to self-managing systems which are capable of supporting self-configuration, self-healing and self-optimization. However, information reflection and collection, lack of centralized control, non-cooperation and so on are just some of the challenges within AC systems. Since many self-* properties (e.g. selfconfiguration, self-optimization, self-healing, and self-protecting) are achieved by a group of autonomous entities that coordinate in a peer-to-peer (P2P) fashion, it has opened the door to migrating research techniques from P2P systems. P2P's meaning can be better understood with a set of key characteristics similar to AC: Decentralized organization, Self-organizing nature (i.e. adaptability), Resource sharing and aggregation, and Fault-tolerance. However, not all P2P systems are compatible with AC. Unstructured systems are designed more specifically than structured systems for the heterogeneous Internet environment, where the nodes' persistence and availability are not guaranteed. Motivated by the challenges in AC and based on comprehensive analysis of popular P2P applications, three correlative standards for evaluating the compatibility of a P2P system with AC are presented in this chapter. According to these standards, a novel Efficient, Scalable and Robust (ESR) P2P overlay is proposed. Differing from current structured and unstructured, or meshed and tree-like P2P overlay, the ESR is a whole new three dimensional structure to improve the efficiency of routing, while information exchanges take in immediate neighbors with local information to make the system scalable and fault-tolerant. Furthermore, rather than a complex game theory or incentive mechanism, asimple but effective punish mechanism has been presented based on a new ID structure which can guarantee the continuity of each node's record in order to discourage negative behavior on an autonomous environment as AC.

  3. Interactive overlays of journals and the measurement of interdisciplinarity on the basis of aggregated journal-journal citations

    NARCIS (Netherlands)

    Leydesdorff, L.; Rafols, I.; Chen, C.

    2013-01-01

    Using the option Analyze Results with the Web of Science, one can directly generate overlays onto global journal maps of science. The maps are based on the 10,000+ journals contained in the Journal Citation Reports (JCR) of the Science and Social Sciences Citation Indices (2011). The disciplinary di

  4. Journal maps, interactive overlays, and the measurement of interdisciplinarity on the basis of Scopus data (1996-2012)

    NARCIS (Netherlands)

    Leydesdorff, L.; de Moya-Anegón, F.; Guerrero-Bote, V.P.

    2015-01-01

    Using Scopus data, we construct a global map of science based on aggregated journal-journal citations from 1996-2012 (N of journals = 20,554). This base map enables users to overlay downloads from Scopus interactively. Using a single year (e.g., 2012), results can be compared with mappings based on

  5. Overlay accuracy on a flexible web with a roll printing process based on a roll-to-roll system.

    Science.gov (United States)

    Chang, Jaehyuk; Lee, Sunggun; Lee, Ki Beom; Lee, Seungjun; Cho, Young Tae; Seo, Jungwoo; Lee, Sukwon; Jo, Gugrae; Lee, Ki-yong; Kong, Hyang-Shik; Kwon, Sin

    2015-05-01

    For high-quality flexible devices from printing processes based on Roll-to-Roll (R2R) systems, overlay alignment during the patterning of each functional layer poses a major challenge. The reason is because flexible substrates have a relatively low stiffness compared with rigid substrates, and they are easily deformed during web handling in the R2R system. To achieve a high overlay accuracy for a flexible substrate, it is important not only to develop web handling modules (such as web guiding, tension control, winding, and unwinding) and a precise printing tool but also to control the synchronization of each unit in the total system. A R2R web handling system and reverse offset printing process were developed in this work, and an overlay between the 1st and 2nd layers of ±5μm on a 500 mm-wide film was achieved at a σ level of 2.4 and 2.8 (x and y directions, respectively) in a continuous R2R printing process. This paper presents the components and mechanisms used in reverse offset printing based on a R2R system and the printing results including positioning accuracy and overlay alignment accuracy.

  6. Aantonen van virussen in water: een vergelijking van de detectiegevoeligheid van de immunoperoxidase methode met de plaque overlay methode

    NARCIS (Netherlands)

    Theunissen JJH; Krebbers AHW; Medema GJ; MGB

    1996-01-01

    In dit rapport wordt een mogelijkheid beschreven om de gevoeligheid van de huidige virus detectiemethode, de plaque overlay, te verbeteren, wat zou leiden tot een betere inschatting van het virusgehalte in oppervlaktewater. De immunoperoxidase methode bleek, voor het kwantitatief aantonen van vi

  7. Maxillary and mandibular overlay removable partial dentures for restoration of worn teeth. A three-year follow-up.

    Science.gov (United States)

    Almog, Dov M; Ganddini, Mario R

    2006-01-01

    This clinical report describes the fabrication and a three-year follow-up of maxillary and mandibular cast overlay removable partial dentures for the restoration of severely worn dentition with accompanying loss of vertical dimension of occlusion. The frameworks supported porcelain veneers for esthetics, and metal occlusal surfaces for strength and durability.

  8. Field application of phased array ultrasonic testing for structural weld overlay on dissimilar welds of pressurizer nozzles

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jin Hoi; Kim, Yong Sik [Korea Hydro and Nuclear Power Company Ltd., Central Research Institute, Daejeon (Korea, Republic of)

    2015-08-15

    Weld overlay was first used in power plants in the US in the early 1980s as an interim method of repairing the welds of flawed piping joints. Weld overlaid piping joints in nuclear power plants must be examined periodically using ultrasonic examination technology. Portable phased array ultrasonic technology has recently become available. Currently, the application of preemptive weld overlays as a mitigation technique and/as a method to improve the examination surface condition for more complex configurations is becoming more common. These complex geometries may require several focused conventional transducers for adequate inspection of the overlay, the original weld, and the base material. Alternatively, Phased array ultrasonic probes can be used to generate several inspection angles simultaneously at various focal depths to provide better and faster coverage than that possible by conventional methods. Thus, this technology can increase the speed of examinations, save costs, and reduce radiation exposure. In this paper, we explain the general sequence of the inspection of weld overlay and the results of signal analysis for some PAUT (phased array ultrasonic testing) signals detected in on-site inspections.

  9. "Paraffin wax-overlay of pour plate", a method for the isolation and enumeration of purple non-sulfur bacteria.

    Science.gov (United States)

    Archana, A; Sasikala, Ch; Ramana, Ch V; Arunasri, K

    2004-12-01

    A modification of pour plate technique with an overlay of wax was used for isolation and enumeration of purple non-sulfur bacteria (PNSB) with equal efficiency as that of agar shake culture. The total count of PNSB ranged from 10(5)-10(8) CFU g dry soil(-1) and belonged to the genera of Rhodobacter, Rhodopseudomonas, Rhodocista and Rubrivivax.

  10. Evaluation of iron aluminide weld overlays for erosion - corrosion resistant boiler tube coatings in low NO{sub x} boilers

    Energy Technology Data Exchange (ETDEWEB)

    DuPont, J.N.; Banovic, S.W.; Marder, A.R. [Lehigh Univ., Bethlehem, PA (United States)

    1996-08-01

    Low NOx burners are being installed in many fossil fired power plants in order to comply with new Clean Air Regulations. Due to the operating characteristics of these burners, boiler tube sulfidation corrosion is often enhanced and premature tube failures can occur. Failures due to oxidation and solid particle erosion are also a concern. A program was initiated in early 1996 to evaluate the use of iron aluminide weld overlays for erosion/corrosion protection of boiler tubes in Low NOx boilers. Composite iron/aluminum wires will be used with the Gas Metal Arc Welding (GMAW) process to prepare overlays on boiler tubes steels with aluminum contents from 8 to 16wt%. The weldability of the composite wires will be evaluated as a function of chemical composition and welding parameters. The effect of overlay composition on corrosion (oxidation and sulfidation) and solid particle erosion will also be evaluated. The laboratory studies will be complemented by field exposures of both iron aluminide weld overlays and co-extruded tubing under actual boiler conditions.

  11. Overlays in Mobile P2P Networks%移动对等网络覆盖网

    Institute of Scientific and Technical Information of China (English)

    张国印; 李军

    2013-01-01

    The construction of overlays is a crucial problem in the research of mobile peer-to-peer networks.The architecture of overlays determines the robustness,security and performance of MP2P networks.The paper first introduces the concept of mobile P2P overlays,including the definition,significance of the construction of overlays and the classification of them.Next,three kinds of overlays,distributed unstructured,distributed structured and semi distributed (hybrid) network,are described.The application of overlays in MANET,VANET and WMN is especially introduced.Furthermore,the aforementioned overlays are analyzed and compared.Finally,the paper concludes and presents the future research directions.%在移动对等网络的研究工作中,覆盖网络的构造是一个十分关键的核心问题.覆盖网络体系结构决定了移动对等网络的健壮性、安全性和性能.首先提出移动对等覆盖网络的概念,给出了其定义、构建覆盖网的重要意义和覆盖网的分类.然后阐述了3类不同的覆盖网,即分布式非结构化网络、分布式结构化网络和半分布式(混合式)网络,其中特别论述了这些覆盖网在移动自组网、车辆自组网以及无线Mesh网络等方面的应用,并进行了分析和比较.最后,对整个移动对等覆盖网络研究工作进行了总结,并对下一步研究方向进行了展望.

  12. Spanish Round Robin test on water sensitivity test of bituminous mixtures; Ejercicio espanol interlaboratorios sobre el ensayo de sensibilidad al gua de mezclas bituminosas

    Energy Technology Data Exchange (ETDEWEB)

    Jimenez Saez, R.; Enrique Gabeiras, L.; Miranda Perez, L.; Valor Hernandez, F.

    2011-07-01

    The amendment of Article 542 and 543 on the hot asphalt mixtures included in the Spanish Technical specifications for Road Construction (PG-3), by Circular Order 24/2008, introduced a new series of modification to adapt Spanish regulations to European standards series EN 13108. Among the various amendments, new tests methods and design criteria are considered, as UNE-EN 12697-12 for assessing the water sensitivity on compacted specimens, which is mandatory for every kind of bituminous mixture. In this paper, firstly a comparison between the European method and the old Spanish method described in the NLT-162 is made, explaining the experimental conditions selected. The results of an interlaboratory study or Round Robin Test conducted in ten Spanish laboratories are subsequently described and analyzed, in order to allow each laboratory to assess its technical performance, and also to determine quantitatively the precision of the new method in terms of repeatability and reproducibility. (Author) 15 refs.

  13. Investigation of the weldability of iron-aluminum-chromium overlay coatings for corrosion protection in oxidizing/sulfidizing environments

    Science.gov (United States)

    Regina, Jonathan R.

    The current study investigated the effect of chromium additions on the hydrogen cracking susceptibility of Fe-Al weld overlay claddings containing chromium additions. It was found that the weldability of FeAlCr claddings was a function of both the aluminum and chromium concentrations of the weld coatings. Weld overlay compositions that were not susceptible to hydrogen cracking were identified and the underlying mechanism behind the hydrogen cracking phenomenon was investigated further. It was concluded that the cracking behavior of the FeAlCr welds depended strongly on the microstructure of the weld fusion zone. Although it was found that the cracking susceptibility was influenced by the presence of Fe-Al intermetallic phases (namely Fe3 Al and FeAl), the cracking behavior of FeAlCr weld overlay claddings also depended on the size and distribution of carbide and oxide particles present within the weld structure. These particles acted as hydrogen trapping sites, which are areas where free hydrogen segregates and can no longer contribute to the hydrogen embrittlement of the metal. It was determined that in practical applications of these FeAlCr weld overlay coatings, carbon should be present within these welds to reduce the amount of hydrogen available for hydrogen cracking. Based on the weldability results of the FeAlCr weld claddings, coating compositions that were able to be deposited crack-free were used for long-term corrosion testing in a simulated low NOx environment. These alloys were compared to a Ni-based superalloy (622), which is commonly utilized as boiler tube coatings in power plant furnaces for corrosion protection. It was found that the FeAlCr alloys demonstrated superior corrosion resistance when compared to the Ni-based superalloy. Due to the excellent long-term corrosion behavior of FeAlCr weld overlays that were immune to hydrogen cracking, it was concluded that select FeAlCr weld overlay compositions would make excellent corrosion resistant

  14. Structural studies of molecular and metallic overlayers using angle- resolved photoemission extended fine structure

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Z.

    1992-10-01

    Angle-resolved photoemission extended fine structure (ARPEFS) was used to study molecular and metallic overlayers on metal surfaces through analysis of p2mg(2[times]1)CO/Ni(110) and the p(2[times]2)K/Ni(111) adsorption. For the dense p2mg(2[times]1)CO/Ni(110) surface layer, photoemission intensities from C 1s level were measured in three directions at photoelectron kinetic energies 60-400 eV. Using multiple-scattering spherical-wave (MSSW) modeling, it was found that CO molecules are adsorbed on short-bridge sites, with adjacent CO along the [110] direction displaced alternatively in opposite directions towards the [001] azimuths to form a zigzag chain geometry. The tilt angle is 16[plus minus]2[degree] from the surface normal for the direction linking the C atom and the center of the Ni bridge. The carbon C-Ni interatomic distance was determined to be 1.94[plus minus]0.02[Angstrom]. The first- to second-layer spacing of Ni is 1.27[plus minus]0.04[Angstrom], up from 1.10[Angstrom] for the clean Ni(110) surface, but close to the 1.25[Angstrom] Ni interlayer spacing in the bulk. The C-O bond length and tilt angle were varied within small ranges (1.10--1.20[Angstrom] and 15--23[degrees]) in our MSSW simulations. Best agreement between experiment and simulations was achieved at 1.16[Angstrom] and 19[degrees]. This yields an O-O distance of 2.95[Angstrom] for the two nearest CO molecules, (van der Waals' radius [approximately] 1.5 [Angstrom] for oxygen). Two different partial-wave phase-shifts were used in MSSW, and structural results from both are in very good agreement. For the p(2[times]2)K/Ni(111) overlayer, ARPEFS [chi](k) curves from K 1s level measured along [111] and [771] at 130K showed that the K atoms are preferentially adsorbed on the atop sites, in agreement with a LEED study of the same system.

  15. Structural studies of molecular and metallic overlayers using angle- resolved photoemission extended fine structure

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Z.

    1992-10-01

    Angle-resolved photoemission extended fine structure (ARPEFS) was used to study molecular and metallic overlayers on metal surfaces through analysis of p2mg(2{times}1)CO/Ni(110) and the p(2{times}2)K/Ni(111) adsorption. For the dense p2mg(2{times}1)CO/Ni(110) surface layer, photoemission intensities from C 1s level were measured in three directions at photoelectron kinetic energies 60-400 eV. Using multiple-scattering spherical-wave (MSSW) modeling, it was found that CO molecules are adsorbed on short-bridge sites, with adjacent CO along the [110] direction displaced alternatively in opposite directions towards the [001] azimuths to form a zigzag chain geometry. The tilt angle is 16{plus_minus}2{degree} from the surface normal for the direction linking the C atom and the center of the Ni bridge. The carbon C-Ni interatomic distance was determined to be 1.94{plus_minus}0.02{Angstrom}. The first- to second-layer spacing of Ni is 1.27{plus_minus}0.04{Angstrom}, up from 1.10{Angstrom} for the clean Ni(110) surface, but close to the 1.25{Angstrom} Ni interlayer spacing in the bulk. The C-O bond length and tilt angle were varied within small ranges (1.10--1.20{Angstrom} and 15--23{degrees}) in our MSSW simulations. Best agreement between experiment and simulations was achieved at 1.16{Angstrom} and 19{degrees}. This yields an O-O distance of 2.95{Angstrom} for the two nearest CO molecules, (van der Waals` radius {approximately} 1.5 {Angstrom} for oxygen). Two different partial-wave phase-shifts were used in MSSW, and structural results from both are in very good agreement. For the p(2{times}2)K/Ni(111) overlayer, ARPEFS {chi}(k) curves from K 1s level measured along [111] and [771] at 130K showed that the K atoms are preferentially adsorbed on the atop sites, in agreement with a LEED study of the same system.

  16. Equipment stainless steel entire versus steels bimetallics clad or overlay; Utilizacao de equipamentos de processo construidos em aco inoxidavel integral versus acos bimetalicos cladeado ou 'overlay'

    Energy Technology Data Exchange (ETDEWEB)

    Batista, Itamar da Silva; Lima, Jadival Carneiro de; Leal, Murilo Fonseca; Cardoso, Amauri dos Santos; Jorjan, Roberto [PETROBRAS S.A., Sao Francisco do Conde, BA (Brazil). Refinaria Landulfo Alves Mataripen (RLAM)

    2008-07-01

    This study does not recommend the use of a pressure vessel made of integral stainless steel, due to the failure mechanisms under stress corrosion assisted by chlorides or polythionic acid. Are presented case studies of literature and analysis of reports of proceedings of RLAM reactors, showing that the materials produced by bimetallic clad overlay or are more appropriate, in terms of integrity, for use in equipment that the internal environment requires austenitic stainless steel specification.

  17. Optimal overlayer inspired by Photuris firefly improves light-extraction efficiency of existing light-emitting diodes.

    Science.gov (United States)

    Bay, Annick; André, Nicolas; Sarrazin, Michaël; Belarouci, Ali; Aimez, Vincent; Francis, Laurent A; Vigneron, Jean Pol

    2013-01-14

    In this paper the design, fabrication and characterization of a bioinspired overlayer deposited on a GaN LED is described. The purpose of this overlayer is to improve light extraction into air from the diode's high refractive-index active material. The layer design is inspired by the microstructure found in the firefly Photuris sp. The actual dimensions and material composition have been optimized to take into account the high refractive index of the GaN diode stack. This two-dimensional pattern contrasts other designs by its unusual profile, its larger dimensions and the fact that it can be tailored to an existing diode design rather than requiring a complete redesign of the diode geometry. The gain of light extraction reaches values up to 55% with respect to the reference unprocessed LED.

  18. Self-Adapting Routing Overlay Network for Frequently Changing Application Traffic in Content-Based Publish/Subscribe System

    Directory of Open Access Journals (Sweden)

    Meng Chi

    2014-01-01

    Full Text Available In the large-scale distributed simulation area, the topology of the overlay network cannot always rapidly adapt to frequently changing application traffic to reduce the overall traffic cost. In this paper, we propose a self-adapting routing strategy for frequently changing application traffic in content-based publish/subscribe system. The strategy firstly trains the traffic information and then uses this training information to predict the application traffic in the future. Finally, the strategy reconfigures the topology of the overlay network based on this predicting information to reduce the overall traffic cost. A predicting path is also introduced in this paper to reduce the reconfiguration numbers in the process of the reconfigurations. Compared to other strategies, the experimental results show that the strategy proposed in this paper could reduce the overall traffic cost of the publish/subscribe system in less reconfigurations.

  19. Pavement structure mechanics response of flexible on semi-flexible overlay that based on the old cement concrete pavement damage

    Directory of Open Access Journals (Sweden)

    Jiang Ruinan

    2015-01-01

    Full Text Available The old cement pavement damage status directly affect the design of the paving renovation. Based on the state of the old road investigation, combined with the research data at home and abroad, use the control index that average deflection, deflection value and CBR value to determine the reasonable time to overlay. Draw up the typical pavement structure according to the principle of combination of old cement pavement overlay structure design, and calculated that the tensile stress and shear stress in asphalt layer ,semi-flexible layer and the tensile in the old cement pavement adopting BISA3.0 statics finite element analysis model when modulus in the old road was diminishing. Use the computed result to analyses the influence of old road damage condition the influence of pavement structure.

  20. Optical resonance analysis of reflected long period fiber gratings with metal film overlay

    Science.gov (United States)

    Zhang, Guiju; Cao, Bing; Wang, Chinua; Zhao, Minfu

    2008-11-01

    We present the experimental results of a novel single-ended reflecting surface plasma resonance (SPR) based long period fiber grating (LPFG) sensor. A long period fiber grating sensing device is properly designed and fabricated with a pulsed CO2 laser writing system. Different nm-thick thin metal films are deposited on the fiber cladding and the fiber end facet for the excitation of surface plasma waves (SPWs) and the reflection of the transmission spectrum of the LPFG with doubled interaction between metal-dielectric interfaces of the fiber to enhance the SPW of the all-fiber SPR-LPFG sensing system. Different thin metal films with different thicknesses are investigated. The effect of the excited SPW transmission along the fiber cladding-metal interface with silver and aluminum films is observed. It is found that different thicknesses of the metal overlay show different resonant behaviors in terms of resonance peak situation, bandwidth and energy loss. Within a certain range, thinner metal film shows narrower bandwidth and deeper peak loss.

  1. EVM as generic QoS trigger for heterogeneous wieless overlay network

    CERN Document Server

    Kumar, Rajender; 10.5121/ijwmn.2010.2315

    2010-01-01

    Fourth Generation (4G) Wireless System will integrate heterogeneous wireless overlay systems i.e. interworking of WLAN/ GSM/ CDMA/ WiMAX/ LTE/ etc with guaranteed Quality of Service (QoS) and Experience (QoE).QoS(E) vary from network to network and is application sensitive. User needs an optimal mobility solution while roaming in Overlaid wireless environment i.e. user could seamlessly transfer his session/ call to a best available network bearing guaranteed Quality of Experience. And If this Seamless transfer of session is executed between two networks having different access standards then it is called Vertical Handover (VHO). Contemporary VHO decision algorithms are based on generic QoS metrics viz. SNR, bandwidth, jitter, BER and delay. In this paper, Error Vector Magnitude (EVM) is proposed to be a generic QoS trigger for VHO execution. EVM is defined as the deviation of inphase/ quadrature (I/Q) values from ideal signal states and thus provides a measure of signal quality. In 4G Interoperable environmen...

  2. Severe headache as a presenting complaint in sigmoid sinus thrombosis complicated by functional overlay.

    Science.gov (United States)

    Chaudhary, Pradhyuman; Banwari, Girish; Parikh, Nimesh; Gandhi, Hitendra

    2015-01-01

    An otherwise serious and potentially fatal organic condition may present with a co-existing strong functional component. We encountered a female patient who presented with bouts of severe headache over the occipital region, associated with blurring of vision. Initially, non-contrast computed tomography (CT) scan (Brain) showed normal study, and she was deemed as having functional symptoms. Later, magnetic resonance imaging (MRI) (Brain) showed filling defect in right sigmoid sinus and magnetic resonance (MR) venography confirmed right sigmoid sinus thrombosis. On adequate anticoagulation, she did not improve and still had bouts of severe headache, although no longer associated with impaired vision. The treating neurophysician concluded that symptoms could no longer be accounted for by the organic condition. Overt and covert psychosocial stressors were found to be present in a detailed psychological exploration. Psychological intervention effectively controlled the headache. Thus, functional overlay can complicate the clinical picture in a severe organic condition and may require active psychiatric intervention over and above medical treatment.

  3. Optimization of liquid overlay technique to formulate heterogenic 3D co-cultures models.

    Science.gov (United States)

    Costa, Elisabete C; Gaspar, Vítor M; Coutinho, Paula; Correia, Ilídio J

    2014-08-01

    Three-dimensional (3D) cell culture models of solid tumors are currently having a tremendous impact in the in vitro screening of candidate anti-tumoral therapies. These 3D models provide more reliable results than those provided by standard 2D in vitro cell cultures. However, 3D manufacturing techniques need to be further optimized in order to increase the robustness of these models and provide data that can be properly correlated with the in vivo situation. Therefore, in the present study the parameters used for producing multicellular tumor spheroids (MCTS) by liquid overlay technique (LOT) were optimized in order to produce heterogeneous cellular agglomerates comprised of cancer cells and stromal cells, during long periods. Spheroids were produced under highly controlled conditions, namely: (i) agarose coatings; (ii) horizontal stirring, and (iii) a known initial cell number. The simultaneous optimization of these parameters promoted the assembly of 3D characteristic cellular organization similar to that found in the in vivo solid tumors. Such improvements in the LOT technique promoted the assembly of highly reproducible, individual 3D spheroids, with a low cost of production and that can be used for future in vitro drug screening assays.

  4. Conventional versus implant-retained overlay dentures: a pilot study of masseter and anterior temporalis electromyography.

    Science.gov (United States)

    Dakhilalian, Mansour; Rismanchian, Mansour; Fazel, Akbar; Basiri, Keyvan; Azadeh, Hamid; Mahmoodi, Maryam; Fayazi, Sara; Sadr-Eshkvari, Pooyan

    2014-08-01

    Implant-supported overlay dentures (ISODs) have been widely accepted among patients using conventional removable complete dentures (CRCDs). The present study aimed to comparatively study conventional and ISODs in terms of function and coordination of masticatory muscles using electromyograms. Included were 10 patients with ISODs (each with 2 implants in the intercanine area). The mean wave range (MWR) and frequency (MWF) of masseter and temporalis were recorded with (ISOD) and without (CRCD) ball attachments while maximum clenching on cotton rolls (cotton roll clenching), maximum intercuspal clenching (clenching), and unilateral gum chewing (chewing) using electromyography. Data were analyzed in SPAW using t-paired for matched groups and independent-sample t tests for unmatched ones. The MWF differences were not statistically significant with or without attachments (P > .05). Without attachments in place, the MWF of both masseter and temporalis muscles significantly decreased when patients clenched on cotton rolls (P = .01 and .02, respectively) and when chewing unilaterally (both P = .01). With attachments present, the right and left temporalis muscles did not show identical mean wave ranges while chewing (P = .01). Without attachments, this disharmony was seen in the left and right masseter muscles (P = .03). The MWR of masseter was higher in men while chewing with attachments (P = .02). Without attachments, the MWR of temporalis was higher in women while cotton roll clenching (P = .03) and chewing (P = .02). These findings are seemingly in favor of improved masticatory function and coordination in edentulous patients with the application of ISODs.

  5. Structured P2P overlay of mobile brokers for realizing publish/subscribe communication in VANET.

    Science.gov (United States)

    Pandey, Tulika; Garg, Deepak; Gore, Manoj Madhava

    2014-01-01

    Publish/subscribe communication paradigm provides asynchrony and decoupling, making it an elegant alternative for designing applications in distributed and dynamic environment such as vehicular ad hoc networks (VANETs). In this paradigm, the broker is the most important component that decouples other two components, namely, publisher and subscriber. Previous research efforts have either utilized the deployment of distributed brokers on stationary road side info-stations or have assigned the role of broker to any moving vehicle on ad hoc basis. In one approach, lots of preinstalled infrastructures are needed whereas, in another, the quality of service is not guaranteed due to unpredictable moving and stopping patterns of vehicles. In this paper, we present the architecture of distributed mobile brokers which are dynamically reconfigurable in the form of structured P2P overlay and act as rendezvous points for matching publications and subscriptions. We have taken city buses in urban settings to act as mobile brokers whereas other vehicles are considered to be in role of publishers and subscribers. These mobile brokers also assist in locating a vehicle for successful and timely transfer of notifications. We have performed an extensive simulation study to compare our approach with previously proposed approaches. Simulation results establish the applicability of our approach.

  6. Curing units' ability to cure restorative composites and dual-cured composite cements under composite overlay.

    Science.gov (United States)

    Park, Sung-Ho; Kim, Su-Sun; Cho, Yong-Sik; Lee, Chang-Kyu; Noh, Byng-Duk

    2004-01-01

    This study compared the efficacy of using conventional low-power density QTH (LQTH) units, high-power density QTH (HQTH) units, argon (Ar) laser and Plasma arc curing (PAC) units for curing dual-cured resin cements and restorative resin composites under a pre-cured resin composite overlay. The microhardness of the two types of restorative resins (Z100 and Tetric Ceram) and a dual-cured resin cement (Variolink II) were measured after they were light cured for 60 seconds in a 2 mm Teflon mold. The recorded microhardness was determined to be the optimum microhard-ness (OM). Either one of the two types of restorative resins (Z100, Tetric Ceram) or the dual cured resin cement (Variolink II) were placed under a 1.5-mm thick and 8 mm diameter pre-cured Targis (Vivadent/Ivoclar AG, Schaan, Liechtenstein) overlay. The specimens that were prepared for each material were divided into four groups depending upon the curing units used (HQTH, PAC, Laser or LQTH) and were further subdi-vided into subgroups according to light curing time. The curing times used were 30, 60, 90 and 120 seconds for HQTH; 12, 24, 36 and 48 seconds for the PAC unit; 15, 30, 45 and 60 for the Laser and 60, 120 or 180 seconds for the LQTH unit. Fifteen specimens were assigned to each sub- group. The microhardness of the upper and and lower composite surfaces under the Targis overlay were measured using an Optidur Vickers hardness-measuring instrument (Göttfert Feinwerktechnik GmbH, Buchen, Germany). In each material, for each group, a three-way ANOVA with Tukey was used at the 0.05 level of significance to compare the microhardnesses of the upper and lower composite surfaces and the previously measured OM of the material. From the OM of each material, 80% OM was calculated and the time required for the microhardness of the upper and lower surface of the specimen to reach 100% and 80% of OM was determined. In Z100 and Tetric Ceram, when the composites were light cured for 120 seconds using the HQTH lamp

  7. Determining the Co-Rotation Radius of Nearby Spiral Galaxies Using Spiral Arm Overlays

    Science.gov (United States)

    Shameer Abdeen, Mohamed; Kennefick, Daniel; Kennefick, Julia D.; Pour Imani, Hamed; Shields, Douglas W.; Eufrasio, Rafael; Berlanga Medina, Jazmin; Monson, Erik

    2017-01-01

    Density wave theory, originally proposed by C.C. Lin and Frank Shu (Lin & Shu 1964), views the spiral arm structures in spiral galaxies as density waves that propagates through the galactic disk. Resonances within orbits create standing wave patterns of density waves that we observe as spiral arms. The theory predicts the existence of a radius known as the co-rotation radius in which the spiral arm pattern speed matches the velocities of the stars within the disk. We introduce a novel way of determining the co-rotation radius, based on an image overlaying technique, which involves tracing the arms of spiral galaxies on images observed from different wavelengths. For the purpose of this study, 12 nearby galaxies were analyzed from four different wavelengths using pitch angle measurements from a previous study (Hamed et al. 2016). We used optical wavelength images (B-Band,440 nm), two infrared wavelength (Infrared; 3.6 µm and 8 µm) Spitzer Space Telescope images and ultraviolet images from GALEX. The results were verified by checking against results compiled from the literature.

  8. First principles analysis of hydrogen chemisorption on Pd-Re alloyed overlayers and alloyed surfaces

    DEFF Research Database (Denmark)

    Pallassana, Venkataraman; Neurock, Matthew; Hansen, Lars Bruno;

    2000-01-01

    Gradient corrected periodic density functional theory (DFT-GGA) slab calculations were used to examine the chemisorption of atomic hydrogen on various Pd-Re alloyed overlayers and uniformly alloyed surfaces. Adsorption was examined at 33% surface coverage, where atomic hydrogen preferred the three......-fold fcc sites. The binding energy of atomic hydrogen is observed to vary by as much as 0.7 eV due to Pd-Re interactions. The computed adsorption energies were found to be between -2.35 eV [for monolayer Pd-on-Re, i.e., Pd-ML/Re(0001)] and -3.05 eV [for Pd-33 Re-66/Pd(111)]. A d-band weighting scheme...... was developed to extend the Hammer-Norskov surface reactivity model [Surf. Sci. 343, 211 (1995)] to the analysis of bimetallic Pd-Re alloyed systems. The hydrogen chemisorption energies are correlated linearly to the surface d-band center, which is weighted appropriately by the d-band coupling matrix elements...

  9. Error analysis of overlay compensation methodologies and proposed functional tolerances for EUV photomask flatness

    Science.gov (United States)

    Ballman, Katherine; Lee, Christopher; Dunn, Thomas; Bean, Alexander

    2016-05-01

    Due to the impact on image placement and overlay errors inherent in all reflective lithography systems, EUV reticles will need to adhere to flatness specifications below 10nm for 2018 production. These single value metrics are near impossible to meet using current tooling infrastructure (current state of the art reticles report P-V flatness ~60nm). In order to focus innovation on areas which lack capability for flatness compensation or correction, this paper redefines flatness metrics as being "correctable" vs. "non-correctable" based on the surface topography's contributions to the final IP budget at wafer, as well as whether data driven corrections (write compensation or at scanner) are available for the reticle's specific shape. To better understand and define the limitations of write compensation and scanner corrections, an error budget for processes contributing to these two methods is presented. Photomask flatness measurement tools are now targeting 6σ reproducibility <1nm (previous 3σ reproducibility ~3nm) in order to drive down error contributions and provide more accurate data for correction techniques. Taking advantage of the high order measurement capabilities of improved metrology tooling, as well as computational capabilities which enable fast measurements and analysis of sophisticated shapes, we propose a methodology for the industry to create functional tolerances focused on the flatness errors that are not correctable with compensation.

  10. Overlay Cognitive Radios With Channel-Aware Adaptive Link Selection and Buffer-Aided Relaying

    KAUST Repository

    Shaqfeh, Mohammad

    2015-08-01

    The aim of this work is to maximize the long-term average achievable rate region of a primary and a secondary source-destination pairs operating in an overlay setup over block-fading channels. To achieve this objective, we propose an opportunistic strategy to grant channel access to the primary and secondary sources based on the channel conditions in order to exploit the available multiple-link diversity gains in the system. The secondary source has causal knowledge of the primary messages and it acts as a relay of the primary source in return for getting access to the channel. To maximize the gains of relaying, the relay and destination are equipped with buffers to enable the use of channel-aware adaptive link selection. We propose and optimize different link selection policies and characterize their expected achievable rates. Also, we provide several numerical results to demonstrate the evident mutual benefits of buffer-aided cooperation and adaptive link selection to the primary and the secondary source-destination pairs. © 1972-2012 IEEE.

  11. Peer-to-Peer Overlay in Mobile Ad-hoc Networks

    Science.gov (United States)

    Castro, Marcel C.; Kassler, Andreas J.; Chiasserini, Carla-Fabiana; Casetti, Claudio; Korpeoglu, Ibrahim

    Wireless multi-hop networks such as mobile ad-hoc (MANET) or wireless mesh networks (WMN) have attracted big research efforts during the last years as they have huge potential in several areas such as military communications, fast infrastructure replacement during emergency operations, extension of hotspots or as an alternative communication system. Due to various reasons, such as characteristics of wireless links, multi-hop forwarding operation, and mobility of nodes, performance of traditional peer-to-peer applications is rather low in such networks. In this book chapter, we provide a comprehensive and in-depth survey on recent research on various approaches to provide peer-to-peer services in wireless multi-hop networks. The causes and problems for low performance of traditional approaches are discussed. Various representative alternative approaches to couple interactions between the peer-to-peer overlay and the network layer are examined and compared. Some open questions are discussed to stimulate further research in this area.

  12. Carbon nanotube synthesis from propane decomposition on a pre-treated Ni overlayer

    Indian Academy of Sciences (India)

    J Sengupta; S K Panda; C Jacob

    2009-04-01

    Growth of carbon nanotubes (CNTs) was performed by atmospheric pressure chemical vapour deposition (APCVD) of propane on Si(111) with a pre-treated Ni overlayer acting as a catalyst. Prior to the growth of CNTs, a thin film of Ni was deposited on Si(111) substrate by evaporation and heat treated at 900°C. The growth of nanotubes was carried out at 850°C using propane as a source of carbon. Distribution of the catalyst particles over the Si substrate was analysed before and after heat treatment by atomic force microscopy (AFM). The X-ray diffraction (XRD) pattern of the grown material revealed that they are graphitic in nature. Field emission scanning electron microscopy (FESEM) was used to investigate the growth process and it was found that a catalytic particle was always situated at the tip of the tube thus implying a tip growth mechanism. Evidence for the presence of radial breathing mode from multi-wall nanotubes (MWNTs) in the grown sample was obtained from micro-Raman analysis. Finally, high-resolution transmission electron microscopic (HRTEM) analysis confirmed that the graphene layers of the CNTs are well ordered with typical 0.34 nm spacing.

  13. Software for MR image overlay guided needle insertions: the clinical translation process

    Science.gov (United States)

    Ungi, Tamas; U-Thainual, Paweena; Fritz, Jan; Iordachita, Iulian I.; Flammang, Aaron J.; Carrino, John A.; Fichtinger, Gabor

    2013-03-01

    PURPOSE: Needle guidance software using augmented reality image overlay was translated from the experimental phase to support preclinical and clinical studies. Major functional and structural changes were needed to meet clinical requirements. We present the process applied to fulfill these requirements, and selected features that may be applied in the translational phase of other image-guided surgical navigation systems. METHODS: We used an agile software development process for rapid adaptation to unforeseen clinical requests. The process is based on iterations of operating room test sessions, feedback discussions, and software development sprints. The open-source application framework of 3D Slicer and the NA-MIC kit provided sufficient flexibility and stable software foundations for this work. RESULTS: All requirements were addressed in a process with 19 operating room test iterations. Most features developed in this phase were related to workflow simplification and operator feedback. CONCLUSION: Efficient and affordable modifications were facilitated by an open source application framework and frequent clinical feedback sessions. Results of cadaver experiments show that software requirements were successfully solved after a limited number of operating room tests.

  14. Theoretical simulations of atomic and polyatomic bombardment of an organic overlayer on a metallic substrate

    CERN Document Server

    Krantzman, K D; Delcorte, A; Garrison, B J

    2003-01-01

    Our previous molecular dynamics simulations on initial test systems have laid the foundation for understanding some of the effects of polyatomic bombardment. In this paper, we describe simulations of the bombardment of a more realistic model system, an overlayer of sec-butyl-terminated polystyrene tetramers on a Ag left brace 1 1 1 right brace substrate. We have used this model system to study the bombardment with Xe and SF sub 5 projectiles at kinetic energies ranging from 0.50 to 5.0 keV. SF sub 5 sputters more molecules than Xe, but a higher percentage of these are damaged rather than ejected intact when the bombarding energy is greater than 0.50 keV. Therefore, at energies comparable to experimental values, the efficiency, measured as the yield-to-damage ratio, is greater with Xe than SF sub 5. Stable and intact molecules are generally produced by upward moving substrate atoms, while fragments are produced by the upward and lateral motion of reflected projectile atoms and fragments from the target molecul...

  15. Structured P2P Overlay of Mobile Brokers for Realizing Publish/Subscribe Communication in VANET

    Science.gov (United States)

    Pandey, Tulika; Garg, Deepak; Gore, Manoj Madhava

    2014-01-01

    Publish/subscribe communication paradigm provides asynchrony and decoupling, making it an elegant alternative for designing applications in distributed and dynamic environment such as vehicular ad hoc networks (VANETs). In this paradigm, the broker is the most important component that decouples other two components, namely, publisher and subscriber. Previous research efforts have either utilized the deployment of distributed brokers on stationary road side info-stations or have assigned the role of broker to any moving vehicle on ad hoc basis. In one approach, lots of preinstalled infrastructures are needed whereas, in another, the quality of service is not guaranteed due to unpredictable moving and stopping patterns of vehicles. In this paper, we present the architecture of distributed mobile brokers which are dynamically reconfigurable in the form of structured P2P overlay and act as rendezvous points for matching publications and subscriptions. We have taken city buses in urban settings to act as mobile brokers whereas other vehicles are considered to be in role of publishers and subscribers. These mobile brokers also assist in locating a vehicle for successful and timely transfer of notifications. We have performed an extensive simulation study to compare our approach with previously proposed approaches. Simulation results establish the applicability of our approach. PMID:24523629

  16. SiMPSON: Efficient Similarity Search in Metric Spaces over P2P Structured Overlay Networks

    Science.gov (United States)

    Vu, Quang Hieu; Lupu, Mihai; Wu, Sai

    Similarity search in metric spaces over centralized systems has been significantly studied in the database research community. However, not so much work has been done in the context of P2P networks. This paper introduces SiMPSON: a P2P system supporting similarity search in metric spaces. The aim is to answer queries faster and using less resources than existing systems. For this, each peer first clusters its own data using any off-the-shelf clustering algorithms. Then, the resulting clusters are mapped to one-dimensional values. Finally, these one-dimensional values are indexed into a structured P2P overlay. Our method slightly increases the indexing overhead, but allows us to greatly reduce the number of peers and messages involved in query processing: we trade a small amount of overhead in the data publishing process for a substantial reduction of costs in the querying phase. Based on this architecture, we propose algorithms for processing range and kNN queries. Extensive experimental results validate the claims of efficiency and effectiveness of SiMPSON.

  17. Structured P2P Overlay of Mobile Brokers for Realizing Publish/Subscribe Communication in VANET

    Directory of Open Access Journals (Sweden)

    Tulika Pandey

    2014-01-01

    Full Text Available Publish/subscribe communication paradigm provides asynchrony and decoupling, making it an elegant alternative for designing applications in distributed and dynamic environment such as vehicular ad hoc networks (VANETs. In this paradigm, the broker is the most important component that decouples other two components, namely, publisher and subscriber. Previous research efforts have either utilized the deployment of distributed brokers on stationary road side info-stations or have assigned the role of broker to any moving vehicle on ad hoc basis. In one approach, lots of preinstalled infrastructures are needed whereas, in another, the quality of service is not guaranteed due to unpredictable moving and stopping patterns of vehicles. In this paper, we present the architecture of distributed mobile brokers which are dynamically reconfigurable in the form of structured P2P overlay and act as rendezvous points for matching publications and subscriptions. We have taken city buses in urban settings to act as mobile brokers whereas other vehicles are considered to be in role of publishers and subscribers. These mobile brokers also assist in locating a vehicle for successful and timely transfer of notifications. We have performed an extensive simulation study to compare our approach with previously proposed approaches. Simulation results establish the applicability of our approach.

  18. Efficient content distribution for peer-to-peer overlays on mobile ad hoc networks

    Directory of Open Access Journals (Sweden)

    Afzal Mawji

    2011-07-01

    Full Text Available Peer-to-peer (P2P networks existing on a MANET are a natural evolution since both are decentralized and have dynamic topologies. As MANETs grow in use due to the increasing popularity of wireless mesh and 4G networks, it is expected that P2P applications will remain as a popular means of obtaining files. Network coding has been shown as an efficient means of sharing large files in a P2P network. With network coding, all file blocks have the same relative importance. This paper presents an efficient content distribution scheme that uses network coding to share large files in a P2P overlay running on a MANET. Peers request file blocks from multiple server nodes and servers multicast blocks to multiple receivers, providing efficient multipoint-to-multipoint communication. Simulation results show that compared to other common download techniques, the proposed scheme performs very well, having lower download time and energy consumption. Also, more peers participate in uploading the file, resulting in greater fairness.

  19. BulkTree: an overlay network architecture for live media streaming

    Institute of Scientific and Technical Information of China (English)

    GONG An; DING Gui-guang; DAI Qiong-hai; LIN Chuang

    2006-01-01

    Peer-to-peer (P2P) systems are now very popular. Current P2P systems are broadly of two kinds, structured and unstructured. The tree structured P2P systems used technologies such as distributed hash tables (DHT) and hierarchical clustering can search the required target quickly, however, in a tree, the internal node has a higher load and its leave or crash often causes a large population of its offspring's problems, so that in the highly dynamic Internet environment the tree structure may still suffer frequent breaks. On the other hand, most widely used unstructured P2P networks rely on central directory servers or massive message flooding, clearly not scalable. So, we consider both of the above systems' advantages and disadvantages and realize that in the P2P systems one node may fail easily, but that when a number of nodes organized as a set, which we call "super node", the set is robust. Super nodes can be created and updated aware of topology-aware, and used with simple protocol such as flooding or "servers" to exchange information. Furthermore the entire robust super node can be organized into exquisite tree structure. By using this overlay network architecture, P2P systems are robust, efficient, scalable and secure. The simulation results demonstrated that our architecture greatly reduces the alteration time of the structure while decreasing the average delay time, compared to the common tree structure.

  20. Wafer-based aberration metrology for lithographic systems using overlay measurements on targets imaged from phase-shift gratings.

    Science.gov (United States)

    van Haver, Sven; Coene, Wim M J; D'havé, Koen; Geypen, Niels; van Adrichem, Paul; de Winter, Laurens; Janssen, Augustus J E M; Cheng, Shaunee

    2014-04-20

    In this paper, a new methodology is presented to derive the aberration state of a lithographic projection system from wafer metrology data. For this purpose, new types of phase-shift gratings (PSGs) are introduced, with special features that give rise to a simple linear relation between the PSG image displacement and the phase aberration function of the imaging system. By using the PSGs as the top grating in a diffraction-based overlay stack, their displacement can be measured as an overlay error using a standard wafer metrology tool. In this way, the overlay error can be used as a measurand based on which the phase aberration function in the exit pupil of the lithographic system can be reconstructed. In practice, the overlay error is measured for a set of different PSG targets, after which this information serves as input to a least-squares optimization problem that, upon solving, provides estimates for the Zernike coefficients describing the aberration state of the lithographic system. In addition to a detailed method description, this paper also deals with the additional complications that arise when the method is implemented experimentally and this leads to a number of model refinements and a required calibration step. Finally, the overall performance of the method is assessed through a number of experiments in which the aberration state of the lithographic system is intentionally detuned and subsequently estimated by the new method. These experiments show a remarkably good agreement, with an error smaller than 5  mλ, among the requested aberrations, the aberrations measured by the on-tool aberration sensor, and the results of the new wafer-based method.

  1. The Effects of Carbide Characteristics on the Performance of Tungsten Carbide-Based Composite Overlays, Deposited by Plasma-Transferred Arc Welding

    Science.gov (United States)

    Fisher, G.; Wolfe, T.; Meszaros, K.

    2013-06-01

    In Alberta, there are huge quantities of ore processed to remove bitumen from oil sands deposits. The scale of production generates very aggressive tribocorrosive conditions during the mining, extraction, and upgrading processes. It is common to apply tungsten carbide-based composite overlays to improve the reliability and extend service lives of equipment and components. The performance of the applied overlays is largely dependent on the selection of the carbide type and the wear environment. This paper will evaluate overlays containing macrocrystalline, angular eutectic, and spherical eutectic tungsten carbides and discuss the performance of the overlays with a focus on carbide properties and the interactions between the service conditions and the composite material. This discussion will demonstrate how effective selection of protective materials can improve the reliability of oil sands equipment.

  2. Assessment of Weld Overlays for Mitigating Primary Water Stress Corrosion Cracking at Nickel Alloy Butt Welds in Piping Systems Approved for Leak-Before-Break

    Energy Technology Data Exchange (ETDEWEB)

    Sullivan, Edward J.; Anderson, Michael T.

    2012-08-01

    This TLR provides an assessment of weld overlays as a mitigation strategy for PWSCC, and includes an assessment of the WOL-related inspection requirements of Code Case N-770-1, as conditioned in §50.55a.

  3. The migration law of overlay rock and coal in deeply inclined coal seam with fully mechanized top coal caving.

    Science.gov (United States)

    Liu, Jian; Chen, Shan-Le; Wang, Hua-Jun; Li, Yu-Cheng; Geng, Xiaowei

    2015-07-01

    In a mine area, some environment geotechnics problems always occure, induced by mined-out region such as the subsidence and cracks at ground level, deformation and destruction of buildings, landslides destruction of water resources and the ecological environment. In order to research the migration of surrounding rock and coal in steeply inclined super high seams which used fully mechanized top coal caving, a working face of a certain mine was made as an example, analyzed the migration law of the overlay rock and coal under different caving ratio of fully mechanized top coal caving with numerical simulation analysis. The results suggest that the laws of overlay rock deformation caused by deeply inclined coal seam were different from horizontal coal seam. On the inclined direction, with an increase of dip angle and caving ratio, the vertical displacement of overlay rock and coal became greater, the asymmetric phenomenon of vertical displacement became obvious. On the trend direction, active region and transition region in goaf became smaller along with the increase of mining and caving ratio. On the contrary, the stable region area became greater. Therefore, there was an essential difference between the mechanism of surface movement deformation with deeply inclined coal seam and that with horizontal coal seam.

  4. Underlay-friendly Overlay routing mechanism for IP networks%一种IP网络友好的Overlay路由机制

    Institute of Scientific and Technical Information of China (English)

    徐同亚; 王大彬; 陈超

    2011-01-01

    在现存的多层路由中,上层Overlay网络在路由决策时通常对底层的IP网络性能和状态缺乏有效的协调和感知,致使上层Overlay路由和底层IP路由常常处于非协同、非优化工作状态,产生大量路由抖动和次优路由.为解决这些问题,提出了一种底层IP网络友好的Overlay路由机制,其基本思路为:增加Overlay网络的层感知能力,减少路由抖动,增加Overlay路由的稳定性.Overlay网络根据底层IP网络的节点跳数、链路带宽、丢包率等反映底层IP网络性能的信息作出路由决策.实际网络中,通过调整Overlay网络的链路代价,有效控制Overlay网络的路由决策.仿真结果表明,与传统双重路由(dual routing)相比,此IP网络友好Overlay路由机制在减少Overlay网络路由抖动、降低Overlay网络路径代价膨胀、提高Overlay网络故障恢复成功率和满足Overlay业务需求等方面有优势.%Existent Overlay networks are not IP network-aware enough..The Overlay routing is usually lack of aware of the IP network' s performance and status.So the Overlay network appears sub-optimal routing and has route flaps that have seriously affected the Overlay network applications' performance.This paper proposed an IP network-friendly Overlay routing mechanism.The basic idea was: enhance the Overlay network' s ability of lay awareness and flexibility.Overlay network routes based on the IP.network' s information (e.g.: number of route hops, link bandwidth and packet loss rate).Changing the Overlay network' s linkcost was useful to control the Overlay routing.The simulation results show that: compared to the traditional dual routing, this IP network-friendly Overlay routing mechanism has advantages in reducing the path cost inflation and route flaps, increasing the success rate of recovery, meeting the need of Overlay applications.

  5. Initial experience with circumferential pulmonary vein isolation guided by Overlay Ref and CartoMerge in the treatment of paroxysmal atrial fibrillation

    Institute of Scientific and Technical Information of China (English)

    TANG Kai; ZHAO Dong-dong; ZHANG Jing-ying; CHEN Yan-qing; XU Ya-wei

    2010-01-01

    Background CartoMerge has been widely used in guiding circumferential pulmonary vein isolation (CPVI) for the treatment of paroxysmal atrial fibrillation (PAF).However, the procedure of landmarks selection varies among operators according to their experience.Techniques have to be established to standardize this procedure.We propose that Overlay Ref could facilitate this procedure.This paper aimed to report our initial experience with CPVI guided by Overlay Ref and CartoMerge for the treatment of PAF.Methods Fifty-nine patients with PAF were enrolled in this study.Using Overlay Ref technique, a reference image (inverted) was faded into the live fluoroscopic image.Landmarks of CartoMerge were selected from anatomic points of the top of superior pulmonary veins (PVs) and the bottom of inferior PVs guided by Overlay Ref image.Overlay Ref images were also used to guide the ablation procedure combining with CartoMerge.Results All patients were successfully mapped by CartoMerge guided by Overlay Ref.The distance between the mapping points and the CT surfaces was (1.42±0.67) mm for the patients as a whole.This led to a successful rate of 96%for isolation of pulmonary veins.Duration of ablation procedure was (92±17) minutes.And the total duration of procedure was (139±32) minutes.CartoMerge could also be performed just with 3 paries to 4 paries selected landmarks guided by Overlay Ref without a full anatomic model constructed by Carto.Then, the total duration of procedure could be shortened to (115±38) minutes.Conclusions Overlay Ref technique can facilitate the catheter ablation of PAF and can help to standardize the procedure of landmarks selection.

  6. Comparison of dual-energy CT-derived iodine content and iodine overlay of normal, inflammatory and metastatic squamous cell carcinoma cervical lymph nodes

    Energy Technology Data Exchange (ETDEWEB)

    Tawfik, Ahmed M. [Johan Wolfgang Goethe University Hospital, Department of Diagnostic and Interventional Radiology, Frankfurt am Main, Hessen (Germany); Mansoura University Hospital, Department of Diagnostic and Interventional Radiology, Mansoura (Egypt); Razek, A.A. [Mansoura University Hospital, Department of Diagnostic and Interventional Radiology, Mansoura (Egypt); Kerl, J.M.; Nour-Eldin, N.E.; Bauer, Ralf; Vogl, Thomas J. [Johan Wolfgang Goethe University Hospital, Department of Diagnostic and Interventional Radiology, Frankfurt am Main, Hessen (Germany)

    2014-03-15

    To evaluate whether dual-energy computed tomography (DECT)-derived iodine content and iodine overlay could differentiate between normal, inflammatory and metastatic squamous cell carcinoma (SCC) cervical lymph nodes. This study was approved by the institutional review board. Sixteen patients with normal lymph nodes, 20 patients with enlarged nodes draining deep cervical inflammations and 23 patients with pathologically proved metastatic SCC nodes who underwent contrast enhanced DECT were retrospectively identified. Iodine content and overlay of 36 normal, 43 inflammatory and 52 metastatic lymph nodes were calculated using circular regions of interest and compared among the three groups. A receiver operating characteristic (ROC) curve was used to determine the sensitivity and specificity of iodine content and overlay for diagnosis of metastatic nodes. Iodine content (mg/ml) was significantly lower for metastatic lymph nodes (2.34 ± 0.45) than for normal (2.86 ± 0.37) and inflammatory (3.53 ± 0.56) lymph nodes, P < 0.0001. Iodine overlay (HU) was also significantly lower for metastatic lymph nodes (47 ± 11.6) than normal (57.4 ± 8.2) and inflammatory nodes (69.3 ± 11.5), P < 0.0001. The areas under the ROC curve for iodine content and iodine overlay were 0.923 and 0.896. DECT-derived iodine content and overlay differ significantly among normal, inflammatory and metastatic SCC cervical lymph nodes. (orig.)

  7. Hydrophilic property of SiO2-TiO2 overlayer films and TiO2/SiO2 mixing films

    Institute of Scientific and Technical Information of China (English)

    关凯书; 徐宏; 吕宝君

    2004-01-01

    The photo-induced hydrophilicity of SiO2 overlayer on TiO2 films prepared by sol-gel method was investigated by means of soak angle measurement, XPS, UV-VIS and FTIR spectra. The results show that, compared with the TiO2 film without SiO2 overlayer, when the TiO2 film is thoroughly covered by SiO2 overlayer, the hydrophilicity and the sustained effect are enhanced. It is found that the significant growth of the OH group occurs in the surface of SiO2 overlayer. The different mechanism of enhanced hydrophilicity between SiO2 overlayer on TiO2 films and TiO2/SiO2 mixing films was analyzed. The result suggests that the photo-generated electrons created in the interface between TiO2 and SiO2 tend to reduce the Ti(Ⅳ) cation to the Ti(Ⅲ) state, and the photogenerated holes transmit through the SiO2 layer to uppermost surface efficiently. Once the holes go up to the surface, they tend to make the surface hydrophilic. The stable hydrophilicity of SiO2 overlayer which adsorbs more stable OH groups, enhances the sustained effect, i.e. the super-hydrophilic state can be maintained for a long time in dark place.

  8. Thermo-mechanical behavior of bituminous mixtures at low temperatures. Links between the binder characteristics and the mix properties; Comportement thermomecanique des enrobes bitumeux a basses temperatures: relations entre les proprietes du liant et de l'enrobe

    Energy Technology Data Exchange (ETDEWEB)

    Olard, F.

    2003-10-01

    This thesis has been realized within the framework of a partnership between the Ecole Nationale des TPE, APPIA and EUROVIA. The company Total has also been associated to this project. The study deals with the thermo-mechanical behavior of bituminous materials at low temperatures. The aim is to establish the links between the characteristics of the binder and the properties of bituminous mixes at low temperatures, and to better understand the existing low-temperature parameters and criteria for binders (or to propose new ones), related to the in-situ behavior of bituminous mixtures. A large experimental campaign has been carried out so as to fulfill this goal. After a bibliographical study on the rheology and the thermo-mechanical properties of (pure or modified) binders, putties and mixes, the experimental campaign carried out both in the small strain domain and in the large strain domain, is presented. The low temperature behavior of binders has been evaluated with three common fundamental tests: i)the complex modulus determination, ii)the Bending Beam Rheometer and iii)the tensile strength at a constant strain rate and constant temperatures. A new three point bending test on pre-notched bitumen beams has also been developed at the ENTPE. The low-temperature fracture properties of bitumens were studied at constant temperatures and cross-head speeds considering the Linear Elastic Fracture Mechanics (LEFM) assumptions. The thermo-mechanical behavior of bituminous mixtures has been studied by performing i)complex modulus tests, ii)measurements of the coefficient of thermal dilatation and contraction, iii)tensile tests at constant temperatures and strain rates, and iv)Thermal Stress Restrained Specimen Tests. Apart from the determination of some pertinent links between binder and mix properties and discriminating characteristics with regard to the thermal cracking of bituminous mixes at low temperatures, the analysis has also consisted in modeling the behavior of

  9. Digital reconstructed radiography with multiple color image overlay for image-guided radiotherapy.

    Science.gov (United States)

    Yoshino, Shinichi; Miki, Kentaro; Sakata, Kozo; Nakayama, Yuko; Shibayama, Kouichi; Mori, Shinichiro

    2015-05-01

    Registration of patient anatomical structures to the reference position is a basic part of the patient set-up procedure. Registration of anatomical structures between the site of beam entrance on the patient surface and the distal target position is particularly important. Here, to improve patient positional accuracy during set-up for particle beam treatment, we propose a new visualization methodology using digitally reconstructed radiographs (DRRs), overlaid DRRs, and evaluation of overlaid DRR images in clinical cases. The overlaid method overlays two DRR images in different colors by dividing the CT image into two CT sections at the distal edge of the target along the treatment beam direction. Since our hospital uses fixed beam ports, the treatment beam angles for this study were set at 0 and 90 degrees. The DRR calculation direction was from the X-ray tube to the imaging device, and set to 180/270 degrees and 135/225 degrees, based on the installation of our X-ray imaging system. Original and overlaid DRRs were calculated using CT data for two patients, one with a parotid gland tumor and the other with prostate cancer. The original and overlaid DRR images were compared. Since the overlaid DRR image was completely separated into two regions when the DRR calculation angle was the same as the treatment beam angle, the overlaid DRR visualization technique was able to provide rich information for aiding recognition of the relationship between anatomical structures and the target position. This method will also be useful in patient set-up procedures for fixed irradiation ports.

  10. Preconversion processing of bituminous coals: New directions to improved direct catalytic coal liquefaction. Final report, September 20, 1991--September 19, 1993

    Energy Technology Data Exchange (ETDEWEB)

    1993-09-01

    One of the main goals for competitive coal liquefaction is to decrease gas yields to reduce hydrogen consumption. Complexing this element as methane and ethane decreases process efficiently and is less cost effective. To decrease the gas yield and increase the liquid yield, an effective preconversion process has been explored on the basis of the physically associated molecular nature of coal. Activities have been focused on two issues: (1) maximizing the dissolution of associated coal and (2) defining the different reactivity associated with a wide molecular weight distribution. Two-step soaking at 350{degrees}C and 400{degrees}C in a recycle oil was found to be very effective for coal solubilization. No additional chemicals, catalysts, and hydrogen are required for this preconversion process. High-volatile bituminous coals tested before liquefaction showed 80--90% conversion with 50--55% oil yields. New preconversion steps suggested are as follows: (1) dissolution of coal with two-step high-temperature soaking, (2) separation into oil and heavy fractions of dissolved coal with vacuum distillation, and (3) selective liquefaction of the separated heavy fractions under relatively mild conditions. Laboratory scale tests of the proposed procedure mode using a small autoclave showed a 30% increase in the oil yield with a 15--20% decrease in the gas yield. This batch operation projects a substantial reduction in the ultimate cost of coal liquefaction.

  11. Size-resolved Pb distribution in the Athabasca River shows snowmelt in the bituminous sands region an insignificant source of dissolved Pb

    Science.gov (United States)

    Javed, Muhammad Babar; Cuss, Chad W.; Grant-Weaver, Iain; Shotyk, William

    2017-01-01

    Lead (Pb) is a metal of special importance because of its long history of commercial and industrial use, global atmospheric contamination accelerated by the use of gasoline additives, and health effects, with children being especially vulnerable. Global atmospheric Pb pollution reached its zenith in the 1970’s, but subsequent impacts on freshwater aquatic systems are poorly understood. Employing metal-free sampling and handling protocols, we show that snowmelt from the Athabasca bituminous sands region is an insignificant source of dissolved Pb to the Athabasca River (AR). Total Pb in the AR is low, and almost entirely in particulate form. Lead in the suspended solids in the AR exactly follows thorium (Th), a conservative lithophile element, and a linear regression of Pb against Th (Pb = 1.6 × Th + 0.0; R2 = 0.99) yields a slope identical to the Pb/Th ratio in the Upper Continental Crust. In the “dissolved” fraction, the Pb/Th ratio is equivalent to that of deep, open ocean seawater; and dominated by colloidal forms. Taken together, these results show that the efforts of recent decades to reduce anthropogenic Pb to the environment have been successful: Pb loading to the river can now be explained predominantly by natural processes, namely erosion plus chemical weathering. PMID:28262714

  12. The use of μCT and ESEM in the study of the osmosis-induced water uptake by Eurobitum bituminized radioactive waste.

    Science.gov (United States)

    Mariën, An; Valcke, Elie; Bleyen, Nele; Van Geet, Maarten; Wevers, Martine

    2012-10-01

    Laboratory water uptake tests are performed at the Belgian Nuclear Research Centre SCK•CEN to obtain insight into the hydromechanical behavior of Eurobitum bituminized radioactive waste under geological disposal conditions. Small nonradioactive and radioactive Eurobitum samples are hydrated in restricted swelling conditions (i.e., nearly constant volume conditions and constant stress conditions). Microfocus X-ray computer tomography (μCT) proves to be a very suitable technique to follow up the ingress of water in the samples. μCT analyses demonstrate that, under the studied hydration conditions, the water uptake by Eurobitum samples is a diffusion controlled process. A characterization of the partially leached samples with environmental scanning electron microscopy (ESEM) shows that the hydration of salt crystals and the subsequent dilution of the salt solution result in an increase in pore size that is limited to a few tens of μm in restricted swelling conditions. The μCT and ESEM analyses allow improvement in the understanding of water uptake by Eurobitum in restricted swelling conditions. In this article we discuss the μCT and ESEM analyses of nonradioactive Eurobitum samples that were hydrated for 2 to 4 years at a constant stress of 1, 22, 33, and 44 bar or in nearly constant volume conditions.

  13. Development of a method to determine the nuclide inventory in bituminized waste packages; Entwicklung eines Verfahrens zur Bestimmung des Nuklidinventars in bituminierten Abfallgebinden

    Energy Technology Data Exchange (ETDEWEB)

    Mesalic, E.; Kortman, F.; Lierse von Gostomski, C. [Technische Univ. Muenchen, Garching (Germany). Zentrale Technisch-Wissenschaftliche Betriebseinheit Radiochemie Muenchen (RCM)

    2014-01-15

    Until the 1980s, bitumen was used as a conditioning agent for weak to medium radioactive liquid waste. Its use can be ascribed mainly to the properties that indicated that the matrix was optimal. However, fires broke out repeatedly during the conditioning process, so that the method is meanwhile no longer permitted in Germany. There are an estimated 100 waste packages held by the public authorities in Germany that require a supplementary declaration. In contrast to the common matrices, such as for example resins or sludges, there is still no standardized technology for taking samples and subsequently determining the radio-nuclide for bitumen. Aspects, such as the thermoplastic behaviour, make determining the nuclide inventory more difficult in bituminized waste packages. The development of a standardized technology to take samples with a subsequent determination of the radio-nuclide analysis is the objective of a project funded by the BMBF. Known, new methods, specially developed for the project, are examined on inactive bitumen samples and then transferred to active samples. At first non-destructive methods are used. The resulting information forms an important basis to work out and apply destructive strategy for sampling and analysis. Since the project is on-going, this report can only address the development of the sampling process. By developing a sampling system, it will be possible to take samples from an arbitrary selected location of the package across the entire matrix level and thus gain representative analysis material. The process is currently being optimized. (orig.)

  14. Size-resolved Pb distribution in the Athabasca River shows snowmelt in the bituminous sands region an insignificant source of dissolved Pb.

    Science.gov (United States)

    Javed, Muhammad Babar; Cuss, Chad W; Grant-Weaver, Iain; Shotyk, William

    2017-03-06

    Lead (Pb) is a metal of special importance because of its long history of commercial and industrial use, global atmospheric contamination accelerated by the use of gasoline additives, and health effects, with children being especially vulnerable. Global atmospheric Pb pollution reached its zenith in the 1970's, but subsequent impacts on freshwater aquatic systems are poorly understood. Employing metal-free sampling and handling protocols, we show that snowmelt from the Athabasca bituminous sands region is an insignificant source of dissolved Pb to the Athabasca River (AR). Total Pb in the AR is low, and almost entirely in particulate form. Lead in the suspended solids in the AR exactly follows thorium (Th), a conservative lithophile element, and a linear regression of Pb against Th (Pb = 1.6 × Th + 0.0; R(2) = 0.99) yields a slope identical to the Pb/Th ratio in the Upper Continental Crust. In the "dissolved" fraction, the Pb/Th ratio is equivalent to that of deep, open ocean seawater; and dominated by colloidal forms. Taken together, these results show that the efforts of recent decades to reduce anthropogenic Pb to the environment have been successful: Pb loading to the river can now be explained predominantly by natural processes, namely erosion plus chemical weathering.

  15. Experience in overlay tympanoplasty%筋膜外植法鼓室成形术的手术体会

    Institute of Scientific and Technical Information of China (English)

    彭本刚; 苗旭涛; 王欣; 孙轶青; 刘志莹; 李永新

    2009-01-01

    Objective To explore the experience and value of overlay tympanoplasty. Methods Sixty-three ears with overlay tympanoplasty were reviewed and followed up for the external auditory canal, tympanic membrane and hearing. Results The diseases of the patients included middle ear cholesteatoma in 25 ears and chronic suppurative otitis media in 38 ears. The surgical techniques involved three kinds: overlay tympanoplasty, overlay tympanoplasty with canal wall up mastoidectomy and overlay tympanoplasty with canal wall down mastoidectomy. In middle ear cholesteatoma and suppurative otitis media patients, the case received the three techniques are 4, 17, 4 ears and 19, 18, 1 ears respectively. All patients gained stage Ⅰ incision cure. Followed up for 0.5 to 3.5 years respectively, the external auditory canal was wide and tympanic membrane gained a good shape. The hearing in all case kept intact or increased while hearing decrease did not occur. Complications were free in patients with punctual visit. Conclusions Overlay tympanoplasty has positive significance in treating the chronic otitis media with the merits of standard procedure, sufficient operative field and thorough erosion elimination.%目的 探讨筋膜外植法在鼓室成形术中的应用及价值.方法 回顾分析筋膜外植法鼓室成形术63耳,随访观察患者的外耳道宽敞度、鼓膜形态及听力恢复情况.结果 本组病例包括中耳胆脂瘤25耳,慢性化脓性中耳炎38耳.手术方式分别为筋膜外植法鼓室成形术、筋膜外植法鼓窜成形术+完肇式乳突根治术和筋膜外植法鼓室成形术+开放式乳突根治术三种类型,中耳胆脂瘤和慢性化脓性中耳炎患者实施三种手术的数最分别为4、17、4耳和19、18、1耳.术后切口全部Ⅰ期愈合.随访0.5~3.5年,外耳道宽敞,鼓膜形态良好,听力提高或维持术前水平,未有听力下降者.按时随访者未发现有明显并发症.结论 筋膜外植法鼓室成形术

  16. Survival Rate of Resin and Ceramic Inlays, Onlays, and Overlays: A Systematic Review and Meta-analysis.

    Science.gov (United States)

    Morimoto, S; Rebello de Sampaio, F B W; Braga, M M; Sesma, N; Özcan, M

    2016-08-01

    This systematic review and meta-analysis aimed to evaluate the survival rate of ceramic and resin inlays, onlays, and overlays and to identify the complication types associated with the main clinical outcomes. Two reviewers searched PubMed, EMBASE, and the Cochrane Central Register of Controlled Trials for articles published between 1983 through April 2015, conforming to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines for systematic reviews. Clinical studies meeting the following criteria were included: 1) studies related to resin and ceramic inlays, onlays, and overlays; 2) prospective, retrospective, or randomized controlled trials conducted in humans; 3) studies with a dropout rate of less than 30%; and 4) studies with a follow-up longer than 5 y. Of 1,389 articles, 14 met the inclusion criteria. The meta-regression indicated that the type of ceramic material (feldspathic porcelain vs. glass-ceramic), study design (retrospective vs. prospective), follow-up time (5 vs. 10 y), and study setting (university vs. private clinic) did not affect the survival rate. Estimated survival rates for glass-ceramics and feldspathic porcelain were between 92% and 95% at 5 y (n = 5,811 restorations) and were 91% at 10 y (n = 2,154 restorations). Failures were related to fractures/chipping (4%), followed by endodontic complications (3%), secondary caries (1%), debonding (1%), and severe marginal staining (0%). Odds ratios (95% confidence intervals) were 0.19 (0.04 to 0.96) and 0.54 (0.17 to 1.69) for pulp vitality and type of tooth involved (premolars vs. molars), respectively. Ceramic inlays, onlays, and overlays showed high survival rates at 5 y and 10 y, and fractures were the most frequent cause of failure.

  17. Photoemission from real iron surfaces and its relationship to light penetration of the overlayer

    Science.gov (United States)

    Momose, Yoshihiro; Suzuki, Daisuke; Sakurai, Takao; Nakayama, Keiji

    2015-02-01

    We report the photoemission from real iron surfaces at elevated temperatures, called thermally assisted photoemission (TAPE), and its relationship to the X-ray photoelectron spectroscopy (XPS) results. TAPE measurements were carried out using a Geiger counter under a gaseous atmosphere of He containing 1 % isobutane vapor at normal atmospheric pressure. A sample was initially heated to temperatures ranging from 25 to 353 °C under light irradiation at a certain wavelength of 200, 210, 220, and 230 nm, and then, wavelength was scanned from 300 to 170 nm at the final temperature. The values of a constant related to electron photoemission probability, αA, where A is identical with the Richardson constant, and photothreshold (photoelectric work function), ϕ, were obtained from a plot of the square root of the electron photoemission intensity against the photon energy; the αA values increased with temperature, and the ϕ values also increased with temperature. From the Arrhenius plot, the αA was found to have an activation energy Δ E αA = 0.096 eV. The activation energies of the surface oxygen component ratio Z = O2-/(OH + O2-) and the surface elemental composition ratio X = Fe/(O + N + C + Fe) obtained from the XPS data were also determined from their Arrhenius plots: Δ E Z = 0.113 eV and Δ E X = 0.039 eV, respectively. From a close resemblance between the latter activation energies and those of the Δ E αA and the Δ E a = 0.112-0.040 eV for the quantum yields (Momose et al. in Appl Phys A. doi: 10.1007/s00339-014-8589-7, 2014), it was found that the increase in the intensity of the TAPE with temperature was strongly associated with the increase in the values of Z and X with temperature. It was therefore concluded that the ability of the surface overlayer to pass the incident light became a rate-determining step to start the photoemission, which was decisively controlled by the temperature-dependent surface oxygen components and surface compositions. The

  18. Investigation on synchronization of the offset printing process for fine patterning and precision overlay

    Science.gov (United States)

    Kang, Dongwoo; Lee, Eonseok; Kim, Hyunchang; Choi, Young-Man; Lee, Seunghyun; Kim, Inyoung; Yoon, Dukkyun; Jo, Jeongdai; Kim, Bongmin; Lee, Taik-Min

    2014-06-01

    Offset printing processes are promising candidates for producing printed electronics due to their capacity for fine patterning and suitability for mass production. To print high-resolution patterns with good overlay using offset printing, the velocities of two contact surfaces, which ink is transferred between, should be synchronized perfectly. However, an exact velocity of the contact surfaces is unknown due to several imperfections, including tolerances, blanket swelling, and velocity ripple, which prevents the system from being operated in the synchronized condition. In this paper, a novel method of measurement based on the sticking model of friction force was proposed to determine the best synchronized condition, i.e., the condition in which the rate of synchronization error is minimized. It was verified by experiment that the friction force can accurately represent the rate of synchronization error. Based on the measurement results of the synchronization error, the allowable margin of synchronization error when printing high-resolution patterns was investigated experimentally using reverse offset printing. There is a region where the patterning performance is unchanged even though the synchronization error is varied, and this may be viewed as indirect evidence that printability performance is secured when there is no slip at the contact interface. To understand what happens at the contact surfaces during ink transfer, the deformation model of the blanket's surface was developed. The model estimates how much deformation on the blanket's surface can be borne by the synchronization error when there is no slip at the contact interface. In addition, the model shows that the synchronization error results in scale variation in the machine direction (MD), which means that the printing registration in the MD can be adjusted actively by controlling the synchronization if there is a sufficient margin of synchronization error to guarantee printability. The effect of

  19. Metagenomic and geochemical characterization of pockmarked sediments overlaying the Troll petroleum reservoir in the North Sea

    Directory of Open Access Journals (Sweden)

    Håvelsrud Othilde

    2012-09-01

    Full Text Available Abstract Background Pockmarks (depressions in the seabed have been discovered throughout the world’s oceans and are often related to hydrocarbon seepage. Although high concentrations of pockmarks are present in the seabed overlaying the Troll oil and gas reservoir in the northern North Sea, geological surveys have not detected hydrocarbon seepage in this area at the present time. In this study we have used metagenomics to characterize the prokaryotic communities inhabiting the surface sediments in the Troll area in relation to geochemical parameters, particularly related to hydrocarbon presence. We also investigated the possibility of increased potential for methane oxidation related to the pockmarks. Five metagenomes from pockmarks and plain seabed sediments were sequenced by pyrosequencing (Roche/454 technology. In addition, two metagenomes from seabed sediments geologically unlikely to be influenced by hydrocarbon seepage (the Oslofjord were included. The taxonomic distribution and metabolic potential of the metagenomes were analyzed by multivariate analysis and statistical comparisons to reveal variation within and between the two sampling areas. Results The main difference identified between the two sampling areas was an overabundance of predominantly autotrophic nitrifiers, especially Nitrosopumilus, and oligotrophic marine Gammaproteobacteria in the Troll metagenomes compared to the Oslofjord. Increased potential for degradation of hydrocarbons, especially aromatic hydrocarbons, was detected in two of the Troll samples: one pockmark sample and one from the plain seabed. Although presence of methanotrophic organisms was indicated in all samples, no overabundance in pockmark samples compared to the Oslofjord samples supports no, or only low level, methane seepage in the Troll pockmarks at the present time. Conclusions Given the relatively low content of total organic carbon and great depths of hydrocarbon containing sediments in the Troll

  20. The role of carbon overlayers on Pt-based catalysts for H2-cleanup by CO-PROX

    Science.gov (United States)

    Romero-Sarria, F.; Garcia-Dali, S.; Palma, S.; Jimenez-Barrera, E. M.; Oliviero, L.; Bazin, P.; Odriozola, J. A.

    2016-06-01

    In this work, we analyze the effect of the activation method on the catalytic activity of Pt-based catalysts supported on alumina in the PROX reaction. For this, model Pt/Al2O3 catalysts with variable amounts of acetic acid were prepared and their thermal evolution studied by FTIR spectroscopy. From the analysis of the nature of the platinum surface upon acetic acid decomposition and the gas phase evolved products, we have demonstrated the formation of partially hydrogenated carbon overlayers that tailor the activity of Pt-based catalysts in the PROX reaction.

  1. Electronic and structural characterizations of unreconstructed {l_brace}0001{r_brace} surfaces and the growth of graphene overlayers

    Energy Technology Data Exchange (ETDEWEB)

    Emtsev, Konstantin

    2009-06-03

    The present work is focused on the characterization of the clean unreconstructed SiC{l_brace}0001{r_brace} surfaces and the growth of graphene overlayers thereon. Electronic properties of SiC surfaces and their interfaces with graphene and few layer graphene films were investigated by means of angle resolved photoelectron spectroscopy, X-ray photoelectron spectroscopy and low energy electron diffraction. Structural characterizations of the epitaxial graphene films grown on SiC were carried out by atomic force microscopy and low energy electron microscopy. Supplementary data was obtained by scanning tunneling microscopy. (orig.)

  2. Impact of Solvent on Photocatalytic Mechanisms: Reactions of Photodesorption Products with Ice Overlayers on the TiO2(110) Surface

    Energy Technology Data Exchange (ETDEWEB)

    Shen, Mingmin; Henderson, Michael A.

    2011-04-07

    The effects of water and methanol ice overlayers on the photodecomposition of acetone on rutile TiO2(110) were evaluated in ultrahigh vacuum (UHV) using photon stimulated desorption (PSD) and temperature programmed desorption (TPD). In the absence of ice overlayers, acetone photodecomposed on TiO2(110) at 95 K by ejection of a methyl radical into the gas phase and formation of acetate on the surface. With ice overlayers, the methyl radicals are trapped at the interface between TiO2(110) and the ice. When water ice was present, these trapped methyl radicals reacted either with each other to form ethane or with other molecules in the ice (e.g., water or displaced acetone) to form methane (CH4), ethane (CH3CH3) and other products (e.g., methanol), with all of these products trapped in the ice. The new products were free to revisit the surface or depart during desorption of the ice. When methanol ice was present, methane formation came about only from reaction of trapped methyl radicals with the methanol ice. Methane and ethane slowly leaked through methanol ice overlayers into vacuum at 95 K, but not through water ice overlayers. Different degrees of site competition between water and acetone, and between methanol and acetone led to different hydrogen abstraction pathways in the two ices. These results provide new insights into product formation routes and solution-phase radical formation mechanisms that are important in heterogeneous photocatalysis.

  3. Recovery bituminous coal fines: a discussion on the production of coal-water slurry fuels and its relationship to fine coal cleaning

    Energy Technology Data Exchange (ETDEWEB)

    Morrison, J.L.; Scaroni, A.W.; Battista, J.J. [Pennsylvania State University, University Park, PA (United States)

    1998-12-31

    The recovery of bituminous coal fines from slurry impoundments and fine coal cleaning circuits has received considerable attention over the last decade from both coal suppliers and coal-fired utilities. Several coal-fired utilities are presently determining whether a low-solids, low viscosity coal-water slurry fuel (CWSF) produced from fine coal can be co-fired with their normal coal feedstock in order to lower their fuel cost and reduce their NO{sub x} emissions. One of the most visible CWSF demonstration programs in the United States is being conducted by GPU Generating, Inc. (GPU Genco). GPU Genco has conducted intermittent demonstration co-fire testing at their 218 MWe-Seward Station since 1993. These tests successfully demonstrate that a low-solids CWSF can be co-fired with pulverized coal in wall-and tangentially-fired boilers. The majority of the CWSF tested at Seward has been prepared from impounded coal fines cleaned via froth flotation and, on a more limited basis, a CWSF prepared from coal fines concentrated from a screen-bowl centrifuge effluent. The production of alow-solids CWSF from wet, fine coal provides an alternative to dewatering. This paper summarizes several fine coal recovery and utilization programs conducted by Pennsylvania State University (Penn State) and GPU Genco during the last five years. These programs range from performing bench-to-pilot-scale cleanability and pilot-scale combustion testing to full-scale utility demonstration tests. All of these successful programs have a common thread of integrating and addressing the issues of fine coal characterization, cleaning handling, and the combustion performance of the CWSF. 8 refs., 1 fig., 1 tab.

  4. Impacts of halogen additions on mercury oxidation, in a slipstream selective catalyst reduction (SCR), reactor when burning sub-bituminous coal.

    Science.gov (United States)

    Cao, Yan; Gao, Zhengyang; Zhu, Jiashun; Wang, Quanhai; Huang, Yaji; Chiu, Chengchung; Parker, Bruce; Chu, Paul; Pant, Wei-Ping

    2008-01-01

    This paper presents a comparison of impacts of halogen species on the elemental mercury (Hg(0)) oxidation in a real coal-derived flue gas atmosphere. It is reported there is a higher percentage of Hg(0) in the flue gas when burning sub-bituminous coal (herein Powder River Basin (PRB) coal) and lignite, even with the use of selective catalytic reduction (SCR). The higher Hg(0)concentration in the flue gas makes it difficult to use the wet-FGD process for the mercury emission control in coal-fired utility boilers. Investigation of enhanced Hg(0) oxidation by addition of hydrogen halogens (HF, HCl, HBr, and HI) was conducted in a slipstream reactor with and without SCR catalysts when burning PRB coal. Two commercial SCR catalysts were evaluated. SCR catalyst no. 1 showed higher efficiencies of both NO reduction and Hg(0) oxidation than those of SCR catalyst no. 2. NH3 addition seemed to inhibit the Hg(0) oxidation, which indicated competitive processes between NH3 reduction and Hg(0) oxidation on the surface of SCR catalysts. The hydrogen halogens, in the order of impact on Hg(0) oxidation, were HBr, HI, and HCl or HF. Addition of HBr at approximately 3 ppm could achieve 80% Hg(0) oxidation. Addition of HI at approximately 5 ppm could achieve 40% Hg(0) oxidation. In comparison to the empty reactor, 40% Hg(0) oxidation could be achieved when HCl addition was up to 300 ppm. The enhanced Hg(0) oxidation by addition of HBr and HI seemed not to be correlated to the catalytic effects by both evaluated SCR catalysts. The effectiveness of conversion of hydrogen halogens to halogen molecules or interhalogens seemed to be attributed to their impacts on Hg(0) oxidation.

  5. Development of new non destructive methods for bituminized radioactive waste drums characterization; Developpement de nouvelles methodes de caracterisation non destructive pour des dechets radioactifs enrobes dans du bitume

    Energy Technology Data Exchange (ETDEWEB)

    Pin, P

    2004-10-15

    Radioactive waste constitute a major issue for the nuclear industry. One of the key points is their characterization to optimize their management: treatment and packaging, orientation towards the suited disposal. This thesis proposes an evaluation method of the low-energy photon attenuation, based on the gamma-ray spectra Compton continuum. Effectively, the {sup 241}Am measurement by gamma-ray spectrometry is difficult due to the low energy of its main gamma-ray (59.5 keV). The photon attenuation strongly depends on the bituminous mix composition, which includes very absorbing elements. As the Compton continuum also depends on this absorption, it is possible to link the 59.5 keV line attenuation to the Compton level. Another technique is proposed to characterize uranium thanks to its fluorescence X-rays induced by the gamma emitters already present in the waste. The uranium present in the drums disturbs the neutron measurements and its measurement by self-induced X-ray fluorescence allows to correct this interference. Due to various causes of error, the total uncertainty is around 50 % on the activity of the radioisotope {sup 241}Am, corrected by the peak to Compton technique. The same uncertainty is announced on the uranium mass measured by self induced X-ray fluorescence. As a consequence of these promising results, the two methods were included in the industrial project of the 'Marcoule Sorting Unit'. One major advantage is that they do not imply any additional material because they use information already present in the gamma-ray spectra. (author)

  6. Evaluation of Control Strategies to Effectively Meet 70-90% Mercury Reduction on an Eastern Bituminous Coal Cyclone Boiler with SCR

    Energy Technology Data Exchange (ETDEWEB)

    Tom Campbell

    2008-12-31

    This is the final site report for testing conducted at Public Service of New Hampshire's (PSNH) Merrimack Unit 2 (MK2). This project was funded through the DOE/NETL Innovations for Existing Plants program. It was a Phase III project with the goal to develop mercury control technologies that can achieve 50-70% mercury capture at costs 25-50% less than baseline estimates of $50,000-$70,000/lb of mercury removed. While results from testing at Merrimack indicate that the DOE goal was partially achieved, further improvements in the process are recommended. Merrimack burned a test blend of eastern bituminous and Venezuelan coals, for a target coal sulfur content of 1.2%, in its 335-MW Unit 2. The blend ratio is approximately a 50/50 split between the two coals. Various sorbent injection tests were conducted on the flue gas stream either in front of the air preheater (APH) or in between the two in-series ESPs. Initial mercury control evaluations indicated that, without SO3 control, the sorbent concentration required to achieve 50% control would not be feasible, either economically or within constraints specific to the maximum reasonable particle loading to the ESP. Subsequently, with SO{sub 3} control via trona injection upstream of the APH, economically feasible mercury removal rates could be achieved with PAC injection, excepting balance-of-plant concerns. The results are summarized along with the impacts of the dual injection process on the air heater, ESP operation, and particulate emissions.

  7. Improvement of yield of Pleurotus eryngii var. eryngii by substrate supplementation and use of a casing overlay.

    Science.gov (United States)

    Rodriguez Estrada, Alma E; Jimenez-Gasco, Maria del Mar; Royse, Daniel J

    2009-11-01

    Improved yield and biological efficiency (BE) of Pleurotus eryngii var. eryngii were achieved by supplementation of substrate with a commercial delayed-release nutrient and use of a casing overlay. Yield increases of 14% were achieved from cased substrates that were supplemented at time of casing with delayed-release nutrient (Remo's). Use of a casing layer enhanced yield by 141% over non-cased substrates. When casing and substrate supplementation were combined, yield increased 179% over non-cased/non-supplemented substrates. Mushrooms harvested from cased substrates were darker in color and solids contents were lower compared to non-cased substrates. An additional break of mushrooms was harvested from non-cased "spent" substrate by fragmenting and re-supplementing the substrate prior to the application of a casing overlay. Three production methods were compared for their effect on mushroom yield: "standard", "casing" and "casing after first break". Casing of the substrate before first break ("casing" production method) resulted in the highest yield and biological efficiency.

  8. A grid overlay framework for analysis of medical images and its application to the measurement of stroke lesions

    Energy Technology Data Exchange (ETDEWEB)

    Armitage, Paul A. [University of Edinburgh, Western General Hospital, Division of Clinical Neurosciences, School of Molecular and Clinical Medicine, Edinburgh (United Kingdom); University of Sheffield, Academic Unit of Radiology, Sheffield (United Kingdom); Rivers, C.S.; Karaszewski, B.; Thomas, R.G.R.; Lymer, G.K.; Morris, Z.; Wardlaw, J.M. [University of Edinburgh, Western General Hospital, Division of Clinical Neurosciences, School of Molecular and Clinical Medicine, Edinburgh (United Kingdom)

    2012-03-15

    To create and evaluate an interactive software tool for measuring imaging data in situations where hand-drawn region-of-interest measurements are unfeasible, for example, when the structure of interest is patchy with ill-defined boundaries. An interactive grid overlay software tool was implemented that enabled coding of voxels dependent on their imaging appearance with a series of user-defined classes. The Grid Analysis Tool (GAT) was designed to automatically extract quantitative imaging data, grouping the results by tissue class. Inter- and intra-observer reproducibility was evaluated by six observers of various backgrounds in a study of acute stroke patients. The software tool enabled a more detailed classification of the stroke lesion than would be possible with a region-of-interest approach. However, inter-observer coefficients of variation (CVs) were relatively high, reaching 70% in ''possibly abnormal'' tissue and around 15-20% in normal appearing tissues, while intra-observer CVs were no more than 13% in ''possibly abnormal'' tissue and generally less than 1% in normal-appearing tissues. The grid-overlay method overcomes some of the limitations of conventional Region Of Interest (ROI) approaches, providing a viable alternative for segmenting patchy lesions with ill-defined boundaries, but care is required to ensure acceptable reproducibility if the method is applied by multiple observers. (orig.)

  9. Effect of an absorbent overlay on the residual stress field induced by laser shock processing on aluminum samples

    Energy Technology Data Exchange (ETDEWEB)

    Rubio-Gonzalez, C. [Centro de Ingenieria y Desarrollo Industrial, Pie de la Cuesta No. 702, Desarrollo San Pablo, Queretaro, Qro. 76130 (Mexico)]. E-mail: crubio@cidesi.mx; Gomez-Rosas, G. [Departamento de Ciencias Exactas y Tecnologicas, Centro Universitario de los Lagos, Universidad de Guadalajara. Lagos de Moreno Jal. (Mexico); Ocana, J.L. [Departamento de Fisica Aplicada a la Ingenieria Industrial, E.T.S.I.I. Universidad Politecnica de Madrid (Spain); Molpeceres, C. [Departamento de Fisica Aplicada a la Ingenieria Industrial, E.T.S.I.I. Universidad Politecnica de Madrid (Spain); Banderas, A. [Centro de Ingenieria y Desarrollo Industrial, Pie de la Cuesta No. 702, Desarrollo San Pablo, Queretaro, Qro. 76130 (Mexico); Porro, J. [Departamento de Fisica Aplicada a la Ingenieria Industrial, E.T.S.I.I. Universidad Politecnica de Madrid (Spain); Morales, M. [Departamento de Fisica Aplicada a la Ingenieria Industrial, E.T.S.I.I. Universidad Politecnica de Madrid (Spain)

    2006-07-15

    Laser shock processing (LSP) or laser shock peening is a new technique for strengthening metals. This process induces a compressive residual stress field, which increases fatigue crack initiation life and reduces fatigue crack growth rate. Specimens of 6061-T6 aluminum alloy are used in this investigation. A convergent lens is used to deliver 2.5 J, 8 ns laser pulses by a Q-switch Nd:YAG laser, operating at 10 Hz. The pulses are focused to a diameter of 1.5 mm onto aluminum samples. Density of 2500 pulses/cm{sup 2} with infrared (1064 nm) radiation was used. The effect of an absorbent overlay on the residual stress field using this LSP setup and this energy level is evaluated. Residual stress distribution as a function of depth is assessed by the hole drilling method. It is observed that the overlay makes the compressive residual stress profile move to the surface. This effect is explained on the basis of the vaporization of the coat layer suppressing thermal effects on the metallic substrate. The effect of coating the specimen surface before LSP treatment may have advantages on improving wear and contact fatigue properties of this aluminum alloy.

  10. Augmented reality navigation with automatic marker-free image registration using 3-D image overlay for dental surgery.

    Science.gov (United States)

    Wang, Junchen; Suenaga, Hideyuki; Hoshi, Kazuto; Yang, Liangjing; Kobayashi, Etsuko; Sakuma, Ichiro; Liao, Hongen

    2014-04-01

    Computer-assisted oral and maxillofacial surgery (OMS) has been rapidly evolving since the last decade. State-of-the-art surgical navigation in OMS still suffers from bulky tracking sensors, troublesome image registration procedures, patient movement, loss of depth perception in visual guidance, and low navigation accuracy. We present an augmented reality navigation system with automatic marker-free image registration using 3-D image overlay and stereo tracking for dental surgery. A customized stereo camera is designed to track both the patient and instrument. Image registration is performed by patient tracking and real-time 3-D contour matching, without requiring any fiducial and reference markers. Real-time autostereoscopic 3-D imaging is implemented with the help of a consumer-level graphics processing unit. The resulting 3-D image of the patient's anatomy is overlaid on the surgical site by a half-silvered mirror using image registration and IP-camera registration to guide the surgeon by exposing hidden critical structures. The 3-D image of the surgical instrument is also overlaid over the real one for an augmented display. The 3-D images present both stereo and motion parallax from which depth perception can be obtained. Experiments were performed to evaluate various aspects of the system; the overall image overlay error of the proposed system was 0.71 mm.

  11. Sol-Gel-Based Titania-Silica Thin Film Overlay for Long Period Fiber Grating-Based Biosensors.

    Science.gov (United States)

    Chiavaioli, Francesco; Biswas, Palas; Trono, Cosimo; Jana, Sunirmal; Bandyopadhyay, Somnath; Basumallick, Nandini; Giannetti, Ambra; Tombelli, Sara; Bera, Susanta; Mallick, Aparajita; Baldini, Francesco

    2015-12-15

    An evanescent wave optical fiber biosensor based on titania-silica-coated long period grating (LPG) is presented. The chemical overlay, which increases the refractive index (RI) sensitivity of the sensor, consists of a sol-gel-based titania-silica thin film, deposited along the sensing portion of the fiber by means of the dip-coating technique. Changing both the sol viscosity and the withdrawal speed during the dip-coating made it possible to adjust the thickness of the film overlay, which is a crucial parameter for the sensor performance. After the functionalization of the fiber surface using a methacrylic acid/methacrylate copolymer, an antibody/antigen (IgG/anti-IgG) assay was carried out to assess the performance of sol-gel based titania-silica-coated LPGs as biosensors. The analyte concentration was determined from the wavelength shift at the end of the binding process and from the initial binding rate. This is the first time that a sol-gel based titania-silica-coated LPG is proposed as an effective and feasible label-free biosensor. The specificity of the sensor was validated by performing the same model assay after spiking anti-IgG into human serum. With this structured LPG, detection limits of the order of tens of micrograms per liter (10(-11) M) are attained.

  12. Antibacterial effects of allspice, garlic, and oregano essential oils in tomato films determined by overlay and vapor-phase methods.

    Science.gov (United States)

    Du, W-X; Olsen, C W; Avena-Bustillos, R J; McHugh, T H; Levin, C E; Mandrell, R; Friedman, Mendel

    2009-09-01

    Physical properties as well as antimicrobial activities against Escherichia coli O157:H7, Salmonella enterica, and Listeria monocytogenes of allspice, garlic, and oregano essential oils (EOs) in tomato puree film-forming solutions (TPFFS) formulated into edible films at 0.5% to 3% (w/w) concentrations were investigated in this study. Antimicrobial activities were determined by 2 independent methods: overlay of the film on top of the bacteria and vapor-phase diffusion of the antimicrobial from the film to the bacteria. The results indicate that the antimicrobial activities against the 3 pathogens were in the following order: oregano oil > allspice oil > garlic oil. Listeria monocytogenes was less resistant to EO vapors, while E. coli O157:H7 was more resistant to EOs as determined by both overlay and vapor-phase diffusion tests. The presence of plant EO antimicrobials reduced the viscosity of TPFFS at the higher shear rates, but did not affect water vapor permeability of films. EOs increased elongation and darkened the color of films. The results of the present study show that the 3 plant-derived EOs can be used to prepare tomato-based antimicrobial edible films with good physical properties for food applications by both direct contact and indirectly by vapors emanating from the films.

  13. An Investigation of GIS Overlay and PCA Techniques for Urban Environmental Quality Assessment: A Case Study in Toronto, Ontario, Canada

    Directory of Open Access Journals (Sweden)

    Kamil Faisal

    2017-03-01

    Full Text Available The United Nations estimates that the global population is going to be double in the coming 40 years, which may cause a negative impact on the environment and human life. Such an impact may instigate increased water demand, overuse of power, anthropogenic noise, etc. Thus, modelling the Urban Environmental Quality (UEQ becomes indispensable for a better city planning and an efficient urban sprawl control. This study aims to investigate the ability of using remote sensing and Geographic Information System (GIS techniques to model the UEQ with a case study in the city of Toronto via deriving different environmental, urban and socio-economic parameters. Remote sensing, GIS and census data were first obtained to derive environmental, urban and socio-economic parameters. Two techniques, GIS overlay and Principal Component Analysis (PCA, were used to integrate all of these environmental, urban and socio-economic parameters. Socio-economic parameters including family income, higher education and land value were used as a reference to assess the outcomes derived from the two integration methods. The outcomes were assessed through evaluating the relationship between the extracted UEQ results and the reference layers. Preliminary findings showed that the GIS overlay represents a better precision and accuracy (71% and 65%, respectively, comparing to the PCA technique. The outcomes of the research can serve as a generic indicator to help the authority for better city planning with consideration of all possible social, environmental and urban requirements or constraints.

  14. Creating Interactive Graphical Overlays in the Advanced Weather Interactive Processing System (AWIPS) Using Shapefiles and DGM Files

    Science.gov (United States)

    Barrett, Joe H., III; Lafosse, Richard; Hood, Doris; Hoeth, Brian

    2007-01-01

    Graphical overlays can be created in real-time in the Advanced Weather Interactive Processing System (AWIPS) using shapefiles or DARE Graphics Metafile (DGM) files. This presentation describes how to create graphical overlays on-the-fly for AWIPS, by using two examples of AWIPS applications that were created by the Applied Meteorology Unit (AMU). The first example is the Anvil Threat Corridor Forecast Tool, which produces a shapefile that depicts a graphical threat corridor of the forecast movement of thunderstorm anvil clouds, based on the observed or forecast upper-level winds. This tool is used by the Spaceflight Meteorology Group (SMG) and 45th Weather Squadron (45 WS) to analyze the threat of natural or space vehicle-triggered lightning over a location. The second example is a launch and landing trajectory tool that produces a DGM file that plots the ground track of space vehicles during launch or landing. The trajectory tool can be used by SMG and the 45 WS forecasters to analyze weather radar imagery along a launch or landing trajectory. Advantages of both file types will be listed.

  15. Colored overlays for visual perceptual deficits in children with reading disability and attention deficit/hyperactivity disorder: are they differentially effective?

    Science.gov (United States)

    Iovino, I; Fletcher, J M; Breitmeyer, B G; Foorman, B R

    1998-12-01

    The Transient Channel Deficit (TCD) model of reading disability was evaluated by examining the effects of color overlays on the reading ability of four groups of children (n = 15 each) with reading disability and comorbid conditions involving math and ADHD. These 60 children were evaluated for reading accuracy and rate on measures of word decoding and reading comprehension under three color transparency conditions (blue, red, no overlay). Results indicated that color overlays did not differentially affect the reading performance of individuals with and without reading disabilities. However, blue transparencies significantly improved reading comprehension in all groups, and reduced reading rate. These findings indicate that the TCD model may need to be reexamined. An alternative hypothesis for the observed effects, involving facilitation of attention processes, was posted.

  16. GPU加速的多边形叠加分析%Accelerating polygon overlay analysis by GPU

    Institute of Scientific and Technical Information of China (English)

    赵斯思; 周成虎

    2013-01-01

    叠加分析是地理信息系统最重要的分析功能之一,对多边形图层进行叠加分析要花费大量时间.为此,将GPU用于多边形叠加分析过程中的MBR过滤及多边形剪裁两个阶段.对MBR过滤阶段,提出了基于GPU的通过直方图及并行前置和实现的MBR过滤算法.对多边形剪裁阶段,通过改进Weiler-Atherton算法,使用新的焦点插入方法和简化的出入点标记算法,并结合并行前置和算法,提出了基于GPU的多边形剪裁算法.对实现过程中可能出现的负载不均衡情况,给出了基于动态规划的负载均衡方法.通过对这些算法的应用,实现对过滤阶段及精炼阶段的加速.实验结果表明,基于GPU的MBR过滤方法相对CPU实现的加速比为3.8,而基于GPU的多边形剪裁的速度比CPU实现快3.4倍.整体上,与CPU实现相比,GPU加速的多边形叠加提供了3倍以上的加速比.%Overlay analysis is one of the most important analysis capabilities of geographic information systems. Overlay analysis with polygon layers is a time-intensive process. To improve time efficiency, modern approaches of overlay analysis are generally divided into two stages, filtering and refinement (also known as polygon clipping). A great deal of effort has been taken to significantly reduce the number of candidates in the first stage (filtering) in order to alleviate the workload of the second stage (refinement). However, the second stage is still the most time-consuming part of the process. In this paper we applied GPGPU (General-purpose Graphics Processing Unit) computing to the two key stages of overlay analysis: MBR filtering (part of the filtering) and polygon clipping, and restricted the search area to polygon intersection analysis. We proposed GPU-based MBR filtering algorithm by combining histogram and parallel prefix-sum algorithms, and introduced GPU-based polygon clipping algorithm by improving Weiler-Atherton algorithm. There are two differences

  17. Atomistic simulation study of short pulse laser interactions with a metal target under conditions of spatial confinement by a transparent overlayer

    Science.gov (United States)

    Karim, Eaman T.; Shugaev, Maxim; Wu, Chengping; Lin, Zhibin; Hainsey, Robert F.; Zhigilei, Leonid V.

    2014-05-01

    The distinct characteristics of short pulse laser interactions with a metal target under conditions of spatial confinement by a solid transparent overlayer are investigated in a series of atomistic simulations. The simulations are performed with a computational model combining classical molecular dynamics (MD) technique with a continuum description of the laser excitation, electron-phonon equilibration, and electronic heat transfer based on two-temperature model (TTM). Two methods for incorporation of the description of a transparent overlayer into the TTM-MD model are designed and parameterized for Ag-silica system. The material response to the laser energy deposition is studied for a range of laser fluences that, in the absence of the transparent overlayer, covers the regimes of melting and resolidification, photomechanical spallation, and phase explosion of the overheated surface region. In contrast to the irradiation in vacuum, the spatial confinement by the overlayer facilitates generation of sustained high-temperature and high-pressure conditions near the metal-overlayer interface, suppresses the generation of unloading tensile wave, decreases the maximum depth of melting, and prevents the spallation and explosive disintegration of the surface region of the metal target. At high laser fluences, when the laser excitation brings the surface region of the metal target to supercritical conditions, the confinement prevents the expansion and phase decomposition characteristic for the vacuum conditions leading to a gradual cooling of the hot compressed supercritical fluid down to the liquid phase and eventual solidification. The target modification in this case is limited to the generation of crystal defects and the detachment of the metal target from the overlayer.

  18. Co-optimization of RegC and TWINSCAN corrections to improve the intra-field on-product overlay performance

    Science.gov (United States)

    Gorhad, Kujan; Sharoni, Ofir; Dmitriev, Vladimir; Cohen, Avi; van Haren, Richard; Roelofs, Christian; Cekli, Hakki Ergun; Gallagher, Emily; Leray, Philippe; Beyer, Dirk; Trautzsch, Thomas; Steinert, Steffen

    2016-03-01

    Improving wafer On Product Overlay (OPO) is becoming a major challenge in lithography, especially for multipatterning techniques like N-repetitive Litho-Etch steps (LEN, N >= 2). When using different scanner settings and litho processes between inter-layer overlays, intra-field overlay control becomes more complicated. In addition to the Image Placement Error (IPE) contribution, the TWINSCANTM lens fingerprint in combination with the exposure settings is playing a significant role as well. Furthermore the scanner needs to deal with dynamic fingerprints caused by for instance lens and/or reticle heating. This paper will demonstrate the complementary RegC® and TWINSCANTM solution for improving the OPO by cooptimizing the correction capabilities of the individual tools, respectively. As a consequence, the systematic intra-field fingerprints can be decreased along with the overlay (OVL) error at wafer level. Furthermore, the application could be utilized for extending some of the scanner actuators ranges by inducing a pre-determined signatures. These solutions perfectly fit into the ASML Litho InSight (LIS) product in which feedforward and feedback corrections based on YieldStar overlay and other measurements are used to improve the OPO. While the TWINSCANTM scanner corrects for global distortions (up to third order) - scanner Correctable Errors ( CE), the RegC® application can correct for the None Correctable Errors (NCE) by making the high frequency NCE into a CE with low frequency nature. The RegC® induces predictable deformation elements inside the quartz (Qz) material of the reticle, and by doing so it can induce a desired pre-defined signature into the reticle. The deformation introduced by the RegC® is optimized for the actual wafer print taking into account the scale and ortho compensation by the scanner, to correct for the systematic fingerprints and the wafer overlay. These two applications might be very powerful and could contribute to achieve a better

  19. The effect of mold materials on the overlay accuracy of a roll-to-roll imprinting system using UV LED illumination within a transparent mold

    Science.gov (United States)

    Choi, Sungwoo; Kook, YunHo; Kim, ChulHo; Yoo, SoonSung; Park, Kwon-Shik; Kim, Seok-min; Kang, Shinill

    2016-06-01

    Although several studies on the roll-to-roll (R2R) imprinting process have reported achieving flexible electronics, improving the alignment accuracy in the overlay process of R2R imprinting is recognized as the biggest problem for the commercialization of this technology. For an overlay technique with high alignment accuracy, it is essential to develop a roll mold with high positional accuracy. In this study, a method for fabricating a roll mold with high positional accuracy is proposed by wrapping a thin glass substrate flexible mold around the transparent roll base, because it can provide higher mechanical strength and thermal stability than a conventional polymer substrate. To confirm the usability of the proposed process, the prepared roll mold was used to fabricate a test pattern of thin-film transistor backplane for a rollable display. The positional and overlay accuracy of the roll mold with the proposed thin glass substrate flexible mold were compared with the roll mold with a conventional polymer substrate flexible mold. Large-area transparent flexible molds with a size of 470  ×  370 mm were fabricated by an ultraviolet (UV) imprinting process on thin glass and polyethylene terephthalate substrates, and these flexible molds were wrapped around a roll base of 125 mm radius through a precision alignment process. After an anti-adhesion treatment and the wrapping process, the roll mold with the polymer substrate showed a ~180 μm positional error, whereas the thin glass substrate showed a ~30 μm positional error. After the overlay process using the R2R imprinting system with the alignment system, an average overlay error of ~3 μm was obtained when the thin glass flexible wrapped roll mold was used, whereas a ~22 μm overlay error was obtained when the polymer substrate flexible wrapped roll mold was used.

  20. Effect of Some Overlay Welding Regime With Longitudinal Magnetic Field on Hardness, Phase Composition And Welded Layer Wear By Arc Method With Flux Metal Wire

    Science.gov (United States)

    Nosov, D. G.; Peremitko, V. V.; Barashkin, M. H.

    2016-08-01

    The paper defines the range of overlay welding current, frequencies and induction of a longitudinal magnetic field that enhance the wear resistance of welded layer additing the flux. The conditions of their mutual influence on the process of structure formation are stated as well as the mathematical models linking the overlay welding current, frequency and induction of a longitudinal magnetic field with hardness, wear resistance and phase composition of the welded layer, the use of which will allow to determine the welding modes to provide the necessary properties of the weld metal.

  1. Comparative Studies on the Combustion Kinetics of Chars Prepared from Brown and Bituminous Coals under Air (O_2/N_2) and Oxy-fuel (O_2/CO_2) Conditions

    OpenAIRE

    Kim, Hyun-Seok; Wada, Nozomi; Nozawa, Sohey; Matsushita, Yohsuke; Yamamoto, Tsuyoshi; Oomori, Motohira; Harada, Tatsuro; Miyawaki, Jin; Yoon, Seong-Ho; Mochida, Isao

    2012-01-01

    This paper deals with the application of a solid-gas reaction model which can describe the combustion and gasification mechanism for air (O_2/N_2) and oxy-fuel (O_2/CO_2) conditions. Loy Yang brown coal was used as a sample after pyrolysis, together with Newlands coal as bituminous coal for comparison of coal ranks. By carrying out the thermogravimetric analysis (TGA) run under non-isothermal conditions, chemical reaction rates of partial oxidation reaction and gasification reaction were esti...

  2. Evaluation of the AISI 904L Alloy Weld Overlays Obtained by GMAW and Electro-Slag Welding Processes

    Science.gov (United States)

    Jorge, Jorge C. F.; Meira, O. G.; Madalena, F. C. A.; de Souza, L. F. G.; Araujo, L. S.; Mendes, M. C.

    2017-03-01

    The use of superaustenitic stainless steels (SASS) as an overlay replacement for nickel-based alloys can be an interesting alternative for the oil and gas industries, due to its lower cost, when compared to superalloys. Usually, the deposition is made with several welding passes by using conventional arc welding processes, such as gas tungsten arc welding (GTAW) or gas metal arc welding (GMAW) processes. In this respect, electro-slag welding (ESW), which promotes high heat inputs and low dilution of the welds, can also be attractive for this application, as it provides a higher productivity, once only one layer is needed for the deposition of the minimum thickness required. The present work evaluates the behavior of an AISI 904L SASS weld overlay deposited on a carbon steel ASTM A516 Grade 70 by ESW and GMAW processes. Both as-welded and heat-treated conditions were evaluated and compared. A multipass welding by GMAW process with three layers and 48 passes was performed on 12.5 × 200 × 250 mm steel plates with average welding energy of 1.0 kJ/mm. For ESW process, only one layer was deposited on 50 × 400 × 400 mm steel plates with average welding energy of 11.7 kJ/mm. After welding, a post-weld heat treatment (PWHT) at 620 °C for 10 h was performed in half of the steel plate, in order to allow the comparison between this condition and the as-welded one. For both processes, the austenitic microstructure of the weld deposits was characterized by optical microscopy and scanning electron microscopy with electron backscatter diffraction. A low proportion of secondary phases were observed in all conditions, and the PWHT did not promote significant changes on the hardness profile. Martensite for GMAW process and bainite for ESW process were the microstructural constituents observed at the coarse grain heat-affected zone, due to the different cooling rates. For ESW process, no evidences of partially diluted zones were found. As a consequence of the microstructural

  3. Structural features of a bituminous coal and their changes during low-temperature oxidation and loss of volatiles investigated by advanced solid-state NMR spectroscopy

    Science.gov (United States)

    Mao, J.-D.; Schimmelmann, A.; Mastalerz, Maria; Hatcher, P.G.; Li, Y.

    2010-01-01

    Quantitative and advanced 13C solid-state NMR techniques were employed to investigate (i) the chemical structure of a high volatile bituminous coal, as well as (ii) chemical structural changes of this coal after evacuation of adsorbed gases, (iii) during oxidative air exposure at room temperature, and (iv) after oxidative heating in air at 75 ??C. The solid-state NMR techniques employed in this study included quantitative direct polarization/magic angle spinning (DP/MAS) at a high spinning speed of 14 kHz, cross polarization/total sideband suppression (CP/TOSS), dipolar dephasing, CH, CH2, and CHn selection, 13C chemical shift anisotropy (CSA) filtering, two-dimensional (2D) 1H-13C heteronuclear correlation NMR (HETCOR), and 2D HETCOR with 1H spin diffusion. With spectral editing techniques, we identified methyl CCH 3, rigid and mobile methylene CCH2C, methine CCH, quaternary Cq, aromatic CH, aromatic carbons bonded to alkyls, small-sized condensed aromatic moieties, and aromatic C-O groups. With direct polarization combined with spectral-editing techniques, we quantified 11 different types of functional groups. 1H-13C 2D HETCOR NMR experiments indicated spatial proximity of aromatic and alkyl moieties in cross-linked structures. The proton spin diffusion experiments indicated that the magnetization was not equilibrated at a 1H spin diffusion time of 5 ms. Therefore, the heterogeneity in spatial distribution of different functional groups should be above 2 nm. Recoupled C-H long-range dipolar dephasing showed that the fraction of large charcoal-like clusters of polycondensed aromatic rings was relatively small. The exposure of this coal to atmospheric oxygen at room temperature for 6 months did not result in obvious chemical structural changes of the coal, whereas heating at 75 ??C in air for 10 days led to oxidation of coal and generated some COO groups. Evacuation removed most volatiles and caused a significant reduction in aliphatic signals in its DP

  4. Structure and properties of samarium overlayer and Sm/Rh surface alloy on Rh(1O0)

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The structure and properties of Sm overlayer and Sm/Rh surface alloy have been investigated with Auger electron spectroscopy (AES), low energy electron diffraction (LEED), X-ray photoelectron spectroscopy (XPS), and temperature programmed desorption spectroscopy (TDS). The growth of Sm on Rh(100) at room temperature (RT) appears following the Stranski-Krastanov growth mode and only the trivalent state Sm is observed from XPS results. Thermal treatment of the Sm film at 900 K leads to the formation of ordered surface alloy which shows the c(5 2 × 2 )R45°and c(2 × 2) LEED patterns. Annealing the Sm film at temperature above 400 K makes the binding energy (B.E.) of Sm 3d5/2 shift to higher energy by 0.7 eV, which indicates charge transfer from Sm to Rh(100) substrate, causing the increase of CO desorption temperature.

  5. Research on the Impact of Amplitude of Vibrations on Electrical Parameters of Vibroarc Weld Overlay in Argon

    Directory of Open Access Journals (Sweden)

    Nikolov Mitko Ivanov

    2015-06-01

    Full Text Available The research is taken on the vibroarc welding apparatus ENTON-60 equipped with an axial non-inertial vibrator in argon shield. The criteria used for assessing the flow of the electric arc process and the formation of weld overlay clad surfaces are: short circuit voltage, voltage at the start of arc combustion, short circuit amperage, and amperage at the end of arc combustion. Wire electrode‘s vibrating frequency is considered as an input variable of the cybernetic model. It has been found that amplitude of vibrations has a significant impact on the vibroarc process - voltage parameters and welding current ratio, as the minimum amperage of short circuit and the lowest voltage at the start of arc combustion is realized at 2 mm amplitude of vibrations.

  6. The asphalt overlay Engineering construction control points%沥青罩面工程施工控制要点

    Institute of Scientific and Technical Information of China (English)

    朱新春

    2012-01-01

      沥青罩面是近年来发展起来的一种路面养护新技术,所谓沥青罩面就是以一定级配的碎石作为骨料,以沥青作为结合料,利用专业机械或人工撒铺均匀,经过压实后在路面上形成的表面处治层。多年的实践证明,沥青罩面具有良好的使用性能,不仅可以周期性地恢复原路面被磨耗的厚度,还可以处理路面的一般性破损,改善路面的抗滑能力和平整度,尤其在封闭路面龟网裂、防水抗滑、改善路容和增强耐磨性等方面,效果十分良好。此外,它还具有质量好、进度快、成本低、工序简单、开放交通早等显著优点。在这项技术的推广应用方面,我们不断总结经验,努力探讨提高质量、降低成本的方法,使这一技术在公路养护中充分发挥了作用,现就沥青罩面的施工控制谈几点体会。%  A road asphalt overlay is developed in recent years the conservation of new technologies, the so-called asphalt overlay is to a certain level with gravel as aggregate in asphalt as the binder, the use of the professional machinery or artificial Caesar Shop uniform, after Treatment on the road surface formed after compaction layer. Years of practice proved asphalt overlay has good performance, not only periodically restore the original road wear thickness can also handle the general road damage, improve the skid resistance of the road surface and flatness, especially in a closed road turtle net crack, waterproof skid, improve road capacity and enhanced wear resistance, the effect is very good. In addition, it has a good quality, fast progress, low-cost, simple process, open to traffic as early as other notable advantages. Promote the application of this technology, we are con-stantly sum up experience, efforts to explore methods to improve quality, lower costs, making this technology to give full play to the role of road maintenance, construction of the asphalt

  7. Tl overlayers on Si(1-bar 0-bar 0) and their self-assembly induced by STM tip

    Energy Technology Data Exchange (ETDEWEB)

    Kishida, M. [Department of Electronic Engineering, Faculty of Engineering, Osaka University, Suita, Osaka 565-0871 (Japan)]. E-mail: kishida@ele.eng.osaka-u.ac.jp; Saranin, A.A. [Department of Electronic Engineering, Faculty of Engineering, Osaka University, Suita, Osaka 565-0871 (Japan); Institute of Automation and Control Processes, 690041 Vladivostok (Russian Federation); Faculty of Physics and Engineering, Far Eastern State University, 690000 Vladivostok (Russian Federation); Zotov, A.V. [Faculty of Physics and Engineering, Far Eastern State University, 690000 Vladivostok (Russian Federation); Kotlyar, V.G. [Institute of Automation and Control Processes, 690041 Vladivostok (Russian Federation); Nishida, A. [Department of Electronic Engineering, Faculty of Engineering, Osaka University, Suita, Osaka 565-0871 (Japan); Murata, Y. [Department of Electronic Engineering, Faculty of Engineering, Osaka University, Suita, Osaka 565-0871 (Japan); Okado, H. [Department of Electronic Engineering, Faculty of Engineering, Osaka University, Suita, Osaka 565-0871 (Japan); Katayama, M. [Department of Electronic Engineering, Faculty of Engineering, Osaka University, Suita, Osaka 565-0871 (Japan); Oura, K. [Department of Electronic Engineering, Faculty of Engineering, Osaka University, Suita, Osaka 565-0871 (Japan)

    2004-10-15

    Formation of the thallium (Tl) overlayers on the Si(1-bar 0-bar 0) 2x1 surface has been studied using scanning tunneling microscopy (STM). It has been found that adsorption of Tl atom involves a charge transfer leading to the development of a static dipole which is responsible for the field-assisted migration of the Tl adsorbate on the surface. When the STM tip bias voltage is positive, Tl atoms are repelled out from the region underneath the tip apex. In the case of the negative bias voltage, Tl is accumulated underneath the tip. Thus, the observed structure of the surface is controlled not only by Tl coverage, but also by the STM bias voltage and tunneling current.

  8. Virtual and Dynamic Hierarchical Architecture:an overlay network topology for discovering grid services with high performance

    Institute of Scientific and Technical Information of China (English)

    黄理灿; 吴朝晖; 潘云鹤

    2004-01-01

    This paper presents an overlay network topology called Virtual and Dynamic Hierarchical Architecture (VDHA) for discovering Grid services with high performance. Service discovery based on VDHA has scalable, autonomous, efficient, reliable and quick responsive. We propose two service discovery algorithms. Full Search Query and Discovery Protocol (FSQDP) discovers the nodes that match the request message from all N nodes, which has time complexity O(logN), space complexity O(nvg) (nvg being node numbers of each virtual group), and message-cost O(N), and Domain-Specific Query and Discovery Protocol (DSQDP) searches nodes in only specific domains with time complexity O(nvg), space complexity O(nvg), and message-cost O(nvg). In this paper, we also describe VDHA, its formal definition, and Grid Group Management Protocol.

  9. APPLICATION OF THE OVERLAY WEIGHTED MODEL AND BOOLEAN LOGIC TO DETERMINE THE BEST LOCATIONS FOR ARTIFICIAL RECHARGE OF GROUNDWATER

    Directory of Open Access Journals (Sweden)

    Peter H.S. Riad

    2011-01-01

    Full Text Available With population increase, lack of conventional fresh water resources and uncertainties due to climate change, there is growing interest in the arid and semi-arid areas to increase groundwater recharge with recycled water. Finding the best locations for artificial recharge of groundwater in such areas is one of the most crucial design steps to guarantee the long life and the sustainability of these projects. This study presents two ways to go about performing analysis; creating a suitability map to find out the suitability of every location on the map and another way is querying the created data sets to obtain a Boolean result of true or false map. These techniques have been applied on Sadat Industrial City which is located in a semi arid area in the western desert fringes of The Nile delta in the north west of Egypt. Thematic layers for number of parameters were prepared from some maps and satellite images and they have been classified, weighted and integrated in ArcGIS environment. By the means of the overlay weighted model in ArcGIS a suitability map which is classified into number of priority zones was obtained and it could be compared with the obtained true-false map of Boolean logic. Both methods suggested mostly the northern parts of the city for groundwater recharge; however the weighted model could give more accurate suitability map while Boolean logic suggested wider ranges of areas. This study recommends Boolean logic as a first estimator for locating the best locations as it is easier and not time consuming, while the overlay weighted model for more accurate results.

  10. APPLICATION OF THE OVERLAY WEIGHTED MODEL AND BOOLEAN LOGIC TO DETERMINE THE BEST LOCATIONS FOR ARTIFICIAL RECHARGE OF GROUNDWATER

    Directory of Open Access Journals (Sweden)

    Max Billib

    2011-12-01

    Full Text Available With population increase, lack of conventional fresh water resources and uncertainties due to climate change, there is growing interest in the arid and semi-arid areas to increase groundwater recharge with recycled water. Finding the best locations for artificial recharge of groundwater in such areas is one of the most crucial design steps to guarantee the long life and the sustainability of these projects. This study presents two ways to go about performing analysis; creating a suitability map to find out the suitability of every location on the map and another way is querying the created data sets to obtain a Boolean result of true or false map. These techniques have been applied on Sadat Industrial City which is located in a semi arid area in the western desert fringes of The Nile delta in the north west of Egypt. Thematic layers for number of parameters were prepared from some maps and satellite images and they have been classified, weighted and integrated in ArcGIS environment. By the means of the overlay weighted model in ArcGIS a suitability map which is classified into number of priority zones was obtained and it could be compared with the obtained true-false map of Boolean logic. Both methods suggested mostly the northern parts of the city for groundwater recharge; however the weighted model could give more accurate suitability map while Boolean logic suggested wider ranges of areas. This study recommends Boolean logic as a first estimator for locating the best locations as it is easier and not time consuming, while the overlay weighted model for more accurate results.

  11. Improved antifouling properties and selective biofunctionalization of stainless steel by employing heterobifunctional silane-polyethylene glycol overlayers and avidin-biotin technology

    Science.gov (United States)

    Hynninen, Ville; Vuori, Leena; Hannula, Markku; Tapio, Kosti; Lahtonen, Kimmo; Isoniemi, Tommi; Lehtonen, Elina; Hirsimäki, Mika; Toppari, J. Jussi; Valden, Mika; Hytönen, Vesa P.

    2016-01-01

    A straightforward solution-based method to modify the biofunctionality of stainless steel (SS) using heterobifunctional silane-polyethylene glycol (silane-PEG) overlayers is reported. Reduced nonspecific biofouling of both proteins and bacteria onto SS and further selective biofunctionalization of the modified surface were achieved. According to photoelectron spectroscopy analyses, the silane-PEGs formed less than 10 Å thick overlayers with close to 90% surface coverage and reproducible chemical compositions. Consequently, the surfaces also became more hydrophilic, and the observed non-specific biofouling of proteins was reduced by approximately 70%. In addition, the attachment of E. coli was reduced by more than 65%. Moreover, the potential of the overlayer to be further modified was demonstrated by successfully coupling biotinylated alkaline phosphatase (bAP) to a silane-PEG-biotin overlayer via avidin-biotin bridges. The activity of the immobilized enzyme was shown to be well preserved without compromising the achieved antifouling properties. Overall, the simple solution-based approach enables the tailoring of SS to enhance its activity for biomedical and biotechnological applications. PMID:27381834

  12. Comparing the capitalisation benefits of light-rail transit and overlay zoning for single-family houses and condos by neighbourhood type in metropolitan Phoenix, Arizona.

    Science.gov (United States)

    Atkinson-Palombo, Carol

    2010-01-01

    Light rail transit (LRT) is increasingly accompanied by overlay zoning which specifies the density and type of future development to encourage landscapes conducive to transit use. Neighbourhood type (based on land use mix) is used to partition data and investigate how pre-existing land use, treatment with a park-and-ride (PAR) versus walk-and-ride (WAR) station and overlay zoning interrelate. Hedonic models estimate capitalisation effects of LRT-related accessibility and overlay zoning on single-family houses and condos in different neighbourhoods for the system in metropolitan Phoenix, Arizona. Impacts differ by housing and neighbourhood type. Amenity-dominated mixed-use neighbourhoods-predominantly WAR communities-experience premiums of 6 per cent for single-family houses and over 20 per cent for condos, the latter boosted an additional 37 per cent by overlay zoning. Residential neighbourhoods-predominantly PAR communities-experience no capitalisation benefits for single-family houses and a discount for condos. The results suggest that land use mix is an important variable to select comparable neighbourhoods.

  13. Thickness-dependent relaxation of NiO(001) overlayers on MgO(001) studied by X-ray diffraction

    NARCIS (Netherlands)

    James, MA; Hibma, T

    1999-01-01

    Under equilibrium conditions, coherent growth on a substrate having the same crystal structure as the overlayer will break down above a critical thickness as a result of the stable formation of misfit dislocations. In practice, however, owing to the existence of kinetic barriers, much thicker cohere

  14. Scopus and Web-of-Science 2012 compared in terms of aggregated journal-journal citation relations: Global maps and interactive overlays

    NARCIS (Netherlands)

    Leydesdorff, L.; de Moya-Anegón, F.; de Nooy, W.; Noyons, E.

    2014-01-01

    We compare the networks of aggregated journal-journal citation relations as provided by the Journal Citation Reports (JCR) 2012 of the Science and Social Science Citation Indexes (SCI and SSCI) with similar data for 2012 based on Scopus. First, we develop basemaps and overlays for the two sets separ

  15. Improved antifouling properties and selective biofunctionalization of stainless steel by employing heterobifunctional silane-polyethylene glycol overlayers and avidin-biotin technology

    Science.gov (United States)

    Hynninen, Ville; Vuori, Leena; Hannula, Markku; Tapio, Kosti; Lahtonen, Kimmo; Isoniemi, Tommi; Lehtonen, Elina; Hirsimäki, Mika; Toppari, J. Jussi; Valden, Mika; Hytönen, Vesa P.

    2016-07-01

    A straightforward solution-based method to modify the biofunctionality of stainless steel (SS) using heterobifunctional silane-polyethylene glycol (silane-PEG) overlayers is reported. Reduced nonspecific biofouling of both proteins and bacteria onto SS and further selective biofunctionalization of the modified surface were achieved. According to photoelectron spectroscopy analyses, the silane-PEGs formed less than 10 Å thick overlayers with close to 90% surface coverage and reproducible chemical compositions. Consequently, the surfaces also became more hydrophilic, and the observed non-specific biofouling of proteins was reduced by approximately 70%. In addition, the attachment of E. coli was reduced by more than 65%. Moreover, the potential of the overlayer to be further modified was demonstrated by successfully coupling biotinylated alkaline phosphatase (bAP) to a silane-PEG-biotin overlayer via avidin-biotin bridges. The activity of the immobilized enzyme was shown to be well preserved without compromising the achieved antifouling properties. Overall, the simple solution-based approach enables the tailoring of SS to enhance its activity for biomedical and biotechnological applications.

  16. The effect of a fiber reinforced cavity configuration on load bearing capacity and failure mode of endodontically treated molars restored with CAD/CAM resin composite overlay restorations

    NARCIS (Netherlands)

    Rocca, G.T.; Saratti, C.M.; Cattani-Lorente, M.; Feilzer, A.J.; Scherrer, S.; Krecji, I.

    2015-01-01

    Objectives To evaluate the fracture strength and the mode of failure of endodontically treated molars restored with CAD/CAM overlays with fiber reinforced composite build-up of the pulp chamber. Methods 40 Devitalized molars were cut over the CEJ and divided into five groups (n = 8). The pulp chambe

  17. 具有小世界特性的语义覆盖网络模型%Semantic Overlay Network Model with Small-world Features

    Institute of Scientific and Technical Information of China (English)

    刘浩; 贺文华

    2012-01-01

    The topology structure of P2P overlay network decides its system performance. However, the existing P2P overlay network models do not take clustering and symmetry of nodes into account, and support only precise resource locating scheme. A Semantic Overlay Network(SON) model with small-world features is proposed in the paper. It adopts the mechanism of distinctly grouping, semantic search edge and Group Flooding(GF). Results of analysis and experiment show that this model provides better network performance and higher search efficiency than the existing overlay network models such as Chord and CAN. Furthermore, it has the querying capability of multi-matching results.%目前大多数的结构化覆盖网络模型忽略节点的聚类性和对称性,并且只能提供精确的资源查询机制.为此,给出一种具有小世界特性的语义覆盖网络模型.该模型采用显式分区机制、语义搜索链和组扩散机制.分析和实验结果表明,该模型比现有的覆盖网络模型Chord和CAN具有更好的网络性能,搜索效率更高,且具有较好的多匹配结果查询能力.

  18. Thermal relaxation of bituminous coal to improve donation ability of hydrogen radicals in flash pyrolysis; Sekitan kozo kanwa ni yoru suiso radical kyoyo noryoku no kojo wo mezashita netsubunkai mae shori

    Energy Technology Data Exchange (ETDEWEB)

    Mori, T.; Isoda, T.; Kusakabe, K.; Morooka, S. [Kyushu University, Fukuoka (Japan). Faculty of Engineering; Hayashi, J. [Hokkaido University, Sapporo (Japan). Center for Advanced Research of Energy Technology

    1996-10-28

    In terms of coal conversion reaction, the behavior of bituminous coal heated beyond a glass transition point was examined on the basis of pyrolyzed products, and the effect of an increase in proton mobility on promotion of coal decomposition was evaluated. In experiment, after Illinois bituminous coal specimen was heated up to a specific temperature in N2 or He gas flow at a rate of 5K/min, the specimen was directly transferred to a pyrolyzer for instantaneous pyrolysis. As the experimental result, the glass transition temperature of the Illinois coal specimen was calculated to be 589K from a differential scanning calorimetry (DSC) profile. From the pyrolysis result of the Illinois coal specimen heated up to 623K, the char yield decreased by 3kg as compared with that of the original coal, while the tar yield increased by 4kg up to 27kg per 100kg of the original coal. This tar increase was larger than that of cooled coal. These results suggested that the donation of hydrogen radicals to coal fragments is improved with an increase in proton mobility. 4 refs., 4 figs., 1 tab.

  19. Study of stabilization/solidification processes (of solid porous wastes) based on hydraulic or bituminous binders; Etude des procedes de stabilisation/solidification (des dechets solides poreux) a base de liants hydrauliques ou de liants bitumineux

    Energy Technology Data Exchange (ETDEWEB)

    Sing-Teniere, Ch.

    1998-02-01

    The first part of this thesis presents the regulatory framework and the technical context linked with the study of stabilized/solidified wastes and with the evaluation of stabilization/solidification processes. A presentation of the two type of ultimate wastes under study (a used catalyst and an activated charcoal) and an analysis of the processes is given. The second part is devoted to the experimental characterization of both types of porous wastes. The third part deals with the processing of such wastes using an hydraulic binder. The study stresses on both on the stabilization/solidification efficiency of the process and on the conditions of its implementation. The same work is made for a process that uses a bituminous binder. Some choice criteria for the selection of the better process are deduced from the examination of the overall data collected. The waste characterization methodology is applied six times: two times for the raw wastes, two times for the same wastes processed with an hydraulic binder, and two times for the same wastes processed with a bituminous binder. (J.S.)

  20. Microsegregation and Precipitates in Inconel 625 Arc Weld Overlay Coatings on Boiler Pipes / Mikrosegregacja I Wydzielenia W Powłokach Ze Stopu Inconel 625 Napawanych Łukowo Na Rury Kotłowe

    Directory of Open Access Journals (Sweden)

    Rozmus-Górnikowska M.

    2015-12-01

    Full Text Available The aim of this work was to investigate the microsegregation and precipitates formed due to segregation in Inconel 625 arc weld overlay coatings on boiler pipes. Examination of microsegregation and precipitates were carried out by means of a scanning electron microscope (SEM equipped with an EDS detector as well as a transmission electron microscope (TEM equipped with a HAADF (STEM and an EDS detectors. The presence of precipitations in the weld overlay was also confirmed with X-ray diffraction analysis (XRD of residue in the form of powder that remained after the electrolytic dissolution of weld overlay matrix.