Bibliografias temáticas / Dbrl

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Literatura científica selecionada sobre o tema "Dbrl"

Autor: Grafiati

Publicado: 25 de julho de 2024

Última modificação: 31 de julho de 2024

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Artigos de revistas sobre o assunto "Dbrl"

Özer, Ömer. "Investigation of Strength, Flexibility and Balance Parameters with Performance Dimension in Basketball Players". Journal of Education and Learning 8, n.º 5 (20 de setembro de 2019): 225. http://dx.doi.org/10.5539/jel.v8n5p225.

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The aim of this study is to investigate the relationship between strength, flexibility and balance parameters of male basketball players with performance dimension. Sixteen elite basketball players participated in the study voluntarily. Leg and back strength, flexibility and static and dynamic balance parameters of the participants were examined. Pearson Product Moment Correlation Coefficient method was used to determine the relationship between performance values obtained from strength, flexibility and balance parameters. As a result of the analysis of the data obtained; between LS and BS (r = 0.676 p < 0.01), SBRL and SBB (r = 0.787 p < 0.01), SBLL and SBB and SBRL (r = 0.688 p < 0.01, r = 0.791 p < 0.01), DBB and SBB and SBRL (r = 0.775 p < 0.01, r = 0.752 p < 0.01), DBRL and SBB, SBRL, SBLL and DBB (r = 0.800 p < 0.01, r = 0.694 p < 0.01, r = 0.707 p < 0.01, r = 0.874 p < 0.01), DBLL and SBB and SBRL (r = 0.765 p < 0.01, r = 0.652 p < 0.01) are high related. Whiler there was a moderate relationship between DBB and SBLL(r = 0.610 p < 0.05), DBRL and SBRL, DBB and DBRL (r = 0.588 p < 0.05, r = 0.589 p < 0.05, r = 0.566 p < 0.05), there were no relationship between FLX and LS and BS(r = 0.430 p > 0.05, r = 0.155 p > 0.05), SDİ SBB and LS, BS and FLX (r = 0.341 p > 0.05, r = 0.388 p > 0.05, r = 0.274 p > Z0.05), SDSA SBRL and LS, BS and FLX (r = 0.103 p > 0.05, r = 0.347 p > 0.05, r = 0.167 p > 0.05), SBLL and LS, BS ve FLX (r = -0.027 p > 0.05, r = 0.237 p > 0.05, r = 0.022 p > 0.05), DBB and LS, BS ve FLX (r = 0.211 p > 0.05, r = 0.306 p > 0.05, r = 0.268 p > 0.05), DBRL and LS, BS and FLX (r = 0.268 p > 0.05, r = 0.433 p > 0.05, r = 0.281 p > 0.05), DBLL and LS, BS and FLX (r = 0.136 p > 0.05, r = 0.137 p > 0.05, r = 0.164 p > 0.05). As a result, it is thought that the basketball players’ performance will be increased by paying attention to the content of training programs due to the sudden direction change actions of basketball, which are related to strength, flexibility and balance parameters of male basketball players.

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Yu, Jiabao, Jiawei Chen, Ying Chen, Zhiguo Zhou e Junwei Duan. "Double Broad Reinforcement Learning Based on Hindsight Experience Replay for Collision Avoidance of Unmanned Surface Vehicles". Journal of Marine Science and Engineering 10, n.º 12 (18 de dezembro de 2022): 2026. http://dx.doi.org/10.3390/jmse10122026.

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Although broad reinforcement learning (BRL) provides a more intelligent autonomous decision-making method for the collision avoidance problem of unmanned surface vehicles (USVs), the algorithm still has the problem of over-estimation and has difficulty converging quickly due to the sparse reward problem in a large area of sea. To overcome the dilemma, we propose a double broad reinforcement learning based on hindsight experience replay (DBRL-HER) for the collision avoidance system of USVs to improve the efficiency and accuracy of decision-making. The algorithm decouples the two steps of target action selection and target Q value calculation to form the double broad reinforcement learning method and then adopts hindsight experience replay to allow the agent to learn from the experience of failure in order to greatly improve the sample utilization efficiency. Through training in a grid environment, the collision avoidance success rate of the proposed algorithm was found to be 31.9 percentage points higher than that in the deep Q network (DQN) and 24.4 percentage points higher than that in BRL. A Unity 3D simulation platform with high fidelity was also designed to simulate the movement of USVs. An experiment on the platform fully verified the effectiveness of the proposed algorithm.

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Yang, Yibin, Lingxia Zhang e Yu Zhao. "Light Output Enhancement of GaN-Based Light-Emitting Diodes Based on AlN/GaN Distributed Bragg Reflectors Grown on Si (111) Substrates". Crystals 10, n.º 9 (1 de setembro de 2020): 772. http://dx.doi.org/10.3390/cryst10090772.

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Due to the absorption of opaque Si substrates, the luminous efficiency of GaN-based light-emitting diodes (LEDs) on Si substrates is not high. So, in this work, we insert AlN/GaN distributed Bragg reflectors (DBRs) to improve the light output of GaN-based LEDs on Si (111) substrates grown via metal organic chemical vapor deposition (MOCVD). In order to obtain the highest reflectivity of the AlN/GaN DBR stop band, the growth parameters of AlN/GaN DBRs are optimized, including the growth temperature, the V/III ratio and the growth pressure. As a consequence, the interfaces of the optimal 9-pair AlN/GaN DBRs become abrupt, and the reflectivity of the DBR stop band is as high as 85.2%, near to the calculated value (92.5%). Finally, crack-free GaN-based LEDs with 5-pair AlN/GaN DBRs are grown on Si (111) substrates. The light output of the DBR-based LED is evidently enhanced by 41.8% at the injection current of 350 mA, compared with the conventional DBR-based LED without DBRs. These results pave the way for the luminous efficiency improvement of future green and red GaN-based LEDs grown on Si substrates.

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Zhang, Cheng, Rami ElAfandy e Jung Han. "Distributed Bragg Reflectors for GaN-Based Vertical-Cavity Surface-Emitting Lasers". Applied Sciences 9, n.º 8 (17 de abril de 2019): 1593. http://dx.doi.org/10.3390/app9081593.

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A distributed Bragg reflector (DBR) is a key building block in the formation of semiconductor microcavities and vertical cavity surface emitting lasers (VCSELs). The success in epitaxial GaAs DBR mirrors paved the way for the ubiquitous deployment of III-V VCSELs in communication and mobile applications. However, a similar development of GaN-based blue VCSELs has been hindered by challenges in preparing DBRs that are mass producible. In this article, we provide a review of the history and current status of forming DBRs for GaN VCSELs. In general, the preparation of DBRs requires an optimization of epitaxy/fabrication processes, together with trading off parameters in optical, electrical, and thermal properties. The effort of epitaxial DBRs commenced in the 1990s and has evolved from using AlGaN, AlN, to using lattice-matched AlInN with GaN for DBRs. In parallel, dielectric DBRs have been studied since 2000 and have gone through a few design variations including epitaxial lateral overgrowth (ELO) and vertical external cavity surface emitting lasers (VECSEL). A recent trend is the use of selective etching to incorporate airgap or nanoporous GaN as low-index media in an epitaxial GaN DBR structure. The nanoporous GaN DBR represents an offshoot from the traditional epitaxial approach and may provide the needed flexibility in forming manufacturable GaN VCSELs. The trade-offs and limitations of each approach are also presented.

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Al-Dulaijan, Yousif A., e Abdulrahman A. Balhaddad. "Prospects on Tuning Bioactive and Antimicrobial Denture Base Resin Materials: A Narrative Review". Polymers 15, n.º 1 (23 de dezembro de 2022): 54. http://dx.doi.org/10.3390/polym15010054.

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Denture base resin (DBR) materials are used in dentistry in constructing removable dentures and implant-supported prostheses. A plethora of evidence has demonstrated that DBR materials are associated with a high risk of denture stomatitis, a clinical complication where the soft oral tissues underneath the resin-based material are inflamed. The prevalence of denture stomatitis among denture wearers is high worldwide. Plaque accumulation and the infiltration of oral microbes into DBRs are among the main risk factors for denture stomatitis. The attachment of fungal species, mainly Candida albicans, to DBRs can irritate the underneath soft tissues, leading to the onset of the disease. As a result, several attempts were achieved to functionalize antimicrobial compounds and particles into DBRs to prevent microbial attachment. This review article explored the advanced approaches in designing bioactive and antimicrobial DBR materials. It was reported that using monomer mixtures, quaternary ammonium compounds (QACs), and organic and inorganic particles can suppress the growth of denture stomatitis-related pathogens. This paper also highlighted the importance of characterizing bioactive DBRs to be mechanically and physically sustainable. Future directions may implement a clinical translational model to attempt these materials inside the oral cavity.

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Breiland, W. G., A. A. Allerman, J. F. Klem e K. E. Waldrip. "Distributed Bragg Reflectors for Vertical-Cavity Surface-Emitting Lasers". MRS Bulletin 27, n.º 7 (julho de 2002): 520–24. http://dx.doi.org/10.1557/mrs2002.170.

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AbstractDistributed Bragg reflectors (DBRs) not only serve as high-reflectance mirrors to define the laser cavity of a vertical-cavity surface-emitting laser (VCSEL), but they also must conduct electricity, confine currents, and provide a single-crystal template for the gain region of the laser. Basic optical and electrical properties of DBRs are presented in this article. Three examples of DBR structures used in VCSEL applications from the ultraviolet to the infrared are given to illustrate the complexity and range of materials science issues that are encountered in DBR growth. Fabrication issues are also discussed.

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Abubaker, Shawbo A. "A Comparison of Top Distributed Bragg Reflector for 1300 nm Vertical Cavity Semiconductor Optical Amplifiers Based on III–V Compound". ARO-THE SCIENTIFIC JOURNAL OF KOYA UNIVERSITY 9, n.º 2 (28 de outubro de 2021): 26–29. http://dx.doi.org/10.14500/aro.10846.

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In this work, the design of GaAs/AlGaAs distributed Bragg reflector (DBR) has been implemented for 1300 nm vertical cavity semiconductor optical amplifiers (VCSOAs) for optical fiber communication applications. The top DBR period and Al concentration are varied, the peak reflectivity of the DBR is increasing from 50% to 97.5% for 13 periods with increasing Al concentration, whereas the reflectivity bandwidth is increased to almost 190 nm. The relation between wavelength and incidence angle variation on DBR reflectivity is increasing with the incident angle (0°, 20°, 30°, and 50°), the resonant wavelength and bandwidth of the measured reflectance spectra shifts to shorter wavelength and wider bandwidth, respectively. In addition, a comparison between the linear, the graded, and the parabolic DBRs has been achieved with transfer matrix method using MATLAB software to show the influence of layer in DBRs and its effect on lasing wavelength. It is shown that using grading DBR mirror is much more beneficial compared to abrupt DBR, whereas it has lower reflectivity of almost 10% due to VCSOAs device which needs less number of top layers until prevent reaching lasing threshold.

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Lu, Xingdong, Jing Li, Kang Su, Chang Ge, Zhicong Li, Teng Zhan, Guohong Wang e Jinmin Li. "Performance-Enhanced 365 nm UV LEDs with Electrochemically Etched Nanoporous AlGaN Distributed Bragg Reflectors". Nanomaterials 9, n.º 6 (6 de junho de 2019): 862. http://dx.doi.org/10.3390/nano9060862.

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A 365-nm UV LED was fabricated based on embedded nanoporous AlGaN distributed Bragg reflectors (DBR) by electrochemical etching. The porous DBR had a reflectance of 93.5% at the central wavelength of 365 nm; this is the highest value of porous AlGaN DBRs below 370 nm which has been reported so far. An innovative two-step etching method with a SiO2 sidewall protection layer (SPL) was proposed to protect the n-AlGaN layer and active region of UV LED from being etched by the electrolyte. The DBR-LED with SPL showed 54.3% improvement of maximal external quantum efficiency (EQE) and 65.7% enhancement of optical power at 100 mA without any degeneration in electrical properties, compared with the un-etched standard LED sample. This work has paved the way for the application of electrically-pumped UV LEDs and VCSELs based on nanoporous AlGaN DBRs.

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Wang, Qi, Hai Na Mo, Zi Qiao Lou, Ke Meng Yang, Yue Sun, Yuan Jun He e De Yuan Chen. "Effects of One-Dimensional Photonic Crystal on Thin Film Silicon Solar Cells". Advanced Materials Research 827 (outubro de 2013): 49–53. http://dx.doi.org/10.4028/www.scientific.net/amr.827.49.

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We have designed lateral contact thin film silicon-based solar cells with and without one-dimensional photonic crystals as back surface field layer. The photonic crystal comprises a distributed Bragg reflector (DBR) for trapping the light. Simulations demonstrate that energy conversion efficiency and short circuit current ISCfor c-Si solar cells with the photonic crystal structure are increased to 21.11% and 27.0 mA, respectively, from 18.33% and 22.8mA of the one without photonic crystal. In addition, the effects of DBRs consisting of different materials are investigated in our simulations. When the refractive index difference between sub-layers of the DBR is larger, the forbidden band width is broader, the reflectance of the DBR is higher, and more photons are reflected and trapped into the active region, then the absorption efficiency and the energy conversion efficiency of the solar cell are both increased. The bigger the refractive index difference of the DBRs sub-layers is, the broader the forbidden band width is. In addition, a-Si solar cells with and without DBR are also discussed.

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Hamaguchi, Tatsushi, Hiroshi Nakajima e Noriyuki Fuutagawa. "GaN-based Vertical-Cavity Surface-Emitting Lasers Incorporating Dielectric Distributed Bragg Reflectors". Applied Sciences 9, n.º 4 (20 de fevereiro de 2019): 733. http://dx.doi.org/10.3390/app9040733.

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This paper reviews past research and the current state-of-the-art concerning gallium nitride-based vertical-cavity surface-emitting lasers (GaN-VCSELs) incorporating distributed Bragg reflectors (DBRs). This paper reviews structures developed during the early stages of research into these devices, covering both major categories of GaN-based VCSELs: hybrid-DBR and all-dielectric-DBR. Although both types exhibited satisfactory performance during continuous-wave (CW) operation in conjunction with current injection as early as 2008, GaN-VCSELs have not yet been mass produced for several reasons. These include the difficulty in controlling the thicknesses of nitride semiconductor layers in hybrid-DBR type devices and issues related to the cavity dimensions in all-dielectric-DBR units. Two novel all-dielectric GaN-based VCSEL concepts based on different structures are examined herein. In one, the device incorporates dielectric DBRs at both ends of the cavity, with one DBR embedded in n-type GaN grown using the epitaxial lateral overgrowth technique. The other concept incorporates a curved mirror fabricated on (000-1) GaN. Both designs are intended to mitigate challenges regarding industrial-scale processing that are related to the difficulty in controlling the cavity length, which have thus far prevented practical applications of all-dielectric GaN-based VCSELs.

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Teses / dissertações sobre o assunto "Dbrl"

Sherwood, Nicholas. "An IPsec Compatible Implementation of DBRA and IP-ABR". Digital WPI, 2005. https://digitalcommons.wpi.edu/etd-theses/738.

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Satellites are some of the most difficult links to exploit in a Quality of Service (QoS) sensitive network, largely due to their high latency, variable-bandwidth and low-bandwidth nature. Central management of shared links has been shown to provide efficiency gains and enhanced QoS by effectively allocating resources according to reservations and dynamic resource availability. In a modern network, segregated by secure gateways and tunnels such as provided by IPsec, central management appears impossible to implement due to the barriers created between a global Dynamic Bandwidth Resource Allocation (DBRA) system and the mediators controlling the individual flows. This thesis explores and evaluates various through-IPsec communications techniques aimed at providing a satellite-to-network control channel, while maintaining data security for all communications involved.

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Bohlen, Brandon Scott. "PECVD grown DBR for microcavity OLED sensor". [Ames, Iowa : Iowa State University], 2007.

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Horowitz, Luke. "Adaptation of VT-Dbr Lasers for LIDAR". DigitalCommons@CalPoly, 2018. https://digitalcommons.calpoly.edu/theses/1902.

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Vernier Tuned Distributed Bragg Reflector (VT-DBR) lasers have had great success in the field of Swept-Source Optical Coherence Tomography (SS-OCT) due to their continuous and nearly 40 nm wavelength tuning range in a single longitudinal mode. Fast sweeps allow for real time imaging with micrometer resolution at a distance of a few centimeters. While this laser has proven quite useful as a medical imaging tool via OCT, it has yet to similarly prove itself for general light detection and ranging (LIDAR) applications due to range limitations that arise from a finite laser coherence length. The goal of this thesis is to explore LIDAR applications for VT-DBR lasers and how to improve VT-DBR performance for LIDAR. In the scope of this work, LIDAR is laser imaging at tens or hundreds of meters with a resolution finer than 10cm. In order to achieve this kind of LIDAR performance with a VT-DBR laser, the laser must have a linewidth less than 1MHz over a tuning range of around 10GHz. This thesis outlines two methods towards this goal. The bulk of this work is dedicated to looking for and characterizing VT-DBR tuning paths with fundamentally narrow linewidth using microampere currents in both forward and reverse bias conditions. The second part of this thesis is a preliminary design of an optical frequency-locked loop to reduce laser phase noise, which subsequently reduces the laser linewidth. By tuning with small currents in the forward bias condition, nearly the entire range of laser wavelengths could be tuned to, but areas of narrow linewidth were both sparse and very sensitive to any change in bias. The reverse bias case showed limited but continuous tuning with increased reverse current magnitude. In this reverse biased photo-detector mode the laser exhibited narrower linewidth less than 15MHz, with the linewidth at intrinsically narrow levels when all three sections reverse biased. Also promising was a subset of reverse bias conditions that only used a variable resistance across a laser section with no externally applied bias. This resistance tuning method gave a tuning range of more than 7GHz while maintaining an intrinsically narrow linewidth. The optical frequency-locked loop was able to achieve DC frequency locking but unable to reduce laser linewidth. More work needs to be done to achieve enough phase noise reduction to see an appreciable reduction in linewidth.

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Hett, Anne. "Studies on the metabolism of retained and excised introns in human cells". Thesis, University of Edinburgh, 2014. http://hdl.handle.net/1842/10515.

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In eukaryotes the coding regions of most genes are interrupted by introns that must be removed by splicing to form a coding mRNA. However, while the splicing mechanism has received a lot of attention, much less is known about the metabolism of introns. This is partly due to the difficulties in studying introns as both aberrantly spliced transcripts and spliced introns are rapidly degraded. In this study, I have analysed intron metabolism in two respects: first I have investigated how introns are degraded following the completion of splicing. Second, I investigate the fate of transcripts, in which introns are retained due to splicing failure. In order to study the degradation of introns following splicing, I performed siRNA mediated knock down of the debrancing enzyme (Dbr1). Following splicing, introns are present in a circular lariat structure and Dbr1 is the enzyme thought to be responsible for opening this. Indeed, I found that knockdown of Dbr1 increased the amount of stabilised introns. Interestingly, introns were found to be stabilised in the cytoplasm and not in the nucleus as expected, even though immunofluoresence showed that Dbr1 is clearly nuclear. However, western blot analysis localised Dbr1 in the cytoplasm. Further investigation showed widely used methods to separate nuclear and cytoplasmic fractions are prone to generating artefacts which result in nucleoplasmic proteins delocalised to the cytoplasm. This finding may prevent future misinterpretation of data obtained by these methods. To investigate splicing failure, it was necessary to generated a sufficiently large pool of unspliced transcripts. To do this I used antisense morpholinos (AMOs) that bind to specific snRNAs (small nuclear RNAs). They are designed to block interaction surfaces that are important for splicing. Using this approach, I investigated the localisation of RNA transcripts and selected RNA processing and degradation factors in normal conditions and where splicing was inhibited. When splicing is inhibited I found splicing factors and unspliced, polyadenylated RNA localising to nuclear, splicing speckle marker SC35 positive speckles. I further discovered that for RNA to localise to nuclear speckles, polyadenylation and RNA cleavage are essential, indicating that SC-35 speckles might sequester unspliced transcripts preventing translation of potentially harmful transcripts. These transcripts remain functional however, and can be spliced where functional spliceosomes can be assembled.

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Gupta, Meghana B. "Regulation of Dbl Family Guanine Nucleotide Exchange Factors". Case Western Reserve University School of Graduate Studies / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=case1386175561.

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Fedler, Fritz. "Herstellung hochreflektierender AlGaN-AlN-DBR- und UV-VCSEL-Strukturen mittels plasmaunterstützter Molekularstrahlepitaxie". [S.l. : s.n.], 2003. http://deposit.ddb.de/cgi-bin/dokserv?idn=969335695.

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JULIO, Ricardo Emerson. "DBML: Uma Biblioteca de Gerenciamento Dinâmico de Banda para Sistemas Multirrobôs Baseado em ROS". reponame:Repositório Institucional da UNIFEI, 2015. http://repositorio.unifei.edu.br:8080/xmlui/handle/123456789/114.

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Submitted by repositorio repositorio (repositorio@unifei.edu.br) on 2015-10-09T14:25:52Z No. of bitstreams: 1 dissertacao_julio_2015.pdf: 2228477 bytes, checksum: bdb709442550bbb325854408100d347b (MD5)
Made available in DSpace on 2015-10-09T14:25:52Z (GMT). No. of bitstreams: 1 dissertacao_julio_2015.pdf: 2228477 bytes, checksum: bdb709442550bbb325854408100d347b (MD5) Previous issue date: 2015-07
A comunicação é um componente importante em sistemas multirrobôs; a performance do sistema pode ser seriamente afetada quando o número de robôs do sistema ou o número de canais de comunicação aumenta. A Biblioteca de Gerenciamento Dinâmico de Banda (DBML - Dynamic Bandwidth Management Library) foi projetada de forma a maximizar a utilização da banda em sistemas multirrobôs. O sistema desenvolvido prioriza os canais de comunicação de acordo com eventos que ocorrem no ambiente oferecendo maior largura de banda para os canais de comunicação mais prioritários. A biblioteca foi desenvolvida utilizando o ROS (Robot Operating System) de forma a separar as funcionalidades em módulos independentes que possam ser reutilizados e melhorados em trabalhos futuros. Este trabalho apresenta a biblioteca desenvolvida utilizando um problema de otimização linear e um exemplo do uso da biblioteca em uma aplicação de teleoperação onde diversas simulações foram feitas. Os resultados mostraram que o DBML atribui uma maior frequência de envio de informações para os canais de comunicação mais prioritários, permitindo assim, uma maior eficiência na execução das tarefas.

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Rupp, Stephanie. "Modellgeleitete Diagnostik bei kindlichen lexikalischen Störungen [ausgezeichnet mit dem dbl-Forschungspreis]". Idstein Schulz-Kirchner, 2005. http://d-nb.info/988054396/04.

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Pozzi, Francesca. "InAlGaAs-InP laterally coupled DBR and DFB lasers for microwave generation". Thesis, University of Glasgow, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.443408.

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Smilyanets, Sergey [Verfasser]. "Spieltheoretische Analyse eines Kampfes auf dem Ratingmarkt : Der Fall: DBRS gegen etablierte Ratingagenturen / Sergey Smilyanets". Aachen : Shaker, 2010. http://d-nb.info/1098042522/34.

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Mais fontes

Livros sobre o assunto "Dbrl"

Self, Robert W. Learning dBXL. [California?: R.W. Self, 1990.

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Beeri, Catriel, Atsushi Ohori e Dennis E. Shasha, eds. Database Programming Languages (DBPL-4). London: Springer London, 1994. http://dx.doi.org/10.1007/978-1-4471-3564-7.

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Barbara, Clifford, ed. dBXL and Quicksilver programming: Beyond dBase. Carmel, Ind: Que Corp., 1988.

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United States. Department of Labor. Wage and Hour Division. The Davis-Bacon and related acts (DBRA). Washington, DC: U.S. Dept. of Labor, Wage and Hour Division, 2009.

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Schmidt, Joachim W. The Database Programming Language DBPL: Rationale and report. Hamburg: Fachbereich fu r Informatik, Universita t Hamburg, 1992.

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Rta-mgrin-rgyal, Stag-rig. Ga re byas nas dbul por gyur ba red. Lan-gruʼu: Kan-suʼu mi rigs dpe skrun khang, 2017.

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Florian, Matthes, e Universita t Hamburg. Fachbereich fu r Informatik., eds. The Database Programming Language DBPL: User and system manual. Hamburg: Fachbereich fu r Informatik, Universita t Hamburg, 1992.

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Klu-dgaʼ, Gśen-chen. Khro bo Dbal gsas daṅ Khro bo Gtso mchog gi sgrub gźuṅ: Revelations focussing upon the wrathful Bonpo deities, Dbal-gsas and Gtso-mchog. Dolanji, Dist. Solan, H.P: Tashi Dorji, 1985.

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Center, Buddhist Digital Resource. Gsung ʼbum dbra ston ngag dbang bskal bzang bstan paʼi rgyal mtshan. Pe cin: Mi rigs dpe bskrun khang, 2009.

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Gorton, Patricia Jane. A study of waveguides and gratings for achieving 10.6m DBR. Birmingham: University of Birmingham, 1989.

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Capítulos de livros sobre o assunto "Dbrl"

Weik, Martin H. "dBrn". In Computer Science and Communications Dictionary, 365. Boston, MA: Springer US, 2000. http://dx.doi.org/10.1007/1-4020-0613-6_4444.

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Weik, Martin H. "dBrn adjusted". In Computer Science and Communications Dictionary, 365. Boston, MA: Springer US, 2000. http://dx.doi.org/10.1007/1-4020-0613-6_4445.

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Weik, Martin H. "dBr". In Computer Science and Communications Dictionary, 365. Boston, MA: Springer US, 2000. http://dx.doi.org/10.1007/1-4020-0613-6_4443.

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Weik, Martin H. "dBrn(f1 − f2)". In Computer Science and Communications Dictionary, 365. Boston, MA: Springer US, 2000. http://dx.doi.org/10.1007/1-4020-0613-6_4446.

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Weik, Martin H. "dBrn(144 line)". In Computer Science and Communications Dictionary, 366. Boston, MA: Springer US, 2000. http://dx.doi.org/10.1007/1-4020-0613-6_4449.

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Reinmann, Gabi. "Design-Based Research in der Hochschuldidaktik: Forschen für Lehrinnovationen". In Hochschulbildung: Lehre und Forschung, 269–86. Bielefeld, Germany: transcript Verlag, 2023. http://dx.doi.org/10.14361/9783839461808-015.

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Der Beitrag diskutiert, inwiefern Design-Based Research (DBR) als eine Variante von Hochschulbildungsforschung Lehrinnovationen befördern kann. Illustriert an einem idealisierten Beispiel werden die konstituierenden Merkmale von DBR beschrieben und verschiedene Wissenstypen thematisiert. Herausgearbeitet werden die besonderen Potenziale von DBR für Lehrinnovationen unter der Perspektive von Transdisziplinarität, Transformation und Transfer. Inwiefern DBR eine Allianz mit Scholarship of Teaching and Learning eingehen und damit Lehrinnovationen befördern kann, bildet den Abschluss des Textes. Ziel ist es zu zeigen, dass sich DBR als Forschungsgenre in der Hochschuldidaktik dazu eignet, Lehrinnovationen reflexiv voranzubringen und zu einer innovationsfreundlichen Lehr- und Forschungskultur beizutragen.

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Koch, Jürgen. "Anfrageoptimierung im DBPL-System". In Relationale Anfragen, 121–31. Berlin, Heidelberg: Springer Berlin Heidelberg, 1985. http://dx.doi.org/10.1007/978-3-642-70626-4_6.

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Schmidt, Joachim W., e Florian Matthes. "The rationale behind DBPL". In MFDBS 91, 389–95. Berlin, Heidelberg: Springer Berlin Heidelberg, 1991. http://dx.doi.org/10.1007/3-540-54009-1_28.

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Andrews, T. "Designing Linguistic Interfaces to an Object Database or What do C++, SQL, and Hell have in Common". In Database Programming Languages (DBPL-4), 3–8. London: Springer London, 1994. http://dx.doi.org/10.1007/978-1-4471-3564-7_1.

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Leung, Theodore W., Bharathi Subramanian, Scott L. Vandenberg, Gail Mitchell, Bennet Vance e Stanley B. Zdonik. "The AQUA Data Model and Algebra". In Database Programming Languages (DBPL-4), 157–75. London: Springer London, 1994. http://dx.doi.org/10.1007/978-1-4471-3564-7_10.

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Trabalhos de conferências sobre o assunto "Dbrl"

Paraskevopoulos, A., H. Künzel, J. Sebastian, S. Gramlich, R. Hey, B. Jenichen e J. Böttcher. "Low voltage vertical-cavity surface-emitting lasers with low resistance GaAs/AlAs mirrors using δ-doped transition layers". In The European Conference on Lasers and Electro-Optics. Washington, D.C.: Optica Publishing Group, 1994. http://dx.doi.org/10.1364/cleo_europe.1994.cwd2.

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A low series resistance is a prerequisite for achieving acceptable performance of a vertical-cavity, surface-emitting laser (VCSEL). For laser emission at λ = 900–1000 nm, the binary GaAs/AlAs combination provides the adequate material choice for the distributed Bragg reflectors (DBRs), considering the difference in refractive index and the thermal conductivity. In this case, however, the potential barriers at the heterointerfaces seriously impeded the current flow and lead to high series resistance, particularly in the p-type doped DBR structures.

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Deppe, D. G., D. L. Huffaker, H. Deng, J. Shin e Q. Deng. "Spontaneous Emission Coupling to the Lasing Mode in a Fabry-Perot Microcavity with High Contrast AlxOy/GaAs Bragg Reflectors". In Quantum Optoelectronics. Washington, D.C.: Optica Publishing Group, 1995. http://dx.doi.org/10.1364/qo.1995.qthe6.

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There has been recent interest in studies of the influence of controlled spontaneous emission on the operating characteristics of lasers and light emitting diodes. Most cavity designs used in such work can be distinguished as either planar and of the Fabry-Perot type, or as possessing additional confinement in the lateral direction. For both cavity types the mirror design based on distributed Bragg reflectors (DBRs) plays an important role. Since the actual cavity length is set by light penetration into the mirrors, both the cavity length and the mirror reflectivity are set by the DBR design, which in turn sets the lateral mode profile for the planar cavity. In this talk we will present data characterizing the operation of a Fabry-Perot microcavity laser fabricated using high contrast DBRs of AlxOy/GaAs. The mirrors are formed by the selective conversion of AlAs into AlxOy using "wet oxidation" [1], resulting in the laser structure as illustrated in Fig.1. Four AlxOy/GaAs pairs are used on both the top and bottom (substrate) sides to form the laser cavity. In the actual laser cavity the oxidized mesa as illustrated in Fig.1 is 100μm in diameter while the lasing mode area is less than 10μm, so that the laser cavity is in fact planar. The resulting lasing characteristics of this cavity with high contrast DBRs are compared with those of a similar planar cavity design which uses the more typical AlAs/GaAs Bragg reflectors. For this second laser the upper reflector consists of sixteen pairs of AlAs/GaAs while the lower reflector (substrate side) consists of twenty-four pairs of AlAs/GaAs.

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Chang-Hasnain, Connie J. "Metastructured Optics Progress and Applications". In JSAP-OSA Joint Symposia. Washington, D.C.: Optica Publishing Group, 2021. http://dx.doi.org/10.1364/jsap.2021.10a_n405_1.

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Vertical cavity surface emitting lasers (VCSELs) have long been predicted as low-cost enabling laser sources for many applications including optical communications, sensing and imaging. Traditional VCSELs use distributed Bragg reflectors (DBRs) as mirrors, which consist of many tens layers of epitaxy layers with alternating refractive indecies. Snice 2004, we develeoped a new class of planar optics has emerged using near-wavelength dielectric structures, known as high contrast metastructures (HCM). Many extraordinary properties can be designed top-down based for integrated optics on a silicon or GaAs substrate. The one-dimensional version, a single layer high index contrast near-wavelength gratings (HCG), has been used to replace the hundred-layered DBR in a VCSEL structure. In this talk, I will review recent results using HCG/HCM in device applications of VCSELs, beam-steering optical phased array, biosensor, 4-wave generation, and spatial light modulator. I will discuss inventions and advances in VCSELs that have led to recent global deployment of commercial applications including 3D sensing, LIDAR and optical coherent tomography applications. I will also discuss future prospects for advanced applications.

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Ellmers, C., F. Höhnsdorf, J. Koch, C. Agert, M. Hofmann, W. W. Hühle e W. Stolz. "Emission dynamics of a (GaIn)(NAs) vertical-cavity surface-emitting laser". In The European Conference on Lasers and Electro-Optics. Washington, D.C.: Optica Publishing Group, 1998. http://dx.doi.org/10.1364/cleo_europe.1998.cpd1.8.

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Vertical-cavity surface-emitting lasers (VCSELs) are interesting devices for applications in high speed optical fiber networks. Therefore the development of VCSEL structures for the generation of short optical pulses at emission wavelengths in the optical-fiber windows of 1.3 or 1.55 µm is important. The InGaAsP-InP material system which is most common for edge emitters in this long wavelength regime suffers from the lack of epitaxial layers with high refractive index difference. Thus an appropriate distributed Bragg Reflector (DBR) can only be obtained with a large number of mirror layers. This involves not only a high resistance in electrically pumped devices, but also increases the effective cavity length which results in slower dynamics, due to longer photon lifetimes. In contrast, GaInNAs has been demonstrated recently as a very attractive active material for the long wavelength regime. It can be grown lattice matched on GaAs and thus allows to use well established GaAs-AlAs DBRs. We have realized a microcavity laser with GaInNAs quantum wells with a high enough content of nitrogen to reach wavelengths near 1.28 µm. Here we present first results on the picosecond dynamics of a GaInNAs VCSEL-structure.

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Streubel, K., e M. Hammar. "Long Wavelength Vertical Cavity Lasers". In The European Conference on Lasers and Electro-Optics. Washington, D.C.: Optica Publishing Group, 1998. http://dx.doi.org/10.1364/cleo_europe.1998.cmh1.

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Long-wavelength Vertical Cavity Lasers (VCLs) emitting at 1300 or 1550nm are considered as promising candidates as low-cost light sources in fiber optical communication systems Despite the success of their short-wavelength counterparts, and even the demonstration of well-above room temperature continuous operation of a double-fused VCSEL at 155nm /1/, their final demand on mirror reflectivity (>99.5%), uniform current injection and exact gain-cavity tuning, is even further pronounced in the long wavelength regime. This is mainly due to excessive losses (intervalence band absorption, Auger recombination and diffraction) and a relatively small refractive index difference in the InGaAsP/InP system. To overcome these problems, several generically different designs have been presented and investigated The so far most successful approaches use at least one wafer fusion step to combine an InGaAsP active layer with one or two AlGaAs/GaAs DBRs However, such solutions are rather complex from a processing point of view, not yet demonstrated as full two-inch compatible. A more attractive design in this respect is based on the combination of an InGaAsP/InP bottom DBR and a dielectric top mirror So far such lasers have been limited to low-temperature operation /2/, but significant improvements can still be expected from a better optimized current injection scheme or improved dielectric mirror quality Alternative approaches, e g., based on GaInNAs lattice matched to GaAs as active material may also become of importance.

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Mior, Michael J. "Locomotor". In DBPL 2017: The 16th International Symposium on Database Programming Languages. New York, NY, USA: ACM, 2017. http://dx.doi.org/10.1145/3122831.3122840.

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Kato, Hiroyuki, Yasunori Ishihara e Torsten Grust. "DDO-Free XQuery". In DBPL 2017: The 16th International Symposium on Database Programming Languages. New York, NY, USA: ACM, 2017. http://dx.doi.org/10.1145/3122831.3122832.

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Hellings, Jelle, Catherine L. Pilachowski, Dirk Van Gucht, Marc Gyssens e Yuqing Wu. "From relation algebra to semi-join algebra". In DBPL 2017: The 16th International Symposium on Database Programming Languages. New York, NY, USA: ACM, 2017. http://dx.doi.org/10.1145/3122831.3122833.

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Oliveira, J. N., e H. D. Macedo. "The data cube as a typed linear algebra operator". In DBPL 2017: The 16th International Symposium on Database Programming Languages. New York, NY, USA: ACM, 2017. http://dx.doi.org/10.1145/3122831.3122834.

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Luong, Johannes, Dirk Habich e Wolfgang Lehner. "AL". In DBPL 2017: The 16th International Symposium on Database Programming Languages. New York, NY, USA: ACM, 2017. http://dx.doi.org/10.1145/3122831.3122835.

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Relatórios de organizações sobre o assunto "Dbrl"

Jay. L51710 Active Noise Silencing. Chantilly, Virginia: Pipeline Research Council International, Inc. (PRCI), janeiro de 1994. http://dx.doi.org/10.55274/r0010333.

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Many natural gas compressor stations which were previously located away from residential areas are now being encroached upon by surrounding building developments. Furthermore, an increased awareness of community noise issues has proved to be the impetus for investigating and developing more effective noise control methods and treatments for natural gas compressor facilities. This project investigates the feasibility of applying Active Noise Cancellation (ANC) to the exhaust of a large, internal-combustion reciprocating type engine. Large reciprocating internal combustion engines pose significant challenges for the noise control engineer. In the case of the engines employed at Tennessee Gas Pipeline Company Compressor Station 229, these engines radiate extremely low frequency exhaust noise into the surrounding environs. These engines produce discrete frequencies in the exhaust spectra with a particularly strong component at 26.5 Hz, which corresponds to the fundamental firing frequency (the 5.0 rotational order) of the engine; significant attenuation of the raw exhaust noise can be particularly difficult due to the sound power and spectral content. Traditional methods would necessitate a very large silencer in order to realize improved attenuation of the exhaust noise, relative to the existing silencer. Measurements were conducted at the error microphone location, at 1.0 meter from the exhaust outlet and at the property line. At a distance of 1.0 meter the WNCT integrated active / passive silencer yielded 84.5 dBA (92.3 dBL) while the original equipment silencer yielded 92.7 dBA (98.8 dBL). Band-limited (DC - 200 Hz) measurements were taken at the error microphone location; control off (WNCT passive - only): 109.8 dBL overall, 107.7 dBL 26.5 Hz component. With control on (WNCT active + passive) at the same position overall noise was 99.7 dBL with the 26.5 Hz component reading 89.1 dBL. Far-field A-weighted reductions were inconclusive due to the presence of other contributing noise sources possessing similar noise characteristics. Flow resistance measurements indicated that back pressure had been reduced by 95% relative to the original equipment silencer through the use of the integrated WNCT active / passive silencer.

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Coldren, Larry A., e Bech Mason. Improved Sampled Grating DBR Widely-Tunable 1.55 micron Lasers. Fort Belvoir, VA: Defense Technical Information Center, setembro de 1999. http://dx.doi.org/10.21236/ada369438.

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Mason, T. G., J. Barton e L. A. Coldren. Improved Sampled Grating DBR Widely-Tunable 1.55 micrometer-Lasers. Fort Belvoir, VA: Defense Technical Information Center, fevereiro de 2000. http://dx.doi.org/10.21236/ada374627.

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Coldren, Larry A., e Beck Mason. Improved Sampled Grating DBR Widely-Tunable 1.55 micrometer Lasers. Fort Belvoir, VA: Defense Technical Information Center, outubro de 1997. http://dx.doi.org/10.21236/ada330542.

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Coldren, Larry A., e Beck Mason. Improved Sampled Grating DBR Widely-Tunable 1.55z Micrometer Lasers. Fort Belvoir, VA: Defense Technical Information Center, setembro de 1998. http://dx.doi.org/10.21236/ada353524.

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Beliaev, Alex. Developing Multi-Gene CRISPRa/I Programs to Accelerate DBTL Cycles in ABF Hosts Engineered for Chemical Production - CRADA 468. Office of Scientific and Technical Information (OSTI), fevereiro de 2021. http://dx.doi.org/10.2172/1827792.

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Neyedley, K., J. J. Hanley, Z. Zajacz e M. Fayek. Accessory mineral thermobarometry, trace element chemistry, and stable O isotope systematics, Mooshla Intrusive Complex (MIC), Doyon-Bousquet-LaRonde mining camp, Abitibi greenstone belt, Québec. Natural Resources Canada/CMSS/Information Management, 2021. http://dx.doi.org/10.4095/328986.

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The Mooshla Intrusive Complex (MIC) is an Archean polyphase magmatic body located in the Doyon-Bousquet-LaRonde (DBL) mining camp of the Abitibi greenstone belt, Québec, that is spatially associated with numerous gold (Au)-rich VMS, epizonal 'intrusion-related' Au-Cu vein systems, and shear zone-hosted (orogenic?) Au deposits. To elucidate the P-T conditions of crystallization, and oxidation state of the MIC magmas, accessory minerals (zircon, rutile, titanite) have been characterized using a variety of analytical techniques (e.g., trace element thermobarometry). The resulting trace element and oxythermobarometric database for accessory minerals in the MIC represents the first examination of such parameters in an Archean magmatic complex in a world-class mineralized district. Mineral thermobarometry yields P-T constraints on accessory mineral crystallization consistent with the expected conditions of tonalite-trondhjemite-granite (TTG) magma genesis, well above peak metamorphic conditions in the DBL camp. Together with textural observations, and mineral trace element data, the P-T estimates reassert that the studied minerals are of magmatic origin and not a product of metamorphism. Oxygen fugacity constraints indicate that while the magmas are relatively oxidizing (as indicated by the presence of magmatic epidote, titanite, and anhydrite), zircon trace element systematics indicate that the magmas were not as oxidized as arc magmas in younger (post-Archean) porphyry environments. The data presented provides first constraints on the depth and other conditions of melt generation and crystallization of the MIC. The P-T estimates and qualitative fO2 constraints have significant implications for the overall model for formation (crystallization, emplacement) of the MIC and potentially related mineral deposits.

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Arney, Matthew W. Light Vehicle Obscuration Smoke System (LVOSS) Participation in the 1994 Infantry Commanders' Conference (ICC) Advanced Warfighting Exercises (AWE) at the Dismounted Battlespace Battle Laboratory (DBBL) Fort Benning, Georgia 10-11 May 1994. Fort Belvoir, VA: Defense Technical Information Center, setembro de 1995. http://dx.doi.org/10.21236/ada303086.

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Neyedley, K., J. J. Hanley, P. Mercier-Langevin e M. Fayek. Ore mineralogy, pyrite chemistry, and S isotope systematics of magmatic-hydrothermal Au mineralization associated with the Mooshla Intrusive Complex (MIC), Doyon-Bousquet-LaRonde mining camp, Abitibi greenstone belt, Québec. Natural Resources Canada/CMSS/Information Management, 2021. http://dx.doi.org/10.4095/328985.

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The Mooshla Intrusive Complex (MIC) is an Archean polyphase magmatic body located in the Doyon-Bousquet-LaRonde (DBL) mining camp of the Abitibi greenstone belt, Québec. The MIC is spatially associated with numerous gold (Au)-rich VMS, epizonal 'intrusion-related' Au-Cu vein systems, and shear zone-hosted (orogenic?) Au deposits. To elucidate genetic links between deposits and the MIC, mineralized samples from two of the epizonal 'intrusion-related' Au-Cu vein systems (Doyon and Grand Duc Au-Cu) have been characterized using a variety of analytical techniques. Preliminary results indicate gold (as electrum) from both deposits occurs relatively late in the systems as it is primarily observed along fractures in pyrite and gangue minerals. At Grand Duc gold appears to have formed syn- to post-crystallization relative to base metal sulphides (e.g. chalcopyrite, sphalerite, pyrrhotite), whereas base metal sulphides at Doyon are relatively rare. The accessory ore mineral assemblage at Doyon is relatively simple compared to Grand Duc, consisting of petzite (Ag3AuTe2), calaverite (AuTe2), and hessite (Ag2Te), while accessory ore minerals at Grand Duc are comprised of tellurobismuthite (Bi2Te3), volynskite (AgBiTe2), native Te, tsumoite (BiTe) or tetradymite (Bi2Te2S), altaite (PbTe), petzite, calaverite, and hessite. Pyrite trace element distribution maps from representative pyrite grains from Doyon and Grand Duc were collected and confirm petrographic observations that Au occurs relatively late. Pyrite from Doyon appears to have been initially trace-element poor, then became enriched in As, followed by the ore metal stage consisting of Au-Ag-Te-Bi-Pb-Cu enrichment and lastly a Co-Ni-Se(?) stage enrichment. Grand Duc pyrite is more complex with initial enrichments in Co-Se-As (Stage 1) followed by an increase in As-Co(?) concentrations (Stage 2). The ore metal stage (Stage 3) is indicated by another increase in As coupled with Au-Ag-Bi-Te-Sb-Pb-Ni-Cu-Zn-Sn-Cd-In enrichment. The final stage of pyrite growth (Stage 4) is represented by the same element assemblage as Stage 3 but at lower concentrations. Preliminary sulphur isotope data from Grand Duc indicates pyrite, pyrrhotite, and chalcopyrite all have similar delta-34S values (~1.5 � 1 permille) with no core-to-rim variations. Pyrite from Doyon has slightly higher delta-34S values (~2.5 � 1 permille) compared to Grand Duc but similarly does not show much core-to-rim variation. At Grand Duc, the occurrence of Au concentrating along the rim of pyrite grains and associated with an enrichment in As and other metals (Sb-Ag-Bi-Te) shares similarities with porphyry and epithermal deposits, and the overall metal association of Au with Te and Bi is a hallmark of other intrusion-related gold systems. The occurrence of the ore metal-rich rims on pyrite from Grand Duc could be related to fluid boiling which results in the destabilization of gold-bearing aqueous complexes. Pyrite from Doyon does not show this inferred boiling texture but shares characteristics of dissolution-reprecipitation processes, where metals in the pyrite lattice are dissolved and then reconcentrated into discrete mineral phases that commonly precipitate in voids and fractures created during pyrite dissolution.

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