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1.
Alexandre Szklo Giovani Machado Roberto Schaeffer Jacqueline Mariano Janaí na Sala Marina Tavares 《Catalysis Today》2005,106(1-4):123-128
This paper assesses the impacts of a GTL plant on the expansion of Brazil's oil refining segment. The GTL plant (50,000 bpd) was sized to start up operations in 2015, producing diesel and naphtha through the indirect route (FT-synthesis). This plant will consume the non-associated natural gas production from the recent discoveries at the Santos Basin (around 419 Bm3), and the associated gas production from the Campos Basin. Both basins are located in the Southeast of Brazil, the most populated, rich and industrialized region of the country. Two different criteria for refinery expansion were simulated in order to meet oil product demand scenarios. Findings show that depending on the refinery expansion criteria considered GTL will play a fundamental hole to meet the oil product demand forecast to Brazil in the next 10 years. 相似文献
2.
Tom Mariano 《集成电路应用》2008,(11):25-25
在近期一次SEMI产业策略论坛发表的演讲中,Lam Research Corp.的总裁兼CEO Stephen Newberry认为,半导体产业已经进入了“无利的繁荣时代”。2003年以来,每比特/功能的价格已经比每比特/价格的成本下降得更快,使得整个产业的利润遭到侵蚀。这似乎成为了一个无法维继的市场,随着时间的推移必须进行自我修正才行。 相似文献
3.
Challenged by competition pressures and unprecedented pace of change, firms can no longer choose whether to concentrate on the needs of today's customers or on the anticipation of those of tomorrow: they must be excellent in both. This requires managing two related balancing acts: on the one side, being excellent in both exploitation and exploration of their capabilities and, on the other side, being excellent in managing both incremental and radical innovation. These balances are critical since exploitation and exploration, on the one side, and incremental and radical innovation, on the other, require different approaches that have traditionally been considered difficult to combine within the same organization. Working on evidence and discussion from the 7th CINet Conference held in Lucca (Italy) in 2006, this Special Section is aimed at contributing to theory and practice on these two complex balancing acts that today represent a hot issue in innovation management. 相似文献
4.
The Journal of Supercomputing - DNA methylation analysis has become an important topic in the study of human health. DNA methylation analysis requires not only a specific treatment of DNA samples... 相似文献
5.
Yuk Ming X. Hung Hung Mariano H. Talou María A. Camerucci 《International Journal of Applied Ceramic Technology》2021,18(5):1466-1477
Alumina ceramic porous structures were shaped by the fused deposition of alumina/polyamide 612 composite granules using an FDM 3D printer with a modified extruder to process granulated powder instead of a filament. The composite granules were prepared via thermally induced phase separation (TIPS). Firstly, in order to determine the proportion of polymer/solvent to be used in the TIPS process, different volume fractions of PA612 in dimethyl sulfoxide (DMSO) were studied (0.01 to 0.20), and the granules obtained were characterized by SEM, DSC, and Raman spectroscopy. Secondly, the addition of different ceramic loadings to the PA612/DMSO solution was studied with the aim of determining the amount to be used for preparing the composite granules by TIPS. In particular, the effect of the alumina content on the morphology and size of the obtained composite granules was studied. In addition, rheological properties (oscillatory and rotational tests) of the feed materials were studied. Finally, the printing conditions, including the nozzle temperature and nozzle diameter, and the extrusion process, were optimized in order to obtain porous structures with good quality. Alumina porous structures were successfully printed, debinded, and sintered. Adequate bonding between layers was achieved, and no defects at interfaces were detected. 相似文献
6.
We present a method for foreground/background video segmentation (change detection) in real-time that can be used, in applications such as background subtraction or analysis of surveillance cameras. Our approach implements a probabilistic segmentation based on the Quadratic Markov Measure Field models. This framework regularizes the likelihood of each pixel belonging to each one of the classes (background or foreground). We propose a new likelihood that takes into account two cases: the first one is when the background is static and the foreground might be static or moving (Static Background Subtraction), the second one is when the background is unstable and the foreground is moving (Unstable Background Subtraction). Moreover, our likelihood is robust to illumination changes, cast shadows and camouflage situations. We implement a parallel version of our algorithm in CUDA using a NVIDIA Graphics Processing Unit in order to fulfill real-time execution requirements. 相似文献
7.
Emilio Soto Candela Mario Ortega Pérez Clemente Marín Romero David C. Pérez López Gustavo Salvador Herranz Manuel Contero Mariano Alcañiz Raya 《Multimedia Tools and Applications》2014,70(3):1837-1868
In this paper, a computer vision based interactive multi-touch tabletop system called HumanTop is introduced. HumanTop implements a stereo camera vision subsystem which allows not only an accurate fingertip tracking algorithm but also a precise touch-over-the-working surface detection method. Based on a pair of visible spectra cameras, a novel synchronization circuit makes the camera caption and the image projection independent from each other, providing the minimum basis for the development of computer vision analysis based on visible spectrum cameras without any interference coming from the projector. The assembly of both cameras and the synchronization circuit is not only capable of performing an ad-hoc version of a depth camera, but it also introduces the recognition and tracking of textured planar objects, even when contents are projected over them. On the other hand HumanTop supports the tracking of sheets of paper and ID-code markers. This set of features makes the HumanTop a comprehensive, intuitive and versatile augmented tabletop that provides multitouch interaction with projective augmented reality on any flat surface. As an example to exploit all the capabilities of HumanTop, an educational application has been developed using an augmented book as a launcher to different didactic contents. A pilot study in which 28 fifth graders participated is presented. Results about efficiency, usability/satisfaction and motivation are provided. These results suggest that HumanTop is an interesting platform for the development of educational contents. 相似文献
8.
George Teodoro Eduardo Valle Nathan Mariano Ricardo Torres Wagner Meira Jr Joel H. Saltz 《The VLDB Journal The International Journal on Very Large Data Bases》2014,23(3):427-448
Similarity search in high-dimensional spaces is a pivotal operation for several database applications, including online content-based multimedia services. With the increasing popularity of multimedia applications, these services are facing new challenges regarding (1) the very large and growing volumes of data to be indexed/searched and (2) the necessity of reducing the response times as observed by end-users. In addition, the nature of the interactions between users and online services creates fluctuating query request rates throughout execution, which requires a similarity search engine to adapt to better use the computation platform and minimize response times. In this work, we address these challenges with Hypercurves, a flexible framework for answering approximate k-nearest neighbor (kNN) queries for very large multimedia databases. Hypercurves executes in hybrid CPU–GPU environments and is able to attain massive query-processing rates through the cooperative use of these devices. Hypercurves also changes its CPU–GPU task partitioning dynamically according to the observed load, aiming for optimal response times. In our empirical evaluation, dynamic task partitioning reduced query response times by approximately 50 % compared to the best static task partition. Due to a probabilistic proof of equivalence to the sequential kNN algorithm, the CPU–GPU execution of Hypercurves in distributed (multi-node) environments can be aggressively optimized, attaining superlinear scalability while still guaranteeing, with high probability, results at least as good as those from the sequential algorithm. 相似文献
9.
Mar Arenas-Parra Amelia Bilbao-Terol Mariano Jiménez 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2016,20(6):2341-2352
This paper proposes a pragmatic model for multi-objective decision-making processes involving clusters of objectives which have a decisional meaning for the decision maker (DM). We provide the DMs with a comfortable tool that allows them to express their preferences both by comparing criteria of the same cluster and via the comparison between the different clusters. In standard goal programming the importance of the goals is modeled by the introduction of preferential weights or/and the incorporation of pre-emptive priorities. However, in many cases the DM is not able to establish a precise preference structure. Even in the case of precise weights the solution does not match necessarily the relative weights or, in the case of precise pre-emptive priority, the result could be very restrictive. In order to overcome these drawbacks, in this paper the normalized unwanted deviations are interpreted in terms of achievement degrees of the goals and fuzzy relations are used to model the relative importance of the goals. Thus, we show how several methodologies from the fuzzy goal programming literature can be tailored for solving standard GP problems. We apply this new modeling to problems where there is a “natural” clustering between goals of the same class. We address this situation by solving two phases; in the first one each class is handled separately taking into account the hierarchy of their goals and, in the second phase, we integrate the results of the first phase and the imprecise hierarchy of the different classes. We formulate a new goal programming model called as sequential goal programming with fuzzy hierarchy model. Because many real situations involve decision making in this environment, our proposal can be a useful tool of broad application. A numerical example illustrates the methodology. 相似文献
10.
Mariano J. Savelski C. Stewart Slater Paul V. Tozzi Christian M. Wisniewski 《Clean Technologies and Environmental Policy》2017,19(10):2467-2477
This study explores design alternatives for the purification and possible reuse of low-volume organic solvents waste streams in pharmaceutical manufacturing. Solvent use has a large impact on the life cycle of pharmaceutical processes, as typically 80–90% of the total mass used in the production of an active pharmaceutical ingredient is attributed to solvent use. Solvents are not consumed in pharmaceutical processes so they exit the process as waste. These waste streams are usually disposed of using incineration; therefore, generating significant life cycle emissions from disposal and replacement of virgin solvent. Solvent recovery efforts are generally limited to large-volume waste streams. However, results show that solvents in low-volume streams can also be economically recovered using a versatile multi-campaign solvent recovery skid. Three different solvent waste streams were evaluated, and 85.3% reduction in total emissions and 86.3% reduction in operating costs were achieved. Investment in the solvent recovery system was determined to have a payback period of 4.5 years and a 28% IRR over 10 years. A life cycle impact assessment shows impacts on the human health, ecosystems, and resources categories have been reduced by 82.4, 85.1, and 87.1%, respectively. 相似文献