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21.
Diego Carvalho Soares Flávia Maria Santoro Fernanda Araujo Baião 《Journal of Network and Computer Applications》2013,36(6):1451-1465
Knowledge Management aims to promote the growth, communication and preservation of knowledge within an organization, which includes managing the appropriate resources to facilitate knowledge sharing and reuse. Business Process-Oriented Knowledge Management focuses on discovering and representing the dynamic conversion of existing knowledge among participants involved in executing business processes. In this context, Knowledge-Intensive Processes are a very important and challenging specific subclass of processes, since they strongly involve socialization and informal exchanges of knowledge among participants. This paper describes in detail a method for semi-automatic discovery of relevant information characterizing Knowledge-Intensive Processes, as well as the results of further evaluation of the method. Our approach draws on the informal exchange of existing knowledge in collaborative tools such as e-mails. The output is a conceptual map that describes the main elements of a Knowledge-Intensive Process, as well as their relationships. The results from the case study conducted to evaluate the method in an organization underlined the prospects for using collaborative environments to discover the way agents perform their activities. 相似文献
22.
Nair do Amaral Sampaio Neta José Cleiton Sousa dos Santos Soraya de Oliveira Sancho Sueli Rodrigues Luciana Rocha Barros Gonçalves Ligia R. Rodrigues José A. Teixeira 《Food Hydrocolloids》2012
Sugar esters are compounds with surfactant properties (biosurfactants), i.e., capable of reducing the surface tension and promote the emulsification of immiscible liquids. On the other hand, as with all emulsions, coconut milk is not physically stable and is prone to phase separation. Therefore, the aim of this work was to evaluate the synthesis of fructose, sucrose and lactose esters from the corresponding sugars using Candida antarctica type B lipase immobilized in two different supports, namely acrylic resin and chitosan, and evaluate its application in the stabilization of coconut milk emulsions. The enzyme immobilized on chitosan showed the highest yield of lactose ester production (84.1%). Additionally, the production of fructose ester was found to be higher for the enzyme immobilized on the acrylic resin support (74.3%) as compared with the one immobilized on chitosan (70.1%). The same trend was observed for the sucrose ester, although with lower percentage yields. Sugar esters were then added to samples of fresh coconut milk and characterized according to their surface tension, emulsification index and particle size distribution. Although the microscopic analysis showed similar results for all sugar esters, results indicated lactose ester as the best biosurfactant, with a surface tension of 38.0 N/m and an emulsification index of 54.1%, when used in a ratio of 1:10 (biosurfactant:coconut milk, v/v) for 48 h experiments. 相似文献
23.
Daniela López‐Araujo Antonio Loría Arturo Zavala‐Río 《International Journal of Adaptive Control and Signal Processing》2017,31(3):299-313
We solve the simultaneous closed‐loop identification and tracking‐control problems for fully‐actuated Euler–Lagrange systems under input constraints. We use a nonlinear adaptive controller reminiscent of computed‐torque‐type controllers in which linear correction terms are saturated in order to comply with the imposed bounds on the control inputs. Adaptation, reminiscent of gradient methods, is used also with saturation. With respect to related literature, our contribution consists in establishing uniform global asymptotic stability. Therefore, our control scheme ensures robustness with respect to bounded perturbations and uniform convergence of the estimation errors for any initial conditions. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
24.
Raimundo J.B. de Sampaio Jin Yun Yuan 《International journal of systems science》2013,44(10):1087-1094
There are many situations in engineering where we need to calculate the eigensystem of a matrix A which is given as a product of matrices, that is, A = A 1 A 2···A p . Since, usually, we first perform the multiplication of the factors, the matrix A often becomes very ill-conditioned. Actually this happens even when A is a symmetric matrix, which will be our concern here. In this article we introduce a new approach to calculate the eigensystem of A without performing the indicated multiplication, or performing only partially the multiplication of the factors. 相似文献
25.
Ana Dolores Santiago de Freitas Everardo Valadares Sá Barretto de Sampaio Bárbara Laine Ribeiro da Silva Jarcilene Silva de Almeida Cortez R?mulo Sim?es Cezar Menezes 《Nutrient Cycling in Agroecosystems》2012,94(2-3):181-192
Although biological nitrogen fixation (BNF) is considered the main input of N in mature and regenerating native tropical vegetation, it has seldom been quantified. Biomass and N accumulation and fixation were determined for spontaneously occurring herbaceous species in caatinga areas in four regeneration stages (2, 17, 39 and >50?years after abandonment from agricultural use). BNF was estimated using the 15N natural-abundance method. The 2-year regeneration area had the highest total herb (6,355?kg?ha?1) and legume (262?kg?ha?1) biomass production, N stocks (82?kg?ha?1) and fixed N (5.0?kg?ha?1). N2-fixing legumes (nine species in the sampled area) contributed over 97?% of legume biomass in all areas. Macroptilium gracile added the largest amount of N (3.9?kg?ha?1 in the 2-year regeneration area) because of its large biomass production (205?kg?ha?1), although it was not the species with the highest proportion of fixed N (76?%). All of the N2-fixing species obtained large proportions of their N from symbiosis, most of them more than 50?%.However, the amounts of fixed N per unit area were relatively low (0.22?C5.00?kg?ha?1) because the biomass of N2-fixing species was always less than 5?% of the total herb biomass. 相似文献
26.
de Aquino Silva Rogerio da Silva Luana Dutra Moisés Lima de Araujo Gustavo Medeiros 《Mobile Networks and Applications》2021,26(1):319-325
Mobile Networks and Applications - The text mining process typically involves the application of natural language processing (NLP) techniques, in order to obtain important information and extract... 相似文献
27.
Dr. Aline D. de Araujo Huy T. Nguyen Prof. David P. Fairlie 《Chembiochem : a European journal of chemical biology》2021,22(10):1784-1789
The conventional S-alkylation of cysteine relies upon using activated electrophiles. Here we demonstrate high-yielding and selective S-alkylation and S-lipidation of cysteines in unprotected synthetic peptides and proteins by using weak electrophiles and a Zn2+ promoter. Linear or branched iodoalkanes can S-alkylate cysteine in an unprotected 38-residue Myc peptide fragment and in a 91-residue miniprotein Omomyc, thus highlighting selective late-stage synthetic modifications. Metal-assisted cysteine alkylation is also effective for incorporating dehydroalanine into unprotected peptides and for peptide cyclisation via aliphatic thioether crosslinks, including customising macrocycles to stabilise helical peptides for enhanced uptake and delivery to proteins inside cells. Chemoselective and efficient late-stage Zn2+-promoted cysteine alkylation in unprotected peptides and proteins promises many useful applications. 相似文献
28.
ABSTRACT: BACKGROUND: Food and nutritional care quality must be assessed and scored, so as to improve health institution efficacy. This study aimed to detect and compare actions related to food and nutritional care quality in public and private hospitals. METHODS: Investigation of the Hospital Food and Nutrition Service (HFNS) of 37 hospitals by means of structured interviews assessing two quality control corpora, namely nutritional care quality (NCQ) and hospital food service quality (FSQ). HFNS was also evaluated with respect to human resources per hospital bed and per produced meal. RESULTS: Comparison between public and private institutions revealed that there was a statistically significant difference between the number of hospital beds per HFNS staff member (p = 0.02) and per dietitian (p < 0.01). The mean compliance with NCQ criteria in public and private institutions was 51.8% and 41.6%, respectively. The percentage of public and private health institutions in conformity with FSQ criteria was 42.4% and 49.1%, respectively. Most of the actions comprising each corpus, NCQ and FSQ, varied considerably between the two types of institution. NCQ was positively influenced by hospital type (general) and presence of a clinical dietitian. FSQ was affected by institution size: large and medium-sized hospitals were significantly better than small ones. CONCLUSIONS: Food and nutritional care in hospital is still incipient, and actions concerning both nutritional care and food service take place on an irregular basis. It is clear that the design of food and nutritional care in hospital indicators is mandatory, and that guidelines for the development of actions as well as qualification and assessment of nutritional care are urgent. 相似文献
29.
Andrew Procter Andrea Bassi Jenna Kolling Llael Cox Nicholas Flanders Nadav Tanners Rochelle Araujo 《Clean Technologies and Environmental Policy》2017,19(5):1459-1474
Cities worldwide face the challenges of accommodating a growing population, while reducing emissions to meet climate mitigation targets. Public transit investments are often proposed as a way to curb emissions while maintaining healthy urban economies. However, cities face a system-level challenge in that transportation systems have cascading effects on land use and economic development. Understanding how an improved public transit system could affect urban growth and emissions requires a system-level view of a city, to anticipate side effects that could run counter to policy goals. To address this knowledge gap, we conducted a case study on the rapidly growing Research Triangle, North Carolina (USA) region, which has proposed to build a Light Railway by 2026 along a heavily used transportation corridor between the cities of Durham and Chapel Hill. At the same time, Durham County has set a goal of lowering greenhouse gas emissions by 30% from a 2005 baseline by 2030. In collaboration with local stakeholders, we developed a system dynamics model to simulate how Light Rail transit and concurrent policies could help or hinder these sustainable growth goals. The Durham–Orange Light Rail Project (D–O LRP) model simulates urban–regional dynamics between 2000 and 2040, including feedbacks from energy spending on economic growth and from land scarcity on development. Counter to expectations, model scenarios that included Light Rail had as much as 5% higher regional energy use and CO2 emissions than business-as-usual (BAU) by 2040 despite many residents choosing to use public transit instead of private vehicles. This was largely due to an assumption that Light Rail increases demand for commercial development in the station areas, creating new jobs and attracting new residents. If regional solar capacity grew to 640 MW, this would offset the emissions growth, mostly from new buildings, that is indirectly due to Light Rail. National trends in building and automobile energy efficiency, as well as federal emissions regulation under the Clean Power Plan, would also allow significant progress toward the 2030 Durham emissions reduction goal. By simulating the magnitude of technology and policy effects, the D–O LRP model can enable policy makers to make strategic choices about regional growth. 相似文献
30.
L. S. Araujo D. S. dos Santos S. Godet J. Dille A. L. Pinto L. H. de Almeida 《Journal of Materials Engineering and Performance》2014,23(11):4130-4135
In the current work, sheets of superalloy 718 were processed via thermomechanical route by hot and cold rolling, followed by annealing below the δ phase solvus temperature and precipitation hardening to optimum strength. Grain boundary character distribution throughout the processing was mapped via EBSD and its evolution discussed. The results show that it is possible to process the alloy to a fine grain size obtaining concomitantly a considerably high proportion of special boundaries Σ3, Σ9, and Σ27. The precipitation of δ phase presented a strong grain refining role, without significantly impairing the twinning mechanism and, consequently, the Σ3, Σ9, and Σ27 boundary formations. 相似文献