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排序方式: 共有489条查询结果,搜索用时 31 毫秒
1.
Maria A. Ospina Monica Pizarro Thierry Tran Julien Ricci John Belalcazar Jorge L. Luna Luis F. Londoño Sandra Salazar Hernan Ceballos Dominique Dufour Luis A. Becerra Lopez-Lavalle 《International Journal of Food Science & Technology》2021,56(3):1343-1353
The objective of this study was to characterise the nutritional potential of leaves and identify a diversity centre with low cyanide and high nutrient content among 178 Latin American cassava genotypes. This field-based collection represents the seven diversity centres, held at The International Center for Tropical Agriculture (CIAT Palmira, Colombia) by the Cassava Program. The cyanide, all-trans-β-carotene and lutein concentrations in cassava leaves ranged from 346 to 7484 ppm dry basis (db), from 174–547 μg g−1 db and 15–181 μg g−1 db, respectively. Cassava leaves also showed significant levels of essential amino acids leucine, lysine, phenylalanine, valine and threonine, and average total protein content of 26.24 g 100 g−1 db. Among seven diversity centres, South American rainforest group showed low cyanide and high carotene content in leaves. In addition, VEN77 and PAN51 genotypes stood out for having low cyanide in leaves and roots and high carotene in leaves. This genetic diversity can be used to select high potential progenitors for breeding purposes. 相似文献
2.
Handheld and other battery-powered ICs require process scaling to increase functional integration and reduce active power consumption. Scaling also increases leakage current components to the point where standby power is frequently a limiting design factor. A scheme combining low-leakage thick-gate shadow latches and high-performance transistors is presented that decouples performance from standby power in sub-130-nm technologies. Circuit design and operation, including pulse-clocked latches, use of dynamic circuits, and inclusion of scan is presented. The approach is validated by experimental results on a 90-nm process. 相似文献
3.
The use of neural networks as global approximation tool in crashworthiness problems is here investigated. Neural networks are not only asked to return some meaningful indices of the structural behavior but also to reproduce load-time curves during crash phenomena. To contain the number of examples required for the training process, parallel subsystems of small neural networks are designed. Design points for the training process are obtained by explicit finite element analyses performed by PAMCRASH. The settlement of the points in the design domain is defined using a maximum distance concept. The procedure is applied to different typical absorption structures made of aluminum alloy: riveted tubes, honeycomb structures, longitudinal keel beam and intersection elements of helicopter subfloors. 相似文献
4.
Andrea Omicini Alessandro Ricci Mirko Viroli 《Electronic Notes in Theoretical Computer Science》2006,150(3):21-36
Human intelligence has evolved along with the use of more and more sophisticated tools, allowing Homo Faber (from Homo Habilis to Homo Sapiens Sapiens) to cope with environment changes, as well as to adapt the environment to his needs. Analogously, in this seminal paper we introduce the notion of Agens Faber, conveying the idea that agent intelligence should not be considered as separated by the agent ability to perceive and affect the environment—and so, that agent intelligence is strictly related to the artefacts that enable, mediate and govern any agent (intelligent) activity.
Along this line, we first discuss the notion of artefact for MAS in general, then we try to devise out the admissible / required / desirable features of an artefact for MAS. We elaborate on the many sorts of possible relations between agents and artefacts, focusing in particular on the issue of the rational exploitation of artefacts, and also rough out a possible taxonomy of artefacts for MAS. 相似文献
5.
Adaptive Radar Detection of Distributed Targets in Homogeneous and Partially Homogeneous Noise Plus Subspace Interference 总被引:5,自引:0,他引:5
Bandiera F. De Maio A. Greco A.S. Ricci G. 《Signal Processing, IEEE Transactions on》2007,55(4):1223-1237
This paper addresses adaptive radar detection of distributed targets in noise plus interference assumed to belong to a known or unknown subspace of the observables. At the design stage we resort to either the GLRT or the so-called two-step GLRT-based design procedure and assume that a set of noise-only data is available (the so-called secondary data). Detection algorithms have been derived modeling noise vectors, corresponding to different range cells, as independent, zero-mean, complex normal ones, sharing either the same covariance matrix (homogeneous environment) or the same covariance matrix up to possibly different (mean) power levels between primary data, i.e., range cells under test, and secondary ones (partially homogeneous environment). The performance assessment has been conducted by Monte Carlo simulation, also in comparison to previously proposed detection algorithms, and confirms the effectiveness of the newly proposed ones 相似文献
6.
This paper discuss several quantitative issues that arise in the analysis of health risks, beginning with principles such as de minimis and zero-risk. The paper also provides a probabilistic definition of risk in terms of hazard, context, consequence, magnitude, and uncertainty. The example relies on this definition to investigate, through sensitivity analysis, the effect that uncertainty has on the results obtained. The results, from a case study based on waterborne total arsenic, show that the choice of dose—response functions causes more uncertainty than any other component of risk analysis. Chemical carcinogenesis provides the basis for discussing inability to know as well as uncertainty. The conclusion is that risk analysis keeps uncertainty and inability to know separate; through this function, it provides a much needed method to present information to decision makers and the public. 相似文献
7.
F Venuta T De Giacomo EA Rendina C Ricci GF Coloni 《Canadian Metallurgical Quarterly》1998,66(5):1833-1834
Lung volume reduction has been performed in patients with advanced emphysema to relieve dyspnea and improve exercise tolerance. Median sternotomy and video-assisted thoracoscopy have been proposed as equally adequate approaches; however, prolonged postoperative air leakage is the most prevalent complication in all series. For this reason, on the basis of the experience achieved with the median sternotomy approach, buttressing of the suture line with different materials and techniques for space reduction have been proposed. We describe a technique to create a pleural tent after thoracoscopic volume reduction. The thoracoscopic creation of a pleural tent is feasible and results in a duration of postoperative air leaks and hospital stays similar to that achieved with stapler line buttressing. 相似文献
8.
Demartini G. Granelli G.P. Marannino P. Montagna M. Ricci M. 《Power Systems, IEEE Transactions on》1996,11(4):1785-1791
The paper deals with the problem of improving co-ordination between the online economic dispatch (ED) function and the very short-term advance dispatch (AD). Both procedures are formulated as optimal dispatching problems, but while a static model is used for the ED function, a dynamic model is employed in AD. The need to account for ramp-rate limits of thermal power generation even in the ED phase is satisfied by adding suitable penalty terms to the objective function of the classical ED problem. These penalties are proportional to the Lagrange multipliers associated with ramp-rate limits that are active at the AD solution. An efficient updating procedure is used to correct the penalization by taking the load forecast errors into account. The proposed co-ordination procedure can provide the snapshot ED with the long range perspective of AD without resorting to heuristic approaches. The procedure is validated by extensive testing carried out both on a small CIGRE test case and on a medium-large scale network representative of the Italian EHV system. Moreover, test results show that the CPU time requirements of the modified ED procedure are still suited to online applications 相似文献
9.
The surface tension of liquid tin has been measured by the sessile-drop technique as a function of temperature, in the range 232 T (°C) 800 and under different atmospheres. It is shown that oxygen strongly affects the surface tension values and that, under nominally very clean conditions, a considerable scatter of experimental results occurs. This scatter can be explained by taking into account kinetic factors, especially those related to the gaseous fluxes around the molten drop. By this procedure, a number of experimental results can be singled out, which corresponds to clean surface conditions. On the basis of these results, the following expression for surface tension politherm is proposed: (mN m–1 = 581-0.13) (t-232). 相似文献
10.
Linas Baltrunas Bernd Ludwig Stefan Peer Francesco Ricci 《Personal and Ubiquitous Computing》2012,16(5):507-526
In order to generate relevant recommendations, a context-aware recommender system (CARS) not only makes use of user preferences, but also exploits information about the specific contextual situation in which the recommended item will be consumed. For instance, when recommending a holiday destination, a CARS could take into account whether the trip will happen in summer or winter. It is unclear, however, which contextual factors are important and to which degree they influence user ratings. A large amount of data and complex context-aware predictive models must be exploited to understand these relationships. In this paper, we take a new approach for assessing and modeling the relationship between contextual factors and item ratings. Rather than using the traditional approach to data collection, where recommendations are rated with respect to real situations as participants go about their lives as normal, we simulate contextual situations to more easily capture data regarding how the context influences user ratings. To this end, we have designed a methodology whereby users are asked to judge whether a contextual factor (e.g., season) influences the rating given a certain contextual condition (e.g., season is summer). Based on the analyses of these data, we built a context-aware mobile recommender system that utilizes the contextual factors shown to be important. In a subsequent user evaluation, this system was preferred to a similar variant that did not exploit contextual information. 相似文献