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排序方式: 共有1473条查询结果,搜索用时 31 毫秒
1.
Godfrey C. Onwubolu Petr Buryan Frank Lemke 《The International Journal of Advanced Manufacturing Technology》2008,39(11-12):1080-1092
This paper presents an enhanced approach to predictive modeling for determining tool-wear in end-milling operations based on enhanced-group method of data handling (e-GMDH). Using milling input parameters (speed, feed, and depth-of-cut) and response (tool wear), the data for the model is partitioned into training and testing datasets, and the training dataset is used to realize a predictive model that is a function of the input parameters and the coefficients determined. In our approach, we first present a methodology for modeling, and then develop predictive model(s) of the problem being solved in the form of second-order equations based on the input data and coefficients realized. This approach leads to some generalization because it becomes possible to predict not only the test data obtained during experimentation, but other test data outside the experimental results can also be used. Moreover, this approach makes it easy to present the realized solution in a form that can be further optimized for the input parameters using some optimization techniques. The results realized using our e-GMDH method are promising, and the comparative study presented shows that the e-GMDH outperforms polynomial neural network (PNN); moreover, it is more flexible than the conventional GMDH, which tends to produce nonlinear solutions even for simple problems. In the investigation, the extended particle swarm optimization (PSO) technique was applied to obtain the optimal parameters. Consequently, the modeling approach is extremely useful in realizing a computer-aided process-planning system in an advanced manufacturing environment. 相似文献
2.
A new analytical method has been developed for the determination of the reactive lysine content of soya bean protein. The method is based on the reaction of the free basic groups of the protein with 1-phenylazo-2 naphthol-6,8 disulphonic acid. With regard to the stoichiometry of the procedure, it has been proved, contrary to earlier reports, that the basic amino acids, histidine, arginine and lysine, each combine with one mole of the dye. After acylation with propionic anhydride lysine alone loses its dye reactivity. The usefulness of the proposed method has been demonstrated by the determination of the reactive lysine content of several untreated, heat-treated and acid-treated soya bean samples. The results show that heat damage of about 5% in reactive lysine content can be measured in 1·5 h with good reproducibility. 相似文献
3.
Petr Hájek Radko Mesiar 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2008,12(12):1239-1243
We investigate (quasi)copulas as possible truth functions of fuzzy conjunction which is not necessarily associative and present
some axiom systems for such fuzzy logics. In particular, we study an expansion of Łukasiewicz (infinite valued propositional)
logic by a new connective interpreted as an arbitrary quasicopula (and also by a new connective interpreted as the residuum
of the copula). Main results concern standard completeness. 相似文献
4.
The present paper deals with the problem of solving the (\(n^2 - 1\))-puzzle and cooperative path-finding (CPF) problems sub-optimally by rule-based algorithms. To solve the puzzle, we need to rearrange \(n^2 - 1\) pebbles in the \(n \times n\)-sized square grid using one vacant position to achieve the goal configuration. An improvement to the existing polynomial-time algorithm is proposed and experimentally analyzed. The improved algorithm represents an attempt to move pebbles in a more efficient way compared to the original algorithm by grouping them into so-called snakes and moving them together as part of a snake formation. An experimental evaluation has shown that the snakeenhanced algorithm produces solutions which are 8–9 % shorter than the solutions generated by the original algorithm. Snake-like movement has also been integrated into the rule-based algorithms used in solving CPF problems sub-optimally, which is a closely related task. The task in CPF consists in moving a group of abstract robots on an undirected graph to specific vertices. The robots can move to unoccupied neighboring vertices; no more than one robot can be placed in each vertex. The (\(n^2 - 1\))-puzzle is a special case of CPF where the underlying graph is a 4-connected grid and only one vertex is vacant. Two major rule-based algorithms for solving CPF problems were included in our study—BIBOX and PUSH-and-SWAP (PUSH-and-ROTATE). The use of snakes in the BIBOX algorithm led to consistent efficiency gains of around 30 % for the (\(n^2 - 1\))-puzzle and up to 50 % in for CPF problems on biconnected graphs with various ear decompositions and multiple vacant vertices. For the PUSH-and-SWAP algorithm, the efficiency gain achieved from the use of snakes was around 5–8 %. However, the efficiency gain was unstable and hardly predictable for PUSH-and-SWAP. 相似文献
5.
We compare the fixed parameter complexity of various variants of coloring problems (including List Coloring, Precoloring Extension, Equitable Coloring, L(p,1)-Labeling and Channel Assignment) when parameterized by treewidth and by vertex cover number. In most (but not all) cases we conclude that parametrization by the vertex cover number provides a significant drop in the complexity of the problems. 相似文献
6.
Daniel A.Alexer Anthony Nomezine Lesley A.Jarvis David J.Gladstone Brian W.Pogue Petr Bruza 《光:科学与应用(英文版)》2021,(12):2380-2386
Color vision is used throughout medicine to interpret the health and status of tissue. Ionizing radiation used in radiation therapy produces broadband white lig... 相似文献
7.
Amanda Seemungal Andrea Petróczi Declan P. Naughton 《European Food Research and Technology》2011,233(5):781-789
Several studies have assessed total anti-oxidant activity of wine or individual components in isolation using chemical-based assays. In this study, a quantitative approach was developed to assess the relative anti-oxidant efficacies of selected red wine phenolics via peak reduction, using reversed-phase HPLC. Both intact red wine and phenolic standard solutions were challenged with five oxidant model systems as follows: (1) hydrogen peroxide (H2O2); redox-active metal ions (2) Fe3+ and (3) Cu2+; and the Fenton reagents (4) H2O2 + Fe2+; and (5) H2O2 + Cu+. Treatment with oxidants (1–3) resulted in loss of 47–60% of phenolic standards, which increased to 66–89% for treatment with the Fenton systems, with quercetin exhibiting the optimal anti-oxidant activity. For intact red wine, treatment with oxidants (1–3) led to all phenolic compounds being oxidised (27–77% loss), with caffeic acid and quercetin as the most effective anti-oxidants. For both Fenton systems (4–5), activities in red wine were considerably enhanced for caffeic acid and quercetin, which exhibited the highest anti-oxidant efficacies with 100% peak reduction, while p-coumaric acid and gallic acid were less effective anti-oxidants with peak reductions of 60–68%. The ranking, facilitated by this new quantitative approach, allows comparison of the individual efficacies of the anti-oxidants in a complex matrix. 相似文献
8.
Volker John Petr Knobloch Simona B. Savescu 《Computer Methods in Applied Mechanics and Engineering》2011,200(41-44):2916-2929
Stabilized finite element methods for convection-dominated problems require the choice of appropriate stabilization parameters. From numerical analysis, often only their asymptotic values are known. This paper presents a general framework for optimizing stabilization parameters with respect to the minimization of a target functional. Exemplarily, this framework is applied to the SUPG finite element method and the minimization of a residual-based error estimator, an error indicator, and a functional including the crosswind derivative of the computed solution. Benefits of the basic approach are demonstrated by means of numerical results. 相似文献
9.
Interference due to transmissions by adjacent nodes in a multi-hop wireless network can be modeled using a unit disc graph (UDG). We investigate the reliability associated with using the clique number instead of the chromatic number of the UDG while computing the interference. In our extensive simulations with UDGs of random networks, we observed that the clique number and the chromatic number values were typically very close to one another and the maximum deviation was much less than the theoretical bounds. This implies very high reliability in the proposed approximation. 相似文献
10.
Siu Hong Dexter Wong G. Roshan Deen Jeffrey S. Bates Chiranjit Maiti Ching Ying Katherine Lam Abhishek Pachauri Renad AlAnsari Petr Bělský Jinhwan Yoon Jagan Mohan Dodda 《Advanced functional materials》2023,33(14):2213560
With the advancement of medical and digital technologies, smart skin adhesive patches have emerged as a key player for complex medical purposes. In particular, skin adhesive patches with integrated electronics have created an excellent platform for monitoring health conditions and intelligent medication. However, the efficient design of the adhesive patches is still challenging as it requires a strong combination of network structure, adhesion, physical properties, and biocompatibility. To design an assimilated device, one must have a deep knowledge of various skin adhesive patches. This article provides a comprehensive review of the recent advances in skin-adhesive patches, including hydrogel-based adhesive patches, transdermal patches, and electronic skin (E-skin) patches, for various biomedical applications such as wound healing, drug delivery, biosensing, and health monitoring. Furthermore, the key challenges, implementable strategies, and future designs that can potentially provide researchers in designing innovative multipurpose smart skin patches are discussed. These advanced approaches are promising for managing the health and fitness of patients who require regular medical care. 相似文献