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91.
In this paper, we propose a genetic programming (GP) based approach to evolve fuzzy rule based classifiers. For a c-class problem, a classifier consists of c trees. Each tree, T
i
, of the multi-tree classifier represents a set of rules for class i. During the evolutionary process, the inaccurate/inactive rules of the initial set of rules are removed by a cleaning scheme.
This allows good rules to sustain and that eventually determines the number of rules. In the beginning, our GP scheme uses
a randomly selected subset of features and then evolves the features to be used in each rule. The initial rules are constructed
using prototypes, which are generated randomly as well as by the fuzzy k-means (FKM) algorithm. Besides, experiments are conducted in three different ways: Using only randomly generated rules, using
a mixture of randomly generated rules and FKM prototype based rules, and with exclusively FKM prototype based rules. The performance
of the classifiers is comparable irrespective of the type of initial rules. This emphasizes the novelty of the proposed evolutionary
scheme. In this context, we propose a new mutation operation to alter the rule parameters. The GP scheme optimizes the structure
of rules as well as the parameters involved. The method is validated on six benchmark data sets and the performance of the
proposed scheme is found to be satisfactory. 相似文献
92.
Graphene‐based composites offer enhanced catalytic performance of metal and semiconductor nanoparticles, but their development is challenging because catalytic performance strongly depends on the structure and composition of the composite. Herein we show that the catalytic performance of a nanoparticle–graphene composite is very dependent on catalyst loading, which can be optimized for simultaneous enhancement of activity and selectivity. A glassy carbon working electrode has been modified with a gold nanoparticle–graphene (Au–G) composite with a varied number of gold nanoparticles per graphene, so that the conducting property of graphene and the electrocatalytic property of the metal were effectively coupled to give the best catalytic activity and selectivity. The modified electrode was used for simultaneous electrochemical detection of a mixture of electroactive species with high sensitivity. This result shows that the catalytic performance of a graphene‐based composite is sensitive to the catalyst loading and should be optimized for the best performance. 相似文献
93.
Modulation of intramolecular charge transfer reaction of ethyl ester of N,N-Dimethylaminonaphthyl-(acrylic)-acid (EDMANA)
in anionic sodium dodecyl sulfate (SDS), cationic cetyltrimethylammonium bromide (CTAB) and non-ionic p-tert-octylphenoxy polyoxyethanol (Triton-X 100, TX-100) micelles has been addressed using steady state and time resolved spectroscopy.
The interaction of the CT probe EDMANA with micelles and its location inside the micelles have been investigated by the study
of fluorescence spectral band position of EDMANA in micelle, the effective polarity of micelle-water interface and cetyl pyridinium
chloride induced fluorescence quenching measurement. The effects of urea on the properties of the micelles such as Critical
Micelle Concentration and the interaction between EDMANA and micelles have been explored using EDMANA as emission probe. 相似文献
94.
In-plane compression experiments are performed on 3D fine weave pierced C/C composite at a wide strain rate range of 0.0001/s-1000/s.The in-plane compressive fa... 相似文献
95.
The effect of CuSCN as a catalyst in atom‐transfer radical polymerization (ATRP) was investigated. CuSCN can successfully be used for the ATRP of MMA. Substituted bipyridines as well as imines can be used to stabilize the copper complex in solution. CuSCN induces faster polymerization compared to CuBr and CuCl when tosylchloride is used as the initiator. However, the polydispersity is larger than that obtained in the cases of CuCl and CuBr. 相似文献
96.
In this paper, we examine a class of nonlinear, stochastic knapsack problems which occur in manufacturing, facility or other network design applications.Series, merge-and-split topologies of series-parallelM/M/1/K andM/M/C/K queueing networks with an overall buffer constraint bound are examined. Bounds on the objective function are proposed and a sensitivity analysis is utilized to quantify the effects of buffer variations on network performance measures. 相似文献
97.
Biswanath Das Joydeep Banerjee Nikhil Chowdhury Anjoy Majhi Gurram Mahender 《Helvetica chimica acta》2006,89(5):876-883
A simple and convenient synthesis of five important insect pheromones by means of Baylis–Hillman adducts is described, i.e., of (2E,4S)‐2,4‐dimethylhex‐2‐enoic acid ( 1 ), a mandibular‐gland secretion of the male carpenter ant in the genus Camponotus, of (+)‐(S)‐manicone ( 2 ) and (+)‐(S)‐normanicone ( 3 ), two mandibular‐gland constituents of Manica ants, and of (+)‐dominicalure‐I ( 6 ) and (+)‐dominicalure‐II ( 7 ), two aggregation pheromones of the lesser grain borer Rhyzopertha dominica (F). For the first time, the potential of the Baylis–Hillman chemistry for the stereoselective synthesis of trisubstituted olefins was successfully applied to the synthesis of these pheromone compounds. 相似文献
98.
Biswanath Das Nikhil Chowdhury Joydeep Banerjee Anjoy Majhi 《Tetrahedron letters》2006,47(37):6615-6618
An efficient one-pot stereoselective synthesis of trisubstituted (E)-2-methylalk-2-enoic acids has been accomplished by treatment of unactivated Baylis-Hillman adducts, 3-hydroxy-2-methylenealkanoates, with Al-NiCl2·6H2O in methanol at room temperature followed by hydrolysis. The method has been applied to the synthesis of three important insect pheromones, (4S,2E)-2,4-dimethyl-2-hexenoic acid, (+)-(S)-manicone and (+)-(S)-normanicone. 相似文献
99.
Biswanath Das Nikhil Chowdhury K. Damodar K. Ravinder Reddy 《Helvetica chimica acta》2007,90(2):340-345
A simple, mild, rapid, and highly efficient method for the conjugate addition of 1H‐indoles to electron‐deficient olefins has been developed using NaHSO4 ? SiO2 as heterogeneous catalyst. The conversion proceeds at room temperature, and the corresponding Michael adducts are formed in good‐to‐excellent yields. 相似文献
100.
Nikhil Bajpayee Thangavel Vijayakanth Sigal Rencus-Lazar Sneha Dasgupta Aamod V. Desai Rahul Jain Ehud Gazit Rajkumar Misra 《Angewandte Chemie (International ed. in English)》2023,62(6):e202214583
Flexible and biocompatible metal peptide frameworks ( MPFs) derived from short and ultra-short peptides have been explored for the storage of greenhouse gases, molecular recognition, and chiral transformations. In addition to short flexible peptides, peptides with specifically folded conformations have recently been utilized to fabricate a variety of metal helix frameworks ( MHFs ). The secondary structures of the peptides govern the structure-assembly relationship and thereby control the formation of three-dimensional (3D)- MHFs . Particularly, the hierarchical structural organization of peptide-based MHFs has not yet been discussed in detail. Here, we describe the recent progress of metal-driven folded peptide assembly to construct 3D porous structures for use in future energy storage, chiral recognition, and biomedical applications, which could be envisioned as an alternative to the conventional metal-organic frameworks (MOFs). 相似文献