A novel hierarchical neural networks (HNNs) method for fault diagnosis of large-scale circuits is proposed. The presented techniques using neural networks(NNs) approaches require a large amount of computation for simu...A novel hierarchical neural networks (HNNs) method for fault diagnosis of large-scale circuits is proposed. The presented techniques using neural networks(NNs) approaches require a large amount of computation for simulating various faulty component possibilities. For large scale circuits, the number of possible faults, and hence the simulations, grow rapidly and become tedious and sometimes even impractical. Some NNs are distributed to the torn sub-blocks according to the proposed torn principles of large scale circuits. And the NNs are trained in batches by different patterns in the light of the presented rules of various patterns when the DC, AC and transient responses of the circuit are available. The method is characterized by decreasing the over-lapped feasible domains of responses of circuits with tolerance and leads to better performance and higher correct classification. The methodology is illustrated by means of diagnosis examples.展开更多
A new route was described to synthesize Arg-Gly-Asp-X（RGDX,X=amino acid） tetrapeptide.To better understand the method,the tetrapeptide Arg-Gly-Asp-CySS（RGDCySS） was chosen as a model target for X.First,GDCySS was ...A new route was described to synthesize Arg-Gly-Asp-X（RGDX,X=amino acid） tetrapeptide.To better understand the method,the tetrapeptide Arg-Gly-Asp-CySS（RGDCySS） was chosen as a model target for X.First,GDCySS was obtained in four steps,comprising the chloroacetylation of L-aspartic acid（ClCH2COAsp）,synthesis of chloroacetyl L-aspartic acid anhydride[ClCH2COAsp（CO）2O],formation of ClCH2COAsp-CySS and ammonolysis of ClCH2COAsp-CySS.Second,preparation of Arg-NCA,which was coupled with GDCySS to synthesize RGDCySS by the NCA method（Leuchs＇ anhydrides method,NCA：N-carboxy-a-amino acid anhydride）.The purity of the product was analyzed by the high performance liquid chromatography（HPLC）.Molecular weights of the peptide products were confirmed by mass spectroscopy.In the developed approach,less protected amino acids were used compared to conventional solid-phase synthesis.The new route offers advantages of low cost,simplicity and rapid synthesis with a reasonable yield of 63.0％（calculated according to arginine content）.展开更多
基金the Natural Science Foundation of China (No50677014)Doctoral Special Fund of China Ministry of Education, (No. 20060532002)+2 种基金the Program for New Century ExcellenTalents in University (No. NCET-04-0767)Foundation of Hunan Province Science & Technology (Nos. 06JJ2024, 03GKY3115,04FJ2003,05GK2005)the National High-Tech Research and Development (863) Program of China.
文摘A novel hierarchical neural networks (HNNs) method for fault diagnosis of large-scale circuits is proposed. The presented techniques using neural networks(NNs) approaches require a large amount of computation for simulating various faulty component possibilities. For large scale circuits, the number of possible faults, and hence the simulations, grow rapidly and become tedious and sometimes even impractical. Some NNs are distributed to the torn sub-blocks according to the proposed torn principles of large scale circuits. And the NNs are trained in batches by different patterns in the light of the presented rules of various patterns when the DC, AC and transient responses of the circuit are available. The method is characterized by decreasing the over-lapped feasible domains of responses of circuits with tolerance and leads to better performance and higher correct classification. The methodology is illustrated by means of diagnosis examples.
基金Supported by the National Natural Science Foundation of China（No.81271697）, the Science Foundation of Changchun City, China（No.09SF02）, the China Postdoctoral Science Foundation（No.20100481048）, the Specialized Research Fund for the Doctoral Program of Higher Education of China（No.20100061120077） and the Social Development Project of Science and Tech- nology Department of Jilin Province, China（Nos.20106031, 20120967, YYZX2012）.
文摘A new route was described to synthesize Arg-Gly-Asp-X（RGDX,X=amino acid） tetrapeptide.To better understand the method,the tetrapeptide Arg-Gly-Asp-CySS（RGDCySS） was chosen as a model target for X.First,GDCySS was obtained in four steps,comprising the chloroacetylation of L-aspartic acid（ClCH2COAsp）,synthesis of chloroacetyl L-aspartic acid anhydride[ClCH2COAsp（CO）2O],formation of ClCH2COAsp-CySS and ammonolysis of ClCH2COAsp-CySS.Second,preparation of Arg-NCA,which was coupled with GDCySS to synthesize RGDCySS by the NCA method（Leuchs＇ anhydrides method,NCA：N-carboxy-a-amino acid anhydride）.The purity of the product was analyzed by the high performance liquid chromatography（HPLC）.Molecular weights of the peptide products were confirmed by mass spectroscopy.In the developed approach,less protected amino acids were used compared to conventional solid-phase synthesis.The new route offers advantages of low cost,simplicity and rapid synthesis with a reasonable yield of 63.0％（calculated according to arginine content）.
