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In this paper, a model of the 330kV GIS substation shell in transient state is established, a simulation calculation about transient enclosure voltage (TEV) generated during switching of disconnector is carried out, and the TEV waveforms and spectral distributions were obtained throughout the shell. The simulation results are compared with the actual experimental data of the substation, and on the basis of verifying the correctness of the simulation calculation, the possible hazards caused by transient elevation of potential to ground are analyzed. The study shows that the maximum value of TEV always appears on the shell of the bushing, which can reach tens kV voltage level and contain complex frequency. At the same time, the transient potential difference between the grounding wire and the grounding terminal of the control room is up to 1000V.

Concept and application of on-line monitoring technology and corresponding system was booming for recent decades, however, there was no overall top-level design for on-line monitoring even though it has been researched and applied for a long time. In this paper, we offered a novel and necessary top-level design for overall on-line monitoring system, including the structure, the layer and the function, which would possibly bridge scientific research with technology management. A three-layer design with seven sections at top layer was brought up. The design of top layer was conceived of seven separate yet connected sections, including terminology and definition, general specification, structure, measurement link, information interface, evaluation and stabilization. Contents, roles and ranges of different sections were demonstrated while logical relationships, supports and connections between these sections were also carefully illustrated. Admittedly, the top layer was focus of the whole top-level design, functions and utility of the second and the third layer was also specifically introduced.

The paper concerns improvement of the acoustic emission (AE) methods applied in diagnosing of insulations systems of electric power transformer. During detection of AE signals emitted by partial discharges (PD) occurring in insulation systems of power transformer, there exist different forms of interference sources, which may have a direct impact on the correct evaluation of the measured signals obtained using the AE method. Thus, analysis of the impact of interfering signals on the PD detection and classification is performed. In this study, a correlation-based wavelet base selection method is introduced. The proposed wavelet analysis approach capable of conserving a significant portion of the original signal, while the threshold value determined based on the relative difference between the original and noisy signal. The proposed method is applied to PD signals that obtained in the field. With the comparison of other de-noising methods, the de-noised PD signals indicate that the proposed method yields higher reduction in noise levels.

This research describes the p-type nanostalactites (p-type NS) with high photothermal conversion capability has been demonstrated by rapid INC process without extra heat treatment. In optical property, p-type NS has ultralow reflectance below 5 % and high light absorption due to rough structures in the broadband wavelength (350 nm–1100 nm). It looks like a black body. Silicon, an indirect band material, can release thermal energy during the recombination process of photo-generated electron-hole pairs. P-type NS converts photon energy into heat rapidly and then photothermal effect occurs. Then, the temperature change of p-type NS is faster in 10 second than bulk p-type silicon. These nanostructures can not only enhance thermal conversion efficiency but be regarded as a great heat absorber.

In this study, we demonstrate the high performance few-layer graphene-Si sensor with high photoresponsivity of 95 mA/W, operation behaviors with external bias as low as 0 V, and broadband operating light wavelength from 400 nm to 1000 nm by combining high transparency of few-layer graphene and n-type silicon. Although external bias benefits the photoresponsivity, the larger dark current is the price to pay. Under zero bias, the different Si substrate, n-type or p-type, provides variant Schottky barrier height guiding different photoelectrical behavior also be investigated in this work. According to the experimental results, few-layer graphene over p-type silicon (FLG p-Si) has one order higher the dark current of the few-layer graphene over n-type silicon (FLG n-Si) to ensure that the detection region between few-layer graphene and n-type silicon profits high optical-to-electrical conversion. Further, the capability of photocurrent-to-photovoltage conversion directly in one device is also provided and verified to profit the integration proposed device with periphery circuit easily.

Gamma amino butyric acid (GABA) is the major inhibitory neurotransmitter in the human brain. Alterations in GABA Level are associated with a variety of neurological and psychiatric disorders. However, noninvasive in vivo measurement of GABA is hindered by its low concentration and the presence of overlapping resonances. This paper proposed a novel method with wavelet transform to process typical MR spectrum. With this method, signal of GABA was successfully extracted from patients with depressive disorder and controls. Changes of GABA were also observed in patient group suggesting the feasibility of wavelet transform in processing of MR spectrum.

In this paper, it is demonstrated that the DNA-based algorithm [Ho et al. 2005] for solving an instance of the clique problem to any a graph G = (V, E) with n vertices and q edges and its complementary graph = (V, ) with n vertices and m = (((n * (n – 1)) / 2) – q) edges can be implemented by Hadamard gates, NOT gates, CNOT gates, CCNOT gates, Grover’s operators, and quantum measurements on a quantum computer.

In this paper, it is demonstrated that quantum implementation of bio-molecular solutions to compute the number of elements in each hitting-set in an instance of the hitting-set problem could be considered as the oracle work in Grover’s algorithm, i.e., the target state labeling, preceding Grover’s searching steps. Finally, for testing our theory, a three-qub it nuclear magnetic resonance (NMR) experiment of solving the simplest hitting-set problem is performed.

Chloroethylnitrosoureas (CENUs) were an important family of anticancer agents in the clinical treatment of human malignancies. Several lines of evidences indicated that their cytotoxicity was related to the interstrand crosslink of DNA. In this study, a method for the determination of DNA crosslink was established using real-time fluorescence quantitative PCR. The DNA crosslink ratio induced by two CENUs, Semustine (Me-CCNU) and Carmustine (BCNU) were quantitatively analyzed and compared. The results showed that BCNU and Me-CCNU exhibit different crosslink trend of double strand DNA. Evagreen, a fluorescent dye, was used as the probe in the assay. This study provided direct evidence that real-time fluorescence quantitative PCR (qPCR) was a more convenient, efficient and stable method to detect DNA crosslink.

In this paper, it is demonstrated that solving an instance of the vertex cover problem of any graph G with m edges and n vertices can be implemented by Hadamard gates, NOT gates, CNOT gates, CCNOT gates, Grover’s operators, and quantum measurements on a quantum computer. To test our theory, an NMR (nuclear magnetic resonance) experiment for the simplest vertex-cover problem is also performed.

In this paper, quantum algorithms for solving an instance of the subset-sum problem is proposed and a NMR experiment for the simplest subset-sum problem to test our theory is also performed.

We demonstrate that the logic computation performed by the DNA-based algorithm for solving general cases of the satisfiability problem can be implemented by our proposed quantum algorithm on the quantum machine proposed by Deutsch. Moreover, we also prove that the logic computation by the bio-molecular operations proposed by Adleman can be implemented by quantum gates (for example, the Hadamard gate, NOT, CNOT, and CCNOT) on the quantum machine. Furthermore, those NP-complete problems solved on a bio-molecular computer are also solvable on a quantum computer. To test our theory, we carry out a three-qubit NMR experiment for solving the simplest satisfiability problem.