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11.
Power distribution systems have been significantly affected by many outage-causing events. Good fault cause identification can help expedite the restoration procedure and improve the system reliability. However, the data imbalance issue in many real-world data sets often degrades the fault cause identification performance. In this paper, the E-algorithm, which is extended from the fuzzy classification algorithm by Ishibuchi to alleviate the effect of imbalanced data constitution, is applied to Duke Energy outage data for distribution fault cause identification. Three major outage causes (tree, animal, and lightning) are used as prototypes. The performance of E-algorithm on real-world imbalanced data is compared with artificial neural network. The results show that the E-algorithm can greatly improve the performance when the data are imbalanced 相似文献
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M Hafezparast CG Cole GP Kaur RS Athwal PA Jeggo 《Canadian Metallurgical Quarterly》1994,20(6):541-548
A hamster-human hybrid containing only the q arm of chromosome 2 has been used to construct a panel of hybrids bearing reduced regions of chromosome 2 using the technique of irradiation fusion gene transfer. The human chromosome 2 carried the Ecogpt gene and all hybrids were selected using this marker. The integrated Ecogpt gene was localized to the region 2q33-34, resulting in the selective retention of this region in the hybrids. These data were combined with another previously constructed panel of hybrids containing regions of 2q, which were enriched for the region 2q36-37. The combined hybrid panel is useful for the mapping of new markers to defined regions of chromosome 2 and for the cloning of genes located on 2q by a positional strategy. 相似文献
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In a prospective study of layered versus mass closure of abdominal incisions in infants and children, 34 cases underwent wound closure by layered and mass closure technique on an alternate basis. All the patients were assessed for their nutritional status and haemoglobin level pre-operatively, and wound complications were compared with respect to closure technique, nutritional status and normal haemoglobin level. Presence of protein energy malnutrition and anaemia did not increase the risk of wound complications with either of the technique. 相似文献
17.
SV Filippov MD Rekhter RS Polishchuk SV Gurkin SN Voronov VI Cherviakov AA Mironov 《Canadian Metallurgical Quarterly》1993,35(9):62-65
It has been shown that changes in the orientation of arterial smooth muscle cells during a constant longitudinal stretching of the artery in vivo are not similar in different sections of the stretching zone. Cells in the proximal and distal sections keep their orientation but this orientation differs from that of smooth muscle cells in the control arteries. Cells in the central part of the stretching region lose their definite orientation to settle randomly. 相似文献
18.
DR Calderone BG Loder D Denny RS Sticha SJ Wertheimer 《Canadian Metallurgical Quarterly》1996,35(3):230-236
A seroprevalence survey to recently proposed adenovirus (AV) serotypes AV 48 and AV 49, isolated primarily from AIDS patients, was conducted among the San Francisco Men's Health Study cohort. This cohort of homosexual, heterosexual, or bisexual HIV-seronegative and -seropositive men from selected San Francisco census tracts has been studied since 1984. The presence or absence of type-specific antibody in 628 serum specimens from 1989 was determined by microneutralization. Thirty of these subjects (26 positive and four negative) were studied longitudinally. Serum specimens taken at 6-month intervals from 1984 to 1993 were tested to characterize antibody response and to document the advent of these new serotypes. Eight subjects were tested against five other AV serotypes for comparison. AV 48 and AV 49 seroprevalence rates were significantly higher in HIV-seropositives, but infection was not limited to the immunocompromised. Sexual preference was not a significant determinant for AV seroprevalence in HIV-seronegatives. However, the extent and duration of the neutralizing antibody response was strikingly different between homosexuals and heterosexuals: an endemic pattern of continuous reexposure over the 9-year period was seen in 90% of 19 homosexuals, while five of six heterosexuals (83%) had an episodic pattern of exposure with antibody decline to undetectable levels. These data suggest that these viruses may be endemic in some part of the homosexual population and that sexual transmission may be the primary source of continuous reexposure. 相似文献
19.
RS McLachlan 《Canadian Metallurgical Quarterly》1997,14(5):358-368
Electrical stimulation of the vagus nerve in the neck by using a programmable stimulator similar to a cardiac pacemaker is being explored as a treatment for epilepsy. There is sound rationale based on studies of animal seizure models for pursuing this treatment modality, and early clinical trials provide support for efficacy in patients with intractable epilepsy at least equivalent to that of some of the new antiepileptic drugs. Safety and tolerability have been demonstrated in >800 patients worldwide since the first implant in 1988. Most of these had partial seizures for which resective epilepsy surgery was not feasible or had failed, but efficacy of vagal stimulation appears to be the same for both partial and generalized epilepsy. Specific selection criteria for this procedure have yet to be established, and further studies are warranted to determine whether vagal stimulation becomes an accepted procedure for epilepsy management. 相似文献
20.
Lewis D.M. Galloway D.R. Van Ierssel M. Rose J. Chow P. 《Very Large Scale Integration (VLSI) Systems, IEEE Transactions on》1998,6(2):188-198
This paper describes the Transmogrifier-2 (TM-2), a second-generation multifield programmable gate array (FPGA) rapid-prototyping system. The largest version of the system will comprise 16 boards that each contain two Altera 10K50 FPGA's, four I-Cube interconnect chips, and up to 8 Mbytes of memory. The inter-FPGA routing architecture of the TM-2 uses a novel interconnect structure, a nonuniform partial crossbar, that provides a constant delay between any two FPGA's in the system. The TM-2 architecture is modular and scalable, meaning that systems of various sizes can be constructed from copies of the same board, while maintaining routability and the constant delay feature. Other features include a system-level programmable clock that allows single-cycle access to off-chip memory, and programmable clock waveforms with edge resolution of 10 ns. The first Transmogrifier-2 boards have been manufactured and are functional. They have recently been used successfully in some simple graphics acceleration applications 相似文献