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11.
The augmentation in electricity demand, power system privatization as well as efficacy of renewable resources has
paved the way for power system companies and researchers to exploit the field of grid connected distributed
generation (DG) and its issues, islanding being a dominant one. Several research works have been conducted to
mitigate the issues of islanding detection (ID). In context of this, the paper gives a comprehensive review of
islanding issues, standard test systems, criteria and shifting of research trends in islanding detection methods
(IDMs). The significant contributions pertain to categorization of IDMs, evaluation of non-detection zone (NDZ) for
each test system, disquisition on evolution and advancement of IDMs and its comparisons based on criteria such as
NDZ, run on time, nuisance tripping percentage, applicability in multi DG system and implementation cost to draw
out the strength and shortcomings of individual methods that will come to aid to the companies or researchers for
establishing the applicability and appropriateness of such method for their concerned domain. 相似文献
12.
Jeffrey Beck Richard Scritchfield Billy Sullivan Jamie Teherani Chang-Feng Wan Mike Kinch Martha Ohlson Mark Skokan Lewis Wood Pradip Mitra Mike Goodwin Jim Robinson 《Journal of Electronic Materials》2009,38(8):1579-1592
The operation of the mid-wave infrared (MWIR) HgCdTe cylindrical electron injection avalanche photodiode (e-APD) is described.
The measured gain and excess noise factor are related to the collection region fill factor. A two-dimensional diffusion model
calculates the time-dependent response and steady-state pixel point spread function for cylindrical diodes, and predicts bandwidths
near 1 GHz for small geometries. A 2 μm diameter spot scan system was developed for point spread function and crosstalk measurements at 80 K. An electron diffusion
length of 13.4 μm was extracted from spot scan data. Bandwidth data are shown that indicate bandwidths in excess of 300 MHz for small unit
cells geometries. Dark current data, at high gain levels, indicate an effective gain normalized dark density count as low
as 1000 counts/μs/cm2 at an APD gain of 444. A junction doping profile was determined from capacitance–voltage data. Spectral response data shows
a gain-independent characteristic. 相似文献
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15.
Channel estimation in a multipath mobile communication system is addressed in this paper, and a novel approach based on the
linear prediction in frequency domain and the singular value decomposition technique is presented for joint estimation of
the angles of arrival and the time delays of multiple reflections of a known signal. Simulation results illustrating the performance
of the proposed algorithm are included, and the results show that the proposed method is close in accuracy when compared to
the iterative maximum-likelihood method. However, when the two methods are compared in computational complexity, it is demonstrated
that the proposed method reduces the complexity to nearly half of that of the maximum-likelihood method. The Cramer–Rao bounds
are computed for comparison. 相似文献
16.
17.
Swetapadma PANDA Nikhil P. ZADE Pradip SARKAR Robin DAVIS 《Frontiers of Structural and Civil Engineering》2022,16(1):117-130
Proven research output on the behavior of structures made of waste copper slag concrete can improve its utilization in the construction industry and thereby help to develop a sustainable built environment. Although numerous studies on waste copper slag concrete can be found in the published literature, no research has focused on the structural application of this type of concrete. In particular, the variability in the strength properties of waste copper slag concrete, which is required for various structural applications, such as limit state design formulation, reliability-based structural analysis, etc., has so far not attracted the attention of researchers. This paper quantifies the uncertainty associated with the compressive-, flexural- and split tensile strength of hardened concrete with different dosages of waste copper slag as fine aggregate. Best-fit probability distribution models are proposed based on statistical analyses of strength data generated from laboratory experiments. In addition, the paper presents a reliability-based seismic risk assessment of a typical waste copper slag incorporated reinforced concrete framed building, considering the proposed distribution model. The results show that waste copper slag can be safely used for seismic resistant structures as it results in an identical probability of failure and dispersion in the drift demand when compared with a conventional concrete building made of natural sand. 相似文献
18.
In this paper, a fast yet accurate CMOS analog circuit sizing method, referred to as Iterative Sequential Geometric Programming (ISGP), has been proposed. In this methodology, a correction factor has been introduced for each parameter of the geometric programming (GP) compatible device and performance model. These correction factors are updated using a SPICE simulation after every iteration of a sequential geometric programming (SGP) optimization. The proposed methodology takes advantage of SGP based optimization, namely, fast convergence and effectively optimum design and at the same time it uses SPICE simulation to fine tune the design point by rectifying inaccuracy that may exists in the GP compatible device and performance models. In addition, the ISGP considers the requirement of common centroid layout and yield aware design centering for robust final design point specifying the number of fingers and finger widths for each transistor which makes the design point ready for layout. 相似文献
19.
Poly(m-aminophenol) (PmAP) was synthesized by the oxidative polymerization of m-aminophenol in sodium hydroxide medium using ammonium persulfate oxidant at room temperature. The synthesized polymer showed very good solution processability as it was well soluble in aqueous sodium hydroxide, dimethylsulfoxide (DMSO), dymethylformamide (DMF), etc. A free-standing film was cast from thermal evaporation of DMSO solution of the synthesized PmAP. The film was then doped with aqueous sodium hydroxide and methanol mixture by solution doping technique at room temperature. The doping conditions were standardized in terms of the DC-conductivity of the doped film. The doped PmAP was characterized by ultraviolet–visible spectroscopy, Fourier transform infrared spectroscopy, Electron dispersion spectroscopy, X-ray diffraction spectroscopy, elemental analysis by atomic absorption spectroscopy, thermogravimetric analysis and DC-electrical conductivity. The DC-electrical conductivity of PmAP film was increased to 2.34 × 10?5 S/cm from <10?12 S/cm due to sodium ion doping. From all the above characterizations it was confirmed that the sodium ions were not the reason for the conduction. The incorporated sodium cation in the polymer through free –OH groups of the polymer chain was induced the electron cloud of the polymer and so the polymer became conducting. 相似文献
20.
Genevieve M. Halpenny Rachel C. Steinhardt Krystle A. Okialda Pradip K. Mascharak 《Journal of materials science. Materials in medicine》2009,20(11):2353-2360
A light-activated NO donor, [Mn(PaPy3)(NO)]ClO4 (1a), has been incorporated into HEMA-based polymer hydrogel and the nitrosyl-polymer conjugate materials 1ax · HG and 1ax · HGMB have been characterized. The NO releasing properties and antibacterial capabilities of these materials in conjunction with
growth attenuators such as hydrogen peroxide and methylene blue (MB) are reported. Since the nitrosyl releases NO only upon
exposure to light, materials like 1ax · HGMB could be used as wound dressings that deliver NO under controlled conditions. 相似文献