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31.
The characterization of sinusoidal signals with time varying amplitude and phase is useful and applicable for many
fields. Therefore several algorithms have been suggested to estimate main aspects of these signals. Within no
standard approach to test the properties of these algorithms, it seems to be helpful to discuss a large class of
algorithms according to their properties. In this paper, six methods of estimating dynamic phasor have been reviewed
and discussed which three of them are based on least square and others are based on Kalman filter. Taylor expansion
is used as a first step and continued with least square or Kalman filter in accordance with the proposal observer of
each method. The theoretical processes of these methods are briefly clarified. The characterizations have been made
by some tests in time and frequency domains. The tests include amplitude step, phase step, frequency step,
frequency response, total vector error, transient monitor, noise, sample number, computation time, harmonic and DC
offset which build a framework to compare the different methods. 相似文献
32.
Neural Computing and Applications - The automatic narration of a natural scene is an important trait in artificial intelligence that unites computer vision and natural language processing. Caption... 相似文献
33.
34.
Adherence rates to ferric citrate as compared to active control in patients with end stage kidney disease on dialysis 下载免费PDF全文
Diana Jalal Molly McFadden Jamie P. Dwyer Kausik Umanath Erwin Aguilar Yoram Yagil Barbara Greco Mohammed Sika Julia B. Lewis Tom Greene Simin Goral 《Hemodialysis international. International Symposium on Home Hemodialysis》2017,21(2):243-249
Introduction: Oral phosphate binders are the main stay of treatment of hyperphosphatemia. Adherence rates to ferric citrate, a recently approved phosphate binder, are unknown. Methods: We conducted a post‐hoc analysis to evaluate whether adherence rates were different for ferric citrate vs. active control in 412 subjects with end stage kidney disease (ESKD) who were randomized to ferric citrate vs. active control (sevelamer carbonate and/or calcium acetate). Adherence was defined as percent of actual number of pills taken to total number of pills prescribed. Findings: There were no significant differences in baseline characteristics including gender, race/ethnicity, and age between the ferric citrate and active control groups. Baseline phosphorus, calcium, and parathyroid hormone levels were similar. Mean (SD) adherence was 81.4% (17.4) and 81.7% (15.9) in the ferric citrate and active control groups, respectively (P = 0.88). Adherence remained similar between both groups after adjusting for gender, race/ethnicity, age, cardiovascular disease (CVD), and diabetic nephropathy (mean [95% CI]: 81.4% [78.2, 84.6] and 81.5% [77.7, 85.2] for ferric citrate and active control, respectively). Gender, race/ethnicity, age, and diagnosis of diabetic nephropathy did not influence adherence to the prescribed phosphate binder. Subjects with CVD had lower adherence rates to phosphate binder; this was significant only in the active control group. Discussion: Adherence rates to the phosphate binder, ferric citrate, were similar to adherence rates to active control. Similar adherence rates to ferric citrate are notable since tolerance to active control was an entry criteria and the study was open label. Gender, race/ethnicity, nor age influenced adherence. 相似文献
35.
Rasheed S Haider R Hassan N Pachón H Islam S Jalal CS Sanghvi TG 《Food and nutrition bulletin》2011,32(3):192-200
36.
Jalal Salami Akio Shibata Daniel Meier Edgar Kochka Satoshi Yamanaka Preston Davis John Easoz Toru Abe Kazuo Kinoshita 《Solar Energy Materials & Solar Cells》1997,48(1-4)
This paper presents, for the first time, a low-cost, high-throughput manufacturing approach for fabricating n-base dendritic web silicon solar cells with selectively doped emitters and self-aligned aluminum contacts using rapid thermal processing (RTP) and screen printing. The self-aligned locally diffused emitter (SALDE) structure is p+ nn++ where aluminum is screen-printed on a boron-doped emitter and fired in a belt furnace to form a deep self-doped p+-layer and a self-aligned positive contact to the emitter according to the well-known aluminum-silicon (Al---Si) alloying process. The SALDE structure preserves the shallow emitter (20.2 μm) everywhere except directly beneath the emitter contact. There the junction depth is greater than 5 μm, as desired, in order to shield carriers in the bulk silicon from that part of the silicon surface covered by metal where the recombination rate is high. This structure is realized by using n-base (rather than p-base) substrates and by utilizing screen-printed aluminum (rather than silver) emitter contacts. Prototype dendritic web silicon (web) cells (25 cm2 area) with efficiencies up to 13.2% have been produced. 相似文献
37.
Fournier D Halasz A Thiboutot S Ampleman G Manno D Hawari J 《Environmental science & technology》2004,38(15):4130-4133
Octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) is a recalcitrant energetic chemical that tends to accumulate in soil, close to the surface. The present study describes the aerobic biodegradability of HMX using Phanerochaete chrysosporium. When added to 7 day old static P. chrysosporium liquid cultures, HMX (600 nmol) degraded within 25 days of incubation. The removal of HMX was concomitant with the formation of transient amounts of its mono-nitroso derivative (1-NO-HMX). The latter apparently degraded via two potential routes: the first involved N-denitration followed by hydrolytic ring cleavage, and the second involved alpha-hydroxylation prior to ring cleavage. The degradation of 1-NO-HMX gave the ring-cleavage product 4-nitro-2,4-diazabutanal (NDAB), nitrite (NO2 -), nitrous oxide (N2O), and formaldehyde (HCHO). Using [14C]-HMX, we obtained 14CO2 (70% in 50 days), representing three C atoms of HMX. Incubation of real soils, contaminated with either HMX (403 micromol kg(-1)) (military base soil) or HMX (3057 micromol kg(-1)), and RDX (342 micromol kg(-1)) (ammunition soil) with the fungus led to 75 and 19.8% mineralization of HMX (liberated 14CO2), respectively, also via the intermediary formation of 1-NO-HMX. Mineralization in the latter soil increased to 35% after the addition of glucose, indicating that a fungus-based remediation process for heavily contaminated soils is promising. The present findings improve our understanding about the degradation pathway of HMX and demonstrate the utility of using the robust and versatile fungus P. chrysosporium to develop effective remediation processes for the removal of HMX. 相似文献
38.
Muhammad Ikram Mohammad Naeem Muhammad Zahoor Marlia Mohd Hanafiah Adeleke Abdulrahman Oyekanmi Noor Ul Islam Midrar Ullah Mater H. Mahnashi Amer Al Ali Naif A. Jalal Farkad Bantun Aiman M. Momenah Abdul Sadiq 《International journal of molecular sciences》2022,23(18)
The azo dye orange II is used extensively in the textile sector for coloring fabrics. High concentrations of it are released into aqueous environments through textile effluents. Therefore, its removal from textile wastewater and effluents is necessary. Herein, initially, we tested 11 bacterial strains for their capabilities in the degradation of orange II dye. It was revealed in the preliminary data that B. subtilis can more potently degrade the selected dye, which was thus used in the subsequent experiments. To achieve maximum decolorization, the experimental conditions were optimized whereby maximum degradation was achieved at: a 25 ppm dye concentration, pH 7, a temperature of 35 °C, a 1000 mg/L concentration of glucose, a 1000 mg/L urea concentration, a 666.66 mg/L NaCl concentration, an incubation period of 3 days, and with hydroquinone as a redox mediator at a concentration of 66.66 mg/L. The effects of the interaction of the operational factors were further confirmed using response surface methodology, which revealed that at optimum conditions of pH 6.45, a dye concentration of 17.07 mg/L, and an incubation time of 9.96 h at 45.38 °C, the maximum degradation of orange II can be obtained at a desirability coefficient of 1, estimated using the central composite design (CCD). To understand the underlying principles of degradation of the metabolites in the aliquot mixture at the optimized condition, the study steps were extracted and analyzed using GC-MS(Gas Chromatography Mass Spectrometry), FTIR(Fourier Transform Infrared Spectroscopy), 1H and carbon 13 NMR(Nuclear Magnetic Resonance Spectroscopy). The GC-MS pattern revealed that the original dye was degraded into o-xylene and naphthalene. Naphthalene was even obtained in a pure state through silica gel column isolation and confirmed using 1H and 13C NMR spectroscopic analysis. Phytotoxicity tests on Vigna radiata were also conducted and the results confirmed that the dye metabolites were less toxic than the parent dye. These results emphasize that B. subtilis should be used as a potential strain for the bioremediation of textile effluents containing orange II and other toxic azo dyes. 相似文献
39.
The Web has evolved into a dominant digital medium for conducting many types of online transactions such as shopping, paying
bills, making travel plans, etc. Such transactions typically involve a number of steps spanning several Web pages. For sighted
users these steps are relatively straightforward to do with graphical Web browsers. But they pose tremendous challenges for
visually impaired individuals. This is because screen readers, the dominant assistive technology used by visually impaired
users, function by speaking out the screen’s content serially. Consequently, using them for conducting transactions can cause
considerable information overload. But usually one needs to browse only a small fragment of a Web page to do a step of a transaction
(e.g., choosing an item from a search results list). Based on this observation this paper presents a model-directed transaction
framework to identify, extract and aurally render only the “relevant” page fragments in each step of a transaction. The framework
uses a process model to encode the state of the transaction and a concept model to identify the page fragments relevant for
the transaction in that state. We also present algorithms to mine such models from click stream data generated by transactions
and experimental evidence of the practical effectiveness of our models in improving user experience when conducting online
transactions with non-visual modalities. 相似文献
40.
Jalal?Basiri?Parsa Taher?Mehdi?Panah Farideh?Nabizadeh?ChianehEmail author 《Korean Journal of Chemical Engineering》2016,33(3):893-901
This study deals with the performance and modeling of the electro-coagulation process for ciprofloxacin (CIP) removal by using aluminum electrode as anode in a continuous electrochemical reactor. The initial pH, temperature, current density, time and flow rate were selected as independent variables in response surface methodology (RSM) involving a five-level central composite design (CCD), while CIP removal efficiency was considered as the response function. The result of optimization showed that the maximum amount of CIP removal efficiency (88%) presented at the optimal condition of pH=5.6, t=100min, T=25.5 °C, I=5.6mA/cm2 and V=25.9 mL/min. In addition, the mineralization of the CIP was investigated by chemical oxygen demand (COD) and total organic carbon (TOC) measurements that showed 77% COD removal and 49%TOC removal. 相似文献