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81.
A Single-Cell Self-Boost (SCSB) program scheme is proposed to achieve a 1.0 V power supply operation in Ferroelectric (Fe-) NAND flash memories. The proposed SCSB scheme only self-boosts the channel voltage of the cell to which the program voltage VPGM is applied in the program-inhibit NAND string. The program disturb is well suppressed at the 1.0 V power supply voltage in the proposed program scheme. The power consumption of the Fe-NAND at VCC = 1.0 V decreases by 86% compared with the conventional floating gate (FG-) NAND at VCC = 1.8 V without the degradation of the write speed. The number of NAND chips written simultaneously in Solid-State Drives (SSD) increases by 6.7 times and the 9.3 GB/s write throughput of the Fe-NAND SSD is achieved for an enterprise application.  相似文献   
82.
Data characterizing is considered the first and main stage of the statistical analysis. Rather than characterizing each biomechanical signal through one or few global indicators, such as the mean or the root mean square, this paper suggests first to cut the scale into several fuzzy windows and to summarize the data within each window through an occurrence indicator. These indicators become the analysis variables. They can be analyzed through the multiple correspondence analysis, which shows the most discriminant variables, connections between them, empirical situation classes and correspondences between these classes and the most discriminant variables. An example is considered for arguing our point of view; it concerns characterizing and analysis of forces situated at the hand, foot and back level in a load lifting task.  相似文献   
83.
105Rh becomes a stable 105Pd after β-decay with a half-life of 35.36 h. The energies of especially strong γ-rays emitted from 105Rh are 306.1 and 318.9 keV, and the emission probabilities are evaluated to be 5.1±0.3% and 19.1±0.6% by de Frenne et al. To improve the certainty, the γ-ray emission probabilities were determined from the disintegration rate and absolute γ-ray intensities measured using a 4πβ(ppc)-γ(HPGe) coincidence apparatus with two-dimensional data-acquisition system. The results for the 306.1 and 318.9 keV γ-rays were 4.76±0.05% and 16.99±0.17%, respectively.  相似文献   
84.
Changes in air pressure during monotonic and cyclic loading are in some cases important for the behavior of unsaturated soil. For example, in order to investigate the stability of embankments and slope failure during earthquakes, it is necessary to consider the effect of the pore air or the pore gas pressure as well as the pore water pressure and the interaction between the soil and the pore fluids. In the present study, we carried out a series of monotonic and cyclic loading tests on sandy soil used for the improvement of river embankments. The effects of the initial suction, the confining pressure, and the degree of compaction under fully undrained conditions, namely, constant water and constant air shearing tests, as well as under drained conditions for both air and water, were studied. For the stress variables of the unsaturated soil, the skeleton stress was used to describe the experimental results and was defined as the difference between the total stress tensor and the average pore pressure of water and gas (Oka et al., 2010). From the monotonic and cyclic test results, we found that the stress-strain behavior of unsaturated sandy soil strongly depends on the initial suction, especially under fully undrained conditions, due to the difference in pore pressures. In the cyclic loading tests under fully undrained conditions, the mean skeleton stress decreased due to the increase in air pressure and led to the failure of the specimen in the case of a lower level of initial suction. In addition, the test results exhibited the strain rate effect on the stress-strain behavior during cyclic loading under fully undrained conditions.  相似文献   
85.
Photovoltaic generation systems must have protection devices and islanding detection devices if they are connected to utility lines of the electric power company. This is regulated in national technological requirement guidelines and the electric equipment technology standards. Islanding detection devices are installed to detect blackouts due to events such as ground faults and short circuits in utility lines. When an islanding detection device detects a power blackout, the photovoltaic generation system must be stopped immediately. It is known that islanding detection devices cannot detect islanding if induction motors are present among the loads. We investigated the influence of induction motors on islanding detection devices and found that when the frequency decreases after a utility line failure, induction motors change over to generator mode, thus compensating the active power imbalance and suppressing voltage variation. In addition, if the postfault frequency is adjusted by PLL control so as to maintain a fixed power factor, induction motors suppress this frequency change, thus extending islanding operation. It is clear from the above results that induction motors are more likely to produce islanding phenomena than static loads. © 2010 Wiley Periodicals, Inc. Electr Eng Jpn, 171(4): 8–18, 2010; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20962  相似文献   
86.
We examined and evaluated the output characteristics and the deterioration lowering factors of modules installed under various conditions (module directions and tilted angles) based on the data collected at the multi-position test facility, which was produced and installed in order to conduct evaluation using design parameters (correction coefficient). This report introduces example data and the results of our evaluation.  相似文献   
87.
We have developed an IR chopper utilizing the electro-optical effect of liquid crystals for pyroelectric sensors. This IR chopper primarily consists of liquid crystals and Si substrates with wire-grid polarizers. We have investigated theoretically the relationship between the characteristics of this IR chopper and its structure. It is confirmed that the theoretical calculations of the IR modulation degree are in approximate agreement with the experimental results. Under the condition that the IR radiation is emitted from a blackbody whose surface temperature is 150 °C, a degree of modulation of 7.4% is obtained.  相似文献   
88.
We herein describe the synthesis of fluorescent 5-(5,6-dimethoxybenzothiazol-2-yl)-2'-deoxyuridine 5'-triphosphate (d(bt)UTP) and primer extension reactions using d(bt)UTP. We also carried out primer extension reactions using the (bt)U template. B family DNA polymerases, such as KOD, Deep Vent (exo-), and 9°N(m) DNA polymerases, were effective for elongation with d(bt)UTP. Deep Vent (exo-) and KOD DNA polymerases have excellent fidelity for incorporating d(bt)UTP only at the site opposite the adenine template and only dATP when using the (bt)U template. Therefore, d(bt)UTP is an excellent fluorescent nucleotide that can be incorporated into DNA by DNA polymerases.  相似文献   
89.
The effects of illumination time, temperature, catalyst concentration, and pH on the on-line photocatalytic dehalogenation of iodinated aromatic compounds in a near-UV-illuminated titanium dioxide (anatase type) aqueous suspension were monitored via the iodine-luminol chemiluminescence (CL) reaction in a reversed micellar medium, and a new, automated, rapid, and efficient method was developed. A water-cooled, 400-W high-pressure Hg lamp was used as an internal light source. The flow procedure involved the following: (1) photocatalytic dehalogenation/degradation of the iodinated compound by the near-UV-illuminated titanium dioxide and the production of iodide species, (2) oxidation of iodide into iodine, (3) extraction of iodine into cyclohexane, (4) membrane separation of the iodine-containing organic phase from the aqueous phase, and (5) the detection of iodine using the luminol CL reaction in the reversed micellar solution of cetyltrimethylammonium chloride in 6:5 (v/v) chloroform-cyclohexane/water buffered with sodium carbonate. Results for the dehalogenation of the iodinated compounds, o-iodobenzoic acid and L-thyroxine (3,5,3',5'-tetraiodothyronine) sodium, were compared with a standard inorganic iodide solution. After establishing the optimum chemical and instrumental conditions, detection limits of 0.8 x 10(-9) and 0.2 x 10(-9) M and linear calibration graphs were obtained with dynamic ranges from 0.79 x 10(-7) to 7.9 x 10(-7) M and from 0.20 x 10(-7) to 2.0 x 10(-7) M for o-iodobenzoic acid and L-thyroxine, respectively. A precision of approximately 4% relative standard deviation (n = 6) was provided at an o-iodobenzoic acid concentration of 0.79 x 10(-7) M. The method developed was applied to the on-line determinations of iodinated aromatic compounds such as L-thyroxine sodium and iopamidol ((S)-N,N'-bis[2-hydroxy-1-(hydroxymethyl)ethyl]-5-[(2-hydroxy-1-oxopropyl)amino]-2,4,6-triiodoisophthaldiamide) in pharmaceuticals.  相似文献   
90.
Degradation of Multilayer Ceramic Capacitors with Nickel Electrodes   总被引:1,自引:0,他引:1  
The mechanism of degradation, or IR drop, of BaTiO3-based Ni-electrode chip capacitors has been studied, with special attention to the microstructure. Degradation occurred mainly at the center of the capacitors. Longer-life capacitors were obtained under conditions of low oxygen partial pressure, 10−12 atm, during sintering, and had larger grain sizes and smaller quantities of grain boundary phase. The existence of oxygen vacancies in the grain boundary phase was confirmed by cathode luminescence measurement. Double layers along the surfaces of the Ni electrodes were also related to the life of the capacitors.  相似文献   
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