A Compact Four-Quadrant Floating-Gate MOS Multiplier

A compact, four-quadrant analog CMOS multiplier featuring wide dynamic range is presented. The capacitive voltage division obtained by the use of Floating-Gate MOS (FGMOS) transistors, and an accurate wide-swing current mirror based on active bootstrapping, allow a wide input range, low harmonic distortion, and high linearity. Simulation and measurement results for a 0.8 μm CMOS prototype demonstrate the validity of the proposed approach.     

Stochastic analysis of crude oil procurement and processing under uncertain demand for bunker fuel oil

Bunker fuel oil (ifo), one of the products of petroleum refining, has a strong impact in the production process because it drives the availability of heavy residues that depend on the crude quality. A simplified stochastic model for the Administración Nacional de Combustibles Alcohol y Portland refinery, based on the uncertainty of the demand for ifo, is proposed for comparison with the current approach of deterministic demand. In this model, the benefits of the production process are maximized, taking decisions on the more suitable raw material, intermediate products and final blends in order to fulfill quality and demand requirements of final products. A specific case is analyzed where the maximum benefit is achieved when the most expensive crude quality is purchased, due to a lack of incentive to produce extra amounts of heavy fuel oil that must be exported at a non‐attractive price. Results are compared with the solution of a deterministic model with mean demand. In addition, the stochastic model solution depicts how the refinery should operate for each scenario of ifo demand.     

Flammability tests, 1975: A review

The author identifies the numerous tests designed to describe the flammability characteristics of materials and discusses some of the more widely used ones. Note: The author now holds the title Research Professor in the Institute of Chemical Biology of the University of San Francisco.     

Characterization of coal ash with X-ray photoelectron spectroscopy (ESCA)

A characterization study of coal ash samples from Southern Brazil (Charqueadas, Candiota and Leão Butiá) and from the U.S.A. (Pennsylvania bituminous, Illinois sub-bituminous and North Dakota lignite) has been performed with X-ray photoelectron spectroscopy (ESCA). Qualitative as well as quantitative data are presented. the technique also gives information on the oxidation state of several elements detected. the results are in agreement with existing data. The methodology used to extend ESCA, usually considered a surface/semisurface technique, to the analysis of bulk samples is given in some detail.     

Morphology of poly(hexamethylene oxide) fractions

The supermolecular structure of crystallised molecular weight fractions of poly(hexa-methylene oxide), covering the molecular weight range (M) 4.5. × 10³ to 8. 5 × 10⁴, was studied by polarised light microscopy and small angle light scattering. Different forms were observed as a function of molecular weight and crystallisation temperatures. Perfect spherulites are formed after rapid crystallisation, and these forms deteriorate as both the molecular weight and crystallisation temperature increase. The morphology in the isothermal crystallisation region corresponds to an intermediate state which represents a transition from spherulites to hedrites.     

Allelic loss on chromosome 18q as a prognostic marker in stage II colorectal cancer

The aim of the study was to elucidate the vasodilatory mechanism due to Cu2+ by assessing nitric oxide (NO) production as determined by NOx (NO, NO2-, and NO3-) that is released from human pulmonary arterial endothelial cell (HPAEC) monolayers using a NO chemiluminescence analyzer, and also to assess Ca2+ movement using 45Ca and fura 2 in HPAEC. Cu2+ (10(-6)-10(-4) M) significantly increased NO production in a dose-dependent manner when extracellular Ca2+ was present. 45Ca influx into the adherent cells was dose-dependently enhanced by Cu(2+) (10(-6)-10(-4) M), but not by Mn(2+), Zn(2+) or Fe(2+). [Ca2+]i, measured by monitoring the fluorescence changes of fura 2, was significantly elevated in the presence of Cu2+. The increase in [Ca2+]i induced by Cu2+ was inhibited by either diethyldithiocarbamate (DDC) or the depletion of extracellular Ca2+. The dihydropyridine receptor agonist, BayK8644, significantly attenuated the Cu2+-induced increase in [Ca2+]i in a dose dependent manner and nitrendipine or nifedipine, the dihydropyridine receptor antagonists, dose-dependently inhibited a Cu2+-induced increase in [Ca2+]i. These results suggest that Cu2+ activates eNOS through the mechanism of [Ca2+]i elevation due to Ca2+ influx into HPAEC and that the Cu2+-induced [Ca2+]i elevation in HPAEC is likely due to activation of the dihydropyridine-like receptors.     

A simple and effective pipe elbow element—some nonlinear capabilities

In some earlier communications we presented the formulation of a simple pipe elbow element for linear analysis. In this paper we extend this formulation to include some nonlinear effects. Elastic-plastic conditions can be modeled, and some kinematic nonlinearities (due to large displacement beam behavior) can also be represented. The results of some sample solutions are given to illustrate the use of the element.     

Attitudes of schizophrenics and normals toward success and failure.

The purpose of this study was to test the hypothesis that schizophrenics, as compared with normals, are relatively more highly motivated to avoid failure than to achieve success. A total of 291 Ss, including 136 hospitalized male schizophrenics, 103 normals, and--as a contrast group--52 neurotics, were administered the Success-Failure Inventory (SFI), a 22-item True-False instrument designed to assess attitudes toward success attainment and failure avoidance. As predicted, the schizophrenic samples manifested greater relative failure avoidance than the normals. Further, active schizophrenics evidenced greater relative failure avoidance than did remitted schizophrenics. Remitted schizophrenics and neurotics were not significantly different. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

对DRAM结构中影响良率的缺陷进行监控

与上一代设计规则相比，亚100nm设计规则DRAM的开发和制造面临着前所未有的挑战。按照新型设计概念，由于器件结构不断缩小，其外形特征的深．宽比增大，这样就给工艺控制增加了难度。因此要求寻找一种能够对带状缺陷和孔洞缺陷进行可靠检测的高深．宽比（HAR）检测方法。另外，由于缺陷尺寸接近小型特征尺寸，许多从前认为不那么严重的缺陷如今变得极具损害力。因而缺陷检测和良率控制技术的改良成为加速开发并实现批量生产的基础。