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1.
The increasing architecture complexity of data converters makes it necessary to use behavioral models to simulate their electrical performance and to determine their relevant data features. For this purpose, a specific data converter simulation environment has been developed which allows designers to perform time-domain behavioral simulations of pipelined analog to digital converters (ADCs). All the necessary blocks of this specific simulation environment have been implemented using the popular Matlab simulink environment. The purpose of this paper is to present the behavioral models of these blocks taking into account most of the pipelined ADC non-idealities, such as sampling jitter, noise, and operational amplifier parameters (white noise, finite DC gain, finite bandwidth, slew rate, and saturation voltages). Simulations, using a 10-bit pipelined ADC as a design example, show that in addition to the limits analysis and the electrical features extraction, designers can determine the specifications of the basic blocks in order to meet the given data converter requirements. 相似文献
2.
Kouda Souhil Dibi Zohir Barra Samir Dendouga Abdelghani Meddour Fay?al 《International Journal of Control, Automation and Systems》2011,9(1):197-202
This paper presents a design of a smart humidity sensor. First we begin by the modeling of a Capacitive MEMS-based humidity
sensor. Using neuronal networks and Matlab environment to accurately express the non-linearity, the hysteresis effect and
the cross sensitivity of the output humidity sensor used. We have done the training to create an analytical model CHS “Capacitive
Humidity Sensor”. Because our sensor is a capacitive type, the obtained model on PSPICE reflects the humidity variation by
a capacity variation, which is a passive magnitude; it requires a conversion to an active magnitude, why we realize a conversion
capacity/voltage using a switched capacitor circuit SCC. In a second step a linearization, by Matlab program, is applied to
CHS response whose goal is to create a database for an element of correction “CORRECTOR”. After that we use the bias matrix
and the weights matrix obtained by training to establish the CHS model and the CORRECTOR model on PSPICE simulator, where
the output of the first is identical to the output of the CHS and the last correct its nonlinear response, and eliminate its
hysteresis effect and cross sensitivity. The three blocks; CHS model, CORRECTOR model and the capacity/voltage converter,
represent the smart sensor. 相似文献
3.
K. Kakushima K. Okamoto M. Kouda T. Kawanago P. Ahmet K. Tsutsui T. Hattori 《Microelectronics Reliability》2010,50(3):356-359
The chemical bonding states and electrical characteristics of SrO capped La2O3/CeOx gate dielectric have been examined. Angle-resolved X-ray photoelectron spectroscopy measurement has revealed that Sr atoms diffuse into silicate layer to form SrLa-silicate after annealing. Owing to the incorporation of Sr atoms into silicate layer, a transistor operation with an equivalent oxide thickness (EOT) below 0.5 nm has been demonstrated. A strongly degraded effective electron mobility of 78 cm2/V s at 1 MV/cm has been obtained, which fit well with the general trend in small EOT range below 1 nm. Although process optimization is needed to improve the performance of transistors, Sr capping technique can be useful for EOT scaling. 相似文献
4.
S. Kouda K. Kimura H. Nakamura H. Ochiishi T. Nakashima S. Morinobu 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》1999,420(3):380
For the study of parity mixing in the compound states, a method to measure the longitudinal analyzing power Az of the isobaric analog resonance (IAR) as a function of energy in the proton elastic scattering is discussed. A thick target is used and energy loss of the protons in the target is utilized to measure the energy dependence. The energy resolution is presented and the sources of the systematic errors in Az are discussed together with the way of their elimination. The method has been shown to be quite efficient for deriving both the transverse and the longitudinal analyzing powers. The measurement of Az for the s-wave IAR at Ecm=5.86 MeV in 90Zr(p,p) and the analysis to derive PNC matrix elements are described. 相似文献
5.
S Tatsumi K Miyamoto T Kouda K Motonaga K Katai I Ohkido K Morita H Segawa Y Tani H Yamamoto Y Taketani E Takeda 《Canadian Metallurgical Quarterly》1998,273(44):28568-28575
We have isolated three unique NaPi-2-related protein cDNAs (NaPi-2alpha, NaPi-2beta, and NaPi-2gamma) from a rat kidney library. NaPi-2alpha cDNA encodes 337 amino acids which have high homology to the N-terminal half of NaPi-2 containing 3 transmembrane domains. NaPi-2beta encodes 327 amino acids which are identical to the N-terminal region of NaPi-2 containing 4 transmembrane domains, whereas the 146 amino acids in the C-terminal region are completely different. In contrast, NaPi-2gamma encodes 268 amino acids which are identical to the C-terminal half of NaPi-2. An analysis of phage and cosmid clones indicated that the three related proteins were produced by alternative splicing in the NaPi-2 gene. In a rabbit reticulocyte lysate system, NaPi-2 alpha, beta, and gamma were found to be 36, 36, and 29 kDa amino acid polypeptides, respectively. NaPi-2alpha and NaPi-2gamma were glycosylated and revealed to be 45- and 35-kDa proteins, respectively. In isolated brush-border membrane vesicles, an N-terminal antibody was reacted with 45- and 40-kDa, and a C-terminal antibody was reacted with 37-kDa protein. The sizes of these proteins corresponded to those in glycosylated forms. A functional analysis demonstrated that NaPi-2gamma and -2alpha markedly inhibited NaPi-2 activity in Xenopus oocytes. The results suggest that these short isoforms may function as a dominant negative inhibitor of the full-length transporter. 相似文献
6.
Technetium-99m-diethylenetriaminepentaacetic acid-galactosyl-human serum albumin (GSA) is a new scintigraphic agent that binds specifically to asialoglycoprotein receptors on hepatocytes, and can be used to evaluate hepatic function. Asialoglycoprotein receptor is a hepatocellular membrane receptor responsible for the endocytosis of asialoglycoproteins, and the function of this receptor is affected in various disease states. The aim of this study was to investigate GSA uptake per hepatocyte in the convalescent stage from hepatic damage. METHODS: We used rats with dimethylnitrosamine (DMN)-induced hepatic injury and rats with recombinant human hepatocyte growth factor (rhHGF) stimulation. Plasma clearance of GSA and the number of hepatocytes in whole liver were calculated. RESULTS: In the DMN-treated rats, the total number of hepatocytes and GSA plasma clearance were reduced significantly at 3 wk after the final administration of DMN. However, calculated GSA uptake per individual hepatocyte was significantly greater by 53.2% than in the normal controls. The area of hepatic nucleus was also significantly greater than in the normal controls. In the rhHGF-treated rats, an increase in the total number of hepatocytes was not demonstrated on the final day of rhHGF administration (Day 4). However, calculated GSA uptake per hepatocyte was significantly greater (59%) than in the controls. CONCLUSION: Augmented GSA uptake per hepatocyte during the convalescent stage after hepatic injury suggests a cellular compensation to the decreased number of hepatocyte. This mechanism may be caused by the secretion of some hepatotropic factors such as HGF. 相似文献
7.
Recently, due to a rapid increase of demand for air conditioning in summer, peak power demand is becoming increasingly acute. Therefore, the load factor has a tendency to drop every year. The drop of the load factor is leading to a drop in the utilization factor of the power facilities and an increase in the cost of installation. In this paper, we propose an energy storage system for peak‐cut of power demand, in which we use large‐capacity electric double‐layer capacitors. This energy storage system has some distinctive characteristics, including long life span, maintenance‐free operation, preservation of environment, high efficiency at charge/discharge, and so on. This paper deals with the circuit arrangement of the proposed energy storage system, the charge equalization method of the capacitors, and the control method of the converter at charge/discharge. Finally, the operating characteristics of this system are evaluated by simulation analysis. © 2000 Scripta Technica, Electr Eng Jpn, 133(3): 83‐92, 2000 相似文献
8.
A model for the structure and growth of carbon nanofibers synthesized by the CVD method using nickel as a catalyst 总被引:2,自引:0,他引:2
Carbon nanofibers were synthesized at 450-800 °C by the catalytic CVD method using alumina plate-supported nickel as catalyst and acetylene as carbon source. It was found that Ni/alumina catalyst exhibited a large catalytic effect on the growth of carbon nanofibers at the temperatures between 550 and 700 °C. TEM observation revealed that most of the carbon nanofibers synthesized at 550 °C had a coil-like shape, and many thick platelet nanofibers were found in the product at 700 °C. A growth model was proposed to explain the structural diversity of the carbon nanofibers. Although the carbon nanofibers showed low crystallinity, they can be easily graphitized at 2500 °C. 相似文献
9.
Hirao Kohno Katsuyasu Kouda Rikio Tokunaga Yoshiaki Sonoda 《European Food Research and Technology》2007,225(5-6):913-920
Herbal teas have become popular as alternatives to caffeinated beverages during past two decades. However, toxicological studies
of herbal teas have been limited and the safety of herbal teas thus remains unknown. We focused on the estrogenic activities
of herbal teas since some of their ingredients are similar to those used in herbal remedies for menopause relief and therefore
contain phytoestrogens. To investigate the potential estrogenic activity of extracts prepared from herbal tea mixtures commercially
available and to provide useful information for the safety assessment of those products, we initially screened the estrogenic
activity in extracts of 15 different herbal teas by an assay using recombinant yeast cells expressing the human estrogen receptor
(YES). A distinct estrogenic activity was thus detected in the ethanolic extracts from four herbal tea mixtures. Licorice
root was specified as a ingredient responsible for the estrogenic activity in those extracts. In contrast, the aqueous extracts
of all herbal tea mixtures we tested exhibited distinct estrogenic activity in YES, thus suggesting the existence of various
ingredients that contain estrogenic constituents extractable with water. Among them, the extract of peppermint tea exhibited
the highest estrogenic activity. The estrogenic activity in extracts of herbal tea mixtures and specified ingredients were
thereafter confirmed by a reporter assay system using transiently transfected HEK293 cells. 相似文献
10.
Sawai H Wada M Kouda T Nakamura Ozaki A 《Chembiochem : a European journal of chemical biology》2006,7(4):605-611
5'-pACUG tetraribonucleotides containing 2'-5' or 3'-5' linkages self-condensed on 2'-5'- or 3'-5'-linked complementary decaribonucleotide (5'-CAGUCAGUCA) templates. CD and UV melting studies showed that helix formation took place in all four possible combinations of linkage isomers of the substrate tetramer and the template decamer under the ligation conditions. The hybridization ability followed the order: [3'-5' tetramer with 3'-5' decamer] > [2'-5' tetramer with 3'-5' decamer] > [2'-5' tetramer with 2'-5' decamer] > or = [3'-5' tetramer with 2'-5' decamer]. Each tetramer condensed on the complementary decaribonucletide template to form the corresponding octamer, but the ligation efficiency varied considerably, depending on the types of linkage in the tetramer substrate and the template decamer. The yields of the octamers obtained by the template-directed ligation followed the order: [2'-5' substrate: 2'-5' template] > [3'-5':3'-5'] > [2'-5':3'-5'] > [3'-5':2'-5']. The results demonstrate that a homo-linkage system is preferable for the template-directed synthesis of RNA. The resulting linkage of the octamer formed from the 2'-5'-linked substrate and the 2'-5'-linked template is mainly 2'-5'. 相似文献