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An RF LDMOS with excellent efficiency and ruggedness based on a modified CMOS process

Journal of Semiconductors 2013年第9期34卷 63-66页

作者：余庭罗玲 Institute of Semiconductors Chinese Academy of Sciences Xidian University

Two types of RF LDMOS devices, specified for application in the driver stage and output stage of a power amplifier, are designed based on a modified CMOS process. By optimizing the layout and process, the output capacitance per unit of gate width is as low as 225 fF/mm. The driver stage and output stage devices achieve an output power of 44 W with a PAE of 82% and 230 W with a PAE of 72.3%, respectively （P3aB compression） at 1 GHz. Both devices are capable of withstanding extremely severe ruggedness tests without any performance degradation. These tests are 3-5 dB overdrive, 10：1 voltage standing wave ratio mismatch load through all phase angles, and 40% drain overvoltage elevation at a working point of P3aB.

关键词： PAE ruggedness RF LDMOS CMOS output power

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Design of high reliability RF-LDMOS by suppressing the parasitic bipolar effect using enhanced p-well and double epitaxy

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Journal of Semiconductors 2015年第6期36卷 93-98页

作者：徐向明黄景丰遇寒钱文生周正良韩波王勇王鹏飞张卫 State Key Laboratory of ASIC and System School of Microelectronics Fudan University HuaHong Grace Semiconductor Manufacturing Corporation School of Computer and Information Engineering Fuyang Teachers College

A laterally diffused metal-oxide-semiconductor （LDMOS） device design with an enhanced p-well and double p-epitaxial structure is investigated for device ruggedness improvement while keeping its high device per- formance under high frequency. Based upon the device design, radio-frequency （RF） LDMOS transistors for GSM （global system for mobile communication） application have been fabricated by using 0.35/zm CMOS technolo- gies. Experimental data show that the proposed device achieves a breakdown voltage of 70 V, output power of 180 W. The RF linear gain is over 20 dB and the power added efficiency （PAE） is over 70% with the frequency of 920 MHz. In particular, it can pass the 20 ： 1 voltage standing wave ratio （VSWR） load mismatch biased at drain DC supply voltage of 32 V and output power at 10-dB gain compression point （P10dB）. The device ruggedness has been remarkably improved by using the proposed device structure.

关键词： RF power LDMOS semiconductor device ruggedness reliability

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Physicochemical bases for protein folding,dynamics,and protein-ligand binding

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Science China(Life Sciences) 2014年第5期57卷 287-302页

作者： LI HuiMin XIE YueHui LIU CiQuan LIU ShuQun School of Mathematics and Computer Science Yunnan University of Nationalities Laboratory for Conservation and Utilization of Bio-Resources & Key Laboratory for Microbial Resources of Ministry of Education Yunnan University Teaching and Research Section of Computer Department of Basic MedicalKunming Medical University Southwest Biological Diversity Laboratory Kunming Branch of Chinese Academy of Sciences Key Laboratory for Animal Genetic Diversity and Evolution of High Education in Yunnan Province

Proteins are essential parts of living organisms and participate in virtually every process within cells. As the genomlc sequences for increasing number of organisms are completed, research into how proteins can perform such a variety of functions has become much more intensive because the value of the genomic sequences relies on the accuracy of understanding the encoded gene products. Although the static three-dimensional structures of many proteins are known, the functions of proteins are ulti- mately governed by their dynamic characteristics, including the folding process, conformational fluctuations, molecular mo- tions, and protein-ligand interactions. In this review, the physicochemical principles underlying these dynamic processes are discussed in depth based on the free energy landscape （FEL） theory. Questions of why and how proteins fold into their native conformational states, why proteins are inherently dynamic, and how their dynamic personalities govern protein functions are answered. This paper will contribute to the understanding of structure-function relationship of proteins in the post-genome era of life science research.

关键词： free energy landscape entropy-enthalpy non-complementarity ruggedness driving force thermodynamics kinetics

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Quantifying the Accuracy of LiDAR-Derived DEM in Deciduous Eastern Forests of the Cumberland Plateau

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Journal of Geographic Information System 2017年第3期9卷 339-353页

作者： Marco A. Contreras Wesley Staats Jian Yiang David Parrott Associate Professor of Forest Management Department of Forestry College of Agriculture Food and Environment University of Kentucky Lexington Kentucky USA Research Assistant Department of Forestry College of Agriculture Food and Environment University of Kentucky Lexington Kentucky USA Assistant Professor of Landscape Ecology Department of Forestry College of Agriculture Food and Environment University of Kentucky Lexington Kentucky USA

Digital elevation models (DEMs) derived from light detection and ranging (LiDAR) technology are becoming the standard in representing terrain surfaces. They have numerous applications in forestry, agriculture, and natural resources. Although elevation errors are much lower than those derived from traditional methods, accuracies have been reported to decrease with terrain slope and vegetation cover. In this study, we quantified the accuracy of airborne LiDAR-derived DEM in deciduous eastern forests of the Cumberland Plateau. We measured relative elevation changes within field plots located across different slope and ruggedness classes to quantify DEM accuracy. We compared elevation change errors of DEMs derived from three LiDAR datasets: a low-density (~1.5 pts•m−2), a high-density (~40 pts•m−2), and a combined dataset. We also compared DEMs obtained by interpolating the ground points using four interpolation methods. Results indicate that mean elevation change error (MECE) increased with terrain slope and ruggedness with an average of 73.6 cm. MECE values ranged from 23.2 cm in areas with lowest slope (0% - 39%) and ruggedness (0% - 28%) classes to 145.5 cm in areas with highest slope (50% - 103%) and ruggedness (46% - 103%) classes. We found no significant differences among interpolation methods or LiDAR datasets;the latter of which indicates that similar accuracy levels can be achieved with the low-density datasets.

关键词： Elevation Change Error Terrain Relief ruggedness and Slope Remote Sensing

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Development and Validation of New RP-HPLC Method for the Estimation of Alfuzosin Hydrochloride in Bulk and Tablet Dosage Form

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American Journal of Analytical Chemistry 2013年第1期4卷 34-43页

作者： Vandana P. Patil Subhash J. Devdhe Suwarna H. Kale Vijay J. Nagmoti Sadanand D. Kurhade Yuvraj R. Girbane Mahesh T. Gaikwad Yash Institute of Pharmacy Aurangabad India

A reverse phase high performance liquid chromatographic method (HPLC) has been developed for the estimation of Alfuzosin hydrochloride (ALH) in the pharmaceutical formulation using RP-C18 column. The mobile phase (Tetrahydrofuran, Acetonitrile and buffer (pH 3.50) was pumped at a flow rate of 1.5 ml/min in the ratio of 1:20:80 and the eluents were monitored at 254.0 nm. Linearity was obtained in the concentration range of 80 - 120 μg/mL for ALH. The method was statistically validated and RSD was found to be less than 2% indicating high degree of accuracy and precision of the proposed HPLC method. Due to its simplicity, rapidness, high precision and accuracy, the proposed HPLC method may be used for determination of Alfuzosin hydrochloride in bulk drugs and in pharmaceutical dosage form.

关键词： Alfuzosin HCl RP-HPLC Linearity Precision Accuracy Robustness ruggedness

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