InxAl1 –xN Solid Solutions: Composition Stability Issues

Semiconductors - The phase diagrams of the InxAl1 –xN solid solutions and conditions for their growth by magnetron sputtering and molecular beam and metalorganic vapor phase epitaxy are...     

Thermal Conductivity in Bi1−x Sb x Solid Solutions

Bi_1?x Sb _x solid solutions have attracted much attention as promising low-temperature thermoelectric materials. Previously, we observed distinct extrema in the isotherms of the transport and mechanical properties of polycrystalline Bi_1?x Sb _x and attributed their presence to the transition from diluted to concentrated solid solutions and to the reconstruction of the energy band structure under increasing Sb concentration. The goal of the present work is a detailed study of the concentration dependences of the thermal conductivity λ for Bi_1?x Sb _x polycrystalline solid solutions (x = 0 to 0.09) in the temperature range of 170 K to 300 K. It is established that the λ(x) dependences exhibit a nonmonotonic behavior: in certain concentration ranges an anomalous increase in λ with increasing x is observed. It is shown that the concentration dependences of the thermoelectric figure of merit calculated on the basis of the measured λ values are also nonmonotonic. The obtained data represent additional evidence in favor of our assumptions stated earlier about a significant effect of electronic phase transitions observed in Bi_1?x Sb _x solid solutions on the concentration dependences of their thermoelectric properties. These results should be taken into account when developing new Bi_1?x Sb _x -based materials.     

The Growth of InAsxSb1 –x Solid Solutions on Misoriented GaAs(001) Substrates by Molecular-Beam Epitaxy

Semiconductors - The effect of a substrate misorientation degree from a singular face on the composition and morphology of layers of InAsxSb1 –x solid solutions obtained by molecular-beam...     

Effects of Doping of Lead Sulfide with Silver on the Lattice and Optical Properties of Pb1 –xAgxS Solid Solutions

Semiconductors - Single-phase cubic Pb1 –xAgxS limited solid solutions based on PbS with a metal sublattice doped with Ag are produced. The maximal relative content of Ag in the Pb1...     

Sub-1V CMOS Voltage Reference Based on Weighted Vgs

提出了一种新型CMOS恒压源的制作方案,它基于nMOS和pMOS的饱和区栅源电压随温度变化权重不同的原理,将两者做相关运算,得到零温度系数的恒压源.该电压源没有采用二极管和寄生三极管,并用SMIC 0.18μm数模混合工艺模型参数仿真并制造.测试结果表明,温度系数达到了44ppm/℃,PSRR为-46dB,650mV以上的电源电压就可以完全正常工作.芯片面积约为0.05mm2.     

Thermoelectric Properties of Bi2 –xLuxTe2.7Se0.3 Solid Solutions

Semiconductors - The thermoelectric properties of compounds based on Bi2 –xLuxTe2.7Se0.3 solid solutions with x = 0, 0.05, 0.1, and 0.2 are studied. The samples for investigations are...     

Thermoelectric Properties of Yb1−x (Er,Lu) x Al3 Solid Solutions

Ytterbium trialuminide (YbAl₃) has one of the largest thermoelectric power factors of known materials below room temperature, making it a material of interest for low-temperature thermoelectric devices. However, the high thermal conductivity, which is due to a combination of a large electronic thermal conductivity and a moderately large lattice thermal conductivity, is detrimental to the figure of merit. Substitution of different atoms on the Yb site was performed in order to assess their ability to favorably alter the electronic structure and/or reduce the lattice thermal conductivity. We have synthesized and studied the thermoelectric properties of the solid solutions of YbAl₃ with ErAl₃ and LuAl₃. Results for electrical conductivity, thermal conductivity, and Seebeck coefficient for several of these solid solutions over the temperature range of 80 K to 300 K are reported. Although most substituted samples are driven toward a metallic state, we find that for some compositions the figure of merit is enhanced relative to pure YbAl₃.     

Image Encrption Based on a 1—D Joint Transform Correlator

A method for image encryption using a 1-D joint transform correlator is described.By use of line functions,a 2-D object is encrypted first in one direction,then in the perpendicular direction.The principle of the method and experimental results are given.     

Blind Equalization Based on Evolution Strategies

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Waveguide Prism Based on Porous Silicon

The fabrication of the oxidized porous silicon waveguide prism is reported by selectively electrochemical anodisation process. The direction changes of light beams in TE and TM polarization out of this waveguide prism were respectively measured,and the experimental results were analyzed.     

Home Gateway Based on Telecom Networks

Facing the fast development ofhome and individualcommunication, people poststronger demands for diversifiedcommunications, for instance, data andmultimedia applications and homenetworks. With the extensive invading ofITto the electric home applianceindustry, the exchange and compatibilityofdata between the two industriesbecome the hot spot for study.The current SmallOffice Home Office(SOHO)/Home router, cable modem, andDSLmodem have provided diversifiedcommunication access methods, andcom…     

Substitution Solid Solutions FeGa3−x E x and Their Thermoelectric Properties

In this study we performed substitution experiments on the gallium site of the intermetallic semiconductor FeGa₃, to adjust the charge carrier concentration, and determined the thermoelectric (TE) properties of the resulting products. Isoelectronic species aluminium and indium, hole-doping zinc, and electron-doping germanium were chosen to find suitable substituent elements. The samples FeGa_3?x E _x (E = Al, In, Zn, Ge; x = 0.03, 0.05, 0.06, 0.10, 0.20) were prepared by liquid–solid–reaction with subsequent spark plasma sintering treatment. X-ray diffraction, metallographic, and microstructure analysis were used to determine chemical composition and to evaluate the suitability of the substitution element. For solid solutions FeGa_3?x Al _x and FeGa_3?x In _x the substitution concentrations were very low (x ≤ 0.02) and did not improve the TE properties of FeGa₃. The samples FeGa_3?x Zn _x had the expected p-type behaviour and slightly lower thermal conductivity than the binary compound. A substantial increase in the TE figure of merit was achieved for the solid solution FeGa_3?x Ge _x for which transition from semiconducting to metal-like behaviour was observed, with an additional decrease of thermal conductivity. The maximum ZT value of 0.21 was achieved for the composition FeGa_2.80Ge_0.20.     

Impedance Characteristics of γ-Irradiated (TlGaSe2)1 –x(TlInS2)x Solid Solutions

Semiconductors - Charge transport in (TlGaSe2)1 –x(TlInS2)x solid solutions in the frequency range of 20–106 Hz before and after γ irradiation is studied using...     

Parameter Optimization Based on GA and HFSS

A new project based on genetic algorithm (GA) and high frequency simulation software (HFSS) is proposed to optimize microwave passive devices effectively. This project is realized with a general program named as optimization program. The program is compiled by Matlab and the macro language of HFSS which is a fast and effective way to accomplish tasks. In the paper, two examples are used to show the pro/ect‘s feasibility.     

User Authentication Schemes Based on Smart Cards

1IntroductionWiththedevelOPmentofintemeUIntranetlExtrAnct,thesecurityofnetWorkshasbecomeaseriousProblem.Nowadays,thewoadabouttheirsensihveinfonnation'ssecurityhasmademanycomparesandunitShesitatetoconnecttheirPrivatenetworkstOhitemet.AlthoughFirewallshavebeenusedtOresistthevariousattacksfromexternal,somesecurityProblemsremainopen.Forexample,theSeCurityofuserauthenticationis,oneoftheimportantsecuritytopics.Themostpopularuserauthenticationismaybethepasswordauthenticationscheme.Inthesekind…     

Visual Information Processing Based on Qualitative Mapping

1 IntroductionVisionis a most i mportant feeling modefor human be-ings and mass of ani mals.Many science andtechnical work-ers of varies of subjects have done rich research on visualinformation processing on different levels and nowit hasdeveloped into a …     

Target Localization Based on Angle of Arrivals

Mobile location using angle of arrival （AOA） measurements has received considerable attention. This paper presents an approximation of maximum likelihood estimator （MLE） for localizing a source based on AOA measurements. By introducing an intermediate variable, the nonlinear equations relating AOA estimates can be transformed into a set of equations which are linear in the unknown parameters. It is an approximate realization of the MLE. Simulations show that the proposed algorithm outperforms the previous contribution.