另类集成

正与使用SoC相比,用单独的晶粒或芯片来构建你的系统,也许是聪明的另类方式。SoC历史上曾代表电子业的最高境界,这是因为如果使用这些芯片,电子系统设计者就能把很多数字电路装到一小块区域中。但是,细线CMOS不适合用在模拟、电源和射频功能     

Cohesive model approach to the nucleation and propagation of cracks due to a thermal shock

This paper studies the initiation of cohesive cracks in the thermal shock problem through a variational analysis. A two-dimensional semi-infinite slab with an imposed temperature drop on its free surface is considered. Assuming that cracks are periodically distributed and orthogonal to the surface, at short times we show that the optimum is a distribution of infinitely close cohesive cracks. This leads us to introduce a homogenized effective behavior which reveals to be stable for small times, thanks to the irreversibility. At a given loading cracks with a non-cohesive part nucleate. We characterize the periodic array of these macro-cracks between which the micro-cracks remain. Finally, for longer times, the cohesive behavior converges towards that from Griffith’s evolution law. Numerical investigations complete and quantify the analytical results.     

Einfluss der Tiefkühlbehandlung auf die Maßhaltigkeit von Stahlbauteilen

For a tool steel AISI D2 (1.2379) and a case hardening steel (1.7131) the opportunity of reduction processing time and improvements of final properties and dimensional stability using deep cold treatments were investigated. Hardened blocks were subjected to various combinations of single and multiple tempering steps (520 °C and 540 °C for 1.2379 and 180 °C for 1.7131 respectively) and short- as well as long-time deep cold treatments (-90 °C, -120 °C and -150 °C). The greatest dimensional stability was achieved by deep cold treatments at the lowest temperature (-150 °C) and was independent of the deep cold treatment time.     

Unique and common mechanisms of change across cognitive and dynamic psychotherapies.

The goal of this article was to examine theoretically important mechanisms of change in psychotherapy outcome across different types of treatment. Specifically, the role of gains in self-understanding, acquisition of compensatory skills, and improvements in views of the self were examined. A pooled study database collected at the University of Pennsylvania Center for Psychotherapy Research, which includes studies conducted from 1995 to 2002 evaluating the efficacy of cognitive and psychodynamic therapies for a variety of disorders, was used. Patient samples included major depressive disorder, generalized anxiety disorder, panic disorder, borderline personality disorder, and adolescent anxiety disorders. A common assessment battery of mechanism and outcome measures was given at treatment intake, termination, and 6-month follow-up for all 184 patients. Improvements in self-understanding, compensatory skills, and views of the self were all associated with symptom change across the diverse psychotherapies. Changes in self-understanding and compensatory skills across treatment were predictive of follow-up symptom course. Changes in self-understanding demonstrated specificity of change to dynamic psychotherapy. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Modulation of the antioxidant/pro-oxidant balance,cytotoxicity and antiviral actions of grape seed extracts

Grape seed extracts (GSEs) were investigated in yeast cells harbouring defects in their antioxidant system (regarding the cellular growth and growth recovery from H₂O₂ insult). GSEs antioxidant activity was detected in wild-type and mutant strains Δcta1, Δgsh1 and Δoye2glr1, while pro-oxidant activity in Δsod1 cells was seen. Assessment of proliferation of prostate cancer PC3 and HBV-replicating HepG2 2.2.15 cells treated with GSEs has shown higher cytotoxicity of red grape seed extract (RW) than white grape seed extract (WW) subjective to dose and period of administration. No antiviral effect was detected by measuring the secreted virion particles in HepG2 2.2.15 cells treated with GSEs. The GSEs play a dual antioxidant/pro-oxidant role in vivo according with the cellular antioxidant system deficiencies and exhibit cytotoxic properties in PC3 and HepG2 2.2.15 cell lines, but no antiviral action against HBV.     

Experimental Characterization and Optimization of Hybrid FRP/RC Bridge Superstructure System

An experimental investigation was performed to assess the performance of a hybrid fiber-reinforced polymer/reinforced concrete bridge system. The full-scale laboratory specimen was representative of an 813?mm (32?in.) wide strip of a completed bridge in San Patricio County, Tex. The specimen was first subjected to static loading prior to casting the reinforced concrete deck. Displacement, strain, and acoustic emission were recorded. After completion of the nondestructive static loading a reinforced concrete deck was cast in the laboratory to represent one unit of the completed bridge. Load was statically applied with several increased load cycles until failure occurred at a load level exceeding 18 times the calculated design load. The results of the static testing indicated that the original design of the hybrid bridge was very conservative. An optimized design of the hybrid bridge was then derived. The static load testing program and the resulting optimized design are described.     

Simplified calculation of the area specific impedance for battery design

Battery design is a critical aspect of material and system development that leads to the commercialization of effective electrochemical energy storage systems. Successful modeling of battery designs relies upon accurate calculation of the area specific impedance (ASI). A simplified calculation of the ASI is presented that accounts for physical limitations without performing computationally expensive calculations. The limiting currents for transport within the electrolyte and within the intercalation materials are implemented into a linear form of the Butler-Volmer equation to calculate the interfacial impedance. Lithium-ion batteries are then designed to examine the effect of power to energy ratio on battery dimensions. A large ASI is shown to be detrimental to battery design regardless if the increase in impedance results from mass transport limitations or a reduction in electrochemical active area due to small electrode loadings. The smaller electrochemical active area does not increase the voltage losses of a battery when a constant C-rate is maintained. However, the higher ASI values from low electrode loadings require a larger separator and current collector area resulting in a greater battery volume and weight to achieve similar energy and power requirements when compared to a system with a lower ASI.     

A thin multi-ring negative liquid crystal lens enabled by high-�� dielectric material

This study is dedicated to design an liquid crystal (LC) negative lens with unequal width electrodes, which is made for a camera lens and with the aim to replace conventional negative lenses. The structure of the LC negative lens is symmetric for producing a symmetrical electric field. The unequal widths are adopted and determined inversely proportional to the slopes of the desired applied voltages at varied radial positions. There are four ring electrodes in the lens and the associated with applied different voltages. In addition, the performance of the designed LC lens is verified by the software DIMOS.2D. The special structure and the material are used to realize the designed LC lens. Moreover, a new fabrication process in the wafer level to bury bus lines is developed in order to smooth the generated electric field distribution. In addition, a high-?? dielectric layer is coated between the electrodes and the LC layer for minimizing required applied voltage. Finally, differential effects of the LC lens structure with high-?? and without high-?? are discussed based on simulation results.     

Fused ring and linking groups effect on overcharge protection for lithium-ion batteries

The derivatives of 1,3-benzodioxan (DBBD1) and 1,4-benzodioxan (DBBD2) bearing two tert-butyl groups have been synthesized as new redox shuttle additives for overcharge protection of lithium-ion batteries. Both compounds exhibit a reversible redox wave over 4 V vs Li/Li⁺ with better solubility in a commercial electrolyte (1.2 M LiPF₆ dissolved in ethylene carbonate/ethyl methyl carbonate (EC/EMC 3/7) than the di-tert-butyl-substituted 1,4-dimethoxybenzene (DDB). The electrochemical stability of DBBD1 and DBBD2 was tested under charge/discharge cycles with 100% overcharge at each cycle in MCMB/LiFePO₄ and Li₄Ti₅O₁₂/LiFePO₄ cells. DBBD2 shows significantly better performance than DBBD1 for both cell chemistries. The structural difference and reaction energies for decomposition have been studied by density functional calculations.