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71.
With technology node shrinking, the susceptibility of a single chip to soft errors increases. Hence, the critical charge (Qcrit) of circuit decreases and this decrease is expected to continue with further technology scaling. In this paper previous hardened latch circuits are analyzed and it is found that previous designs offer limited protection against soft error especially for soft error caused by high energy particles and not all the nodes are under soft error protection. Therefore, in this paper we propose a low cost hardened latch design in 45 nm CMOS technology with full protection for all internal nodes as well as output node against soft error. Moreover, the proposed hardened approach is technology independent. Compared to previous hardened latch designs, the proposed design reduces cost in terms of power delay product (PDP) 59% on average.  相似文献   
72.
Personalization is a key aspect of biophysical models in order to impact clinical practice. In this paper, we propose a personalization method of electromechanical models of the heart from cine-MR images based on the adjoint method. After estimation of electrophysiological parameters, the cardiac motion is estimated based on a proactive electromechanical model. Then cardiac contractilities on two or three regions are estimated by minimizing the discrepancy between measured and simulation motion. Evaluation of the method on three patients with infarcted or dilated myocardium is provided.  相似文献   
73.
Zitz.  K 《世界电信》1999,12(7):35-38
基于本地多点分配系统(LMDS)技术的宽带无线网络方案使交换网在接入技术容量方面产生了飞跃,并在本地环路中引入了具有竞争实力的“第三方力量”本了网垄断无疑是LMDS发展的最后障碍,政策和管制是该技术发展面临的最严峻挑战。  相似文献   
74.
Two new bipolar host molecules composed of hole‐transporting carbazole and electron‐transporting cyano ( CzFCN ) or oxadiazole ( CzFOxa )‐substituted fluorenes are synthesized and characterized. The non‐conjugated connections, via an sp3‐hybridized carbon, effectively block the electronic interactions between electron‐donating and ‐accepting moieties, giving CzFCN and CzFOxa bipolar charge transport features with balanced mobilities (10?5 to 10?6 cm2 V?1 s?1). The meta–meta configuration of the fluorene‐based acceptors allows the bipolar hosts to retain relatively high triplet energies [ET = 2.70 eV ( CzFOxa ) and 2. 86 eV ( CzFCN )], which are sufficiently high for hosting blue phosphor. Using a common device structure – ITO/PEDOT:PSS/DTAF/TCTA/host:10% dopants (from blue to red)/DPPS/LiF/Al – highly efficient electrophosphorescent devices are successfully achieved. CzFCN ‐based devices demonstrate better performance characteristics, with maximum ηext of 15.1%, 17.9%, 17.4%, 18%, and 20% for blue (FIrpic), green [(PPy)2Ir(acac)], yellowish‐green [m‐(Tpm)2Ir(acac)], yellow [(Bt)2Ir(acac)], and red [Os(bpftz)2(PPhMe2)2, OS1], respectively. In addition, combining yellowish‐green m‐(Tpm)2Ir(acac) with a blue emitter (FIrpic) and a red emitter (OS1) within a single emitting layer hosted by bipolar CzFCN , three‐color electrophosphorescent WOLEDs with high efficiencies (17.3%, 33.4 cd A?1, 30 lm W ?1), high color stability, and high color‐rendering index (CRI) of 89.7 can also be realized.  相似文献   
75.
Switching of the luminescence properties of molecular materials in response to mechanical stimulation is of fundamental interest and also has a range of potential applications. Herein, a water‐soluble mechanochromic luminescent pyrene derivative having two hydrophilic dendrons is reported. This pyrene derivative is the first example of a mechanochromic luminescent organic compound that responds to relative humidity. Mechanical stimulation (grinding) of this pyrene derivative in the solid state results in a change of the photoluminescence from yellow to green. Subsequent exposure to water vapor induces recovery of the initial yellow photoluminescence. The color change is reversible through at least ten cycles. It is also demonstrated that this compound can be applied as a mechano‐sensing material in frictional wear testing for grease, owing to its immiscibility in non‐polar solvents and its non‐crystalline behavior. Transmission electron microscope and atomic force microscope observations of samples prepared from dilute aqueous solutions of the pyrene derivative on suitable substrates, together with dynamic light scattering measurements for the compound in aqueous solution, indicate that this amphiphilic dumbbell‐shaped molecule forms micelles in water.  相似文献   
76.
Silk is a protein fiber used to weave fabrics and as a biomaterial in medical applications. Recently, genetically modified silks have been produced from transgenic silkworms. In the present study, transgenic silkworms for the mass production of three colors of fluorescent silks, (green, red, and orange) are generated using a vector originating from the fibroin H chain gene and a classical breeding method. The suitability of the recombinant silks for making fabrics is investigated by harvesting large amounts of the cocoons, obtained from rearing over 20 thousand silkworms. The application of low temperature and a weakly alkaline solution for cooking and reeling enables the production of silk fiber without loss of color. The maximum strain tolerated and Young's modulus of the fluorescent silks are similar to those of ordinary silk, although the maximum stress value of the recombinant silk is slightly lower than that of the control. Fabrics with fluorescent color are demonstrated using the recombinant silk, with the color persisting for over two years. The results indicate that large amounts of genetically modified silk can be made by transgenic silkworms, and the silk is applicable as functional silk fiber for making fabrics and for use in medical applications.  相似文献   
77.
78.
A Group 3 error-free facsimile terminal for use in an analog cellular network has been developed. This facsimile terminal is provided with the International Telecommunication Union (ITU-T, formerly CCITT) T.30 recommendation protocol and an adaptive error control scheme (AECS) for Group 3 communication and error-free communication. The AECS monitors the channel conditions and selects the optimum error correction code. The ITU-T V.27ter is used as the modulation method and the transmission rate is 4800 bps. This system is compatible with the modified Huffman (MH), modified READ (MR), and modified modified READ (MMR) image data compression codes. The average communication time of this facsimile terminal is 40 s per page while moving through the analog cellular network  相似文献   
79.
A new configuration based on the polarization-mismatching scheme with time delay for efficient frequency tripling conversion is proposed in this paper. The calculated results showed that the requirement for the efficient frequency tripling conversion of a 1-ps laser pulse is not only the optimization of peak intensity of the second-harmonic pulse, but also the optimization of the pulse duration ratio and temporal difference between the o-polarization second-harmonic pulse and the e-polarization first-harmonic pulse due to group-velocity mismatch among the interacting pulses. With the proposed scheme the group velocity mismatch can be compensated. Overall energy conversion efficiency increases from 55% to 75% under the optimized conditions at the intensity of 6 GW/cm2. The temporal shape of the third-harmonic pulse with 1 ps pulse duration has no subpulses. The optimization of the efficient frequency tripling conversion for intensities of over 75 GW/cm2 is also described. The results showed that the maximum tripling energy conversion efficiency is close to 80% with the optimized doubler and tripler  相似文献   
80.
Catalyst (copper-coated zeolite catalyst, i.e., Cu-ZSM-5) was used to enhance NOx removal plasma chemical reactions. Two kinds of hydrocarbons (2-propane-1-ol, 2-propanol) were added to the synthesized flue gas before the nonthermal plasma process, and their effects on NOx removal characteristics were investigated. Enhancement effects of NOx removal by the nonthermal plasma process with hydrocarbons as the additives were confirmed. Usually, the catalyst's working temperature is much higher than the room temperature. A catalytic reactor was installed after the plasma reactor. Catalytic effects on NOx removal characteristics disappeared when the synthesized flue gas temperature was increased (~250°C). When the synthesized flue gas temperature was at room temperature, about 90% NO x removal efficiency was realized with a combination of hydrocarbons, the catalytic reactor, and the pulsed discharge plasma  相似文献   
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