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排序方式: 共有546条查询结果,搜索用时 171 毫秒
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Watermarking for intellectual property protection 总被引:1,自引:0,他引:1
A new watermarking method for intellectual property (IP) protection is presented. The proposed method uses a uniquely generated stream of bits, known as a watermark, embedded into the self-test circuit to represent ownership. This scheme can detect the ownership rights of the IP provider even when the chip has been packaged. Experimental results show the proposed embedding technique can survive synthesis, placement and routing. The experimental results are given to demonstrate the proposed method. 相似文献
3.
Juin-Hung Chen Hen-Wai Tsao 《Lightwave Technology, Journal of》1998,16(7):1137-1148
This paper presents a design method of optical frequency modulation (FM) subcarrier (with super carrier) transmission modem. The nonideal link characteristics, including laser chirping, fiber dispersion, voltage controlled oscillator (VCO) phase noise, relative intensity noise (RIN), and equivalent network model of laser diode of such a system that may bring about signal distortion are discussed first. We then propose a hierarchical methods to establish the system equivalent model. Finally this FM modem is applied to a GSM wireless system, in which multichannel signals are transmitted over fiber between radio port and basestation, and system performance is appraised by its dynamic range. It is found that optical FM subcarrier (with super carrier) transmission technique can improve the system dynamic range, compared with the intensity modulated direct detection (IMDD) method, and this is a economical and efficient method 相似文献
4.
Small-cell carcinoma (also known as oat-cell carcinoma) is a rare tumor that previously concerns the lung; small-cell carcinoma of the bladder is extremely rare (0.5% of all bladder malignancies). The Authors report here the case of a 78th years old man. Fourteen months before our observation he was submitted to a partial cystectomy for a small-cell carcinoma of the bladder cupola. There was no evidence of extra-vesical location at that moment and the patient was not submitted to any adjuvant therapy. At the moment of our observation the disease was very advanced and the patient died in a few time. The Authors discuss about the therapy of bladder small-cell carcinoma in the few cases described by the literature and about the survival of those patients. A radical surgical treatment in association with an adjuvant chemo- or radiotherapy appears as a better way to treat these patients. On account of this case the Authors agree with this choice and conclude that only a combined treatment can allow a better survival. 相似文献
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LI Tsao B Ladenheim AM Andrews CC Chiueh JL Cadet TP Su 《Canadian Metallurgical Quarterly》1998,287(1):322-331
Delta opioid peptide [D-Ala2,D-leu5]enkephalin (DADLE) can prolong organ preservation and increases myocardial tolerance to ischemia. Our study examined the protective property of DADLE against methamphetamine- (METH) induced dopaminergic terminal damage in the central nervous system. Because the neurotoxicity of METH involves reactive oxygen species, we also examined if DADLE might be an antioxidative agent in vitro. DADLE at 2 and 4 mg/kg (i.p.), given 30 min before each METH administration (5 or 10 mg/kg, i.p., four injections in a day at 2-hr intervals), dose-dependently blocked the METH-induced long-term dopamine transporter loss. The opioid antagonist naltrexone blocked this action of DADLE in both aspects of striata but tends not to affect the effects of DADLE in the nucleus accumbens. DADLE did not alter changes in body temperature induced by METH. The reduction of striatal dopaminergic content and tyrosine hydroxylase activity caused by METH, however, were not blocked by DADLE. In vitro, DADLE was approximately equipotent to glutathione in inhibiting both superoxide anion formation induced by xanthine oxidase and hydroxyl radical formation evoked by ferrous/citrate complex. DADLE was only slightly less potent than glutathione in inhibiting the iron/ascorbate-induced brain lipid peroxidation. These results suggest that DADLE can protect the terminal membranes of dopaminergic neurons against METH-induced insult but not the loss of dopaminergic content and tyrosine hydroxylase activity and that this action of DADLE might involve opioid receptors as well as the sequestration of free radical. 相似文献
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T. R. Guilinger M. J. Kelly J. R. Scully T. M. Christensen D. Ingersoll J. A. Knapp R. I. Ewing W. H. Casey S. S. Tsao 《Journal of Fusion Energy》1990,9(3):299-304
We describe several electrochemical methods used to investigate the possibility of cold fusion phenomena in palladium and titanium tritide cathodes. We performed long-term (up to 77 days) electrolysis experiments with electrochemical cells of the University of Utah type at current densities as high as 1 A/cm2, while monitoring neutron and tritium levels. With some cells, we pulsed the current to determine if neutron bursts would result. In another cell, we used titanium tritide as the cathode to determine if D-T reactions yielding neutrons would occur. In no instance were levels of neutrons or tritium significantly above background except in the titanium tritide cell where isotopic exchange, occcurring between the electrode and the electrolyte, resulted in significant tritium levels. We also combined x-ray photoelectron spectroscopy (XPS) and electrochemical hydrogen permeation experiments to determine the effectiveness of various Pd surface treatment procedures on the resultant electrochemical hydrogen absorption efficiency. Electroanalytical and thermal desorption/gas analysis techniques indicated the maximum loading of H in Pd was to a ratio of HPd=0.8. 相似文献
8.
The single-event-upset rates due to neutron-induced nuclear recoils have been calculated for Si and GaAs components using the HETC and MCNP codes and the ENDF data base for (n, p) and (n, alpha) reactions. For the same critical charge and sensitive volume, the upset rate in Si exceeds that of GaAs by a factor of about 1.7, mainly because more energy is transferred in neutron interactions with lighter Si nuclei. The upset rates due to neutrons are presented as functions of critical charge and atmospheric altitude. Upsets induced by cosmic-ray nuclei, secondary protons and neutrons are compared. 相似文献
9.
Hydrolysis of the agents used in the hydrate process for desalination is an irreversible reaction and represents an economic loss chargeable to the cost of the water produced. Rates of this reaction have been measured for the agents CH2ClF-(F-31), CHCl2F(F-21), CH3CClF2(F-142b), and CH3Br. Rates for CH3Cl and CCl2F2(F-12) have been found in the literature. An economic analysis of hydrolysis losses for all six agents has been made with the following results: F-21, F-31, F-142b and F-12 are all suitable for use in the hydrate process from the standpoint of hydrolysis; CH3Br hydrolyses much too rapidly to be economical; CH3Cl requires additional study with metal catalysts before being certified as useful. 相似文献
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