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1.
Presents design, implementation, and measurement of a three-dimensional (3-D)-deployed RF front-end system-on-package (SOP) in a standard multi-layer low temperature co-fired ceramic (LTCC) technology. A compact 14 GHz GaAs MESFET-based transmitter module integrated with an embedded bandpass filter was built on LTCC 951AT tapes. The up-converter MMIC integrated with a voltage controlled oscillator (VCO) exhibits a measured up-conversion gain of 15 dB and an IIP3 of 15 dBm, while the power amplifier (PA) MMIC shows a measured gain of 31 dB and a 1-dB compression output power of 26 dBm at 14 GHz. Both MMICs were integrated on a compact LTCC module where an embedded front-end band pass filter (BPF) with a measured insertion loss of 3 dB at 14.25 GHz was integrated. The transmitter module is compact in size (400 /spl times/ 310 /spl times/ 35.2 mil/sup 3/), however it demonstrated an overall up-conversion gain of 41 dB, and available data rate of 32 Mbps with adjacent channel power ratio (ACPR) of 42 dB. These results suggest the feasibility of building highly SOP integrated RF front ends for microwave and millimeter wave applications.  相似文献   
2.
The aim of this paper is to analyze the feasibility of ultrathin packages through the electrical qualification of the technological process used, i.e. mechanical lapping. It considers polysilicon bipolar transistors which thickness can reach values lower than 10 μm. Forward mode and reverse mode characterizations show no significant degradation of pertinent characteristics, thus allowing to find applications in new compact packaging concept.  相似文献   
3.
Integrated model-driven dashboard development   总被引:1,自引:0,他引:1  
Business performance modeling and model-driven business transformation are two research directions that are attracting much attention lately. In this study, we propose an approach for dashboard development that is model-driven and can be integrated with the business performance models. We adopt the business performance modeling framework, and we extend it in order to capture the reporting aspect of the business operation. We describe models that can effectively represent all the elements necessary for the business performance reporting process, and the interactions among them. We demonstrate how all these models can be combined and automatically generate the final solution. We further extend the proposed framework with mechanisms that can detect changes in the models and incrementally update the deployed solutions. Finally, we discuss our experience from the application of our technique in a real-world scenario. This case study shows that our technique can be efficiently applied to and handle changes in the underlying business models, delivering significant benefits in terms of both development time and flexibility.  相似文献   
4.
Niobium nitride superconducting films have been deposited by reactive rf magnetron sputtering. Polyepitaxial growth on MgO-coated substrates greatly improves the superconducting properties. The overall film resistivity is found to be widely dependent on the total pressure of the gas mixture. Samples with a negative temperature coefficient of resistance exhibit 3D weak localization effects as characterized by magnetoresistance measurements. The inelastic scattering time is found to vary as T–p with p2, in the temperature range Tc-3Tc.Laboratoire associé au C.N.R.S.  相似文献   
5.
6.
The diastereoselective hydrogenation catalyzed by heterogeneous metallic catalysts uses a covalently bound chiral auxiliary to induce the chirality. It remains an active synthetic methodology in the asymmetric synthesis of chiral products and may proceed with high diastereoselectivity. This review describes recent examples using this method, such as hydrogenation of C=C, C=O, and C=N bonds. The use of a chiral auxiliary group has also been successfully applied to the hydrogenation of aromatic and heteroaromatic rings. The choice of the chiral auxiliary was found to play a key role in the asymmetric hydrogenation. The results could be explained in terms of steric effect, with a preferred conformation of the adduct substrate and the addition occurring from the less bulky side. The catalytic metal, the support and the presence of additives were also found to have a significant influence.  相似文献   
7.
Regional planning has long sought to manage places that extend across political boundaries. The international trend to decentralize governance and promote co-management of protected areas is consistent with emerging collaborative spatial planning theory (Healey, 1997, 1999, 2006), which suggests that through dialogue, parties assert multiple cultural perspectives, share knowledge, and forge shared landscape values as the basis of decisions. As a form of collaborative spatial planning, co-management specifies shared resource management power between national government and one or more local or indigenous communities. Both approaches assume decentralized governance systems. Although critics fault collaborative planning for glossing over historical and cultural contexts, and for ignoring power in decision making, few case studies ask why partners participate or how specific decentralized governance institutions affect plan implementation. This paper draws from a study of co-management at Mount Pulag National Park, the Philippines—a shared indigenous cultural landscape that was to be managed by a board representing multiple local, indigenous, and national jurisdictions. Tracing road decisions by two municipal partners, the paper summarizes how and why major stakeholders adopted and then circumvented protective policies by building duplicative road projects across fragile forests. In this context of changing indigenous rights, the same decentralization laws that enabled co-management also rewarded competition and strategic behavior that weakened the collaborative and fragmented the shared landscape. The case demonstrates the need to interrogate, rather than assume the benefits of decentralized governance and to study why stakeholders participate before relying on voluntary collaboration to manage regional landscapes. The initial version of this paper was presented to the 2006 annual meetings of the Association of Collegiate Schools of Planning, Fort Worth, Texas.  相似文献   
8.
The heterocoupling between 2-nitrobenzoic and 2,6-dimethoxybenzoic acids was studied. It was demonstrated that the [PdCl2/Cu(OH)2:0.2/0.75 equiv.] catalytic system can catalyze this reaction with significant yield. Further optimizations (i.e.: sources and loadings of copper and palladium salts, base) allowed to isolate the biaryl in 70 % yield. A catalytic cycle that accounts for the observed results is proposed. While the bi-metal catalyst has shown high yields with some substrates, it is only able to catalyze the decarboxylative coupling in high yield for some of the substrates studied.  相似文献   
9.
Three groups of amygdala-kindled rats received 10 bidaily treatment trials: On each trial, the drug-before group received a diazepam (2.5 mg/kg i.p.) injection 1 hr before a convulsive stimulation, the drug-after group received a diazepam injection 1 hr after a stimulation, and the vehicle control group received a vehicle injection either 1 hr before or 1 hr after a stimulation. After treatment, only the drug-before group displayed significantly longer forelimb clonus under the influence of diazepam (that is, they displayed contingent tolerance to diazepam's anticonvulsant effect) and significantly longer forelimb clonus while drug free. Following a 14-day retention period, the rats in the drug-before group retained significant levels of contingent tolerance but did not display significant increases when tested drug free. These data suggest that compensatory responses do not play a causal role in the expression of contingent tolerance.  相似文献   
10.
Took telemetric recordings of a male 23-yr-old chronic schizophrenic patient's heart rate and skin potential while on the ward. During periods of hallucinations, the skin potential increased significantly, while there were no changes in heart rate. Neither heart rate nor skin potential increased during periods of talking. When very angry, heart rate showed a substantial deceleration followed by a large increase. There was no change in skin potential during the period of anger. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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