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1.
This paper describes a newly developed logic circuit family based on dual-rail bit lines and sense amplifiers that is used extensively in a 1.0-GHz, single-issue, 64-bit PowerPC integer processor, gigahertz unit test site (guTS). The family consists of an incrementor, a count-leading-zero, a rotator, and a read-only memory. Each macro consists of a leaf-cell array, dual-rail bit lines, a row of sense amplifiers, a control block, and peripheral circuits. A common read-out scheme sensing the differential voltage of dual-rail bit lines is used. The hardware was fabricated in a 0.25-μm drawn channel length, six-metal-layer (Al) CMOS technology (1.8-V nominal VDD). Wafer testing was performed using a probe card. The macros were tested cycle by cycle by scanning the input data to the read/write address latches and data latches, and scanning the result out from the output receiving latches. Functional testing was performed on guTS macros at frequencies up to 1.0 GHz at 25°C with nominal VDD (1.1 GHz for the ROM)  相似文献   
2.
Virtual-reality heritage presentation at Ename   总被引:1,自引:0,他引:1  
Virtual reality (VR) and multimedia are central components of the heritage presentation programme at Ename, Belgium. These techniques are designed to help the visitor understand and experience the past as revealed through archaeological and historical research. The programme uses different VR approaches to bring to life archaeological remains, standing monuments and elements of the historical landscape for visitors. We named the overall project “Ename 974” to commemorate the foundation date of the first mediaeval settlement. Its major aim is to communicate new insights about archaeology, history and conservation to the general public, paying great attention to scholarly accuracy and by means of multimedia technologies. Among the most important of these technologies are on-site virtual reconstructions, museum multimedia and educational projects. Since 1998, the Ename Centre for Public Archaeology and Heritage Presentation has served as an international extension of the Ename 974 project. Its goal is to develop new technologies and new standards for heritage presentation. It also coordinates heritage presentation projects and educational programmes for partner sites around the world  相似文献   
3.
Natural nucleotides are not useful as fluorescent probes because of their low quantum yields. Therefore, a common methodology for the detection of RNA and DNA is the application of extrinsic fluorescent dyes coupled to bases in oligonucleotides. To overcome the many limitations from which fluorescent nucleotide-dye conjugates suffer, we have developed novel purine nucleosides with intrinsic fluorescence to be incorporated into oligonucleotide probes. For this purpose we synthesized adenosine and guanosine fluorescent analogues 7-25, conjugated at the C8 position with aryl/heteroaryl moieties either directly, or via alkenyl/alkynyl linkers. Directly conjugated analogues 7-14, exhibited high quantum yields, φ >0.1, and short λ(em) (<385 nm). Alkynyl conjugated analogues 22-25, exhibited low quantum yields, φ <0.075, and λ(em)<385 nm. The alkenyl conjugated analogues 15-21, exhibited λ(em) 408-459 nm. While analogues 15,16, and 20 bearing an EDG on the aryl moiety, exhibited φ <0.02, analogues 17, and 21 with EWG on the aryl moiety, exhibited extremely high quantum yields, φ ≈ 0.8, suggesting better intramolecular charge transfer. We determined the conformation of selected adenosine analogues. Directly conjugated analogue 8 and alkynyl conjugated analogue 22, adapted the syn conformation, whereas alkenyl conjugated analogue 15 adapted the anti conformation. Based on the long emission wavelengths, high quantum yields, anti conformation and base-paring compatibility, we suggest analogues 17 and 21 for further development as fluorescent probes for the sensitive detection of genetic material.  相似文献   
4.
The effect of pigments of different chemical compositions on the crystellization process of PP was studied by means of differential scanning calorimetry in isothermal mode. The Avrami equation was applied to obtain the crystallization parameters of polypropylene with different pigments. Lipatov's equations were applied for evaluation of the thickness and volume content of the transition layers. Results show that pigments affect not only the degree of crystallinity but also the structure of the amorphous phase and the integrity of the crystalline/amorphous interphase. Finally, the morphology and mechanical properties of pigmented polypropylene were studied in view of the different chemical compositions of the various pigments.  相似文献   
5.
Annealed (H1) and cold-rolled (H2) HAVAR has been studied using high-pressure synchrotron X-ray diffraction. A structural phase transformation was discovered at ~13 GPa at ambient temperature, transforming from m ??3 m (S.G. 225) to P 63/m m c (S.G. 194) symmetry. The transition was not reversible on pressure release. The low-pressure cubic phase was found to be more compressible than the high-pressure hexagonal phase. Conventional Mössbauer and NFS shows that the HAVAR is not magnetic at room temperature and no splitting is observed. The SQUID indicates a huge difference in the temperature dependence of the magnetic susceptibility between the cold Rolled HAVAR compared to the annealed HAVAR.  相似文献   
6.
The alternant molecular orbital (AMO) method was applied to the ground state of naphthalene. Both the single and the many-parameter variants lead to substantial improvement in the energy. Comparison with a limited configurational interaction treatment shows that the AMO method is better in the many-parameter variant.
Zusammenfassung Die Methode der alternierenden MO (AMO) wurde auf den Grundzustand des Naphthalins angewandt. Beide Varianten der Methode, mit einem sowie mit mehreren Parametern, bringen wesentliche Verbesserung in der Energie. Vergleich mit einer beschrÄnkten Konfigurations-Wechselwirkungs-Methode zeigt, da\ die AMO-Methode besser ist, wenn mehrere Parameter angewandt werden.

Résumé La méthode des orbitales moléculaires alternantes (AMO) est appliquée a l'état-fondamental du naphthalène. Les variantes a un ou plusieurs parametres de cette methode produisent des améliorations substantielles pour l'énergie. La comparison avec une application de la méthode d'interaction de configurations limitée montre que la méthode AMO est plus efficace dans la variante avec plusieurs parametres.
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8.
The organization and circuit design of a 1.0 GHz integer processor built in 0.25 μm CMOS technology are presented, a microarchitecture emphasizing parallel computation with a single late select per cycle, structured control logic implemented by read-only-memories and programmable logic arrays, and a delayed reset dynamic circuit style enabling complex functions to be implemented in a few levels of logic are among the key design choices described. A means for at-speed scan testing of this high-frequency processor by a low-speed tester is also presented  相似文献   
9.
We prove lower bounds for the entropy of limit measures associated to non-degenerate sequences of eigenfunctions on locally symmetric spaces of non-positive curvature. In the case of certain compact quotients of the space of positive definite n × n matrices (any quotient for n = 3, quotients associated to inner forms in general), measure classification results then show that the limit measures must have a Haar component. This is consistent with the conjecture that the limit measures are absolutely continuous.  相似文献   
10.
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