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1.
Meetings are an important form of interaction in business settings. However, meetings are often not held in a way that makes all participants feel engaged. Meeting support systems try to overcome this obstacle by helping meeting participants in the meeting workflow. This paper takes a complementary approach by distinguishing between different perspectives of good meetings: the peopleware perspective, the generic groupware perspective, and the roomware perspective. It is argued that all these perspectives have to be considered simultaneously when heading toward an ideal meeting system design. The paper presents excerpts of a pattern language that empowers users to improve their meeting. Besides this, the pattern language can be considered as a tool for the designer. After showing, how both groups made use of the patterns, the paper finally presents LivingAgendas, a meeting support system that can accompany the meeting participant through the meeting life cycle.  相似文献   
2.
Complex eScience and other sophisticated applications in the field of HPC imply new demands that queuing based resource management systems cannot meet. To guarantee Quality of Service and co-allocation in the Grid, planning based resource management systems implementing advance reservation are needed. These systems face new challenges as a planning based management system has to keep track of the jobs and reservations in the future. Additionally, during the negotiation process of incoming reservations, a good overview of the remaining, not-yet reserved capacity is needed—not only for the current allocation, but also for the whole book-ahead time. Therefore, the resource management problem becomes a two dimensional problem for advance reservations in this field. In this paper different data structures are investigated and discussed in order to fit to planning based resource management. As a result the benefits of using lists of resource allocation or free blocks are exposed. This general idea widely used to manage continuous resources is extended to cover not only the resource dimension but also the time dimension. The list of blocks approach is evaluated in a Grid level and a local resource management system for a computing cluster. The extensive simulations showed a better runtime and higher reservation success rate compared with the currently favored approach of a slotted time and the more sophisticated approach based on AVL trees.  相似文献   
3.
We explore the impact of edge states in three types of transition metal dichalcogenides (TMDs), namely metallic Td-phase WTe2 and semiconducting 2H-phase MoTe2 and MoS2, by patterning thin flakes into ribbons with varying channel widths. No obvious charge depletion at the edges is observed for any of these three materials, in contrast to observations made for graphene nanoribbon devices. The semiconducting ribbons are characterized in a three-terminal field-effect transistor (FET) geometry. In addition, two ribbon array designs have been carefully investigated and found to exhibit current levels higher than those observed for conventional one-channel devices. Our results suggest that device structures incorporating a high number of edges can improve the performance of TMD FETs. This improvement is attributed to a higher local electric field, resulting from the edges, increasing the effective number of charge carriers, and the absence of any detrimental edge-related scattering.
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4.
磁悬浮无轴承电动机发展、应用和前景   总被引:3,自引:0,他引:3  
综述了磁悬浮无轴承电动机起源及发展历史,介绍了磁悬浮无轴承电动机的基本原理,详细论述了磁悬浮无轴承电动机在半导体工业、化工工业及生物工程等领域的应用特点和意义,展望了我国研究和应用磁悬浮无轴承电动机前景。  相似文献   
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High‐temperature time‐of‐flight neutron diffraction experiments were performed on cubic yttria‐stabilized zirconia (YSZ, 10 mol% YO1.5) and lanthanum zirconate (LZ) prepared by laser melting. Three spheroids of each composition were aerodynamically levitated and rotated in argon flow and heated with a CO2 laser. Unit cell, positional and atomic displacement parameters were obtained by Rietveld analysis. Below ~1650°C the mean thermal expansion coefficient (TEC) for YSZ is higher than for LZ (13 ± 1 vs. 10.3 ± 0.6) × 10?6/K. From ~1650°C to the onset of melting of LZ at ~2250°C, TEC for YSZ and LZ are similar and within (7 ± 2) × 10?6/K. LZ retains the pyrochlore structure up to the melting temperature with Zr coordination becoming closer to perfectly octahedral. Congruently melting LZ is La deficient. The occurrence of thermal disordering of oxygen sublattice (Bredig transition) in defect fluorite structure was deduced from the rise in YSZ TEC to ~25 × 10?6/K at 2350°C–2550°C with oxygen displacement parameters (Uiso) reaching 0.1 Å2, similar to behavior observed in UO2. Acquisition of powder‐like high‐temperature neutron diffraction data from solid‐levitated samples is feasible and possible improvements are outlined. This methodology should be applicable to a wide range of materials for high‐temperature applications.  相似文献   
7.
Bioprinting can be defined as the art of combining materials and cells to fabricate designed, hierarchical 3D hybrid constructs. Suitable materials, so called bioinks, have to comply with challenging rheological processing demands and rapidly form a stable hydrogel postprinting in a cytocompatible manner. Gelatin is often adopted for this purpose, usually modified with (meth‐)acryloyl functionalities for postfabrication curing by free radical photopolymerization, resulting in a hydrogel that is cross‐linked via nondegradable polymer chains of uncontrolled length. The application of allylated gelatin (GelAGE) as a thiol–ene clickable bioink for distinct biofabrication applications is reported. Curing of this system occurs via dimerization and yields a network with flexible properties that offer a wider biofabrication window than (meth‐)acryloyl chemistry, and without additional nondegradable components. An in‐depth analysis of GelAGE synthesis is conducted, and standard UV‐initiation is further compared with a recently described visible‐light‐initiator system for GelAGE hydrogel formation. It is demonstrated that GelAGE may serve as a platform bioink for several biofabrication technologies by fabricating constructs with high shape fidelity via lithography‐based (digital light processing) 3D printing and extrusion‐based 3D bioprinting, the latter supporting long‐term viability postprinting of encapsulated chondrocytes.  相似文献   
8.
By using the D(d, p)3H nuclear reaction combined with the Rutherford-backscattering method, the amount of D2O in relation to H2O in water from the Dead Sea is measured. The amount of deuterium in the samples is determined from the integrated yield of the D(d, p)3H reaction in relation to the 16O(d, p0)17O or 16O(d, p1)17O reaction. For the low deuteron energies used (E 0.63 MeV), the differential cross section of the 16O(d, p0)17O reaction was determined experimentally. No significant change of deuterium concentration in Dead-Sea water down to a depth of 36 m could be detected.  相似文献   
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