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101.
Giorgos Zacharia Theodoros Evgeniou Alexandros Moukas Petros Boufounos Pattie Maes 《Electronic Commerce Research》2001,1(1-2):85-100
We present a framework to study the microeconomic effects in a reputation brokered Agent mediated Knowledge Marketplace, when we introduce dynamic pricing algorithms. We study the market with computer simulations of multiagent interactions. In this marketplace, the seller reputations are updated in a collaborative fashion based on the performance of the user in the delegated tasks. To the best of our knowledge this is the first agent mediated marketplace where the agents use dynamic pricing based on dynamically updated reputations. The framework can be used to investigate the different equilibria reached, based on the level of intelligence of the selling agents, the level of price-importance elasticity of the buying agents, and the level of unemployment in the marketplace. Preliminary experiments addressing these issues are presented. 相似文献
102.
The Itanium processor cartridge is a packaging optimization for electrical and thermal performance in a server environment. The 3-in. x 5-in. cartridge contains the Itanium CPU, up to 4 megabytes of level-3 (L3) cache, an innovative power delivery scheme, and an integrated vapor chamber thermal spreading lid for removing power. Cartridges and a chip set can be ganged electrically by means of a glueless bidirectional, multidrop system bus. Power is delivered through a custom connection with separate voltages for the 0.18-micron CPU and 0.25-micron custom cache devices. An I2C serial connection provides access to system management features such as temperature monitoring and cartridge identification information 相似文献
103.
104.
The needs of the wireless and mobile user regarding information access and services are quite different than those of the desktop user. This need is not about browsing the Web but about receiving personalized services that are highly sensitive to the immediate environment and requirements of the user. Personalization appears to be the most appropriate solution to this need. It comes into aid by creating personalized portals that are specific for the wireless user, which (a) are focus on the local content and (b) directly tones down factors that break up the functionally of the Internet/wireless services when viewed through wireless devices; factors like the click count, user response time (the choice factor) and the size of the wireless network traffic. In this paper we present a flexible personalization system for the wireless user that takes into consideration user mobility, the local environment and the user and device profile. The system utilizes the various characteristics of mobile agents to support flexibility, scalability, modularity and user mobility. We present metrics appropriate to the wireless environment, and an initial performance evaluation indicating improvement ranging from 33% up to, for certain metrics, 60%. 相似文献
105.
Theodoros A. Papadopoulos Jens Meyer Hong Li Zelei Guan Antoine Kahn Jean‐Luc Brédas 《Advanced functional materials》2013,23(48):6091-6099
A combination of density functional theory and experimental measurements via ultraviolet and X‐ray photoelectron spectroscopies is used to explore the nature of the interface between the stoichiometric molybdenum trioxide (MoO3) or its under‐stoichiometric counterpart with oxygen vacancies, and an organic hole‐transport layer represented by 4,4′‐N,N′‐dicarbazole‐biphenyl (CBP). Upon adsorption of CBP, special attention is paid to i) the appearance of gap states and the reduction of the molybdenum oxide surface, and ii) the evolution of the work function. Very good agreement is found between theory and experiment. The near alignment of the CBP highest occupied molecular orbital with the Fermi level and the conduction band edge of molybdenum oxide points to facile hole collection or injection. 相似文献
106.
The step junction between a circular and an eccentric coaxial waveguide is analysed using a rigorous mode matching technique along with the Graff's addition theorem for cylindrical functions. The necessary expressions including the coupling integrals are considered analytically. Based on this analysis the off-centred coaxial iris in a circular waveguide is studied. Its properties are pointed out and the single and dual irises on the same diaphragm features are exploited for the design of bandpass filters. 相似文献
107.
E. Hatzikraniotis K. T. Zorbas I. Samaras Th. Kyratsi K. M. Paraskevopoulos 《Journal of Electronic Materials》2010,39(9):2112-2116
Thermoelectric generators (TEGs) make use of the Seebeck effect in semiconductors for the direct conversion of heat to electrical
energy. The possible use of a device consisting of numerous TEG modules for waste heat recovery from an internal combustion
(IC) engine could considerably help worldwide efforts towards energy saving. However, commercially available TEGs operate
at temperatures much lower than the actual operating temperature range in the exhaust pipe of an automobile, which could cause
structural failure of the thermoelectric elements. Furthermore, continuous thermal cycling could lead to reduced efficiency
and lifetime of the TEG. In this work we investigate the long-term performance and stability of a commercially available TEG
under temperature and power cycling. The module was subjected to sequential hot-side heating (at 200°C) and cooling for long
times (3000 h) in order to measure changes in the TEG’s performance. A reduction in Seebeck coefficient and an increase in
resistivity were observed. Alternating-current (AC) impedance measurements and scanning electron microscope (SEM) observations
were performed on the module, and results are presented and discussed. 相似文献
108.
Ioannis Neokosmidis Theodoros Rokkas Michael C. Parker Geza Koczian Stuart D. Walker Muhammad Shuaib Siddiqui Eduard Escalona 《Telematics and Informatics》2017,34(5):572-589
5G networks are rapidly becoming the means to accommodate the complex demands of vertical sectors. The European project CHARISMA is aiming to develop a hierarchical, distributed-intelligence 5G architecture, offering low latency, security, and open access as features intrinsic to its design. Finding its place in such a complex landscape consisting of heterogeneous technologies and devices, requires the designers of the CHARISMA and other similar 5G architectures, as well as other related market actors to take into account the multiple technical, economic and social aspects that will affect the deployment and the rate of adoption of 5G networks by the general public. In this paper, a roadmapping activity identifying the key technological and socio-economic issues is performed, so as to help ensure a smooth transition from the legacy to future 5G networks. Based on the fuzzy Analytical Hierarchy Process (AHP) method, a survey of pairwise comparisons has been conducted within the CHARISMA project by 5G technology and deployment experts, with several critical aspects identified and prioritized. The conclusions drawn are expected to be a valuable tool for decision and policy makers as well as for stakeholders. 相似文献
109.
Theodoros Damartzis Athanasios I. Papadopoulos Panos Seferlis 《Clean Technologies and Environmental Policy》2014,16(7):1363-1380
A generalized framework for the optimal design of post-combustion CO2 capture processes based on a systemic and flexible equilibrium separation model that employs orthogonal collocation on finite elements techniques is proposed. Within this context, a column section of adaptive separation capability and functionality serves as the fundamental structural block for the identification of efficient separation schemes. Separation column sections in combination with heat transfer blocks, as well as stream splitters and mixers enable the generation and evaluation of alternative flowsheet configurations within a nonlinear optimization program. The main objectives for the flowsheet evaluation involve separation and thermal efficiency that eventually impact the economics of the overall process. Vapor–liquid equilibrium calculations are performed using statistical associating fluid theory for potentials of variable range (Mac Dowell et al., Ind Eng Chem Res 49:1883–1899, 2010). The proposed design framework is used for the optimal design of five alternative flowsheet configurations for the separation of CO2 from a flue gas stream using a 30 % weight monoethanolamine aqueous solution. These flowsheets illustrate the various connection patterns between the process units and indicate suitable distribution of process-driving forces through which the overall efficiency can be drastically enhanced. 相似文献
110.
Stefan Weber Thomas Rath Jimmy Mangalam Birgit Kunert Anna Maria Coclite Martin Bauch Theodoros Dimopoulos Gregor Trimmel 《Journal of Materials Science: Materials in Electronics》2018,29(3):1847-1855
Perovskite solar cells with a planar p-i-n device structure offer easy processability at low temperatures, suitable for roll-to-roll fabrication on flexible substrates. Herein we investigate different hole transport layers (solution processed NiOx, sputtered NiOx, PEDOT:PSS) in planar p-i-n perovskite solar cells using the triple cation lead halide perovskite Cs0.08(MA0.17FA0.83)0.92Pb(I0.83Br0.17)3 as absorber layer. Overall, reproducible solar cell performances with power conversion efficiencies up to 12.8% were obtained using solution processed NiOx as hole transport layer in the devices. Compared to that, devices with PEDOT:PSS as hole transport layer yield efficiencies of approx. 8.4%. Further improvement of the fill factor was achieved by the use of an additional zinc oxide nanoparticle layer between the PC60BM film and the Ag electrode. 相似文献