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81.
Eberhard HÄnsler 《电信纪事》1994,49(7-8):360-367
Providing means for a full-duplex hands-free telephone conversation is still a research topic in many communication and signal processing laboratories around the world. More than ninety publications mainly from the last two and a half years support this statement. The reason for these activities lies in the complexity of the problem: full-duplex telephone communication without hand-sets requires electronic replicas of the loudspeaker-enclosure-microphone systems used by the communicating parties. The impulse response of such a system is typically several 100 ms long and time varying. Therefore, the replica has to be adaptive while the adaptation is controlled by speech signals. Regarding these requirements the hands-free telephone problem may currently be considered as one of the most challenging signal processing problems. This bibliography supplements a bibliography composed approximately two and a half years ago [29]. Brief summaries are given on papers published since then. 相似文献
82.
Utsey Shawn O.; Giesbrecht Norman; Hook Joshua; Stanard Pia M. 《Canadian Metallurgical Quarterly》2008,55(1):49
This study tested a sociocultural model of stress and coping in a sample of 215 African Americans. Psychological resources (optimism, ego resilience) were modeled as a "nested self" (S. E. Hobfoll, 2001), supported by social resources (family adaptability and cohesion) and cultural resources (racial pride, religiosity). Race-related stress was a significantly more powerful risk factor than stressful life events for psychological distress. Structural equation modeling results confirmed the hypotheses that psychological resources had a significant direct effect in minimizing psychological distress, and social resources had a significant stress-suppressing effect on race-related stress. Theoretical and practical implications for counseling psychologists are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
83.
The objective of this paper is to identify and analyse factors that are important for winning acceptance of wind-energy parks on the local level. The developers of wind-energy parks need to know how to manage “social acceptance” at the different stages of planning, realisation and operation. Five case studies in France and Germany focused on factors of success in developing a wind-energy project on a given site and illuminated how policy frameworks influence local acceptance. Our hypothesis is that these factors fall into two categories: institutional conditions, such as economic incentives and regulations; and site-specific conditions (territorial factors), such as the local economy, the local geography, local actors, and the actual on-site planning process (project management). 相似文献
84.
85.
Pentti JÄrvelÄ Juha Sarlin Pirkko JÄrvelÄ Pertti TörmÄlÄ 《Journal of Materials Science》1986,21(9):3139-3142
Cellular polystyrene (EPS) is the most commonly used cellular thermoplast whose main applications are insulation and packages.
One of its new applications is core material in building elements, and this poses higher requirements for strength. This is
particularly evident in self-supporting roof elements. This study presents a method for determining the fusion strength between
beads in cellular polystyrene and the dependence of this strength on processing. This method has also enabled us to determine
the adhesion of cellular polystyrene beads to other materials, such as glass fibre, and it allows measurement of the fusion
strength between EPS beads without the influence of porosity. Fusion strength was found to have a characteristic behaviour.
It has an absolute upper limit, and fusion forces approximate this limit asymptotically as heating time is prolonged (this
increase is dependent on the energy content of the steam). 相似文献
86.
87.
Behaviour of systems is described by formal languages: the sets of all sequences of actions. Regarding abstraction, alphabetic language homomorphisms are used to compute abstract behaviours. To avoid loss of important information when moving to the abstract level, abstracting homomorphisms have to satisfy a certain property called simplicity on the concrete (i.e. not abstracted) behaviour. To be suitable for verification of so called co-operating systems, a modified type of satisfaction relation for system properties (approximate satisfaction) is considered. The well known state space explosion problem is tackled by a compositional method formalized by so called co-operation products of formal languages. 相似文献
88.
Gian Mario Bragallini Maria Pia Cavatorta Philippe Sainsot 《Tribology International》2003,36(12):935-941
A strain approach for the design of coated contacts is described, allowing a simple evaluation of the risk of coating failure, once the elastic modulus of the coating and the substrate and the coating thickness are known. Examples are provided for hard and soft coatings. The approach is shown to be particularly useful for hard coatings, where failure is mainly related to tensile longitudinal stresses at the interface. Results from the proposed strain approach compare well with data from a standard stress analysis. Finally, the level of approximation introduced by evaluating the strain field for the reference Hertzian case is discussed, showing that the error introduced is not acceptable. 相似文献
89.
Iikka ISOMÄKI Rui ZHANG Long-gong XIA Niko HELLSTEN Pekka A. TASKINEN 《中国有色金属学会会刊》2018,28(9):1869-1877
ZnO-containing slags are common in pyrometallurgical processing of the base metals and steel. This caused the interest to the thermodynamics of the ZnO-SiO2 system. A complete literature survey, critical evaluation of the available experimental data and a thermodynamic optimization of the phase equilibria and thermodynamic properties of the system ZnO-SiO2 at 1.013×105 Pa are presented. The molten oxide was described as an associate solution. The properties of liquid were reassessed and enthalpy term of the Gibbs energy of solid Zn2SiO4 was re-fitted to be compatible with the new data in the willemite primary phase field. The thermodynamic data set agrees well with the recent experimental observations. It can be used for predicting, e.g., the thermodynamic properties and the domains of the phase diagram, like critical point of the liquid miscibility gap, with a better accuracy than using the previous assessments. A set of optimized model parameters were obtained, reproducing the reliable thermodynamic and phase equilibrium data within their experimental errors from 298 K to liquidus temperatures, over the entire composition range. The created database can be used in a Gibbs energy minimization software to calculate the thermodynamic properties and the phase diagram sections of interest. 相似文献
90.
Anna Li Santi Filomena Napolitano Nunzia Montuori Pia Ragno 《International journal of molecular sciences》2021,22(8)
Proteolysis is a key event in several biological processes; proteolysis must be tightly controlled because its improper activation leads to dramatic consequences. Deregulation of proteolytic activity characterizes many pathological conditions, including cancer. The plasminogen activation (PA) system plays a key role in cancer; it includes the serine-protease urokinase-type plasminogen activator (uPA). uPA binds to a specific cellular receptor (uPAR), which concentrates proteolytic activity at the cell surface, thus supporting cell migration. However, a large body of evidence clearly showed uPAR involvement in the biology of cancer cell independently of the proteolytic activity of its ligand. In this review we will first describe this multifunctional molecule and then we will discuss how uPAR can sustain most of cancer hallmarks, which represent the biological capabilities acquired during the multistep cancer development. Finally, we will illustrate the main data available in the literature on uPAR as a cancer biomarker and a molecular target in anti-cancer therapy. 相似文献