Extensive Attention (extensive + attention)

Distribution by Scientific Domains


Selected Abstracts


Novel TRIP-Steel/Mg-PSZ Composite,Open Cell Foam Structures for Energy Absorption

ADVANCED ENGINEERING MATERIALS, Issue 3 2010
Christos G. Aneziris
Porous materials have received extensive attention for energy absorption in the last years. In terms of this study austenitic TRIP-steel/Mg-PSZ composite,open cell foam structures are formed based on replicas using open-celled polyurethane foam as a skeleton with and without a supporting dense face (jacket) coating. Their compression strength as well as their specific energy absorption SEA has been registered as a function of the compressive strain. The zirconia addition has reinforced the composite material with the face coating up to a compressive strain of 50%. The stress-induced martensitic transformation of partially stabilized zirconia phases has been investigated as a function of the compressive strain by EBSD. The zirconia phase transformation is triggered already at low compressive strains below 2%. [source]


Biomedical Applications of Layer-by-Layer Assembly: From Biomimetics to Tissue Engineering,

ADVANCED MATERIALS, Issue 24 2006
Z. Tang
Abstract The design of advanced, nanostructured materials at the molecular level is of tremendous interest for the scientific and engineering communities because of the broad application of these materials in the biomedical field. Among the available techniques, the layer-by-layer assembly method introduced by Decher and co-workers in 1992 has attracted extensive attention because it possesses extraordinary advantages for biomedical applications: ease of preparation, versatility, capability of incorporating high loadings of different types of biomolecules in the films, fine control over the materials' structure, and robustness of the products under ambient and physiological conditions. In this context, a systematic review of current research on biomedical applications of layer-by-layer assembly is presented. The structure and bioactivity of biomolecules in thin films fabricated by layer-by-layer assembly are introduced. The applications of layer-by-layer assembly in biomimetics, biosensors, drug delivery, protein and cell adhesion, mediation of cellular functions, and implantable materials are addressed. Future developments in the field of biomedical applications of layer-by-layer assembly are also discussed. [source]


"Quasi Track-One" Diplomacy: An Analysis of the Geneva Process in the Israeli,Palestinian Conflict,

INTERNATIONAL STUDIES PERSPECTIVES, Issue 2 2010
Amira Schiff
The diversity of unofficial diplomacy activities in the last three decades has led to extensive attention in theoretical literature to the role of unofficial diplomacy in conflict resolution processes and to the development of a broad range of concepts used to describe different types of unofficial diplomatic activities. Yet certain unofficial activities, such as the process that preceded the Geneva Accords, do not neatly conform to the prevailing unofficial diplomacy concepts. This study seeks to contribute to the theoretical development of the unofficial diplomacy theory through an examination of the assumptions underlying models and concepts relating to unofficial diplomacy as applied to the process leading to the drafting of the Geneva Accords. The study suggests that the unofficial diplomacy process leading to the Geneva Accords was in fact "a quasi track-one" diplomacy,a diplomacy characterized by unique features, some of which weakened its potential contribution to the policy-making process. [source]


Factors affecting the formation of fingering in water-assisted injection-molded thermoplastics

ADVANCES IN POLYMER TECHNOLOGY, Issue 2 2006
Shih-Jung Liu
Abstract Water-assisted injection-molding technology has received extensive attention in recent years, due to the lightweight of plastic parts, relatively low-resin cost per part, faster cycle time, and flexibility in the design and manufacture. However, there are still some unsolved problems that confound the overall success of this technology. One of these is the water "fingering" phenomenon, in which the water bubbles penetrate outside designed water channels and form finger-shape branches. This study has investigated the effects of various processing parameters on the formation of fingering in water-assisted injection-molded thermoplastic parts. Both amorphous and semicrystalline polymers were used to mold the parts. The influence of water channel geometry, including aspect ratio and fillet geometry, on the fingering was also investigated. It was found that water-assisted injection-molded amorphous materials gave less fingering, while molded semicrystalline parts gave more fingering when compared to those molded by gas-assisted injection molding. For the water channels used in this study, the channels with a rib on the top produced parts with the least water fingering. Water fingering in molded parts decreases with the height-to-thickness ratio of the channels. The water pressure, water injection delay time and short-shot size were found to be the principal parameters affecting the formation of water fingering. In addition, a numerical simulation based on the transient heat conduction model was also carried out to help better explain the mechanism for the formation of fingering in water-assisted injection-molded thermoplastics. © 2006 Wiley Periodicals, Inc. Adv Polym Techn 25: 98,108, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/adv.20062 [source]


Molecular systematics and population genetics of biological invasions: towards a better understanding of invasive species management

ANNALS OF APPLIED BIOLOGY, Issue 1 2009
J. Le Roux
Abstract The study of population genetics of invasive species offers opportunities to investigate rapid evolutionary processes at work, and while the ecology of biological invasions has enjoyed extensive attention in the past, the recentness of molecular techniques makes their application in invasion ecology a fairly new approach. Despite this, molecular biology has already proved powerful in inferring aspects not only relevant to the evolutionary biologist but also to those concerned with invasive species management. Here, we review the different molecular markers routinely used in such studies and their application(s) in addressing different questions in invasion ecology. We then review the current literature on molecular genetic studies aimed at improving management and the understanding of invasive species by resolving of taxonomic issues, elucidating geographical sources of invaders, detecting hybridisation and introgression, tracking dispersal and spread and assessing the importance of genetic diversity in invasion success. Finally, we make some suggestions for future research efforts in molecular ecology of biological invasions. [source]


A scheme for authentication and dynamic key exchange in wireless networks

BELL LABS TECHNICAL JOURNAL, Issue 2 2002
Uri Blumenthal
Despite significant shortcomings in the initial security architecture, 802.11 wireless LANs have experienced explosive growth in recent years. Ongoing work in IEEE standards bodies is currently attempting to fix these shortcomings. One specific topic that has received extensive attention is how to enable these networks to authenticate users and to dynamically establish per-user per-session cryptographic keys. The IEEE 802.1x Port-Based Access Control standard, which formalizes a new EAP-over-LAN (EAPOL) protocol, has emerged as the preferred way to achieve this. The EAPOL protocol employs the extensible authentication protocol (EAP), standardized by the Internet Engineering Task Force, to allow the use of existing and new authentication methods and authentication, authorization, and accounting (AAA) infrastructure. In this paper we present a new EAP scheme,called shared key exchange (SKE),suitable for use in 802.11 private or public access wireless LANs. The scheme relies on secure pre-shared secret keys in wireless LAN mobile nodes devices and AAA servers. When instantiated with relatively minor changes to RADIUS and EAP,the resulting protocol is provably secure and offers a full set of security features. A second, simplified protocol results from minimal modifications to existing RADIUS and EAP standards, but it provides a lower level of security. Both protocols efficiently support roaming scenarios wherein an end user roams across different networks and requires frequent re-authentication with low latency. The protocols can easily be extended to support migration to new AAA protocols such as DIAMETER. © 2002 Lucent Technologies Inc. [source]