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21.
Sharon?Olivera Handanahally?Basavarajaiah?MuralidharaEmail author Krishna?Venkatesh Keshavanarayana?Gopalakrishna Chinnaganahalli?Suryaprakash?Vivek 《Journal of Materials Science》2016,51(8):3657-3674
ABS is an engineering plastic that has butadiene part uniformly distributed over the acrylonitrile-styrene matrix. It possesses excellent toughness, good dimensional stability, easy processing ability, chemical resistance, and cheapness. However, it suffers from inherent shortcomings in terms of mechanical strength and vulnerability to environmental conditions. Furthermore, it is non-conducting and easily fretted. Plating on ABS can serve to enhance the strength and structural integrity as well as to improve durability and thermal resistance resulting in metallic properties on the ABS material. ABS is described as the most suitable candidate for plating because it is possible to deposit an adherent metal coating on it by only the use of chemical pretreatment process and without the use of any mechanical abrasion. This article aims to review the history of ABS plastics, properties of ABS, processes and mechanisms of plating, and studies of plating on ABS involving mainly eco-friendly methods of plating by discussing the literature published in recent years. The details of electroplating of ABS carried out in the authors’ laboratory are also presented. 相似文献
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Sharon Christensen William J. Caelli William D. Duncan 《Information & Communications Technology Law》2010,19(1):61-85
Critical, or national, information infrastructure protection, referred to as either CIIP or NIIP, has been highlighted as a critical factor in overall national security by the United States, the United Kingdom, India and the European Community. As nations move inexorably towards so-called ‘digital economies’, critical infrastructure depends on information systems to process, transfer, store and exchange information through the Internet. Electronic attacks such as denial of service attacks on critical information infrastructures challenge the law and raise concerns. A myriad of issues potentially plague the protection of critical information infrastructures owing to the lack of legal regulation aimed at ensuring the protection of critical information infrastructures. This paper will highlight the legal concerns that relate to the denial of service attacks on critical information infrastructures and provide an introductory overview of the law as it relates to CIIP in Australia. 相似文献
24.
Sharon Lee 《CAD/CAM与制造业信息化》2010,(2):70-73
设计研发最繁琐的工作,莫过于设计进行中及完成后所需递交的技术文件报告.为了解决这个棘手的问题,SolidWorks提供了3DVIA Composer文件发布系统,结合绘图者最想改善的速度问题,并加上支持3D同步变更的优势,大幅度降低了复杂3D的设计更新.可以整合图片、Office文件、PDF和HTML网页格式的各种规格,产生的编排布局规格变化,客户可由开放客制化的工具自行编排. 相似文献
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This study was an unobtrusive observational analysis of 333 older and younger bus passengers in Guadalajara, Mexico. A set of data were collected for each observed passenger, as well as more general observations related to driver behaviour, bus design and bus service characteristics. There were significant differences between older and younger passengers in terms of boarding and alighting times, use of handrails, seat location preferences, passenger stability and coping strategies in order to maintain postural stability. The conditions of travel are conducive to a poor passenger experience for the older passengers in particular. Although the problems may be attributed to bus design and driver behaviour typical of that in developing countries, they are also influenced by the wider transport infrastructure, and a lack of a regulatory regime which places drivers under time pressure and in direct competition with each other.
Practitioner Summary: Bus services must cater for all ages of passengers, including the elderly. This unobtrusive observational study investigated the passenger experience in a developing world city. Bus and wider service design were found to compromise the journey experience, with the older users being particularly negatively impacted. Design recommendations are provided. 相似文献
27.
Keefe DF Acevedo D Miles J Drury F Swartz SM Laidlaw DH 《IEEE transactions on visualization and computer graphics》2008,14(4):835-847
We present four studies investigating tools and methodologies for artist-scientist-technologist collaboration in designing multivariate, virtual reality (VR) visualizations. Design study 1 identifies the promise of 3D drawing-style interfaces for VR design and also establishes limitations of these tools with respect to precision and support for animation. Design study 2 explores animating artist-created visualization designs with scientific 3D fluid flow data. While results captured an accurate sense of flow that was advantageous as compared to the results of study 1, the potential for visual exploration using the design tools tested was limited. Design study 3 reveals the importance of a new 3D interface that overcomes the precision limitation found in study 1 while remaining accessible to artist collaborators. Drawing upon previous results, design study 4 engages collaborative teams in a design process that begins with traditional paper sketching and moves to animated, interactive, VR prototypes "sketched" by designers in VR using interactive 3D tools. Conclusions from these four studies identify important characteristics of effective artist-accessible VR visualization design tools and lead to a proposed formalized methodology for successful collaborative design that we expect to be useful in guiding future collaborations. We call this proposed methodology Scientific Sketching. 相似文献
28.
Sharon L. Kanfoush 《Lakes & Reservoirs: Research and Management》2013,18(2):99-113
Fourth Lake is a drainage lake at 43°N, 74°W, from which a 37‐cm long mud‐water interface core was recovered. 210Pb dating indicates the core spans ≈340 years, from the Little Ice Age through modern global warming. Diatom accumulation responds to anthropogenic watershed disturbances, declining slightly up‐core until a peak in the late‐1800s attributable to sediment and nutrient influx from logging and enlargement of the outlet dam. A dramatic decrease occurs ≈1900 as logging and lake filling ceased, and a smaller peak ≈1960 accompanies residential development. Similar changes occur in organic carbon accumulation, which ranges from 0.0038–0.024 mg cm?2 year?1, with generally decreasing values up‐core, punctuated by maximum values in the late‐1800s. Expressing diatoms as concentration, however, reveals a doubling up‐core that positively correlates with changes extending beyond the watershed, including Northern Hemisphere temperature, atmospheric CO2 concentration and solar irradiance (R = 0.627, 0.675 and 0.400, respectively). A >50% increase in % organic carbon, from 3.8% to 5.9%, also positively correlates with these larger‐scale environmental conditions (R = 0.828, 0.830 and 0.832), while negative correlations with the extrabasinal records are exhibited by magnetic susceptibility (R = ?0.654, ?0.496, and ?0.660) and clay (R = ?0.770, ?0.762, and ?0.737). These changes are consistent with decreased sediment influx and reduced dilution of biogenous sedimentary components. In contrast to total diatoms, the accumulation of planktonic genus Asterionella displays a long‐term increase up‐core. Potential explanations include increasing duration of the ice‐free season or a shift in the timing of the spring bloom and a mismatch with abundance of predator(s). Asterionella also increases as a percentage of total diatoms, being positively correlated with extrabasinal conditions (R = 0.827, 0.774 and 0.674). This change occurs at the expense of many benthic genera and, over the past century, at the expense of tychoplanktonic genus, Aulacosiera. Heavily silicified, Aulacosiera requires strong mixing to remain within the epilimnion. Thus, its decline might result from increasing stratification caused by warming. 相似文献
29.
D'Anna Kimberly L.; Stevenson Sharon A.; Gammie Stephen C. 《Canadian Metallurgical Quarterly》2005,119(4):1061
Lactating female mice fiercely defend offspring while exhibiting decreased fear and anxiety. Recent work (J. S. Lonstein & S. C. Gammie, 2002) found that intracerebroventricular (icv) injections of corticotropin releasing factor (CRF), a putative anxiogenic peptide, inhibit maternal defense behavior. This study examines effects of CRF-related peptides, urocortin (Ucn) 1 and Ucn 3, on maternal aggression in mice. Intracerebroventricular injections of both Ucn 1 (0.2 μg) and Ucn 3 (0.5 μg) reduced aggression but not pup retrieval. c-Fos levels were elevated by intracerebroventricular injections of Ucn 1 (0.2 μg) and Ucn 3 (0.5 μg) in 2 and 6 brain regions, respectively; however, both triggered increases in bed nucleus of the stria terminalis dorsal (BNSTd) and lateral septum (LS). These findings suggest that CRF-related peptides similarly modulate maternal aggression and that BNSTd/LS may be critical sites for negative regulation of maternal aggression. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
30.
Schwebel David C.; Brezausek Carl M.; Ramey Craig T.; Ramey Sharon L. 《Canadian Metallurgical Quarterly》2005,24(5):501
The number of immigrants in the United States is at an all time high, yet psychologists have largely ignored the domain of immigrant health. This article considers 1 aspect of immigrant health, risk for pediatric injury. A sample of over 5,000 5-year-old children from impoverished families was studied; approximately 13% had immigrant mothers. Children of immigrants had a significantly lower rate of injury in the prior year. This was particularly true of non-White children of immigrants. Three possible mediators for this finding--assistance with parenting, parenting style, and health care accessibility--were considered, but none explained the difference. The need for further research on the topic and implications of results for injury prevention are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献