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91.
Vehicular networking is considered a promising and enabling technology that helps in the realization and diversification of vehicle related applications such as road traffic safety, emergency management, and infotainment. For applications such as the road traffic safety, the system has to respond in certain bounded time and ensure higher reliability. A major bottleneck of the existing architectures is the reliability and scalability that results in a considerable performance degradation. Therefore, in this paper, we proposed a software defined peer to peer (P2P) architecture for reliable vehicular communications solution that scales out overall network intelligence into the system components (Road side units, on-board units, Gateways, Control centre) and offer an unprecedented reliability, adaptability and scalability. The reliability of the communication is achieved by using redundant system components such as multiple switches and GWs links that are deployed to achieve lower communication latencies and higher packet success rates. Furthermore, higher reliability is achieved by the application of fast-failover and fast recovery techniques. The proposed architecture is implemented using Docker, and containerized ONOS and Cassandra. The obtained results show that the proposed architecture offer higher reliability by offering higher packet success rate (PSR) and smaller round trip time (RTT). 相似文献
92.
赵涛 《河南机电高等专科学校学报》2001,9(2):58-60
新进期的高校思想政治工作,面临新的形势,产生新的问题,做好新形势下高校思想工作,必须明确分析情况,掌握新问题,探索和研究思想政治工作的基本规律,切实加强和改进思想政治工作。 相似文献
93.
94.
Abstract. In writings on the open source software development model, it is often argued that it is successful as a result of the gift economy that embraces activities in online communities. However, the theoretical foundations for this argument are seldom discussed and empirically tested. Starting with the 'classic' theories of gift giving, we discuss how they need to be developed in order to explain gift-giving practices in digital domains. In this paper, we argue that the gift economy is important, not only because it creates openness, but also because it organizes relationships between people in a certain way. Open source software development relies on gift giving as a way of getting new ideas and prototypes out into circulation. This also implies that the giver gets power from giving away. This power is used as a way of guaranteeing the quality of the code. We relate this practice to how gifts, in the form of new scientific knowledge, are given to the research community, and how this is done through peer review processes. 相似文献
95.
Walden Brent; McGue Matt; lacono William G.; Burt S. Alexandra; Elkins Irene 《Canadian Metallurgical Quarterly》2004,113(3):440
Although behavior genetic studies have suggested that early substance use is primarily environmentally mediated, no study has sought to identify the specific sources of environmental variance. Using data obtained from multiple informants, this study assessed the contributions of peer deviance and parent-child relationship problems to substance use in 14-year-old male and female twins (N = 1,403) drawn from the Minnesota Twin Family Study (MTFS). All three phenotypes were influenced primarily by shared environmental variance (average c2 = .51), as was the overlap among them. Moreover, peer deviance and parent-child relationship problems accounted for approximately 77% of the variance in early substance use. Findings also indicated that peer deviance, but not parent-child relationship problems, accounted uniquely for variance in early substance use. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
96.
Ge Xiaojia; Brody Gene H.; Conger Rand D.; Simons Ronald L.; Murry Velma McBride 《Canadian Metallurgical Quarterly》2002,38(1):42
The effects of the pubertal transition on behavior problems and its interaction with family and neighborhood circumstances were examined with a sample of 867 African American children 10-12 years of age. Pubertal development status, pubertal timing, and primary caregivers' parenting behaviors were significantly related to affiliation with deviant peers and externalizing behaviors. Externalizing behavior among early-maturing children was associated positively with primary caregivers' use of harsh-inconsistent discipline and negatively with nurturant-involved parenting practices. Disadvantaged neighborhood conditions were significantly associated with deviant peer affiliation. The effect of pubertal transition varied according to family and neighborhood conditions: Early-maturing children living in disadvantaged neighborhoods were significantly more likely to affiliate with deviant peers. Early-maturing children with harsh and inconsistent parents were significantly more likely to have externalizing problems. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
97.
Snyder Rebecca J.; Zhang An J.; Zhang Zhi H.; Li Guang H.; Tian Yu Z.; Huang Xiang M.; Luo Lan; Bloomsmith Mollie A.; Forthman Debra L.; Maple Terry L. 《Canadian Metallurgical Quarterly》2003,117(3):235
Mother-reared (MR) and peer-reared (PR) captive giant panda (Ailuropoda melanoleuca) cubs were compared to evaluate the effects of early removal from mother on behavioral development. Males and females and twins and singletons were compared to assess the effects of social setting on behavioral development. Subjects included 2 PR females, 3 MR females, 3 MR males, and 3 mothers. MR cubs spent more time manipulating bamboo and fell more often than PR cubs. PR cubs spent more time inactive. Male cubs directed more playful behavior at their mothers. Twins spent more time play fighting with their mothers than with their siblings. The results suggest that peer-rearing does not provide young pandas with the same level of social stimulation as mother-rearing. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
98.
新开发大学城地区土地空间布局规划模式探析 总被引:9,自引:2,他引:7
提出针对大学城发展的“共享”(concept of sharing)与“拉动”(concept of encouragement)理念,通过对国内部分大学城的土地利 用布局研究,探讨新开发大学城周边地区的土地利用空间布局模式。 相似文献
99.
The effect of a new approach to group work on pupil-pupil and teacher-pupil interactions. 总被引:1,自引:0,他引:1
Blatchford Peter; Baines Ed; Rubie-Davies Christine; Bassett Paul; Chowne Anne 《Canadian Metallurgical Quarterly》2006,98(4):750
The main impetus for the SPRinG (social pedagogic research into grouping) project was to address the wide gap between the potential of group work and its limited use in schools. It is an ambitious project that developed key principles and strategies to improve the effectiveness of group work in everyday primary classes and across a whole school year. On-the-spot and video-based systematic observations showed more active, sustained engagement, more connectedness, and more higher order inferential joint reasoning within SPRinG groups than in control comparisons. The authors argue that group work can be successfully implemented into everyday school classrooms and improve pupil interactions, provided teachers take time to train pupils in the skills of group working. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
100.
Xianru Liu Shiguo Wang Hong Ji 《International Journal of Communication Systems》2014,27(12):3956-3970
In peer‐to‐peer (P2P) networks, with the aim to support semantic search and keep scalability at the same time, a novel double‐layer P2P protocol is proposed. Firstly, keywords representing resource characteristics are compressed into bloom filters and structured P2P layer is constructed. Secondly, through analyzing one's bloom filters, each node extracts its interest, which is represented by a characteristic vector V. After obtaining common interest among nodes through comparing their Vs, a small‐world model is constructed, and another unstructured P2P layer is obtained. Consequently, on the basis of the decentralized architecture, a double‐layer semantic search P2P protocol is structured. When objective resource is being located, its similarity to local interest is used to determine whether it should be located in unstructured P2P semantic layer or structured layer adaptively, which not only improves search efficiency but also supports semantic location more widely. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献