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11.
Electric vehicles (EVs) have a limited driving range compared to conventional vehicles. Accurate estimation of EV's range is therefore a significant need to eliminate “range anxiety” that refers to drivers' fear of running out of energy while driving. However, the range estimators used in the currently available EVs are not sufficiently accurate. To overcome this issue, more accurate range estimation techniques are investigated. Nonetheless, an accurate power‐based EV energy consumption model is crucial to obtain a precise range estimation. This paper describes a study on EV energy consumption modelling. For this purpose, EV modelling is carried out using MATLAB/Simulink software based on a real EV in the market, the BMW i3. The EV model includes vehicle powertrain system and longitudinal vehicle dynamics. The powertrain is modelled using efficiency maps of the electric motor and the power electronics' data available for BMW i3. It also includes a transmission and a battery model (ie, Thevenin equivalent circuit model). A driver model is developed as well to control the vehicle's speed and to represent human driver's behaviour. In addition, a regenerative braking strategy, based on a series brake system, is developed to model the behaviour of a real braking controller. Auxiliary devices are also included in the EV model to improve energy consumption estimation accuracy as they can have a significant impact on that. The vehicle model is validated against published energy consumption values that demonstrates a satisfactory level of accuracy with 2% to 6% error between simulation and experimental results for Environmental Protection Agency and NEDC tests. 相似文献
12.
Velayati Mahin Sabouri Zahra Masoudi Abdolhossein Mostafapour Asma Khatami Mehrdad Darroudi Majid 《SILICON》2022,14(13):7541-7554
Silicon - In this research, epoxy polyurethane-nano silica nanocomposites have been synthesized using an in-situ method, for which SiO2 nanocomposites had been initially ready in N,... 相似文献
13.
Farid Jamali-Sheini Ramin Yousefi M.R. Mahmoudian Nabeel Ali Bakr Abdolhossein Sa΄aedi Nay Ming Huang 《Ceramics International》2014
Te-doped ZnO nanostructures were synthesized by an annealing (vapor–solid) process under ambient conditions, and characterized in terms of their morphological, structural, compositional and optical properties. The structural and morphological characterizations revealed that the synthesized nanostructures were well-defined multipods, needles and spherical particles, and possessed well-crystalline ZnO wurtzite hexagonal phase. Also, in the X-ray diffraction studies, the presence of a shift in the peak positions towards a lower angle, and a decrease in the intensity, with an increase in the Te concentration, as compared to the undoped ZnO, were observed. The chemical composition confirmed the presence of Te, in the case of multipod and needle morphologies. The effect of doping on the crystalline quality and optical properties was also investigated, by using photoluminescence (PL) and Raman spectrometers. The Raman results demonstrated that the doped ZnO nanostructures had a lower crystalline quality than the undoped ZnO. Moreover, the PL results showed a decrease in the band gap for the doped ZnO nanostructures, in comparison to the undoped ZnO. A possible growth mechanism was also proposed. 相似文献
14.
15.
A. Abdel‐Hafez A. Miri L. Orozco‐Barbosa 《International Journal of Network Management》2006,16(3):185-202
With the widespread use of the Internet, the popularity of group communication‐based applications has grown considerably. Since most communications over the Internet involve the traversal of insecure networks, basic security services are necessary for these collaborative applications. These security services can be facilitated if the authorized group members share a common secret. In such distributed applications, key agreement protocols are preferred to key distribution protocols. In the past two decades, there have been many proposals for key agreement protocols. Most of these protocols are not efficient and limit the size of the underlying group. In this paper, we consider the scalability problem in group key agreement protocols. We propose a novel framework based on extension of the Diffie–Hellman key exchange protocol. The efficiency of our protocol comes from the clustering of the group members, where the common session key is established collaboratively by all participants. We present the auxiliary protocols needed when the membership changes. We show that our protocol is superior in complexity in both communication and computation overheads required to generate the session key. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
16.
Transition from traditional to ICT-enhanced learning environments in undergraduate chemistry courses
This paper describes a three-year study conducted among chemistry instructors (professors and teaching assistants) at a post-secondary institution. The goal was to explore the integration process of information and communication technologies (ICT) into traditional teaching. Four undergraduate chemistry courses incorporated a course website, an electronic forum, computerized visualizations, and Web-based projects, into their curriculum. The learning technologies were integrated to enhance inquiry-based learning, visualizations, and knowledge sharing. The current study investigated chemistry instructors’ perceptions toward ICT and their activities while practicing the newly introduced technologies. The findings showed that integrating new practices is a phase-dependent process that consists of promises as well as complexities. Four transition steps were found to characterize the integration of ICT-learning environments: non-active, support-dependant, partial-independant, and total-independant. Findings indicated that the transition from traditional to ICT-enhanced learning environments involves ambivalent feelings and dichotomy among instructors. 相似文献
17.
Reviews the book, The dissociative mind by Elizabeth F. Howell (see record 2005-14945-000). In her book, The Dissociative Mind, Elizabeth Howell presents a complex and thorough overview of what she describes as a "sea change" in psychoanalytic theory. From her vantage point as both psychoanalyst and traumatologist, she demonstrates how, in the last 15-20 years, relational trauma and the resulting impact on the individual mind-namely the splits and fissures that comprise dissociation- have made their way back into psychoanalytic thinking. Howell's elaboration of the overwhelmed, traumatized mind is very useful in clients who present with problems in thinking or who have limited capacity to symbolize. However, detailed clinical material of how an analyst thinking of dissociated self states would work with such a client, what Bromberg termed the "relational bridge," would support her fundamental assertions more effectively. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
18.
Objective: To investigate the relations among wives' labeling of their husbands' psychiatric disorder or brain injury as an organic illness, the husbands' perceived control over their disabilities, and the husbands' mental health. Participants: 57 male clients of the Department of Rehabilitation, Israel's Ministry of Defence (26 with a psychiatric disorder and 31 with a traumatic brain injury) and their wives. Measures: Illness Labeling Questionnaire, the Perceived Control Over Illness Questionnaire, and the Mental Health Inventory. Results: Husbands' mental health was low but did not differ according to disability; wives' labeling of husbands' condition was negatively related to the husbands' mental health; husbands' perceived control was positively related to their mental health for both disabilities. Conclusion: Organic illness labels, even when adopted by the wives of the persons with the disability, seem to be negatively related to that person's mental health, whereas perceived control over a mental disorder or a brain injury seems to contribute positively to mental health, independently of how the disorder or injury is labeled. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
19.
Rapid distribution of newly released confidential information is often impeded by network traffic jams, especially when the
confidential information is either crucial or highly prized. This is the case for stock market values, blind auction bidding
amounts, many large corporations'strategic business plans, certain news agencies'timed publications, and some licensed software
updates. Hierarchical time-based information release (HTIR) schemes enable the gradual distribution of encrypted confidential
information to large, distributed, (potentially) hierarchically structured user communities, and the subsequent publication
of corresponding short decryption keys, at a predetermined time, so that users can rapidly access the confidential information.
This paper presents and analyzes the efficiency of a novel HTIR scheme.
Deholo Nali holds a M.Sc. in mathematics and a Ph.D. in Computer Science from the University of Ottawa, Canada. In the past, he worked
for two years as a software developer and pursued research in the design and analysis of identity-based cryptographic protocols.
His research interests now include identity theft and graphical password authentication. 相似文献
20.
Azadeh A. Hosseini N. Abdolhossein Zadeh S. Jalalvand F. 《The International Journal of Advanced Manufacturing Technology》2015,81(1-4):135-148
The International Journal of Advanced Manufacturing Technology - Unstable environment of industrial systems is a source of various uncertainties in production features such as processing times.... 相似文献