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排序方式: 共有615条查询结果,搜索用时 31 毫秒
31.
Nabil Yassine Steve Barker Khaled Hayatleh Bhaskar Choubey Rajasekhar Nagulapalli 《Analog Integrated Circuits and Signal Processing》2018,95(3):409-414
This paper proposes a system to detect and measure blink rate to determine fatigue levels. The method involved analysing specific frames to determine that a blink occurred, and then monitoring the time between successive blinks. The program was simulated in python using a Raspberry Pi Zero and a standard USB camera. For the blink rate detection block, a gate level schematic was implemented in Cadence software using 65 nm CMOS technology. The design was based around an asynchronous 6-bit based edge counter which was designed using D-flip-flops. The simulation calculated the average blink rate and compared this to the most recent blink rate. The outcome would determine if an alarm signal should be sent to the alarm. The system consumed 130 μA from a 1.2 V power supply. 相似文献
32.
Danish Mahmood Nadeem Javaid Imran Ahmed Nabil Alrajeh Iftikhar Azim Niaz Zahoor Ali Khan 《国际能源研究杂志》2017,41(14):2074-2090
In this paper, a multi‐agent‐based locally administrated power distribution hub (PDH) for social welfare is proposed that optimizes energy consumption, allocation, and management of battery energy storage systems (ESSs) for a smart community. Initially, formulation regarding optimum selection of a power storage system for a home (in terms of storage capacity) is presented. Afterwards, the concept of sharing economy is inducted in the community by demonstrating PDH. PDH is composed of multiple small‐scale battery ESSs (each owned by community users), which are connected together to form a unified‐ESS. Proposed PDH offers a localized switching mechanism that takes decision of whether to buy electricity from utility or use unified‐ESS. This decision is based on the price of electricity at ‘time of use’ and ‘state of charge’ of unified‐ESS. In response to power use or share, electricity bills are created for individual smart homes by incrementing or decrementing respective submeters. There is no buying or selling of power from PDH; there is power sharing with the concept of ‘no profit, no loss’. The objective of the proposed PDH is to limit the purchase of electricity on ‘high priced’ hours from the utility. This not only benefits the utility at crucial hours but also provides effective use of power at the demand side. The proposed multi‐agent system depicts the concept of sharing power economy within a community. Finally, the proposed model is analyzed analytically, considering on‐peak, off‐peak, and mid‐level (mid‐peak) prices of a real‐time price signal during 24 h of a day. Results clearly show vital financial benefits of ‘sharing power economy’ for end users and efficient use of power within the smart community. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
33.
34.
The aim of this paper is to shed light on complementarities and substitutions between various types of innovation capabilities in knowledge-intensive-based service (KIBS) firms. The data used in this study are the responses of 2,625 innovative firms to the 2003 Statistics Canada Innovation Survey on services. The empirical results suggest the presence of three patterns of complementary innovation capabilities, one pattern of substitute activities and finally, four patterns of innovation capabilities that are independent from each other. Hence, the results suggest the presence of complementarities: first, between internal R&D, external R&D, acquisition of equipment and machinery, and marketing activities; second, between external R&D, acquisition of equipment and machinery, acquisition of external knowledge and marketing activities; third, between acquisition of equipment and machinery, acquisition of external knowledge and marketing activities. Such complementarities lead to the conclusion that, in practice, managers of KIBS firms consider the consolidation of these capabilities jointly instead of separately. The paper also discusses issues related to patterns of capabilities that are substitutes and independent from each other. The results of this study also show significant heterogeneity in the determinants of the different patterns of innovation capabilities. 相似文献
35.
Nabil B. Sada Mohammed A. Al Nawafleh 《Journal of Mechanical Science and Technology》2009,23(8):2277-2284
Round bars of 13.6 mm diameter made from low alloy steel were sprayed by hard-coating Lubrotec 19985 under the following spraying
parameters: the rotation speed varied from 500 to 900 rpm, the feeding speed from 0.1 to 1.0 mm/rev, and the nozzle tip distance
from 100 to 200 mm; the sprayed bars were then subjected to bending test. Depending on the thickness of the produced coating,
the modulus of elasticity and yield bending stress of the coating were calculated by applying the bending deflection formula
and an equivalent cross-sectional area technique, respectively. The results obtained indicated that the thickness, hardness,
yield bending stress, and modulus of the elasticity of coating were varied with the variation in spraying parameters. The
optimum spraying parameter was a rotation speed of 700 r.p.m, a nozzle tip distance of 200 mm, and a feed rate of 0.1 mm/rev.
This optimum parameter produced an acceptable thickness of 1.14 mm, a hardness of 148 HV, a bending stress of 404.9 MPa, and
a modulus of elasticity of 91.47 GPa. The results obtained can also help determine the modulus of elasticity and yield bending
stress of the various coating materials when a coated round bar is subjected to the bending test.
This paper was recommended for publication in revised form by Associate Editor Youngseog Lee
Nabil B. Sada was awarded the B.Sc. degree in Mechanical Engineering in 1969, from Baghdad University, Iraq, and Ph.D. degree in Mechanical
Engineering in 1980, from Queen’s University of Belfast, United Kingdom. From 1981 to 1989, Dr. Nabil was a Researcher and
Lecturer at State Enterprise for Mechanical Industries, and at the Department of Mechanical Engineering at Al-Mostansyria
University in Iraq. From 1994 to 1998, he was a Professor at Department of Mechanical Engineering, Al-Tahadi University, Libya.
From 1999 to 2008, he was a Professor at the Department of Mechanical Engineering at Al-Balqa’ Applied University, and at
Tafila Technical University, Jordan. Currently, he is a researcher in Canada.
Mohammed Al-Nawafleh received his B.S. and M.S degrees in Mechanical Engineering from Leningrad Ins-titute of Textile and Light Industry in 1989.
He then received his Ph.D. degree from Sankt-Petersburg State University of Technology and Design, Russia in 1993. From 1997
to 2005, Dr. Nawafleh was a Professor at the Department of Mechanical Engineering at Al-Balqa’ Applied University in Jordan.
From 2005 to 2008, he was a Professor at the Department of Mechanical Engineering at Tafila Technical University. Currently,
he is a Professor at the Department of Civil Engineering at Al-Hussein Bin Talal University, Jordan. 相似文献
36.
Abstract— We theoretically modeled the optical plasmon absorption of anisotropic metallic nanoparticles in a liquid‐crystal host medium. Metallic nanorods and spheroids act as pleochroic dopants with virtually unlimited photostability. Calculations predict that full‐color displays based on nanorod orientation driven by the transition from homogeneous to homeotropic LC alignment are feasible. These displays are expected to have large viewing angles without the need for polarizers or LC anchoring surfaces. 相似文献
37.
Hossein Saiedian Nabil Ghanem Jeyabarathi Natarajan 《Annals of Software Engineering》2002,13(1-4):71-96
The success of building distributed object systems depends on important factors such as architecture, the distributed object model (DOM) selected, and the process adapted in the selection of the DOM. There are a number of DOMs. Although the primary goals of these models are the same, each model has a unique underlying architecture, maturity, and features provided. A critical evaluation of DOMs is thus needed by those organizations that are considering migrating to distributed object computing. The evaluation process can be time-consuming and may drain organizational resources. Most of the current evaluation processes adopted by organizations are not generic enough, and they concentrate only on the problem on hand. Hence, they cannot be used by any other organization, sometimes not even a different project at the same organization. Therefore, a more generalized framework or template is required to evaluate DOMs. This paper proposes a framework to evaluate DOMs. A number of important managerial items such as cost, personnel, and technology resources, training, enterprise changes, and time constraints have been identified, explained, and justified as the evaluation criteria. An evaluation of the most widely used DOMs, CORBA, DCOM, and RMI, is provided using the above criteria. Finally, a case study of a production web-based system is presented to demonstrate the use of the framework. 相似文献
38.
In situ dynamic observations of the deformation and fracture characteristics of alpha/beta brass two-phase bicrystals were made by the solid diffusion method. The results indicated clearly that the crack initiation site was at the interface. The crack propagation direction, in both the alpha and beta phases, was found to be orientation dependent. Complementary experiments on alpha and beta brass single crystals confirmed the theories and results obtained previously on ductile single crystals.On leave from the Mechanical Engineering Department, Al-Azhar University, Cairo, Egypt. 相似文献
39.
Nabil Kamel 《Distributed and Parallel Databases》2000,8(3):297-331
A language for manipulating ASN.1 print files is defined as an addition to the ASN.1 data definition language as specified in the ISO standards 8824 and 8825. The language has syntax similar in spirit to SQL, and provides analogous operations. Together, ASN.1 and the manipulation language define a model that can represent attribute hierarchies, multivalued attributes, optional attributes, both ordered and unordered attributes and tuples, and unnamed attributes—constructs that are absent in the traditional relational model. In addition, the proposed model allows the semantics of order, homogeneity, optionality, choosability, and uniqueness to be attached to constructs and construct elements. The approach is well suited for modeling data where form is important, such as text and flat file databases having ad hoc formats. It also supports modeling relations. The primary motivation for developing this language is to provide a common model for a database integration approach where some of the databases are in the form of formatted flat file text, while others are relational. Although the approach is general and can be applied in many different areas, scientific database and tool integration was the primary motive for its development. 相似文献
40.
A great majority of modern buildings are equipped with Energy Management and Control Systems (EMCS) which monitor and collect operating data from different components of heating ventilating and air conditioning (HVAC) systems. Models derived and tuned by using the collected data can be incorporated into the EMCS for online prediction of the system performance. To that end, HVAC component models with self-tuning parameters were developed and validated in this paper. The model parameters were tuned online by using a genetic algorithm which minimizes the error between measured and estimated performance data. The developed models included: a zone temperature model, return air enthalpy/humidity and CO2 concentration models, a cooling and heating coil model, and a fan model. The study also includes tools for estimating the thermal and ventilation loads. The models were validated against real data gathered from an existing HVAC system. The validation results show that the component models augmented with an online parameter tuner, significantly improved the accuracy of predicted outputs. The use of such models offers several advantages such as designing better real-time control, optimization of overall system performance, and online fault detection. 相似文献