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121.
In this note, a construction of state representations of singular linear time-invariant differential systems is described directly in terms of trajectories. 相似文献
122.
Tariq Mahmood Syed Imran Jami Zubair Ahmed Shaikh Muhammad Hussain Mughal 《Computer Standards & Interfaces》2013,35(1):6-29
In this paper, we implement a provenance-aware system for documenting publications, called PADS. It employs a three-layered provenance hierarchy, which can output diverse types of provenance data related to the research life cycle. From this, we generate different profiles for research ventures, reviewers, and authors. PADS employs the standard Open Provenance Model (OPM) specification for capturing provenance data, and stores this data as ontological instances. We show that data is retrieved without any apparent delay in the execution time of the queries. We also demonstrate how this data can be used to make useful recommendations to the organizers, in order to manage upcoming research ventures. 相似文献
123.
124.
A model set of nonlinear electrostatic equations is analyzed critically; they have been presented earlier to study the short-scale auroral density cavities (SSADC) observed by Freja satellite. It is shown that electron inertial effect is not necessary to obtain solitary structure through electrostatic nonlinear equations. The ion streaming and direction of propagation of the structure seem to be the two parameters that can decide the width of the density cavity. 相似文献
125.
126.
Bourhan Tashtoush Mahmood Tahat Ahmed Al-Hayajneh Victor A. Mazur Doug Probert 《Applied Energy》2001,70(4):980
The performance of an open absorption-system, energized by low-grade heat such as insolation and/or waste heat, has been investigated. This combined evaporative cooler (CEC) [i.e. an indirect evaporative cooler (IEC) together with a direct evaporative-cooler (DEC)] was used to cool the air. A computer simulation of the cooling cycle was devised, so that the performance characteristics of the system could be predicted for a range of operating conditions: the influences of various design-parameters on the coefficient of performance (COP) were also evaluated. The COP of the CEC system was at least 20% greater than those achieved when employing either the IEC or DEC systems alone. 相似文献
127.
Naima Iltaf Abdul Ghafoor Usman Zia Mukhtar Hussain 《Wireless Personal Communications》2014,75(3):1689-1713
The performance of indirect trust computation models (based on recommendations) can be easily compromised due to the subjective and social-based prejudice of the provided recommendations. Eradicating the influence of such recommendation remains an important and challenging issue in indirect trust computation models. An effective model for indirect trust computation is proposed which is capable of identifying dishonest recommendations. Dishonest recommendations are identified by using deviation based detecting technique. The concept of measuring the credibility of recommendation (rather than credibility of recommender) using fuzzy inference engine is also proposed to determine the influence of each honest recommendation. The proposed model has been compared with other existing evolutionary recommendation models in this field, and it is shown that the model is more accurate in measuring the trustworthiness of unknown entity. 相似文献
128.
The purpose of this research is to study the stress corrosion behavior of basalt/epoxy composites under bending loading and
submerged in 5% sulfuric acid corrosive medium. There are limited numbers of research in durability of fiber reinforced polymer
composites. Moreover, studies on basalt fibers and its composites are very limited. In this research, mechanical property
degradation of basalt/epoxy composites under bending loading and submerged in acidic corrosive medium is investigated. Three
states of stress, equal to 30%, 50% and 70% of the ultimate strength of composites, are applied on samples. High stress states
are applied to the samples to accelerate the testing procedure. Mechanical properties degradation consists of bending strength,
bending modulus of elasticity and fracture energy of samples are examined. Also, a normalized strength degradation model for
stress corrosion condition is presented. Finally, microscopic images of broken cross sections of samples are examined. 相似文献
129.
Gordon Rugg Malcolm Eva Atiya Mahmood Nazia Rehman Stephanie Andrews & Sarah Davies 《Information Systems Journal》2002,12(3):215-229
Abstract. Eliciting information about organizational culture is an important part of system analysis and design. However, eliciting knowledge of this sort is difficult. Laddering is an established technique that is particularly suitable for eliciting information about goals and for eliciting explanations, which are important issues when investigating organizational culture. This paper describes the method, its strengths and limitations, its use in several case studies and its relation to other elicitation techniques. Recommendations for further work are given. 相似文献
130.
Comparison of component method with experimental tests for flush end-plate connections using hot-rolled perwaja steel sections 总被引:1,自引:1,他引:0
A component method has been introduced by Steel Construction Institute to predict the moment resistance of partial strength
connection. The design philosophy is taken directly from Eurocode 3 with strength checks on bolts, welds, and steel which
have been modified to comply with BS 5950-1:2000. The accuracy of the method however needs to be validated with the experimental
tests especially for hot-rolled sections other than typical British Section (BS). Six experimental tests on beam-to-column
connections have been carried out for Flush End-Plate (FEP) connections consisting of variable parameters such as thickness
of end-plate, size and number of bolts, size of columns, and beams. The tests were set-up using local hot-rolled steel sections
known as Perwaja Section (PS) for beams and columns instead of typical British Section (BS). The strength of materials for
end-plate, column and beam sections were tested for tensile strength and used in predicting the moment resistance for component
method. The moment versus rotation of the test results were plotted and compared with the moment resistance derived from component
method. The study concluded that the moment resistance of the tested flush end-plate connections was higher than the predicted
moment resistance from component method which showed good agreement between the two moments. The study also concluded that
the tested FEP connections met the requirements and criteria of partial strength connections. 相似文献