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81.
The validity of an intelligence test is discussed. "The Lowry Reasoning Test Combination has been found to be relatively free of social status bias and to measure intellectual function. It is easily administered and simply scored and does not depend upon a high level of verbal ability. Variance in concept difficulty is obtained by altering combinations of constructs while keeping the verbal material on a uniformly simple level. Whereever such a discriminative and effective selection device is needed the present writers would recommend that the Lowry test be tried." (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
82.
A Secure Function Evaluation (SFE) of a two-variable function f(·,·) is a protocol that allows two parties with inputs x and
y to evaluate f(x,y) in a manner where neither party learns "more than is necessary". A rich body of work deals with the
study of completeness for secure two-party computation. A function f is complete for SFE if a protocol for securely evaluating
f allows the secure evaluation of all (efficiently computable) functions. The questions investigated are which functions are
complete for SFE, which functions have SFE protocols unconditionally and whether there are functions that are neither complete
nor have efficient SFE protocols. The previous study of these questions was mainly conducted from an information theoretic
point of view and provided strong answers in the form of combinatorial properties. However, we show that there are major differences
between the information theoretic and computational settings. In particular, we show functions that are considered as having
SFE unconditionally by the combinatorial criteria but are actually complete in the computational setting. We initiate the
fully computational study of these fundamental questions. Somewhat surprisingly, we manage to provide an almost full characterization
of the complete functions in this model as well. More precisely, we present a computational criterion (called computational
row non-transitivity) for a function f to be complete for the asymmetric
case. Furthermore, we show a matching criterion called computational row transitivity for f to have a simple SFE (based on
no additional assumptions). This criterion is close to the negation of the computational row non-transitivity and thus we
essentially characterize all "nice" functions as either complete or having SFE unconditionally. 相似文献
83.
Multihop wireless systems have the potential to offer improved coverage and capacity over single-hop radio access systems. Standards development organizations are considering how to incorporate such techniques into new standards. One such initiative is the IEEE 802.16j standardization activity, adding relay capabilities to IEEE 802.16 systems. This article provides an overview of this relay-based technology, focusing on some of the most pertinent aspects. In particular, the different modes of operation (transparent and non-transparent), framing structures, and network entry procedures are described. Some consideration of the issues in designing such systems is then given, which highlights when different features within the standard are most appropriate. As these systems are very new, many open issues remain to be resolved. 相似文献
84.
Sadeeq Jan Omer Bin Tauqeer Fazal Qudus Khan George Tsaramirsis Awais Ahmad Iftikhar Ahmad Imran Maqsood Niamat Ullah 《计算机、材料和连续体(英文)》2021,66(1):631-645
Over the last decade, a significant increase has been observed in the use
of web-based Information systems that process sensitive information, e.g., personal, financial, medical. With this increased use, the security of such systems
became a crucial aspect to ensure safety, integrity and authenticity of the data.
To achieve the objectives of data safety, security testing is performed. However,
with growth and diversity of information systems, it is challenging to apply security testing for each and every system. Therefore, it is important to classify the
assets based on their required level of security using an appropriate technique.
In this paper, we propose an asset security classification technique to classify
the System Under Test (SUT) based on various factors such as system exposure,
data criticality and security requirements. We perform an extensive evaluation of
our technique on a sample of 451 information systems. Further, we use security
testing on a sample extracted from the resulting prioritized systems to investigate
the presence of vulnerabilities. Our technique achieved promising results of successfully assigning security levels to various assets in the tested environments and
also found several vulnerabilities in them. 相似文献
85.
Abusabah I. A. Ahmed Hong Cheng Zhang Liangwei Mugahid Omer Xichuan Lin 《Journal of Intelligent and Robotic Systems》2017,87(1):59-80
On-line walking speed control in human-powered exoskeleton systems is a big challenge, the translations of human intention to increase or decrease walking speed in maneuverable human exoskeleton systems is still complex field. In this paper, we propose a novel sensing technique to control the walking speed of the system according to the pilot intentions and to minimize the interaction force. We introduce a new sensing technology “Dual Reaction Force (DRF)” sensors, and explain the methodology of using it in the investigation of walking speed changing intentions. The force signals mismatch successfully applied to control the walking speed of the exoskeleton system according to the pilot intentions. Typical issues on the implementation of the sensory system are experimentally validated on flat terrain walking trails. We developed an adaptive trajectory frequency control algorithm to control the walking speed of HUman-powered Augmentation Lower Exoskeleton (HUALEX) within the human wearer intended speed. Based on the mismatch of DRF sensors, we proposed a new control methodology for walking speed control. Human intention recognition and identification through an sensorized footboard and smart shoe is achieved successfully in this work, the new term heel contact time H C T is main feedback signal for the control algorithm. From the experimental walking trails we found that, the H C T during flat walking ranges from 0.69±0.05 sec and 0.41±0.07 sec while walking speed varies between 1m/s and 2.5m/s. The proposed algorithm used an Adaptive Central Pattern Generators (ACPGs) applied to control joint trajectory frequency, the different walking speeds associated with different functioning of human body CPGs frequency. We validated the proposed control algorithm by simulations on single Degree of Freedom (1-DoF) exoskeleton platform, the simulation results show the efficiency and validated that the proposed control algorithm will provides a good walking speed control for the HUALEX exoskeleton system. 相似文献
86.
Joshua C. Steele Kurt Mahoney Omer Karovic Larry W. Mays 《Water Resources Management》2016,30(5):1605-1620
The design of urban stormwater systems and sanitary sewer systems consists of solving two problems: generating a layout of the system and the pipe design which includes the crown elevations, slopes and commercial pipe sizes. A heuristic model for determining the optimal (minimum cost) layout and pipe design of a storm sewer network is presented. The hierarchical procedure combines a sewer layout model formulated as a mixed-integer nonlinear programming (MINLP) problem which is solved using the General Algebraic Modeling System (GAMS) and a simulated annealing optimization procedure for the pipe design of a generated layout was developed in Excel. The GAMS and simulated annealing models are interfaced through linkage of Excel and GAMS. The pipe design model is based upon the simulated annealing method to optimize the crown elevations and diameter of pipe segments in a storm sewer network using layouts generated using GAMS. A sample scenario demonstrates that using these methods may allow for significant costs saving while simultaneously reducing the time typically required to design and compare multiple storm sewer networks. 相似文献
87.
Reduction of COD in wastewater from an organized tannery industrial region by Electro-Fenton process 总被引:2,自引:0,他引:2
Advanced oxidation processes (AOPs) have led the way in the treatment of aqueous waste and are rapidly becoming the chosen technology for many applications. In this paper, COD reduction potential of leather tanning industry wastewaters by Electro-Fenton (EF) oxidation, as one of the AOPs, was experimentally evaluated. The wastewater sample was taken from an outlet of an equalization basin in a common treatment plant of an organized tannery industrial region in Istanbul, Turkey. Treatment of the wastewater was carried out by an electrochemical batch reactor equipped with two iron electrodes, which were connected parallel to each other. The oxidation process was studied for optimization of H(2)O(2) and the electricity consumptions were observed at different contact times under different pH conditions (3.0, 5.0 and 7.2). In each case, electricity consumption for decreased COD mass was estimated. In this process, COD was reduced by 60-70% within 10 min. By taking into consideration the local sewerage discharge limit, applicability of EF process for the tannery wastewaters was evaluated. 相似文献
88.
Chao Zhao Konstantza Lambrinou Omer Van Der Biest 《Journal of Materials Science》1999,34(8):1865-1871
Unidirectional magnesium aluminosilicate (MAS) glass-ceramic matrix/silicon carbide (SiC) fibre composites were produced,
employing the slurry infiltration-hot pressing technique. The densification and crystallisation behaviour of the (P2O5, B2O3)-containing MAS glass-ceramic matrix was studied in depth. The major result of the matrix study was the construction of a
two-dimensional hot pressing ‘window’ within which MAS/SiC composites were successfully processed. The ‘window’ dimensions,
namely temperature and time, were shown to depend on each other.
This revised version was published online in September 2006 with corrections to the Cover Date. 相似文献
89.
Java RMI, Jini and CORBA provide effective mechanisms for implementing a distributed computing system. Recently many numeral libraries have been developed that take advantage of Java as an object‐oriented and portable language. The widely‐used client‐server method limits the extent to which the benefits of the object‐oriented approach can be exploited because of the difficulties arising when a remote object is the argument or return value of a remote or local method. In this paper this problem is solved by introducing a data object that stores the data structure of the remote object and related access methods. By using this data object, the client can easily instantiate a remote object, and use it as the argument or return value of either a local or remote method. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
90.
An optimization procedure has been developed for branching storm and sanitary sewer systems with a pre-determined layout for determining the minimum total cost. The model was developed within Microsoft Excel using simulated annealing as the optimization procedure. The total cost of the storm sewer system that was obtained with this optimal design procedure was compared to the total cost of the system as obtained from the conventional straight slope design procedure. Applying the simulated annealing optimizer to the design of the branching storm sewer network resulted in a cost savings of over $77,100 or about 7 % (a reduction from $1,117,700 to $1,040,600). These significant savings were realized by simply going an extra step and implementing an optimization technique during the design phase. Use of Excel should enhance the availability and the usage of such an optimization model for the design of storm and sanitary sewer systems by consulting engineers and various agencies. 相似文献