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991.
Joan?CahillEmail author Nick?Mc?Donald Captain?Gabriel?Losa 《Cognition, Technology & Work》2011,13(1):43-66
A safe flight starts with effective performance of the pre-flight flight planning and briefing task. However, several problems
related to the execution of this task can be identified. Potentially, the introduction of an improved flight plan provides
an opportunity to improve the quality and availability of information provided to Flight Crew, thereby enhancing the quality
of crew briefings. The proposed risk-based, intelligent flight plan is designed from the perspective of the current operational
concept (e.g. fixed routes and ATC managerial role for separation), and associated airline Flight Planning and Dispatch functions.
In this case, the focus is sharing information across specific airline stakeholders (e.g. Flight Operations Management and
Safety functions) and Maintenance, to support a safe and efficient flight operation. Overall, the introduction of this new
flight plan will result in the definition of new operational and organisational processes, along with a new way of performing
the pre-flight, planning and briefing task. It is anticipated that this will impact positively on the operational and safety
outcome of the flight. 相似文献
992.
(O)mür (O)cal 《国际自动化与计算杂志》2011,8(2):254-261
The coefficient diagram method (CDM) is one of the most effective control design methods. It creates control systems that
are very stable and robust with responses without the overshoot and small settling time. Furthermore, all control parameters
of the control systems are changed by varying some adjustment parameters in CDM depending on the demands. The model reference
adaptive systems (MRAS) are the systems that follow and change the control parameters according to a given model reference
system. There are several methods to combine the CDM with MRAS. One of these is to use the MRAS parameters as a gain of the
CDM parameters. Another is to directly use the CDM parameters as the MRAS parameters. In the industrial applications, the
system parameters can be changed frequently, but if the controller, by self-tuning, recalculates and develops its own parameters
continuously, the system becomes more robust. Also, if the poles of the controlled systems approach the jw axis, the response of the closed-loop MRAS becomes more and more insufficient. In order to obtain better results, CDM is
combined with a self-tuning model reference adaptive system. Systems controlled by a model reference adaptive controller give
responses with small or without overshoot, have small settling times, and are more robust. Thus, in this paper, a hybrid combination
of MRAS and CDM is developed and two different control structures of the control signal are investigated. The two methods
are compared with MRAS and applied to real-time process control systems. 相似文献
993.
994.
Dragan Iveti? Author Vitae Author Vitae Branko Markoski Author Vitae 《Computers & Electrical Engineering》2010,36(1):169-179
This paper presents a novel video augmentation approach: a video recording of a real entity augmented by structured data. This augmented video is a self-contained entity integrating values of perceptible and non-perceptible attributes of the same real entity. It simplifies data search, storage and management. Streaming, sharing, collaboration and synchronization are also simplified by the fact that the structured data (so-called augmented data) are integrated in the video file and therefore only one file needs to be manipulated. Our approach was applied to address the issues which road engineers experience while using the ROad Measurement and Data Acquisition System (ROMDAS). The ROMDAS system collects and analyses the road-condition state through video recordings and the data corresponding acquired by specific measuring devices. Currently, however, road engineers have to search the videos manually in order to find details of interest provided by the analysis of the data measured due to the separation of the video from the data. The ROMDAS system manages a large collection of road-condition data. It does not offer history management of video recordings of the same road captured at different time. We present this hybrid video augmentation system: the Augmented Video stream Framework (AVF). It allows creation, search, history management and playback of such augmented video files for effective road surveying based on the discrete data recorded in parallel to the video recordings. The AVF provides road engineers with effective and more comfortable perceptible and non-perceptible data search, storage and history management to be used for (collaborative) road inspection and maintenance. 相似文献
995.
?pek Abas?kele? 《Computers & Electrical Engineering》2010,36(1):114-131
Recent advances in the development of optical technologies suggest the possible emergence of broadcast-based optical interconnects within cache-coherent distributed shared memory (DSM) multiprocessor architectures. It is well known that the cache-coherence protocol is a critical issue in designing such architectures because it directly affects memory latencies. In this paper, we evaluate via simulation the performance of three directory-based cache-coherence protocols; strict request-response, intervention forwarding and reply forwarding on the Simultaneous Optical Multiprocessor Exchange Bus (SOME-Bus), which is a low-latency and high-bandwidth broadcast-based fiber-optic interconnection network supporting DSM. The simulated system contains 64 nodes, each of which has a processor, a cache controller, a directory controller and an output channel. Simulations have been conducted for each protocol to measure average processor utilization, average network latency and average number of packets transferred over the network for varying values of the important DSM parameters such as the ratio of the mean channel service time to mean thread run time (T/R), probability of a cache block being in modified state {P(M)}, the fraction of write misses {P(W)} and home node contention rate. The results reveal that for all cases, except for low values of P(M), intervention forwarding gives the worst performance (lowest processor utilization and highest latency). The performance of strict request-response and reply forwarding is comparable for several values of the DSM parameters and contention rate. For a contention rate of 0%, the increase of P(M) makes reply forwarding perform better than strict request-response. The performance of all protocols decreases with the increase of P(W) and contention rate. However, the performance of strict request-response is the least affected among other protocols due to the negative impact of the increase of P(W) and contention rate. Therefore, for the full contention case (i.e. contention rate of 100%); for low values of P(M), or for mid values of P(M) and high values of P(W), strict request-response performs better than reply forwarding. These results are significant in the sense that they provide an insight to multiprocessor architecture designers for comparing the performance of different directory-based cache-coherence protocols on a broadcast-based interconnection network for different values of the DSM parameters and varying rates of contention. 相似文献
996.
Explanation and reliability of prediction models: the case of breast cancer recurrence 总被引:1,自引:1,他引:0
Erik ?trumbelj Zoran Bosni? Igor Kononenko Branko Zakotnik Cvetka Gra?i? Kuhar 《Knowledge and Information Systems》2010,24(2):305-324
In this paper, we describe the first practical application of two methods, which bridge the gap between the non-expert user
and machine learning models. The first is a method for explaining classifiers’ predictions, which provides the user with additional
information about the decision-making process of a classifier. The second is a reliability estimation methodology for regression
predictions, which helps the users to decide to what extent to trust a particular prediction. Both methods are successfully
applied to a novel breast cancer recurrence prediction data set and the results are evaluated by expert oncologists. 相似文献
997.
Eila Ovaska Antti Evesti Katja Henttonen Marko Palviainen Pekka Aho 《Information and Software Technology》2010,52(6):577-601
Modelling and evaluating quality properties of software is of high importance, especially when our every day life depends on the quality of services produced by systems and devices embedded into our surroundings. This paper contributes to the body of research in quality and model driven software engineering. It does so by introducing; (1) a quality aware software architecting approach and (2) a supporting tool chain. The novel approach with supporting tools enables the systematic development of high quality software by merging benefits of knowledge modelling and management, and model driven architecture design enhanced with domain-specific quality attributes. The whole design flow of software engineering is semi-automatic; specifying quality requirements, transforming quality requirements to architecture design, representing quality properties in architectural models, predicting quality fulfilment from architectural models, and finally, measuring quality aspects from implemented source code. The semi-automatic design flow is exemplified by the ongoing development of a secure middleware for peer-to-peer embedded systems. 相似文献
998.
In this paper, a hybrid intelligent morphological approach is presented for stock market forecasting. It consists of a hybrid
intelligent model composed of a Modular Morphological Neural Network (MMNN) and a Modified Genetic Algorithm (MGA), which
searches for the minimum number of time lags for a correct time series representation, as well as by the initial weights,
architecture and number of modules of the MMNN. Each element of the MGA population is trained via Back Propagation (BP) algorithm
to further improve the parameters supplied by the MGA. Initially, the proposed method chooses the most tuned prediction model
for time series representation, then it performs a behavioral statistical test in the attempt to adjust time phase distortions
that appear in financial time series. An experimental analysis is conducted with the proposed method using four real world
time series and five well-known performance measurements, demonstrating consistent better performance of this kind of morphological
system. 相似文献
999.
?smail Dinçer 《Advances in Engineering Software》2011,42(4):160-171
Determination of deformation modulus and coefficient of subgrade reaction of soils have major importance, whether the projects are in design, and construction or compaction assessment stage of earth filling structures. Plate load test is one of the frequently used method to directly determine the parameters but the method is both costly and time consuming. For this reason, this paper is concerned with the applications of artificial neural networks (ANN) and simple-multiple regression analysis to predict deformation modulus and coefficient of subgrade reaction of compacted soils from compaction parameters (such as maximum dry density (MDD) and optimum moisture content (OMC), field dry density (FDD), and field moisture content (FMC)). Regression analysis and artificial neural network estimation indicated that there are acceptable correlations between deformation modulus and coefficient of subgrade reaction and these parameters. Artificial neural networks model exhibits higher performance than traditional statistical model for predicting deformation modulus and coefficient of subgrade reaction. 相似文献
1000.
In this study, a novel OFF-set based direct-cover Exact Minimization Algorithm (EMA) is proposed for single-output Boolean functions represented in a sum-of-products form. To obtain the complete set of prime implicants covering the given Target Minterm (ON-minterm), the proposed method uses OFF-cubes (OFF-minterms) expanded by this Target Minterm. The amount of temporary results produced by this method does not exceed the size of the OFF-set. In order to achieve the goal of this study, which is to make faster computations, logic operations were used instead of the standard operations. Expansion OFF-cubes, commutative absorption operations and intersection operations are realized by logic operations for fast computation. The proposed minimization method is tested on several classes of benchmarks and then compared with the ESPRESSO algorithm. The results show that the proposed algorithm obtains more accurate and faster results than ESPRESSO does. 相似文献