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131.
The introduction of Internet and Information and communication Technologies (ICT) in offices is a global phenomenon that transformed
white-collar worker job demands. Although there are several studies of e-skills and mental workload for central countries,
there is a lack of similar studies for the Latin American context. An online snowball sampled (n = 352) survey was developed and validated by the authors (internal consistency = 0.7). We characterized ICT worker profiles
from e-skills and these dimensions: attitudes toward, resources usage and technology dependency. Mental Strain was assessed with raw task load index (RTLX) and correlated with the proposed profiles by means of paired
T-tests and Mann–Whitney Tests. The sample was characterized by 7.2% of non visual display terminal users and 92.8% of visual
display terminal, ICT skilled users. Of the latter, 30.7% were ICT practitioners, 30.4% were ICT Users and 27.2% were E-Business
Users. Non VDT users’ mental strain was statistically meaningful smaller than VDT–ICT skilled users’ mental workload. No statistical
differences were found in RTLX results when comparing ICT skilled user profiles. Non VDT users can be identified from ICT
skilled Users by their lower ITC Dependency and minor use of ICT resources. There were no differences in those dimensions
among ICT skilled Profiles. Attitude toward these technologies was a distinct factor for ICT Users in relation to ICT Practitioners
and ITC Business Users. The application of this tool in peripheral and central countries would allow a complete ergonomical
characterization of white-collar workers within the Information Society. 相似文献
132.
Franco Cicirelli Angelo Furfaro Andrea Giordano Libero Nigro 《Simulation Modelling Practice and Theory》2011,19(1):283-300
RePast is a popular agent toolkit with proven capabilities to fulfil the modelling challenges of large multi-agent systems (MASs). The toolkit, though, is normally used on a standalone workstation and therefore its practical use can be constrained (in space and time) by the limited available computing resources. This paper proposes an original approach – HLA_ACTOR_REPAST – aimed to distributing RePast models for high-performance simulation of complex scalable models. Novel in HLA_ACTOR_REPAST is an exploitation of a lean actor infrastructure implemented in Java. Actors bring to RePast agents such features as migration, location-transparent naming, efficient communications, and a control-centric framework. Actors can be orchestrated by an in-the-large custom control structure which is in charge of ensuring the necessary message causality constraints. Distribution and time management concerns depend on the IEEE standard HLA middleware. The paper first discusses details of the software engineering process underlying the development of HLA_ACTOR_REPAST. The mapping techniques, assisted by Java text annotations and aspect-oriented programming, try to minimize “code intrusions” in the original model and favour model transparency. The paper then furnishes some experimental data which witness the good performance results achieved by applying HLA_ACTOR_REPAST to a distributed version of a classic MAS benchmark model. 相似文献
133.
When programmers need to modify third‐party applications, they frequently do not have access to their source code. In such cases, DLL injection and API hooking are techniques that can be used to modify applications without intervening into their source code. The commonly used varieties of injection and hooking approaches have many practical limitations: they are inconvenient for a programmer to implement, do not work reliably in conjunction with all applications and with certain low‐level machine instructions. In this paper we present two novel approaches to DLL injection and API hooking, which we call Debugger‐aided DLL injection and Single Instruction Hooking. Our approaches overcome the limitations of the state‐of‐the art approaches. Despite incurring greater execution times, our approach allows extending of the applications in situations where the comparable approaches fail. As such, it has a notable practical value for beneficial practical applications of injection and hooking approaches, which are present in malware detection programs and computer security tools. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
134.
Combinatorial testing is as an effective testing technique to reveal failures in a given system, based on input combinations
coverage and combinatorial optimization. Combinatorial testing of strength
t (t ≥ 2) requires that each t-wise tuple of values of the different system input parameters is covered by at least one test case. Combinatorial test suite generation
algorithms aim at producing a test suite covering all the required tuples in a small (possibly minimal) number of test cases,
in order to reduce the cost of testing. The most used combinatorial technique is the pairwise testing (t = 2) which requires coverage of all pairs of input values. Constrained combinatorial testing takes also into account constraints
over the system parameters, for instance forbidden tuples of inputs, modeling invalid or not realizable input values combinations. In this paper a new approach to combinatorial
testing, tightly integrated with formal logic, is presented. In this approach, test predicates are used to formalize combinatorial
testing as a logical problem, and an external formal logic tool is applied to solve it. Constraints over the input domain
are expressed as logical predicates too, and effectively handled by the same tool. Moreover, inclusion or exclusion of select
tuples is supported, allowing the user to customize the test suite layout. The proposed approach is supported by a prototype
tool implementation and results of experimental assessment are also presented. 相似文献
135.
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138.
N. Lilić I. Obradović A. Cvjetić 《Engineering Applications of Artificial Intelligence》2010,23(4):453-462
Analysis of safety in surface coal mines represents a very complex process. Published studies on mine safety analysis are usually based on research related to accidents statistics and hazard identification with risk assessment within the mining industry. Discussion in this paper is focused on the application of AI methods in the analysis of safety in mining environment. Complexity of the subject matter requires a high level of expert knowledge and great experience. The solution was found in the creation of a hybrid system PROTECTOR, whose knowledge base represents a formalization of the expert knowledge in the mine safety field. The main goal of the system is the estimation of mining environment as one of the significant components of general safety state in a mine. This global goal is subdivided into a hierarchical structure of subgoals where each subgoal can be viewed as the estimation of a set of parameters (gas, dust, climate, noise, vibration, illumination, geotechnical hazard) which determine the general mine safety state and category of hazard in mining environment. Both the hybrid nature of the system and the possibilities it offers are illustrated through a case study using field data related to an existing Serbian surface coal mine. 相似文献
139.
We investigated intrinsic noise in plasmonic sensors caused by adsorption and desorption of gaseous analytes on the sensor
surface. We analyzed a general situation when there is a larger number of different analyte species. We applied our model
to calculate various analyte mixtures, including some environmental pollutants, toxic and dangerous substances. The spectral
density of mean square refractive index fluctuations follows a dependence similar to that of generation-recombination noise
in photodetectors, flat at lower frequencies and sharply decreasing at higher. Some of the calculated noise levels are well
within the detection range of conventional surface plasmon resonance sensors. An AD noise peak is observed in temperature
dependence of mean square refractive index fluctuations, thus sensor operating temperature may be optimized to obtain larger
signal to noise ratio. A significant property of AD noise is its rise with the decreasing plasmon sensor area, which means
that it will be even more pronounced in modern nanoplasmonic devices. Our consideration is valid both for conventional surface
plasmon resonance devices and for general nanoplasmonic devices. 相似文献
140.
Waser J Fuchs R Ribicić H Schindler B Blöschl G Gröller E 《IEEE transactions on visualization and computer graphics》2010,16(6):1458-1467
In this paper we present World Lines as a novel interactive visualization that provides complete control over multiple heterogeneous simulation runs. In many application areas, decisions can only be made by exploring alternative scenarios. The goal of the suggested approach is to support users in this decision making process. In this setting, the data domain is extended to a set of alternative worlds where only one outcome will actually happen. World Lines integrate simulation, visualization and computational steering into a single unified system that is capable of dealing with the extended solution space. World Lines represent simulation runs as causally connected tracks that share a common time axis. This setup enables users to interfere and add new information quickly. A World Line is introduced as a visual combination of user events and their effects in order to present a possible future. To quickly find the most attractive outcome, we suggest World Lines as the governing component in a system of multiple linked views and a simulation component. World Lines employ linking and brushing to enable comparative visual analysis of multiple simulations in linked views. Analysis results can be mapped to various visual variables that World Lines provide in order to highlight the most compelling solutions. To demonstrate this technique we present a flooding scenario and show the usefulness of the integrated approach to support informed decision making. 相似文献