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1.
The threat of cyber attacks motivates the need to monitor Internet traffic data for potentially abnormal behavior. Due to the enormous volumes of such data, statistical process monitoring tools, such as those traditionally used on data in the product manufacturing arena, are inadequate. “Exotic” data may indicate a potential attack; detecting such data requires a characterization of “typical” data. We devise some new graphical displays, including a “skyline plot,” that permit ready visual identification of unusual Internet traffic patterns in “streaming” data, and use appropriate statistical measures to help identify potential cyberattacks. These methods are illustrated on a moderate-sized data set (135,605 records) collected at George Mason University.  相似文献   

2.
This study considers those questions posed by students during e-mail “tutorials” to elicit information from “guest lecturers” and the use of that information by students in their essays. The “tutorials” were conducted for students in the U.K. by a “guest lecturer” in France. The “guest lecturer” was accredited as a tutor on the module for which the students were enrolled, and participated in the module by the provision of lecture notes prior to the e-mail tutorials. Data for the study, drawn from a comparative education assignment set for undergraduate students enrolled on the module, comprised surveys of students' perceived IT capabilities and attitudes towards IT, analyses of students' questions and analyses of students' essays. The findings of the study indicate (1) that tutees tend to pose questions to elicit information or clarification rather than to elicit the viewpoint or opinions of the “guest lecturer” and (2) that two-thirds of tutees' essays cited information elicited from the “guest lecturer”.  相似文献   

3.
We show that the negative feedback interconnection of two causal, stable, linear time-invariant systems, with a “mixed” small gain and passivity property, is guaranteed to be finite-gain stable. This “mixed” small gain and passivity property refers to the characteristic that, at a particular frequency, systems in the feedback interconnection are either both “input and output strictly passive”; or both have “gain less than one”; or are both “input and output strictly passive” and simultaneously both have “gain less than one”. The “mixed” small gain and passivity property is described mathematically using the notion of dissipativity of systems, and finite-gain stability of the interconnection is proven via a stability result for dissipative interconnected systems.  相似文献   

4.
As digital interfaces increasingly mediate our access to information, the design of these interfaces becomes increasingly important. Designing digital interfaces requires writers to make rhetorical choices that are sometimes technical in nature and often correspond with principles taught in the computer science subfield of human-computer interaction. We propose that an HCI-informed writing pedagogy can complicate for both writing and computer science students the important role audience should play when designing traditional and digital interfaces. Although it is a subtle shift in many ways, this pedagogy seemed to complicate student understanding of the relationship between audience and the texts/interfaces they created: it was not just the “human” (beliefs, attitudes, values, demographics) or the “computer” (the software or hardware or other types of mediation) that mattered but rather the “interaction” between the two. First we explore some of the ways in which writing code and writing prose have merged and paved the way for an HCI-informed writing pedagogy. Next we examine some parallels between human-computer interaction principles and composition principles. Finally, we refer to assignments, student responses, and anecdotal evidence from our classes where an HCI-informed writing pedagogy drew—or could have drawn—student attention more acutely to various audience-related technical and rhetorical interface design choices.  相似文献   

5.
“Walkthrough” and “Jogthrough” techniques are well known expert based methodologies for the evaluation of user interface design. In this paper we describe the use of “Graphical” Jogthrough method for evaluating the interface design of the Network Simulator, an educational simulation program that enables users to virtually build a computer network, install hardware and software components, make the necessary settings and test the functionality of the network. Graphical Jogthrough is a further modification of a typical Jogthrough method, where evaluators' ratings produce evidence in the form of a graph, presenting estimated proportion of users who effectively use the interface versus the time they had to work with it in order to succeed effectiveness. We comment on the question: “What are the possible benefits and limitations of the Graphical Jogthrough method when applied in the case of educational software interface design?” We present the results of the evaluation session, and concluding from our experience we argue that the method could offer designers quantitative and qualitative data for formulating a useful (though rough in some aspects) estimation about the novice–becoming–expert pace that end users might follow when working with the evaluated interface.  相似文献   

6.
We present a calculus for modelling “environment-aware” computations, that is computations that adapt their behaviour according to the capabilities of the environment. The calculus is an imperative, object-based language with extensible objects, equipped with a labelled transition semantics. A notion of bisimulation, lifting to computations a correspondence between the capabilities of different environments, is provided. Bisimulation can be used to prove that a program is “cross-environment”, i.e., it has the same behaviour when run in different environments.  相似文献   

7.
This paper describes the information system used to search for a potential matrimonial partner. The search is based on comparison of the subject's record, which consists of his/her answers to about 400 items of a specially designed questionnaire, to the records of the potential partners. The basic principle of the system is representation of the set of candidates for the client with psychological warnings about potential “conflict zones” in relationships between client and candidate rather than a ranking of candidates based on hypothetical “psychological compatibility” indices.  相似文献   

8.
A number of diagnostic scales have been developed in recent years to assess Internet addiction. To better understand the structure, validity, and reliability of such assessment instruments, Young’s Internet Addiction Test (IAT) was evaluated using a confirmatory approach.Data collected through a survey of 410 Hong Kong university undergraduates was subjected to exploratory factor analysis and data from a hold-out sample was analyzed using confirmatory factor analysis in order to assess the psychometric properties and factor structure of the IAT scale. Three dimensions, namely, “Withdrawal and Social Problems”, “Time Management and Performance”, and “Reality Substitute” were extracted.These dimensions were then correlated with a number of criterion variables, including academic performance, online activities, gender, and Internet usage. The results show that academic performance was negatively correlated with the Internet addiction scores. The degree of Internet addiction was also found to vary across different types of online activity, with people engaged in cyberrelationships and online gambling having higher Internet addiction scores.  相似文献   

9.
Induction based fluidics (IBF), a new, simple patented approach for transporting liquids in the micro and the macro world, is discussed. Electric fields are shown to energize liquid/s in a container/s to execute an array of purposes. IBF is shown uniquely to energize N liquids in simple off the shelf devices, inductively. We discuss calibration and other issues, as we demonstrate how simple devices can dispense nanoliters and microliters with high precision and accuracy. Furthermore, we show preliminary single and eight channel data for the Zip Tip™ made by Millipore where the device transports liquids “electrically.” We briefly consider how such new devices, “electric” Zip Tips™, might automate desalting and the placement of digests for MALDI TOF analysis.  相似文献   

10.
The paper presents an approach to characterizing a “stop–flow” mode of sensor array operation. The considered operation mode involves three successive phases of sensors exposure: flow (in a stream of measured gas), stop (in zero flow conditions) and recovery (in a stream of pure air). The mode was characterized by describing the distribution of information, which is relevant for classification of measured gases in the response of sensor array. The input data for classifier were the sets of sensors output values, acquired in discrete time moments of the measurement. Discriminant Function Analysis was used for data analysis. Organic vapours of ethanol, acetic acid and ethyl acetate in air were measured and classified. Our attention was focused on data sets which allowed for 100% efficient recognition of analytes. The number, size and composition of those data sets were examined versus time of sensor array response. This methodology allowed to observe the distribution of classification-relevant information in the response of sensor array obtained in “stop–flow” mode. Hence, it provided for the characterization of this mode.  相似文献   

11.
An integrated learning object, a web-based inquiry environment “Young Scientist” for basic school level is introduced by applying the semiosphere conception for explaining learning processes. The study focused on the development of students’ (n = 30) awareness of the affordances of learning objects (LO) during the 3 inquiry tasks, and their ability of dynamically reconstructing meanings in the inquiry subtasks through exploiting these LO affordances in “Young Scientist”. The problem-solving data recorded by the inquiry system and the awareness questionnaire served as the data-collection methods.It was demonstrated that learners obtain complete awareness of the LO affordances in an integrated learning environment only after several problem-solving tasks. It was assumed that the perceived task-related properties and functions of LOs depend on students’ interrelations with LOs in specific learning contexts. Learners’ overall awareness of certain LO affordances, available in the inquiry system “Young Scientist”, developed with three kinds of patterns, describing the hierarchical development of the semiosphere model for learners. The better understanding of the LO affordances, characteristic to the formation of the functioning semiosphere, was significantly related to the advanced knowledge construction during these inquiry subtasks that presumed translation of information from one semiotic system to another. The implications of the research are discussed in the frames of the development of new contextual gateways for learning with virtual objects. It is assumed that effective LO-based learning has to be organized through pedagogically constrained gateways by manifesting certain LO affordances in the context in order to build up the dynamic semiosphere model for learners.  相似文献   

12.
In this paper, we identify key challenges faced by computer-based assessment (CBA) in secondary education and we put forward a framework of design considerations: design with the students and teachers, select the most appropriate media platform and plan an evolution rather than a revolution of prior practices. We present the CBA application ‘MyTest’ which was developed using the participatory methodology We!Design, with the collaboration of 31 students and teachers. The application is targeted for the Tablet PC platform, provides “digital ink” capabilities and supports both closed-type and open questions, facilitating the transfer of traditional assessment practices to CBA. Both students and teachers were excited about the design sessions, and they asserted that they would rely more on educational software designed using this approach. The comparison of the ‘MyTest’ application with an assessment application developed with the same participatory methodology and the involvement of 40 undergraduate students revealed dissimilar expectations and needs of high school and undergraduate students that are often disguised or misinterpreted. A pilot evaluation of the application in real learning conditions was conducted with 31 students using Tablet PCs and with 37 students using traditional PCs. Interestingly, the Tablet PC platform rendered the ‘MyTest’ application more useful and usable to the students, validating our claims.  相似文献   

13.
Introductory students “brainstormed” experiments on subliminal messages and behavior, then evaluated them in terms of ethics, practicality, measurement, and control. The instructor used Authorware Professional and a Macintosh IIcx to implement five student-generated experiments in which students served as subjects. The pedagogical rationale for the exercise was to give students a sense of investment and ownership in the process of scientific inquiry, to “create a demand” for knowledge of statistics and experimental methods, and to make a convincing case for empiricism as a way of knowing. The exercise generated enthusiasm, produced meaningful discussions, and increased students' understanding of experimentation, measurement, control, and statistics. It was concluded that providing students with this experience would not have been possible without a sophisticated authoring system, and that this student-centered discovery oriented approach may be used effectively in a number of natural science and social science courses where on-line experimentation is appropriate.  相似文献   

14.
Technology does indeed matter to writing—and in significant ways. But how it matters can vary, depending on the particular technology, the habits and attitudes of the individual writer, and the context of learning and use. Here I employ a personal narrative (“a cyberwriter’s tale”) to track my development as a writer over time—from handwriting to typewriting to cyberwriting—and to show how each new writing technology influenced my practices and products. I argue finally for a cyborgian, posthumanist view of writing technologies. Such a view does not isolate the technological tool as an abstracted machine apart from human use, but insists on defining technology as use—as the human and machine working in concert (joined at the interface) and writing in a particular social, political, and rhetorical context.  相似文献   

15.
16.
This paper explores the Cyber-Psychological and Cyber-Geographic aspects of hacking and hacktivism. An examination of the literature related to hackers and hacking reveals a complex nexus of spatial (including cyber-spatial such as “Notopia”) and psychological aspects of hacking, from which emerges a central question of how humans perceive and manipulate their cyber-identities. Concealing (real and cyber) identities is typical in hacking. With our progressive acculturation with identity-less and place-less modes of existence, our cyber-identities through time may be studied from within John Locke’s criterion of “memory” and the spatial-geographical criterion of identity.  相似文献   

17.
One salient impact of information technology on students' lives is the ever-increasing use of the Internet. Although there exist many reports in the media regarding the unhealthy Internet use among students, research is still limited and has mainly relied upon on-line self-selected reports on Internet dependency or “Internet addiction”. This paper attempts to look into the alleged Internet dependency within the Eriksonian psychosocial development framework. The results of a survey of the Internet use among 217 students in an Australian regional university are reported. The measures of patterns of the Internet use were correlated with that of psychosocial maturity and self-efficacy. The results showed that the Internet dependency seemed to be independent of the psychosocial maturity and the general perceived self-efficacy. A factor analysis extracted six factors from a set of 28 Internet experience-related questions and indicated that the Internet dependency could be of a multifaceted nature. The findings and their implications were discussed and a contextual perspective was proposed.  相似文献   

18.
This essay examines how students of African descent at a predominantly black college on the East Coast digitally perform their ethnic identities and rhetorics in a freshman composition course. The essay begins by showing how multiple uses of signifying frame students’ Blackboard discussions where they use a type of trickster motif to enact their agreements, disagreements, challenges, and questions, very much akin to Flava Flav's initial cultural role as part of the Rap/activist group, Public Enemy. Students’ online writing groups are then examined by focusing on one particular group, the “Black Long Distance Writers,” whose title signifies and signals the work of the African American writer and activist, John Oliver Killens, most notably, his seminal 1973 essay, “Wanted: Some Black Long Distance Runners.” The understandings of these “Black Long Distance Writers” bear the most powerful definition of literacy and computer-based writing instruction because their framework is not contingent upon making digitally divided minorities more technologically advanced and better at one type of English, its culture of power, or its academic discourses. Instead, these students experience rhetoric and writing as a way to alter the ways that knowledge is constructed for them and about them, “revocabularizing” the academy and its technologies. Such freshman writers are re-envisioned in this kind of cyberspace as constructors of and co-participants in black intellectual and rhetorical traditions … now AfroDigitized.  相似文献   

19.
Design-patterns and design-principles represent two approaches, which elicit design knowledge from successful learning environments and formulate it as design guidelines. The two approaches are fairly similar in their strategies, but differ in their research origins. This study stems from the design-principles approach, and explores how learning is affected by curriculum-materials designed according to two main design-principles: (a) engage learners in peer instruction, and (b) reuse student artifacts as resource for further learning. These principles were employed in three higher-education courses and examined with 385 students. Data analysis was conducted in two trajectories: In the “bird’s eye view” trajectory we used a “feature” unit of analysis to illustrate how learning was supported by features designed according to the two design-principles in each of the courses. In the “design-based research” trajectory we focused on one feature, a web-based Jigsaw activity, in a philosophy of education course, and demonstrated how it was refined via three design iterations. Students were required to specialize in one of three philosophical perspectives, share knowledge with peers who specialized in other perspectives, and reuse the shared knowledge in new contexts. Outcomes indicated that the design in the first iteration did not sufficiently support student ability to apply the shared knowledge. Two additional design-principles were employed in the next iterations: (c) provide knowledge representation and organization tools, and (d) employ multiple social-activity structures. The importance of combining several design-principles for designing curricular materials is discussed in terms of Alexander’s design-pattern language and his notion of referencing between design-patterns.  相似文献   

20.
Rudolf   《Applied Soft Computing》2008,8(3):1232-1242
This contribution deals with developments in the history of philosophy, logic, and mathematics during the time before and up to the beginning of fuzzy logic. Even though the term “fuzzy” was introduced by Lotfi A. Zadeh in 1964/1965, it should be noted that older concepts of “vagueness” and “haziness” had previously been discussed in philosophy, logic, mathematics, applied sciences, and medicine. This paper delineates some specific paths through the history of the use of these “loose concepts”. Vagueness was avidly discussed in the fields of logic and philosophy during the first decades of the 20th century—particularly in Vienna, at Cambridge and in Warsaw and Lvov. An interesting sequel to these developments can be seen in the work of the Polish physician and medical philosopher Ludwik Fleck.Haziness and fuzziness were concepts of interest in mathematics and engineering during the second half of the 1900s. The logico-philosophical history presented here covers the work of Bertrand Russell, Max Black, and others. The mathematical–technical history deals with the theories founded by Karl Menger and Lotfi Zadeh. Menger's concepts of probabilistic metrics, hazy sets (ensembles flous) and micro-geometry as well as Zadeh's theory of fuzzy sets paved the way for the establishment of soft computing methods using vague concepts that connote the nonexistence of sharp boundaries.  相似文献   

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