Análisis de las pausas realizadas durante el proceso de producción escrita

En esta comunicación analizaremos el proceso de composición de los alumnos de primer año de Ingeniería a partir de los datos aportados por un programa informático. Para ello, realizamos un experimento que consistió en la escritura, en computadora, de un resumen a partir de la proyección de un video. Participaron del estudio 30 alumnos de primer año de Ingeniería de Petróleos y Civil (Facultad de Ingeniería, Universidad Nacional de Cuyo). Registramos el proceso de producción textual mediante un keylogger. Se tuvo en cuenta la distribución temporal del proceso (duración, tiempo invertido en la escritura y en la realización de pausas, distribución de las pausas y valor de las mismas) y la calidad del texto final (evaluación holista). Los resultados sugieren que los alumnos dedican escaso tiempo a la revisión global final del texto, aún cuando el tiempo de pausa es elevado. Además, activan recursivamente los procesos a lo largo del tiempo de escritura, lo cual se correlaciona con la calidad del producto textual

Análisis de las pausas realizadas durante el proceso de producción escrita

En esta comunicación analizaremos el proceso de composición de los alumnos de primer año de Ingeniería a partir de los datos aportados por un programa informático. Para ello, realizamos un experimento que consistió en la escritura, en computadora, de un resumen a partir de la proyección de un video. Participaron del estudio 30 alumnos de primer año de Ingeniería de Petróleos y Civil (Facultad de Ingeniería, Universidad Nacional de Cuyo). Registramos el proceso de producción textual mediante un keylogger. Se tuvo en cuenta la distribución temporal del proceso (duración, tiempo invertido en la escritura y en la realización de pausas, distribución de las pausas y valor de las mismas) y la calidad del texto final (evaluación holista). Los resultados sugieren que los alumnos dedican escaso tiempo a la revisión global final del texto, aún cuando el tiempo de pausa es elevado. Además, activan recursivamente los procesos a lo largo del tiempo de escritura, lo cual se correlaciona con la calidad del producto textual

Análisis de las pausas realizadas durante el proceso de producción escrita

En esta comunicación analizaremos el proceso de composición de los alumnos de primer año de Ingeniería a partir de los datos aportados por un programa informático. Para ello, realizamos un experimento que consistió en la escritura, en computadora, de un resumen a partir de la proyección de un video. Participaron del estudio 30 alumnos de primer año de Ingeniería de Petróleos y Civil (Facultad de Ingeniería, Universidad Nacional de Cuyo). Registramos el proceso de producción textual mediante un keylogger. Se tuvo en cuenta la distribución temporal del proceso (duración, tiempo invertido en la escritura y en la realización de pausas, distribución de las pausas y valor de las mismas) y la calidad del texto final (evaluación holista). Los resultados sugieren que los alumnos dedican escaso tiempo a la revisión global final del texto, aún cuando el tiempo de pausa es elevado. Además, activan recursivamente los procesos a lo largo del tiempo de escritura, lo cual se correlaciona con la calidad del producto textual

User-representative feature selection for keystroke dynamics

Continuous user authentication with keystroke dynamics uses characters sequences as features. Since users can type characters in any order, it is imperative to find character sequences (n-graphs) that are representative of user typing behavior. The contemporary feature selection approaches do not guarantee selecting frequently-typed features which may cause less accurate statistical user-representation. Furthermore, the selected features do not inherently reflect user typing behavior. We propose four statistical based feature selection techniques that mitigate limitations of existing approaches. The first technique selects the most frequently occurring features. The other three consider different user typing behaviors by selecting: n-graphs that are typed quickly; n-graphs that are typed with consistent time; and n-graphs that have large time variance among users. We use Gunetti’s keystroke dataset and k-means clustering algorithm for our experiments. The results show that among the proposed techniques, the most-frequent feature selection technique can effectively find user representative features. We further substantiate our results by comparing the most-frequent feature selection technique with three existing approaches (popular Italian words, common n-graphs, and least frequent ngraphs). We find that it performs better than the existing approaches after selecting a certain number of most-frequent n-graphs.

Jogging alongside or bumping off? oral history and fiction in dialogue

This paper emerges from my practice-led PhD thesis investigating the ways fiction writers can enter a dialogue with the project of oral history in Australia. In this paper, I survey the current literature in order to identify the status of fiction within the practice of oral history in Australia. I argue that oral historians and fiction writers are, among other things, both concerned with understanding subjectivity. I consider how one of the specific qualities of fiction, that of character, can provide a space to explore subjectivity, and rely on my own writing practice in order to demonstrate how oral history theory can enrich fictive writings. This paper, while positioned in the field of oral history, exists within a wider debate around how the past can legitimately be represented; I argue oral historians and fiction writers can enter a dialogue around shared concerns.

An examination of keystroke dynamics for continuous user authentication

Most current computer systems authorise the user at the start of a session and do not detect whether the current user is still the initial authorised user, a substitute user, or an intruder pretending to be a valid user. Therefore, a system that continuously checks the identity of the user throughout the session is necessary without being intrusive to end-user and/or effectively doing this. Such a system is called a continuous authentication system (CAS). Researchers have applied several approaches for CAS and most of these techniques are based on biometrics. These continuous biometric authentication systems (CBAS) are supplied by user traits and characteristics. One of the main types of biometric is keystroke dynamics which has been widely tried and accepted for providing continuous user authentication. Keystroke dynamics is appealing for many reasons. First, it is less obtrusive, since users will be typing on the computer keyboard anyway. Second, it does not require extra hardware. Finally, keystroke dynamics will be available after the authentication step at the start of the computer session. Currently, there is insufficient research in the CBAS with keystroke dynamics field. To date, most of the existing schemes ignore the continuous authentication scenarios which might affect their practicality in different real world applications. Also, the contemporary CBAS with keystroke dynamics approaches use characters sequences as features that are representative of user typing behavior but their selected features criteria do not guarantee features with strong statistical significance which may cause less accurate statistical user-representation. Furthermore, their selected features do not inherently incorporate user typing behavior. Finally, the existing CBAS that are based on keystroke dynamics are typically dependent on pre-defined user-typing models for continuous authentication. This dependency restricts the systems to authenticate only known users whose typing samples are modelled. This research addresses the previous limitations associated with the existing CBAS schemes by developing a generic model to better identify and understand the characteristics and requirements of each type of CBAS and continuous authentication scenario. Also, the research proposes four statistical-based feature selection techniques that have highest statistical significance and encompasses different user typing behaviors which represent user typing patterns effectively. Finally, the research proposes the user-independent threshold approach that is able to authenticate a user accurately without needing any predefined user typing model a-priori. Also, we enhance the technique to detect the impostor or intruder who may take over during the entire computer session.

Continuous and non-intrusive identity verification in real-time environments based on free-text keystroke dynamics

Internet services are important part of daily activities for most of us. These services come with sophisticated authentication requirements which may not be handled by average Internet users. The management of secure passwords for example creates an extra overhead which is often neglected due to usability reasons. Furthermore, password-based approaches are applicable only for initial logins and do not protect against unlocked workstation attacks. In this paper, we provide a non-intrusive identity verification scheme based on behavior biometrics where keystroke dynamics based-on free-text is used continuously for verifying the identity of a user in real-time. We improved existing keystroke dynamics based verification schemes in four aspects. First, we improve the scalability where we use a constant number of users instead of whole user space to verify the identity of target user. Second, we provide an adaptive user model which enables our solution to take the change of user behavior into consideration in verification decision. Next, we identify a new distance measure which enables us to verify identity of a user with shorter text. Fourth, we decrease the number of false results. Our solution is evaluated on a data set which we have collected from users while they were interacting with their mail-boxes during their daily activities.

Effect of shoes' heel height on the energy cost during jogging

The purpose of this study is to examine the changes of energy cost during a high-heeled continuous jogging.Thirteen healthy female volunteers jointed in this study with heel height of the shoes varied from 1, 4.5 and 7 cm, respectively. Each subjects jogged on the treadmill with K4b2 portable gas analysis system. The results of this study showed that ventilnation, relative oxygen consumption and energy expenditure increased with the increase of heel height and these values shows significantly larger when the heel height reached to 7 cm. Present study suggest that wearing high heel shoes jogging could directly increase energy consumption, causing neuromuscular fatigue.

RTS-3 Task: Mental Jogging

Warm up thinking exercise

User-friendly free-text keystroke dynamics authentication for practical applications

This paper introduces a novel approach for free-text keystroke dynamics authentication which incorporates the use of the keyboard’s key-layout. The method extracts timing features from specific key-pairs. The Euclidean distance is then utilized to find the level of similarity between a user’s profile data and his/her test data. The results obtained from this method are reasonable for free-text authentication while maintaining the maximum level of user relaxation. Moreover, it has been proven in this study that flight time yields better authentication results when compared with dwell time. In particular, the results were obtained with only one training sample for the purpose of practicality and ease of real life application.

Simple classification of walking activities using commodity smart phones

People interact with mobile computing devices everywhere, while sitting, walking, running or even driving. Adapting the interface to suit these contexts is important, thus this paper proposes a simple human activity classification system. Our approach uses a vector magnitude recognition technique to detect and classify when a person is stationary (or not walking), casually walking, or jogging, without any prior training. The user study has confirmed the accuracy.

Physical activity in three regional communities in Queensland

Objective. To describe physical activity participation in three Queensland regional communities. Design. Cross-sectional mail survey of randomly selected residents, stratified by age and sex. Setting. Esk, Mareeba and Mount Isa. Participants. 1219 (58% female) adults, with a mean age 46.7 (SD 14.7) years. Main outcome measures. Proportion of people inactive, meeting Australian activity guidelines (a minimum of 150 minutes/week and 5 sessions/week), and walking a dog daily; time spent walking and cycling for transport; location and type of recreational physical activities. Results. Overall, 18% of respondents were inactive, with the highest proportions among women (22.3%) and older adults in Mount Isa (24.3%). The proportion meeting activity guidelines was 47% with the lowest proportions among women in Mount Isa (40.4%). Although 63% reported owning a dog, only 22% reported walking a dog daily. Few people reported walking or cycling for transport. The most common types of activities were walking, home-based exercise, running/jogging, and swimming, and the most common location was at or near home. Conclusions. Physical activity levels were lower in these regional communities than the state average. The findings indicate a need for physical activity policy and intervention strategies targeting regional and rural areas. This could focus on women and older adults, dog walking, and physical activity opportunities in or near the home.

Identity theft, computers and behavioral biometrics

The increase of online services, such as eBanks, WebMails, in which users are verified by a username and password, is increasingly exploited by Identity Theft procedures. Identity Theft is a fraud, in which someone pretends to be someone else is order to steal money or get other benefits. To overcome the problem of Identity Theft an additional security layer is required. Within the last decades the option of verifying users based on their keystroke dynamics was proposed during login verification. Thus, the imposter has to be able to type in a similar way to the real user in addition to having the username and password. However, verifying users upon login is not enough, since a logged station/mobile is vulnerable for imposters when the user leaves her machine. Thus, verifying users continuously based on their activities is required. Within the last decade there is a growing interest and use of biometrics tools, however, these are often costly and require additional hardware. Behavioral biometrics, in which users are verified, based on their keyboard and mouse activities, present potentially a good solution. In this paper we discuss the problem of Identity Theft and propose behavioral biometrics as a solution. We survey existing studies and list the challenges and propose solutions.

Non-intrusive continuous user behaviour analysis using computerized systems

There are different ways to authenticate humans, which is an essential prerequisite for access control. The authentication process can be subdivided into three categories that rely on something someone i) knows (e.g. password), and/or ii) has (e.g. smart card), and/or iii) is (biometric features). Besides classical attacks on password solutions and the risk that identity-related objects can be stolen, traditional biometric solutions have their own disadvantages such as the requirement of expensive devices, risk of stolen bio-templates etc. Moreover, existing approaches provide the authentication process usually performed only once initially. Non-intrusive and continuous monitoring of user activities emerges as promising solution in hardening authentication process: iii-2) how so. behaves. In recent years various keystroke dynamic behavior-based approaches were published that are able to authenticate humans based on their typing behavior. The majority focuses on so-called static text approaches, where users are requested to type a previously defined text. Relatively few techniques are based on free text approaches that allow a transparent monitoring of user activities and provide continuous verification. Unfortunately only few solutions are deployable in application environments under realistic conditions. Unsolved problems are for instance scalability problems, high response times and error rates. The aim of this work is the development of behavioral-based verification solutions. Our main requirement is to deploy these solutions under realistic conditions within existing environments in order to enable a transparent and free text based continuous verification of active users with low error rates and response times.

Physical activities and sedentary pursuits in African American and Caucasian girls

The purposes of this study were to describe and compare the specific physical activity choices and sedentary pursuits of African American and Caucasian American girls. Participants were 1,124 African American and 1,068 Caucasian American eighth grade students from 31 middle schools. The 3-Day Physical Activity Recall (3DPAR) was used to measure participation in physical activities and sedentary pursuits. The most frequently reported physical activities were walking, basketball, jogging or running, bicycling, and social dancing. Differences between groups were found in 11 physical activities and 3 sedentary pursuits. Participation rates were higher in African American girls (p<.001)for social dancing, basketball, watching television, and church attendance but lower in calisthenics, ballet and other dance, jogging or running, rollerblading, soccer, softball or baseball, using an exercise machine, swimming, and homework. Cultural differences of groups should be considered when planning interventions to promote physical activity.