“Beating” Fitts’ law: virtual enhancements for pointing facilitation

We survey recent research into new techniques for artificially facilitating pointing at targets in graphical user interfaces. While pointing in the physical world is governed by Fitts’ law and constrained by physical laws, pointing in the virtual world does not necessarily have to abide by the same constraints, opening the possibility for “beating” Fitts’ law with the aid of the computer by artificially reducing the target distance, increasing the target width, or both. The survey suggests that while the techniques developed to date are promising, particularly when applied to the selection of single isolated targets, many of them do not scale well to the common situation in graphical user interfaces where multiple targets are located in close proximity.     

Characterizing computer input with Fitts’ law parameters—the information and non-information aspects of pointing

Throughput (TP), also known as index of performance or bandwidth in Fitts’ law tasks, has been a fundamental metric in quantifying input system performance. The operational definition of TP is varied in the literature. In part thanks to the common interpretations of International Standard ISO 9241-9, the “Ergonomic requirements for office work with visual display terminals—Part 9: Requirements for non-keyboard input devices”, the measurements of throughput have increasingly converged onto the average ratio of index of difficulty (ID) and trial completion time (MT), i.e. TP=ID/MT. In lieu of the complete Fitts’ law regression results that can only be represented by both slope (b) and intercept (a) (or MT=a+b ID), TP has been used as the sole performance characteristic of input devices, which is problematic. We show that TP defined as ID/MT is an ill-defined concept that may change its value with the set of ID values used for the same input device and cannot be generalized beyond specific experimental target distances and sizes. The greater the absolute value of a is, the more variable TP (=ID/MT) is. ID/MT only equals a constant 1/b when a=0. We suggest that future studies should use the complete Fitts’ law regression characterized by (a, b) parameters to characterize an input system. a reflects the non-informational aspect and b the informational aspect of input performance. For convenience, 1/b can be named as throughput which, unlike ID/MT, is conceptually a true constant.     

Speed–accuracy tradeoff in Fitts’ law tasks—on the equivalency of actual and nominal pointing precision

Pointing tasks in human–computer interaction obey certain speed–accuracy tradeoff rules. In general, the more accurate the task to be accomplished, the longer it takes and vice versa. Fitts’ law models the speed–accuracy tradeoff effect in pointing as imposed by the task parameters, through Fitts’ index of difficulty (I_d) based on the ratio of the nominal movement distance and the size of the target. Operating with different speed or accuracy biases, performers may utilize more or less area than the target specifies, introducing another subjective layer of speed–accuracy tradeoff relative to the task specification. A conventional approach to overcome the impact of the subjective layer of speed–accuracy tradeoff is to use the a posteriori “effective” pointing precision W_e in lieu of the nominal target width W. Such an approach has lacked a theoretical or empirical foundation. This study investigates the nature and the relationship of the two layers of speed–accuracy tradeoff by systematically controlling both I_d and the index of target utilization I_u in a set of four experiments. Their results show that the impacts of the two layers of speed–accuracy tradeoff are not fundamentally equivalent. The use of W_e could indeed compensate for the difference in target utilization, but not completely. More logical Fitts’ law parameter estimates can be obtained by the W_e adjustment, although its use also lowers the correlation between pointing time and the index of difficulty. The study also shows the complex interaction effect between I_d and I_u, suggesting that a simple and complete model accommodating both layers of speed–accuracy tradeoff may not exist.     

Validation of a recording system for computer pointing device activity

This study reports on the development of the pointing device activity monitoring software, Mlog, which is used to assess elements of computer use such as pointing device use time. The Mlog monitoring program was written with Virtual C++ and is 1.59 MB in size. It is applicable for computers equipped with computer processing units (CPUs) of 1 GHz or faster, and records pointing device activity at the millisecond level. The accuracy, precision, and reliability of the Mlog monitoring program were tested by comparing Mlog-recorded activity time intervals, for example, the time interval between pressing and releasing the pointing device key, against oscilloscope-recorded pointing device electric signals. For most tested time intervals, the Mlog monitoring program's margin of error for accuracy was within ±0.50%, and it boasted precision error rate of less than 1.00%. Correlation coefficients between the Mlog recordings and the references were all greater than 0.99905, with the highest values observed for dragging actions. For most tested time intervals, the results of the reliability test showed that their intraclass correlation coefficients were higher than 0.95, with few less than 0.90 for those with relatively longer tested time intervals. Linear regression analyses indicated that the pointing device clicking action time intervals recorded by the Mlog monitoring program were very close to the reference values and not affected by CPU speed and memory capacity, computer system loadings of software programs in operation, or types of pointing device key action. In conclusion, the Mlog monitoring program was validated as an accurate tool for monitoring pointing device activity during computer work. Future study is warranted to examine the influences of idle time threshold for electronic activity monitoring, passive computer tasks, and job type on the performance of the program in field studies.

Relevance to industry

The Mlog monitoring program was validated as accurate in measuring pointing device activity during computer work, providing an indirect and supplemental exposure indices for those traditional ergonomic measurements for physical loading assessment.     

The need for a new experimental environment for HCI research into multi-agent,real-time systems

Abstract

Much of the current research in HCI is carried out using experimental environments based on word processors, database search, or other conventional office automation. While this approach meets many needs it lacks the power required for investigating many unconventional situations. Complex multi-agent real-time systems are not typically found in offices and cannot easily be investigated in typical word processing or office automation contexts. The paper refers to four environments where multi-agency exists in a real-time environment: flight systems, plant control, telephone networks, and complex office systems. Consideration is given to the requirements of an alternative experimental environment which could allow HCI research to explore a wider range of issues.     

A comparison of tactile,auditory, and visual feedback in a pointing task using a mouse-type device

A mouse was modified to add tactile feedback via a solenoid-driven pin projecting through a hole in the left mouse button. An experiment is described using a target selection task under five different sensory feedback conditions (‘normal’, auditory, colour, tactile, and combined). No differences were found in overall response times, error rates, or bandwidths; however, significant differences were found in the final positioning times (from the cursor entering the target to selecting the target). For the latter, tactile feedback was the quickest, normal feedback was the slowest. An examination of the spatial distributions in responses showed a peaked, narrow distribution for the normal condition, and a flat, wide distribution for the tactile (and combined) conditions. It is argued that tactile feedback allows subjects to use a wider area of the target and to select targets more quickly once the cursor is inside the target. Design considerations for human-computer interfaces are discussed.     

The Internet’s impact on sexuality: A critical review of 15 years of research

The body of empirical research on Internet sexuality has grown steadily since 1993. The following paper provides an overview of the current state of research in this field in its full thematic breadth, addressing six areas of online sexuality: Pornography, sex shops, sex work, sex education, sex contacts, and sexual subcultures. Key research results are presented concerning Internet sexuality’s forms of manifestation, participant groups, opportunities, and risks. This paper shows that sexually related online activities have become routine in recent years for large segments of the population in the Western world. Internet sexuality also takes somewhat different forms based on the age, gender, and sexual orientation of the individual. Academic studies to date have focused overwhelmingly on the possible negative effects of Internet sexuality. By contrast, little research has been conducted on potential benefits. Consequently, a surprising number of gaps are evident in the scholarship on Internet sexuality.     

新型电驱动活塞式膜式燃气表检定装置设计

研究开发了一种用于民用膜式燃气表检定的电驱动活塞式气体流量标准装置.介绍了电驱动活塞式气体流量标准装置的结构,根据标准装置的结构和膜式燃气表检定规程,推导出膜式燃气表4台联检的数学模型;设计了一种基于LabVIEW平台和PLC的检定系统软硬件;进行活塞式气体流量标准装置的重复性实验,证明该检定装置的重复性优于0.05％...     

Towards the development of a portable device for the monitoring of gaseous toxic industrial chemicals based on a chemical sensor array

The ability of chemical sensor array (CSA) technology to identify multiple gaseous analytes and differentiate between various analyte concentrations has been documented. To date, CSA response was monitored using a flatbed scanner driven by a personal computer. While this system is suitable for use in a laboratory setting it is not suitable for use in the field for environmental monitoring. We describe herein progress made towards the development of a rapid, inexpensive, portable, battery-operated, handheld device based on CSA technology for the detection of toxic industrial compounds (TICs). This prototype successfully differentiates between four TICs at both permissible exposure limit (PEL) and immediately dangerous to life and health (IDLH) concentrations, and three interferent gases, in less than 2 min.     

Electromyographic evaluation of a bed assistive device for abdominal surgery patients in postoperative care

OBJECTIVE: Muscle activity with and without the use of commercially available patient assistive devices during bed rising and lowering was quantified. BACKGROUND: Limited research is available in understanding or evaluating the physical benefits of assistive devices for patient use following major abdominal surgery. METHODS: Twenty healthy participants (9 men, 11 women) took part in a laboratory study to test the effects of device configuration (five levels) and bed elevation angle (0 degree and 30 degrees) on mean and peak upper and lower rectus abdominis and external oblique concentric and eccentric muscle activity. RESULTS: Reduced muscle activity was associated with the use of an assistive device, as compared with manual bed rising (unassisted). Positioning the devices at a higher anchor height and/or increasing the bed elevation angle further reduced muscle activity. Objective and subjective differences between the two assistive devices evaluated in the study were found. CONCLUSION: These results suggest that self-assistive devices may speed recovery because of reduced loads on damaged tissues. APPLICATION: Potential applications of this research include the assessment of other commercially available lift aids or comparisons of self-assistive lift aids with hospital-housed lift aids used to speed recovery rates.     

Revealing the ‘real’ me, searching for the ‘actual’ you: Presentations of self on an internet dating site

This paper considers the presentation of self on an internet dating site. Thirty men and 30 women were interviewed about their online dating experiences. They were asked about how they constructed their profiles and how they viewed other individuals’ profiles. Which types of presentations of self led to more successful offline romantic relationships were also investigated. Additionally, gender differences were examined. In line with previous research on presentation of self online, individuals were quite strategic in their online presentations. However, important differences between initiating a relationship on an internet dating site and other spaces (online and offline) included the type of self disclosed as well as the depth of breadth of information individuals self-disclosed about themselves before any one-on-one conversations took place.     

Control of mixing in a Stokes’ fluid flow

Mixing problems are common in science and engineering, the aim being to combine fluids as quickly and efficiently as possible. We consider the design of a simple controller to promote mixing in a Stokes’ fluid flow. In this paper, a controlled stirring motion is represented by a velocity field consisting of the superposition of a steady base flow and a second field modulated by a saturating, time-dependent control variable. The problem can be formulated as an optimal control one, but the presence of a nonlinearity in the state dynamics and an input constraint make the construction of a feedback law difficult. The size of the problem means that receding horizon schemes, revolving around real-time optimization of even a simplified model, are currently not feasible for fast applications. To address this problem, we exploit theory for the control of bilinear systems to propose a simple, well-performing, explicit feedback law. There are several interesting design issues associated with applying this approach to a fluid mixing application. We demonstrate these by designing a controller for a two-dimensional fluid mixing problem with simple cellular flows and discuss the relevant implementation decisions. The closed-loop forcing fields have many features that are as expected: regions of the flow with large spatial velocity gradients target regular islands of concentration and the input favors velocity fields with contours aligned perpendicular to the scalar field.     

An evaluation tool for research of user behavior in a realistic mobile environment

User behavior is significantly influenced by the surrounding environment. Especially complex and dynamically changing environments (like mobile environment) are represented by a wide variety of extraneous variables, which influence the user behavior in an unpredictable and mostly uncontrolled way. For researchers, it is challenging to measure and analyze the user behavior in such environments. We introduce a complex tool—the IVE tool—which provides a unique way of context visualization and synchronization of measured data of various kinds. Thanks to this tool it is possible to efficiently evaluate data acquired during complex usability tests in a mobile environment. The functionality of this tool is demonstrated on the use case “Navigation of visually impaired users in the building with support of a navigation system called NaviTerier.” During the experiment, we focused on collection and analysis of data that may show user stress and which may influence his/her ability to navigate. We analyzed objective data like Galvanic Skin Response parameter (GSR), Heart Rate Variability parameters (HRV) and audio video recordings and also subjective data like the user’s subjective stress feeling and observation of the user’s behavior.     

A new method for the characterization and evaluation of the optical appearance of reflective TN-LCD's

A method for providing precise data on the angular dependence of brightness and contrast of reflective and transmassive TN-LCDs is described. The basis of the method is a special computer controlled device capable of measuring automatically the intensity of reflected light from a display as a function of the viewing angles. Various evaluation methods, providing sufficient characterization with only a few significant parameters, are presented.     

Towards a Guideline for Design of a Corporate Entrepreneurship Function for Business Development in Medium‐Sized Technology‐Based Companies

The speed with which global high‐technology markets evolve makes companies recognize that an effective innovation process is the best way to guarantee competitiveness. However, when (medium‐sized) companies then wish to set up a corporate entrepreneurship function to enhance business development processes, they can find little material available in literature to assist in such processes. In this article we have described a guideline and some backgrounds for creating a corporate entrepreneurship function to realize business development in a high‐tech context.     

The Greeks had a Word for it: ‘PGP-J’, a Syllogistic Model of the Innovation Process,and a Case Example of Successful Innovation

The processes of individual conceptual discovery and its conversion into a new product or artifact are modelled in the form of a classical syllogism. The processes are represented as cycles of interaction of three mental processes of professionalism, generalism, and philosophy, within a communication domain ‘journalism’ (‘PGP-J’). The system is illustrated with examples including the multiple cycles of innovativeness required within the development of new generations of soil infiltrometers.