Automated classification of human daily activities in ambulatory environment

This paper presents a human daily activity classification approach based on the sensory data collected from a single tri-axial accelerometer worn on waist belt. The classification algorithm was realized to distinguish 6 different activities including standing, jumping, sitting-down, walking, running and falling through three major steps: wavelet transformation, Principle Component Analysis (PCA)-based dimensionality reduction and followed by implementing a radial basis function (RBF) kernel Support Vector Machine (SVM) classifier. Two trials were conducted to evaluate different aspects of the classification scheme. In the first trial, the classifier was trained and evaluated by using a dataset of 420 samples collected from seven subjects by using a k-fold cross-validation method. The parameters σ and c of the RBF kernel were optimized through automatic searching in terms of yielding the highest recognition accuracy and robustness. In the second trial, the generation capability of the classifier was also validated by using the dataset collected from six new subjects. The average classification rates of 95% and 93% are obtained in trials 1 and 2, respectively. The results in trial 2 show the system is also good at classifying activity signals of new subjects. It can be concluded that the collective effects of the usage of single accelerometer sensing, the setting of the accelerometer placement and efficient classifier would make this wearable sensing system more realistic and more comfortable to be implemented for long-term human activity monitoring and classification in ambulatory environment, therefore, more acceptable by users.

Generative models for automatic recognition of human daily activities from a single triaxial accelerometer

In this work, we compare two generative models including Gaussian Mixture Model (GMM) and Hidden Markov Model (HMM) with Support Vector Machine (SVM) classifier for the recognition of six human daily activity (i.e., standing, walking, running, jumping, falling, sitting-down) from a single waist-worn tri-axial accelerometer signals through 4-fold cross-validation and testing on a total of thirteen subjects, achieving an average recognition accuracy of 96.43% and 98.21% in the first experiment and 95.51% and 98.72% in the second, respectively. The results demonstrate that both HMM and GMM are not only able to learn but also capable of generalization while the former outperformed the latter in the recognition of daily activities from a single waist worn tri-axial accelerometer. In addition, these two generative models enable the assessment of human activities based on acceleration signals with varying lengths.

Effect of weighted vest suit worn during daily activities on running speed, jumping power, and agility in young men

Effect of weighted vest suit worn during daily activities on running speed, jumping power, and agility in young men. J Strength Cond Res 26(11): 3030-3035, 2012-Previous weighted vest interventions using exercise in addition to hypergravity have been successful in improving postural balance and power production capacity. The purpose of this study was to investigate if hypergravity alone in daily activities excluding sporting activities is effective in improving neuromuscular performance in young adults. Eight male subjects (age = 32 [SD: 6] years, height = 178 [5] cm, and body mass = 81 [8] kg) wore weighted vests 3 d.wk-1 for 3 weeks during waking hours, excluding sporting activities. Control group comprised 9 male subjects (age = 32 [6] years, height = 179 [5] cm, and body mass = 83 [9] kg). Performance was assessed with countermovement jump (body mass normalized peak power), figure-of-8 running test (running time), and running velocity test at baseline and at the end of the intervention. At baseline, the groups did not differ from each other (multivariate analysis of variance [MANOVA] p = 0.828). A significant group × time interaction (MANOVA F = 5.1, p = 0.015) was observed for performance variables. Analysis of covariance indicated that the intervention improved the figureof- 8 running time (p = 0.016) (22.2 vs. 0.5%), whereas normalized peak power (0.0 vs. 1.6%) and running velocity (1.3 vs. 0.1%) were unaffected (p ≥ 0.095). Wearing weighted vests was effective in slightly improving agility-related performance in young men. Because the effect was small, applying hypergravity only during exercise probably suffices. It appears that a proper volume and intensity of hypergravity could be in the order of 5-10% body weight vest worn during up to 50% of the training sessions for a period of 3-4 weeks.

Developing an instrumental activities of daily living tool as part of the low vision assessment of daily activities protocol

To determine the validity, reliability, and measurement characteristics using factor and Rasch analysis of the Very Low Vision Instrumental Activities of Daily Living (IADL-VLV) in persons with severe vision loss.

Gait termination : a review of experimental methods and the effects of aging and gait pathologies

The study of human gait has expanded and diversified to the extent that it is now possible to identify a substantive literature concerning a variety of gait tasks, such as gait initiation [Halliday SE, Winter DA, Frank JS, Patla AE, Prince F. The initiation of gait in young, elderly, and Parkinson's disease subjects. Gait Posture 1998;8:8–14; Mickelborough J, van der Linden ML, Tallis RC, Ennos AR. Muscle activity during gait initiation in normal elderly people. Gait Posture 2004;19:50–57], stepping over and across obstacles [Patla AE, Prentice SD, Robinson C, Newfold J. Visual control of locomotion: strategies for changing direction and for going over obstacles. J Exp Psych 1991;17:603–34; Chen, HC, Ashton-Miller JA, Alexander NB, Schultz AB. Effect of age and available response time on ability to step over an obstacle. J Gerontol 1994;49:227–33; Sparrow WA, Shinkfield AJ, Chow S, Begg RK. Gait characteristics in stepping over obstacles. Hum Mov Sci 1996;15:605–22; Begg RK, Sparrow WA, Lythgo ND. Time-domain analysis of foot–ground reaction forces in negotiating obstacles. Gait Posture 1998;7:99–109; Patla AE, Rietdyk S. Visual control of limb trajectory over obstacles during locomotion: effect of obstacle height and width. Gait Posture 1993;1:45–60] negotiating raised surfaces such as curbs and stairs [Begg RK, Sparrow WA. Gait characteristics of young and older individuals negotiating a raised surface: implications for the prevention of falls. J Gerontol Med Sci 2000;55A:147–54; Mcfayden BJ, Winter DA. An integrated biomechanical analysis of normal stair ascent and descent. J Biomech 1988;21:733–44]. In addition, increasing research interest in age-related declines in gait that might predispose individuals to falls has engendered a very extensive literature concerning ageing effects on gait. While rapid locomotor adjustments are common in the course of daily activities there has been no previous review of the findings concerning gait adaptations when walking is terminated both rapidly and unexpectedly. The aims of this review were first, to summarise the key research findings and methodological considerations from studies of termination. The second aim was to demonstrate the effects of ageing and gait pathologies on termination with respect to the regulation of step characteristics, lower-limb muscle activation patterns and foot–ground reaction forces.

Motor unit synchronization measured by cross-correlation is not influenced by short-term strength training of a hand muscle

The purpose of the study was to quantify the strength of motor unit synchronization and coherence from pairs of concurrently active motor units before and after short-term (4–8 weeks) strength training of the left first dorsal interosseous (FDI) muscle. Five subjects (age 24.8 ± 4.3 years) performed a training protocol three times/week that consisted of six sets of ten maximal isometric index finger abductions, whereas three subjects (age 27.3 ± 6.7 years) acted as controls. Motor unit activity was recorded from pairs of intramuscular electrodes in the FDI muscle with two separate motor unit recording sessions obtained before and after strength training (trained group) or after 4 weeks of normal daily activities that did not involve training (control group). The training intervention resulted in a 54% (45.2 ± 8.3 to 69.5 ± 13.8 N, P = 0.001) increase in maximal index finger abduction force, whereas there was no change in strength in the control group. A total of 163 motor unit pairs (198 single motor units) were examined in both subject groups, with 52 motor unit pairs obtained from 10 recording sessions before training and 51 motor unit pairs from 10 recording sessions after training. Using the cross-correlation procedure, there was no change in the strength of motor unit synchronization following strength training (common input strength index; 0.71 ± 0.41 to 0.67 ± 0.43 pulses/s). Furthermore, motor unit coherence z scores at low (0–10 Hz; 3.9 ± 0.3 before to 4.4 ± 0.4 after) or high (10–30 Hz; 1.7 ± 0.1 before to 1.9 ± 0.1 after) frequencies were not influenced by strength training. These motor unit data indicate that increases in strength following several weeks of training a hand muscle are not accompanied by changes in motor unit synchronization or coherence, suggesting that these features of correlated motor unit activity are not important in the expression of muscle strength.

Linking human and ecosystem health: the benefits of community involvement in conservation groups

This study explored the health, well-being, and social capital benefits gained by community members who are involved in the management of land for conservation in six rural communities across Victoria. A total of 102 people participated in the study (64 males; 38 females) comprising 51 members of a community-based land management group and 51 controls matched by age and gender. Mixed methods were employed, including the use of an adapted version of Buckner’s (1988) Community Cohesion Scale. The results indicate that involvement in the management of land for conservation may contribute to both the health and well-being of members, and to the social capital of the local community. The members of the land management groups rated their general health higher, reported visiting the doctor less often, felt safer in the local community, and utilized the skills that they have acquired in their lifetime more frequently than the control participants. Male members reported the highest level of general health, and the greatest satisfaction with daily activities. Members also reported a greater sense of belonging to the local community and a greater willingness to work toward improving their community than their control counterparts. Of equal importance is evidence that involvement in voluntary conservation work constitutes a means of building social capital in rural communities which may help reduce some of the negative aspects of rural life.

A security evaluation criteria for baseline security standards

Recent advances in technology and new software applications are steadily transforming human civilization into what is called the Information Society. This is manifested by the new terminology appearing in our daily activities. E-Business, E-Government, E-Learning, E-Contracting, and E-Voting are just a few of the ever-growing list of new terms that are shaping the Information Society. Nonetheless, as "Information" gains more prominence in our society, the task of securing it against all forms of threats becomes a vital and crucial undertaking. Addressing the various security issues confronting our new Information Society, this volume is divided into 13 parts covering the following topics: Information Security Management; Standards of Information Security; Threats and Attacks to Information; Education and Curriculum for Information Security; Social and Ethical Aspects of Information Security; Information Security Services; Multilateral Security; Applications of Information Security; Infrastructure for Information Security Advanced Topics in Security; Legislation for Information Security; Modeling and Analysis for Information Security; Tools for Information Security. Security in the Information Society: Visions and Perspectives comprises the proceedings of the 17th International Conference on Information Security (SEC2002), which was sponsored by the International Federation for Information Processing (IFIP), and jointly organized by IFIP Technical Committee 11 and the Department of Electronics and Electrical Communications of Cairo University. The conference was held in May 2002 in Cairo, Egypt. This volume is essential reading for scholars, researchers, and practitioners interested inkeeping pace with the ever-growing field of Information Security.

Using the sociotechnical approach in global software developments : Is the theory relevant today?

Global software development teams are highly dependent on technology for daily activities and production. Researchers have investigated the areas such as communication and time-zone difficulties when working across global boundaries during the last decade. However, this research explores job satisfaction, efficiency and the quality of working life of people working in a medium sized globally distributed software development organisation. It is assumed that the work structures of organisations of today are influenced by the theories from the past. This paper focus upon the issues that faces an Australian organisation involved in global software development, the research compares and contrasts the feelings of the employees using a Sociotechnical approach. The discussion highlights several problems areas specific to the organisation which will lay the foundation for future research.

Technology education in early childhood setting

Across Victoria, Early Childhood educators are incorporating technology experiences into the daily activities for their children. A small research project, which asked teachers to describe what they did and how they did it, has highlighted some interesting findings. This paper will describe case studies of four pre-school settings and some of the activities undertaken by the children - both as part of the formal program and through incidental play. It will consider these through a socia-cultural framework, noting how teachers used their understandings of play and children's cognitive development, to enhance children's understandings.

Active support, participation and depression

Background
Staff training in Active Support is designed to enable direct support staff to increase the engagement and participation of people with intellectual disabilities in a range of daily activities.

Method
Residents (n = 41) and staff of nine group homes participated. The effectiveness of Active Support was evaluated with a pre-test:post-test design, using a number of standardized assessments and other questionnaires, with group home staff as informants. These assessments were conducted before Active Support training and an average of 6.5 months later.

Results
Following implementation of Active Support residents experienced significant increases in domestic participation and adaptive behaviour. There were significant decreases in internalized challenging behaviour, overall challenging behaviour and depression. There was no significant pre–post change in other forms of challenging behaviour.

Conclusions
Our findings confirm and extend previous Active Support research showing that implementation of Active Support is followed by increased resident participation in activities. The significant improvements in adaptive behaviour, challenging behaviour and depression are of particular interest as the present study is among the first to report such effects. The study’s limitations are discussed.

Television viewing habits and time use in Australian preschool children : an exploratory study

The overall aim in this study was to investigate time use in Australian preschool children, paying close attention to the types of television programs and videos/DVDs they watch. Ninety-two mothers of preschool children completed five activity diaries, for three typical weekdays and two weekend days. On average, children spent around just over 1 hour per weekday watching television and 30 minutes watching videos/DVDs; on weekends they spent on average 1 hour watching television and the same amount of time watching videos/DVDs. On weekdays, children spent more time watching child informative television; on the weekend they spent more time watching child animated television programs. When not watching television, children were mainly engaged in general play or in outdoor play. Child informative television was associated positively with time spent outdoors and in general and pretend play on weekdays (and for general play also on weekend days), whereas overall television viewing was correlated negatively with reading. Our findings suggest that the content of television programs may play a critical role in the relationship between television and other daily activities.

A pilot program of physical activity promotion among clients receiving home and community care

Three Victorian local governments cooperated in a pilot study of physical activity promotion as part of home and community care (HACC) service delivery. Thirty-one people receiving HACC volunteered to participate, including completing the Transtheoretical Stages of Change Exercise Questionnaire and the short-form Stanford Health Assessment Questionnaire (HAQ) just before and at 3 months and 6 months after starting regular self-selected physical activity. Twenty-one participants returned questionnaires at 3 months, and 17 participants returned questionnaires at 6 months. Data were analysed using paired t tests and effect sizes were calculated as mean differences. At 3 months, mean improvements were identified on 6 of the 8 HAQDI (disability index) subscales, and in the overall HAQ-DI score. Improvement in dressing and grooming was preserved at 6 months. At either 3 or 6 months, improvements in dressing and grooming, reach, hygiene, and daily activities, and overall HAQ-DI score exceeded the minimum clinically important difference. No improvements were statistically significant, as is likely in a pilot study with a small sample, however, these results suggest that even very small increases in physical activity may afford clinically meaningful improvements in some areas of physical function required for independent living.

Trends in BMI, diet and lifestyle between 1976 and 2005 in North Sydney

Although the prevalence of overweight and obesity in Australia has increased during the past 30 years, little is known about the dietary and behavioural antecedents of body mass index (BMI). We examined changes in mean BMI, diet, and other lifestyle behaviours between 1976 and 2005 and described the cross-sectional associations between these factors and BMI. A series of biennial biomedical surveys by Sydney Adventist Hospital from 1976 to 2005 allowed examination of BMI trends, while the selection of three surveys enabled detailed examination of likely dietary and lifestyle associations. Subjects included in this study were: 384 men and 338 women in 1976; 160 men and 146 women in 1978; 166 men and 141 women in 1980; 164 men and 142 women in 1982; 177 men and 13 women in 1984; 239 men and 227 women in 1986; 210 men and 225 women in 1988; 165 men and 148 women in 1990; 138 men and 167 women in 1992 and 270 men and 62 women in 2005. Height and weight were measured by hospital staff. Mean BMI increased in the early 1990s. Salt, coffee, cola, alcohol and meat consumption, dieting to lose weight and eating between meals were positively associated with BMI while physical activity, food variety, large breakfasts and consumption of spreads were negatively associated. Food consumption and daily activities have important associations with BMI, though their specific associations differ by sex. 'Affluent' lifestyle patterns appear to contribute to higher BMI, while a more 'prudent' lifestyle seems to protect from such increases.