Heart Beat Characterization from Ballistocardiogram Signals using Extended Functions of Multiple Instances

A multiple instance learning (MIL) method, extended Function of Multiple Instances ($e$FUMI), is applied to ballistocardiogram (BCG) signals produced by a hydraulic bed sensor. The goal of this approach is to learn a personalized heartbeat "concept" for an individual. This heartbeat concept is a prototype (or "signature") that characterizes the heartbeat pattern for an individual in ballistocardiogram data. The $e$FUMI method models the problem of learning a heartbeat concept from a BCG signal as a MIL problem. This approach elegantly addresses the uncertainty inherent in a BCG signal e. g., misalignment between training data and ground truth, mis-collection of heartbeat by some transducers, etc. Given a BCG training signal coupled with a ground truth signal (e.g., a pulse finger sensor), training "bags" labeled with only binary labels denoting if a training bag contains a heartbeat signal or not can be generated. Then, using these bags, $e$FUMI learns a personalized concept of heartbeat for a subject as well as several non-heartbeat background concepts. After learning the heartbeat concept, heartbeat detection and heart rate estimation can be applied to test data. Experimental results show that the estimated heartbeat concept found by $e$FUMI is more representative and a more discriminative prototype of the heartbeat signals than those found by comparison MIL methods in the literature.Comment: IEEE EMBC 2016, pp. 1-

Resident Identification using Kinect Depth Image Data and Fuzzy Clustering Techniques

As a part of our passive fall risk assessment research in home environments, we present a method to identify older residents using features extracted from their gait information from a single depth camera. Depth images have been collected continuously for about eight months from several apartments at a senior housing facility. Shape descriptors such as bounding box information and image moments were extracted from silhouettes of the depth images. The features were then clustered using Possibilistic C Means for resident identification. This technology will allow researchers and health professionals to gather more information on the individual residents by filtering out data belonging to non-residents. Gait related information belonging exclusively to the older residents can then be gathered. The data can potentially help detect changes in gait patterns which can be used to analyze fall risk for elderly residents by passively observing them in their home environments

Sit-to-Stand Detection using Fuzzy Clustering Techniques

The ability to rise from a chair is an important parameter to assess the balance deficits of a person. In particular, this can be an indication of risk for falling in elderly persons. Our goal is automated assessment of fall risk using video data. Towards this goal, we present a simple yet effective method of detecting transition, i.e. sit-to-stand and stand-to-sit, from image frames using fuzzy clustering methods on image moments. The technique described in this paper is shown to be robust even in the presence of noise and has been tested on several data sequences using different subjects yielding promising results

A Novel Web-Based Depth Video Rewind Approach toward Fall Preventive Interventions in Hospitals

Falls in the hospital rooms are considered a huge burden on healthcare costs. They can lead to injuries, extended length of stay, and increase in cost for both the patients and the hospital. It can also lead to emotional trauma for the patients and their families [1]. Having Microsoft Kinects installed in the hospital rooms to capture and process every movement in the room, we deployed our previously developed fall-detection system to detect naturally occurring falls, generate a real-time fall alarm and broadcast it to hospital nurses for immediate intervention. These systems also store a processed and reduced version of the 3D depth videos on a central file storage to provide information to the dedicated nursing team for post-fall quality improvement process. The compression technique that helps reducing video size by omitting non-movement frames from it also makes it almost impossible for the hospital staff to find the event that led to a fall alarm. There was a need to visualize fall events and the video contents accordingly. In this paper, we describe a web-application with a handy user interface to easily search among terabytes of depth videos to facilitate the finding and reviewing of the chain of events that lead to a patient fall. We will also discuss the improvements in the new version of the application which reduced the size of transferred videos by converting them to MP4 videos and makes the application platform free. This improvements in speed and compatibility on different browsers, caused more user satisfaction and more frequent use of the web-application

Needing smart home technologies: the perspectives of older adults in continuing care retirement communities

Background At present, the vast majority of older adults reside in the community. Though many older adults live in their own homes, increasing numbers are choosing continuing care retirement communities (CCRCs),which range from independent apartments to assisted living and skilled-nursing facilities. With predictions of a large increase in the segment of the population aged 65 and older, a subsequent increase in demand on CCRCs can be anticipated. With these expectations, researchers have begun exploring the use of smart home information-based technologies in these care facilities to enhance resident quality of life and safety, but little evaluation research exists on older adults' acceptance and use of these technologies. Objective This study investigated the factors that influence the willingness of older adults living in independent and assisted living CCRCs to adopt smart home technology. Subjects and setting Participants (n = 14) were recruited from community-dwelling older adults, aged 65 or older, living in one of two mid-western US CCRC facilities (independent living and assisted living type facilities). Methods This study used a qualitative, descriptive approach, guided by principles of grounded theory research. Data saturation (or when no new themes or issues emerged from group sessions) occurred after four focus groups (n = 11 unique respondents) and was confirmed through additional individual interviews (n = 3). Results The findings from this study indicate that although privacy can be a barrier for older adults' adoption of smart home technology their own perception of their need for the technology can override their privacy concerns. Conclusions Factors influencing self-perception of need for smart home technology, including the influence of primary care providers, are presented. Further exploration of the factors influencing older adults' perceptions of smart home technology need and the development of appropriate interventions is necessary

Anonymized Video Analysis Methods and Systems

Methods and systems for anonymized video analysis are described. In one embodiment, a first silhouette image of a person in a living unit may be accessed. The first silhouette image may be based on a first video signal recorded by a first video camera. A second silhouette image of the person in the living unit may be accessed. The second silhouette image may be of a different view of the person than the first silhouette image. The second silhouette image may be based on a second video signal recorded by a second video camera. A three-dimensional model of the person in voxel space may be generated based on the first silhouette image, the second silhouette image, and viewing conditions of the first video camera and the second video camera. In some embodiments, information on falls, gait parameters, and other movements of the person living unit are determined. Additional methods and systems are disclosed

Cardiovascular sex-differences: insights via physiology-based modeling and potential for noninvasive sensing via ballistocardiography

In this study, anatomical and functional differences between men and women in their cardiovascular systems and how these differences manifest in blood circulation are theoretically and experimentally investigated. A validated mathematical model of the cardiovascular system is used as a virtual laboratory to simulate and compare multiple scenarios where parameters associated with sex differences are varied. Cardiovascular model parameters related with women’s faster heart rate, stronger ventricular contractility, and smaller blood vessels are used as inputs to quantify the impact (i) on the distribution of blood volume through the cardiovascular system, (ii) on the cardiovascular indexes describing the coupling between ventricles and arteries, and (iii) on the ballistocardiogram (BCG) signal. The model-predicted outputs are found to be consistent with published clinical data. Model simulations suggest that the balance between the contractile function of the left ventricle and the load opposed by the arterial circulation attains similar levels in females and males, but is achieved through different combinations of factors. Additionally, we examine the potential of using the BCG waveform, which is directly related to cardiovascular volumes, as a noninvasive method for monitoring cardiovascular function. Our findings provide valuable insights into the underlying mechanisms of cardiovascular sex differences and may help facilitate the development of effective noninvasive cardiovascular monitoring methods for early diagnosis and prevention of cardiovascular disease in both women and men