This paper presents a fall risk assessment approach based on a fast mobility test, automatically evaluated using a low-cost, scalable system for the recording and analysis of body movement. This ...mobility test has never before been investigated as a sole source of data for fall risk assessment. It can be performed in a very limited space and needs only minimal additional equipment, yet provides large amounts of information, as the presented system can obtain much more data than traditional observation by capturing minute details regarding body movement. The readings are provided wirelessly by one to seven low-cost micro-electro-mechanical inertial measurement units attached to the subject's body segments. Combined with a body model, these allow segment rotations and translations to be computed and for body movements to be recreated in software. The subject can then be automatically classified by an artificial neural network based on selected values in the test, and those with an elevated risk of falls can be identified. Results obtained from a group of 40 subjects of various ages, both healthy volunteers and patients with vestibular system impairment, are presented to demonstrate the combined capabilities of the test and system. Labelling of subjects as fallers and non-fallers was performed using an objective and precise sensory organization test; it is an important novelty as this approach to subject labelling has never before been used in the design and evaluation of fall risk assessment systems. The findings show a true-positive ratio of 85% and true-negative ratio of 63% for classifying subjects as fallers or non-fallers using the introduced fast mobility test, which are noticeably better than those obtained for the long-established Timed Up and Go test.
Abstract This paper presents a decision support system that aims to estimate a patient׳s general condition and detect situations which pose an immediate danger to the patient׳s health or life. The ...use of this system might be especially important in places such as accident and emergency departments or admission wards, where a small medical team has to take care of many patients in various general conditions. Particular stress is laid on cardiovascular and pulmonary conditions, including those leading to sudden cardiac arrest. The proposed system is a stand-alone microprocessor-based device that works in conjunction with a standard vital signs monitor, which provides input signals such as temperature, blood pressure, pulseoxymetry, ECG, and ICG. The signals are preprocessed and analysed by a set of artificial intelligence algorithms, the core of which is based on Bayesian networks. The paper focuses on the construction and evaluation of the Bayesian network, both its structure and numerical specification.
Recent achievements in the field of miniaturization of electronics have led to a significant interest in its application into the protective clothing for firefighters in order to improve their safety ...and health. However, up to now there are not any requirements and standardized test methods enabling confirmation of safety of use and functionality of these systems in work environment. In the paper, an importance of evaluation of such smart wearable system in predicted utility conditions is highlighted. Three variants of the specially developed personal warning systems (PWSs) for integration with either health status or environmental sensors to be used in smart protective clothing for firefighters are presented, i.e., with LCD display, LED diodes and vibrating element. For the purpose of evaluation a new testing methodology was developed. The PWSs were evaluated on a basis of perception of warning signals by firefighters in simulated utility conditions including temperature, light, noise, fog and performed activities. In the case of marching, even 75% of signals generated by PWS with LCD display were not received. Physical activity did not influence on functionality of PWS with vibrating element. For the PWS with LED diodes, the signal was received statistically significantly quicker than in the case of other PWS and the mean value of voice response time was below 3 s.
Atmospheric pressure is the most objective weather factor because regardless of if outdoors or indoors it affects all objects in the same way. The majority of previous studies have used the average ...daily values of atmospheric pressure in a bioclimatic analysis and have found no correlation with blood pressure changes. The main objective of our research was to assess the relationship between atmospheric pressure recorded with a frequency of 1 measurement per minute and the results of 24-h blood pressure monitoring in patients with treated hypertension in different seasons in the moderate climate of the City of Łódź (Poland).
The study group consisted of 1662 patients, divided into 2 equal groups (due to a lower and higher average value of atmospheric pressure). Comparisons between blood pressure values in the 2 groups were performed using the Mann-Whitney U test.
We observed a significant difference in blood pressure recorded during the lower and higher range of atmospheric pressure: on the days of the spring months systolic (p = 0.043) and diastolic (p = 0.005) blood pressure, and at nights of the winter months systolic blood pressure (p = 0.013).
A significant inverse relationship between atmospheric pressure and blood pressure during the spring days and, only for systolic blood pressure, during winter nights was observed. Int J Occup Med Environ Health 2016;29(5):783-792.
The article presents simple modeling and experimental verification of the power required for thermal comfort in electrically heated clothing. The clothing consists of a jumpsuit with embedded heating ...insets, controlled by a dedicated microprocessor system. The user is able to set heating power using a smartphone app. The experiments, conducted in a mobile freezing chamber, aimed at verification of the model of theoretical power (according to ISO 11079) required to maintain thermal comfort in ambient temperatures below 0 °C. Three participants were asked to adjust heating power to reach thermal comfort. The experiment revealed the required power to be only 40–60% of the theoretical one, meaning that the design of the electrically heating clothing relying solely on the theoretical models and standards would lead to oversizing of the heating system power. Further study indicated that the mean skin temperature by itself is not sufficient as an input to the algorithm for automatic maintaining of thermal comfort, even in stationary conditions.
Despite its recent growth in popularity, actively heated clothing still lacks the ability to cope with demanding user scenarios. As many of these deficiencies stem from an absence of automatic ...control, the authors propose a novel approach using a set of sensors embedded in the clothing to provide data about thermal comfort. Available sensors suffer from a lack of accuracy, as for practical reasons, they cannot be attached to the skin, whose temperature is usually used as a comfort indicator. To determine the magnitude of the problem, the authors conducted experiments, and a thermal model was proposed based on experimental findings; the output from the model was compared with the experimental reference data for three different upper body undergarments. The overall accuracy was found to be good: in most cases, the difference between the computed and reference skin temperatures did not exceed 0.5 °C. Furthermore, the model does not rely on unrealistic assumptions regarding the availability of parameters or measurement data. Our findings demonstrate that it is possible to create a thermal model that, when used for input data processing, allows undergarment temperature to be converted to skin temperature, allowing for automatic control of heating insets.
The seamless coexistence of distributed photovoltaics (PV) with the utility network may be maintained by focusing on higher energy autonomy of micro-grids.
This may be approached by seeking any ...opportunities to increase local energy consumption, especially when legal regulations are cutting-down the benefits for energy overproduction.
The microgrids combining PV with electric storage and heat pumps largely fail at satisfying local energy needs autonomously in winter periods and create excessive load of power network. Although the all-electric microgrid is a long term target, any improvements to the existing residential infrastructure with mixed-supply sources are worth revisiting as low-cost steps towards more conscious energy utilization.
The concept of using Domestic Hot Water (DHW) heating to dump locally the excess of PV-energy is affordable method to improve energy autonomy of residential microgrids with minimal interference to their existing configuration and the advantage of no additional energy demand.
The use of PV for DHW heating was studied in various configurations, but in contrast to former works, this paper presents the parametric analysis focusing on increasing the local consumption (goal A), minimizing the interference with utility grid (goal B) and optimal adjustment to net-metering accounting rules (goal C).
The case study is the residential-type micro-grid in climate of Central Europe. The study uses both simulated (energy consumption profiles) and recorded (solar irradiance) data. The simulation is based on microgrid proportions and provides the results beyond reach of single experiments and conclusions applicable to similar cases, regardless the absolute size.
•Parametric analysis of household microgrids with PV and DHW addressing energy autonomy.•Estimation of potential to increase the local utilization of PV-energy with DHWPV.•Guidelines to maximal PV-size assuring unidirectional energy transfer.•Guidelines to optimal over-sizing the PV-system with view of net-metering rules.
Vestibular impairments affect patients' movements and can result in difficulties with daily life activities. The main aim of this study is to answer the question whether a simple and short test such ...as rotation about a vertical axis can be an objective method of assessing balance dysfunction in patients with unilateral vestibular impairments. A 360˚ rotation test was performed using six MediPost devices. The analysis was performed in three ways: (1) the analytical approach based only on data from one sensor; (2) the analytical approach based on data from six sensors; (3) the artificial neural network (ANN) approach based on data from six sensors. For approaches 1 and 2 best results were obtained using maximum angular velocities (MAV) of rotation and rotation duration (RD), while approach 3 used 11 different features. The following sensitivities and specificities were achieved: for approach 1: MAV-80% and 60%, RD-69% and 74%; for approach 2: 61% and 85% and RD-74% and 56%; for approach 3: 88% and 84%. The ANN-based six-sensor approach revealed the best sensitivity and specificity among parameters studied, however one-sensor approach might be a simple screening test used e.g. for rehabilitation purposes.
This study compares HS posturography on inertial sensors (MediPost) with force platform posturography in patients with unilateral vestibular dysfunction. The study group included 38 patients (age ...50.6; SD 11.6) with unilateral vestibular weakness (UV) and 65 healthy volunteers (48.7; SD 11.5). HS tests were performed simultaneously on the force plate and with MediPost sensor attached at L4. Four conditions applied: eyes open/closed, firm/foam. The tests were performed twice, with the head moving at the frequency of 0.3 Hz (HS 0.3) and 0.6 Hz (HS 0.6). Mean sway velocity was significantly lower for MediPost than force plate in 4th condition both in UV and healthy group. For HS 0.3 the differences between devices were marginal; the highest sensitivity (87%) and specificity (95%) were in 4th condition. For HS 0.6 MediPost revealed lower sensitivity than force plate although the surface parameter improved results. MediPost IMU device and force platform posturography revealed a similar ability to differentiate between patients with balance problems in course of vestibular pathology and healthy participants, despite the differences observed between measuring methods. In some tests surface parameter may be more appropriate than sway velocity in improving MediPost sensitivity.
Rescue operations in mountain areas, lasting many hours, pose a mental and physical burden on the rescuer’s body. In addition, they cause thermal discomfort associated with variable energy ...expenditures and the high variability of weather conditions. One of the solutions for improving the comfort of the work of mountain rescuers is clothing with an active heating function. This paper discusses the technology of manufacturing flexible heating inserts with steel thread as a heating element. In order to assess the durability and safety of the applied heating inserts, they were subjected to simulated conditions of use. Multiple washing (25 cycles) and bending (9000 cycles) as well as exposure to artificial acidic sweat did not cause a significant change in the electrical power and resistance of the heating inserts. In order to assess the effectiveness of the inserts, they were tested within a system of clothing fabrics on an “artificial skin model”. Supplying the heating insert with a voltage of 4 V increased the thermal resistance of the fabric system, incorporating the insert by approx. 40%. Due to their high flexibility, durability, and heating efficiency, the developed heating inserts are a major step towards the development of electrical heated clothing.
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