DESIGN AND IMPLEMENTATION OF A WEARABLE,MULTIPARAMETER PHYSIOLOGICAL MONITORING SYSTEM FOR THE STUDY OF HUMAN HEAT STRESS,COLD STRESS,AND THERMAL COMFORT

This article describes the design and implementation of a wearable, multiparameter physiological monitoring system called the Sensing Belt system, which consists of multiple sensors integrated into fabric that communicates with a physiological data acquisition unit (PDAU) that in turn transmits these data to a remote monitoring center (RMC) for analysis. A number of vital signs can be acquired by the system, including electrocardiography (ECG), respiratory inductance plethysmograph (RIP), posture/activity, multipoint skin temperature (T_SK), and rectal temperature (T_RC). The physiological data can be stored on a MicroSD card or transmitted to the RMC, where specialized analysis will be provided to extract parameters such as heart rate (HR), respiratory rate (RR), respiratory sinus arrhythmia (RSA), and human energy expenditure. The RMC can receive physiological data from up to 16 Sensing Belt users simultaneously. A medical validation test was carried out to compare the accuracy of the physiological data obtained from the Sensing Belt system with data obtained concurrently from traditional, calibrated laboratory physiological monitoring instruments. The results showed that most of the variables measured by the Sensing Belt are within acceptable error limits. The mean temperature on two trials (walking and running) showed significantly higher mean differences than on other trials, but the correlation coefficient (r) remained high (0.985 and 0.989, respectively). This study demonstrates the accuracy of the Sensing Belt system for the monitoring of these physiological parameters and suggests that it could be used to provide a complete human physiological monitoring platform for the study of human heat stress, cold stress, and thermal comfort.     

A GEOMETRICAL APPROACH FOR REDUCTION OF TOOL SHAPE DEGENERATION IN ELECTRIC DISCHARGE MACHINING (EDM)

In this study, the geometric wear characteristics of tool electrodes were obtained for various pulse time, discharge current and machining depth settings in electric discharge machining. Different forms of protrusions were machined on the front surface of the tool to reduce the geometric wear. Significant reductions in original tool geometric wear characteristics (front wear, side wear and edge wear) were obtained with the use of square cross-section protrusions. The dimensions of the square cross-section protrusions were modeled mathematically in terms of machining parameters used in the experiments.     

A PORTABLE FLOW INJECTION ANALYZER FOR THE IN SITU DETERMINATION OF FILTERABLE REACTIVE PHOSPHORUS (FRP) IN FRESHWATER

The development and deployment of a portable flow injection analyzer for continuous, real-time monitoring of filterable reactive phosphorus (FRP) in the Tamar catchment is described. The optimized method can be used for the determination of FRP in freshwater systems (4–150 μg L^?1 P) and is capable of sampling with high temporal resolution (up to 15 samples h^?1). The analyzer, fitted with a pre-filter and an in-line membrane filter (0.45 μm, cellulose acetate), was used in situ (bank-side and shipboard deployment) to provide real-time FRP data and in the laboratory to determine FRP in freshwater samples. The portable FRP analyzer was reproducible (RSD < 5%; n = 3) over the range 4–150 μg L^?1 P and accurate, achieving good agreement with a laboratory based air-segmented continuous flow analyzer reference method for a range of freshwater samples from the Tamar catchment in SW England.