Presence Of Human Subjects Research Articles

Analysis of biases in automatic white balance datasets and methods

AbstractAnnotated datasets for automatic white balance (AWB) are used for the evaluation and, when necessary, the training, of AWB methods. Relying on such datasets requires awareness of the potential bias in their content and characteristics: some methods are designed to rely on the presence of particular elements, such as human skin, while other methods learn implicit relationships between image content and light properties from training data. The dependency on these relationships makes it fundamental to understand whether the available datasets are actually representative of common application scenarios, such as the presence of human subjects, the diversity of composition, or the illumination conditions. In this paper we overview the most common datasets for Automatic White Balance, including those for single as well as multiple illuminant estimation, providing a critical analysis on their characteristics. Furthermore, we identify a number of existing methods for single illuminant estimation, as a representative pool of approaches to the problem with various levels of complexity. We investigate how the performance of these correlate to the image content of common datasets.

Using the Phase Change of a Reflected Microwave to Detect a Human Subject Behind a Barrier

In a pulsed radar system, the amplitude and sign of the echo from a particular target will depend on the phase of the echo signal relative to that of the local oscillator signal. If the wavelength of the radar signal is very short, the phase of the echo can change greatly if the target moves even slightly. Based on this physical behavior, the pulsed radar system can serve as a life-detection system to detect a human subject's movements, which include breathing and heartbeat. In this paper, a pulsed microwave life-detection system was developed from a pulsed training radar system to successfully detect the presence of human subjects behind a simulated earthquake rubble wall. The sampled echo signals from the background noise, a dummy, and a female human subject are presented directly in the time domain without being transferred into the frequency domain, differentiating this work from recent works by other authors. Furthermore, we also demonstrate several superiorities of a pulsed system over and above the original continuous-wave approach with the experimental results.

An IC ECG Simulator

Electrocardiogram (ECG) is a graphic recording of electrical activity and can reveal several abnormalities of the coronary system of the heart. Simulating/electronic modelling of the ECG pattern of the human being helps one to learn the types of wave patterns that are generally encountered in an actual situation without the presence of human subject. This paper reports the development of a simple inexpensive ECG simulator using Integrated circuits (ICs). Provision is made to (i) change the rate of the ECG pattern over a good range of beats per minute, (ii) simulate the T wave inversion, (iii) alter the relative positions of each of the constituent waves, and (iv) exhibit certain arrhythmias.

Nitrous Acid Formation in an Experimental Exposure Chamber

Reactive indoor chemistry has seldom been considered in investigations of the health effects of exposure to indoor contaminants although improved understanding may help to reduce exposure misclassification as well as identify previously unknown exposures. Nitrous acid (HONO), formed from the heterogeneous reaction of NO2 with water on indoor surfaces, may be a neglected and important confounder in studies of nitrogen dioxide (NO2) health effects. The understanding of HONO – NO2 relationships is important since conventional measurements of NO2 actually measure a number of nitrogen oxides including HONO. Accordingly, we examined the effects of relative humidity, chamber residence time, the presence of carpeted sufaces and the presence of human subjects on the production of HONO following the injection of NO2 into a chamber. Increasing chamber relative humidity led to greater HONO concentrations at a given NO2 level. At 80% relative humidity, HONO concentrations were 11% of the NO2 concentration. Increased residence time in the chamber increased HONO levels, with a five-fold increase in HONO levels between 20 minute and 120 minute residence times. The presence of wool carpets in the chamber was not found to affect significantly the HONO production rates, although NO2 decay rates were increased. When human subjects were present in the chamber, HONO concentrations decreased by as much as 50% of the levels present under similar conditions with no subjects in the chamber. In light of our results we argue that future investigations of NO2 health effects and indoor air quality must recognize the importance of indoor chemistry, and in particular, the likelihood of elevated concentrations of HONO which will interfere with NO2 measurements and potentially confound the investigation of concentration-effect relationships. Similarly, previous studies demonstrating a relationship between health endpoints and NO2 exposure should be viewed with caution until the presence and importance of other potentially toxic nitrogenous compounds in the exposure environment are evaluated.