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Recently, we developed a comprehensive computer simulated person (CSP) based on computational fluid dynamics (CFD) technique that integrates a computational human body model and respiratory tract model for indoor air quality assessment. Here, we focus on the application of this CSP as an air quality and thermal comfort sensor in an indoor environment, and report the numerical procedure for heating, ventilation, and air conditioning (HVAC) control by using this CSP as the objective function for indoor environmental optimization. We conducted sensitivity analyses in a simple model room with a standing CSP. The analyses of flow, temperature, humidity, and contaminant transfers were coupled with CFD-CSP scheme. Human thermal comfort was evaluated by thermoregulatory analysis and inhalation exposure risk, which was represented by the concentration of contaminants in the inhaled air in the respiratory tract, and was precisely analyzed as a feedback parameter for HVAC control. Compared with the conventional HVAC control method using a point value in a room as the representative value, the HVAC control method integrated with CSP analysis showed potential for precise indoor environmental quality control for local zones around the human body. [ABSTRACT FROM AUTHOR]

This article proposes the design of a four‐element array antenna for the accurate direction of arrival (DOA) estimation of Global Positioning System (GPS) interference signals. The proposed array antenna has four individual antenna elements, and each element consists of a radiating patch on the upper layer and a feeding loop on the lower layer. The patch and loop are intentionally designed in a circular shape to obtain the symmetric current distributions on the radiators. The feeding loop is directly connected by two output ports of an external hybrid chip coupler, and the radiating patch is then electromagnetically coupled by near‐fields of the feeding loop. This feeding mechanism in the proposed structure allows for a more uniform current and H‐field distribution for phase characteristics of the radiation that are close to the ideal isotropic radiators in the azimuth angle. In addition, the high‐dielectric ceramic substrate is adopted to minimize the physical height of the antenna for the phase characteristics of the radiation close to the ideal isotropic radiators in elevation angles. To validate that the phase characteristics are similar to those of an ideal radiator, the DOA estimation performances are observed using a dual‐axis interferometry. The results demonstrate that the proposed four‐element array antenna with phase difference characteristics similar to those of an ideal radiator is suitable for the accurate DOA estimation of GPS interference signals. [ABSTRACT FROM AUTHOR]

ABSTRACT This article proposes the design of microstrip patch antennas to improve low-elevation gain for controlled reception pattern antenna (CRPA) applications. The proposed antenna consists of a main resonant patch and a subpatch that are electromagnetically coupled with each other to operate as a two-element array whose bore-sight direction points toward low-elevation angles. The array factor is then enhanced by inserting a ceramic substrate with a high dielectric constant to maximize the electrical distance between the patches. As a result, the average gain at θ = 75° is enhanced by 1.2 dB, which demonstrates that the proposed antenna is suitable to be used for the individual elements of CRPA arrays with the improved radiation gain at low-elevation angles. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:170-174, 2016 [ABSTRACT FROM AUTHOR]