Acoustic-Field Beamforming for Low-Power Portable Ultrasound.

Portable ultrasound has been extensively used for diagnostic applications in health monitoring, emergency rooms, and ambulances. However, these handheld ultrasound systems may suffer from heat and battery issues attributed to the large power consumption of the transmitter. Additionally, the largest portion of the direct current (DC) power consumption can be attributed to the amplifier in the digital-to-analog converter (DAC) of the transmitter and to the analog-to-digital converter (ADC) of the receiver. Therefore, the number of transmit/receive channels in a portable ultrasound instrument is one of the crucial design factors regarding heat and battery related issues. To address these problems, we propose an acoustic-field beamforming (AFB) technique for low-power portable ultrasound systems with a single receive and five transmit channels. Finally, the simulation, experimental, and in vivo results verified the feasibility of this approach.

Landscape dimension in the built environment: The spatial operative of an integrated micro agriculture unit.

The rapid urbanization creates an increased demand for food supply and security in urban system. The imminent risks stemmed from climate change appeal for a greater effort in an overhaul of the customary practices in the planning and management of the urban systems. Urban centers should accommodate the growing need for green infrastructure and edible landscape; options such as farming alternative has gained interest as a possible solution to the urban-scape and the food production stability for the urban inhabitants. This article presents the systemic approach to building integrated agriculture unit prototype's design thinking and proposed a prototype model allowing the locality and place to be incorporated into the design framework. The research concludes that: (1) in line with human-nature connection and raising its priority level within both design research and design practice should consider the environmental, social, economic and spatial criteria for the design thinking exploration; (2) the design results in a flexible system model of the micro building integrated agriculture unit, allowing the units to fit either indoor or outdoor, as a probable solution suited for the locality and the increasing demand for edible greens; (3) indoor units need further study in integration with the indoor climate control and automation as well as added indoor air purification and sensor functions. (4) Prototype units should be capable of providing locally available edible production and social well-being for the urban system.