A novel quasi-coherent noise jamming method is proposed against linear frequency modulation (LFM) signal and pulse compression radar. Based on the structure of digital radio frequency memory (DRFM), the jamming signal is acquired by the pseudo-random sequence phase-modulation of sampled radar signal. The characteristic of jamming signal in time domain and frequency domain is analyzed in detail. Results of ambiguity function indicate that the blanket jamming effect along the range direction will be formed when jamming signal passes through the matched filter. By flexible controlling the parameters of interrupted-sampling pulse and pseudo-random sequence, different covering distances and jamming effects will be achieved. When the jamming power is equivalent, this jamming obtains higher process gain compared with non-coherent jamming. The jamming signal enhances the detection threshold and the real target avoids being detected. Simulation results and circuit engineering implementation validate that the jamming signal covers real target effectively.

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Visual perception within a daylit environment changes according to spatiality, sky conditions, time, and the point of observation. This paper focuses on the complex interrelationships among the architectural configuration of skylights, luminance distribution patterns resulting from changing sky conditions, and the perception of spatial depth. This study employed lighting simulation techniques that incorporate physically based rendering and perceptually based tone mapping to generate a pictorial environment. Daylighting conditions were parametrically changed and psychophysical experiments were conducted to measure the perception of distance to visual targets within architectural scenes illuminated by various daylighting conditions. Results reveal that perceived distance to visual targets increases with a decrease in the luminance contrast between the target and background. This paper concludes that variations in luminance within a space influence perceptions of spatial depth, providing the possibility of enriching the experience of architectural scenes through the incorporation of daylighting in design strategies.

A prototype for a wearable signaling device for cyclists is presented. Based on Natural User Interface design concepts, the prototype uses an accelerometer to automatically detect motion changes from turning and braking and to trigger appropriate warning lights in the vest. The system is integrated into a vest made of hard, waterproof cardboard, folded for wearing comfort. Field tests demonstrated that the device detects body movements that anticipate a directional change, and outputs corresponding signals using LED lights without active control from the cyclist. To predict motion changes, a second sensing unit was installed to detect cyclist hand gestures commonly used to inform others of upcoming turns and stops.

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