Deep Room Recognition Using Inaudible Echos

Recent years have seen the increasing need of location awareness by mobile applications. This paper presents a room-level indoor localization approach based on the measured room's echos in response to a two-millisecond single-tone inaudible chirp emitted by a smartphone's loudspeaker. Different from other acoustics-based room recognition systems that record full-spectrum audio for up to ten seconds, our approach records audio in a narrow inaudible band for 0.1 seconds only to preserve the user's privacy. However, the short-time and narrowband audio signal carries limited information about the room's characteristics, presenting challenges to accurate room recognition. This paper applies deep learning to effectively capture the subtle fingerprints in the rooms' acoustic responses. Our extensive experiments show that a two-layer convolutional neural network fed with the spectrogram of the inaudible echos achieve the best performance, compared with alternative designs using other raw data formats and deep models. Based on this result, we design a RoomRecognize cloud service and its mobile client library that enable the mobile application developers to readily implement the room recognition functionality without resorting to any existing infrastructures and add-on hardware. Extensive evaluation shows that RoomRecognize achieves 99.7%, 97.7%, 99%, and 89% accuracy in differentiating 22 and 50 residential/office rooms, 19 spots in a quiet museum, and 15 spots in a crowded museum, respectively. Compared with the state-of-the-art approaches based on support vector machine, RoomRecognize significantly improves the Pareto frontier of recognition accuracy versus robustness against interfering sounds (e.g., ambient music).Comment: 29 page

DNA-templated assembly of metallic nanowires

Nanowires are widely recognized as key elements in the development of futuristic nanoscale devices of nanoelectronics, optoelectronics and nano-electro-mechanic systems. Lithographic fabrication, however, faces increasing difficulties in the realization of continuously miniaturized features. The “Bottom-up” approach is a promising successor to lithography for fabrication of nanostructures. DNA is a natural template for nanowire assembly. The linear polynucleotide chain has a width of 2 nm and a length of 0.34 run per nucleoside subunit. One-dimensional magnetic Co and Ni nanoparticles have been assembled in-situ for the first time by use of single DNA molecules as templates. Target metallic nanowires that are 10–30 nm thick have been grown on DNA templates by catalysis of 2–3 nm Pd nuclei in a three-step electroless plating process. Au microelectrodes have been designed, fabricated, and used to assemble conductive Pd nanowires and DNA-templated Au nanowires. The wires have been characterized with various physical methods. Various methods have been utilized to orient DNA molecules on solid supports and between electrodes. In addition, a novel approach of pre-nucleated growth on designed and synthesized single-stranded DNA templates has been proposed to assemble highly uniform and conductive nanowires by metallic nanoparticle deposition. This research has resulted in the development of novel approaches to fabricate magnetic nanowires, study fundamental aspects of DNA molecule-based nanoassembly, and utilize standard tools of molecular biology in nanotechnology

Radial Shearing Interferometer

Radial shearing interferometer (RSI) is one of the most powerful tools in many domains, especially in optical testing. RSI has compact size and good vibration immunity, which is adaptive to various environments, due to its common-path configuration. Moreover, it is very convenient application because no plane referencing wavefront is needed. The disadvantages of the conventional RSIs are that the distorted wavefront is hard to extract quickly and accurately from one radial shearography due to the phase extract algorithm is complex. Fortunately, the new RSIs can receive benefits from the accuracy of the methods of phase-shifting interferometry, and phase-shifting shearography is more sensitive than simple digital shearography. There are two mainly trend to the RSIs based on phase-shifting technique, i.e. instantaneous phase-shifting and compact size. In this chapter, a development process of RSI will be introduced briefly firstly, and then the some new RSIs based phase-shifting techniques in our work will be described in following parts, including initial RSI by using four-step polarization phase-shifting, modal wavefront reconstruction method for RSI with lateral shear and a new kind of compact RSI based micro-optics technique

Rate-distortion adaptive vector quantization for wavelet imagecoding

We propose a wavelet image coding scheme using rate-distortion adaptive tree-structured residual vector quantization. Wavelet transform coefficient coding is based on the pyramid hierarchy (zero-tree), but rather than determining the zero-tree relation from the coarsest subband to the finest by hard thresholding, the prediction in our scheme is achieved by rate-distortion optimization with adaptive vector quantization on the wavelet coefficients from the finest subband to the coarsest. The proposed method involves only integer operations and can be implemented with very low computational complexity. The preliminary experiments have shown some encouraging results: a PSNR of 30.93 dB is obtained at 0.174 bpp on the test image LENA (512×512

A knowledge-based system for energy-efficient building design

Building designers are constantly facing the problem on how to choose energy conservation options and how to implement them. This is especially true at the preliminary design stage when many important design decisions that significant affectly the energy performance are made. The Model National Energy Code of Canada for Buildings [MNECCB 1995] provides the guidelines for the energy-efficient building design. Knowledge-Based Systems are well suited for the computerization of the Code requirements. By linking to simulation models representing the real world environment, the KBS approach can potentially support most aspects of compliance checking provided in the energy Code. The objective of this research is to develop a systematic and integrated methodology to assemble a computer-based system that will perform as a design assistant. It will help architects and building designers at the preliminary design stage to compare current designs to the MNECCB in areas of the building envelope and lighting

Stochastic Sensing of Nanomolar Inositol 1,4,5-Trisphosphate with an Engineered Pore

AbstractThe introduction of a ring of arginine residues near the constriction in the transmembrane β barrel of the staphylococcal α-hemolysin heptamer yielded a pore that could be almost completely blocked by phosphate anions at pH 7.5. Block did not occur with other oxyanions, including nitrate, sulfate, perchlorate, and citrate. Based on this finding, additional pores were engineered with high affinities for important cell signaling molecules, such as the Ca2+-mobilizing second messenger inositol 1,4,5-trisphosphate (IP3), that contain phosphate groups. One of these engineered pores, PRR-2, provides a ring of fourteen arginines that project into the lumen of the transmembrane barrel. Remarkably, PRR-2 bound IP3 with low nanomolar affinity while failing to bind another second messenger, adenosine 3′, 5′-cyclic monophosphate (cAMP). The engineered α-hemolysin pores may be useful as components of stochastic sensors for cell signaling molecules

Guest Editorial 2020 Custom Integrated Circuits Conference

THIS Special Issue of the IEEE JOURNAL OF SOLIDSTATE CIRCUITS features expanded versions of key articles presented at the 2020 Custom Integrated Circuits Conference (CICC), one of IEEE’s first conferences to go fully virtual due to the corona virus pandemic, from March 22 to March 25, 2020. Originally planned to be held at Hyatt Boston Harbor, Boston, MA, USA, growing concerns related to COVID-19 and the impact on the community’s ability to travel to the conference lead the conference organization to make the tough decision in January 2020 to go for a fully virtual format