User Recognition Based on Human Body Impulse Response: A Feasibility Study

Human recognition technologies for security systems require high reliability and easy accessibility in the advent of the internet of things (IoT). While several biometric approaches have been studied for user recognition, there are demands for more convenient techniques suitable for the IoT devices. Recently, electrical frequency responses of the human body have been unveiled as one of promising biometric signals, but the pilot studies are inconclusive about the characteristics of human body as a transmission medium for electric signals. This paper provides a multi-domain analysis of human body impulse responses (HBIR) measured at the receiver when customized impulse signals are passed through the human body. We analyzed the impulse responses in the time, frequency, and wavelet domains and extracted representative feature vectors using a proposed accumulated difference metric in each domain. The classification performance was tested using the k-nearest neighbors (KNN) algorithm and the support vector machine (SVM) algorithm on 10-day data acquired from five subjects. The average classification accuracies of the simple classifier KNN for the time, frequency, and wavelet features reached 92.99%, 77.01%, and 94.55%, respectively. In addition, the kernel-based SVM slightly improved the accuracies of three features by 0.58%, 2.34%, and 0.42%, respectively. The result shows potential of the proposed approach for user recognition based on HBIR

Mitochondrial dysfunction triggers actin polymerization necessary for rapid glycolytic activation

Publisher Copyright: © 2022 Chakrabarti et al.Mitochondrial damage represents a dramatic change in cellular homeostasis. One rapid response is perimitochondrial actin polymerization, termed acute damage-induced actin (ADA). The consequences of ADA are not understood. In this study, we show evidence suggesting that ADA is linked to rapid glycolytic activation upon mitochondrial damage in multiple cells, including mouse embryonic fibroblasts and effector CD8+ T lymphocytes. ADA-inducing treatments include CCCP, antimycin, rotenone, oligomycin, and hypoxia. The Arp2/3 complex inhibitor CK666 or the mitochondrial sodium–calcium exchanger (NCLX) inhibitor CGP37157 inhibits both ADA and the glycolytic increase within 5 min, supporting ADA’s role in glycolytic stimulation. Two situations causing chronic reductions in mitochondrial ATP production, mitochondrial DNA depletion and mutation to the NDUFS4 subunit of complex 1 of the electron transport chain, cause persistent perimitochondrial actin filaments similar to ADA. CK666 treatment causes rapid mitochondrial actin loss and a drop in ATP in NDUFS4 knock-out cells. We propose that ADA is necessary for rapid glycolytic activation upon mitochondrial impairment, to re-establish ATP production.Peer reviewe

Proteome-wide characterization of signalling interactions in the hippocampal CA4/DG subfield of patients with Alzheimer’s disease

Alzheimer's disease (AD) is the most common form of dementia; however, mechanisms and biomarkers remain unclear. Here, we examined hippocampal CA4 and dentate gyrus subfields, which are less studied in the context of AD pathology, in post-mortem AD and control tissue to identify possible biomarkers. We performed mass spectrometry-based proteomic analysis combined with label-free quantification for identification of differentially expressed proteins. We identified 4,328 proteins, of which 113 showed more than 2-fold higher or lower expression in AD hippocampi than in control tissues. Five proteins were identified as putative AD biomarkers (MDH2, PCLO, TRRAP, YWHAZ, and MUC19 isoform 5) and were cross-validated by immunoblotting, selected reaction monitoring, and MALDI imaging. We also used a bioinformatics approach to examine upstream signalling interactions of the 113 regulated proteins. Five upstream signalling (IGF1, BDNF, ZAP70, MYC, and cyclosporin A) factors showed novel interactions in AD hippocampi. Taken together, these results demonstrate a novel platform that may provide new strategies for the early detection of AD and thus its diagnosis

Direct Observation of Defects and Increased Ion Permeability of a Membrane Induced by Structurally Disordered Cu/Zn-Superoxide Dismutase Aggregates

Interactions between protein aggregates and a cellular membrane have been strongly implicated in many protein conformational diseases. However, such interactions for the case of Cu/Zn superoxide dismutase (SOD1) protein, which is related to fatal neurodegenerative disorder amyotrophic lateral sclerosis (ALS), have not been explored yet. For the first time, we report the direct observation of defect formation and increased ion permeability of a membrane induced by SOD1 aggregates using a supported lipid bilayer and membrane patches of human embryonic kidney cells as model membranes. We observed that aggregated SOD1 significantly induced the formation of defects within lipid membranes and caused the perturbation of membrane permeability, based on surface plasmon resonance spectroscopy, atomic force microscopy and electrophysiology. In the case of apo SOD1 with an unfolded structure, we found that it bound to the lipid membrane surface and slightly perturbed membrane permeability, compared to other folded proteins (holo SOD1 and bovine serum albumin). The changes in membrane integrity and permeability were found to be strongly dependent on the type of proteins and the amount of aggregates present. We expect that the findings presented herein will advance our understanding of the pathway by which structurally disordered SOD1 aggregates exert toxicity in vivo

Adaptive Acoustic Beamforming and Speech Processing Front-end

Noise is a primary factor limiting the accuracy of automatic speech recognition (ASR). Multi-channel beamforming is essential to suppress noise and enhance the desired speech signal. This thesis presents three fully-integrated ASR frontend systems that suppress noise and increase speech recognition accuracy in a noisy environment. The thesis focuses on the ASR frontend, which includes ADCs, adaptive beamforming, and feature extraction. We take advantage of the bitstream output of sigma-delta modulation (SDM) for fine delay resolution. We present three different beamformer prototypes with power/area-efficient hardware implementations. The first system (Chapter 2) makes use of the synergy between data conversion and signal processing. It combines eight-channel delay-and-sum beamforming with frequency-selective beamforming and a 60-feature Mel frequency extractor to enable constant-directivity beamforming. The system improves the angular resolution of beamsteering by directly processing the raw bitstream outputs of third-order SDMs. The 40nm CMOS prototype has an active area of 1.1mm2 and consumes 4mW. It improves the keyword spotting (KWS) accuracy from 73% to 93% using a DNN trained with noiseless speech. The system in Chapter 3 combines a four-channel adaptive beamformer and a 40 feature Mel frequency extractor. The prototype processes the bitstream output of a 3rd order delta-sigma modulator output for accurate steering. For a given steering vector, the beamformer adaptively places a null in the noise direction by using a robust generalized sidelobe canceller (RGSC). Hardware sharing and DSP clock optimization reduce area and power consumption. It is fabricated in 40nm CMOS, occupies an active area of 0.89mm2, and consumes 0.65mW. The prototype beamformer improves speech recognition accuracy in noisy conditions from 64% to 90% using DNN trained with noisy speech. Finally, the third system in Chapter 4 presents a four-channel greedy adaptive beamformer and a multi-mode ADC. The proposed system adapts beamforming and ADC performance to optimize power consumption depending on the target signal and noise. The multi-mode ADC can operate as a continuous-time noise-shaping SAR ADC (CT NSSAR) (80dBA/12μW), NSSAR ADC (65dBA/5.8μW), or as a SAR ADC (40dBA/1.5μW). The direct output of CTNSSAR enables the newly proposed greedy adaptive beamformer, which can track the direction of arrival (DOA) of the target signal, reduce signal distortion and power consumption. The 40nm CMOS prototype occupies 0.93mm2 and consumes 157μW in high-performance mode. It improves KWS accuracy from 54% to 83% in the presence of spoken-word interference using a DNN trained with noisy speech.PhDElectrical and Computer EngineeringUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/171342/1/twkang_1.pd

Development of a Conceptual Mapping Standard to Link Building and Geospatial Information

This study introduces the BIM (building information modeling)-GIS (geographic information system) conceptual mapping (B2GM) standard ISO N19166 and proposes a mapping mechanism. In addition, the major issues concerning BIM-GIS integration, and the considerations that it requires, are discussed. The B2GM is currently being standardized by the spatial-information international standardization organization TC211. Previous studies on BIM-GIS integration seem to focus on the integration of different types of model schemas and on the implementation of service interfaces. B2GM concerns the clear definition of the conditions and methods for mapping the object information required from the user’s use-case viewpoint for city-scale mapping. The benefits of the B2GM approach are that the user is able directly control the BIM-GIS linkage and integration process in order to acquire the necessary objection information. This can reveal cases of possibly unclear BIM-GIS integration outside the black box in an explicit and standard way, so that the user can distinctively predict the final output obtainable from the BIM-GIS integration. This study examined B2GM in terms of its development background, components, and several utilization examples, as well as the levels and considerations of the integration of different BIM-GIS models

BIM-Based Human Machine Interface (HMI) Framework for Energy Management

This study proposes a Building Information Modeling (BIM)-based Human Machine Interface (HMI) framework for intuitive space-based energy management. The BIM-based HMI supports building managers with a method of linking data between BIM and Building Energy Management System (BEMS), which are heterogeneous systems, and provides space-based real-time energy monitoring. This study also proposes a BIM and BEMS data linking framework for systematic BIM-based HMI development. Towards this end, the BIM-based HMI framework was defined after deriving the considerations and requirements necessary for linking the energy control point and BIM through a questionnaire designed by practitioners. Through case analysis, the authors implemented BIM-based HMI and analyzed its effects. The results of the analysis confirmed the positive effects (3.9/5.0) on the connectivity of BIM-based HMI, the benefits (4.3/5.0) for real-time data monitoring, the system function expandability, and the BIM-based spatial intuitiveness

Feature Template–Based Parametric Swept Geometry Generation from Point Cloud Data: Pipeline Design in Building Systems

Reverse engineering has been used in construction, including residential and commercial buildings and heavy civil constructions, to help integrity access complex or combined damages. However, the previous reverse-engineering process was an inefficient timely manner approach, which was simple to measure the dimensions by the equipment, recorded and modeled by personnel who has engineering knowledge. For this reason, this research study focuses on developing reverse-engineering methods to support the previous reverse-engineering process, which is the parametric swept geometry definition and generation with a predefined feature template (FT) from point cloud data (PCD). PCD were recently obtained and used from the scanned images for facility management purposes. However, the geometry modeling for management in PCD required a lot of effort and time consumption. This research study focuses on the pipelines in mechanical, electrical, and plumbing (MEP) systems as a case study. The swept geometry, which includes ducts, cable trays, pipes, and H-beams, was modeled considering standardized dimensions and constraints in MEP systems in building construction. This study also finds how to generate the parametric swept geometry from PCD based on the predefined FT and provide engineers/designers with flexible reverse-engineering capabilities

Review of capacitive coupling human body communications based on digital transmission

Human body communications (HBC) have been studied as an enabling technology to meet the recently increased demands for low-power and high-simplicity in wireless body area networks for wearable-device applications. Previous works on HBC focused mainly on channel modeling with a measurement method, signal transmission scheme, and transceiver implementation. In particular, the digital transmission, invented as a customized approach for the human body channel, has contributed to develope low-complexity HBC systems. This paper addresses on-going research on capacitive coupling HBC based on digital transmission by exploring recent literature