Virtual Reality (VR) designers and researchers often need to measure emotions and presence as they evolve over time. The experience sampling method (ESM) is a common way to achieve this, however, ESM disrupts the experience and lacks granularity. We propose \tool{}, a new method for measuring subjective emotions and presence in VR, where users watch back their VR experience and retrospectively sketch a plot of their feelings. RetroSketch leaves the VR experience undisturbed and yields highly granular data, including information about salient events and qualitative descriptions of their feelings. We compared RetroSketch and ESM in a large study (n=140) using five different VR experiences over one-hour sessions. Our results show that RetroSketch and ESM measures are highly correlated with each other, as well as physiological measures indicative of emotion. The correlations are robust across different VR experiences and user demographics. They also highlight the impact of ESM on users' experience.

Cryptography is essential to ensure data security in embedded devices that handle sensitive data. SRAM boosts overall performance by temporarily storing cryptographic keys. However, attackers can use side-channel, such as Power Analysis, to exploit power consumption patterns and extract secret keys. Once a key is compromised, encrypted data becomes vulnerable. There are many secure SRAM cell designs available in the literature, but they often degrade other performance parameters. This article presents a novel 10-T SRAM cell design that provides protection against power analysis side-channel attacks (SCA) across all three cell operations, while also maintaining the performance of other key parameters. Monte Carlo simulations were conducted on 1,000 samples each for case when BL = Q and BL ≠ Q during reading, writing, and holding data, using Cadence Virtuoso with a 45-nm technology node at 1V/270°C. Based on these simulations, the mean power difference was evaluated. The proposed P-10T SRAM cell exhibits a 0% mean power difference in all three modes of operation, demonstrating complete resilience to power analysis SCA. The design achieves 84.87% reliability with hold stability, read stability, and write ability values of 429 mV, 242 mV, and 250 mV, respectively. Furthermore, the write power dissipation of P-10T cell is 57.44 μW, which is 1.80 × lower than the power consumed by the conventional 6T cell.

In this article, the authors present an effort to recognize handwritten Gurumukhi place names for use in postal automation. Five feature extraction techniques (zoning, horizontal peak extent, vertical peak extent, diagonal, and centroid) have been analyzed and optimized using Principal Component Analysis (PCA). Four classification methods ( k -Nearest Neighbor ( k -NN), decision tree, random forest, and Convolutional Neural Network (CNN)) have been utilized to classify the handwritten word images. To enhance the recognition results, the authors have employed Bootstrap Aggregation (Bagging) with a majority voting scheme. The authors used a public benchmark dataset of 40,000 handwritten place-name samples in the Punjabi language for their experimental work. The experiments were conducted using a 70:30 partitioning approach, where 70% of the data was utilized for training and the remaining 30% for testing. The system achieved a maximum recognition accuracy of 96.98% by utilizing a combination of zoning, vertical peak extent, and diagonal features, and a minimum Mean Squared Error (MSE) of 0.86% based on a combination of zoning and horizontal peak extent features with a majority voting scheme through ensemble (Bagging) methodology.

Three-dimensional spatial sound field reproduction enables enhanced immersive acoustic experience for a listener. Recreating an arbitrary 3-D spatial sound field using a practically realizable array of loudspeakers is a challenging problem in acoustic signal processing. This paper exploits the underlying characteristics of wavefield propagation to devise a strategy for accurate 3-D sound field reproduction inside a 3-D region of interest with practical array geometries. Specifically, we use the properties of the associated Legendre functions and the spherical Hankel functions, which are part of the solution to the wave equation in spherical coordinates, for loudspeaker placement on a set of multiple circular arrays and provide a technique for spherical harmonic mode-selection to control the reproduced sound field. We also analyze the artifacts of spatial aliasing due to the use of discrete loudspeaker arrays in the region of interest. As an illustration, we design a third-order reproduction system to operate at a frequency of 500 Hz with 18 loudspeakers arranged in a practically realizable configuration.

This paper presents a double sided conical sensor array for common array processing applications. We show that double sided cone arrays are specially suited for extraction of spherical harmonic components of three dimensional spatial wavefields. We use a less known orthogonal relationship of spherical Bessel functions to develop a novel analysis equation for spherical harmonic extraction. As an illustration, we design and simulate a 5th order spherical harmonic decomposition array using 89 microphones to operate over a frequency band of an octave.

Spherical harmonic decomposition of wavefields is not only an active problem in acoustic signal processing but also a useful tool in a plethora of applications such as 3-D beamforming, direction of arrival estimation, and spatial sound recording. This paper presents a novel array structure consisting of a set of parallel circular arrays of sensors to decompose a wavefield into spherical harmonic components. The new structure presented here provides an alternative design to the traditional spherical microphone arrays with increased flexibility on sensor locations. We use the underlying structure of the wave propagation together with the properties of the associated Legendre functions and the spherical Bessel functions to develop a systematic approach to place circular arrays and construct a hybrid array. As an illustration, we design a fifth-order spherical harmonic decomposition array using 57 microphones to operate over a frequency band of an octave and compare it with a spherical array. We use computer simulations to show the performance of the array in a beamforming example.

We present a novel theory and design for constructing microphone arrays to extract spherical harmonic components from sound fields. The proposed non-spherical array structure provides a flexible and alternative design to the traditional spherical microphone arrays with lesser restriction on sensor locations. We use the properties of the associated Legendre functions and the spherical Bessel functions to develop a systematic approach to place circular microphone arrays in three dimensions for hybrid array geometries. As an illustration, we design and simulate a fifth order spherical harmonic decomposition array using 70 microphones to operate over a frequency band of an octave.