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Cracking in hydraulic buried engineering can cause localized damage or complete structural failure, potentially resulting in catastrophic project outcomes. Traditional methods for detecting cracks in hydraulic concrete buried engineering are often insufficient in terms of reliability and accuracy. With the development and application of particle-based technology, it has been widely used in the field of crack detection. This research investigates the support pier of the Yingxiuwan Hydropower Plant and the lock pier of the Yuzixi Hydropower Plant. Employing principles from quantum physics, quantum particle non-destructive detection technology is introduced to identify crack locations. A three-dimensional simulation model is constructed and verified accurately through integration with CT scanning techniques. The results demonstrate that particle detection technology effectively detects cracks in hydraulic concrete buried engineering, exhibiting minimal susceptibility to external interference. The particle detection data enable 3D visualization of cracks, accurately reflecting the conditions within embedded concrete components. This method provides a reliable and advanced technical solution for precise crack detection in concrete-embedded engineering and offers critical data for exploring crack propagation mechanisms. [ABSTRACT FROM AUTHOR]

Parkinson's disease is a complex and heterogeneous condition, and there are many gaps in the medical community's scientific and practical understanding of the disease. Closing these gaps relies on objective data about symptoms and signs, collected over long durations. Smartphones contain sensor devices which can be used to remotely capture behavioral signals. From these signals, computational algorithms can distill metrics of symptom severity and progression. This brief review introduces the main concepts of the discipline, addressing the experimental, hardware and software logistics, and computational analysis. The article finishes with an exploration of future prospects for the technology. [ABSTRACT FROM AUTHOR]

• Recoverability criteria of a discrete signal from its m-periodic subsequence is obtained • Predicability is associated with certain arbitrarily small degeneracy of Z-transform for amended subsequneses • Robustness of recover is established The paper investigates recoverability of discrete time signals (sequences) from their subsequences sampled at m -periodic points. It is shown that this recoverability is associated with arbitrarily small spectrum degeneracy of subsequences amended via insertion of dummy elements and bundled into a system. It appears that, for a given m , the signals of a general kind can be approximated by signals with this feature. A recovery algorithm is suggested, and some robustness of this recovery is established. [ABSTRACT FROM AUTHOR]

Radio‐frequency (RF) watermarking is a new technology for physical layer authentication, whose carrier is not the traditional multimedia signals but the digital signals. In the available literature, the watermark detectors are based on the cooperative environment, where the parameters of the watermark signal are known to the receiver. In this Letter, a blind watermark detection scheme with Kolmogorov–Smirnov (K‐S) test is presented. The simulation results show that the proposed scheme is effective. [ABSTRACT FROM AUTHOR]

Certain mechanical and electrical components, such as generators, exhibit degradation phenomena, which may develop slowly over time or suddenly. The current trend in this field of research is to develop malfunction detection indicators from analog signals recorded by operation supervisory control and data acquisition (SCADA), creating behavioral models of the equipment and the development of a series of status indicators. These models and indicators are used to detect malfunctions when operation SCADA are unable to detect an abnormality, thus determining that the component is beginning to degrade when certain normal limits are exceeded. However, the digital signals from operation SCADA have great potential for providing additional information that could be used to detect possible malfunction. Detection must be accompanied by a study of the remaining life of a component so that the remaining useful life of the component before failure can be estimated before losing its functionality. If SCADA can detect a malfunction and determine when the component will break, the operator will have valuable time to intervene prior to failure at an optimum time. This is particularly important in installations with difficult access, such as offshore wind farms. [ABSTRACT FROM AUTHOR]

Continuous conduction mode power factor correction (PFC) without input current measurement is a step forward with respect to previously proposed PFC digital controllers. Inductor volt-second (vsL) measurement in each switching period enables digital estimation of the input current; however, an accurate compensation of the small errors in the measured vsL is required for the estimation to match the actual current. Otherwise, they are accumulated every switching period over the half-line cycle, leading to an appreciable current distortion. A vsL estimation method is proposed, measuring the input (vg) and output voltage (vo). Discontinuous conduction mode (DCM) occurs near input line zero crossings and is detected by measuring the drain-to-source MOSFET voltage vds. Parasitic elements cause a small difference between the estimated voltage across the inductor based on input and output voltage measurements and the actual one, which must be taken into account to estimate the input current in the proposed sensorless PFC digital controller. This paper analyzes the current estimation error caused by errors in the ON-time estimation, voltage measurements, and the parasitic elements. A new digital feedback control with high resolution is also proposed. It cancels the difference between DCM operation time of the real input current, (TDCMg) and the estimated DCM time (TDCMreb). Therefore, the current estimation is calibrated using digital signals during operation in DCM. A fast feedforward coarse time error compensation is carried out with the measured delay of the drive signal, and a fine compensation is achieved with a feedback loop that matches the estimated and real DCM time. The digital controller can be used in universal applications due to the ability of the DCM time feedback loop to autotune based on the operation conditions (power level, input voltage, output voltage...), which improves the operation range in comparison with previous solutions. Experimental results are shown for a 1-kW boost PFC converter over a wide power and voltage range. [ABSTRACT FROM AUTHOR]

Abstract: The ability to actively control the spatial and temporal dynamics of droplets in microfluidic networks can be harnessed for several applications. Achieving such control is nontrivial due to the nonlinear and interactive nature of such systems, where droplets in different branches of the network can affect each other through resistive signalling. In our previous work we have demonstrated the application of a Model Predictive Control (MPC) framework for sort-synchronization in a simple microfluidic loop device, assuming that the final control elements are elastomeric valves. In this paper, we explore the ability of the MPC framework for more intricate control, where the relative drop distances at the exit of a loop are required to conform to desired profiles. We demonstrate that through appropriate MPC objective function choices, a variety of digital signals based on the relative exit distance can be generated. The importance of such control is highlighted. [Copyright &y& Elsevier]

Quantitative analysis of the electroencephalographic signal (EEG) is a useful tool that allows studying the relationship between behavior and nervous system. This signal is susceptible to contamination by artifacts that must be eliminated if a quantitative analysis is required. In this paper the development of a computational program CHECASEN is presented. This program offers a simple way to inspect visually, out of line, a previously digitized electroencephalographic signal and to eliminate the segments contaminated by artifacts or another noise type. It edigraphic.org.mx edigraphic.org.mx permits to make a file where the signal segments selected during the visual inspection as clean or contaminated are enlisted; in addition, it indicates when a segment is possibly contaminated. CHECASEN allows the simultaneous revision until of 32 derivations, runs in ambient Windows in personal computers with at least Pentium processor and 512 Mb in RAM. The output files that it generates are stored in text format, facilitating their later analysis. For this reasons, CHECASEN is easily adaptable to experimental and clinical researches. [ABSTRACT FROM AUTHOR]

BIT BY BIT is an encryption game that is designed to improve students' understanding of natural language processing in computers. Participants encode clear words into binary code using an encryption key and exchange them in the game. BIT BY BIT enables participants who do not understand the concept of binary numbers to perform the process of converting decimal into binary and vice versa. This understanding helps participants to comprehend one of the concepts of computer science (i.e., how computers express natural languages using signals). [ABSTRACT FROM AUTHOR]

The problem of electromagnetic oscillations in a cavity excited by a signal of finite duration is considered. The singly connected cavity surface has arbitrary geometrical form and it is perfectly conducting physically; its volume is filled with a homogeneous lossy medium. The formulation of the problem involves the principle of causality. The problem is solved within the frames of the evolutionary approach to electromagnetics. The electromagnetic field is presented as an eigenmodal expansion with time dependent modal amplitudes. The amplitudes satisfy a system of evolution (i.e., with tithe derivative) ordinary differential equations, which are derived and studied. Explicit solutions are obtained satisfying the principle of causality automatically. Numerical examples for the cavity oscillations excited by the Walsh function signals are exhibited, some resonances of the digital signals are revealed. [ABSTRACT FROM AUTHOR]

What signals quality for digital startups seeking access to external finance? Analyzing a unique dataset from India, we investigate the impact of traditional quality signals (e.g., the founders' years of experience, prior industry experience); networking signals (e.g., degrees from elite educational institutes, the breadth of an entrepreneurial team); and digital signals (e.g., the social media presence of the startup on multiple social media sites) on the access to venture capital financing. We find that while networking and digital signals positively impact access to financing, traditional human capital signals do not have any significant impact on the process. • Our study provides support for the changing importance of signals over time. • Traditional human capital factors may not necessarily serve as quality signals. • Digital signals may serve better quality signals to access financing for startups. • We make important contribution to the signaling literature for emerging economies. [ABSTRACT FROM AUTHOR]