Delay Measurements Research Articles

Differential outcomes of high-fat diet on age-related rescaling of cochlear frequency place coding.

Auditory frequency coding is place-specific, which depends on the mechanical coupling of the basilar membrane-outer hair cell (OHC)-tectorial membrane network. Prestin-based OHC electromotility improves cochlear frequency selectivity and sensitivity. Cochlear amplification determines the frequency coding wherein discrete sound frequencies find a 'best' place along the cochlear length. Loss of OHC is the leading cause of age-related hearing loss (ARHL) and is the most common cause of sensorineural hearing loss and compromised speech perception. Lipid interaction with Prestin impacts OHC function. It has been established that high-fat diet (HFD) is associated with ARHL. To determine whether genetic background and metabolism preserve cochlear frequency place coding, we examined the effect of HFD in C57BL/6J (B6) and CBA/CaJ (CBA) on ARHL.We found a significant rescuing effect on ARHL in aged B6 HFD cohort. Prestin levels and cell sizes were better maintained in the experimental B6-HFD group. We also found that distortion product otoacoustic emission (DPOAE) group delay measurement was preserved, which suggested stable frequency place coding. In contrast, the response to HFD in the CBA cohort was modest with no appreciable benefit to hearing threshold. Notably, group delay was shortened with age along with the control. In addition, the frequency dependent OHC nonlinear capacitance gradient was most pronounced at young age but decreased with age. Cochlear RNA-seq analysis revealed differential TRPV1 expression and lipid homeostasis. Activation of TRPV1 and downregulation of arachidonic acid led to downregulation of inflammatory response in B6 HFD, which protects the cochlea from ARHL. The genetic background and metabolic state-derived changes in OHC morphology and function collectively contribute to a redefined cochlear frequency place coding and improved age-related pitch perception.

Initial Margin Requirements and Market Efficiency

AbstractWe examine the association between margin requirements and the market’s efficiency in incorporating firm-specific and market-level public news. Combining the Fed’s 22 changes in margin requirements with a hand-collected sample of earnings announcements between 1934 and 1975, we show that higher margin requirements induce greater delay in incorporating earnings information into prices. We draw similar conclusions when we analyze the Hou and Moskowitz (2005) price delay measure, as well as indirect measures of leverage constraints over recent years. Further tests suggest that, despite the Fed’s expressed intent to curtail excess speculation, higher margin requirements restrict trading by arbitrageurs more than noise traders.

Kalman Filter Based Pseudo-Code Ranging and Carrier Phase Measurement for Fiber Optical Time Transfer Method

In the optical fiber time transfer system, fiber optic time transfer is limited by the pulse signal time delay measurement precision, and cannot benefit from a higher precision of the carrier phase information. Its transfer precision compared to the frequency transfer exists in a larger gap transfer. This paper proposes a time delay measurement method based on carrier phase and pseudo-code ranging for optical time transfer. The time signal is modulated with pseudo-random code and carrier at the transmitter, and the time delay is measured at the receiver by the methods of pseudo-code ranging and carrier phase measurement. The time transfer is achieved by eliminating the transmission link delay through a two-way method. The first-order difference value of the carrier phase measurement and the pseudo-code ranging measurement are used as the observation quantities, and they are fused through a Kalman filtering method to finally obtain the high-precision time difference measurement. We validate the theory on the common-clock experimental platform over a 50 km fiber link, The time transfer stabilities of the systems are 5.2254×10−14/s and 2.146×10−16/104 s (modified Allan deviation), 3.0169×10−14/s and 1.2392×10−12/104 s (time deviation). The standard deviation of the time transfer system after fusion can reach 2.4255 ps.

Insights into the Fusion Correction Algorithm for On-Board NOx Sensor Measurement Results from Heavy-Duty Diesel Vehicles

Over the last decade, Nitrogen Oxide (NOx) emissions have garnered significantly greater attention due to the worldwide emphasis on sustainable development strategies. In response to the issues of dynamic measurement delay and low measurement accuracy in the NOx sensors of heavy-duty diesel vehicles, a novel Multilayer Perceptron (MLP)–Random Forest Regression (RFR) fusion algorithm was proposed and explored in this research. The algorithm could help perform post-correction processing on the measurement results of diesel vehicle NOx sensors, thereby improving the reliability of the measurement results. The results show that the measurement errors of the On-board Nitrogen oxide Sensors (OBNS) were reduced significantly after the MLP-RFR fusion algorithm was corrected. Within the concentration range of 0–90 ppm, the absolute measurement error of the sensor was reduced to ±4 ppm, representing a decrease of 73.3%. Within the 91–1000 ppm concentration range, the relative measurement error was optimised from 35% to 17%, providing a reliable solution to improve the accuracy of the OBNS. The findings of this research make a substantial contribution towards enhancing the efficacy of the remote monitoring of emissions from heavy-duty diesel vehicles.

A robust lp‐norm localization of moving targets in distributed multiple‐input multiple‐output radar with measurement outliers

AbstractThe Gaussian noise model and estimators based on least squares (LS) are widely used in target localisation with distributed multiple‐input multiple‐output (MIMO) radar because of their computational efficiency. However, the accuracy of existing LS‐based target localisation algorithms deteriorates sharply in the presence of outliers in the measurements. Thus, a robust solution is developed based on the ‐norm minimisation criterion and iteratively reweighted least squares (IRLS) for locating a moving target with impulse noise using the angle of arrival (AOA), time delay (TD), and Doppler shift (DS) measurements. First, the AOA, TD, and DS measurement noise models are developed based on the α‐stable distribution. Then, the localisation problem is transformed into an ‐norm minimisation problem by linearising the AOA, TD, and DS measurement equations. Finally, the ‐norm minimisation problem is solved using an IRLS method to obtain the target position and estimate the velocity. Moreover, the optimum of the norm order (p) and the Cramér–Rao lower bound for the target position and velocity estimation are derived under α‐stable distributed measurement noise. The simulation results demonstrate that the developed algorithm offers higher accurascy and robustness than the existing ones in the presence of measurement outliers.

Experimental measurements of ultra-lean hydrogen ignition delays using a rapid compression machine under internal combustion engine conditions

In order to mitigate greenhouse gas and pollutant emissions from the transportation sector, the use of green e-fuels is planned. Hydrogen spark ignition engines (H2ICEs) are one of the most important technologies for reducing dependence on fossil fuels. However, these combustion engines are prone to some abnormal combustion phenomena, such as knocking, and require further investigation to get a better understanding of hydrogen combustion properties. This study used a rapid compression machine to present experimental ignition delay measurements of ultra-lean hydrogen/air mixtures under internal combustion engine conditions. The fuel–air ratio ranged from 0.2 to 0.5, the compression temperature varied from 900 to 1030 K, and the compression pressure ranged from 20 to 60 bar. A comparison with often-used and up-to-date hydrogen kinetic mechanisms was performed. The experimental results were consistent and showed an overall good agreement with numerical simulations. The impact of 2 HO2 ⇌ 2 OH + O2 addition on recent kinetic mechanisms was also investigated and presented an average decrease of 20% in ignition delay. Finally, new third-body efficiencies of H2O were evaluated and showed no impact on prediction. The aim of this approach was to provide new experimental data for kinetic mechanism validation and optimization.

Effect of test conditions on the efficiency and hysteresis of Sn-Pb mixed perovskite solar cells

With the continuous improvement of the efficiency of perovskite solar cells (PSCs), the possible pollution of lead to the environment has become a significant. The appearance of tin–lead mixed PSCs reduces its toxicity. Still, tin-based perovskite materials are easy to oxidize and decompose in the air, which poses a challenge to evaluate its photoelectric performance in the test process correctly. Our work compared and analyzed the photoelectric performance of tin–lead mixed PSCs from the test environment and setting parameters. We discussed the effects of temperature, humidity, measurement delay time, measurement step, and bias voltage on the efficiency and hysteresis of tin–lead mixed PSCs. We summarized the standard test conditions applicable to tin–lead mixed PSCs. The reference of this test method will help to get accurate test results of tin–lead mixed PSCs and promote its further development.

COVID-19-related financial scarcity is associated with greater delay discounting but not probability discounting

Prior studies suggest that scarcity increases delay discounting (devaluation of delayed outcomes) and disturbs other decision-making processes. Evidence on the effect of COVID-19 on delay discounting is mixed. Also, no study has examined the effect of COVID-19-related scarcity on probability discounting (devaluation of probabilistic outcomes). The goal of the study was to examine cross-sectional associations between financial impact during the COVID-19 pandemic, delay discounting, and probability discounting. During April 2020, 1012 participants with low income were recruited on Amazon Mechanical Turk and completed measures of delay and probability discounting, perceived COVID-19-related financial impacts, and food security. Regression analyses indicate that compared to those with no COVID-19-related financial impacts, those with severe COVID-19-related financial impacts had greater delay discounting of money and greater delay discounting of a grocery gift card. Also, greater food insecurity in the past month was associated with greater delay discounting of a grocery gift card but not delay discounting of money. Perceived COVID-19 related financial impact was not associated with probability discounting. Combined with laboratory experiments, this study provides additional support for the idea that feelings of scarcity may increase delay discounting. However, as this study was observational, no assumptions of causality should be made about the specific effect of COVID-19 on delay discounting.

Hundred-femtosecond-level concise optical time delay measurement system based on linear optical sampling

Fiber-delay measurement is one of the key fundamental technologies in numerous fields. Here, we propose and experimentally demonstrate a high-precision and concise optical time delay measurement system based on the technique of linear optical sampling, reaching the precision better than 100 fs under averaging. The use of only two optical frequency combs without locking the carrier-envelope-offset frequency greatly simplifies the structure of the time-delay measurement system. We also experimentally investigate the current limitations on the precision of the system. The timing jitter noises of two sources are mainly non-common mode and are both restricted to the frequency sources. Our results indicate that the proposed device can measure fiber length fluctuations below 10 µm, paving the way for further analyses of the external disturbances on the fiber link.

Host group degeneracy in gravitational lensing time delay determination of H 0

Abstract Massive elliptical galaxies, that serve as lenses in gravitational lensing time delay measurements of the Hubble parameter H 0, often reside in a host group. We consider degeneracies in the modeling of the group halo. When the group effect on imaging can be summarized by its flexion (the next order term beyond shear in the tidal expansion), the posterior likelihood map can develop disjoint local minima, associated with an approximate discrete symmetry of a dominant flexion term. Monte-Carlo Markov Chain (MCMC) algorithms that are not designed to explore a rich posterior landscape can miss some of the minima, introducing systematic bias. We study mock data and demonstrate that the bias in H 0 can exceed 10%, and pulls the inference value of H 0 above its truth value, for a reason that can be traced to the structure of a mismodeled flexion term. MCMC algorithms that are designed to cope with a rich posterior landscape can uncover the structure. If the group is X-ray bright enough, X-ray data may also help to resolve the degeneracy, by pinpointing the group's center of mass. Finally, we show that some implementations in the literature used an inaccurate kinematical prior, mis-modeling the group velocity dispersion by as much as 20%.

Strong lensed QSOs with variability detectable by LSST: How many are there?

ABSTRACT Strong lensed quasi-stellar objects (QSOs) are valuable probes of the Universe in numerous aspects. Two of these applications, reverberation mapping and measuring time delays for determining cosmological parameters, require the source QSOs to be variable with sufficient amplitude. In this paper, we forecast the number of strong lensed QSOs with sufficient variability to be detected by the Vera C. Rubin Telescope Legacy Survey of Space and Time (LSST). The damped random walk model is employed to model the variability amplitude of lensed QSOs taken from a mock catalogue by Oguri & Marshall (2010). We expect 30–40 per cent of the mock lensed QSO sample, which corresponds to ∼1000, to exhibit variability detectable with LSST. A smaller subsample of 250 lensed QSOs will show larger variability of >0.15 mag for bright lensed images with i < 21 mag, allowing for monitoring with smaller telescopes. We discuss systematic uncertainties in the prediction by considering alternative prescriptions for variability and mock lens catalogue with respect to our fiducial model. Our study shows that a large-scale survey of lensed QSOs can be conducted for reverberation mapping and time delay measurements following up on LSST.

Іnformation modeling of the processes of sensory perception of information and user identification

The article proposes a systematic approach to the analysis of psychological perception of information at the level of human intuitive perception. The most successful, according to the authors, methods and approaches of building information models of sensory perception of information are given. Such a systematic approach “from simple to complex and from it to generalization” made it possible to determine the features of each of the considered methods, to determine their advantages and disadvantages, and to indicate the directions of appropriate use. The authors proposed and implemented a method of identifying computer users based on the measurement of various time delays when entering information from the computer keyboard. In order to increase the accuracy of identification, it is recommended to use the relative values of pauses before and after pressing a key to the time it is held. This approach provides a 15%increase in recognition accuracy and reduces time and resource costs for identification. In order to automate the process of identification of a person working at a computer for a long time, adaptation of the developed product to changing the user’s keyboard handwriting by changing the handwriting sample is provided. Considerable attention is paid to clarifying the concepts of sign, image, meaning, meaning, which reflect the psychological aspects of information perception by a computer user.

Precarious Bureaucratic Waiting and the Measurement of Delay at the East Jerusalem Ministry of Interior

When Palestinian Jerusalemites refer to “the ministry” (al-dakhliya), they also refer to the sense of weightiness, lost time, frustration, exhaustion, and anxiety that accumulate to the Israeli Ministry of Interior located in the East Jerusalem neighborhood of Wadi al-Joz. Multiple pressures and limited access produce tedious and outright cruel conditions for Palestinians visiting the institution. This essay attends to the affective associations and meanings the institution represents to Palestinians in Jerusalem by drawing on the author’s own experiences there and while conducting ethnographic fieldwork, including conversations and interviews with interlocutors, journalistic reporting, fiction writing, and an examination of Google reviews of the ministry. It attempts to appreciate how the experience of delay at the ministry is configured as a tool of punishment within the context of ongoing Israeli settler colonialization.

Cloud Control of Connected Vehicle Under Both Communication-Induced Sensing and Control Delay: A Prediction Method

In this paper, we focus on the problem of cloud control of the connected vehicle with time-varying communication-induced sensing delay and control delay. First, the connected vehicle cloud control system containing communication-induced delay is modeled as the discrete linear output feedback system with bounded input and output delay. Second, corresponding to the linear output feedback system, the “predictor-observer” structured controller is introduced and redesigned to compensate for the delay in both output and input channels actively, without measurement of actual input delay as its original version. The stability of the close-looped prediction-based control system under a certain delay boundary is analyzed, and the sufficient stability condition is proposed. Third, with the help of Cone Complementary Linearization (CCL), an iterative algorithm is proposed to design stabilized controller and observer gains. Finally, the proposed method is verified through vehicle lateral and longitudinal control simulations, and the effectiveness and the performance of the proposed delay compensation strategy are innovatively evaluated under real vehicle control scenarios.

Moving Object Localization in Distributed MIMO With Clock and Frequency Offsets

This paper investigates the localization problem of the moving target in distributed multiple-input multiple-output (MIMO) systems, where the transmitters are subject to clock and frequency offsets. The position and velocity of the moving target are jointly determined by applying time delay (TD) and Doppler shift (DS) measurements. For this purpose, two efficient solution approaches are proposed to estimate the unknowns of the moving target, as well as the clock and frequency offsets. Firstly, the nonconvex localization problem is first relaxed into a convex semidefinite programming (SDP) form. Additionally, a two-stage closed-form solution (TSCFS) approach is proposed to determine the unknowns. The performance of the proposed methods is examined by the mean squared error (MSE) analysis. The simulated results show that the performance of the proposed solutions are able to approach the Cramér-rao lower bound (CRLB) accuracy at low noise levels. In contrast, the SDP solution performs better than the TSCFS in the presence of high noise levels or a small number of receivers.

Performance of Multidevice Downlink Cell-Free System Under Finite Blocklength for uRLLC With Hard Deadlines

As an important part of beyond the fifth-generation (B5G) and the sixth-generation (6G) mobile communication systems, ultra-reliable and low latency communications (uRLLC) puts forward strict requirements for delay and reliability (e.g., 99.9999% reliability and 500 μs latency). At present, the evaluation measures of delay and reliability are usually based on infinite block length and rely on long-term statistics, which cannot meet the requirement of low latency. The cell-free system, with a very large number of distributed antennas, has the characteristics of macro-diversity and spatial sparsity, which can further enhance the performance of uRLLC. In this paper, the downlink multidevice cell-free system with hard deadlines is considered and analyzed in the finite block length (FBL) regime. The communication’s delay and reliability are described based on two instantaneous evaluation measures: transmission error (TE) and time overflow (TO) probability. From the perspective of information theory, this paper analyzes the analytic expression of TE probability for a single device and the performance impact of FBL on the traditional channel capacity analysis. Considering the multidevice TO probability in a cell-free system, the closed-form expressions of upper and lower bounds are derived and compared with the gamma approximation results. This paper further provides three methods, namely, transmission rate selection, device grouping and space division multiplexing, to balance the delay and reliability of the system and analyzes the performance.

TOTAL FLOAT MANAGEMENT TECHNIQUE UNDER THE FLOAT AND RESOURCE LOADING

Schedule delays in construction projects are a common occurrence and have a significant impact on the overall project duration. Plentiful delay analysis techniques have been proposed and utilized to resolve these issues.The total float management method is widely accepted and considered the most fundamental approach as it effectively resolves four major delay issues and measures float consumption. However, current delay analysis techniques have often overlooked the allocation of float and resources, which can remarkably affect the determination of delay responsibilities for involved parties. This study aims to enhance the total float management approach by intensively incorporating float and resource loading considerations before delayanalysis implementation. The research methodology includes an extensive literature review, identification of crucial issues related to schedule delays arising from the lack of resource and total float allocation, and the application of enhanced total float management under float and resource loading through a case study for test validation. The research findings provide transparent insights into delay liability considering both time delays and float consumption and emphasize the importance of float and resource allocation in the early stages of construction projects for a consensus before analyzing and assigning delay responsibilities. Future studies could focus on legalizing the procedural considerations of float ownership and resource allocation in contractagreements.

Computer Network Optimization Using Queue Tree and Peer Connection Queue (PCQ) Method at SMK Negeri 1 Sumbawa for Learning Support

Bandwidth struggles and non-optimal internet networks can result in connection problems, such as slow connections and allowing users not to connect to the internet. therefore it is necessary to optimize computer networks to be able to maximize service to users, both used to find information, download and upload data. This study uses the Queue Tree and PCQ methods which aim to optimize computer networks at SMKN 1 Sumbawa Besar and improve the quality of computer networks in terms of delay, jitter, throughput, and packet loss. This type of research is qualitative and quantitative research. Research methods include data collection (observation, interviews, literature study), analysis, design, implementation, and testing. Based on the test results after using the Queue Tree and PCQ methods, the average values of delay, jitter, throughput, and packet loss are more optimal than before applying the Queue Tree and PCQ methods. The delay measurement in data rate before applying the Queue Tree and PCQ methods is 1414925 m/s and after applying the Queue Tree and PCQ average delay is 3,165 ms. Test Jitter on the data rate before applying Queue Tree and PCQ methods is 1414957 ms and after applying the queue tree and PCQ jitter is 3,164 ms, Throughput on data rates before applying the Queue Tree and PCQ methods is 5043 kbps and after applying the queue tree and PCQ throughput is 2486 kbps, Test packet loss on data rates before applying the Queue Tree and PCQ methods is 7,911% and after applying the queue tree and PCQ methods is 0,030%.

Rain conditions effect the transmission of Streaming video data on Aeromodelling

Streaming is the process of sending data continuously or continuously that be broadcast over the internet. FPV (First-person view) is a method used to control radio control vehicles from the pilot. Analysis of live video streaming service on FPV aeromodelling with standard configurations to determine the maximum results for live video streaming service on FPV aeromodelling. Distance measurements and environmental conditions are also necessary to determine the performance of live video streaming. Then performed a Quality of Service (QoS) analysis, including measurement of delay, jitter, and throughput using Wireshark. From the tests that have been carried out, the comparison of the best value between the measurement of data delay with a value of 0.0085 m/s, for a jitter of 20.294 m/s and a throughput of 0.009 m/s is obtained, all of which are in accordance with the standards recommended by ITU-T, so that the overall QoS obtained gives sufficient results

ELoran Propagation Delay Prediction Model Based on a BP Neural Network for a Complex Meteorological Environment.

The core of eLoran ground-based timing navigation systems is the accurate measurement of groundwave propagation delay. However, meteorological changes will disturb the conductive characteristic factors along the groundwave propagation path, especially for a complex terrestrial propagation environment, and may even lead to microsecond-level propagation delay fluctuation, seriously affecting the timing accuracy of the system. Aiming at this problem, this paper proposes a propagation delay prediction model based on a Back-Propagation neural network (BPNN) for a complex meteorological environment, which realizes the function of directly mapping propagation delay fluctuation through meteorological factors. First, the theoretical influence of meteorological factors on each component of propagation delay is analyzed based on calculation parameters. Then, through the correlation analysis of the measured data, the complex relationship between the seven main meteorological factors and the propagation delay, as well as their regional differences, are demonstrated. Finally, a BPNN prediction model considering regional changes of multiple meteorological factors is proposed, and the validity of the model is verified by long-term collected data. Experimental results show that the proposed model can effectively predict the propagation delay fluctuation in the next few days, and its overall performance is significantly improved compared with that of the existing linear model and simple neural network model.