Key Timing Parameters Research Articles

Quantitative Comparison of Color-Coded Parametric Imaging Technologies Based on Digital Subtraction and Digital Variance Angiography: A Retrospective Observational Study.

The evaluation of hemodynamic conditions in critical limb-threatening ischemia (CLTI) patients is inevitable in endovascular interventions. In this study, the performance of color-coded digital subtraction angiography (ccDSA) and the recently developed color-coded digital variance angiography (ccDVA) was compared in the assessment of key time parameters in lower extremity interventions. The observational study included 19 CLTI patients who underwent peripheral vascular intervention at our institution in 2020. Pre- and post-dilatational images were retrospectively processed and analyzed by a commercially available ccDSA software (Kinepict Medical Imaging Tool 6.0.3; Kinepict Health Ltd., Budapest, Hungary) and by the recently developed ccDVA technology. Two protocols were applied using both a 4 and 7.5 frames per second acquisition rate. Time-to-peak (TTP) parameters were determined in four pre- and poststenotic regions of interest (ROI), and ccDVA values were compared to ccDSA read-outs. The ccDVA technology provided practically the same TTP values as ccDSA (r = 0.99, R2 = 0.98, p < 0.0001). The correlation was extremely high independently of the applied protocol or the position of ROI; the r value was 0.99 (R2 = 0.98, p < 0.0001) in all groups. A similar correlation was observed in the change in passage time (r = 0.98, R2 = 0.96, p < 0.0001). The color-coded DVA technology can reproduce the same hemodynamic data as a commercially available DSA-based software; therefore, it has the potential to be an alternative decision-supporting tool in catheter labs.

Embryos from vitrified vs. fresh oocytes in an oocyte donation program: a comparative morphokinetic analysis

To compare the morphokinetic patterns of human embryos originating from vitrified oocytes (VITRI group) with those derived from freshly collected oocytes (CONTROL group) in oocyte donation cycles. This is a retrospective observational study. Embryolab Fertility Clinic, Embryology Lab, Thessaloniki, Greece. The study included embryos from 421 vitrified oocytes from 58 oocyte donation cycles and 196 fresh oocytes from 23 oocyte donation cycles. None. Key time parameters, dynamic events, fertilization rates, degeneration rates, cleavage rates, blastocyst rates, pregnancy rates, clinical pregnancy rates, implantation rates, and live birth rates were estimated. The mean survival rate of vitrified oocytes was 92.58% (±7.42%). Fertilization rates were significantly different between the 2 groups (VITRI group: 71.92% ± 20.29% and CONTROL group: 80.65% ± 15.22%) whereas the degeneration, cleavage, blastocyst, pregnancy, clinical pregnancy, ongoing pregnancy, implantation, and live birth rates were not significantly different between embryos derived from fresh or vitrified oocytes. Time-lapse analysis showed no significant difference in any key time parameter. However, when examining dynamic parameters, first cell cycle (CC1) (t2 - tPB2: from the second polar body extrusion (tPB2) up to 2 cells (t2)) showed a significant difference whereas CC1a (t2 - tPNf: from fading of the pronuclei (tPNf) up to 2 cells (t2)) was at the threshold of significance. CC1 in vitrified oocytes exhibited a comparatively slower progression in contrast to fresh oocytes. Conversely, CC1a in vitrified oocytes demonstrated faster progression compared with fresh oocytes. It is worth noting that these temporary deviations had minimal impact on the subsequent development. Despite the clinical outcomes showing a decrease in the vitrified group, none of them reached statistical significance. This lack of significance could be attributed to the limited sample size of the study.

P-184 Morphokinetic analysis of cases with vitrified-warmed oocytes in oocyte donation program

Abstract Study question Does vitrification of oocytes in oocyte donation program alter the morphokinetic pattern of human embryos? Summary answer Both the extrusion of the second polar body (tPB2) and the appearance of the pronuclei (tPNa) occur earlier in vitrified oocytes without affecting further development. What is known already Vitrification of oocytes has been a breakthrough in oocyte cryopreservation and significantly altered practices in IVF labs. Oocyte vitrification/warming has become an integral part of daily routine and thorough assessment of its efficiency is crucial. Though, studies of vitrified-warmed oocytes have shown similar fertilization, cleavage, blastulation, pregnancy and live birth rates to fresh oocytes, the morphokinetic pattern of embryos originating from vitrified oocytes has not been thoroughly studied. According to some studies vitrification may be related to delayed blastocyst formation while others failed to see any alteration in the morphokinetic pattern between embryos derived from fresh or frozen oocytes. Study design, size, duration This retrospective observational study was performed at Embryolab Fertility Clinic, in Thessaloniki, Greece between April 2020 and September 2021 and included 590 vitrified oocytes from 68 oocyte donation cycles. Control group consisted of 31 good prognosis cases (oocyte donation cycles or homologous oocyte cycles of women under 35 years old). Participants/materials, setting, methods 68 vitrified oocyte donation cycles and 31 fresh control cycles were analyzed. All oocytes after ICSI were cultured in Embryoscope time-lapse incubator up to blastocyst stage. Key time parameters and dynamic events were analyzed using generalized estimating equations (GEE) regression analysis for the non-independent nature of the data. Moreover, the following comparisons were performed between groups: fertilization, cleavage, top cleavage, blastocyst, top blastocyst and pregnancy rates. Main results and the role of chance There was no significant difference in fertilization rates between control and frozen oocytes (77.79% ± 15.73 vs 71.26% ± 21.50 respectively, p = 0.15). Cleavage rate and top cleavage rate (more than 6 cells, equal size, with no or minor fragmentation), were higher in frozen oocytes with this difference being significant (p = 0.02 for cleavage rate and p = 0.015 for top cleavage rate). Blastocyst rate and top blastocyst (2AA, 3AA, 3AB, 4AA, 4AB according to Gardner criteria) rate, though, showed similar rates with no statistically significant difference (Blastocyst rate: 74,15% ± 17.19-control vs 76.42% ± 30.75-frozen oocytes, p = 0.6 &amp; Top blastocyst rate: 45.54% ± 24.04-control, 45.30% ± 32.04-frozen oocytes, p = 0.82). Pregnancy rates were not significantly different (control:85.19%, frozen oocytes:75.38%, p = 0.29). The comparison for key time parameters and dynamic events that were analyzed (tPB2, tPNa, tPNf, t2, t3,t4, t5, t6, t7, t8, t9+, tSC, tM, tSB, tB, tEB, S2, S3, S5, CC1, CC2, CC3,Compaction and Blastulation) showed significant difference in 2 time parameters: tPB2 (4.62 hours-control, 3.67 hours-frozen, Coef: -1.09, p = 0.015) and tPNa (9.07 hours-control, 8.25 hours-frozen oocytes, Coef: -1.06, p = 0.043). Limitations, reasons for caution The fact that the oocytes under comparison were not sibling as well as its retrospective nature, constitute the main limitations of the present study. Moreover, the number of cases included in this study was limited and the available information about ongoing pregnancy and live births is still pending. Wider implications of the findings tPB2 and tPNa seem to occur earlier in vitrified oocytes without affecting further development, implying a need for reviewing timings between OPU/vitrification/warming/ICSI. Moreover, vitrified oocytes displayed higher cleavage and top cleavage rates with unaffected blastocyst or pregnancy rates. Overall, vitrification of oocytes seems to be safe and reliable. Trial registration number N/A

Experimental study on stepping performance of the control rod hydraulic drive system

Control rod hydraulic drive system (CRHDS) is a new type of built-in control rod drive technology. The circuit flow resistance and driving pressure have significant effects on the stepping performance. The related experiments were conducted. Moreover, the mechanisms of step-up and step-down processes were analyzed and the performance characteristic parameters were obtained. Based on the experimental results, the variations of key parameters were analyzed. The analysis results show that the step-up and step-down processes can be divided into three stages, and displacement, cylinder pressure and flowrate correspond to each other. With the increase of circuit flow resistance, the key time parameters of step-up and step-down processes change first rapidly then slowly. With the increase of driving pressure, the step-up time decreases gradually, the step-down time changes little, and the time of pressure change increases slightly. The research results lay the base for the design and optimization for the CRHDS.

Performance and Power Estimation of STT-MRAM Main Memory with Reliable System-level Simulation

It is questionable whether DRAM will continue to scale and will meet the needs of next-generation systems. Therefore, significant effort is invested in research and development of novel memory technologies. One of the candidates for next-generation memory is Spin-Transfer Torque Magnetic Random Access Memory (STT-MRAM). STT-MRAM is an emerging non-volatile memory with a lot of potential that could be exploited for various requirements of different computing systems. Being a novel technology, STT-MRAM devices are already approaching DRAM in terms of capacity, frequency, and device size. Although STT-MRAM technology got significant attention of various major memory manufacturers, academic research of STT-MRAM main memory remains marginal. This is mainly due to the unavailability of publicly available detailed timing and current parameters of this novel technology, which are required to perform a reliable main memory simulation on performance and power estimation. This study demonstrates an approach to perform a cycle accurate simulation of STT-MRAM main memory, being the first to release detailed timing and current parameters of this technology from academia—essentially enabling researchers to conduct reliable system-level simulation of STT-MRAM using widely accepted existing simulation infrastructure. The results show a fairly narrow overall performance deviation in response to significant variations in key timing parameters, and the power consumption experiments identify the key power component that is mostly affected with STT-MRAM.

A Generic Methodology for Calculating Rescheduling Time for Multiple Unexpected Events in the Era of Zero Defect Manufacturing

Nowadays, the manufacturing industry is constantly changing. Production systems must operate in a highly dynamic environment where unexpected events could occur and create disruption, making rescheduling inevitable for manufacturing companies. Rescheduling models are fundamental to the robustness of production processes. This paper proposes a model to address rescheduling caused by unexpected events, aiming to achieve the zero-defect manufacturing (ZDM) concept. The goal of the model is to incorporate traditional and ZDM–oriented events into one methodology to calculate when the next rescheduling will be performed to effectively react to unexpected events. The methodology relies on the definition of two key time parameters for each event type: event response time (RT) and event delay response time (DRT). Based on these parameters, an event management algorithm is designed to identify the optimal rescheduling solution. The DRT parameter is calculated based on a multi-parametric dynamic formula to capture the dynamics of production. Moreover, ANOM, and ANOVA methods are used to analyse the behaviour of the developed method and to assess the level of robustness of the proposed approach. Finally, a case study based on real production scenarios is conducted, a series of simulation experiments are performed, and comparisons with other rescheduling policies are presented. The results demonstrate the effectiveness of the proposed event management algorithm for managing rescheduling.

Key Technology Practice of High-Speed Access and Research on the Temperature Dependence of Key Time Parameters Based on NAND Flash Memory

This paper focuses on the NAND flash memory as a data storage medium in the Internet of things data acquisition system, which plays an important role from beginning to end. The flow process of multi-channel sensor data sampling, holding, conversion, coding, and storage in the data acquisition system is described. The basic working principle and working process of NAND flash memory are introduced. Based on Interleaved Two-plane Program Technology, and the solution of burst massive throughput in high-speed data transmission is proposed. Compared with previously published papers, the temperature dependence of key time parameters of NAND flash memory is studied and analyzed under the condition of temperature change more concretely. The changing trend of three key time parameters of NAND type flash under different temperatures is analyzed by using appropriate test samples. At the same time, the analysis of the causes of reflection from the phenomenon is further expanded and discussed. The combination of theory and practice can provide powerful suggestions for more efficient and accurate application of NAND flash memory.

Understanding Scanner Utilization With Real-Time DICOM Metadata Extraction.

Understanding system performance metrics ensures better utilization of the radiology resources with more targeted interventions. The images produced by radiology scanners typically follow the DICOM (Digital Imaging and Communications in Medicine) standard format. The DICOM images consist of textual metadata that can be used to calculate key timing parameters, such as the exact study durations and scanner utilization. However, hospital networks lack the resources and capabilities to extract the metadata from the images quickly and automatically compute the scanner utilization properties. Thus, they resort to using data records from the Radiology Information Systems (RIS). However, data acquired from RIS are prone to human errors, rendering many derived key performance metrics inadequate and inaccurate. Hence, there is motivation to establish a real-time image transfer from the Picture Archiving and Communication Systems (PACS) to receive the DICOM images from the scanners to research clusters to conduct such metadata processing to evaluate scanner utilization metrics efficiently and quickly. This paper analyzes the scanners’ utilization by developing a real-time monitoring framework that retrieves radiology images into a research cluster using the DICOM networking protocol and then extracts and processes the metadata from the images. Our proposed approach facilitates a better understanding of scanner utilization across a vast healthcare network by observing properties such as study duration, the interval between the encounters, and the series count of studies. Benchmarks against using the RIS data indicate that our proposed framework based on real-time PACS data estimates the scanner utilization more accurately. Furthermore, our framework has been running stable and performing its computation for more than two years on our extensive healthcare network in pseudo real-time.

Study on Optimization of Coal Truck Flow in Open‐Pit Mine

A semicontinuous process system consisting of a single‐bucket excavator, truck, crushing station, and belt conveyor is the main coal mining process system of a large‐scale hard coal open‐pit mine. Through analyzing the coal mining production process, the key issues of coal mining truck flow optimization are obtained. Statistical method of using triangular fuzzy numbers analyzes the key time parameters of coal mining truck flow. Taking one shift, the minimum expected value of number of trucks, as the objective function, the fuzzy expectation of the coal mining semicontinuous process system is established with the constraints of the truck flow continuity at the loading and unloading point, the production capacity of the electric shovel, the production capacity of the crushing station, coal quality, and coal mining production tasks. The truck flow planning model is solved using particle swarm intelligence algorithm. The simulation results show that the result of truck flow planning can effectively reduce truck number, truck dispatching number, transportation costs, and truck queuing. The fuzzy expected truck flow planning model established by the study is suitable for solving the problem of optimizing and matching the production capacity in the process which links electric shovel, truck, and crushing station. It can effectively improve the production efficiency of electric shovel mining, truck transportation, and crushing station.

Review of external referrals to a regional stroke centre: it is not just about thrombectomy

To determine the experience of a regional stroke referral centre of external referrals for endovascular thrombectomy (EVT) in patients with symptoms of acute ischaemic stroke (AIS) and large vessel occlusion (LVO). Data were collected prospectively over two 4-month periods (2017-2018) on consecutive external referrals for EVT. Baseline demographics, imaging findings, and key time parameters were recorded. Reasons for not transferring patients and for not performing EVT were recorded. Key time intervals were calculated and compared between the transferred and non-transferred group with and without intracranial occlusion and between the transferred patients who underwent thrombectomy and those who did not. Two hundred and sixty-two patients were referred. Sixty-one percent (n=159) were accepted and transferred for treatment. Of those transferred, 86% (n=136) had EVT. Fourteen percent (n=23) were unsuitable for EVT on arrival due to no vessel occlusion (48% n=11), poor Alberta Stroke Program Early CT Score (ASPECTS)/established infarct (30%, n=7) haemorrhage (9%, n=2), and clinical recovery (13% n=3). One hundred and three patients (39%) were ineligible for EVT following phone discussion due to absence of intracranial occlusion (59%, n=61), low ASPECTS (22%, n=23), distal occlusion (4%, n=4), low/improving National Institutes of Health Stroke Scale (NIHSS; 10.7%, n=11), and poor modified Rankin Scale (mRS) at baseline (3%, n=3). Patients with LVO but not transferred had longer onset to hospital arrival time compared with those transferred 151.5 versus 91 minutes (p<0.005), with a trend also toward a longer door to CT/CTA 40 minutes versus 30 minutes (p=0.142). These data provide valuable insights into the service provision of a comprehensive stroke network. The present rates of EVT and futile transfers are modest compared to published data. Access to neuroradiology and specialised stroke assessment is crucial to optimise time to treatment.

Replicating the Recovery following the 2014 South Napa Earthquake using Stochastic Process Models

Post-earthquake recovery models can be used as decision support tools for pre-event planning. However, due to a lack of available data, there have been very few opportunities to validate and/or calibrate these models. This paper describes the use of building damage, permitting, and repair data from the 2014 South Napa Earthquake to evaluate a stochastic process post-earthquake recovery model. Damage data were obtained for 1,470 buildings, and permitting and repair time data were obtained for a subset (456) of those buildings. A “blind” prediction is shown to adequately capture the shape of the recovery trajectory despite overpredicting the overall pace of the recovery. Using the mean time to permit and repair time from the acquired data set significantly improves the accuracy of the recovery prediction. A generalized model is formulated by establishing statistical relationships between key time parameters and endogenous and exogenous factors that have been shown to influence the pace of recovery.

Study on Influential Factors of ATSE Transfer Time Based on Orthogonal Polynomial Curve-Fitting

Study on transfer time of Automatic transfer switching equipment (ATSE) has been an important part in the process of switch design and development. Starting from analysis of the electrical operational performance test of ATSE, relationship of all key time parameters during its transfer cycle are researched. Then, the circuit and the test method that can satisfy the requirement of the test are designed, and tests on various types of ATSE are completed. Finally, orthogonal polynomial curve-fitting method is introduced, suitable polynomial for fitting analysis on the test data is explored, key factors influencing the transfer time is discovered, and hidden relationship between each other is found, which provide guidance for designing more stable ATSE and carrying out better electrical performance test.

Note: Electronic circuit for two-way time transfer via a single coaxial cable with picosecond accuracy and precision

We have designed, constructed, and tested the overall performance of the electronic circuit for the two-way time transfer between two timing devices over modest distances with sub-picosecond precision and a systematic error of a few picoseconds. The concept of the electronic circuit enables to carry out time tagging of pulses of interest in parallel to the comparison of the time scales of these timing devices. The key timing parameters of the circuit are: temperature change of the delay is below 100 fs/K, timing stability time deviation better than 8 fs for averaging time from minutes to hours, sub-picosecond time transfer precision, and a few picoseconds time transfer accuracy.

Neuronal oscillations and visual amplification of speech

It is widely recognized that viewing a speaker's face enhances vocal communication, although the neural substrates of this phenomenon remain unknown. We propose that the enhancement effect uses the ongoing oscillatory activity of local neuronal ensembles in the primary auditory cortex. Neuronal oscillations reflect rhythmic shifting of neuronal ensembles between high and low excitability states. Our hypothesis holds that oscillations are 'predictively' modulated by visual input, so that related auditory input arrives during a high excitability phase and is thus amplified. We discuss the anatomical substrates and key timing parameters that enable and constrain this effect. Our hypothesis makes testable predictions for future studies and emphasizes the idea that 'background' oscillatory activity is instrumental to cortical sensory processing.

The PDCA and CAPD economic models of the P control chart

Recently, more attention has been paid to the PDCA and CAPD processes of quality management for raising the efficiency of management in the industry (Ikezawa, 1985; Shiba and Walden, 2001; Matsui, 2005). When the P control chart is used in the short production run, in order to raise the efficiency of management, two cases often take place. One case starts from deciding the control lines, and then maintains the process with them; the other case starts from searching an assignable cause in the out-of-control state. In this paper, we propose both the PDCA and CAPD model of P control chart based on these two cases, and show their mathematical formulations. Then, from an economic viewpoint, we discuss the effect of Pa (power) on Ct (the total expectation cost) of the two models, and investigate the optimal value of sampling interval (vi) to minimise Ct in detail. Finally, by numerically analysing the two models, we found the new relationship between the key time parameters and Ct, respectively.

Landsat-5 bumper-mode geometric correction

The Landsat-5 Thematic Mapper (TM) scan mirror was switched from its primary operating mode to a backup mode in early 2002 in order to overcome internal synchronization problems arising from long-term wear of the scan mirror mechanism. The backup bumper mode of operation removes the constraints on scan start and stop angles enforced in the primary scan angle monitor operating mode, requiring additional geometric calibration effort to monitor the active scan angles. It also eliminates scan timing telemetry used to correct the TM scan geometry. These differences require changes to the geometric correction algorithms used to process TM data. A mathematical model of the scan mirror's behavior when operating in bumper mode was developed. This model includes a set of key timing parameters that characterize the time-varying behavior of the scan mirror bumpers. To simplify the implementation of the bumper-mode model, the bumper timing parameters were recast in terms of the calibration and telemetry data items used to process normal TM imagery. The resulting geometric performance, evaluated over 18 months of bumper-mode operations, though slightly reduced from that achievable in the primary operating mode, is still within the Landsat specifications when the data are processed with the most up-to-date calibration parameters.

Timing quantization error in lidar speed-measurement devices

Minimizing the timing quantization error of lidar speed-measurement devices is an important step in reducing the magnitude of the speed-measurement errors associated with these devices. This paper presents a statistical model for the timing quantization error and demonstrates how this model can be used to select the values of key timing parameters. The values of these parameters must be carefully selected so that manufactured equipment meets current model lidar speed-measurement device performance standards established by the National Highway Traffic Safety Administration (NHTSA).

Frame alignment in a digital carrier system-a tutorial

Four key timing parameters that are used as performance measures are defined; reframe time, false in-frame time, out-of-frame detection time, and misframe time. Several strategies that improve frame alignment performance are considered for the case of a burst frame alignment word (FAW). With a little modification, the same strategies could also be applied to the case of a distributed FAW. The probability generating function is introduced, and its derivation from a state transition diagram is presented. The probability generating function is used in the timing parameters estimation. As an example, the frame alignment of a SONET (synchronized optical network) STS-3 signal is discussed.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>