Long-term electrical performance and life model fitting of XLPE and EPR insulated cables

1992 ◽  
Vol 7 (2) ◽  
pp. 634-641 ◽  
Author(s):  
M. Cacciari ◽  
G.C. Montanari ◽  
L. Simoni ◽  
A. Cavallini ◽  
A. Motori
Keyword(s):  
Model Fitting ◽  
Electrical Performance ◽  
Life Model

scholarly journals HITS: Hurricane Intensity and Track Simulator with North Atlantic Ocean Applications for Risk Assessment

2015 ◽  
Vol 54 (7) ◽  
pp. 1620-1636 ◽  
Author(s):  
J. Nakamura ◽  
U. Lall ◽  
Y. Kushnir ◽  
B. Rajagopalan
Keyword(s):  
Tropical Cyclone ◽  
North Atlantic Ocean ◽  
Probability Distributions ◽  
Model Fitting ◽  
Simulation Models ◽  
Annual Probability ◽  
Cyclone Tracks ◽  
Probabilistic Coverage ◽  
Tropical Cyclone Tracks

AbstractA nonparametric stochastic model is developed and tested for the simulation of tropical cyclone tracks. Tropical cyclone tracks demonstrate continuity and memory over many time and space steps. Clusters of tracks can be coherent, and the separation between clusters may be marked by geographical locations where groups of tracks diverge as a result of the physics of the underlying process. Consequently, their evolution may be non-Markovian. Markovian simulation models, as are often used, may produce tracks that potentially diverge or lose memory quicker than happens in nature. This is addressed here through a model that simulates tracks by randomly sampling track segments of varying length, selected from historical tracks. For performance evaluation, a spatial grid is imposed on the domain of interest. For each grid box, long-term tropical cyclone risk is assessed through the annual probability distributions of the number of storm hours, landfalls, winds, and other statistics. Total storm length is determined at birth by local distribution, and movement to other tropical cyclone segments by distance to neighbor tracks, comparative vector, and age of track. The model is also applied to the conditional simulation of hurricane tracks from specific positions for hurricanes that were not included in the model fitting so as to see whether the probabilistic coverage intervals properly cover the subsequent track. Consequently, tests of both the long-term probability distributions of hurricane landfall and of event simulations from the model are provided.

The effect of washing on the electrical performance of knitted textile strain sensors for quantifying joint motion

2021 ◽  
pp. 152808372110592
Author(s):  
Cristina Isaia ◽  
Simon McMaster ◽  
Donal McNally
Keyword(s):  
Elbow Flexion ◽  
Strain Sensors ◽  
Electrical Performance ◽  
Market Penetration ◽  
Maximum Extension ◽  
Maximum Flexion ◽  
Flexion Extension ◽  
Textile Sensor ◽  
Simulated Training

Successful market penetration of textile-based strain sensors requires long-term reliability which in turn relies on the washability of the sensor. First, this paper presents an evaluation of the effect of 5 washing cycles on the electrical performance of a knitted conductive transducer, over 1500 cycles of repetitive elongation. The promising behaviour of the textile sensor in this study showed that it might be possible to make a smart garment, capable of quantifying elbow flexion-extension motion, by integrating it into an elbow sleeve. Second, a prototype sleeve, incorporating a knitted sensor (the so-called smart sleeve), was tested in a simulated training/clinical setting by performing 50 flexion-extension cycles after 1, 5, 15, 25, 50 and 75 washes. In both studies, the electrical resistance of the sensor increased with the number of washes in a predictable manner and exhibited a repeatable, reliable and prompt response to elongation. In particular, the electrical pattern representing flexion-extension motion measured using the sleeve was clear and distinguishable up to the 75th wash. Moreover, resistance measurements within the same trial were repeatable at maximum flexion (≤2% variation) and at maximum extension (≤3% variation) and predictable with increasing washes (R2 = 0.992 at maximum flexion and R2 = 0.989 at maximum extension). The good washability of the smart sleeve, evidenced by its ability to detect, distinguish and measure parameters of flexion-extension motion up to 75 washes, makes it a suitable and sustainable choice for applications, such as strength conditioning or rehabilitation, where repetition count and speed are useful.

Long-term hydrolytic capacity evaluation of a thermophilic anaerobic digester treating sewage sludge

2012 ◽  
Vol 66 (11) ◽  
pp. 2378-2384 ◽  
Author(s):  
Andres Donoso-Bravo ◽  
Sara Pérez-Elvira ◽  
Alain Vande Wouwer ◽  
Fernando Fdz-Polanco
Keyword(s):  
Cross Validation ◽  
Model Fitting ◽  
Hydrolytic Activity ◽  
Reaction Model ◽  
Organic Load ◽  
Continuous Reactor ◽  
Term Operation ◽  
Digestion Process ◽  
Capacity Evaluation

This study presents an evaluation of the hydrolytic activity of a continuous thermophilic anaerobic reactor in long-term operation. The hydrolytic coefficient was estimated by fitting a three-reaction model of the anaerobic digestion process with experimental data obtained from a pilot thermophilic digester operated for about 2 years. The model fitting and the cross-validation indicate that this model can represent the behavior of the system in a proper way; moreover, the results show a variation of the hydrolytic capacity of the system throughout the evaluation period. The increase in the hydrolytic coefficient is in agreement with the increase in the organic load applied to the reactor, which shows the capacity of the continuous reactor to select populations according to the input conditions of the system.

scholarly journals Leadless Cardiac Pacemaker: Does Anatomical Position at Implant Affect Long-Term Electrical Performance?

2017 ◽  
Vol 10 (11) ◽  
pp. 500-508
Author(s):  
John Ip ◽  
Abdul R. Safadi ◽  
Randy Ip ◽  
Matthew Gaskill ◽  
Rajesh Banker ◽  
...  
Keyword(s):  
Cardiac Pacemaker ◽  
Electrical Performance ◽  
Anatomical Position

scholarly journals Intracortical probe arrays with silicon backbone and microelectrodes on thin polyimide wings enable long-term stable recordings in vivo

2021 ◽  
Author(s):  
Antje Kilias ◽  
Yu-Tao Lee ◽  
Ulrich P Froriep ◽  
Charlotte Sielaff ◽  
Dominik Moser ◽  
...  
Keyword(s):  
Unit Activity ◽  
Soft Materials ◽  
Tissue Response ◽  
Electrical Performance ◽  
Fixation Method ◽  
Probe Design ◽  
Rear Side ◽  
Tissue Reactions

Abstract Objective. Recording and stimulating neuronal activity across different brain regions requires interfacing at multiple sites using dedicated tools while tissue reactions at the recording sites often prevent their successful long-term application. This implies the technological challenge of developing complex probe geometries while keeping the overall footprint minimal, and of selecting materials compatible with neural tissue. While the potential of soft materials in reducing tissue response is uncontested, the implantation of these materials is often limited to reliably target neuronal structures across large brain volumes. Approach. We report on the development of a new multi-electrode array exploiting the advantages of soft and stiff materials by combining 7-µm-thin polyimide wings carrying platinum electrodes with a silicon backbone enabling a safe probe implantation. The probe fabrication applies microsystems technologies in combination with a temporal wafer fixation method for rear side processing, i.e. grinding and deep reactive ion etching, of slender probe shanks and electrode wings. The wing-type neural probes are chronically implanted into the entorhinal-hippocampal formation in the mouse for in vivo recordings of freely behaving animals. Main results. Probes comprising the novel wing-type electrodes have been realized and characterized in view of their electrical performance and insertion capability. Chronic electrophysiological in vivo recordings of the entorhinal-hippocampal network in the mouse of up to 104 days demonstrated a stable yield of channels containing identifiable multi-unit and single-unit activity outperforming probes with electrodes residing on a Si backbone. Significance. The innovative fabrication process using a process compatible, temporary wafer bonding allowed to realize new Michigan style probe arrays. The wing-type probe design enables a µm-precise probe insertion into brain tissue and long-term stable recordings of unit activity due to the application of a stable backbone and 7-µm-thin probe wings provoking locally a minimal tissue response and protruding from the glial scare of the backbone.

scholarly journals Bristlecone: An F# library for model-fitting and model-selection of ecological time-series data

2019 ◽  
Author(s):  
Andrew C Martin
Keyword(s):  
Time Series ◽  
Model Selection ◽  
Tree Rings ◽  
Time Series Data ◽  
Sediment Cores ◽  
Model Fitting ◽  
Series Data ◽  
Ecological Problems ◽  
Biodiversity And Ecosystem Function

Environmental archives such as sediment cores and tree rings provide important insights on the timing and rates of change in biodiversity and ecosystem function over the long-term. Such datasets are often analysed using empirical methods, which limits their ability to address ecological questions that seek to understand underlying ecological mechanisms and processes. Top down modelling approaches – where data is confronted with simple ecological models – can be used to infer the presence, form, and strength of mechanisms of interest. To aid adoption of time-series mechanistic modelling for long-term ecology, we created a F# library, Bristlecone, that can be used to apply this approach using a Model- Fitting and Model-Selection workflow. Our objective with Bristlecone was to create a library that could be used to efficiency and effectively conduct a full MFMS analysis for long-term ecological problems. We incorporated techniques to address specific challenges with environmental archives, including uneven time steps from age-depth models (for sediment cores), and allometry and seasonality (for tree rings). We include an example analysis to demonstrate functionality of Bristlecone. Our solution presents a straightforward, repeatable, and highly parallel method for conducting inference for long- term ecological problems.

P1466Leadless pacemaker mid and long term follow-up in a single center-study

EP Europace ◽  
2020 ◽  
Vol 22 (Supplement_1) ◽  
Author(s):  
J L Martinez Sande ◽  
J Garcia-Seara ◽  
L Gonzalez-Melchor ◽  
C E Cacho-Antonio ◽  
X A Fernandez-Lopez ◽  
...  
Keyword(s):  
Atrial Fibrillation ◽  
Pacemaker Implantation ◽  
Electrical Performance ◽  
Single Center ◽  
Electrical Parameters ◽  
Single Center Study ◽  
Long Term Follow Up ◽  
Center Study

Abstract Introduction and objectives Initial results of Leadless pacemakers (LPM) has been promising in worldwide, nevertheless there are still no long term experience published, so the objective of our study was to evaluate electrical parameters at mid  and long term follow-up, describing as well total complications and mortality in a single center-study. Methods   This was a prospective, observational clinical trial that included 183 consecutive patients, with an indication for a single-chamber pacemaker implantation. Results   All successful implantation included a total of 183 patients with a mean age of 79,2 ±6,6 years (range 54-93y/o); 111 (60,6%) were men and more frequent rhythm was permanent atrial fibrillation (160), including those in which a node ablation was performed in the same procedure (22). Clinical and echocardiographyc characteristics are described in table 1.Mean follow-up was of 26 ±10 months including: 64 patient at 24 months, 46 at 36 months and 7 patients at 48 months. Electrical parameters are represented in figure 1, which were stable and flawless at long term follow-up.  Total complications were 3,3%, with only 2 patient requiring surgery for resolution (1,7%), and all were acute during LPM implantation. A total of 17 patients (9,3%) died with no relation to pacemaker.  Conclusions In our experience, leadless pacemakers electrical performance continues stable, appropriate at long term follow-up, and no other complications developed. Baseline Characteristics of Patients Age(years) 79.2 ± 6.6[54-93] Male gender, n (%) 118 (60.6%) Hypertension, n (%) 149 (81.7%) Diabetes mellitus, n (%) 64 (34.9%) COPD, n (%) 33(18.3%) Renal dysfunction, n (%) 30 (16.7%) Valvular disease, n (%) 74 (41.1%) Atrial Fibrillation, n (%) 161 (98.0%) LVEF(%) 60.0 ± 8 OAC, n (%) 123(67.2%) NOAC, n (%) 23 (10.0%) Abstract Figure. Electrical performance

Reliability of Ceramic Column Grid Array (CCGA717) Interconnect Packages Under Extreme Temperatures for Space Applications*

2010 ◽  
Vol 7 (1) ◽  
pp. 16-24 ◽  
Author(s):  
Rajeshuni Ramesham
Keyword(s):  
Thermal Cycling ◽  
Experimental Test ◽  
High Reliability ◽  
Extreme Temperature ◽  
Electrical Performance ◽  
Extreme Temperatures ◽  
Thermal Cycles ◽  
Space Applications ◽  
Temperature Range

Ceramic column grid array packages have been increasing in use based on their advantages such as high interconnect density, very good thermal and electrical performance, compatibility with standard surface-mount packaging assembly processes, and so on. CCGA packages are used in space applications such as in logic and microprocessor functions, telecommunications, flight avionics, and payload electronics. As these packages tend to have less solder joint strain relief than leaded packages, the reliability of CCGA packages is very important for short-term and long-term space missions. CCGA interconnect electronic package printed wiring boards (PWBs) of polyimide have been assembled, inspected nondestructively, and subsequently subjected to extreme temperature thermal cycling to assess the reliability for future deep space, short- and long-term, extreme temperature missions. In this investigation, the employed temperature range covers from −185°C to +125°C extreme thermal environments. The test hardware consists of two CCGA717 packages with each package divided into four daisy-chained sections, for a total of eight daisy chains to be monitored. The CCGA717 package is 33 mm × 33 mm with a 27 × 27 array of 80%/20% Pb/Sn columns on a 1.27 mm pitch. The resistance of daisy-chained, CCGA interconnects was continuously monitored as a function of thermal cycling. Electrical resistance measurements as a function of thermal cycling are reported and the tests to date have shown significant change in daisy chain resistance as a function of thermal cycling. The change in interconnect resistance becomes more noticeable as the number of thermal cycles increases. This paper will describe the experimental test results of CCGA testing under extreme temperatures. Standard Weibull analysis tools were used to extract the Weibull parameters to understand the CCGA failures. Optical inspection results clearly indicate that the solder joints of columns with the board and the ceramic package have failed as a function of thermal cycling. The first failure was observed at the 137th thermal cycle and 63.2% failures of daisy chains have occurred by about 664 thermal cycles. The shape parameter extracted from the Weibull plot was about 1.47, which indicates the failures were related to failures that occurred during the flat region or useful life region of the standard bathtub curve. Based on this experimental test data, one can use the CCGAs for the temperature range studied for ∼100 thermal cycles (ΔT = 310°C, 5°C/minute, and 15 min dwell) with a high degree of confidence for high reliability space and other applications.

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