Pipeline muffling and a priori current ramping: architectural techniques to reduce high-frequency inductive noise

2003 ◽  
Author(s):  
M.D. Powell ◽  
T.N. Vijaykumar
Keyword(s):  
High Frequency ◽  
A Priori ◽  
Inductive Noise

Blind Deconvolution for Two-Thermocouple Sensor Characterization

2006 ◽  
Vol 129 (2) ◽  
pp. 194-202 ◽  
Author(s):  
Peter C. Hung ◽  
Robert J. Kee ◽  
George W. Irwin ◽  
Seán F. McLoone
Keyword(s):  
High Frequency ◽  
Blind Deconvolution ◽  
Low Cost ◽  
A Priori ◽  
Harsh Environment ◽  
Test Rig ◽  
Frequency Signal ◽  
High Frequency Signal ◽  
Automotive Engine ◽  
Algorithmic Compensation

Thermocouples are one of the most popular devices for temperature measurement due to their robustness, ease of manufacture and installation, and low cost. However, when used in the harsh environment found in combustion systems and automotive engine exhausts, large wire diameters are required and consequently the measurement bandwidth is reduced. This paper describes two new algorithmic compensation techniques based on blind deconvolution to address this loss of high-frequency signal components using the measurements from two thermocouples. In particular, a continuous-time approach is proposed, combined with a cross-relation blind deconvolution for parameter estimation. A feature of this approach is that no a priori assumption is made about the time constant ratio of the two thermocouples. The advantages, including small estimation variance and limitations of the method, are highlighted using results from simulation and test rig studies.

A New Method for Evaluation of Cavitation Near Mechanical Heart Valves

2003 ◽  
Vol 125 (5) ◽  
pp. 663-670 ◽  
Author(s):  
Peter Johansen ◽  
Keefe B. Manning ◽  
John M. Tarbell ◽  
Arnold A. Fontaine ◽  
Steven Deutsch ◽  
...  
Keyword(s):  
High Frequency ◽  
Heart Valves ◽  
A Priori ◽  
Pressure Fluctuations ◽  
Mechanical Heart Valves ◽  
New Method ◽  
Pass Filter ◽  
Bandwidth Limitation ◽  
High Pass

Evaluation of cavitation in vivo is often based on recordings of high-pass filtered random high-frequency pressure fluctuations. We hypothesized that cavitation signal components are more appropriately assessed by a new method for extraction of random signal components of the pressure signals. We investigated three different valve types and found a high correlation between the two methods r2:0.8806−0.9887. The new method showed that the cavitation signal could be extracted without a priori knowledge needed for setting the high-pass filter cut off frequency, nor did it introduce bandwidth limitation of the cavitation signal.

scholarly journals Penerapan Data Mining Apriori Pada Persediaan Obat (Studi Kasus Apotek Rafif Farma Medan)

2019 ◽  
Vol 3 (2) ◽  
pp. 115
Author(s):  
Mardiah Mardiah
Keyword(s):  
Data Mining ◽  
Phase Analysis ◽  
Customer Service ◽  
Association Rule ◽  
High Frequency ◽  
A Priori ◽  
Inventory Systems ◽  
Frequent Pattern ◽  
Apriori Algorithm ◽  
Analysis Algorithm

<span><em>The importance of inventory systems at a pharmacy and the type of goods which</em><br /><span><em>are a top priority that must be in stock. It is useful to anticipate the void stuff. Due to the</em><br /><span><em>lack of inventory may affect customer service and asset to the pharmacy. Therefore, this</em><br /><span><em>study was conducted to help resolve those problems by designing a data mining</em><br /><span><em>application that serves to predict sales of the drug is needed most knowable a priori</em><br /><span><em>algorithm with the help of Tools Tanagra. One of the interesting association analysis</em><br /><span><em>phase analysis algorithm that generates a high frequency patterns (frequent pattern</em><br /><span><em>mining).</em><br /><span><em>Keywords: Data Mining, Apriori Algorithm, Association Rule</em></span></span></span></span></span></span></span></span><br /><br class="Apple-interchange-newline" /></span>

scholarly journals Inverse modelling of national and European CH<sub>4</sub> emissions using the atmospheric zoom model TM5

2005 ◽  
Vol 5 (1) ◽  
pp. 1007-1066 ◽  
Author(s):  
P. Bergamaschi ◽  
M. Krol ◽  
F. Dentener ◽  
A. Vermeulen ◽  
F. Meinhardt ◽  
...  
Keyword(s):  
High Frequency ◽  
A Priori ◽  
A Priori Estimate ◽  
European Countries ◽  
Synoptic Scale ◽  
Source Attribution ◽  
Top Down ◽  
Priori Estimate ◽  
Ch4 Emissions ◽  
Model Driven

Abstract. A synthesis inversion based on the atmospheric zoom model TM5 is used to derive top-down estimates of CH4 emissions from individual European countries for the year 2001. We employ a model zoom over Europe with 1°&amp;times1° resolution that is two-way nested into the global model domain (with resolution of 6°×4°). This approach ensures consistent boundary conditions for the zoom domain and thus European top-down estimates consistent with global CH4 observations. The TM5 model, driven by ECMWF analyses, simulates synoptic scale events at most European and global sites fairly well, and the use of high-frequency observations allows exploiting the information content of individual synoptic events. A detailed source attribution is presented for a comprehensive set of 56 monitoring sites, assigning the atmospheric signal to the emissions of individual European countries and larger global regions. The available observational data put significant constraints on emissions from different regions. Within Europe, in particular several Western European countries are well constrained. The inversion results suggest up to 50–90% higher anthropogenic CH4 emissions in 2001 for Germany, France and UK compared to reported UNFCCC values, but the derived EU-15 totals are relatively close to UNFCCC values (within 10–30%). The derived top-down estimate for Finland is distinctly smaller than the a priori estimate, suggesting much smaller CH4 emissions from Finnish wetlands than derived from the bottom-up inventory.

scholarly journals Implementasi Algoritma Apriori Pada Penyusunan Menu Makanan Rumah Makan Prasmanan

2020 ◽  
Vol 6 (2) ◽  
Author(s):  
Asep Budiman Kusdinar ◽  
Daris Riyadi ◽  
Asriyanik Asriyanik
Keyword(s):  
Data Mining ◽  
Association Rules ◽  
Association Rule ◽  
High Frequency ◽  
A Priori ◽  
Apriori Algorithm ◽  
Frequency Pattern ◽  
Data Mining Techniques ◽  
Rule Method

A buffet restaurant is a restaurant that provides buffet food that is served directly at the dining table so that customers can order more food according to their needs. This study uses the association rule method which is one of the methods of data mining and a priori algorithms. Data mining is the process of discovering patterns or rules in data, in which the process must be automatic or semi-automatic. Association rules are one of the techniques of data mining that is used to look for relationships between items in a dataset. While  the apriori algorithm is a very well-known algorithm for finding high-frequency patterns, this a priori algorithm is a type of association rule in data mining. High- frequency patterns are patterns of items in the database that have frequencies or support. This high-frequency pattern is used to develop rules and also some other data mining techniques. The composition of the food menu in the Asgar restaurant is now arranged randomly without being prepared on the food menu between one another. The result of this research is  to support the composition of the food menu at the Asgar restaurant so that it is easier to take food menu with one another.  

Imaging the Samos 2020 Mw7.0 earthquake rupture by backprojecting local strong-motion recordings and relocating the aftershock sequence

2021 ◽  
Author(s):  
Ioannis Fountoulakis ◽  
Christos P. Evangelidis ◽  
Olga-Joan Ktenidou
Keyword(s):  
High Frequency ◽  
A Priori ◽  
Research Work ◽  
Strong Motion ◽  
Aftershock Sequence ◽  
Earthquake Rupture ◽  
Moment Tensors ◽  
Research And Innovation ◽  
Frequency Radiation ◽  
High Frequency Radiation

&lt;p&gt;On November 30, 2020 11:51 UTC, a major earthquake (Mw7.0) struck the northern area offshore Samos island, Greece, causing serious damage to the island and nearby Turkish coast. This seismic event is an ideal opportunity to explore extensional seismicity in the back-arc area of the Hellenic subduction zone. To that end, first and foremost we study the behavior and characteristics of the main event source. Then, we examine the evolution of the aftershock in space and time and relate it to the main event. We implement the technique of local backprojection on strong-motion recordings&amp;#160; (e.g. Kao &amp; Shan, 2007; Evangelidis, 2013) to infer the spatiotemporal distribution of the earthquake source. This method is performed at relatively short periods, making it possible to map in detail the high-frequency radiation of the source, without imposing any a priori constraints on the geometry or shape of the ruptured fault. Furthermore, and which is not often the case, the strong-motion recordings were carefully assessed prior to being used in backprojection, in order to avoid any significant influence of local site effects and amplification, which could in impact the robustness of the backprojection solution. Synthetic tests were also used to resolve the accuracy. Our results show evidence of multiple distinct sources of high-frequency radiation during the earthquake rupture. In addition, the first month of the aftershock sequence was located, clustered and relocated, ultimately highlighting the faults activated in the area. The quality of the resulting high-resolution catalogue was further assessed, and the moment tensors of the strongest events were estimated. Combining the backprojection results with the detailed picture of the aftershock seismic sequence leads to an interpretation of the short- and long-term fault rupture process and their associated secondary effects (tsunami, landslides) in the area.&amp;#160;&lt;/p&gt;&lt;p&gt;The research work was supported by the Hellenic Foundation for Research and Innovation (H.F.R.I.) under the &amp;#8220;First Call for H.F.R.I. Research Projects to support Faculty members and Researchers and the procurement of high-cost research equipment grant&amp;#8221; (SIREN, Project Number: 910).&lt;/p&gt;&lt;p&gt;&amp;#160;&lt;/p&gt;

Imaging the rupture process of recent earthquakes using backprojection of local high frequency records

2020 ◽  
Author(s):  
Ioannis Fountoulakis ◽  
Christos Evangelidis ◽  
Olga-Joan Ktenidou
Keyword(s):  
High Frequency ◽  
A Priori ◽  
Strong Motion ◽  
Seismic Hazard Assessment ◽  
Seismic Source ◽  
Site Effect ◽  
Source Inversion ◽  
Waveform Data ◽  
Novel Approach ◽  
Spatio Temporal

&lt;p&gt;The seismic source spatio-temporal rupture processes of events in Japan, Greece and Turkey are imaged by backprojection of strong-motion waveforms. Normalized high-frequency (&gt; 2Hz) S-waveforms from recordings on dense strong-motion networks are used to scan a predefined 3D source volume over time.&amp;#160;&lt;/p&gt;&lt;p&gt;Backprojection is an alternative novel approach to image the spatio-temporal earthquake rupture. The method was first applied for large earthquakes at teleseismic distances, but is nowadays also used at local distances and over higher frequencies. The greatest advantage of the method is that processing is done without any a-priori constraints on the geometry, or size of the source. Thus, the spatio-temporal imaging of the rupture is feasible at higher frequencies (&gt; 1Hz) than conventional source inversion studies, even when the examined fault geometry is complex. This high-frequency energy emitted during an earthquake is of great importance in seismic hazard assessment for certain critical infrastructures. The actual challenge in using high-frequency local recordings is to distinguish the local site effects from the true earthquake source content - otherwise, mapping the former incorrectly onto the latter limits the resolvability of the method. It is not straightforward to remove the site effect component or even to distinguish good reference stations from amid hard-soil and rock sites. In this study, the advantages and limitations of the method are explored using waveform data from well-recorded events in Japan (Kumamoto Mw7.1, 2016), Turkey (Marmara Mw6.4, 2019) and Greece (Antikythera Mw6.1, 2019). For each event and seismic array the resolution limits of the applied method are explored by performing various synthetic tests.&lt;/p&gt;

Monitoring Seismicity on Mars - the Marsquake Service for InSight

2020 ◽  
Author(s):  
John Clinton ◽  
Domenico Giardini ◽  
Savas Ceylan ◽  
Martin van Driel ◽  
Simon Stähler ◽  
...  
Keyword(s):  
High Frequency ◽  
Body Wave ◽  
A Priori ◽  
Broad Band ◽  
Low Frequency ◽  
Ambient Vibration ◽  
Crustal Layer ◽  
Seismic Waveforms ◽  
Seismic Vibrations ◽  
Back Azimuth

&lt;p&gt;InSight landed on Mars in late November 2018, and the SEIS seismometer package was fully deployed by February 2019. By January 2020, SEIS continues to exceed performance expectations in terms of observed minimum noise. The Marsquake Service (MQS) has been setup to create and curate a seismicity catalogue for Mars over the lifetime of the InSight mission. Seismic waveforms are downloaded daily from the station and are analysed and processed by the MarsQuake Service, with the goal of detecting seismic vibrations not due to local ambient sources. To this end, every precaution is applied to eliminate possible non-seismic sources, such as noise induced by atmospheric phenomena, lander vibrations and orbiter activity. At the date of submission, we have detected 365 events, of different quality and SNR levels. Signal amplitudes remain small and signal can generally only be detected at night. Some events show only low-frequency waves in the 1-10 sec band, others have a high-frequency content up to several Hz, and others have a more broad-band character. A special class of events involves the excitation of a very prominent ambient vibration at 2.4Hz. Despite the scattered nature of the energy, in many cases, distinct phases can be inferred in the waveforms. Body wave character, and back-azimuth, can only be confirmed for 3 broadband events so far.&amp;#160; The MQS approach for determining distances from broadband events identifies phases as mantle P and S-phases and uses an a priori set of several thousand martian models, derived from geophysical, mineralogical and orbital constraints. High frequency events are currently located assuming phases are trapped crustal Pg and Sg and using a simple crustal layer. The MQS works in conjunction with the Mars Structural Service (MSS) on building and adopting updated models. The MQS consists of an international team of seismologists that screen incoming data to identify and characterise any seismicity. In this presentation, we present the MQS, demonstrate how we detect and characterise marsquakes, and describe the challenges we face dealing with the Martian dataset.&lt;/p&gt;

scholarly journals A Bootstrap Method for the Analysis of Physiological Data in Uncontrolled Settings

2019 ◽  
Vol 63 (1) ◽  
pp. 136-140
Author(s):  
Jordan R. Hill ◽  
Barrett S. Caldwell
Keyword(s):  
High Frequency ◽  
Bootstrap Method ◽  
Physiological Responses ◽  
A Priori ◽  
Physiological Data ◽  
Data Sets ◽  
P Values ◽  
Computational Resources ◽  
Analog Study ◽  
Laboratory Task

There are difficulties associated with analyzing physiological data sets, especially those that are collected at high frequency and those obtained from uncontrolled, non-laboratory task settings. Difficulties include the fact that the data are not independent and not always normally distributed. The authors used a bootstrap ANOVA method to analyze physiological responses collected during the performance of field science deployments in a Mars exploration analog study, and to identify differences in the physiological responses by different task performers in different tasks. The method used addressed the dependence and unknown a priori distributions of the data and provided information as to whether or not the collected responses to each task were statistically significant. Despite the fact that the independence and distribution difficulties were addressed, there were still limitations to the method, which include: the reduction of the power of the analysis, the increased computational resources required, and the limitation that the method does not output p-values to support traditional human factors analyses of whether or not statistical differences exist.

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