scholarly journals Preprocessing of unipolar signals acquired by a novel intracardiac mapping system

2016 ◽  
Vol 2 (1) ◽  
pp. 259-262 ◽  
Author(s):  
Salina Huck ◽  
Tobias Oesterlein ◽  
Armin Luik ◽  
Claus Schmitt ◽  
Reza Wakili ◽  
...  
Keyword(s):  
Time Domain ◽  
High Frequency ◽  
Peak Detection ◽  
The Novel ◽  
Spatial Averaging ◽  
Density Mapping ◽  
Mapping System ◽  
Basket Catheter ◽  
Small Electrode

AbstractThe novel high-density mapping system RhythmiaTM Medical (Boston Scientific, Marlborough, USA) allows a fast and automatic acquisition of intracardiac electrograms (EGMs). For recording the ORION mini-basket catheter is used. Due to the small electrode surface, the spatial averaging is smaller than with other commonly used mapping catheters. This results in a higher quality of unipolar signals. However, these are still corrupted by noise such as high frequency interference. Within this project, methods were developed and benchmarked that can be applied to detect and remove these undesired components. An algorithm was implemented to detect and eliminate artificial peaks in the spectrum of the EGM. The filtered signals showed improved quality in time domain. The performance of the spectral peak detection resulted in a median sensitivity of 92.1% and in a median positive predictive value of 91.9%.

scholarly journals WiPP: Workflow for improved Peak Picking for Gas Chromatography-Mass Spectrometry (GC-MS) data

2019 ◽  
Author(s):  
Nico Borgsmüller ◽  
Yoann Gloaguen ◽  
Tobias Opialla ◽  
Eric Blanc ◽  
Emilie Sicard ◽  
...  
Keyword(s):  
Large Scale ◽  
Automated Analysis ◽  
Peak Detection ◽  
Performance Comparison ◽  
Gas Chromatography Mass Spectrometry ◽  
The Novel ◽  
Peak Picking ◽  
Detection Algorithms ◽  
Biological Dataset

AbstractLack of reliable peak detection impedes automated analysis of large scale GC-MS metabolomics datasets. Performance and outcome of individual peak-picking algorithms can differ widely depending on both algorithmic approach and parameters as well as data acquisition method. Comparing and contrasting between algorithms is thus difficult. Here we present a workflow for improved peak picking (WiPP), a parameter optimising, multi-algorithm peak detection for GC-MS metabolomics. WiPP evaluates the quality of detected peaks using a machine learning-based classification scheme based on seven peak classes. The quality information returned by the classifier for each individual peak is merged with results from different peak detection algorithms to create one final high quality peak set for immediate down stream analysis. Medium and low quality peaks are kept for further inspection. By applying WiPP to standard compound mixes and a complex biological dataset we demonstrate that peak detection is improved through the novel way to assign peak quality, an automated parameter optimisation, and results integration across different embedded peak picking algorithms. Furthermore, our approach can provide an impartial performance comparison of different peak picking algorithms. WiPP is freely available on GitHub (https://github.com/bihealth/WiPP) under MIT licence.

scholarly journals Novel Terahertz Nondestructive Method for Measuring the Thickness of Thin Oxide Scale Using Different Hybrid Machine Learning Models

Coatings ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 805
Author(s):  
Zhou Xu ◽  
Dongdong Ye ◽  
Jianjun Chen ◽  
Haiting Zhou
Keyword(s):  
Machine Learning ◽  
Oxide Scale ◽  
Surface Quality ◽  
Time Domain ◽  
Gaussian White Noise ◽  
Machine Learning Algorithms ◽  
Effective Control ◽  
The Novel ◽  
Thin Oxide

Effective control of the thickness of the hot-rolled oxide scale on the surface of the steel strip is very vital to ensure the surface quality of steel products. Hence, terahertz nondestructive technology was proposed to measure the thickness of thin oxide scale. The finite difference time domain (FDTD) numerical simulation method was employed to obtain the terahertz time-domain simulation data of oxide scale with various thickness (0–15 μm). Added Gaussian white noise with a Signal Nosie Reduction (SNR) of 10 dB was used when simulating real test signals, using four wavelet denoising methods to reduce noise and to compare their effectiveness. Two machine learning algorithms were adopted to set up models to achieve this goal, including the classical back-propagation (BP) neural network algorithm and the novel extreme learning machine (ELM) algorithm. The principal component analysis (PCA) algorithm and particle swarm optimization (PSO) algorithm were combined to reduce the dimensions of the terahertz time-domain data and improve the robustness of the machine learning model. It could be clearly seen that the novel hybrid PCA-PSO-ELM model possessed excellent prediction performance. Finally, this work proposed a novel, convenient, online, nondestructive, noncontact, safety and high-precision thin oxide scale thickness measuring method that could be employed to improve the surface quality of iron and steel products.

Initial single centre experience with the novel Rhythmia© high density mapping system in an all comer collective of 400 electrophysiological patients

2018 ◽  
Vol 272 ◽  
pp. 168-174 ◽  
Author(s):  
Korbinian Lackermair ◽  
Stefanie Kellner ◽  
Antonia Kellnar ◽  
Lisa M. Riesinger ◽  
Reza Wakili ◽  
...  
Keyword(s):  
High Density ◽  
The Novel ◽  
Single Centre ◽  
Density Mapping ◽  
Mapping System ◽  
Single Centre Experience

Simulation of vibration piercing of pipe blank at press

2020 ◽  
Vol 76 (11) ◽  
pp. 1128-1138
Author(s):  
S. R. Rakhmanov
Keyword(s):  
High Frequency ◽  
Deformation Zone ◽  
Pipe Blank ◽  
Equipment Operation ◽  
Metal Deformation ◽  
Technological Tool ◽  
High Frequency Vibrations ◽  
Pipe Blanks ◽  
Wave Phenomena

In some cases, the processes of piercing or expanding pipe blanks involve the use of high-frequency active vibrations. However, due to insufficient knowledge, these processes are not widely used in the practice of seamless pipes production. In particular, the problems of increasing the efficiency of the processes of piercing or expanding a pipe blank at a piercing press using high-frequency vibrations are being solved without proper research and, as a rule, by experiments. The elaboration of modern technological processes for the production of seamless pipes using high-frequency vibrations is directly related to the choice of rational modes of metal deformation and the prediction resistance indicators of technological tools and the reliability of equipment operation. The creation of a mathematical model of the process of vibrating piercing (expansion) of an axisymmetric pipe blank at a piercing press of a pipe press facility is an actual task. A calculation scheme for the process of piercing a pipe plank has been elaborated. A dependence was obtained characterizing the speed of front of plastic deformation propagation on the speed of penetration of a vibrated axisymmetric mandrel into the pipe workpiece being pierced. The dynamic characteristics of the occurrence of wave phenomena in the metal being pierced under the influence of a vibrated tool have been determined, which significantly complements the previously known ideas about the stress-strain state of the metal in the deformation zone. The deformation fields in the zones of the disturbed region of the deformation zone were established, taking into account the high-frequency vibrations of the technological tool. It has been established that the choice of rational parameters (amplitude-frequency characteristics) of the vibration piercing process of a pipe blank results in significant increase in the efficiency of the process, the durability of the technological tool and the quality of the pierced blanks.

Dynamics of the processes in metal machining

1998 ◽  
Vol 2 ◽  
pp. 115-122
Author(s):  
Donatas Švitra ◽  
Jolanta Janutėnienė
Keyword(s):  
High Frequency ◽  
Machine Tools ◽  
Metal Cutting ◽  
Cutting Tool ◽  
Low Frequency ◽  
Metal Cutting Machine ◽  
Cutting Machine ◽  
Metal Machining

In the practice of processing of metals by cutting it is necessary to overcome the vibration of the cutting tool, the processed detail and units of the machine tool. These vibrations in many cases are an obstacle to increase the productivity and quality of treatment of details on metal-cutting machine tools. Vibration at cutting of metals is a very diverse phenomenon due to both it’s nature and the form of oscillatory motion. The most general classification of vibrations at cutting is a division them into forced vibration and autovibrations. The most difficult to remove and poorly investigated are the autovibrations, i.e. vibrations arising at the absence of external periodic forces. The autovibrations, stipulated by the process of cutting on metalcutting machine are of two types: the low-frequency autovibrations and high-frequency autovibrations. When the low-frequency autovibration there appear, the cutting process ought to be terminated and the cause of the vibrations eliminated. Otherwise, there is a danger of a break of both machine and tool. In the case of high-frequency vibration the machine operates apparently quiently, but the processed surface feature small-sized roughness. The frequency of autovibrations can reach 5000 Hz and more.

JOINT INTERPRETATION OF AIRBORNE ELECTROMAGNETIC DATA IN THE TIME DOMAIN AND FREQUENCY DOMAIN

2018 ◽  
Vol 12 (7-8) ◽  
pp. 76-83
Author(s):  
E. V. KARSHAKOV ◽  
J. MOILANEN
Keyword(s):  
Fourier Transform ◽  
Frequency Domain ◽  
Time Domain ◽  
Frequency Interval ◽  
Single Spectrum ◽  
Simultaneous Inversion ◽  
Homogeneous Half Space ◽  
Time Domain Data ◽  
The Time Domain

Тhe advantage of combine processing of frequency domain and time domain data provided by the EQUATOR system is discussed. The heliborne complex has a towed transmitter, and, raised above it on the same cable a towed receiver. The excitation signal contains both pulsed and harmonic components. In fact, there are two independent transmitters operate in the system: one of them is a normal pulsed domain transmitter, with a half-sinusoidal pulse and a small "cut" on the falling edge, and the other one is a classical frequency domain transmitter at several specially selected frequencies. The received signal is first processed to a direct Fourier transform with high Q-factor detection at all significant frequencies. After that, in the spectral region, operations of converting the spectra of two sounding signals to a single spectrum of an ideal transmitter are performed. Than we do an inverse Fourier transform and return to the time domain. The detection of spectral components is done at a frequency band of several Hz, the receiver has the ability to perfectly suppress all sorts of extra-band noise. The detection bandwidth is several dozen times less the frequency interval between the harmonics, it turns out thatto achieve the same measurement quality of ground response without using out-of-band suppression you need several dozen times higher moment of airborne transmitting system. The data obtained from the model of a homogeneous half-space, a two-layered model, and a model of a horizontally layered medium is considered. A time-domain data makes it easier to detect a conductor in a relative insulator at greater depths. The data in the frequency domain gives more detailed information about subsurface. These conclusions are illustrated by the example of processing the survey data of the Republic of Rwanda in 2017. The simultaneous inversion of data in frequency domain and time domain can significantly improve the quality of interpretation.

ДИАГНОСТИКА ХРОНИЧЕСКИХ ИНДУЦИРОВАННЫХ КРАПИВНИЦ

2019 ◽  
pp. 5-13
Author(s):  
E.Yu. Borzova
Keyword(s):  
Quality Of Life ◽  
Biological Therapy ◽  
Treatment Algorithm ◽  
The Novel ◽  
International Guidelines ◽  
Systemic Reactions ◽  
Significant Impairment ◽  
Challenge Tests

Хронические индуцированные крапивницы имеют важное социальноэкономическое значение вследствие риска развития системных реакций и значительного снижения качества жизни пациентов. Диагностика хронических индуцированных крапивниц основывается на анамнестических данных и проведении провокационных тестов. Современный протокол ведения больных хронической крапивницей включает применение неседативных антигистаминных препаратов. Международные согласительные документы по лечению крапивницы рекомендуют 4кратное увеличение суточной дозы неседативных антигистаминных препаратов при их неэффективности в стандартных дозах. Данные метаанализа указывают на эффективность омализумаба при хронических индуцированных крапивницах. В перспективе ожидается расширение арсенала генноинженерной биологической терапии хронических индуцированных крапивниц.Chronic inducible urticarias are characterized by the risks of systemic reactions and a significant impairment of patients quality of life. The diagnosis of chronic inducible urticarias relies on the patients history and the challenge tests. A treatment algorithm for the management of chronic inducible urticarias includes nonsedating antihistamines as a firstline treatment. The international guidelines for the management of chronic inducible urticarias recommend updosing of nonsedating antihistamines up to four fold if standard doses are not effective. The metaanalysis suggests the efficacy of omalizumab in chronic inducible urticarias. In the prospect, the novel options of biological therapy for chronic inducible urticarias are expected.

ДИАГНОСТИКА ХРОНИЧЕСКИХ ИНДУЦИРОВАННЫХ КРАПИВНИЦ

2019 ◽  
Author(s):  
E.Yu. Borzova
Keyword(s):  
Biological Therapy ◽  
Meta Analysis ◽  
Treatment Algorithm ◽  
The Novel ◽  
First Line ◽  
Systemic Reactions ◽  
Significant Impairment ◽  
Challenge Tests ◽  
First Line Treatment

Хронические индуцированные крапивницы имеют важное социально-экономическое значение вследствие риска развития системных реакций и значительного снижения качества жизни пациентов. Диагностика хронических индуцированных крапивниц основывается на анамнестических данных и проведении провокационных тестов. Современный протокол ведения больных хронической крапивницей включает применение неседативных антигистаминных препаратов. Международные согласительные документы по лечению крапивницы рекомендуют 4-кратное увеличение суточной дозы неседативных антигистаминных препаратов при их неэффективности в стандартных дозах. Данные мета-анализа указывают на эффективность омализумаба при хронических индуцированных крапивницах. В перспективе ожидается расширение арсенала генно-инженерной биологической терапии хронических индуцированных крапивниц.Chronic inducible urticarias are characterized by the risks of systemic reactions and a significant impairment of patients quality of life. The diagnosis of chronic inducible urticarias relies on the patients history and the challenge tests. A treatment algorithm for the management of chronic inducible urticarias includes nonsedating antihistamines as a first-line treatment. The international guidelines for the management of chronic inducible urticarias recommend updosing of nonsedating antihistamines up to four fold if standard doses are not effective. The meta-analysis suggests the efficacy of omalizumab in chronic inducible urticarias. In the prospect, the novel options of biological therapy for chronic inducible urticarias are expected.

Systematic literature review of clinical outcomes in adults with metastatic or advanced synovial sarcoma

2020 ◽  
Vol 16 (35) ◽  
pp. 2997-3013
Author(s):  
Kentaro Kogushi ◽  
Michael LoPresti ◽  
Shunya Ikeda
Keyword(s):  
Synovial Sarcoma ◽  
High Frequency ◽  
Clinical Evidence ◽  
Systemic Treatment ◽  
Progression Free Survival ◽  
Treatment Modalities ◽  
Free Survival ◽  
New Treatment ◽  
Poor Outcomes

Background: Synovial sarcoma (SS) is a rare, aggressive soft tissue sarcoma with a poor prognosis after metastasis. The objective of this study was to conduct a systematic review of the clinical evidence for therapeutic options for adults with metastatic or advanced SS. Materials & methods: Relevant databases were searched with predefined keywords. Results: Thirty-nine publications reported clinical data for systemic treatment and other interventions. Data on survival outcomes varied but were generally poor (progression-free survival: 1.0–7.7 months; overall survival: 6.7–29.2 months) for adults with metastatic and advanced SS. A high frequency of neutropenia with systemic treatment and low quality of life post-progression were reported. Conclusion: Reported evidence suggests poor outcomes in adults with metastatic and advanced SS and the need for the development of new treatment modalities.

scholarly journals How Good Is the STW Sensor? An Account from a Larger Shipping Company

2021 ◽  
Vol 9 (5) ◽  
pp. 465
Author(s):  
Angelos Ikonomakis ◽  
Ulrik Dam Nielsen ◽  
Klaus Kähler Holst ◽  
Jesper Dietz ◽  
Roberto Galeazzi
Keyword(s):  
High Frequency ◽  
Additional Data ◽  
Empirical Method ◽  
Influential Factor ◽  
Sensor Data ◽  
Sea State ◽  
Shipping Company ◽  
Frequency Sensor ◽  
Semi Empirical

This paper examines the statistical properties and the quality of the speed through water (STW) measurement based on data extracted from almost 200 container ships of Maersk Line’s fleet for 3 years of operation. The analysis uses high-frequency sensor data along with additional data sources derived from external providers. The interest of the study has its background in the accuracy of STW measurement as the most important parameter in the assessment of a ship’s performance analysis. The paper contains a thorough analysis of the measurements assumed to be related with the STW error, along with a descriptive decomposition of the main variables by sea region including sea state, vessel class, vessel IMO number and manufacturer of the speed-log installed in each ship. The paper suggests a semi-empirical method using a threshold to identify potential error in a ship’s STW measurement. The study revealed that the sea region is the most influential factor for the STW accuracy and that 26% of the ships of the dataset’s fleet warrant further investigation.

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