Signal enhancement in the presence of high noise levels—the electrocardiogram

1996 ◽  
Vol 34 (7) ◽  
pp. 418-419 ◽  
Author(s):  
Corissa Thompson ◽  
Arne Troelstra
Keyword(s):  
Signal Enhancement ◽  
Noise Levels ◽  
High Noise

The physical environment

2018 ◽  
Author(s):  
Philip James
Keyword(s):  
Physical Environment ◽  
Urban Climate ◽  
Urban Environments ◽  
Artificial Light ◽  
Noise Levels ◽  
Light At Night ◽  
High Noise ◽  
P Elements ◽  
Micro Organisms ◽  
Diversity Of Life

Elements of the physical aspects of urban environments determine which micro-organisms, plants, and animals live in urban environments. In this chapter, climate, air, water, soil, noise, and light are discussed. Urban environments are affected by the climate of the region in which they are located, and in turn and create their own, distinctive urban climate. Air, water, and soil are all affected by urbanization. Pollution of these elements is common. High noise levels and artificial light at night (ALAN—a new phenomenon) are both strongly associated with urban environments. Details of both are discussed. The discussion in this chapter provides a foundation for further exploration of the diversity of life in urban environments and for later exploration of how organisms adapt to urban living, which will be discussed in Parts II and III.

Improved Vancouver Raman Algorithm Based on Empirical Mode Decomposition for Denoising Biological Samples

2019 ◽  
Vol 73 (12) ◽  
pp. 1436-1450 ◽  
Author(s):  
Fabiola León-Bejarano ◽  
Martin O. Méndez ◽  
Miguel G. Ramírez-Elías ◽  
Alfonso Alba
Keyword(s):  
Empirical Mode Decomposition ◽  
Raman Spectra ◽  
Biological Samples ◽  
Biological Material ◽  
Noise Levels ◽  
Synthetic Material ◽  
High Noise ◽  
Mode Decomposition ◽  
Mean Filter ◽  
The Mean

A novel method based on the Vancouver Raman algorithm (VRA) and empirical mode decomposition (EMD) for denoising Raman spectra of biological samples is presented. The VRA is one of the most used methods for denoising Raman spectroscopy and is composed of two main steps: signal filtering and polynomial fitting. However, the signal filtering step consists in a simple mean filter that could eliminate spectrum peaks with small intensities or merge relatively close spectrum peaks into one single peak. Thus, the result is often sensitive to the order of the mean filter, so the user must choose it carefully to obtain the expected result; this introduces subjectivity in the process. To overcome these disadvantages, we propose a new algorithm, namely the modified-VRA (mVRA) with the following improvements: (1) to replace the mean filter step by EMD as an adaptive parameter-free signal processing method; and (2) to automate the selection of polynomial degree. The denoising capabilities of VRA, EMD, and mVRA were compared in Raman spectra of artificial data based on Teflon material, synthetic material obtained from vitamin E and paracetamol, and biological material of human nails and mouse brain. The correlation coefficient (ρ) was used to compare the performance of the methods. For the artificial Raman spectra, the denoised signal obtained by mVRA ([Formula: see text]) outperforms VRA ([Formula: see text]) for moderate to high noise levels whereas mVRA outperformed EMD ([Formula: see text]) for high noise levels. On the other hand, when it comes to modeling the underlying fluorescence signal of the samples (i.e., the baseline trend), the proposed method mVRA showed consistent results ([Formula: see text]. For Raman spectra of synthetic material, good performance of the three methods ([Formula: see text] for VRA, [Formula: see text] for EMD, and [Formula: see text] for mVRA) was obtained. Finally, in the biological material, mVRA and VRA showed similar results ([Formula: see text] for VRA, [Formula: see text] for EMD, and [Formula: see text] for mVRA); however, mVRA retains valuable information corresponding to relevant Raman peaks with small amplitude. Thus, the application of EMD as a filter in the VRA method provides a good alternative for denoising biological Raman spectra, since the information of the Raman peaks is conserved and parameter tuning is not required. Simultaneously, EMD allows the baseline correction to be automated.

Noise Pollution in Onitsha Metropolis: Challenges and Solution

2021 ◽  
Vol 1 (2) ◽  
pp. 032-040
Author(s):  
Chris Onyeka Ekweozor ◽  
Johnbosco Emeka Umunnakwe ◽  
Leo O Osuji ◽  
Vincent C Weli
Keyword(s):  
State Government ◽  
Noise Level ◽  
Control Point ◽  
Noise Pollution ◽  
Health Impact ◽  
Dry Season ◽  
Noise Levels ◽  
Wet Season ◽  
High Noise ◽  
Anambra State

This study evaluated noise pollution in Onitsha metropolis, Anambra State, Nigeria in 2019. Noise levels were measured at forty sampling stations in the morning, afternoon and night within the study area for dry and wet seasons using modern noise level instruments. A control point was established at ldeani/Nnobi Junction with coordinates N 06o 05’.282’’ E 006o 55’.891’’ which was used as a reference point and for comparison with the sound levels recorded in designated locations. The results showed that the maximum noise level in the study area exceeded the Federal Ministry of Environment (FMEnv) limit by 7.8% in the dry season and by 13.11% in the wet season. Noise LAeq exceeded the NESREA LAeq limit by 29.89% in the dry season and by 33.44% in the wet season. The study indicated that the mean noise levels in the dry and wet seasons were within FMEnv limit of 90dB .It also showed that high noise levels were recorded around major junctions and market places within Onitsha, which are harmful to public health. The study further showed that transportation activities and trading activities at the market places are the main sources of high noise levels in the study area. Health impact assessment should be conducted in Onitsha metropolis for residents. State government should enforce compliance laws and regulate the activities of industries in the areas.

scholarly journals The sound of potency: An observation study of nurses’ approach to sound in a pediatric intensive care unit

2017 ◽  
Vol 5 (2) ◽  
pp. 46
Author(s):  
Emma Mellgren ◽  
Janet Mattsson
Keyword(s):  
Intensive Care Unit ◽  
Intensive Care ◽  
Pediatric Intensive Care Unit ◽  
Pediatric Intensive Care ◽  
Well Being ◽  
High Tech ◽  
Noise Levels ◽  
Observation Study ◽  
Care Environment ◽  
High Noise

Objective: The objective of this study was to investigate the nurses’ approach to three sources of sound that contribute to high noise levels; alarms, doors that open and conversation.Methods: Methods used derived from a theoretical perspective based on interpretive phenomenology and caring culture. In the pediatric intensive care, the caregivers of the children work in a high-tech environment as they are surrounded by sound from several sources. How caregivers understand and acknowledge how these sounds negatively affect a child’s well-being depends on their individual knowledge and awareness of how children are affected by sound. In most cases, coming into an intensive care unit is a new experience for a child. This causes greater stress, both from the environment itself as well as from sound levels. The method was built on a phenomenological perspective and an interpretive non-participation, semi-structured observations were conducted in a pediatric intensive care unit (PICU) of one of Sweden’s metropolitan regions in the winter of 2014-2015.Results: The results show that noise is an overlooked phenomenon in the pediatric intensive care environment as it has given way to other priorities in the nurse’s work. It is also apparent that this depends on the department’s caring culture as it prioritizes other things, resulting in normalizing high levels of noise as a part of the pediatric intensive care environment.Conclusions: Noise levels are not a priority in the department’s caring culture. High noise levels are permitted unreflectedly and appears to be a token of potency and an accepted part of the health care environment.

S254 – Bone Conduction Noise Exposure via Ventilators in the NICU

2008 ◽  
Vol 139 (2_suppl) ◽  
pp. P160-P160
Author(s):  
Angela P Black ◽  
James D Sidman
Keyword(s):  
Ambient Noise ◽  
Noise Exposure ◽  
Bone Conduction ◽  
Sound Level ◽  
Noise Levels ◽  
High Noise ◽  
Endotracheal Tubes ◽  
Level Meter ◽  
Hearing Damage ◽  
Air Conduction

Objectives To demonstrate that neonatal ventilators produce high noise levels through bone conduction (BC) via endotracheal tubes, as well as air conduction (AC) from ambient noise. Methods A sound level meter was used to measure the noise levels 4 feet from the ventilator and in direct contact at the end of a balloon attached to the ETT to simulate the noise presented to the infant. 3 commonly used neonatal ventilators (Sensormedics 3100A, VIP Bird and Bunnell Jet) were examined. Results Noise levels were significantly higher (6 – 14 dB) at the end of the ETT than 4 ft from the ventilator for all ventilators studied. Conclusions Previous studies have shown high ambient noise levels in NICUs, but have failed to address the actual noise presented to the infant. ETT transmission of noise as a direct bone stimulus through the skull has been overlooked. This study has shown that high noise intensities are being presented not only as AC, but as BC to the infants though the ETT. This study demonstrates, therefore, that ear protection alone will not save these at-risk infants from hearing damage. More must be done to decrease noise exposure and develop quieter machines.

Seismic signal recovery in the presence of high noise levels

2010 ◽  
Author(s):  
Alejandro D. Alcudia ◽  
Ruben D. Martinez
Keyword(s):  
Seismic Signal ◽  
Signal Recovery ◽  
Noise Levels ◽  
High Noise

scholarly journals Identifying high noise levels with possible health implications at building façades for five crossroads in Tirana, Albania

2018 ◽  
Author(s):  
Kuenda Laze
Keyword(s):  
Questionnaire Data ◽  
Noise Levels ◽  
High Noise ◽  
Geographical Data ◽  
Health Implications ◽  
Building Facades

There are geographical and questionnaire data. Questionnaire data were paper-based data. Geographical data were mainly provided by Openstreemap (www.openstreemap.org).

scholarly journals Appraisal of Noise Level Dissemination Surrounding Mining and Industrial Areas of Keonjhar, Odisha: a Comprehensive Approach Using Noise Mapping

2017 ◽  
Vol 42 (3) ◽  
pp. 423-432 ◽  
Author(s):  
Satish K. Lokhande ◽  
Satyajeet A. Dhawale ◽  
Samir S. Pathak ◽  
Rakesh Gautam ◽  
Mohindra C. Jain ◽  
...  
Keyword(s):  
Noise Level ◽  
Sound Level ◽  
Noise Levels ◽  
Night Time ◽  
Noise Mapping ◽  
High Noise ◽  
Sensitive Areas ◽  
Sound Levels ◽  
Directorate General ◽  
Open Cast

Abstract Noise mapping is a well-established practice among the European nations, and it has been follow for almost two decades. Recently, as per guidelines of the Directorate General of Mines Safety (DGMS), India, noise mapping has been made mandatory in the mining expanses. This study is an effort to map the noise levels in nearby areas of mines in the northern Keonjhar district. The motive of this study is to quantify the existing A-weighted time-average sound level (LAeq,T ) in the study area to probe its effects on the human dwellings and noise sensitive areas with the probability of future development of the mines, roads, and industrial and commercial zone. The LAeq,T was measured at 39 identified locations, including industrial, commercial, residential, and sensitive zones, 15 open cast mines, 3 major highways, and 3 haulage roads. With the utilisation of Predictor LimA Software and other GIS tools, the worked out data is mapped and noise contours are developed for the visualisation and identification of the extent and distribution of sound levels across the study area. This investigation discloses that the present noise level at 60% of the locations in silence and residential zone exposed to significantly high noise levels surpasses the prescribed limit of Central Pollution Control Board (CPCB), India. The observed day and night time LAeq, T level of both zones ranged between 43.2-62.2 dB(A) and 30.5-53.4 dB(A), respectively, whereas, the average Ldn values vary between 32.7 and 51.2 dB(A). The extensive mobility of heavy vehicles adjoining the sensitive areas and a nearby plethora of open cast mines is the leading cause of exceeded noise levels. The study divulges that the delicate establishments like schools and hospitals are susceptible to high noise levels throughout the day and night. A correlation between observed and software predicted values gives R2 of 0.605 for Ld, 0.217 for Ln, and 0.524 for Ldn. Finally, the mitigation measure is proposed and demonstrated using a contour map showing a significant reduction in the noise levels by 0-5.3 dB(A).

scholarly journals Road Noise Levels in Urban Environment Compared to Specification Limits. The Case of the City of Larissa, Greece

2020 ◽  
Author(s):  
Emmanouil A. Papadimitriou ◽  
Grigorios P. Papageorgiou ◽  
Nikolaos Alamanis ◽  
Theodosia-Niki Diakosavva
Keyword(s):  
Road Traffic ◽  
Traffic Noise ◽  
Road Traffic Noise ◽  
Noise Levels ◽  
Road Noise ◽  
Greek City ◽  
Limit Values ◽  
High Noise ◽  
Specification Limits ◽  
The City

Greece, as well as other developed countries, is facing the growing problem of road traffic noise. It stands for a severe problem in the urban areas of the country, including the city of Larissa. The root cause is the huge increase in traffic volume and the lack of adequate urban infrastructure planning. Estimation of the level of road traffic noise is usually conducted using acoustic meters. It is widely accepted that most of the cities’ population is exposed to high noise levels due to controversial traffic capacity. Moreover, high noise levels are strongly related to phycological and neurological diseases. Thus, it is of utmost importance, the road noise levels to be lower than dictated by relevant specification limits. To develop better noise-environment policies, relative research should focus on the measurement of in-situ noise levels, so as appropriate for each case corrective measures to be taken. The present paper examines the noise levels of a center road of the 5th Greek city, in terms of population, compared to worldwide adopted noise specification limits. The clear aim stands for finding the percentage of road noise that exceeds commonly accepted threshold values, namely limit values of European Union and World Health Organization. The results of this research strongly indicate that measured noise values override upper limit values in a certain extent.

Design solutions to mitigate high noise levels on small fishing vessels

2021 ◽  
Vol 172 ◽  
pp. 107632 ◽  
Author(s):  
Giorgio Burella ◽  
Lorenzo Moro
Keyword(s):  
Noise Levels ◽  
High Noise ◽  
Fishing Vessels ◽  
Design Solutions
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