Enhancement of first arrivals using the τ-p transform on energy-ratio seismic shot records

Geophysics ◽  
2012 ◽  
Vol 77 (3) ◽  
pp. V101-V111 ◽  
Author(s):  
Wail A. Mousa ◽  
Abdullatif A. Al-Shuhail
Keyword(s):  
Conventional Method ◽  
Noise Level ◽  
Energy Ratio ◽  
Data Sets ◽  
Robust Method ◽  
Noise Levels ◽  
High Noise ◽  
Seismic Records ◽  
Better Than

We propose a robust method of first-break picking for data sets with high noise levels through the use of the [Formula: see text] transform on energy-ratio seismic records. Using synthetic shot records with various noise levels, we showed that the performance of this proposed method enhances first arrivals, which helps in picking them. This was particularly true when the noise level was high where picking on raw amplitudes completely fails. We also applied the method on two published real shot records, for which first-break picking was difficult. We showed that for one of the shot records our method succeeds in determining first breaks that are consistent with manual picks and better than those obtained from a conventional method. The method can be used to guide better the subsequent careful picking of first arrivals and requires one forward and one inverse [Formula: see text] transform operations. In contrast to methods based on trace-by-trace picking that often fail to pick some traces, the proposed method automatically interpolates missing picks.

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 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).

SOME EXPERIMENTS ON MULTIPLE REFLECTION CANCELLATION

Geophysics ◽  
1965 ◽  
Vol 30 (6) ◽  
pp. 1085-1093 ◽  
Author(s):  
Daniel Silverman ◽  
N. R. Sparks
Keyword(s):  
Noise Level ◽  
Multiple Reflection ◽  
Multiple Reflections ◽  
Near Surface ◽  
High Noise ◽  
Precise Information ◽  
High Noise Level ◽  
The Earth ◽  
Primary Signal ◽  
Seismic Records

One of the most promising methods of identification or cancellation of multiple reflections on seismic records involves the calculation of synthetic records with all primaries and multiples, and the matching of the synthetic record with the field record. Such matching suffers today from the lack of precise information about the velocities and densities of the formations, dips of beds nonvertical transmission, etc. One possibility of improving this match involves the use of the earth itself as the “synthetic record computer.” In this process, the upcoming (or downgoing) primary signals are fed back into the earth with a vibrator in proper amplitude and phase to create a synthetic record of multiples only, which should match the multiples on the field record. Of course, only those multiple reflections which include a downward reflection from beds above the primary signal detectors will be included in the synthetic record of multiples only. The paper reports two experimental programs. One was carried out on an analog network to simulate the near‐surface and deeper formations, with means to feed back the upcoming signals in proper timing and polarity to cancel the multiples. These experiments indicated the theoretical workability of the process. The second program of experiments involved the use of a vertical spread to detect the upcoming and downgoing signals, and the use of a hydraulic vibrator to impress those signals back into the earth. These experiments were not conclusive because of insufficient power in the vibrator and high noise level. However, they indicated possible ways in which these limitations might be reduced, and the method applied to routine field operations.

scholarly journals NOISE ESTIMATION BY USE OF NEIGHBORING DISTANCES IN TAKENS SPACE AND ITS APPLICATIONS TO STOCK MARKET DATA

2006 ◽  
Vol 16 (06) ◽  
pp. 1865-1869 ◽  
Author(s):  
KRZYSZTOF URBANOWICZ ◽  
JANUSZ A. HOŁYST
Keyword(s):  
Stock Market ◽  
Noise Level ◽  
Chaotic Systems ◽  
Nearest Neighbors ◽  
Noise Estimation ◽  
Noise Levels ◽  
High Noise ◽  
Market Data

We present a method that uses distances between nearest neighbors in Takens space to evaluate a level of noise. The method is valid even for high noise levels. The method has been verified by estimation of noise levels in several chaotic systems. We have analyzed the noise level for Dow Jones and DAX indexes and we have found that the noise level ranges from 25 to 80% of the signal variance.

scholarly journals Noise Descriptors For Kota Metropolis, Rajasthan (India)

2021 ◽  
Vol 16 (1) ◽  
pp. 176-189
Author(s):  
Kuldeep Kuldeep ◽  
Sohil Sisodiya ◽  
Dr. Anil K. Mathur
Keyword(s):  
Noise Level ◽  
Noise Exposure ◽  
Noise Pollution ◽  
Pollution Level ◽  
Exposure Index ◽  
Noise Levels ◽  
Rapid Urbanization ◽  
High Noise ◽  
Sampling Locations ◽  
The City

The most common environmental concern in metropolitan cities worldwide is noise pollution. Kota metropolis (India) is also suffering from the problem of the increased noise level in the urban environment. Kota metropolis has been selected for the assessment of noise pollution. The main reasons behind the increasing level of noise in the city are increased population, rapid urbanization and industrialization, increased transportation facilities, urban development, construction and demolition works etc. The noise levels were recorded for day-time (6 am to 10 pm) as per Indian standard time for 96 days. Sixteen sampling points are made within the city depending upon the category of area/zone such as industrial, residential, silence and commercial. Six days were prescribed for each sampling location for noise level measurement. Noise descriptors such as Lmax, Lmin, L10, L50, L90, NC (noise climate), Lnp (noise pollution level), Leq (equivalent noise level), and NEI (noise exposure index) were computed with the observed data. Noise descriptors are very useful to indicate the physiological and psychological effects of noise pollution associated with noise levels. It makes regulating agency to take necessary actions in high noise areas for noise vulnerable groups such as Childs, old persons etc. Noise levels were recorded with the digital sound level meter " HTC SL-1350". Obtained equivalent noise levels were in between 65 dB(A) to 85 dB(A). The results were then compared with the WHO standards of community noise levels, and Indian noise pollution standards. It is noticed that the noise levels in all monitoring stations were well above the limits of the standards prescribed by the WHO and CPCB. Small variations in noise levels were observed for all sampling locations i.e. noise levels were almost similar at sampling locations. Noise levels were distinct in magnitude for morning and evenings hours. Noise Exposure Index (NEI) was greater than 1 which shows significant high noise levels in all the sampling locations. Kota metropolis desperately needs new strategies to reduces the high noise level in the city. Regulating agencies should take necessary action before things get out of control. Some immediate actions are suggested in the study.

scholarly journals Level of noise pollution at different locations in Tangail municipal area, Bangladesh

2014 ◽  
Vol 26 (1-2) ◽  
pp. 29-36 ◽  
Author(s):  
MMM Hoque ◽  
LK Basak ◽  
M Rokanuzzaman ◽  
Sajal Roy
Keyword(s):  
Noise Level ◽  
Noise Pollution ◽  
Heart Beat ◽  
Motor Vehicles ◽  
Noise Levels ◽  
High Noise ◽  
High Noise Level ◽  
The Road ◽  
Common Problems ◽  
Hospital Shopping

The study was carried out to ascertain the level of noise pollution at different locations in Tangail municipal area. For this purpose noise levels were measured at different locations at different periods of the day. At all the locations the level of noise were found to be higher than the acceptable level. The intensity of noise was found lower with increasing distance from the road side. The noise level on the main road near hospital, shopping center and bazars was above the standard level recommended by MoEF. From the survey motor vehicles were found as the main cause of high noise level. The most common problems with high noise level were found to increased heart beat, drowsiness, headache and hearing impairment. DOI: http://dx.doi.org/10.3329/bjsr.v26i1-2.20228 Bangladesh J. Sci. Res. 26(1-2): 29-36, December-2013

Joint inversion of gravity and gravity gradient data: A systematic evaluation

Geophysics ◽  
2021 ◽  
pp. 1-93
Author(s):  
Joseph Capriotti ◽  
Yaoguo Li
Keyword(s):  
Noise Level ◽  
Joint Inversion ◽  
Low Noise ◽  
Systematic Evaluation ◽  
Gravity Gradient ◽  
Gravity Inversion ◽  
Data Sets ◽  
Noise Levels ◽  
Data Set ◽  
Test Range

Gravity and gravity gradiometry measurements are commonly used to map density variations in the subsurface. Gravity measurements can characterize gravitational anomalies at both long and short wavelengths effectively, but the cost of collecting a sufficiently spatially dense survey to characterize the short wavelengths can be prohibitive. Gravity gradient data can be quickly collected with short wavelength information at a low noise level, but have decreasing sensitivity to longer wavelengths. We describe a method to jointly invert gravity and gravity gradient data that takes advantage of the differing frequency contents and noise levels of the two methods to create an improved image of the subsurface. Previous work simply treated the inversion as a multiple component gravity inversion, however this can cause unintended errors in the recovered models because each data set is not guaranteed to be fit within its noise level. Our joint inversion methodology ensures that both the gravity and gravity gradient data sets are fit to within their individual noise levels by incorporating a relative weighting parameter, and we describe how to find that parameter. This method can also be used to create an improved broadband gravity anomaly map that has a reduced noise level at long wavelengths using a joint equivalent source reconstruction. We first build a synthetic model using a Minecraft world editor, that has different wavelength anomalies, and show the improvement with joint inversion. These results are also confirmed using a real world example at the R. J. Smith test range in Kauring, Australia.

scholarly journals ANALISIS TINGKAT KEBISINGAN TERHADAP STANDAR BAKU MUTU TINGKAT KEBISINGAN DI RUMAH SAKIT MESRA KABUPATEN KAMPAR TAHUN 2020

2021 ◽  
Vol 1 (2) ◽  
pp. 111-120
Author(s):  
M Erizal ◽  
Makomulamin Makomulamin
Keyword(s):  
Noise Level ◽  
Qualitative Interviews ◽  
Hospital Staff ◽  
Quality Standard ◽  
Tree Planting ◽  
Noise Levels ◽  
High Noise ◽  
Level Measurement ◽  
A Value ◽  
Noise Measurements

High noise levels in hospitals can contribute to stress and fatigue in hospital staff, reducing the speed of healing of patients. Noise level measurement is in accordance with the existing quality standard in Permenkes No. 7 of 2019 in Mesra Hospital, Kampar Regency, there are several rooms that exceed the predetermined standard values. The purpose of this study was to determine the level of noise against quality standards at Mesra Hospital in Kampar Regency. This type of research is descriptive qualitative. Interviews and observations were conducted to 5 informants through in-depth interviews. The location of the study was conducted at the Mesra Hospital of Kampar Regency in May-July 2020. The results of the study and the measurements made showed that in front of the intimate hospital had a high noise level such as the lobby during the day the measurements were made with 69 dBA results, for the results of corridor measurements / which hall from the measurement results during the day produces a value of 67 dBA, and the results of measurements during the day in the medical record room produces a value of 67 dBA. From observations and interviews with informants it was found that in handling noise levels were inadequate such as the absence of standard operating procedures regarding noise handling, as well as the absence of printouts of noise measurements that had been carried out and also the lack of noise control at the front of the mesra hospital. Still the loud voice of a traffic vehicle inside the lobby was caused by the lack of tree planting in the front of the mesra hospital.

scholarly journals Assessment of noise pollution in Haridwar city of Uttarakhand State, India during Kumbh Mela 2010 and its impact on human health

2010 ◽  
Vol 2 (2) ◽  
pp. 293-295
Author(s):  
S. Madan ◽  
Pallavi Pallavi
Keyword(s):  
Human Health ◽  
Noise Level ◽  
Ambient Noise ◽  
Noise Pollution ◽  
Noise Levels ◽  
High Noise ◽  
Minimum Noise

The present study was carried to investigate the noise level at four different locations of Haridwar viz. Singh Dwar, Rishikul, Chandi ghat and Har Ki Pauri during Kumbh Mela 2010. During normal days maximum noise levels were recorded at Chandi ghat i.e. 87.11±0.45 dB (A) in the evening hours and minimum noise levels were recorded at Har Ki Pauri i.e. 60.8±0.89 dB (A) in the morning hours. While during festival days maximum noise levels were at Har Ki Pauri i.e. 88.4 ± 1.65 dB (A) in the evening respectively and Rishikul the least being 54.93±0.53 dB (A) in the morning hours. Noise levels in all the areas were found to be above the ambient noise standard. These high noise levels may have induced headache, annoyance, lack of concentration and other varied effects on human health.

scholarly journals Assessment of noise pollution at various locations of Gorakhpur

2021 ◽  
Vol 13 (1) ◽  
pp. 131-137
Author(s):  
Maharshi Yadav ◽  
Ratnesh Kumar Patel ◽  
Abhishek Yadav ◽  
Gaurav Sharma ◽  
Govind Pandey
Keyword(s):  
Human Activities ◽  
Noise Level ◽  
Traffic Noise ◽  
Noise Pollution ◽  
Low Noise ◽  
Educational Institutions ◽  
Noise Levels ◽  
High Noise ◽  
High Noise Level ◽  
Medical College

Noise pollution is one of the major concerns in big cities as well as in the crowded area of small cites, Gorakhpur is fastgrowing city and has many locations with high noise levels. Various crossroads and intersections have traffic issues this causes high noise level. In this study, three locations were selected for noise level assessment, nearby areas of Gorakhnath Temple, BRD medical college and MMMUT. These locations are educational (silent) and low noise level zone but because they situated near traffic roads, which cause high noise levels around them. In this study outside periphery of educational institutions noise level increases due to traffic. Noise level is found to be high due to large number of human activities.  

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