PENGARUH CELAH CAMSHAFT TERHADAP NOISE PADA CYLINDER HEAD HONDA CB 150 R

2022 ◽  
Vol 8 (2) ◽  
pp. 295-301
Author(s):  
Indra Hasan ◽  
Denur
Keyword(s):  
Noise Level ◽  
Cylinder Head ◽  
Ride Comfort ◽  
Noise Levels ◽  
Space And Time ◽  
A Value

Noise on a motorcycle is unwanted sound because it does not fit the context of space and time thus affecting ride comfort . Noise caused by the vibrating object or objects collide . Which became the main object causes of noise in the Cylinder Head Honda cb 150 R is due to the large gap camshaft causing collision between the camshaft with holder. This research was conducted entirely in the workshop by examining the influence of several variations of the gap camshaft to noise generated in the cylinder head . Variations slit used was 0,75 mm , 0,85 mm , 0,95 mm , 1,05 mm, and 1,15 mm . The results showed that the variation of the gap camshaft significant effect on the noise generated , namely : a gap of 0,75 mm camshaft generate noise by 78,12 dB , 0,85 mm gap camshaft generate noise with a value of 78,37 dB , 0,95 mm gap camshaft generate noise 78,93 dB , 1,05 mm gap camshaft generate noise levels at 79,95 dB, and 1,15 mm gap camshafts produce 80,23 dB. Based on the results of the research with camshaft gap variation can be concluded that the lowest noise level generated by the camshaft gap of 0,75 mm .

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 Noise in Otolaryngology – Head and Neck Surgery operating rooms: a systematic review

2021 ◽  
Vol 50 (1) ◽  
Author(s):  
Gianluca Sampieri ◽  
Amirpouyan Namavarian ◽  
Marc Levin ◽  
Justine Philteos ◽  
Jong Wook Lee ◽  
...  
Keyword(s):  
Systematic Review ◽  
Head And Neck ◽  
Patient Outcomes ◽  
Noise Level ◽  
Neck Surgery ◽  
Operating Rooms ◽  
Head And Neck Surgery ◽  
Noise Levels ◽  
Surgical Performance ◽  
The Mean

Abstract Objective Noise in operating rooms (OR) can have negative effects on both patients and surgical care workers. Noise can also impact surgical performance, team communication, and patient outcomes. Such implications of noise have been studied in orthopedics, neurosurgery, and urology. High noise levels have also been demonstrated in Otolaryngology-Head and Neck Surgery (OHNS) procedures. Despite this, no previous study has amalgamated the data on noise across all OHNS ORs to determine how much noise is present during OHNS surgeries. This study aims to review all the literature on noise associated with OHNS ORs and procedures. Methods Ovid Medline, EMBASE Classic, Pubmed, SCOPUS and Cochrane databases were searched following PRISMA guidelines. Data was collected on noise measurement location and surgery type. Descriptive results and statistical analysis were completed using Stata. Results This search identified 2914 articles. Final inclusion consisted of 22 studies. The majority of articles analyzed noise level exposures during mastoid surgery (18/22, 82%). The maximum noise level across all OHNS ORs and OHNS cadaver studies were 95.5 a-weighted decibels (dBA) and 106.6 c-weighted decibels (dBC), respectively (P = 0.2068). The mean noise level across all studies was significantly higher in OHNS cadaver labs (96.9 dBA) compared to OHNS ORs (70.1 dBA) (P = 0.0038). When analyzed together, the mean noise levels were 84.9 dBA. Conclusions This systematic review demonstrates that noise exposure in OHNS surgery exceeds safety thresholds. Further research is needed to understand how noise may affect team communication, surgical performance and patient outcomes in OHNS ORs. Graphical abstract

Effective splicing localization based on noise level inconsistencies

2021 ◽  
pp. 1-11
Author(s):  
P. N. R. L. Chandra Sekhar Author ◽  
T. N. Shankar Author
Keyword(s):  
Digital Technology ◽  
Social Networking Sites ◽  
Noise Level ◽  
Research Work ◽  
Multimedia Content ◽  
Noise Levels ◽  
Multimedia Forensics ◽  
The Past ◽  
Photo Editing ◽  
State Of Art

In the era of digital technology, it becomes easy to share photographs and videos using smartphones and social networking sites to their loved ones. On the other hand, many photo editing tools evolved to make it effortless to alter multimedia content. It makes people accustomed to modifying their photographs or videos either for fun or extracting attention from others. This altering brings a questionable validity and integrity to the kind of multimedia content shared over the internet when used as evidence in Journalism and Court of Law. In multimedia forensics, intense research work is underway over the past two decades to bring trustworthiness to the multimedia content. This paper proposes an efficient way of identifying the manipulated region based on Noise Level inconsistencies of spliced mage. The spliced image segmented into irregular objects and extracts the noise features in both pixel and residual domains. The manipulated region is then exposed based on the cosine similarity of noise levels among pairs of individual objects. The experimental results reveal the effectiveness of the proposed method over other state-of-art methods.

scholarly journals Characterization of Noise Level Inside a Vehicle under Different Conditions

Sensors ◽  
2020 ◽  
Vol 20 (9) ◽  
pp. 2471 ◽  
Author(s):  
Daniel Flor ◽  
Danilo Pena ◽  
Luan Pena ◽  
Vicente A. de Sousa ◽  
Allan Martins
Keyword(s):  
Regression Analysis ◽  
Noise Level ◽  
Acoustic Noise ◽  
Experimental Setup ◽  
Strongly Correlated ◽  
Noise Levels ◽  
Noise Sources ◽  
Statistical Tools ◽  
Window Position

Vehicular acoustic noise evaluations are a concern of researchers due to health and comfort effects on humans and are fundamental for anyone interested in mitigating audio noise. This paper focuses on the evaluation of the noise level inside a vehicle by using statistical tools. First, an experimental setup was developed with microphones and a microcomputer located strategically on the car’s panel, and measurements were carried out with different conditions such as car window position, rain, traffic, and car speed. Regression analysis was performed to evaluate the similarity of the noise level from those conditions. Thus, we were able to discuss the relevance of the variables that contribute to the noise level inside a car. Finally, our results revealed that the car speed is strongly correlated to interior noise levels, suggesting the most relevant noise sources are in the vehicle itself.

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.

The variability of naturally occurring magnetic field levels: 10 Hz to 8 kHz

Geophysics ◽  
2010 ◽  
Vol 75 (6) ◽  
pp. F187-F197 ◽  
Author(s):  
Ben K. Sternberg
Keyword(s):  
Magnetic Field ◽  
Noise Level ◽  
Monsoon Season ◽  
Signal Frequency ◽  
Time Interval ◽  
Frequency Range ◽  
Noise Levels ◽  
Controlled Source ◽  
Naturally Occurring ◽  
Minimum Noise

The variability of naturally occurring magnetic fields in the frequency range from [Formula: see text] over a period of one year was studied. Contour plots for the [Formula: see text], [Formula: see text], and [Formula: see text] components and for frequencies of 10, 100, 1000, 2000, and 8000 Hz were produced. Average, minimum, maximum, and the standard deviations of these fields were also calculated for 12 distinctive time intervals. In the 1– to 8–kHz frequency range, the noise levels are typically higher at night. In the 10- to 100-Hz frequency range, the noise levels are typically higher during the day. During mid- to late-summer, there is frequent thunderstorm activity, known in the southwest United States as the monsoon season. The magnetic field levels are often very high during this time period. These variability ranges can be used to estimate the lowest levels of noise that may be encountered during field surveys, which iswhat the authors are looking for when running controlled-source electrical method surveys. These variability ranges can also be used to estimate the highest levels that may be encountered, which is what the authors are looking for when running natural-source electrical methods surveys, such as audio frequency magnetotelluric (AMT) surveys. These measurements of magnetic field strength variability show that better data for controlled-source electrical measurements can be obtained using the minimum noise level measurements, as opposed to using signal integration or signal averaging with all of the data. The minimum noise level is found by using frequency bins adjacent to the signal-frequency bin. Likewise, if one is interested in measuring the naturally occurring magnetic field data, using the maximum values during each time interval makes AMT measurements possible when the natural signal level is very low, particularly in the AMT dead zone around [Formula: see text].

scholarly journals ON IMPROVEMENT OF ENVIRONMENTAL INDICATORS OF THE KHARKIV MOTORWAY SECTION

2021 ◽  
Vol 6 (166) ◽  
pp. 196-203
Author(s):  
E. Lezhneva ◽  
I. Lynnyk ◽  
K. Vakulenko ◽  
N. Sokolova
Keyword(s):  
Noise Level ◽  
Internal Combustion Engines ◽  
Road Transport ◽  
Environmental Indicators ◽  
Sound Waves ◽  
Solar Panels ◽  
Residential Areas ◽  
Noise Levels ◽  
Large Cities ◽  
Main Area

Nowadays, on the territory of large cities, there is an increase in emissions of harmful substances into the atmosphere. The reasons for this are manifold: violation of design technological regimes, outdated equipment, an increase in the volume of road transport. The constantly growing intensity of traffic flows is annually accompanied by an increase in the anthropogenic load on the population of modern cities. With the increase in the number of vehicles on the streets of large cities, the world community has identified noise as one of the main factors that worsen the standard of living of people. To assess the noise pollution of the environment by road transport, a typical area of the urban area in the Kharkiv micro district was chosen. The study consisted of four main stages: Stage I – assessment of the road condition and environmental situation in the courtyards of the micro district; Stage II – assessment of acoustic pollution of the main area; Stage III – assessment of the concentration of pollutants; Stage IV – measures to reduce the level of environmental hazard. The study revealed that residential areas around Gagarin Avenue are prone to high noise levels and high concentrations of pollutants in the air. So, Gagarin Avenue is in the zone of acoustic discomfort (noise level 80 dBA), which exceeds the permissible noise level, while the degree of man-made impact on the environment during road operation is 1000 UAH / hour for every 100 people. Based on the results of calculations of the concentrations of pollutants from vehicles along Gagarin Avenue, it was found that for almost all substances their concentrations exceed the MPC by more than 3 times. Analysis of the experience of European countries in the use of noise protection screens with integrated solar panels allowed us to propose a model of noise protection barrier with integrated solar panels, which can be used to protect the urban environment from noise, sound waves and exhaust chemicals. gases from internal combustion engines. It has been established that the placement of a combined noise protection screen will reduce the noise level by about 8–15 dBA. Noise load maps were built in the main area before and after the implementation of the environmental measure. The results of the study will make it possible to introduce administrative and legislative measures to ensure regulatory noise levels for residential areas adjacent to highways and environmental safety when organizing traffic on the streets of large cities.

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).

Noise Levels: A database of industrial noise level measurements

Online Review ◽  
1988 ◽  
Vol 12 (4) ◽  
pp. 211-217 ◽  
Author(s):  
J. Robert ◽  
B.P. Pathak
Keyword(s):  
Noise Level ◽  
Noise Levels ◽  
Industrial Noise

The Influence of the Exit Velocity Profile on the Noise of a Jet

1954 ◽  
Vol 4 (4) ◽  
pp. 341-360 ◽  
Author(s):  
Alan Powell
Keyword(s):  
Velocity Profile ◽  
Noise Level ◽  
Turbulent Pipe Flow ◽  
Aerodynamic Noise ◽  
Noise Levels ◽  
Flow Forming ◽  
Flow Velocity Profile ◽  
Jet Velocity ◽  
Initial Turbulence ◽  
Moving Fluid

SummaryThe noise levels of a jet issuing from a long pipe are compared with those of a jet having a square velocity profile at the exit. A subsonic noise reduction of between 2 and 5 decibels for various conditions is found for the case of the flow emerging with an approximately “turbulent pipe-flow” velocity profile for the same maximum jet velocity, but this is at the expense of a loss in thrust of a quarter. On comparison with a jet of smaller diameter which has an equal thrust for the same maximum jet velocity, it is found that the changes in noise level are rather smaller. For jets of equal diameters, the effects on the subsonic aerodynamic noise generated of a reduction of velocity gradient near the boundary are more than offset by the increased velocities necessary near the centre of the jet to obtain equal thrust. It is concluded that if the effect of differences in initial turbulence can be neglected the use of an auxiliary flow forming a comparatively thin sheath of slower moving fluid at the exit is not likely to result in large decreases in the subsonic noise level, and that a general reduction in jet velocity is more effective.Above the critical pressure larger reductions of up to 10 decibels are found. These are consistent with a delay of the onset of the self-maintained shock-produced noise.

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