Measurement of Noise inside the Compartment and Vibration on both Sides of Elastomeric Powertrain Mounts of Passenger Car

2013 ◽  
Vol 471 ◽  
pp. 59-63
Author(s):  
Mohd Noor Arib Rejab ◽  
Roslan Abd Rahman ◽  
Raja Ishak Raja Hamzah ◽  
Jawaid Iqbal Inayat Hussain ◽  
Nazirah Ahmad ◽  
...  

This paper presents an evaluation on elastomeric mount used to isolate vibration from powertrain to chassis or structure vehicle. The assessments started with measurement of noise inside compartment, and exhaust noise. This is followed by the measurement of vibration on both sides of elastomeric mounts. The noise in the compartment and exhaust noise is measured according to BS 6086: 1981 and BS ISO 5130: 2007. The noise in the compartment and vibration is tested in three conditions. Firstly, engine is run-up with load (driving at second gear); secondly, without load; and thirdly, without load but hanging. A microphone is fixed at the ear of the mannequin. The fast response and A weighting sound level meter were used for measurement noise in the compartment and exhaust noise. The vibration is measured in terms of acceleration on both sides of each elastomeric powertrain mounts. Two accelerometer transducers are fixed on both sides of powertrain elastomeric mounts. One side was identified as a source of vibration and the other as receiver of vibrations. The results showed that the pattern of overall vibration level on source and receiver increased from 1050 RPM (idling) to 4000 RPM on all test conditions. Vibration transmitted to chassis or receiver structure was analyzed using transmissibility concept. By evaluating test condition of engine run-up without load, informed that the front and rear mounts showed a high level transmissibility contributing to structure-borne noise.

2013 ◽  
Vol 27 (3) ◽  
pp. 545-563
Author(s):  
Josip Glaurdić

Could the Western foreign policy makers have done anything to prevent the violence accompanying the breakup of Yugoslavia? The answer to that question largely depends on their level of awareness of what was happening in the South Slavic federation in the run-up to war. This article analyzes a string of newly declassified documents of the British Foreign Office related to the February 1991 visit of a high-level British political delegation to Yugoslavia, together with interviews with some of the meetings’ protagonists. These declassified documents and interviews offer a unique snapshot in the development of the Yugoslav crisis and Britain’s policy in the region. They give us a clear picture of the goals and strategies of the principal Yugoslav players and show us what the West knew about the true nature of the Yugoslav crisis and when. The article’s conclusions are clear. Yugoslavia’s breakup and impending violence did not require great foresight. Their cause was known well in advance because it was preannounced—it was the plan of the Serbian regime of Slobodan Milošević to impose a centralized Yugoslavia upon the other republics or, if that failed, to use force to create a Greater Serbia on Yugoslavia’s ruins. Crucially, British policy at the time did nothing to dissuade Milošević from his plan and likely contributed to his confidence in using violence to pursue the creation of a new and enlarged Serbian state.


2021 ◽  
Vol 6 (2) ◽  
pp. 106-111
Author(s):  
Herdi Susanto ◽  
Kamarullah

The purpose of this study was to analyze the level of vibration and noise on the Equipment Vibrating screen crusher FC 02 at PT. MIFA Bersaudara. Vibration is measured using a vibration meter, noise is measured by a digital sound level meter. Measurements are made on the x, y and z axes at each measurement point. The results showed that the value of the vibration level on the Vibrating screen crusher FC 02 on the x-axis with the velocity value of 28.56 mm/s, the y-axis value of 29.82 mm/s and the z-axis velocity value of 25.46 mm/s. While the Acceleration value on the x-axis is 20.7 m/s 2 the value is 30.86 m/s 2on the y and z axes of 21.42 m/s 2 . While the noise value indicates that the average value on the right side is 99.6 dBA on the right side and 101.7 dBA on the left side. Efforts were made to overcome the problem, namely by not operating the VSC FC 02 exceeding the recommended maximum limit of 60 dBA and the maximum allowed which is 70 dBA so as to prevent problems of comfort, health, and safety at work. Operators and employees are advised to stay at the location for no more than 15-30 minutes, if more than that time must use safety earmuffs.


2013 ◽  
Vol 44 (2s) ◽  
Author(s):  
Pietro Catania ◽  
Mariangela Vallone

Noise in agriculture is one of the risk factors to be taken into account in the assessment of the health and safety of workers; in particular, it is known that the tractor is a source of high noise. The Italian Low Decree 81/2008 defined the requirements for assessing and managing noise risk identifying a number of procedures to be adopted at different noise levels to limit workers exposure. This paper concerns the analysis of the noise risk arising from the use of a tracklaying tractor during field operations carried out in the vineyard. The objective of this study was to evaluate the noise level that comes close to the ear of the operator driving the tractor measuring the values of equivalent sound level (Leq(A)) and peak sound pressure (LCpk). We considered four options related to the same tractor coupled with the following tools to perform some farming operations: rototilling, chisel plough, flail mowers and vibro farmer. We considered three test conditions: T1 in flat (slope 0%), T2 uphill and T3 downhill (both 30% slope). The instrument used for the measurements is a precision integrating portable sound level meter, class 1, model HD2110L by Delta OHM, Italy. Each survey lasted 2 minutes, with an interval of measurement equal to 0.5 s. The tests were performed in compliance with the standards ISO 9612 and ISO 9432. The results show that the measured sound levels exceed the limits allowed by the regulations in almost all the test conditions; values exceeding the threshold limit of 80 dB(A) were recorded coming up to a maximum value of 92.8 dB(A) for flail mowers in test T1. When limits imposed by the regulations are exceeded, the operator is obliged to wear the appropriate Personal Protective Equipment.


2015 ◽  
Vol 5 ◽  
pp. 69-74
Author(s):  
Lakshmi Nath Bhattarai

Undesirable sound for human hearing is called as noise. It was measured at the selected locations of silent, residential and commercial zones of Siddharthanagar Municipality by using Dick Smith Digital Sound Level Meter Q 1362 for ‘A’ weighting in day time at 9:00 AM to 6:00 PM in the month of November and December 2012. The result shows that at each location the Leq noise levels are above than the noise level standard prescribed by Government of Nepal and WHO. Maximum Leq of 81.9 dB(A) was observed at the Bus park of commercial area and minimum 54.5 dB(A) was observed at Medical College area of silent zone. In other places, the Leq lie in the range 56.2 dB(A) to 81.9 dB(A). The study showed that the places lying along highways have high level of noise which is due to bad condition of roads, vehicles and unnecessary use of horns  The Himalayan Physics Vol. 5, No. 5, Nov. 2014 Page: 69-74


1970 ◽  
Vol 1 (2) ◽  
pp. 34-36
Author(s):  
Mehedi Imam

In Bangladesh, demand for judicial independence in practice has been a much debated issue and the demand is fulfilled but expectation of people is not only limited to have an independent judiciary but to have an impartial system and cadre of people, which will administer justice rationally being free from fear or force. The independence of judiciary and the impartial judicial practice are related concepts, one cannot sustain without the other and here existence as well as the need of practicing impartiality is well recognized. But the art of practicing impartiality does not develop overnight as it’s related to development of one’s attitude. It takes a considerable time resulting from understanding, appreciating and acknowledging the moral values, ethics and professional responsibility. The judiciary includes Judges, Advocates mostly who are expected to demonstrate a high level of moral values and impartiality towards people seeking justice and ‘rule of law’. This is true that bench officers and clerks are also part of the process to ensure rule of law with same level of participation by the law enforcing agencies such as police. However the paper includes only those who either join judiciary as Judge/Magistrate or Advocate to explore level and extent of ethical knowledge they receive being key role players of the system. DOI: http://dx.doi.org/10.3329/bioethics.v1i2.9628 Bangladesh Journal of Bioethics 2010; 1(2): 34-36


Climate justice requires sharing the burdens and benefits of climate change and its resolution equitably and fairly. It brings together justice between generations and justice within generations. The United Nations Sustainable Development Goals summit in September 2015, and the Conference of Parties to the Framework Convention on Climate Change in Paris in December 2015, brought climate justice center stage in global discussions. In the run up to Paris, Mary Robinson, former president of Ireland and the UN Secretary General’s Special Envoy for Climate Change, instituted the Climate Justice Dialogue. The editors of this volume, an economist and a philosopher, served on the High Level Advisory Committee of the Climate Justice Dialogue. They noted the overlap and mutual enforcement between the economic and philosophical discourses on climate justice. But they also noted the great need for these strands to come together to support the public and policy discourse. This volume is the result.


Water ◽  
2021 ◽  
Vol 13 (12) ◽  
pp. 1682
Author(s):  
Yoonja Kang ◽  
Yeongji Oh

The interactive roles of zooplankton grazing (top-down) and nutrient (bottom-up) processes on phytoplankton distribution in a temperate estuary were investigated via dilution and nutrient addition experiments. The responses of size-fractionated phytoplankton and major phytoplankton groups, as determined by flow cytometry, were examined in association with zooplankton grazing and nutrient availability. The summer bloom was attributed to nanoplankton, and microplankton was largely responsible for the winter bloom, whereas the picoplankton biomass was relatively consistent throughout the sampling periods, except for the fall. The nutrient addition experiments illustrated that nanoplankton responded more quickly to phosphate than the other groups in the summer, whereas microplankton had a faster response to most nutrients in the winter. The dilution experiments ascribed that the grazing mortality rates of eukaryotes were low compared to those of the other groups, whereas autotrophic cyanobacteria were more palatable to zooplankton than cryptophytes and eukaryotes. Our experimental results indicate that efficient escape from zooplankton grazing and fast response to nutrient availability synergistically caused the microplankton to bloom in the winter, whereas the bottom-up process (i.e., the phosphate effect) largely governed the nanoplankton bloom in the summer.


Nanophotonics ◽  
2020 ◽  
Vol 9 (10) ◽  
pp. 3271-3278 ◽  
Author(s):  
Qian Ma ◽  
Qiao Ru Hong ◽  
Xin Xin Gao ◽  
Hong Bo Jing ◽  
Che Liu ◽  
...  

AbstractFor the intelligence of metamaterials, the -sensing mechanism and programmable reaction units are two important components for self-recognition and -determination. However, their realization still face great challenges. Here, we propose a smart sensing metasurface to achieve self-defined functions in the framework of digital coding metamaterials. A sensing unit that can simultaneously process the sensing channel and realize phase-programmable capability is designed by integrating radio frequency (RF) power detector and PIN diodes. Four sensing units distributed on the metasurface aperture can detect the microwave incidences in the x- and y-polarizations, while the other elements can modulate the reflected phase patterns under the control of a field programmable gate array (FPGA). To validate the performance, three schemes containing six coding patterns are presented and simulated, after which two of them are measured, showing good agreements with designs. We envision that this work may motivate studies on smart metamaterials with high-level recognition and manipulation.


2016 ◽  
Vol 34 (1) ◽  
pp. 54-76
Author(s):  
Sebastian Jäckle

This paper explores the determinants of ministerial duration within the German Länder between 1990 and 2010. In arguing that different terminal events ceasing ministerial tenures should be analyzed separately, it distinguishes four exit types: voluntary, forced, collective (ministers leaving office because their whole party does so) and exits that are neither volitional acts of the minister nor politically induced. Depending on the exit type, competing-risks Cox-models show different effects for one and the same variable on the hazard for ministerial turnover. Seniority in high-level politics for example helps not to be forced out of office while it has no effect on voluntary or collective exits. Heading an important ministry on the other hand increases the chances to rise to other positions in high politics or private business, but does not impact the other two hazards. The analysis furthermore shows that the principal-agent-logic known from Westminster systems with the prime minister being largely sovereign in hiring and firing cabinet members must be adapted to the German context of frequent coalition governments. In coalition governments, only ministers from the same party as the prime minister exhibit higher hazards for forced exits, while ministers from other coalition partners are much safer in that regard.


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