A Study on Noise in Synchronous Belt Drives (Experimental and Theoretical Analysis of Impact Sound)

2003 ◽  
Vol 125 (4) ◽  
pp. 773-778 ◽  
Author(s):  
Weiming Zhang ◽  
Tomio Koyama
Keyword(s):  
Theoretical Analysis ◽  
Transverse Vibration ◽  
Acoustic Energy ◽  
Generation Mechanism ◽  
The Other ◽  
Belt Drives ◽  
Analytical Results ◽  
Belt Width ◽  
The Impact

There are two kinds of noise in synchronous belt drives. One is steady sound caused by transverse vibration of the belt, and the other is impact sound radiating from the meshing point of the belt and pulley. In this study, a theoretical analysis is provided to prove the generation mechanism of the impact sound and discuss factors that influence the level of sound. Comparison between experimental and analytical results is carried out. It is concluded that the level of impact sound is in proportion to the belt width, and the acoustic energy of impact sound is in proportion to the cube of the belt width.

A Study on Noise in Synchronous Belt Drives: Experimental and Theoretical Analysis of Impact Sound

2000 ◽  
Author(s):  
Weiming Zhang ◽  
Tomio Koyama
Keyword(s):  
Theoretical Analysis ◽  
Natural Frequency ◽  
Sound Source ◽  
Transverse Vibration ◽  
Sound Field ◽  
Acoustic Energy ◽  
Generation Mechanism ◽  
Belt Drives ◽  
Fundamental Natural Frequency ◽  
The Impact

Abstract There are two kinds of noise in synchronous belt drives. One is steady sound caused by transverse vibration of belt, and another is impact sound radiating from meshing point of belt and pulley. Recently, it has been reported that the impact sound is due to the sound occurring in an air pipe built up between pulley groove and belt because the frequency of impact sound coincides with the fundamental natural frequency of an open ended pipe whose length equals width of the belt. However, this conclusion is obtained experimentally, there has no theoretical analysis provided. In this study, an analysis of the impact sound is provided to prove its generation mechanism and discuss factors that influence the level of sound theoretically. Sound field in an open ended pipe subjected to an impulsive sound source is analyzed. Comparison between experimental and analytical results is carried out. It is concluded that the level of impact sound is in proportion to the width of belt, and the acoustic energy of impact sound is in proportion to the cube of the width of belt.

Transmission Error Due to Resonance in Synchronous Belt Drive With Eccentric Pulley

2017 ◽  
Vol 139 (12) ◽  
Author(s):  
Masanori Kagotani ◽  
Hiroyuki Ueda
Keyword(s):  
Transverse Vibration ◽  
Rotation Frequency ◽  
Transmission Error ◽  
The Other ◽  
Belt Drive ◽  
Integer Multiple ◽  
Belt Drives ◽  
Eccentric Shaft ◽  
Synchronous Belt Drive ◽  
Frequency Variations

In synchronous belt drives, it is generally difficult to eliminate pulley eccentricity, because the pulley teeth and shaft hole are produced separately and the pulley is installed on an eccentric shaft. This eccentricity affects the accuracy of rotation transmission, so that the belt tension changes during a single rotation of the pulley. This in turn affects the occurrence of resonance in the spans. In the present study, the transmission error in a synchronous belt drive with an eccentric pulley in the absence of a transmitted load was experimentally investigated for the case in which the spans undergo first-mode transverse vibration due to resonance. The transmission error was found to have a component with a period equal to the span displacement, in addition to a component with a period of half the span displacement. During a single rotation of the pulley, the magnitude of the transmission error increased, and its frequency decreased, with decreasing belt tension. The transmission error exhibited the large value when two frequency conditions were satisfied: one was that the meshing frequency was within the range of span frequency variations due to the eccentricity, and the other was that the minimum span frequency was close to an integer multiple of the pulley rotation frequency. Even if both of these conditions occurred, if the range of span frequency variations due to the eccentricity was larger than 13 Hz, the transmission error could be eliminated by adjusting the belt tension, so that the average span frequency corresponded to the meshing frequency.

scholarly journals Using digital technologies in refereeing to correctly identify the winner in judo competitions

2021 ◽  
pp. 98-106
Author(s):  
M. Chobotko ◽  
I. Chobotko
Keyword(s):  
Theoretical Analysis ◽  
Digital Technology ◽  
Video Recording ◽  
Digital Technologies ◽  
The Other ◽  
The Internet ◽  
Significant Difference ◽  
The Impact ◽  
Final Block

Purpose: to analyze the impact of the use of digital technology in judging to correctly identify the winner in judo competitions. Material and methods. The following methods were used during the research: theoretical analysis and generalization of literature sources and data of the Internet, analysis of video recording, methods of mathematical statistics. Results: based on the recordings of 42 fights of the final block of the European Championship and the Ukrainian Junior Judo Championship on video hosting (You Tube), the analysis of the impact of video replays on the referee's decision was conducted to correctly identify the winner in the competition. In 22 bouts of the European Championship and in 24 bouts of the Ukrainian Championship, the referees made decisions that did not require revision or change. In the other 20 fights of the European Championship and in 18 fights of the Ukrainian Championship, video replays were used. A comparison of the average rates of fights in which digital replays were used or not used with the help of digital technologies showed a statistically significant difference in the performance of refereeing at the European Championship and the Ukrainian Judo Championship among juniors (<0,05). Since t (0,051) < tgr (1,98) the analysis of the refereeing of the European Championship and the Ukrainian Junior Judo Championship can be considered statistically significant. As a percentage of the total number of 42 fights, of which 20 fights – 47,6 % of international judges use video replays and 22 fights – 52,3 % of international judges did not use video replays. Analyzing the championship of Ukraine with a total of 42 fights, of which 18 fights – 42,8 % of judges use video replays and 24 fights – 57,1 % of judges did not use video replays. Conclusions. Analysis of existing digital technologies used in judo refereeing has revealed a set of programs that assist in the competition. The use of digital technologies provides an opportunity to improve the quality of refereeing at various ranks of the competition. The percentage of using video views and the percentage without video views at the European Championship and the Ukrainian Championship is almost the same. This speaks to the quality of judging at these events. This is because the refereeing of the final block allows more qualified judges who did not make mistakes during the refereeing or these mistakes were minimal. Keywords: judo, digital technologies, video replays, YouTube, European Championship, Ukrainian Championship, judges.

The Effect of Geometry Imperfections on the Performance of Multiple V-Belt Drives

1989 ◽  
Vol 111 (1) ◽  
pp. 153-159 ◽  
Author(s):  
G. Massouros
Keyword(s):  
Power Transmission ◽  
Mean Value ◽  
The Other ◽  
Belt Drive ◽  
Transmitted Power ◽  
Belt Drives ◽  
Analytical Results ◽  
Analytical Relations

It has been observed in practice, that the lifetime of a multiple V-belt drive is always less than the corresponding life of a single V-belt drive. This is due to an uneven contribution of all belts of the multiple drive to the power transmission owing to microerrors in the equality of the diameters and profiles of all grooves and of the lengths of all belts. These microerrors cause a distribution of the transmission ratios among the branches of the V-belt around a mean value which in turn results in an uneven loading of the belts and a reduction of their “life.” In the present work, analytical relations are obtained for the influence of the aforementioned errors on the elastic creep of the belts, on the transmitted power, and on the other characteristics of the belt drive. An experiment was made to verify the analytical results.

Modernism, Empiricism, and Rationalism

2016 ◽  
Vol 46 (1) ◽  
pp. 38-47
Author(s):  
Geoffrey Squires
Keyword(s):  
Twentieth Century ◽  
The Other ◽  
Modern Poetry ◽  
Philosophical Perspective ◽  
Irish Poetry ◽  
Dimensional Spectrum ◽  
Culture History ◽  
The World ◽  
The Impact ◽  
Rule Out

Modernism is usually defined historically as the composite movement at the beginning of the twentieth century which led to a radical break with what had gone before in literature and the other arts. Given the problems of the continuing use of the concept to cover subsequent writing, this essay proposes an alternative, philosophical perspective which explores the impact of rationalism (what we bring to the world) on the prevailing empiricism (what we take from the world) of modern poetry, which leads to a concern with consciousness rather than experience. This in turn involves a re-conceptualisation of the lyric or narrative I, of language itself as a phenomenon, and of other poetic themes such as nature, culture, history, and art. Against the background of the dominant empiricism of modern Irish poetry as presented in Crotty's anthology, the essay explores these ideas in terms of a small number of poets who may be considered modernist in various ways. This does not rule out modernist elements in some other poets and the initial distinction between a poetics of experience and one of consciousness is better seen as a multi-dimensional spectrum that requires further, more detailed analysis than is possible here.

HOME VISITS DURING THE FIRST MONTH OF DELIVERY FOR RECENTLY DELIVERED WOMEN IN UTTAR PRADESH, INDIA

2020 ◽  
Vol 6 (5) ◽  
pp. 1183-1189
Author(s):  
Dr. Tridibesh Tripathy ◽  
Dr. Umakant Prusty ◽  
Dr. Chintamani Nayak ◽  
Dr. Rakesh Dwivedi ◽  
Dr. Mohini Gautam
Keyword(s):  
Large Scale ◽  
National Level ◽  
Uttar Pradesh ◽  
Life Time ◽  
Structured Interview ◽  
The Other ◽  
Registration System ◽  
Action Group ◽  
Current Article ◽  
The Impact

The current article of Uttar Pradesh (UP) is about the ASHAs who are the daughters-in-law of a family that resides in the same community that they serve as the grassroots health worker since 2005 when the NRHM was introduced in the Empowered Action Group (EAG) states. UP is one such Empowered Action Group (EAG) state. The current study explores the actual responses of Recently Delivered Women (RDW) on their visits during the first month of their recent delivery. From the catchment area of each of the 250 ASHAs, two RDWs were selected who had a child in the age group of 3 to 6 months during the survey. The response profiles of the RDWs on the post- delivery first month visits are dwelled upon to evolve a picture representing the entire state of UP. The relevance of the study assumes significance as detailed data on the modalities of postnatal visits are available but not exclusively for the first month period of their recent delivery. The details of the post-delivery first month period related visits are not available even in large scale surveys like National Family Health Survey 4 done in 2015-16. The current study gives an insight in to these visits with a five-point approach i.e. type of personnel doing the visit, frequency of the visits, visits done in a particular week from among those four weeks separately for the three visits separately. The current study is basically regarding the summary of this Penta approach for the post- delivery one-month period.     The first month period after each delivery deals with 70% of the time of the postnatal period & the entire neonatal period. Therefore, it does impact the Maternal Mortality Rate & Ratio (MMR) & the Neonatal Mortality Rates (NMR) in India and especially in UP through the unsafe Maternal & Neonatal practices in the first month period after delivery. The current MM Rate of UP is 20.1 & MM Ratio is 216 whereas the MM ratio is 122 in India (SRS, 2019). The Sample Registration System (SRS) report also mentions that the Life Time Risk (LTR) of a woman in pregnancy is 0.7% which is the highest in the nation (SRS, 2019). This means it is very risky to give birth in UP in comparison to other regions in the country (SRS, 2019). This risk is at the peak in the first month period after each delivery. Similarly, the current NMR in India is 23 per 1000 livebirths (UNIGME,2018). As NMR data is not available separately for states, the national level data also hold good for the states and that’s how for the state of UP as well. These mortalities are the impact indicators and such indicators can be reduced through long drawn processes that includes effective and timely visits to RDWs especially in the first month period after delivery. This would help in making their post-natal & neonatal stage safe. This is the area of post-delivery first month visit profile detailing that the current article helps in popping out in relation to the recent delivery of the respondents.   A total of four districts of Uttar Pradesh were selected purposively for the study and the data collection was conducted in the villages of the respective districts with the help of a pre-tested structured interview schedule with both close-ended and open-ended questions.  The current article deals with five close ended questions with options, two for the type of personnel & frequency while the other three are for each of the three visits in the first month after the recent delivery of respondents. In addition, in-depth interviews were also conducted amongst the RDWs and a total 500 respondents had participated in the study.   Among the districts related to this article, the results showed that ASHA was the type of personnel who did the majority of visits in all the four districts. On the other hand, 25-40% of RDWs in all the 4 districts replied that they did not receive any visit within the first month of their recent delivery. Regarding frequency, most of the RDWs in all the 4 districts received 1-2 times visits by ASHAs.   Regarding the first visit, it was found that the ASHAs of Barabanki and Gonda visited less percentage of RDWs in the first week after delivery. Similarly, the second visit revealed that about 1.2% RDWs in Banda district could not recall about the visit. Further on the second visit, the RDWs responded that most of them in 3 districts except Gonda district did receive the second postnatal visit in 7-15 days after their recent delivery. Less than half of RDWs in Barabanki district & just more than half of RDWs in Gonda district received the third visit in 15-21 days period after delivery. For the same period, the majority of RDWs in the rest two districts responded that they had been entertained through a home visit.

Wacana Kolonial dalam Novel Max Havelaar: Sebuah Kajian Poskolonial

Metahumaniora ◽  
2017 ◽  
Vol 7 (3) ◽  
pp. 411
Author(s):  
Abu Bakar Ramadhan Muhamad
Keyword(s):  
Point Of View ◽  
The Other ◽  
The Novel ◽  
Colonial Discourse ◽  
The Impact ◽  
The Voice

AbstrakHegemoni kolonialisme dalam budaya poskolonial merupakan alasan penelitian inikemudian mengkaji wacana kolonial dalam novel Max Havellar (MH) khususnya dampakditimbulkannya. Dampak dimaksud adalah posisi keberpihakan pemikiran tersirat darikarya tersebut. Hasil pembahasan menunjukkan, secara temporal maupun permanen MHmenyuarakan ketidakadilan dalam kondisi-kondisi kolonial menyangkut penindasan sangpenjajah terhadap terjajah. Hanya saja, upaya mengatasnamakan atau mewakili suarakaum terjajah terbukti mengimplikasikan ciri ideologis statis kerangka kolonialisme(orientalisme); yakni cara pandang Eropasentris, di mana “Barat” sebagai self adalah superior,dan “Timur” sebagai other adalah inferior. Dalam konteks poskolonialisme, MH dengan sifatkritisnya yang berupaya “menyuarakan” nasib pribumi terjajah, justru menampilkan stigmapenguatan kolonialitas itu sendiri secara hegemonik. Artinya, “menyuarakan” nasib pribumidimaknai sebagai keberpihankan kolonial yang kontradiktif, di mana stigma penguatankolonialitas justru lebih terasa, ujung-ujungnya melanggengkan hegemoni kolonial. Tidakmembela yang terjajah, tetapi memperhalus cara kerja mesin kolonial.AbstractThe hegemony of colonialism in the culture of postcolonial society is the reason this studythen examines the colonial discourse in the novel Max Havellar (MH) in particular the impactit brings. The impact in question is the implied position of thought in the work. The resultsof the discussion show that, temporarily or permanently, MH voiced injustice in the colonialconditions regarding the oppression of the colonist against the colonized. However, the effort toname or represent the voice of the colonized has proven to imply a static ideological characterin the framework of colonialism (orientalism); ie Eropacentric point of view, in which “West” asself is superior, and “East” as the other is the inferior. In the context of postcolonialism, MH withits critical nature that seeks to “voice” the fate of the colonized natives, actually presents thestigma of strengthening coloniality itself hegemonicly. That is, “voicing” the fate of the pribumiis interpreted as a contradictory colonial flare, where the stigma of strengthening colonialityis more pronounced, which ultimately perpetuates the hegemony of colonialism. No longerdefending the colonized, but refining the workings of the colonial machinery.

Gifted Students' Motivation and its Impact on the Development of their Giftedness

2018 ◽  
Vol 3 (1) ◽  
Author(s):  
Hussein SALEM MUBARAK BARABWD ◽  
Mohammad YUSOFF BIN MOHD NOR ◽  
Noriah Mohd Ishak
Keyword(s):  
Extrinsic Motivation ◽  
Gifted Students ◽  
Qualitative Approach ◽  
The Other ◽  
Phenomenological Method ◽  
Self Confidence ◽  
Verbal Praise ◽  
Intrinsic Motivations ◽  
The Impact ◽  
Intrinsic And Extrinsic Motivations

The aim of the current study is to examine the intrinsic and extrinsic motivations of the gifted students from Hadhramout Gifted Center HGC in Yemen, and to investigate the impact of these intrinsic and extrinsic motivations on their giftedness development. A qualitative approach was adopted; data has been collected through an open- ended questionnaire that was prepared by the researcher and distributed among a sample of gifted students who were chosen purposively from HGC. The interpretative phenomenological method has been used to analyze the data using, Atlas ti. The results indicate that the majority of the participants consider it interesting to explore new things, and experience curiosity and desire to achieve their goals as their intrinsic motivations. Whereas, the minority consider preference to serve the community, competition preference and self-confidence as their intrinsic motivations. On the other hand, half of the participants consider rewards as their extrinsic motivation, whereas 40 % of them consider exams scores, verbal praise, parents and environment as their extrinsic motivations. Regarding the impact of intrinsic and extrinsic motivations on the development of giftedness, the majority of the participants believe that intrinsic and extrinsic motivations affect positively the development of their giftedness development. Finally, based on the findings, some recommendations were provided. 

SCENARIOS FOR AN EXPANDING DEMAND OF TOURISM ON THE COASTS OF CUBA

2017 ◽  
Author(s):  
Oscar Gutiérrez-Bolívar ◽  
Oscar Gutiérrez-Bolívar ◽  
Pedro Fernández Carrasco ◽  
Pedro Fernández Carrasco
Keyword(s):  
United States ◽  
The Other ◽  
Sudden Increase ◽  
Tourist Destination ◽  
Other Hand ◽  
The Usa ◽  
The Impact

The opening of relationships between United States and Cuba could be a drive for a huge increase in the affluence of tourism to Cuba and especially to the coast areas. Cuba has been for many years an important tourist destination for people from many countries, but almost forbidden for US citizens. The proximity of the USA, its amount of population as well as their great acquisition power will increase in a very substantial way the demand for accommodation and other uses in the proximity of the coasts. There will be a need to implement a package of measures that reduce the impact of such sudden increase in the coastal line. On the other hand that augment in tourism could be an opportunity to improve the standard of life of Cubans. The consideration of different possibilities of such development, the analysis of the damages that each one could cause as well as the measures that could avoid, ameliorate or compensate such effects are the goals that are going to be presented in this paper.

Environmental Scanning for Organisational Effectiveness: A Study of Select MSMEs of Jammu and Kashmir, India

2015 ◽  
Vol 4 (3) ◽  
Author(s):  
Vinay Chauhan ◽  
Sushma Kaushal
Keyword(s):  
Organizational Effectiveness ◽  
Business Environment ◽  
Two Dimensions ◽  
The State ◽  
The Other ◽  
Political Environment ◽  
Environmental Scanning ◽  
Jammu And Kashmir ◽  
Economic Dimension ◽  
The Impact

Environmental scanning yields greater anticipatory management that provides important inputs for aquitision and use of information for planning and designing organization strategies. Apart from this, effective environmental scanning activities are likely to deal with threats and grasp the opportunities to finally link with enhancing organizational effectiveness. In fact this relationship matrix has led the researchers to conduct an environmental scanning through an examination of the existing status the components of the macro-environment vis-a-vis their relationship with the organizational effectiveness. There are a number of approaches, which describe the macro-environment, of which PEST analysis is regarded as the most common approach for considering the external business environment. Thus, the present study applies PEST analysis to scan the existing business environment. Jammu and Kashmir due to its peculiar political, geographical, economic, and socio-cultural features, had led its cost mountain economy become a distinctive identity. Despite the fact that the state has rich endowments, international relations with its neighbours vis-a-vis its impact on political environment also pose developmental challenges for the business units operating in the state. This has provided valid rationale for conducting the present. The environmental scanning is done through the perception of the select entrepreneurs operating MSMEs in the state of J & K. An impact analysis of environmental factors (PEST) on the organizational effectiveness is also done in the study. The findings of the study show that the political environment of the state that is not favourable for entrepreneural development whereas the rest of the other drivers of PEST i.e. economic environment, socio-cultural environment, and technological environment show a favourable response of the entrepreneurs. In terms of cause and effect relationship, it is found that the first two drivers of the PEST i.e. political and economic dimension impacts OE positively whereas the other two dimensions namely socio-cultural and technological impacts OE negatively but it is pertinent to mention that the impact is very less and is insigninificant. The study also suggests some of strategic options for developing and creating an enabling environment for successful entrepreneurial development to achieve integrated development of the state.

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