scholarly journals Analysis of the Effects of the Viscous Thermal Losses in the Flute Musical Instruments

2021 ◽  
Vol 5 (1) ◽  
pp. 11
Author(s):  
Gaby Abou Haidar ◽  
Xavier Moreau ◽  
Roy Abi Zeid Daou

This article presents the third part of a larger project whose final objective is to study and analyse the effects of viscous thermal losses in a flute wind musical instrument. After implementing the test bench in the first phase and modelling and validating the dynamic behaviour of the simulator, based on the previously implemented test bench (without considering the losses in the system) in the second phase, this third phase deals with the study of the viscous thermal losses that will be generated within the resonator of the flute. These losses are mainly due to the friction of the air inside the resonator with its boundaries and the changes of the temperature within this medium. They are mainly affected by the flute geometry and the materials used in the fabrication of this instrument. After modelling these losses in the frequency domain, they will be represented using a system approach where the fractional order part is separated from the system’s transfer function. Thus, this representation allows us to study, in a precise way, the influence of the fractional order behaviour on the overall system. Effectively, the fractional behavior only appears much below the 20 Hz audible frequencies, but it explains the influence of this order on the frequency response over the range [20–20,000] Hz. Some simulations will be proposed to show the effects of the fractional order on the system response.

MEDISAINS ◽  
2020 ◽  
Vol 17 (3) ◽  
pp. 67
Author(s):  
Rani Setiyaningsih ◽  
Evi Dwi Utami ◽  
Agus Santosa

Background: Symptoms experienced hemorrhoid sufferers are feeling pain in the anus, especially in sitting position. It is necessary to innovate special underwear which can reduce pressure on the anus and the pain experienced by the patientObjective: the study aimed to create and analyze special underwear for hemorrhoid sufferers which increased comfort and reduce the intensity of pain.Methods: This research imitated Research and Development (R&D. It consisted of 3 stages; stage I (literature study), stage II (product development) and stage III (product experiment).Result: The literature study in stage I obtained materials used to create special underwear for hemorrhoid sufferers by Cotton Combed 30s of 100% premium cotton and foam as a cushion. In the second phase of the research, designs and shapes were obtained. The results of product experiment in the third phase of the study discovered that respondents felt more comfortable by the special underwear than ordinary underwear and it was very effective in reducing pain.Conclusion: The innovation of hemorrhoid underwear is effective to increase comfort and reduce pain intensity in hemorrhoid sufferers.


2013 ◽  
Vol 5 (1) ◽  
Author(s):  
Abdul Hasan Saragih

This classroom research was conducted on the autocad instructions to the first grade of mechinary class of SMK Negeri 1 Stabat aiming at : (1) improving the student’ archievementon autocad instructional to the student of mechinary architecture class of SMK Negeri 1 Stabat, (2) applying Quantum Learning Model to the students of mechinary class of SMK Negeri 1 Stabat, arising the positive response to autocad subject by applying Quantum Learning Model of the students of mechinary class of SMK Negeri 1 Stabat. The result shows that (1) by applying quantum learning model, the students’ achievement improves significantly. The improvement ofthe achievement of the 34 students is very satisfactory; on the first phase, 27 students passed (70.59%), 10 students failed (29.41%). On the second phase 27 students (79.41%) passed and 7 students (20.59%) failed. On the third phase 30 students (88.24%) passed and 4 students (11.76%) failed. The application of quantum learning model in SMK Negeri 1 Stabat proved satisfying. This was visible from the activeness of the students from phase 1 to 3. The activeness average of the students was 74.31% on phase 1,81.35% on phase 2, and 83.63% on phase 3. (3) The application of the quantum learning model on teaching autocad was very positively welcome by the students of mechinary class of SMK Negeri 1 Stabat. On phase 1 the improvement was 81.53% . It improved to 86.15% on phase 3. Therefore, The improvement ofstudent’ response can be categorized good.


2020 ◽  
Author(s):  
Adriana Klein ◽  
Roseli de Deus Lopes ◽  
Rodrigo Suigh

BACKGROUND EasySeating is a mobile health (mHealth) app that supports the prescription of wheelchair and postural support devices (WPSD). It can be used by occupational therapists (OT) and physiotherapists (PT) who prescribe WPSD. The app offers a standardization of the prescription procedure, showing images, metrics and details that guide the prescriber to decide on the best equipment. It was developed with an iterative mixed-methods evaluation approach. Objective: The aim of this study was to investigate the processes involved in the prescription of WPSD and to propose, develop and evaluate a mHealth to support OT and PT prescribers. OBJECTIVE The aim of this study was to investigate the processes involved in the prescription of WPSD and to propose, develop and evaluate a mHealth to support OT and PT prescribers. METHODS This study was divided into three phases and was carried out as an iterative process composed of user consulting/testing (using a mixed-methods evaluation approach), system (re)design and software development. The first phase consisted of the collection of qualitative and quantitative data to map and understand the users requirements and of the development of the first prototype (v1) of the app. This data collection was performed through semi-structured interviews with 14 OT and PT prescribers, 5 specialized technicians and 5 WPSD users. The second phase aimed at improving the overall functionality of the app and consisted in the development, test and evaluation of the prototypes v1, v2, v3 and v4. A total of 59 prescribers tested and evaluated these prototypes by means of open interviews, semi-structured questionnaires and focus groups. The third phase focused in the usability aspects of the app. It consisted in the development and test of the prototype v5. Eight technology specialists assessed its usability through heuristics evaluation. RESULTS Data collected in phase one indicated there is a lack of standardization on the prescription of postural support devices (PSD). A divergent nomenclature for the PSDs was also found and classified in eight categories. These information guided the development of the first prototype of the EasySeating app. Phase two results pointed that the prescribers value the insertion of the app into their clinical practice, as it accelerates and increases the quality of the evaluation process and improves the organization of the prescription information. Significant suggestions for the improvement of the app were given during the users tests, including the use of images to represent the PSDs. The usability tests from the third phase revealed two strong issues that must be solved: the need of greater feedback and failures in the persistence of the input data. CONCLUSIONS This study demonstrated that there is a lack of systematization of the WPSD prescription process. The evaluation of the developed EasySeating app demonstrated that there is a potential to standardize, integrate and organize the WPSD prescription information, supporting and facilitating the decision making process of the prescribers. CLINICALTRIAL This study was approved by the Research Ethics Board of the Universidade de São Paulo (registered protocol n°53929516.6.0000.0065) URL - http://plataformabrasil.saude.gov.br/login.jsf


2019 ◽  
Vol 29 (2) ◽  
pp. 104-125

Three phases in Foucault’s examination of authorship and free speech were essential to him throughout his life. They can be linked to such texts as the three lectures “What is an Author?” (first phase), “What is Critique?,” and “What is Revolution?” (second phase), and the two lecture courses, “Fearless Speech,” and “The Courage of Truth” (third phase). Initially, Foucault merely describes the founders of discursivity (hence, “superauthors”), among whom he reckoned only Marx and Freud, as the sole alternative to his own conceptualization of the author function, which is exhibited en masse in contemporary society. He then modifies his views on superauthorship by making Kant the paradigm and by linking his own concept of free speech to a Kan-tian critical attitude. However, Foucault claims only the half of Kant’s philosophical legacy that is related to the study of the ontology of the self.The article advances the hypothesis that the sovereign power of speech, which can be found in Marx and Heidegger and in generally in the concept of “superauthorship,” becomes unacceptable for Foucault. During the third phase, the danger of a tyrannical use of free speech compels Foucault to make a number of fruitful but questionable choices in his work. He focuses on a single aspect of free speech in which a speaker is in a weaker position and therefore has to overcome his fear in order to tell the truth. Foucault associates this kind of free speech with the ancient Greek notion of parrhesia, which according to his interpretation means “fearless speech”; however, this reading is not always supported by the ancient Greek sources. Foucault’s deliberations bring him to the radical conclusion that free speech transforms into performative “aesthetics of existence.” Foucault’s main motivation for pursuing this line of thought all through his life was to investigate his own abilities and powers as an author


Molecules ◽  
2021 ◽  
Vol 26 (4) ◽  
pp. 1007
Author(s):  
Jiří Gregor ◽  
Kateřina Radilová ◽  
Jiří Brynda ◽  
Jindřich Fanfrlík ◽  
Jan Konvalinka ◽  
...  

Influenza A virus (IAV) encodes a polymerase composed of three subunits: PA, with endonuclease activity, PB1 with polymerase activity and PB2 with host RNA five-prime cap binding site. Their cooperation and stepwise activation include a process called cap-snatching, which is a crucial step in the IAV life cycle. Reproduction of IAV can be blocked by disrupting the interaction between the PB2 domain and the five-prime cap. An inhibitor of this interaction called pimodivir (VX-787) recently entered the third phase of clinical trial; however, several mutations in PB2 that cause resistance to pimodivir were observed. First major mutation, F404Y, causing resistance was identified during preclinical testing, next the mutation M431I was identified in patients during the second phase of clinical trials. The mutation H357N was identified during testing of IAV strains at Centers for Disease Control and Prevention. We set out to provide a structural and thermodynamic analysis of the interactions between cap-binding domain of PB2 wild-type and PB2 variants bearing these mutations and pimodivir. Here we present four crystal structures of PB2-WT, PB2-F404Y, PB2-M431I and PB2-H357N in complex with pimodivir. We have thermodynamically analysed all PB2 variants and proposed the effect of these mutations on thermodynamic parameters of these interactions and pimodivir resistance development. These data will contribute to understanding the effect of these missense mutations to the resistance development and help to design next generation inhibitors.


2021 ◽  
Vol 13 (01) ◽  
pp. 35-41
Author(s):  
Sunyarn Niempoog ◽  
Kiat Witoonchart ◽  
Woraphon Jaroenporn

AbstractModern hand surgery in Thailand started after the end of World War II. It is divided into 4 phases. In the initial phase (1950-1965), the surgery of the hand was mainly performed by general surgeons. In 1965-1975, which was the second phase, many plastic surgeons and orthopaedic surgeons graduated from foreign countries and came back to Thailand. They played a vital role in the treatment of the surgery of the hand and set up hand units in many centers. They also contributed to the establishment of the “Thai Society for Surgery of the Hand,” which still continues to operate. In the third phase (1975-2000), there was a dramatic development of microsurgery because of the rapid economic expansion. There were many replantation, free tissue transfers, and brachial plexus surgeries in traffic and factory-related accidents. The first hand-fellow training program began in 1993. In the fourth phase (since 2000), the number of hand injuries from factory-related accidents began declining. But the injury from traffic accidents had been increasing both in severity and number. Moreover, the diseases of hand that relate to aging and degeneration had been on the rise. Thai hand surgeons have been using several state-of-the-art technologies such as arthroscopic and endoscopic surgery. They are continuing to invent innovations, generating international publications, and frequently being invited as speakers in foreign countries.


2021 ◽  
pp. 102986492110015
Author(s):  
Lindsey Reymore

This paper offers a series of characterizations of prototypical musical timbres, called Timbre Trait Profiles, for 34 musical instruments common in Western orchestras and wind ensembles. These profiles represent the results of a study in which 243 musician participants imagined the sounds of various instruments and used the 20-dimensional model of musical instrument timbre qualia proposed by Reymore and Huron (2020) to rate their auditory image of each instrument. The rating means are visualized through radar plots, which provide timbral-linguistic thumbprints, and are summarized through snapshot profiles, which catalog the six highest- and three lowest-rated descriptors. The Euclidean distances among instruments offer a quantitative operationalization of semantic distances; these distances are illustrated through hierarchical clustering and multidimensional scaling. Exploratory Factor Analysis is used to analyze the latent structure of the rating data. Finally, results are used to assess Reymore and Huron’s 20-dimensional timbre qualia model, suggesting that the model is highly reliable. It is anticipated that the Timbre Trait Profiles can be applied in future perceptual/cognitive research on timbre and orchestration, in music theoretical analysis for both close readings and corpus studies, and in orchestration pedagogy.


2001 ◽  
Vol 28 (1) ◽  
pp. 98-110 ◽  
Author(s):  
Bruce F Sparling ◽  
Alan G Davenport

Large amplitude cable vibrations are difficult to predict using linear theory due to the presence of sag in the suspended profile. A numerical study was therefore undertaken to investigate the dynamic behaviour of inclined cables excited by imposed displacements. To model the nonlinear nature of cable response, a time domain finite element approach was adopted using nonlinear catenary cable elements. Two types of horizontal displacement patterns were enforced at the upper end of the guy. In the first phase of the study, harmonic displacement histories with a wide range of forcing frequencies were considered. In the second phase, random enforced displacements were used to simulate the motion of a guyed mast in gusty winds. The influence of aerodynamic drag and damping forces was investigated by performing analyses under still air, steady wind, and turbulent wind conditions. It was found that nonlinear coupling of related harmonic response components was significant at certain critical frequencies, particular when the excitation was harmonic and acted in the plane of the guy. Positive aerodynamic damping was shown to effectively suppress resonant and nonlinear coupling response.Key words: cables, structural dynamics, wind loading, finite element method, nonlinear analysis, guyed towers.


2011 ◽  
Vol 403-408 ◽  
pp. 4859-4866 ◽  
Author(s):  
Saptarshi Das ◽  
Amitava Gupta ◽  
Shantanu Das

Generalization of the frequency domain robust tuning has been proposed in this paper for a family of fractional order (FO) PI/PID controllers. The controller tuning is enhanced with two new FO reduced parameter templates which are capable of capturing higher order process dynamics with much better accuracy. The paper validates the proposed methodology with a standard test-bench of higher order processes to show the relative merits of the family of FO controller structures.


2021 ◽  
Vol 66 (1) ◽  
pp. 23-38
Author(s):  
Joyanta Sarkar ◽  
Anil Rai

"Meghalaya is a richly inhabited Indian state. Drums, flutes of bamboo and hand-held small cymbals are a common ensemble. The advent of Christianity in the middle of the 20th century marked the start of a decline in tribal popular music. Over time, Meghalaya’s music scene has evolved, attracting many talented artists and bands from both traditional and not-so traditional genres. Any of the most recent Meghalaya musicians and bands is: The Plague Throat, Kerios Wahlang, Cryptographik Street Poets, etc., Soulmate, Lou Majaw, and Snow White. Meghalaya’s music is characterised by traditional instruments and folk songs. The Musical Instruments of Meghalaya are made from local materials. Meghalayan people honour powerful natural forces and aim to pacify animistic spirits and local gods. The instruments are made of bamboo, flesh, wood, and animal horn. Any one of these musical instruments is considered to have the ability to offer material benefits. The Meghalaya musical instrument is an essential part of traditional folk music in the region. In this article, we offer an overview of the folk musical instruments of Meghalaya. Keywords: Idiophone, Aerophone, Chordophone, Membranophone, Trumpet. "


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