This is a small presentation on Architectural Acoustics and Reverberation Time that i made for my coursework. it is not that detailed and explanatory (made for only 2 marks), but i thought sharing this might help someone with their study. So forgive me if u get disappointed, and feel free to reach me if u have any questions/complain or suggestion.
Notes for Architecture 4th Year subject Services. The topic is about Acoustic, how does it work for different places, how we can treat spaces according to acoustic and for better acoustic
An acoustic case study that covers a research of the project of "The Solaris and Leisure Centre, Estonia ", documenting through writings, sketches, acoustical information and photos. This would help to understand the various aspects of designing and constructing an auditorium keeping the acoustics in mind.
WHAT IS ACOUSTICS? what is sound? AMPLITUDE AND VOLUME, FREQUENCY AND PITCH
LOUDNESS OR INTENSITY
LOUDNESS OR INTENSITY
LOUDNESS OR INTENSITY, TIMBRE
VELOCITY OF SOUND
AMPLITUDE
REFLECTION
Notes for Architecture 4th Year subject Services. The topic is about Acoustic, how does it work for different places, how we can treat spaces according to acoustic and for better acoustic
An acoustic case study that covers a research of the project of "The Solaris and Leisure Centre, Estonia ", documenting through writings, sketches, acoustical information and photos. This would help to understand the various aspects of designing and constructing an auditorium keeping the acoustics in mind.
WHAT IS ACOUSTICS? what is sound? AMPLITUDE AND VOLUME, FREQUENCY AND PITCH
LOUDNESS OR INTENSITY
LOUDNESS OR INTENSITY
LOUDNESS OR INTENSITY, TIMBRE
VELOCITY OF SOUND
AMPLITUDE
REFLECTION
Explains basics about sound and what classroom issues are present due to sound effects which causes problem for students to hear teacher properly.
Explains concept of reverberation and other issues and suggests about its solution for better classroom sound efficiency
“a science that deals with the production, control, transmission, reception, and effects of sound.”
it is the science of controlling sound within buildings.
Visit https://alexisbaskind.net/teaching for a full interactive version of this course with sound and video material, as well as more courses and material.
Course series: Fundamentals of acoustics for sound engineers and music producers
Level: undergraduate (Bachelor)
Language: English
Revision: February 2020
To cite this course: Alexis Baskind, Room Acoustics
course material, license: Creative Commons BY-NC-SA.
Course content:
1. Time-Space perspective: Sound propagation in a room
Raytracing, example of a rectangular room, evolution from free field to diffuse field, initial time delay gap (ITDG), direct sound, first reflections, late reverberation, exponential decay of the pressure, definition of the reverberation time, T60, T30, T20, Schroeder curve, critical distance, flutter echoes, diffusion, effect of distance, effect of room size
2. Frequency-Space perspective: Room modes
Reminder: monodimensional standing waves, axial modes, tangential modes, oblique modes, eigenfrequencies, effect of room size on modal density, duration and bandwidth of modes, effect of absorption on modes, Schroeder Frequency
3. Time-Frequency perspective
Early reflections, modes and diffuse reverberation in an unified time-frequency perspective, waterfall view
4. Room acoustics design
prediction of the reverberation time, Sabine formula, frequency-dependent absorption, porous absorbers, effect of absorber’s thickness and air gap, resonant absorbers, membrane absorbers, Helmholtz absorbers
5. Room acoustics of listening rooms
importance of symmetry, need for a sufficient room size and controlled reverberation time, recommended reverberation time, need for controlling the early reflections, LEDE design, RFZ design
6. Spatial hearing in a room
perception of distance in a room, perception of the room size, clarity, apparent source width, envelopment, reverberation timbre
Explains basics about sound and what classroom issues are present due to sound effects which causes problem for students to hear teacher properly.
Explains concept of reverberation and other issues and suggests about its solution for better classroom sound efficiency
“a science that deals with the production, control, transmission, reception, and effects of sound.”
it is the science of controlling sound within buildings.
Visit https://alexisbaskind.net/teaching for a full interactive version of this course with sound and video material, as well as more courses and material.
Course series: Fundamentals of acoustics for sound engineers and music producers
Level: undergraduate (Bachelor)
Language: English
Revision: February 2020
To cite this course: Alexis Baskind, Room Acoustics
course material, license: Creative Commons BY-NC-SA.
Course content:
1. Time-Space perspective: Sound propagation in a room
Raytracing, example of a rectangular room, evolution from free field to diffuse field, initial time delay gap (ITDG), direct sound, first reflections, late reverberation, exponential decay of the pressure, definition of the reverberation time, T60, T30, T20, Schroeder curve, critical distance, flutter echoes, diffusion, effect of distance, effect of room size
2. Frequency-Space perspective: Room modes
Reminder: monodimensional standing waves, axial modes, tangential modes, oblique modes, eigenfrequencies, effect of room size on modal density, duration and bandwidth of modes, effect of absorption on modes, Schroeder Frequency
3. Time-Frequency perspective
Early reflections, modes and diffuse reverberation in an unified time-frequency perspective, waterfall view
4. Room acoustics design
prediction of the reverberation time, Sabine formula, frequency-dependent absorption, porous absorbers, effect of absorber’s thickness and air gap, resonant absorbers, membrane absorbers, Helmholtz absorbers
5. Room acoustics of listening rooms
importance of symmetry, need for a sufficient room size and controlled reverberation time, recommended reverberation time, need for controlling the early reflections, LEDE design, RFZ design
6. Spatial hearing in a room
perception of distance in a room, perception of the room size, clarity, apparent source width, envelopment, reverberation timbre
ARCHITECTURAL SERVICES – V (ACOUSTICS) (RAR – 806)
MODULE-1 – BUILDING ACOUSTICS
(COMMON ACOUSTICAL DEFECTS AND
RECOMMENDED REMEDIES) Presented by Ar. Manish Kumar, Assistant Professor in
Architecture Department at Axis Institute of
Architecture
Absorption of sound, various materials, Sabine’ s formula, optimum reverberation time, conditions for good acoustics
Sound insulation: Acceptable noise levels, noise prevention at its source, transmission of noise, Noise control-general
considerations
Factors affecting acoustics of buildings and their remedies.Burhanuddin Kapadia
Acoustics plays an important role in the sound ergonomics
due to which sound can be distributed equally to entire hall.
the following slide gives an overview of the factors of acoustics and its remedies.
The distortion of sound we hear is due to "coloration" of the sound caused by reverberation - an invisible physical phenomenon. This presentation brings out the basics of reverberation.
Immunizing Image Classifiers Against Localized Adversary Attacksgerogepatton
This paper addresses the vulnerability of deep learning models, particularly convolutional neural networks
(CNN)s, to adversarial attacks and presents a proactive training technique designed to counter them. We
introduce a novel volumization algorithm, which transforms 2D images into 3D volumetric representations.
When combined with 3D convolution and deep curriculum learning optimization (CLO), itsignificantly improves
the immunity of models against localized universal attacks by up to 40%. We evaluate our proposed approach
using contemporary CNN architectures and the modified Canadian Institute for Advanced Research (CIFAR-10
and CIFAR-100) and ImageNet Large Scale Visual Recognition Challenge (ILSVRC12) datasets, showcasing
accuracy improvements over previous techniques. The results indicate that the combination of the volumetric
input and curriculum learning holds significant promise for mitigating adversarial attacks without necessitating
adversary training.
Final project report on grocery store management system..pdfKamal Acharya
In today’s fast-changing business environment, it’s extremely important to be able to respond to client needs in the most effective and timely manner. If your customers wish to see your business online and have instant access to your products or services.
Online Grocery Store is an e-commerce website, which retails various grocery products. This project allows viewing various products available enables registered users to purchase desired products instantly using Paytm, UPI payment processor (Instant Pay) and also can place order by using Cash on Delivery (Pay Later) option. This project provides an easy access to Administrators and Managers to view orders placed using Pay Later and Instant Pay options.
In order to develop an e-commerce website, a number of Technologies must be studied and understood. These include multi-tiered architecture, server and client-side scripting techniques, implementation technologies, programming language (such as PHP, HTML, CSS, JavaScript) and MySQL relational databases. This is a project with the objective to develop a basic website where a consumer is provided with a shopping cart website and also to know about the technologies used to develop such a website.
This document will discuss each of the underlying technologies to create and implement an e- commerce website.
Water scarcity is the lack of fresh water resources to meet the standard water demand. There are two type of water scarcity. One is physical. The other is economic water scarcity.
Industrial Training at Shahjalal Fertilizer Company Limited (SFCL)MdTanvirMahtab2
This presentation is about the working procedure of Shahjalal Fertilizer Company Limited (SFCL). A Govt. owned Company of Bangladesh Chemical Industries Corporation under Ministry of Industries.
Welcome to WIPAC Monthly the magazine brought to you by the LinkedIn Group Water Industry Process Automation & Control.
In this month's edition, along with this month's industry news to celebrate the 13 years since the group was created we have articles including
A case study of the used of Advanced Process Control at the Wastewater Treatment works at Lleida in Spain
A look back on an article on smart wastewater networks in order to see how the industry has measured up in the interim around the adoption of Digital Transformation in the Water Industry.
Hierarchical Digital Twin of a Naval Power SystemKerry Sado
A hierarchical digital twin of a Naval DC power system has been developed and experimentally verified. Similar to other state-of-the-art digital twins, this technology creates a digital replica of the physical system executed in real-time or faster, which can modify hardware controls. However, its advantage stems from distributing computational efforts by utilizing a hierarchical structure composed of lower-level digital twin blocks and a higher-level system digital twin. Each digital twin block is associated with a physical subsystem of the hardware and communicates with a singular system digital twin, which creates a system-level response. By extracting information from each level of the hierarchy, power system controls of the hardware were reconfigured autonomously. This hierarchical digital twin development offers several advantages over other digital twins, particularly in the field of naval power systems. The hierarchical structure allows for greater computational efficiency and scalability while the ability to autonomously reconfigure hardware controls offers increased flexibility and responsiveness. The hierarchical decomposition and models utilized were well aligned with the physical twin, as indicated by the maximum deviations between the developed digital twin hierarchy and the hardware.
CFD Simulation of By-pass Flow in a HRSG module by R&R Consult.pptxR&R Consult
CFD analysis is incredibly effective at solving mysteries and improving the performance of complex systems!
Here's a great example: At a large natural gas-fired power plant, where they use waste heat to generate steam and energy, they were puzzled that their boiler wasn't producing as much steam as expected.
R&R and Tetra Engineering Group Inc. were asked to solve the issue with reduced steam production.
An inspection had shown that a significant amount of hot flue gas was bypassing the boiler tubes, where the heat was supposed to be transferred.
R&R Consult conducted a CFD analysis, which revealed that 6.3% of the flue gas was bypassing the boiler tubes without transferring heat. The analysis also showed that the flue gas was instead being directed along the sides of the boiler and between the modules that were supposed to capture the heat. This was the cause of the reduced performance.
Based on our results, Tetra Engineering installed covering plates to reduce the bypass flow. This improved the boiler's performance and increased electricity production.
It is always satisfying when we can help solve complex challenges like this. Do your systems also need a check-up or optimization? Give us a call!
Work done in cooperation with James Malloy and David Moelling from Tetra Engineering.
More examples of our work https://www.r-r-consult.dk/en/cases-en/
Cosmetic shop management system project report.pdfKamal Acharya
Buying new cosmetic products is difficult. It can even be scary for those who have sensitive skin and are prone to skin trouble. The information needed to alleviate this problem is on the back of each product, but it's thought to interpret those ingredient lists unless you have a background in chemistry.
Instead of buying and hoping for the best, we can use data science to help us predict which products may be good fits for us. It includes various function programs to do the above mentioned tasks.
Data file handling has been effectively used in the program.
The automated cosmetic shop management system should deal with the automation of general workflow and administration process of the shop. The main processes of the system focus on customer's request where the system is able to search the most appropriate products and deliver it to the customers. It should help the employees to quickly identify the list of cosmetic product that have reached the minimum quantity and also keep a track of expired date for each cosmetic product. It should help the employees to find the rack number in which the product is placed.It is also Faster and more efficient way.
2. Contents
• Acoustic and Architectural Acoustic
• Reverberation and Reverberation Time
• Absorption co-efficient
• Live room and Dead room
• Sabines Formula
• Eyring’s Formula
• Eyring’s Formula To Sabine’s Formula
3. 3
Acoustics
• Acoustics is actually a branch of physics that focuses on studying
sound, how it’s produced, transmitted, controlled, and received, and the
effects of this process.
• There are a few sub-discipline of Acoustics
• Architectural acoustics
• Bioacoustics
• Electroacoustics
• Musical acoustics and more.
In next few slide I will discuss about Architectural Acoustics.
4. 4
Architectural Acoustics
• Architectural acoustics (also known as building
acoustics) is the science and engineering of
achieving a good sound within a building and is a
branch of Acoustical Engineering.
• The first application of modern scientific methods
to architectural acoustics was carried out by the
American physicist Wallace Sabine in the Fogg
Museum lecture room. He applied his newfound
knowledge to the design of Symphony Hall,
Boston. Wallace Clement Sabine
5. 5
Architectural Acoustics
• Architectural acoustics, fundamentally, is the relationship between
a sound produced in a space and its listeners. But it can be so much
more than that!
• Positive architectural acoustics can benefit people’s health,
wellbeing and overall quality of life whereas poor acoustics and
noise disturbance can negatively impact our life.
• For example, The World Health Organisation (WHO) reports that
excessive overnight noise disturbs sleep, raises blood pressure and
can even increase the incidence of heart disease.
6. 6
Reverberation
• Reverberation is when sound waves continue to vibrates after
the original source of the sound has stopped emitting sound.
• Sound produced in a room will repeatedly bounce off
reflective surfaces such as the floor, walls, ceiling, windows or
tables while gradually losing energy. When these reflections
mix with each other, the phenomena known as reverberation is
created. So, that define Reverberation as a collection of
many reflections of sound.
7. 7
Reverberation Time
Reverberation time is a measure of the time required for reflecting
sound to "fade away" in an enclosed area after the source of the
sound has stopped.
Reverberation time T =
0.163 V
Σ S α
sec/m [M.K.S]
Where:
S = Surface area of material
α = Absorption coefficient of the material of the wall
V = Volume of the room
9. 9
Absorption Co-efficient
s
• There is a way to quantify how much
sound is reflected or absorbed in a room
by using a metric called the absorption
coefficient. In a nutshell, an Absorption
Coefficient is a measure of how much
sound is absorbed, and NOT reflected.
• The absorption coefficient ranges
between zero and one, one meaning no
sound energy is reflected and the sound
is either absorbed or transmitted. An
effective absorber will have a sound
absorption coefficient greater than .75
Table 1: The absorption coefficients of the materials
used in the auditorium
10. 10
Live Room And Dead Room
Live room:
A room where the absorption co-efficient is less than 0.4 which is
very small and the reverberation time will be large such a room is known as
live room.
Dead room:
A room where the absorption co-efficient is greater than 0.4 which
is very small and the reverberation time will be lowered such a room is
known as live room.
11. 11
11
Live Room And Dead Room
Live room Dead room
Having absorption ci-efficient less than
0.4
Having absorption ci-efficient greater
than 0.4
Reverberation time is larger Reverberation time is larger
Clarity of sound is adequate Clarity of sound is maximum
Intensity is high Intensity of sound is minimum
Not suitable for public addressing
system.
Best suited for speaking and concerts
Difference between Live room and Dead room:
12. 12
12
Live Room And Dead Room
Which room is good for auditorium?
Because of maximum sound clarity, minimum intensity and having a
larger absorption co-efficient than live room, Dead room is more
suitable for speaking and concerts. That’s why dead room are used
for designing modern auditorium and music hall.
13. 13
SABINES FORMULA
Sabines Formula:
T =
𝟎.𝟏𝟔𝟑 𝐕
𝐀
[M.K.S]
Where,
V = the volume of the enclosed area
A = the total absorption of the enclosed area
Again, if velocity of sound C = 1116ft, then
Reverberation time t =
𝟎.𝟎𝟓 𝐕
𝐀
[F.P.S]
14. 14
Eyring’s Formula
Eyring’s formula
T =
𝟎.𝟏𝟔𝟑 𝐕
−𝑺 log𝒆(𝟏−𝜶)
Where,
S = Total area of the four walls of the room
V = Volume
𝜶 = Absorption co-efficient
15. 15
Eyring’s Formula To Sabine’s Formula
We know that,
Eyring’s formula for the reverberation time of a dead room is
denoted as
T =
𝟎.𝟏𝟔𝟑 𝐕
−𝑺 log𝒆(𝟏−𝜶)
(1)
Now,
log𝒆(𝟏 − 𝜶) = - 𝜶-
𝜶𝟐
𝟐
-
𝜶𝟑
𝟑
- ……
Since 𝜶 is very small, therefore higher derivatives will be
negligible.
16. 16
Eyring’s Formula To Sabine’s Formula
So ,
log𝒆(𝟏 − 𝜶) = - 𝜶
From (1) ,
T =
𝟎.𝟏𝟔𝟑 𝐕
−𝑺 (− 𝜶 )
=
𝟎.𝟏𝟔𝟑 𝐕
𝑺 𝜶
So, Reverberation time,
T =
𝟎.𝟏𝟔𝟑 𝐕
𝐀
where [A = 𝑺 𝜶 ]
