A-weighting is a frequency weighting used in sound measurements to reflect the relative loudness perceived by the human ear. The human auditory system does not respond equally across all frequencies; it is more sensitive to mid-frequency sounds (typically around 1 kHz to 4 kHz) and less sensitive to very low and very high frequencies.
Acoustic radiation force is a phenomenon that occurs when an acoustic wave, such as ultrasound, interacts with an object or a medium. It results from the pressure variations produced by the sound waves as they propagate and can lead to a net force acting on small particles, bubbles, or biological tissues within the medium. ### Key Aspects of Acoustic Radiation Force: 1. **Mechanism**: When an ultrasound wave passes through a medium, it generates regions of high and low pressure.
Bought December 2023 for 300 pounds, so 15 pounds / TB. Needs power supply unfrotunately besides USB, the largest one without needing power supply was only 5 TB at the time so not worth it, given that my P14s alreay carriers 2 TB. 10x is a must for the external crap.
www.westerndigital.com/en-gb/products/external-drives/wd-elements-desktop-usb-3-0-hdd?sku=WDBWLG0030HBK-EESN (archive)
Noise: it has a constant pleasant hum, with a not so nice click every 5 seconds or so. Reasonable, but not amazingly incredible.
The size is reasonable, not megaportable, but definitely reasonable.
The natural sciences are not just a tool to predict the future.
They are a reminder that the lives that we live daily are mere illusions, religious concepts such as Maya and Samsara come to mind.
We as individuals perceive nothing about the materials that we touch every day really work, nor more importantly how our brain and cell work.
Everything is magic out of our control.
The natural sciences allow us peek, with huge concentrated effort, into tiny little bits a little of those unknowns, and blow our minds as we notice that we don't know anything.
For all practical purposes in life, there is a huge macro micro gap. We are only able to directly perceive and influence the macro events. And through those we try to affect micro events. Because for good or bad, micro events reflect in the macro world.
It is as if we live in a different plane of existence above molecules, and below galaxies. The hierarchy of Figure "xkcd 435: Fields arranged by purity" puts that nicely into perspective, shame it only starts at the economical level, not going up to astronomy.
The great beauty of science is that it allows us to puncture through some of the layers of reality, either up or down, away from our daily experience.
And the great beauty of artificial intelligence research is that it allows to peer deeper into exactly our layer of existence.
Every one or two weeks Ciro Santilli remembers that he and everything he touches are just a bunch of atoms, and that is an amazing feeling. This is Ciro's preferred source of Great doubt. Another concept that comes to mind is when you see it, you'll shit bricks.
Perhaps, the feeling of physics and the illusion of life reaches its peak in molecular biology.
Just look at your fucking hand right now.
Do you have any idea of each of the cells in it work? Isn't is at least 100 times more complex than the materials of the table you hand is currently resting on?
This is the non-science fiction version of the lotus-Eater Machine.
Alan Watts's "Philosopher" talk mentions related ideas:
The origin of a person who is defined as a philosopher, is one who finds that existence itself is exceedingly odd.
The toddler of a friend of Ciro Santilli's wife asked her mum:Our perception of the macroscopic world is so magic that children have to learn the difference between living and non-living things.
James Somers put it very well as well in his article I should have loved biology by James Somers, this quote was brought to Ciro's attention by Bert Hubert's website[ref].The same applies to other natural sciences.
I should have loved biology but I found it to be a lifeless recitation of names: the Golgi apparatus and the Krebs cycle; mitosis, meiosis; DNA, RNA, mRNA, tRNA.In the textbooks, astonishing facts were presented without astonishment. Someone probably told me that every cell in my body has the same DNA. But no one shook me by the shoulders, saying how crazy that was. I needed Lewis Thomas, who wrote in The Medusa and the Snail:For the real amazement, if you wish to be amazed, is this process. You start out as a single cell derived from the coupling of a sperm and an egg; this divides in two, then four, then eight, and so on, and at a certain stage there emerges a single cell which has as all its progeny the human brain. The mere existence of such a cell should be one of the great astonishments of the earth. People ought to be walking around all day, all through their waking hours calling to each other in endless wonderment, talking of nothing except that cell.
Alan Watts' "Philosopher" talk (1973)
Source. Lecture given at UCLA on 1973-02-21. Some key quotes from the talk:The origin of a person who is defined as a philosopher, is one who finds that existence itself is exceedingly odd.
Conditioned play audiometry (CPA) is a behavioral testing method used to assess hearing in young children, typically aged 2 to 5 years, who may not be able to respond to traditional audiometric testing methods like pure-tone audiometry. In CPA, the child is conditioned to respond to sounds by engaging in a play activity that requires them to indicate they have heard a sound.
The term "hypersonic effect" typically refers to the phenomena associated with objects traveling at hypersonic speeds, which are defined as speeds greater than Mach 5 (five times the speed of sound in air). When an object moves at hypersonic speeds, it experiences a range of physical effects due to the extreme velocities involved, including: 1. **Shock Waves**: At hypersonic speeds, the flow of air around the object generates powerful shock waves.
The Institute of Acoustics (IOA) is a professional body in the United Kingdom dedicated to the advancement of the study and practice of acoustics. Founded in 1974, the IOA promotes the interests of those involved in acoustics, noise, and vibration control, providing a platform for professionals across various sectors, including engineering, environmental science, architecture, and audio technology.
Noise pollution refers to the excessive or harmful levels of noise in the environment, which can have detrimental effects on human health, wildlife, and overall quality of life. It is typically caused by various human activities and can include sounds from traffic, industrial operations, construction work, loud music, and other sources. Key aspects of noise pollution include: 1. **Sources**: Common sources of noise pollution include road traffic, airplanes, trains, factories, construction sites, and heavy machinery.
The Safe-In-Sound Award is a recognition given for excellence in hearing conservation practices within the workplace. It is presented by the National Hearing Conservation Association (NHCA) and recognizes organizations and programs that demonstrate outstanding commitment to protecting workers' hearing and preventing noise-induced hearing loss. The award highlights best practices in hearing conservation and serves as a model for other organizations. Recipients typically showcase effective strategies, innovative programs, and proactive measures that promote safe listening environments.
Timbre, often referred to as the "color" or "quality" of sound, is the characteristic that allows us to differentiate between different sources of sound, even if they are producing the same pitch and loudness. It encompasses the unique differences in sound quality that distinguish one instrument or voice from another. Several factors contribute to timbre, including: 1. **Harmonics**: The presence and amplitude of overtones (harmonics) produced along with the fundamental frequency.
A transverse wave is a type of wave where the oscillation or displacement of the medium is perpendicular to the direction in which the wave travels. In other words, if the wave is moving horizontally, the particles of the medium are moving up and down.
Voicing in the context of pipe organs refers to the process of adjusting and fine-tuning the individual pipes to achieve the desired tonal quality and character of each stop. This involves manipulating various aspects of the pipe to ensure that it produces the intended sound. The goal of voicing is to ensure that the pipes blend well with each other and contribute to a harmonious overall sound when played together.
An acoustic membrane is a type of material designed to control sound transmission and improve acoustic performance in various environments. These membranes are often used in building construction, audio equipment, and noise control applications. Their primary functions include sound attenuation, sound diffusion, and vibration damping. ### Key Characteristics of Acoustic Membranes: 1. **Material Composition**: Acoustic membranes can be made from a variety of materials, including polymers, composites, and specialized acoustic fabrics.
Echoencephalography, also known as ultrasound encephalography, is a medical imaging technique that uses ultrasound waves to visualize the brain. This non-invasive method is primarily employed to assess brain structures and detect abnormalities, particularly in infants and children, where traditional imaging techniques like CT scans or MRIs may not be as feasible or safe. The procedure involves placing a transducer on the patient's skull, which emits ultrasound waves that penetrate the skull and reflect off the brain tissues.
Power bandwidth, often referred to in the context of signal processing and communications, is defined as the range of frequencies over which a system can effectively transmit or process signals without significant attenuation or distortion. It is typically defined as the difference between the upper and lower cutoff frequencies where the output power drops to a certain specified level (often -3 dB or half-power point) relative to its peak value.
In acoustics, the term "prefix" can refer to a specific type of sound signal or analysis used in the context of audio processing, measurement, and signal analysis. While "prefix" itself is not a standard term widely recognized in acoustics, it might relate to specific applications such as prefixes used in measurement units or descriptions of sound waves, such as in prefixing certain terms (like "sub", "ultra", or "micro") that indicate particular characteristics of sound frequencies or levels.
Target strength (TS) is a measure used in acoustics and sonar to quantify how well an object reflects sound waves, particularly in underwater environments. It is an important concept in fields such as underwater acoustics, marine biology, sonar technology, and fisheries research. Target strength is typically expressed in decibels (dB) and is defined as the ratio of the intensity of the reflected sound wave from the target to the intensity of the incident sound wave that strikes the target.
Pinned article: Introduction to the OurBigBook Project
Welcome to the OurBigBook Project! Our goal is to create the perfect publishing platform for STEM subjects, and get university-level students to write the best free STEM tutorials ever.
Everyone is welcome to create an account and play with the site: ourbigbook.com/go/register. We belive that students themselves can write amazing tutorials, but teachers are welcome too. You can write about anything you want, it doesn't have to be STEM or even educational. Silly test content is very welcome and you won't be penalized in any way. Just keep it legal!
Intro to OurBigBook
. Source. We have two killer features:
- topics: topics group articles by different users with the same title, e.g. here is the topic for the "Fundamental Theorem of Calculus" ourbigbook.com/go/topic/fundamental-theorem-of-calculusArticles of different users are sorted by upvote within each article page. This feature is a bit like:
- a Wikipedia where each user can have their own version of each article
- a Q&A website like Stack Overflow, where multiple people can give their views on a given topic, and the best ones are sorted by upvote. Except you don't need to wait for someone to ask first, and any topic goes, no matter how narrow or broad
This feature makes it possible for readers to find better explanations of any topic created by other writers. And it allows writers to create an explanation in a place that readers might actually find it.
Figure 1. Screenshot of the "Derivative" topic page. View it live at: ourbigbook.com/go/topic/derivativeVideo 2. OurBigBook Web topics demo. Source. - local editing: you can store all your personal knowledge base content locally in a plaintext markup format that can be edited locally and published either:This way you can be sure that even if OurBigBook.com were to go down one day (which we have no plans to do as it is quite cheap to host!), your content will still be perfectly readable as a static site.
- to OurBigBook.com to get awesome multi-user features like topics and likes
- as HTML files to a static website, which you can host yourself for free on many external providers like GitHub Pages, and remain in full control
Figure 3. Visual Studio Code extension installation.
Figure 4. Visual Studio Code extension tree navigation.
Figure 5. Web editor. You can also edit articles on the Web editor without installing anything locally.Video 3. Edit locally and publish demo. Source. This shows editing OurBigBook Markup and publishing it using the Visual Studio Code extension.Video 4. OurBigBook Visual Studio Code extension editing and navigation demo. Source. 
- Infinitely deep tables of contents:
All our software is open source and hosted at: github.com/ourbigbook/ourbigbook
Further documentation can be found at: docs.ourbigbook.com
Feel free to reach our to us for any help or suggestions: docs.ourbigbook.com/#contact