On a chilly October evening in 1958, a group of MIT students shuffled onto the Harvard Bridge, which separates the university town of Cambridge from Boston proper. The shortest among them lay down on the sidewalk at the bridge's start, his friends marked his length, he got up, moved forward, and repeated the process.
The man in question was Oliver Smoot, then a freshman at the institution who was pledging to join the Lambda Chi Alpha fraternity. As part of his initiation, he was tasked with measuring the Harvard Bridge using his own height. The resulting unit, the "smoot," remains visible on the bridge today, with its markings repainted annually.
Local police even use these markings to pinpoint locations of traffic incidents. Google Earth also includes it as a unit, measuring five feet seven inches (170.18 cm) - you can find it as the last item under "Settings," then "Distance units."
Smoot went on to a career in standards and policy within the technology sector. After holding various roles, he served as chairman of the American National Standards Institute (ANSI) from 2001 to 2002 and later as president of the International Organization for Standardization (ISO) from 2003 to 2005.
RTDs, utilized for their high accuracy and stability, are inherently more sensitive to vibration than thermocouples—especially traditional wire-wound designs.
Newly announced catalog collects pre-2022 sources untouched by ChatGPT and AI contamination. //
As it turns out, his pre-AI website isn't new, but it has languished unannounced until now. "I created it back in March 2023 as a clearinghouse for online resources that hadn't been contaminated with AI-generated content," he wrote on his blog.
The website points to several major archives of pre-AI content, including a Wikipedia dump from August 2022 (before ChatGPT's November 2022 release), Project Gutenberg's collection of public domain books, the Library of Congress photo archive, and GitHub's Arctic Code Vault—a snapshot of open source code buried in a former coal mine near the North Pole in February 2020. The wordfreq project appears on the list as well, flash-frozen from a time before AI contamination made its methodology untenable.
The site accepts submissions of other pre-AI content sources through its Tumblr page. Graham-Cumming emphasizes that the project aims to document human creativity from before the AI era, not to make a statement against AI itself. As atmospheric nuclear testing ended and background radiation returned to natural levels, low-background steel eventually became unnecessary for most uses. Whether pre-AI content will follow a similar trajectory remains a question.
Still, it feels reasonable to protect sources of human creativity now, including archival ones, because these repositories may become useful in ways that few appreciate at the moment. For example, in 2020, I proposed creating a so-called "cryptographic ark"—a timestamped archive of pre-AI media that future historians could verify as authentic, collected before my then-arbitrary cutoff date of January 1, 2022. AI slop pollutes more than the current discourse—it could cloud the historical record as well.
For now, lowbackgroundsteel.ai stands as a modest catalog of human expression from what may someday be seen as the last pre-AI era. It's a digital archaeology project marking the boundary between human-generated and hybrid human-AI cultures. In an age where distinguishing between human and machine output grows increasingly difficult, these archives may prove valuable for understanding how human communication evolved before AI entered the chat.
When using thermocouple sensors, the thermocouple wire used to carry the signal is just as important as the thermocouple sensor itself. Thermocouple wire is made from the same allow materials as the thermocouple sensor, and its primary role is to extend the thermocouple circuit from sensing junction (“hot junction”) to the measurement instrument (“cold junction”) without introducing additional errors.
Using thermocouple-grade wire or extension-grade wire helps ensure maximum temperature measurement accuracy - minimizing errors related to alloy composition or calibration mismatch.
Over the course of a job, you may notice a customer has an unsafe electrical installation or equipment.
An Electrical Danger Notification* certificate is designed to be used by NICEIC registered electricians to provide a formal record that the customer has been informed of such danger. Apart from helping identifying unsafe appliances, the certificate will specify any work done to make it safe, and any urgent work that needs to be done after the date.
Terminal Velocity Calculator
In typical applications, magnetic flow meters are sized so that the velocity at maximum flow is approximately 2-3 meters per second. Differential pressure constraints and/or process conditions may preclude application of this general guideline. //
For slurry service, be sure to size magnetic flow meters to operate above the velocity at which solids settle (typically 1 ft/sec), in order to avoid filling the pipe with solids that can affect the measurement and potentially stop flow. Magnetic flow meters for abrasive service are usually sized to operate at low velocity (typically below 3 ft/sec) to reduce wear. In abrasive slurry service, the flow meter should be operated above the velocity at which solids will settle, despite increased wear.
One MCM is equivalent to 1000 circular mils. For comparison, 1 MCM equates to 0.5067 square mm, so for many purposes , a ratio of 2MCM to 1mmsq can be used with a 1.3% (very small) error.
Immediately Dangerous to Life or Health Concentrations (IDLH)
CAS number: 124–38–9
NIOSH REL: 5,000 ppm (9,000 mg/m3) TWA,
30,000 ppm (54,000 mg/m3) STEL
Current OSHA PEL: 5,000 ppm (9,000 mg/m3) TWA
1989 OSHA PEL: 10,000 ppm (18,000 mg/m3) TWA,
30,000 ppm (54,000 mg/m3) STEL
Basis for original (SCP) IDLH: The chosen IDLH is based on the statements by ACGIH [1971] that a 30-minute exposure at 50,000 ppm produces signs of intoxication, and a few minutes of exposure at 70,000 ppm and 100,000 ppm produces unconsciousness [Flury and Zernik 1931]. AIHA [1971] reported that 100,000 ppm is the atmospheric concentration immediately dangerous to life. In addition, Hunter [1975] noted that exposure to 100,000 ppm for only a few minutes can cause loss of consciousness.
OSHA PEL
8-hour TWA
(ST) STEL
(C) Ceiling
Peak
NIOSH REL
Up to 10-hour TWA
(ST) STEL
(C) Ceiling
ACGIH TLV©
8-hour TWA
(ST) STEL
(C) Ceiling
CAL/OSHA PEL
8-hour TWA
(ST) STEL
(C) Ceiling
Peak
PEL-TWA
5000 ppm (9000 mg/m³)
This calculator determines the absolute pressure at the pump impeller. NPSHA must exceed the NPSHR (net positive suction head requirement specified by the pump manufacturer or caviation and/or loss of prime will occur.
Nylon is one of the oldest and most commonly used thermoplastics but there still seems to be a lot of confusion about properly drying nylon and in general about how nylon is affected by moisture. //
You could use a nylon 12 which does not absorb as much moisture but Nylon 12 is really expensive.
The first form calculates the pressure or friction loss along a given length of pipeline with a specified inside diameter. The second form calculates the minimum pipe size to limit pressure loss to a specified value.
Additional friction pressure losses occur due to fittings. These losses in-effect add extra additional length to the total pipeline. Use this calculator to estimate how much additional length needs to be added to the overall pipe length below in order to estimate these additional losses. Learn more about the units used on this page.
All types of resistors have their own resistor symbols which are used when a circuit diagram is drawn. This page will explain the different standards which are used for resistor symbols and display the most common symbols.
A thread of 20 Survival Tips And Tricks You Might Not Have Known Before.
Sold in sets of 8 container corner castings (or individually)
Meets the ISO Standard (ISO 1161) for Container Corner Castings with Regard to Dimensions
There are 2 each of 4 different marine shipping container corner castings per set:
Bottom Left, Bottom Right and Top Left and Top Right
How many feet of water in 1 psi? The answer is 2.3066587368787. We assume you are converting between foot of water [4 °C] and pound/square inch.
- 1 foot of water to psi = 0.43353 psi
- 5 foot of water to psi = 2.16764 psi
- 10 foot of water to psi = 4.33528 psi
- 20 foot of water to psi = 8.67055 psi
- 30 foot of water to psi = 13.00583 psi
- 40 foot of water to psi = 17.3411 psi
- 50 foot of water to psi = 21.67638 psi
- 75 foot of water to psi = 32.51456 psi
- 100 foot of water to psi = 43.35275 psi
Have you ever had a teacher who was very smart but terrible at teaching? An expert who used so much jargon you could not follow their explanation? This is called the “curse of knowledge”, a term coined in 1989 by economists Colin Camerer, George Loewenstein, and Martin Weber.
It’s a cognitive bias that occurs when someone incorrectly assumes that others have enough background to understand. For example, your smart professor might no longer remember the challenges a young student faces when learning a new subject. And the expert might overlook the need to simplify concepts, assuming everyone knows what they know. //
You can avoid the negative effects of the curse of knowledge by constantly questioning your assumptions as to how much exactly your audience knows.
Curse of Knowledge - Mitigating Strategies
- Get to know your audience. Try to know how much they know. If you’re talking to a friend or colleague, assess the extent of their knowledge before starting your explanation. If you’re talking to potential customers, ask a few questions before starting your sales pitch.
- Simplify your language. Don’t hide behind jargon and complex terminology. Use simple language and clear examples to make your point easier to understand even with limited knowledge.
- Use storytelling. Stories can make information more relatable and memorable. Relate complex concepts to familiar experiences. Analogies and metaphors can also make abstract ideas more concrete and understandable.
- Show, don’t tell. A picture can be worth a thousand words. Instead of a lengthy explanation, see if you can create a visual, a graph, or an illustration that conveys the same content in a more accessible way.
- Engage in active teaching. Encourage questions and discussions. Pause at every step to ensure the person is following. By engaging your audience, you can better gauge their level of understanding and adjust your explanations accordingly.
What’s great about simplifying your explanations is that it reinforces your own knowledge. If you can’t explain something without using complicated jargon, you’re probably not as familiar with it as you think. Making the effort to explain concepts in simpler terms ensures you truly understand them.
Welcome to Fourmilab's calendar converter! This page allows you to interconvert dates in a variety of calendars, both civil and computer-related.
- Gregorian Calendar
- Julian Day
- Julian Calendar
- Hebrew Calendar
- Islamic Calendar
- Persian Calendar
- Mayan Calendars
A new flashlight for 2008: The Surefire Backup!
I bought this in spring 2008 and it is wonderful. Almost as much light as the L4, 2/3 the size, single 123 cell with an hour at full brightness, almost a day at the dimmer setting, and the beam is narrower so it really throws well. This one light may be all I need!
My 2003 favorite flashlight: