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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:
The Fourmilab Units Calculator is based upon the GNU Units utility. It supports expressions in the “Convert” and “To” fields in the same syntax as described in the GNU Units manual. If the To field is left blank, the definition of the unit in the Convert field will be shown in terms of fundamental units. Entering “?” in the To field shows all standard units with the same dimensions as the expression in the Convert field. A total of 3460 linear units, 109 nonlinear units, and 109 prefixes are defined.
The shipping container ecosystem is governed by requirements that determine almost everything about them. In a previous article, we covered all the common (and some not-so-common) shipping container dimensions. But below, we’ll focus on how containers are described, classified, and constructed.
Convert between Bytes, KB, MB, GB, TB and KiB, MiB, GiB, TiB
ASCII Table
the salt spray chamber pumps a 5% salt fog solution into its atmosphere for the duration of the test, which rapidly accelerates corrosion. //
- The salt spray environment is much more aggressive and concentrated than even a marine setting (the salt concentration of the ocean is roughly 3%).
- Salt spray tests for many common platings and coatings can last multiple days – with some tests lasting 500 hours or more before the parts begin to rust – while stainless steel parts can begin to exhibit signs of rust in as little as a few hours of exposure. Per ASTM A967 and A380, stainless parts are shown to be properly passivated if they resist corrosion in salt spray for just 2 hours.
- Stainless steel performs relatively poorly in salt spray because the constant exposure to a harsh environment rapidly erodes the passivation layer and prevents it from reforming. With the passivation layer inhibited, the base material is exposed and the part quickly begins to corrode.
The copper sulfate test is a visual method of determining the existence of free iron in specifically stainless steel. In many cases, the copper sulfate test is used as a pass/fail examination of a passivation process on a part or stock material, but it can also be used as a test to determine if passivation is necessary in the first place. //
http://everyspec.com/MIL-STD/MIL-STD-0700-0799/MIL_STD_753C_1117/
The method is specifically designed to work with stainless steel alloys with a minimum of 16% chromium as stated in the document.
The procedure is as follows:
- Prepare test solution – Dissolve 8 grams of copper sulfate in 500 ml of distilled water in which 2 – 3 ml of sulfuric acid has been added.
This will take approximately 5 minutes and should be mixed completely before using. It is noted in the documentation that solutions older than 2 weeks shall not be used for the test. The dilution by weight of the test is 1.6% which is on the lower end of the copper sulfate solution dilution.
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Swab the surface to be inspected with test solution – keep surface wet for a period of 6 minutes.
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Carefully rinse and dry the surface such that no copper deposits are removed.
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Copper deposits indicate the presence of metallic iron.
- Multiply the volume in cubic feet by 62.44 to obtain total pounds of water
- 2 ppm is 0.000002 for maintenance
- 4 ppm is 0.000004 for shock reduction
Therefore, to calculate the amount of Copper Sulfate Pentahydrate to treat 1 acre-foot of water (43,560 cu ft) with 2 ppm Copper Sulfate, the calculation would be:
43,560 * 62.44 = 2,719,886.4 * 0.000002 = 5.44 lbs. Copper Sulfate
Waterscapes & Fountains:
Dissolve 1/4lb CuSO4 in one gallon of water for every 7500 gallons
Swimming Pools:
2lbs (4ppm) per 60,000 gals (8,000 cu ft) to reduce algae, 1lb (2ppm) for maintenance
The running slope is to be uniform along a run, although slight variations may occur with certain materials such as concrete. No other changes in level other than the running slope (1:12 maximum) and cross slope (1:48 maximum) are permitted. //
Ramp runs must have a clear width of 36″ minimum (measured between handrails where provided). //
The height of runs is limited (30″ maximum), but there is no limit on the number of runs a ramp may have. //
Intermediate landings between runs must be at least 60″ wide clear and 60″ long clear where ramps change direction (any change from linear). Handrails, edge protection, vertical posts and other elements cannot obstruct or overlap the minimum 60″ by 60″ clearance. //
Handrails are required on both sides of ramps with a rise greater than 6″.
Handrail height of 34-38" consistent along length, 20-28" in play areas. //
Edge protection along ramp runs and landings keep wheelchair casters and crutch tips on the surface and can be provided by curbs, barriers, or extended surfaces.
- Curbs if used must be at least 4″ high.
- Rails or other barriers must prevent passage of a 4″ diameter sphere.
- Vertical pickets used for edge protection must prevent passage of a 4″ diameter sphere.
- Run and landing surfaces that extend at least 12″ beyond the inside face of handrails will provide adequate edge protection by preventing wheelchair casters and crutch tips from slipping off the edge.
What is a “color space?”
Well first you take some colors.
- red
- yellow
- blue
And then you arrange them, however you like, into some kind of space: //
What might a useful color space do? Well, just like the RYB color wheel, maybe it could help us predict how different colors will mix.
And lo, in 1931, an international team of experts got together in England and laid out a color space that does exactly that1. They used science and math. They called themselves the International Commission on Illumination (aka le Commission Internationale de l'Éclairage, aka the CIE), and they called their color space CIE XYZ.
CI-4
Severe-Duty Diesel Engine Service
The CI-4 performance requirements describe oils for use in those high speed, four-stroke cycle diesel engines designed to meet 2004 exhaust emission standards, to be implemented October 2002. These oils are compounded for use in all applications with diesel fuels ranging in sulfur content up to 0.05% by weight
The API SN category is an improvement over the API SM category in the following areas:
- High temperature deposit protection for pistons
- Better sludge control
- Better seal compatibility
- Aftertreatment compatibility
The Flammable Range (also called Explosive Range) is the concentration range of a gas or vapor that will burn (or explode) if an ignition source is introduced.
Three basic requirements must be met for explosion to take place:
- flammable substance - fuel
- oxidizer - oxygen or air
- source of ignition - spark or high heat
Below the explosive or flammable range the mixture is too lean to burn and above the upper explosive or flammable limit the mixture is too rich to burn. The limits are commonly called the "Lower Explosive or Flammable Limit" (LEL/LFL) and the "Upper Explosive or Flammable Limit" (UEL/UFL).
Filter Media Reference Guide
Filtration Medium Basic Characteristics Discussion