Mathematical analysis | Strongly NP-complete problems | Packing problems
The strip packing problem is a 2-dimensional geometric minimization problem. Given a set of axis-aligned rectangles and a strip of bounded width and infinite height, determine an overlapping-free packing of the rectangles into the strip minimizing its height. This problem is a cutting and packing problem and is classified as an Open Dimension Problem according to Wäscher et al. This problem arises in the area of scheduling, where it models jobs, that require a contiguous portion of the memory over a given time period. Another example is the area of industrial manufacturing, where rectangular pieces need to be cut out of a sheet of material (e.g., cloth or paper) that has a fixed width but infinite length, and one wants to minimize the wasted material. This problem was first studied in 1980. It is strongly-NP hard and there exists no polynomial time approximation algorithm with a ratio smaller than unless . However, the best approximation ratio achieved so far (by a polynomial time algorithm by Harren et al.) is , imposing an open question whether there is an algorithm with approximation ratio . (Wikipedia).
Broken Zipper Bottom Pin – Solved!
In this video we show how to fix a zipper with a broken bottom pin. Symptoms of this include the zipper appearing to function and zipping up but the bottom then separates later. All household DIY videos in a single playlist (https://www.youtube.com/playlist?list=PLxdnSsBqCrrEt05uhC6NenK_
From playlist Household DIY
I guess this is what happens when you don't put anything up to keep the shopping carts from falling out of the truck.
From playlist Inertia
What to do with all those old PCBs from stuff you've taken apart...
From playlist Projects & Installations
Loose the screw for moving the stopper to new position and then tighten it. The stopper is kept immobile by wedge mechnism.
From playlist Mechanisms
Donuts are paralyzed with embarrassment (and as a result unable to escape) when someone is laughing at them.
From playlist Videos with my cats!
Why do shoelaces untie themselves?
Failure to stay knotty is a two-stage process according to a new study of lace mechanics. Learn more: http://scim.ag/2oVypF9
From playlist Materials and technology
Wordpress Problems Solved Pt 1
Here I show you how to solve common Wordpress problem's. How to post content easily, how to upload images, how to upload video, how to upload documents, Press This, and Scripd.
From playlist Wordpress Tutorial
The Perfect Push-Up To Build Muscle (AVOID THESE MISTAKES!)
Due to the high amount of muscle mass and joints which are involved in this exercise, there is a lot that can go wrong when it comes to the pushup form or in a pushups workout. Which is not only detrimental for growth, but is also problematic from an injury and pain standpoint since we ten
From playlist EXERCISE FORM TIPS
Erik Demaine - New Ways to Fold a Cube from Paper - CoM Oct 2021
What shapes of paper can fold into a unit cube? This seemingly simple question has many interesting answers and open problems, depending on what type of folding is allowed. In particular, we’ll see a new way to fold a 3 × 3 square into a unit cube using horizontal, vertical, and diagonal c
From playlist Celebration of Mind 2021
The Wandering Earth 1/6 Spacesuit Lighting Mod!
Norm reviews a stunning 1/6 scale recreation of the spacesuits from The Wandering Earth, and compares this figure to the original Weta Workshop-made costumes we saw at Comic-Con. We also add lights to this spacesuit to replicate what was on the original, using a mix of COB LED strips and n
From playlist Toys, Models and Collectibles
How To Squat Without Knee Pain (4 Mistakes You’re Probably Making)
Today we’ll be covering how to squat properly to avoid knee pain when squatting or knee pain after squats. Squats are a fantastic compound exercise that allows you to develop muscles in your lower body. However, the amount of knee pain people experience following squats has made some wary
From playlist EXERCISE FORM TIPS
The Nematic to High Density Disordered Phase Transition in a System of Long Rigid... by Deepak Dhar
DISCUSSION MEETING STATISTICAL PHYSICS: RECENT ADVANCES AND FUTURE DIRECTIONS (ONLINE) ORGANIZERS: Sakuntala Chatterjee (SNBNCBS, Kolkata), Kavita Jain (JNCASR, Bangalore) and Tridib Sadhu (TIFR, Mumbai) DATE: 14 February 2022 to 15 February 2022 VENUE: Online In the past few dec
From playlist Statistical Physics: Recent advances and Future directions (ONLINE) 2022
A new twist on pasta dough could reshape food manufacturing
Mighty morphing power… pastas? They might not be as action packed as Power Rangers, but a new type of programmable dough could make packing pasta a whole lot easier, according to a new study in Science Advances. Bulky pastas—such as farfalle and fusilli—require more packaging than thinne
From playlist Materials and technology
Storm-Proofing New York's Subway | Strip the City
New York's subway and bus system has more than seven million daily riders. | For more Strip the City, visit http://science.discovery.com/tv-shows/strip-the-city/#mkcpgn=ytsci1 Subscribe to Science Channel! | http://www.youtube.com/subscription_center?add_user=sciencechannel Watch full ep
From playlist Strip the City
How We Got the Science of Weight Loss Wrong - with Giles Yeo
All of the calorie counts you see on food today are wrong. Obesity researcher Giles Yeo shows why calories are not created equal. Giles' newest book "Why Calories Don't Count" is available now: https://geni.us/rjch7M Watch the Q&A: https://youtu.be/S5F0x1HZSBs Giles Yeo explores what you
From playlist Livestreams
Matt Kahle (3/11/21): Configurations spaces of particles: homological solid, liquid, and gas
Title: Configurations spaces of particles: homological solid, liquid, and gas Abstract: Configuration spaces of points in the plane are well studied and the topology of such spaces is well understood. But what if you replace points by particles with some positive thickness, and put them i
From playlist Topological Complexity Seminar
Starting a truck with a Makita drill battery and more - big installation fun!
Fun & games on a recent lighting installation
From playlist Projects & Installations
The Best Science-Based Plan To Get Six Pack Abs (3 Simple Steps)
Let’s face it, six pack abs are something that most men want. In fact, one of the most common questions I get asked is “how to get six pack abs” or “how to get abs fast”. However, most people are unfortunately brainwashed by a lot of the bad advice out there promising 6 pack abs. In this v
From playlist FAT LOSS TIPS
Yes. I make mistakes ... rarely. http://www.flippingphysics.com
From playlist Miscellaneous
Cinematic Mode - This is Only a Test 619 - 9/30/21
The duocast streak continues as Jeremy tags in this week to discuss real world use of iPhone's cinematic video mode, the nitpicking of iPad Mini's jelly roll screen effect, porting Medal of Honor to the Quest 2, and Amazon's slate of home robots. Plus, Norm demos a new type of LED strip he
From playlist This Is Only a Test