# fiveworlds

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1. ## Hotel Room Occupancy Optimization Problem

It is plenty interesting for me I am making a website for a real travel agency which takes bookings for many hotels and flights. All bookings require approval from the hotel and I don't want to force guests to move too much.
2. ## Disable a bullet gun with magnetic fields?

There was a gun for cops that used an electromagnetic field to stop the firing mechanism with finger recognition. So if the cop was disarmed by an attacker the gun would be useless. You could also stop the firing mechanism remotely. The design was flawed though because a strong magnet could get it to fire again. A better idea would be to use a small motor to stop the firing mechanism that way a magnet would be of no help to an attacker.
3. ## Disable a bullet gun with magnetic fields?

Yes put the gun with bullets in an oven. I doubt it. You could do it to a missile though.
4. ## Hotel Room Occupancy Optimization Problem

Yeah we have them here too. It would be cool to get that to work for hotels but it would also be a lot more difficult. Cinemas tend to follow a very tabular seating arrangement therefore you can just use a table to map all the seats. A hotel is different because the general layout is generally not as tabular you would be looking at using image maps which involve actual people working coordinates out for the map so it wouldn't scale as easily.
5. ## Hotel Room Occupancy Optimization Problem

So this is the database entity relationship diagram that I have at the moment. A user can log into the wordpress site fill in a few details the size of the room etc. and a booking reference is generated for that customer pending approval. Customers that have already been approved a place have to be given a room but I can assign any room to customers that have yet to be approved. It is difficult because while I don't want customers waiting too long for approval I also want to fill as many rooms as possible limiting the amount customers have to change rooms. It is easy to just fill the hotel until all spots are occupied since I know the number of rooms available in total.
6. ## Hotel Room Occupancy Optimization Problem

Given a list of customers, dates, and requested room types. How to find the most optimal hotel room allocation where hotel patrons would have to move rooms the least and maximize the total number of customers.
7. ## free energy?

Definitely, I seriously doubt he managed to get a bulb as large as that to light that way.
8. ## free energy?

Magnet causes electrons in the copper plate to move in a certain direction. This causes electromagnetic induction in the two coils which in turn causes electromagnetic induction in the bulb.
9. ## Table management excel help

Would it not be better to use a server for that so people can simply load the website and mark whether they are working from home? You could use an excel macro for it. https://www.excel-easy.com/vba.html
10. ## Basic Universal Income (BUI)

That everyone gets it obviously. But that doesn't stop the government putting conditions on it like you either have to be working or in school or something. There would be nothing to stop the government not paying you because you protested something etc. Take the welfare system here you have to be actively looking for work in order to get it. If you go protest something then the government can stop your payment because on that particular day you were not actively looking for work.
11. ## Basic Universal Income (BUI)

Pro Everybody gets a small amount of money so they can survive even if they don't have a job. Everybody should at a minimum have access to education. Guaranteed income for non-working parents and caregivers. (such as those with disabled children or parents with Alzheimer's) Con Rent prices could increase due to people having more disposable income therefore there is no guarantee homelessness will be eliminated. (eg. rent allowance here is 300 a month max. There was no houses here to rent in 2018 for anything less than 320) Less Incentive to work. Genuine poor may receive less targeted support since everyone gets money. Gives the government unprecedented control over people. (eg. If you want to keep you BUI you must attend course a or b and achieve minimum grade y) Cost of living in different areas could be higher which people in politics often forget. (eg. A family lives in the countryside they have to travel to pick up the BUI, get groceries etc which is more expensive than somebody living in the city who doesn't have to travel)
12. ## Mixing Washing Powder

I generally buy whatever washing powder is cheapest in the supermarket which means I wind up with a load of different brands. Is it safe to mix the end of one box of washing powder with washing powder from a different brand?
13. ## Computer Science

Where? http://www.claymath.org/millennium-problems/rules-millennium-prizes There is a rule however that states I need to publish in a peer reviewed journal which I cannot because most of them only accept papers from people with degrees that I don't have. So therefore I couldn't enter the competition if I wanted to. Yes it does. The difference between a DTM and an NDTM is to do with the movement of the read head. If the read head can read the whole problem without moving then the problem is in P. If the problem requires an infinite tape then the read head has to move. Therefore all you need to do to prove p = np is prove that no reasonable problem requires an infinite tape. The internal working of how a Turing Machine calculates anything then becomes irrelevant you can use any algorithm even existing ways of calculating travelling salesman etc. https://en.wikipedia.org/wiki/Non-deterministic_Turing_machine
14. ## Computer Science

Actually I will prove you cannot use ZFC to solve p vs np. A turing machine reads a two number tape {a,b} and gets the power. a^b does not equal b^a therefore {1,3} and {3,1} are not equal sets and ZFC cannot be used to solve p vs np.
15. ## Computer Science

That's nonsense there is no proof that ZFC is versatile enough to write p vs np in either direction. P vs np details a set of problems which you have to prove work on a deterministic Turing machine in a polynomial amount of time. For instance I can prove that I can replace words in sentences with a deterministic Turing machine in polynomial time using the following python function which replicates the action of a real deterministic Turing machine. But it can do more than that you can easily replace cities "Cork, London, New York, Brussels" with their shortest travelling salesman result. There is of course a limitation of the number of cities but it'll work for flights and stuff. Did you know that time complexity on a Turing machine is measured by how many moves the read/write head has to make. Therefore if you make the read/write head large enough to read any input on your tape you never need to move the read head anything but forward making all algorithms O(n). Of course there is a problem with that approach because a Turing machine allows for an infinite tape size and it is not possible to have an infinitely large read head. So you could prove p=np simply by showing that no problem requires an infinite amount of tape.
16. ## Publicly disclosing a new product on the internet...

"first to file" is definitely a thing even if there is a post on a website that is not proof enough that you were the original inventor if somebody else files a patent application. Unfortunately this is very true not many people can afford an international patent. Applying for a patent in the US only protects that patent in the US an international patent can cost thousands more and still won't be respected in some countries. There is a website that files international patents but it is very expensive. http://www.wipo.int/pct/en/
17. ## Publicly disclosing a new product on the internet...

No all patents must be filed with the relevant authority. For yourself that is https://www.uspto.gov/patents-application-process/applying-online/about-efs-web You must then pay the subsequent fees. https://www.uspto.gov/learning-and-resources/fees-and-payment/uspto-fee-schedule It is possible to fill out the application yourself if you feel confident or don't have the money to pay a lawyer. Note that not all countries will respect your patent. So it is not always the best route to patent things as people in countries such as china can still copy your patent and sell your product without your consent. Sometimes you are better keeping the design a trade secret (like the coca cola recipe) if possible.
18. ## Please Anyone Know of any links for a gifted 12 year old to help challenge him.

Yeah it is everything is practice this kid is book smart and probably thinks the other kids are stupid so he won't learn to play and he won't learn to care about others. His mom is good at these things and can teach him.
19. ## Please Anyone Know of any links for a gifted 12 year old to help challenge him.

Kids like that tend be bad with emotional intelligence and sports. If you want to challenge the kid maybe you should teach him sports and get him teach him to care about other people.
20. ## Comp Sci in the RAF or as a civilian?

Yes I have heard that too. They pay for your accommodation, food, training etc. Working in computer science as a civilian has advantages too. Most of the larger companies Apple, Microsoft etc own (or part own) eLearning platforms (linkedin, udemy etc) which allows you and your family to learn anything for free. They will also contribute to your internet bills if you choose to work from home and you will be allowed to travel all of the time. My brother spends all his time travelling the world and working remotely. They will also pay for your food in you work on campus and provide uniforms. The RAF won't allow you to travel unless it is to war etc so if you want to travel being a civilian is the way to go. The RAF will ensure you keep yourself fit though and might be more interesting since you have access to military tech and might teach you to fly. You should look into GCHQ/Navy too I would imagine they have some cool tech to keep you interested. In terms of money the only real benefit of the RAF is the accommodation which you probably won't use if you ever get married.
21. ## Networks

Web 2.0 is just useless jargon it isn't a specification of anything and it doesn't add anything new. You could always use cgi to make an interactive website like facebook.
22. ## Magnet-Based artificial gravity

Well yeah because the repulsion is really weak. You'd need a magnet even stronger again and I want to figure out how strong it would actually need to be.
23. ## Networking settings for an idiot...

No they aren't. Most people in the US and Europe have a dynamic ip address basically when you connect to the ISP's router you get an ip address automatically and when they reset their router you get a new ip. Companies have a static ip address this means that the ISP's always gives the same ip address to the company every time they connect to the internet. Dns is how a domain name is converted to an ip address Dynamic Dns is a paid service in which companies update the ipadress that the domain name is pointing to. They do this through the use of software. Dynamic Dns can be free but is unreliable. The benefit of the static ip is that if you have a camera watching your garden and the ISP resets their router you still have internet access. With a dynamic ip you could be offline for half an hour or more each time.
24. ## Magnet-Based artificial gravity

Magnets weakly repel organic tissue. How strong an electromagnet would be required to simulate artificial gravity and would a magnetic field that strong be harmful to a person?
25. ## Networking settings for an idiot...

For dynamic dns if you don't want to get a static ip you could use https://www.noip.com/ (free) and an android app to update your ip to their server https://play.google.com/store/apps/details?id=jf.actualizaip
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