Genetic Algorithm vs Expert System - artificial-intelligence

I'm having some doubts about which system should I use for a new software.
No code has been written yet, I'm just breaking apart all the needs and only then start coding.
This will be implemented in a computer company that provides services for other companies, onsite and remotely.
These are my variables:
Number of technicians
Location of customer
Type of problem
Services already scheduled for the technician
Expertise of the technician about the situation
Customer priority
Maybe some are missing, but these are the most important ones.
This job is being done manually, and has humans, we fail to see the best route to be taken sometimes.
Let's say that a customer calls with a printer problem.
First, check which tech knows about printers.
Then, is the tech available? far from the customer? can it be done remotely (software issues)?
Can it be done by another tech who is closer from the customer location?
Does this customer have more priority than the other where the same tech should be going?
Is the technician schedule full? If yes, pass to another printer/hardware tech.
I know my english is not perfect (not my natural language), but I'll try to provide more details or correct the text as needed.
So, my question is this, what kind of approach would you take? Genetic algorithm seems nice for this kind of job, and I also have some experience with GAF and WatchMaker (Java GA Framework). However, when reading the text above, an expert system seems also appropriate.
Have someone done something like this?!I had search for this kind of software and couldn't find anything alike.
Would another approach be better than the two asked?!
Also, I'm building up a table with all the techs capabilities and expertise, with simple rules like, 1 to 5 about each expertise. This is also a decision factor.
Thanks.

Why not do both? Use an expert system (a rule engine) to define your constraints and use a metaheuristic (such as Local Search or Genetic Algorithms) to solve it. The planning engine OptaPlanner (java, open source) does exactly that (by using the rule engine Drools). The architecture look likes this:
Here's a video demonstrating the constraint flexibility on the vehicle routing problem (VRP). Your problem seems to be an advanced variant on VRP (which is a variant on TSP).

Maybe you can start off with TSP,
here http://en.m.wikipedia.org/wiki/Travelling_salesman_problem
I guess it only deals with the distance.

Related

looking for a good project to work on as my graduation project in the university that involves Ai / Machine Learning, please help me

I need help to chose a project to work on for my master graduation, The project must involve Ai / Machine learning or Business intelegence.. but if there is any other suggestion out of these topics it is Ok, please help me.
One of the most rapid growing areas in AI today is Computer Vision. There are many practical needs where the results of your Master Thesis can be helpful. You can try research something like Emotion Detection, Eye-Tracking, etc.
An appropriate work for a MS in CS in any good University can highlight the current status of research on this field, compare different approaches and algorithms. As a practical part, it makes also a lot of fun when your program recognizes your mood properly :)
Netflix
If you want to work more on non trivial datasets (not google size, but not trivial either and with real application), with an objective measure of success, why not working on the netflix challenge (the first one) ? You can get all the data for free, you have many papers on it, as well as pretty good way to compare your results vs other peoples (since everyone used exactly the same dataset, and it was not so easy to "cheat", contrary to what happens quite often in the academic literature). While not trivial in size, you can work on it with only one computer (assuming it is recent enough), and depending on the type of algorithms you are using, you can implement them in a language which is not C/C++, at least for prototyping (for example, I could get decent results doing things entirely in python).
Bonus point, it passes the "family" test: easy to tell your parents what you are working on, which is always a pain in my experience :)
Music-related tasks
A bit more original: something that is both cool, not trivial but not too complicated in data handling is anything around music, like music genre recognition (classical / electronic / jazz / etc...). You would need to know about signal processing as well, though - I would not advise it if you cannot get easy access to professors who know about the topic.
I can use the same answer I used on a previous, similar question:
Russ Greiner has a great list of project topics for his machine learning course, so that's a great place to start.
Both GAs and ANNs are learners/classifiers. So I ask you the question, what is an interesting "thing" to learn? Maybe it's:
Detecting cancer
Predicting the outcome between two sports teams
Filtering spam
Detecting faces
Reading text (OCR)
Playing a game
The sky is the limit, really!
Since it has a business tie in - given some input set determine probable business fraud from the input (something the SEC seems challenged in doing). We now have several examples (Madoff and others). Or a system to estimate investment risk (there are lots of such systems apparently but were any accurate in the case of Lehman for example).
A starting point might be the Chen book Genetic Algorithms and Genetic Programming in Computational Finance.
Here's an AAAI writeup of an award to the National Association of Securities Dealers for a system thatmonitors NASDAQ insider trading.
Many great answers posted already, but I wanted to add my 2 cents.There is one hot topic in which big companies all around are investing lots of resources into, and is still a very challenging topic with lots of potential: Automated detection of fake news.
This is even more relevant nowadays where most of us are connecting though social media and there's a huge crisis looming over.
Fake news, content removal, source reliability... The problem is huge and very exciting. It is as I said challenging as it can be seen from many perspectives (from analising images to detect fakes using adversarial netwotks to detecting fake written news based on text content (NLP) or using graph theory to find sources) and the possbilities for a research proyect are endless.
I suggest you read some general articles (e.g this or this) or have a look at research articles from the last couple of years (a quick google seach will throw you a lot of related stuff).
I wish I had the opportunity of starting over a project based on this topic. I think it's going to be of the upmost relevance in the next few years.

Star rating system

I'm building an application as part of a course project which allows users to rate an place/event .
My basic question is how should I proceed in this ?
In what language should I write my code ?
If a user provides a 5-star rating, how do I collect it and put it in the database ?
Any guidelines on how to put the initial steps would be very helpful as my knowledge relating to web services is very weak.
Any help/pointers to more information would be very appreciated
Your question is overly vague and isn't related to system administration, so it's probably going to get closed once someone comes along with the appropriate privileges. However, as long as it's here...
My basic question is how should I proceed in this ?
If you are completely at a loss you may want to spend some time consulting with your instructor, who may be able to suggest likely sources of information and provide some direction for your work.
In what language should I write my code ?
You should write your code in a language with which you are familiar that allows you to fulfill the requirements of the project. Anything else will needlessly extend the amount of time it takes to complete the project. If your goal is to learn a new language, you face a mind-numbing number of choices. Python, Ruby, and PHP are all see wide use in web applications. On Microsoft platforms, .NET is quite popular. You will find proponents and detractors for all of them.
If a user provides a 5-star rating, how do I collect it and put it in the database ?
This looks suspiciously like you're asking us to do your assignment for you.

system for absences

I would like to know what should be a good option to implement a system like that:
The system will be use by teachers in a school. They can login and see a list of the pupils that they have in the current class/subject. In this list they could mark the pupils that are not attending the class, and some other options...
The system should also give the option to parents to justify the absences of their childs.
The secretary can access to print some reports related.
This is more or less the system I would like to create.
As you see, doesn't look so complex, but I would like to have an idea about the tools I should use.
As I said before, this is not HOMEWORK, so I hope the next answers take this in consideration.
I'm developing this real system, but I'm confuse about what to use. I was thinking in mysql and php. So I would like to know, even if looks so easy for you, the steps to follow or the different alternatives that I should consider.
UPDATE:
I'm talking with my tutor, and we will go to the company that provides services with the servers, so I can ask them what we need. So normally I thinks the best is to ask for a phpmyadmin (cos we already have sql server). Should I ask sth else that I will need or will make it easier?
Greets
I would use a web front end, with a database containing tables for Classes (which contains the teacher), a table for students, a table hanging off that with details of classes the student takes, and a table for absence details.
You can then set it up so that when a teacher accesses the system they can see the classes they teach, then they select a class it will show the students who take that class. Clicking on a student's name will take you to page where you can enter the absence.
It's a fairly simple set up, but I've developed something similar and it works very well.
By and large there are no tools for developing a certain kind of application. Tools are graded by complexity of application, choice of OS / platform and what programming languages you know.
So if you are a Windows kind of guy you might choose to use SQL Server Express, VB.Net and maybe Visio. Whereas if you're a FOSS fan then perhaps MySQL, PHP and Dia would suit you better. (Of course many FOSS products - including the three I mention - are available in versions which run in Windows, so it is not necessarily clear cut).
This is part of your internship? If so, you ought to use something which is compatible with what your employers use.
edit
Okay, so your internship is with a school, and they don't do much in the way of IT. In that case, if your skillz are mad enough I would suggest you go for the LAMP stack, as it is cheaper.
I would be careful about looking to roll this out to parents. That will elevate your application to a whole new world of concerns: unauthorised access to citizens' private data is a big deal right now, so this will land you with a lot of complexities you do not want to have to handle. Build an app for the teachers only. Get that working. Then if you have time on your hands look at deploying it to a wider audience.
A simple GUI and MySQL Backend should suffice.
Create a List of pupils, put 4 buttons next to each pupil (there, missing, excused, late) and just store it in a database for each class.
Report generation isn't that hard either, just execute the necessary selects (something like: select pupil_id, count(*) from class where state='missing') whenever someone clicks the reports->[...] menu items.
Of course it greatly depends on which other specs exist, but since this sounds like homework i think this should suffice.
OK, so you'll need access from multiple clients, so web based would be ok. You'll need persistent data that is rather primitive. So you might use almost any persistence solution. A RDBMS would be the most common choice, but CouchDB or other BigTable'ish implementations would also suffice.
Other than that you're free in your choice. Java, PHP, Ruby, C++ use whatever you like. Mysql, postgres, couchdb, xml flatfile are all valid choices for persistence.
Without more informations it's not possible to pinpoint a set of technologies ;-)

Trialware/licensing strategies [closed]

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I wrote a utility for photographers that I plan to sell online pretty cheap ($10). I'd like to allow the user to try the software out for a week or so before asking for a license. Since this is a personal project and the software is not very expensive, I don't think that purchasing the services of professional licensing providers would be worth it and I'm rolling my own.
Currently, the application checks for a registry key that contains an encrypted string that either specifies when the trial expires or that they have a valid license. If the key is not present, a trial period key is created.
So all you would need to do to get another week for free is delete the registry key. I don't think many users would do that, especially when the app is only $10, but I'm curious if there's a better way to do this that is not onerous to the legitimate user. I write web apps normally and haven't dealt with this stuff before.
The app is in .NET 2.0, if that matters.
EDIT: You can make your current licensing scheme considerable more difficult to crack by storing the registry information in the Local Security Authority (LSA). Most users will not be able to remove your key information from there. A search for LSA on MSDN should give you the information you need.
Opinions on licensing schemes vary with each individual, more among developers than specific user groups (such as photographers). You should take a deep breath and try to see what your target user would accept, given the business need your application will solve.
This is my personal opinion on the subject. There will be vocal individuals that disagree.
The answer to this depends greatly on how you expect your application to be used. If you expect the application to be used several times every day, you will benefit the most from a very long trial period (several month), to create a lock-in situation. For this to work you will have to have a grace period where the software alerts the user that payment will be needed soon. Before the grace period you will have greater success if the software is silent about the trial period.
Wether or not you choose to believe in this quite bold statement is of course entirely up to you. But if you do, you should realize that the less often your application will be used, the shorter the trial period should be. It is also very important that payment is very quick and easy for the user (as little data entry and as few clicks as possible).
If you are very uncertain about the usage of the application, you should choose a very short trial period. You will, in my experience, achieve better results if the application is silent about the fact that it is in trial period in this case.
Though effective for licensing purposes, "Call home" features is regarded as a privacy threat by many people. Personally I disagree with the notion that this is any way bad for a customer that is willing to pay for the software he/she is using. Therefore I suggest implementing a licensing scheme where the application checks the license status (trial, paid) on a regular basis, and helps the user pay for the software when it's time. This might be overkill for a small utility application, though.
For very small, or even simple, utility applications, I argue that upfront payment without trial period is the most effective.
Regarding the security of the solution, you have to make it proportional to the development effort. In my line of work, security is very critical because there are partners and dealers involved, and because the investment made in development is very high. For a small utility application, it makes more sense to price it right and rely on the honest users that will pay for the software that address their business needs.
There's not much point to doing complicated protection schemes. Basically one of two things will happen:
Your app is not popular enough, and nobody cracks it.
Your app becomes popular, someone cracks it and releases it, then anybody with zero knowledge can simply download that crack if they want to cheat you.
In the case of #1, it's not worth putting a lot of effort into the scheme, because you might make one or two extra people buy your app. In the case of #2, it's not worth putting a lot of effort because someone will crack it anyway, and the effort will be wasted.
Basically my suggestion is just do something simple, like you already are, and that's just as effective. People who don't want to cheat / steal from you will pay up, people who want to cheat you will do it regardless.
If you are hosting your homepage on a server that you control, you could have the downloadable trial-version of your software automatically compile to a new binary every night. This compile will replace a hardcoded datetime-value in your program for when the software expires. That way the only way to "cheat" is to change the date on your computer, and most people wont do that because of the problems that will create.
Try the Shareware Starter Kit. It was developed my Microsoft and may have some other features you want.
http://msdn.microsoft.com/en-us/vs2005/aa718342.aspx
If you are planning to continue developing your software, you might consider the ransom model:
http://en.wikipedia.org/wiki/Street_Performer_Protocol
Essentially, you develop improvements to the software, and then ask for a certain amount of donations before you release them (without any DRM).
One way to do it that's easy for the user but not for you is to hard-code the expiry date and make new versions of the installer every now and then... :)
If I were you though, I wouldn't make it any more advanced than what you're already doing. Like you say it's only $10, and if someone really wants to crack your system they will do it no matter how complicated you make it.
You could do a slightly more advanced version of your scheme by requiring a net connection and letting a server generate the trial key. If you do something along the lines of sign(hash(unique_computer_id+when_to_expire)) and let the app check with a public key that your server has signed the expiry date it should require a "real" hack to bypass.
This way you can store the unique id's serverside and refuse to generate a expiry date more than once or twice. Not sure what to use as the unique id, but there should be some way to get something useful from Windows.
I am facing the very same problem with an application I'm selling for a very low price as well.
Besides obfuscating the app, I came up with a system that uses two keys in the registry, one of which is used to determine that time of installation, the other one the actual license key. The keys are named obscurely and a missing key indicates tampering with the installation.
Of course deleting both keys and reinstalling the application will start the evaluation time again.
I figured it doesn't matter anyway, as someone who wants to crack the app will succeed in doing so, or find a crack by someone who succeeded in doing so.
So in the end I'm only achieving the goal of making it not TOO easy to crack the application, and this is what, I guess, will stop 80-90% of the customers from doing so. And afterall: as the application is sold for a very low price, there's no justification for me to invest any more time into this issue than I already have.
just be cool about the license. explain up front that this is your passion and a child of your labor. give people a chance to do the right thing. if someone wants to pirate it, it will happen eventually. i still remember my despair seeing my books on bittorrent, but its something you have to just deal with. Don't cave to casual piracy (what you're doing now sounds great) but don't cripple the thing beyond that.
I still believe that there are enough honest people out there to make a for-profit coding endeavor worth while.
Don't have the evaluation based on "days since install", instead do number of days used, or number of times run or something similar. People tend to download shareware, run it once or twice, and then forget it for a few weeks until they need it again. By then, the trial may have expired and so they've only had a few tries to get hooked on using your app, even though they've had it installed for a while. Number of activation/days instead lets them get into a habit of using your app for a task, and also makes a stronger sell (i.e. you've used this app 30 times...).
Even better, limiting the features works better than timing out. For example, perhaps your photography app could limit the user to 1 megapixel images, but let them use it for as long as they want.
Also, consider pricing your app at $20 (or $19.95). Unless there's already a micropayment setup in place (like iPhone store or XBoxLive or something) people tend to have an aversion to buying things online below a certain price point (which is around $20 depending on the type of app), and people assume subconciously if something is inexpensive, it must not be very good. You can actually raise your conversion rate with a higher price (up to a point of course).
In these sort of circumstances, I don't really think it matters what you do. If you have some kind of protection it will stop 90% of your users. The other 10% - if they don't want to pay for your software they'll pretty much find a way around protection no matter what you do.
If you want something a little less obvious you can put a file in System32 that sounds like a system file that the application checks the existence of on launch. That can be a little harder to track down.

Software evaluation licensing [closed]

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My company is looking to start distributing some software we developed and would like to be able to let people try the software out before buying. We'd also like to make sure it can't be copied and distributed to our customers' customers.
One model we've seen is tying a license to a MAC address so the software will only work on one machine.
What I'm wondering is, what's a good way to generate a license key with different information embedded in it such as license expiration date, MAC address, and different software restrictions?
I've used both FLEXlm from Macrovision (formerly Globetrotter) and the newer RLM from Reprise Software (as I understand, written by FlexLM's original authors). Both can key off either the MAC address or a physical dongle, can be either node-locked (tied to one machine only) or "floating" (any authorized machine on the network can get a license doled out by a central license server, up to a maximum number of simultaneously checked-out copies determined by how much they've paid for). There are a variety of flexible ways to set it up, including expiration dates, individual sub-licensed features, etc. Integration into an application is not very difficult. These are just the two I've used, I'm sure there are others that do the job just as well.
These programs are easily cracked, meaning that there are known exploits that let people either bypass the security of your application that uses them, either by cutting their own licenses to spoof the license server, or by merely patching your binary to bypass the license check (essentially replacing the subroutine call to their library with code that just says "return 'true'". It's more complicated than that, but that's what it mostly boils down to. You'll see cracked versions of your product posted to various Warez sites. It can be very frustrating and demoralizing, all the more so because they're often interested in cracking for cracking sake, and don't even have any use for your product or knowledge of what to do with it. (This is obvious if you have a sufficiently specialized program.)
Because of this, some people will say you should write your own, maybe even change the encryption scheme frequently. But I disagree. It's true that rolling your own means that known exploits against FLEXlm or RLM won't instantly work for your application. However, unless you are a total expert on this kind of security (which clearly you aren't or you wouldn't be asking the question), it's highly likely that in your inexperience you will end up writing a much less secure and more crackable scheme than the market leaders (weak as they may be).
The other reason not to roll your own is simply that it's an endless cat and mouse game. It's better for your customers and your sales to put minimal effort into license security and spend that time debugging or adding features. You need to come to grips with the licensing scheme as merely "keeping honest people honest", but not preventing determined cracking. Accept that the crackers wouldn't have paid for the software anyway.
Not everybody can take this kind of zen attitude. Some people can't sleep at night knowing that somebody somewhere is getting something for nothing. But try to learn to deal with it. You can't stop the pirates, but you can balance your time/effort/expense trying to stop all piracy versus making your product better for users. Remember, sometimes the most pirated applications are also the most popular and profitable. Good luck and sleep well.
I'd suggest you take the pieces of information you want in the key, and hash it with md5, and then just take the first X characters (where X is a key length you think is manageable).
Cryptographically, it's far from perfect, but this is the sort of area where you want to put in the minimum amount of effort which will stop a casual attacker - anything more quickly becomes a black hole.
Oh, I should also point out, you will want to provide the expiration date (and any other information you might want to read out yourself) in plain text (or slightly obfuscated) as part of the key as well if you go down this path - The md5 is just to stop the end user from changing he expiration date to extend the license.
The easiest thing would be a key file like this...
# License key for XYZZY
expiry-date=2009-01-01
other-info=blah
key=[md5 has of MAC address, expiry date, other-info]
We've used the following algorithm at my company for years without a single incident.
Decide the fields you want in the code. Bit-pack as much as possible. For example, dates could be "number of days since 2007," and then you can get away with 16-bits.
Add an extra "checksum" field. (You'll see why in a second.) The value of this field is a checksum of the packed bytes from the other fields. We use "first 32 bits from MD5."
Encrypt everything using TEA. For the key, use something that identifies the customer (e.g. company name + personal email address), that way if someone wants to post a key on the interweb they have to include their own contact info in plain text.
Convert hex to a string in some sensible way. You can do straight hex digits but some people like to pick a different set of 16 characters to make it less obvious. Also include dashes or something regularly so it's easier to read it over the phone.
To decrypt, convert hex to string and decrypt with TEA. But then there's this extra step: Compute your own checksum of the fields (ignoring the checksum field) and compare to the given checksum. This is the step that ensures no one tampered with the key.
The reason is that TEA mixes the bits completely, so if even one bit is changed, all other bits are equally likely to change during TEA decryption, therefore the checksum will not pass.
Is this hackable? Of course! Almost everything is, but this is tight enough and simple to implement.
If tying to contact information is not sufficient, then include a field for "Node ID" and lock it to MAC address or somesuch as you suggest.
Don't use MAC addresses. On some hardware we've tested - in particular some IBM Thinkpads - the MAC address can change on a restart. We didn't bother investigating why this was, but we learned quite early during our research not to rely on it.
Obligatory disclaimer & plug: the company I co-founded produces the OffByZero Cobalt licensing solution. So it probably won't surprise you to hear that I recommend outsourcing your licensing, & focusing on your core competencies.
Seriously, this stuff is quite tricky to get right, & the consequences of getting it wrong could be quite bad. If you're low-volume high-price a few pirated copies could seriously dent your revenue, & if you're high-volume low-price then there's incentive for warez d00dz to crack your software for fun & reputation.
One thing to bear in mind is that there is no such thing as truly crack-proof licensing; once someone has your byte-code on their hardware, you have given away the ability to completely control what they do with it.
What a good licensing system does is raise the bar sufficiently high that purchasing your software is a better option - especially with the rise in malware-infected pirated software. We recommend you take a number of measures towards securing your application:
get a good third-party licensing system
pepper your code with scope-contained checks (e.g. no one global variable like fIsLicensed, don't check the status of a feature near the code that implements the feature)
employ serious obfuscation in the case of .NET or Java code
The company I worked for actually used a usb dongle. This was handy because:
Our software was also installed on that USB Stick
The program would only run if it found the (unique) hardware key (any standard USB key has that, so you don't have to buy something special, any stick will do)
it was not restricted to a computer, but could be installed on another system if desired
I know most people don't like dongles, but in this case it was quite handy as it was actually used for a special purpose media player that we also delivered, the USB keys could thus be used as a demo on any pc, but also, and without any modifications, be used in the real application (ie the real players), once the client was satisfied
We keep it simple: store every license data to an XML (easy to read and manage), create a hash of the whole XML and then crypt it with a utility (also own and simple).
This is also far from perfect, but it can hold for some time.
Almost every commercial license system has been cracked, we have used many over the years all eventually get cracked, the general rule is write your own, change it every release, once your happy try to crack it yourself.
Nothing is really secure, ultimately look at the big players Microsoft etc, they go with the model honest people will pay and other will copy, don't put too much effort into it.
If you application is worth paying money for people will.
I've used a number of different products that do the license generation and have created my own solution but it comes down to what will give you the most flexibility now and down the road.
Topics that you should focus on for generating your own license keys are...
HEX formating, elliptic curve cryptography, and any of the algorithms for encryption such as AES/Rijndael, DES, Blowfish, etc. These are great for creating license keys.
Of course it isn't enough to have a key you also need to associate it to a product and program the application to lock down based on a key system you've created.
I have messed around with creating my own solution but in the end when it came down to making money with the software I had to cave and get a commercial solution that would save me time in generating keys and managing my product line...
My favorite so far has been License Vault from SpearmanTech but I've also tried FlexNet (costly), XHEO (way too much programming required), and SeriousBit Ellipter.
I chose the License Vault product in the end because I would get it for much cheaper than the others and it simply had more to offer me as we do most of our work in .NET 3.5.
It is difficult to provide a good answer without knowing anything about your product and customers. For enterprise software sold to technical people you can use a fairly complex licensing system and they'll figure it out. For consumer software sold to the barely computer-literate, you need a much simpler system.
In general, I've adopted the practice of making a very simple system that keeps the honest people honest. Anyone who really wants to steal your software will find a way around any DRM system.
In the past I've used Armadillo (now Software Passport) for C++ projects. I'm currently using XHEO for C# projects.
If your product requires the use of the internet, then you can generate a unique id for the machine and use that to check with a license web service.
If it does not, I think going with a commercial product is the way to go. Yes, they can be hacked, but for the person who is absolutely determined to hack it, it is unlikely they ever would have paid.
We have used: http://www.aspack.com/asprotect.aspx
We also use a function call in their sdk product that gives us a unique id for a machine.
Good company although clearly not native English speakers since their first product was called "AsPack".

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