0
votes
0answers
3 views

Calculating speed up

I want to calculate speedup for a computer: Suppose you run a job on two clusters, the first composed by 100 task nodes, the second composed by 200 task nodes of equal hardware characteristics. What ...
0
votes
0answers
2 views

How to choose proper activation functions for hidden and output layers of a perceptron neural network?

As far as I know choosing an activation function for the input layer is relatively straightforward: I use Sigmoid if the input data domain is (0,1) and TANH if it is (-1,1). But what activation ...
1
vote
0answers
5 views

Complexity of finding the pseudoinverse matrix

How many arithmetic operations are required to find a Moore–Penrose pseudoinverse matrix of a arbitrary field? If the matrix is invertible and complex valued, then it's just the inverse. ...
1
vote
1answer
9 views

Concrete and simple applications for bipartite graphs

I am looking for concrete and simple problems that may be solved using bipartite graphs or bipartite graph properties. Any idea along with explanations are welcome.
0
votes
0answers
8 views

Simultaneous execution on a Von Neuman architecture

I have a CS course at Uni. Had an exam about two last week with a question I did not get, but still, am not totally comfortable with the expected answer. Basically, we were asked Many processes ...
0
votes
0answers
6 views

Where to go for depth in Computer Science? [on hold]

I am actually an undergraduate student enrolled in a physics programme. I did some programming at school in C and C++ and html. Also, Latex, and I have been using computers for a very long time and ...
1
vote
1answer
9 views

Should Operating Systems Hide Sizes of Files/Folders the User is Denied Access to?

If there are files or folders the current user should be denied access to, should their sizes be displayed when the user asks, for example with the ls -l command on ...
1
vote
0answers
8 views

Concept of knots in B-splines

Given $n+1$ control points, B-spline blending functions are polynomials of degree $d-1$, ($1<d<=n+1$). This much is easy to comprehend. Now comes the part I am not able to make any sense ...
0
votes
0answers
5 views

How do I “tell” a simple perceptron/adaline neural netrork its output can't be negative?

I have made and trained a simple neural network which now seems to produce outputs reasonable in all the aspects but one: it gives negative values from time to time even though the outputs are always ...
3
votes
1answer
17 views

Negative numbers in Subset-Sum

If I have a set $A$ with positive and negative numbers, and a number to find C. It is possible to reduce the problem to one with only positive numbers in set $A$? I mean, it is possible to find a ...
1
vote
0answers
14 views

Explanation of algorithms used by NAS benchmark kernels

I'm not sure if this is the appropriate forum for asking the following question. Please guide me to the right forum. I am trying to understand the algorithms used by kernels(such as Integer Sort) in ...
-1
votes
0answers
7 views

What's the difference between on-line compression and off-line compression?

I am reading a paper, which introduce an on-line compression algorithm. Can anyone explain to me what's the difference between the on-line and off-line compression. I am looking forward for your ...
0
votes
0answers
12 views

Reference request: OpenMP and MPI [on hold]

I have been learning C programming for over a year. Now I wish to learn parallel programming concepts and principles and learn the use of OpenMP and MPI. Given my exposure, how should I begin? Some ...
0
votes
0answers
15 views

What is linear relaxation in the context of bayesian networks?

To add onto the question, how are elliptical differential equations applicable in this context? I was listening to a talk about Bayesian networks and someone asked if they were using differential ...
3
votes
1answer
46 views

What does it mean for a random number generator's sequence to be only 1-dimensionally equidistributed?

Whilst reading up on Xorshift I came across the following (emphases added): The following xorshift+ generator, instead, has 128 bits of state, a maximal period of 2^128 − 1 and passes BigCrush: ...
7
votes
1answer
48 views

NP Problems with unique solution

Is there any class of NP problems that have one unique solution? I'm asking that, because when I was studying cryptography I read about the knapsack and I found very interesting the idea.
4
votes
1answer
41 views

$NP\subseteq TIME[O(n^{\log n})]$

Is it more plausible that $NP\subseteq TIME[O(n^{\log n})]$ than $NP\subseteq P$? I don't see this mentioned much and is there a reason why? If this question doesn't make sense, explain why.
2
votes
1answer
35 views

parsing at semantic level due to ambiguities

I have a VHDL elaboration engine/simulator. As I understand it, the language syntax allows for ambiguities at syntax level. That is, an assignment ...
4
votes
0answers
44 views

Expressiveness of modern regular expressions

I recently discussed with a friend about a website that proposed regex challenges, mainly matching a group a of words with a special property. He was looking for a regex that matches strings like ...
0
votes
0answers
36 views

Prove that it is undecidable whether a Deterministic LBA accepts an infinite number of inputs [on hold]

Deterministic Linear Bounded Automaton (LBA) is a single-tape TM that is not allowed to move its head past the right end of the input (but it can read and write on the portion of the tape that ...
4
votes
0answers
29 views

Edge cuts with vertex weights

I have a problem in which I need to find an optimal graph cut that maximizes an objective over vertices (versus edge weights). I have looked at the literature but have not been able to find any ...
0
votes
1answer
43 views

Odd Parity Function [on hold]

I am trying to define a Odd Parity Function that takes three 1 bit inputs and will output a 1 if the 3 bits are odd as a Boolean function. ...
1
vote
2answers
38 views

In RSA, must $p$ and $q$ have the same number of bits?

Is it necessary to take the same bit size of "p" and "q" in case of RSA algorithm? i had read that bitsize of p and q must be same. BUT after calculating, i found that bit size could be different ...
-1
votes
0answers
16 views

Did i corrent prune using alpha/beta with BFS? [on hold]

Can i use alpha beta pruning with BFS? if a viable alternative to dfs or not? Many thanks.
-1
votes
0answers
33 views

Classifying a language [on hold]

Can I please have a good, detailed explanation on context free grammars, regular, recursive, recursively enumerable, and not recursively enumerable languages. Please keep In mind I am really knew with ...
1
vote
2answers
44 views

Can a self-learning appliance be developed?

I have heard of machine learning systems that can learn from trials of data what effect it should have, but I was wondering is it possible to make a learning appliance that builds on past data? ...
2
votes
2answers
28 views

Clock page replacement algorithm - Already existing pages

When simulating the clock page replacement algorithm, when a reference comes in which is already in memory, does the clock hand still increment? Here is an example: With 4 slots, using the clock ...
1
vote
0answers
23 views

Is object oriented programming fundamentally different than imperative programming? [duplicate]

I have been using C for a while, for some reasons I learnt C++. I can't see why object oriented is a "new" feature. For me an object is just a structure, and a set of functions which have a pointer ...
1
vote
1answer
33 views

Searching for a string of numbers in sequence

How would one search for a string of digits in a large digit sequence? For example, I'd like to search for 351814 in euler's number. I'm not too keen on computer science, I'm a pure math major, so I ...
0
votes
1answer
26 views

Maximum number of configurations on a TM that decides the language $A_\text{NFA}$ [on hold]

Consider a Turing Machine $M$ that decides the following language: $$A_{\text{NFA}} = \{ \langle N,w \rangle | N\text{ is an NFA and }N\text{ accepts }w \}.$$ Based on its input size, if $M$ wants to ...
2
votes
1answer
28 views

Chomsky normal form: epsilon rule

I have pretty simple question, but still can't find an answer just googling it. I'm trying to understand Chomsky Normal Form (CNF). There are three production rules: $A \to BC$ $A \to \alpha$ $S ...
0
votes
0answers
28 views

Marriage algorithm that maximizes number of pairings

I have a bipartite graph similar to the marriage problem, where there are M males and N females, and a 1:1 matching between males and females is desired (with the remainder of the more populous gender ...
2
votes
1answer
16 views

Wagner Fischer Algorithm and the Empty String

In the Wagner Fischer algorithm to calculate the Levenshtein distance for two input strings, the first step is to compare each input string with the empty string for each input. Why is this step ...
1
vote
0answers
21 views

Conjecture about a matrix column swapping challenge problem

So here is the challenge problem statement: https://icpcarchive.ecs.baylor.edu/index.php?option=com_onlinejudge&Itemid=8&page=show_problem&problem=1512 Basically, given a 0/1 matrix, you ...
2
votes
1answer
47 views

FOL substitution - is it possible to substitute two variables with each other? e.g. $\theta=\{x/y,y/x\}$?

Let $C = m(P,X,Y) \leftarrow m(Q,X,Z), m(R,Z,Y)$. Is it possible to do the following substitution? $D = C\theta$ where $\theta = \{Q/R,R/Q\}$ s.t. $D = m(P,X,Y) \leftarrow m(R,X,Z),m(Q,Z,Y)$
1
vote
2answers
45 views

Is there a decidable algorithm to compose two well-behaved recursive functions that work on a recursive tree datatype?

Let the following datatype be defined: data T = A | B T | C T T That is, B, B T, B (B T), C A A, C (B T) A and so on all are ...
-2
votes
0answers
11 views

Fixing Clock Skew By Adding Delays While Minimizing The Cost [on hold]

![When designing hardware devices, certain signals – especially clock signals – need to physically arrive at multiple different devices at exactly the same time. If they don't, the devices can get out ...
1
vote
1answer
21 views

Is Simon's problem a good NP-intermediate candidate?

We know that $BPP \subseteq BQP$ but we have no proof $BPP \subset BQP$ (Though we have the proof that BQP $!=$ BPP with an oracle) Since Simon's problem (as factoring) it's easily solvable by a ...
2
votes
1answer
34 views

How to reduce MAX-2SAT problem to finding a cut in a graph

I'm trying to reduce the MAX-2SAT problem to finding a cut in a graph, with no luck so far. Let me first show a description of the problem: 2SAT: Given a boolean formula $\varphi$ in a CNF form, where ...
1
vote
1answer
25 views

Small-step semantics: for-loops

I'm trying to construct the small-step semantic rules involving the for-loops, but I can't find anything about it in the literature (only about while-loops). I was wondering if anyone could help me ...
2
votes
2answers
49 views

What is the point of Löwenheim–Skolem theorem?

Theorem states Let $\phi$ be a sentence of predicate logic such that for any natural number $n \geq 1$, there is a model of $\phi$ with at least $n$ elements. Then $\phi$ has a model with ...
-2
votes
0answers
26 views

How i can find novel machine learning algorithms? [on hold]

Is there any machine learning algorithm from 2010 to now for classification that is useful and popular.I want to use this learning algorithm for pattern classification. I need a novel method with high ...
-2
votes
0answers
21 views

How to find the shortest common element between two sets generated by a grammar? [on hold]

Suppose I define two grammars: A = N | L (L A) B = N | L (L (L B)) Where A and B are recursive definitions, so ...
1
vote
0answers
14 views

Why does packet data don't need trailer/footer while frame needs it?

Why does packet don't need trailer/footer while frame needs it? I am trying to understand networking concept regarding OSI & TCP/IP layering. I have googled a bit and it says that the footer in ...
0
votes
1answer
27 views

Do you know of a brute-force algorithm for optimizing polynomial expressions? [on hold]

For instance, given the polynomial expression $xy + x + y + 1$ it will output $(x+1)(y+1)$. Thanks!
0
votes
0answers
14 views

Rule Tree Question [on hold]

I was given the following assignment: http://imgur.com/GLKAlut I understand how to define the language but I'm having trouble figuring out how to draw the rule tree... Can anyone point me in the right ...
1
vote
1answer
15 views

Alternate definitions of enumeration machines

In my textbook, enumeration machines are defined as possessing a special write-only output tape, which they can write characters to, but not move the head of. When they hit the print state, the string ...
1
vote
2answers
40 views

How to determine if a state is a fixed point in a Hopfield network?

I have been reading a lot and I am still unsure of how to determine this. Let's say I have an initial binary state vector (1, 1, 1). How would I go about determining whether (1, 1, 1) is a fixed point ...
3
votes
2answers
36 views

Fast algorithm to find points on one side of hyperplane?

Given $n$ points $x_1, x_2, ..., x_n \in \mathbb{R}^k$, where $\mathbb{R}^k$ can be high dimensional. Is it possible to devise a fast algorithm (1) Preparation: first take the n points as an input, ...
-1
votes
1answer
14 views

Main difference between data mining and statistics? [on hold]

Still don´t get the differece between data mining, machine learning, KDD with statistics. I´m making my thesis for my bachelor degree on computer science as theoretical framework i need to define ...

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