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## Meaning of the C in the unit "mg C L-1"

Could somebody tell me what the "C" signifies in the unit mg C L-1? I was wondering if it stood for concentration but it seems redundant as litres are mentioned. Thanks. The paper which use

earth-science

## Minimal complexity for pairing two comparable sets with comparability restrictions

A project at university (whose deadline has passed by now) presented the following problem: Consider two finite sequences of (not necessarily distinct) real numbers $a_1,\ldots,a_n$ and ...

computer-science

## Was there an attempt to make reusable regular expressions?

In everyday practice I often encounter tasks which would benefit from being able to define aliases for chunks of regular expressions to reuse them later. Typical examples include: parsing a floating .

computer-science

## If $T(n+1)=T(n)+\lfloor \sqrt{n+1} \rfloor$ $\forall n\geq 1$, what is $T(m^2)$?

$T(n+1)=T(n)+\lfloor \sqrt{n+1} \rfloor$ $\forall n\geq 1$ $T(1)=1$ The value of $T(m^2)$ for m ≥ 1 is? Clearly you cannot apply master theorem because it is not of the form ...

computer-science

## Which complexity class $3^{n/3}$

Assuming a problem has complexity $O(3^{n/3})$, Which is its class of complexity ? Despite that it is not as $2^{n}$ ,we can say is an exponential ?

computer-science

## Regular expression syntax

am a little confused by regular expression to convert to NFAs. am actually test using http://www.regexr.com/ but some of regular expression like a*+ab is that mean (a*)+ is that correct ..

computer-science

## 3/2 - Approximation probabilistic algorithm for MAX-3-COLOR

I have a textbook question here regarding Max-3-Coloring and need some assistance with it. I have searched for any type of information regarding it but haven't found anything substantial. Here is the

computer-science

## Are two non-Turing-recognizable languages closed under union?

If I have two languages that aren't Turing-recognizable, is the union between them always not T-recognizable? Why?

computer-science

## Kleene closure, concatenation problem

If $L_1 = \emptyset$ , $L_2= \{a\}$ then what is $$L_1\cdot L_2^* \cup L_1^*$$ The answer given is $\{\epsilon\}$ but I think it should be $\{\epsilon,a\}$. My Approach : $L_1^* = \{\epsilon\}$ ...

computer-science

## Min-Max number of shifts and reductions in bottom-up parser

Given the Grammar has no unit or ɛ-productions, What is minimum & maximum number of shifts and reduce needed by bottom-up parser?

computer-science

## Magic box problem [on hold]

You have an input array of size m*n. Each cell in the array is populated with either P or T. The only operation you can do on the array is flip columns. When you flip a column, the letters in all the

computer-science

## Learning Hierachial representation of objects in a unsupervised manner

I am trying to understand how the how a hierarchal representation of an object can be learned in a unsupervised manner, using the method described in this paper. ...

computer-science

## Graph Partition Across Cluster - Minimize Largest Matrix Size

I am writing some code for modeling semi-biologically realistic neural networks, which is to be run/distributed across nodes in a computer cluster. I begin with a very large adjacency matrix ...

computer-science

## Are all components compatible with each other? [on hold]

I'm new to building circuits. I have a simple project in mind, but I am not sure what components to buy. I am familiar with building computers and how the compatibility varies from hardware to ...

computer-science

## What happened if we implement quicksort without tail recursion?

On Wikipedia, it said that The in-place version of quicksort has a space complexity of O(log n), even in the worst case, when it is carefully implemented using the following strategies:

computer-science

## Unsplittable flow in capacitated networks

I have an undirected network with capacitated links/edges. Between some nodes unsplittable traffic has to be routed. All demands and capacities are known, but it is uncertain if all flows can be ...

computer-science

## When making a decision, how many "choices" are there?

Suppose I put a coin on a table. I can do this in two ways: heads up or heads down. Question: How many choices do I make? It looks like I have one choice in the sense of having one decision....

english-language

mathematics

## Comma usage: City and State / Full Date

Can we eliminate the comma after "2014" and "Indiana" below? The year and state are not parenthetical, and besides, the comma slows down the flow of the sentence. I think the two s

english-language

## 'Have both' -not sure I'm using this correctly

Is this correct? Have both of today’s meetings been cancelled?

english-language

## Difference between "at" and "in" when specifying location

I am used to saying "I am in India.". But somewhere I saw it said "I am at Puri (Oriisa)". I would like to know the differences between "in" and "at" in the ab

english-language