In English , we use " both of " , " both " for two things   for instance , if you are going out for a meal , there are two possible restaurants, you Say :   both restaurants are very good   Or,   both of the restaurants are very good   what is the difference?
What is the correct form in the following sentences, "both" and "both of them"?      a) "Both of them are unique."      b) "Both are unique."   If "both" by itself already contains "both of them", so I can conclude that the first option is not correct. Isn't it?
In CSS what is the difference between "." and "#" when declaring a set of styles? What is the difference between # and . when declaring a set of styles for an element and what are the semantics that come into play when deciding which one to use? First order differential equations with 2 varriables Does anybody know how to solve the following differntial equation?  $$w^2\cdot r+\frac{dw}{dt}\cdot r+\frac{dr}{dt}\cdot w=3g$$  where w and r are a function of time so $w(t)$ and $r(t)$. $g$ is a constant  EDIT: This equation came from a thought problem of mine which I will now explain since I still do not know how to approach the problem.  Basically I want to design a spiral track in which a vehicle will accelerate. However the total acceleration needs to be constant.   The vehicle will have 2 acceleration components, a radial component ($a_r$) and a change in speed component ($a_s$). Since we want constant acceleration: $a_r + a_s = constant$  From circular motion we know that $a_r = \omega ^2 r$ where $r$ is the radius, and $\omega$    Further we know that $v=\omega*r$, therefore: $a_s=\frac{d}{dt}(\omega r)$  For constant acceleration $a_{total} = a_r + a_s = \omega ^2 r + \frac{d}{dt}(\omega r) =constant$  Further usefull information: Length of the track covered at a certain time $l=v*t=\omega r t$  With all this the radius will be a function of time, $r(t)$ and the angular velocity will be a function of time, $\omega (t)$  Boundary conditions: $r(0)  = 0$ $\omega (0) = 0$  Now I would like to find a possible set of solutions to create a track by implementing end boundary conditions that i choose e.g. $v(t_{end})=100 [m/s]$ and $l(t_{end})=5000 [m]$  Here is a diagram for clarity: List the files accessed by a program time is a brilliant command if you want to figure out how much CPU time a given command takes.  I am looking for something similar that can list the files being accessed by a program and its children. Either in real time or as a report afterwards.  Currently I use:  #!/bin/bash  strace -ff -e trace=file "$@" 2&gt;&amp;1 | perl -ne 's/^[^"]+"(([^\\"]|\\[\\"nt])*)".*/$1/ &amp;&amp; print'   but its fails if the command to run involves sudo. It is not very intelligent (it would be nice if it could only list files existing or that had permission problems or group them into files that are read and files that are written). Also strace is slow, so it would be good with a faster choice. Calculating peaks in DEM using GRASS I know that the Linux kernel supports TRIM as of version 2.6.33, so there should be TRIM support in ubuntu.  Is TRIM enabled by default or do I need to change some settings or install additional software for it to work? If so, how? Why are hard drives never as large as advertised? From all the hard drives I have bought, they never seem to be as large as the advertised size; from 320 GB down to 290 GB, from 500 GB down to 450 GB, etc. Is there a technical reason for this? how to sort by the day of the week? I have two files.  file1:  Dave 734.838.9800   Bob 313.123.4567   Carol 248.344.5576   Mary 313.449.1390   Ted 248.496.2204   Alice 616.556.4458      file2:  Bob Tuesday   Carol Monday   Ted Sunday    Alice Wednesday   Dave Thursday     Mary Saturday     I merged the two files.  file3 should look like this:  Name      On-Call     Phone   Carol     MONDAY      248.344.5576   Bob       TUESDAY     313.123.4567   Alice     WEDNESDAY   616.556.4458   Dave      THURSDAY    734.838.9800   Nobody    FRIDAY      634.296.3356   Mary      SATURDAY    313.449.1390   Ted       SUNDAY      248.496.2204     But I cannot get the weekdays to be in order. How do I go about doing that? How can I ask a person in which order in his family among the siblings? My colleague he have two brothers. I want to know, he is first/second/third son of his parents, ie., the order in the family among their siblings.  I can simply ask     Are you first son of your family?   It simply give some predictions, I don't want to that.  Is there a better way to ask the question? LaTeX/BibTex not arranging citations by order of appearance I am having an issue with LaTex/Bibtex presenting my citations in order of appearance. I know there a plenty of questions on this and I have read some of them, but the solutions posted don't seem to do me any good. I am using MacTeX and TeXmaker.  I am writing a large document, like a Thesis. Chapters are split between individual Tex files and included using the \include command.  I have a large .bib file that is maintained by Mendeley (program I use for storing my references and producing a BibTex file).  I am using the package, cite (mainly for doing references like [1-3,6,9])  I have a pretty standard looking document.  \documentclass[11pt,a4paper]{report} \setcounter{secnumdepth}{3} \setcounter{tocdepth}{3} \newcommand{\doubleSignature}[3][Alex Mason]{% \parbox{\textwidth}{ \centering #3 \today\\ \vspace{2cm}  \parbox{7cm}{   \centering   \rule{6cm}{1pt}\\    #1  } \hfill \parbox{7cm}{   \centering   \rule{6cm}{1pt}\\   #2 } } } \usepackage[utf8]{inputenc} \usepackage{amsmath} \usepackage{amsfonts} \usepackage{amssymb} %\usepackage[sorting=none]{biblatex} %\bibliography{Alex} % Where journals.bib and phd-references.bi \usepackage[pdftex]{graphicx} \usepackage{enumerate} \usepackage{nomencl} \usepackage{wasysym} \usepackage{booktabs} \usepackage{cite} \usepackage[left=1in,right=1in,top=1in,bottom=1in]{geometry} \graphicspath{{./Diagrams/}} \usepackage[labelfont={sf,bf}, margin=1cm]{caption} \usepackage{subcaption} \renewcommand{\figurename}{Fig.} \renewcommand{\tablename}{Tab.} \renewcommand{\bibname}{References} \author{NAME (MEng)} \title{TITLE} \date{\today} \makenomenclature %------------------------------------------------ \begin{document} \maketitle \pagenumbering{roman} %-----------------------------------------------certificate of originality----------------      -------------------------------------------- \input{CertofOrigin} \begin{abstract} ABSTRACT \end{abstract} %-----------------------------------------------contents------------------------------------------------------------ \tableofcontents \listoffigures \addcontentsline{toc}{chapter}{List of Figures} \listoftables \addcontentsline{toc}{chapter}{List of Tables} \chapter*{Acknowledgements} \addcontentsline{toc}{chapter}{Acknowledgements} ACKNOWLEDGEMENTS \printnomenclature[1.5in] \addcontentsline{toc}{chapter}{Nomenclature} \pagebreak \pagenumbering{arabic} \include{2ndYearReport_CHAP1} \include{2ndYearReport_CHAP2} \include{2ndYearReport_CHAP3} \bibliographystyle{unsrt} \bibliography{Alex} %\printbibliography \end{document}   The goofy looking part at the top (\newcommand{doubleSig.....) is just for when i input a special page I made containing a certificate of originality spiel with two boxes for signatures and my university logo.  As you can see I am using the standard bibtex way of doing bibliographies by stating the style then the stating the bib file to use right at the end of the document. I have tried biblatex but can't get it to work. It says it hasn't produced the bib file but doesn't really state why.  As far as I am aware everything was working A-OK until I started on the second chapter and began adding citations in there. Now my citations are all messed up and won't correct. My first citation starts with [9]!!!  [1] appears in a figure caption later down the page, after 10, 11 and 12 have been called!  I have tried deleting all the working files (bbl, aux, log etc) but nothing happens. I get the same result. IIRC I used to have this problem with MS Word and is part of the reason why I switched to LaTex...yet it seems to have followed me!   bibtex does through a few warnings when it runs stating that some references are missing journal names or volume numbers. Would that be a reason?  What have I done wrong with my code? Laravel 4.1 Run migrations and update configuration from package dependencies Delete hiberfil.sys on Windows 7 Ok, so I know what hiberfil.sys is, and I want to use hibernation on my laptop.  But I have another hard drive active in my laptop, it's taken from my old one... and I want to get rid of the hiberfil.sys on that drive. But even with admin privileges I can't delete it.  Any ideas? Long lay over in Seoul. Do I need a visa as a Filipino citizen? I'm a Filipino immigrant from USA about to visit home in December.  I have a 14-hour lay over in Seoul,  South Korea.  Do I need a visa to leave the airport to do a little sightseeing? Simple Past vs. Present Perfect: "was" vs. "has been" Possible Duplicate:          As a English non-native speaker it is difficult for me to understand when I must use present perfect or past simple because in my official language there isn't the present perfect tense. I know that present perfect is related to something that happened in the past but its result is important now. But for instance:        The message has been sent.   The message was sent.      Please help me point me out any examples/contexts where I should use 1. instead of 2. I was readng Wikipedia article (English one) about radiation pressure because there is something I still cannot figure out. As I understand it, radiation pressure emerges from conservation of momentum. Photons or electromagnetic waves possess momentum and when they are absorbed, reflected or even emitted, the aborber/reflector/emitter experiences a pressure that is proportional to the irradiance (in watts per square meter). OK. In the case of a perfect reflector that does nothing but reflecting incoming radiation, it would seem the reflector is pushed and the radiation is reflected in opposite directions. But the radiation has not lost anything, it has only changed direction. And I do not understand how something can be set in motion (the reflector), which amounts to do work, yet the source of this work does not lose energy. I mean, if the radiation, after a U turn, meets a second reflector, it would have pushed two reflectors a way, yet it would continue in its original direction as if nothing happened...? What am I missing here? Should not photons lose something? Dollar Sign corrupts question In  my question () contains a "$" in a quoted section of the question.  Originally I had a second "$" in a second quoted  section of the same question.    However when I did this the second $ seemed to trigger a style that made the text italic and lost spacing between words.  I took out the second "$" and instead emphasized it with the word "dollars" which solved the immediate problem.  However, in the listing of the question, (not the question itself) the same thing happens after the first "$".  The summary shows the text without spaces between words and in italic.  Seems like a bug.  Below is a verbatim copy/paste of the original issue (two dollar signs):    I was able to find a small ESC for about $12 off of ebay.  If you were designing a robot, would you see that and think?       $12 bucks for an ESC that connects to simple pulse-wave interface -   sign me up!   Or would you think:     $12 just to control a motor? I could throw together an H-bridge for   $0.50 and be done with it.   My robot in particular actually has two motors and therefor $24 to control the two of them.  But the interface is really easy (plus has the added advantage of being R/C vs computer controlled with a simple change of connectors.  Which way would you go? Temporal Table that doesn't use system time We want to implement temporal tables in SQL Server 2016. We are creating a Datawarehouse and developing Type 2 Slowly changing Dimension Tables.  For the BeginDate, we want it to be dependent on transaction date and not the current getdate time. We are reprocessing a history of transactions. Example below, customer has gym or bank status, and goes from inactive, to active, or pending, dependent on transaction date.  We currently have this.  CREATE TABLE dbo.Department (     CustomerId int primary key,     MembershipStatus int,     TransactionDate datetime  );   We we would like to create a table like this.  CREATE TABLE dbo.DepartmentHistory (     CustomerId int primary key,     MembershipStatus int,     TransactionDate datetime,     BeginDatetime datetime,     EndDatettime datetime  );   Example usage would be:   first Customer Transaction on 3/5/2018 as Pending P        +------------+--------+-----------+---------+     | CustomerId | Status | BeginDate | EndDate |     +------------+--------+-----------+---------+     | 1          | P      | 3/5/2018  | NULL    |     +------------+--------+-----------+---------+    second transaction is 4/21/2018 is Active A        +------------+--------+-----------+-----------+     | CustomerId | Status | BeginDate | EndDate   |     +------------+--------+-----------+-----------+     | 1          | P      | 3/5/2018  | 4/21/2018 |     | 1          | A      | 4/21/2018 | NULL      |     +------------+--------+-----------+-----------+ Avoid large spaces between text and equations I use the options  \renewcommand{\baselinestretch}{1.25} \setlength{\parskip}{0pt} \setlength{\parindent}{0pt}    in the preamble of my document and most of the time the document looks like intended. Once in a while though, especially when I use multiline-equations, I get huge spaces right before and after the equation and the surrounding text, for example:    Is there any way I can avoid that without removing the \parskip option? Does mathematics become circular at the bottom? What is at the bottom of mathematics? I am trying to understand what mathematics is really built up of. I thought mathematical logic was the foundation of everything. But from reading a book in mathematical logic, they use "="(equals-sign), functions and relations.  Now is the "=" taken as undefined? I have seen it been defined in terms of the identity relation.  But in order to talk about functions and relations you need set theory.  However,  seems to be a part of mathematical logic.  Does this mean that (naive) set theory comes before sentential and predicate logic? Is (naive)set-theory at the absolute bottom, where we can define relations and functions and the eqality relation. And then comes sentential logic, and then predicate logic?  I am a little confused because when I took an introductory course, we had a little logic before set-theory. But now I see in another book on introduction to proofs that set-theory is in a chapter before logic. So what is at the bottom/start of mathematics, logic or set theory?, or is it circular at the bottom?  Can this be how it is at the bottom?  naive set-theory $\rightarrow$ sentential logic $\rightarrow $ predicate logic $\rightarrow$ axiomatic set-theory(ZFC) $\rightarrow$ mathematics  (But the problem with this explanation is that it seems that some naive-set theory proofs use logic...)  (The arrows are of course not "logical" arrows.)  simple explanation of the problem:  a book on logic uses at the start: functions, relations, sets, ordered pairs, "="  a book on set theory uses at the start: logical deductions like this: "$B \subseteq A$", means every element in B is in A, so if $C \subseteq B, B \subseteq A$, a proof can be "since every element in C is in B, and every element in B is in A, every element of C is in A: $C \subseteq A$". But this is first order logic? ($(c \rightarrow b \wedge b \rightarrow a)\rightarrow (c\rightarrow a)$).  Hence, both started from each other? Assistive technology not found AWTError $ java -jar aprof-plot.jar Exception in thread "main" java.awt.AWTError: Assistive Technology not found: org.GNOME.Accessibility.AtkWrapper     at java.awt.Toolkit.loadAssistiveTechnologies(Toolkit.java:807)     at java.awt.Toolkit.getDefaultToolkit(Toolkit.java:886)     at java.awt.Toolkit.getEventQueue(Toolkit.java:1734)     at java.awt.EventQueue.invokeLater(EventQueue.java:1264)     at aprofplot.Main.newWindow(Main.java:33)     at aprofplot.Main.main(Main.java:359)   Possible explanations I saw here was to install Java-access-bridge. But I am unable to install libaccess-java-bridge. Countable or uncountable; family of disjoint triangles? If we say that $\mathcal{S}$ is a family of disjoint triangles on a plane, is $\mathcal{S}$ a countable or an uncountable set?  I believe that it is an uncountable set since $\mathbb{R}$ is uncountable and our triangles' corner coordinates are $\in \mathbb{R}$, but I cannot prove this formally, any tip would help.