From 01ba01763b81a838dcbac4c08243804e068495b9 Mon Sep 17 00:00:00 2001 From: Preston Pan Date: Fri, 31 May 2024 15:05:34 -0700 Subject: add many things; remove useless files --- journal/20240530.org | 21 +++++++++++++++++++++ journal/20240531.org | 11 +++++++++++ mindmap/Kirchhoff's Laws.org | 35 +++++++++++++++++++++++++++++++++++ mindmap/differential equation.org | 26 ++++++++++++++++++++++++++ mindmap/lrc_circuit_source.png | Bin 0 -> 3271 bytes 5 files changed, 93 insertions(+) create mode 100644 journal/20240530.org create mode 100644 journal/20240531.org create mode 100644 mindmap/Kirchhoff's Laws.org create mode 100644 mindmap/differential equation.org create mode 100644 mindmap/lrc_circuit_source.png diff --git a/journal/20240530.org b/journal/20240530.org new file mode 100644 index 0000000..cf5e2da --- /dev/null +++ b/journal/20240530.org @@ -0,0 +1,21 @@ +#+TITLE: Daily Journal +#+STARTUP: showeverything +#+DESCRIPTION: My daily journal entry +#+AUTHOR: Preston Pan +#+HTML_HEAD: +#+html_head: +#+html_head: +#+options: broken-links:t +* Thursday, 30 May 2024 +** 00:49 +I am currently trying to optimize my emacs workflow more, as I realize that my NixOS configuration is quite complete. +After Kanata is added, my NixOS configuration covers almost every usecase; on the other hand, there are many small annoyances +within emacs that are persistent, such as the lack of RSS feeds, the lack of good snippets for LaTeX editing, the lack +of grammar checking and spell checking, and the lack of consistent autocomplete and the awkwardness of how new buffers +open in panes. Additionally, mu4e is not configured for my email account. + +I will then use this emacs configuration to edit my mindmap more in tandem with the configuring. I've already added many new +articles. +** 16:59 +I successfully improved my emacs configuration by a lot, and I'm going to keep on making the editing much more +streamlined. diff --git a/journal/20240531.org b/journal/20240531.org new file mode 100644 index 0000000..1994806 --- /dev/null +++ b/journal/20240531.org @@ -0,0 +1,11 @@ +#+TITLE: Daily Journal +#+STARTUP: showeverything +#+DESCRIPTION: My daily journal entry +#+AUTHOR: Preston Pan +#+HTML_HEAD: +#+html_head: +#+html_head: +#+options: broken-links:t +* Friday, 31 May 2024 +** 03:42 +I can't sleep. This is quite painful. diff --git a/mindmap/Kirchhoff's Laws.org b/mindmap/Kirchhoff's Laws.org new file mode 100644 index 0000000..be20a41 --- /dev/null +++ b/mindmap/Kirchhoff's Laws.org @@ -0,0 +1,35 @@ +:PROPERTIES: +:ID: 1d586d6b-bd97-4c59-ad57-8894ae4ac8ba +:END: +#+title: Kirchhoff's Laws +#+author: Preston Pan +#+html_head: +#+html_head: +#+html_head: +#+options: broken-links:t + +* Introduction +Kirchhoff's Laws, along with Ohm's law, create the axioms of circuit analysis. The two laws are the Kirchhoff Voltage Law +(KVL) and Kirchhoff's Current Law (KCL). They can be derived from an approximation of [[id:fde2f257-fa2e-469a-bc20-4d11714a515e][Maxwell's Equations]]. +** KCL +:PROPERTIES: +:ID: 9f7e61fa-a6ed-4d9b-8cdf-7f4ffdd80f06 +:END: +Due to the [[id:a871e62c-b4a0-4674-9dea-d377de2f780b][continuity equation]] for electrodynamics, current is always conserved locally. In an ideal one-dimensional +wire, the surface integral can be reduced to a simple line integral, given the current only moves in one direction +(which we will assume for circuits). +\begin{align} +\int I \cdot d\vec{l} = -\frac{\partial Q_{enc}}{\partial t} +\end{align} +If the total amount of charge in the wires are conserved: +\begin{align} +\label{} +\int \vec{I} \cdot d\vec{l} = 0 +\end{align} +Therefore: +\begin{align} +\label{} +\sum_{n}I_{n} = 0 +\end{align} +where the total current $\vec{I}$ can be decomposed into many currents of each branched path $I_{n}$. +** KVL diff --git a/mindmap/differential equation.org b/mindmap/differential equation.org new file mode 100644 index 0000000..8229587 --- /dev/null +++ b/mindmap/differential equation.org @@ -0,0 +1,26 @@ +:PROPERTIES: +:ID: 4be41e2e-52b9-4cd1-ac4c-7ecb57106692 +:END: +#+title: differential equation +#+author: Preston Pan +#+html_head: +#+html_head: +#+html_head: +#+options: broken-links:t +* Introduction +A differential equation is an equation whose solutions are functions and which incorporate derivatives of the function +you're solving for. Differential equations often have a family of infinite solutions, where a general solution for +a differential equation incorporates many particular solutions. Particular solutions to differential equations are specific +functions, corresponding to a single choice of an initial value problem. Therefore, general solutions tell you how to solve +initial value problems. + +Differential equations are often used to model real world systems, and are the main tool in numerical simulations of said +systems. +** ODE +An ODE is a differential equation involving single variable function solution classes and their derivatives. +** PDE +A PDE is a differential equation involving multivariable function solution classes and generally involve partial derivatives +of the unknown function. +** initial value problem +An initial value problem is a problem where one is given a differential equation and particular values of the unknown function +and particular values of its derivatives, and the result is a particular solution. diff --git a/mindmap/lrc_circuit_source.png b/mindmap/lrc_circuit_source.png new file mode 100644 index 0000000..efaca54 Binary files /dev/null and b/mindmap/lrc_circuit_source.png differ -- cgit