OpenLLM-France/wikimedia huggingface dataset:
# Circuit Theory/Time Constants

Homogeneous equations are exponential. A homogeneous differential equation is discharging or charging (0 value constant DC source). A non-homogeneous differential equation has a sinusoidal source. It can be solved by splitting into a homogeneous solution plus a particular solution. The steady state solutions earlier were particular solutions.
    homogeneous equation ⇒ discharging (DC source) ⇒ homogeneous solution
    non-homogeneous equation ⇒ AC source ⇒ particular (steady state) + homogeneous (discharging) solution
The proof of the exponential solution to the discharging circuit is is hard:
* guess solution
* see if it is possible
* if possible assume it is the solution
In this case it works because there is only one guess:
that we know of.
A first order differential looks like this:
    $g(t)+\tau {\frac {dg(t)}{dt}}=0$
A solution is:
    $g(t)=e^{-{\frac {t}{\tau }}}$ (Gödel proved that there are always other truths possible. We can not be certain this is the only solution.)
Tau, τ, or $\tau$ has a name:
    $\tau$ = time constant
The Steady State(particular) definition is:
    $t\geq 5*\tau$
since for charging and discharging:
    $1-e^{-5}=.9933,e^{-5}=0.0063$
Try to write all answers in the form of
    $g(t)=e^{-{\frac {t}{\tau }}}$
instead of:
    $g(t)=e^{number*t}$
The reason is: looking at a number and taking the inverse of it is hard. This makes it hard to look at an equation and "see" it's time constant.
The units of any time constant are seconds. In circuits with both inductors and capacitors, there are two time constants that are called "zeros". They are called zero's because they are solutions to the particular solution which sets the differential to zero. They are given the symbol "s" and are identical to the complex frequency concept.
# Circuit Theory/Transform Domain
## Impedance

Let's recap: In the transform domain, the quantities of resistance, capacitance, and inductance can all be combined into a single complex value known as "Impedance". Impedance is denoted with the letter Z, and can be a function of s or jω, depending on the transform used (Laplace or Fourier). This impedance is very similar to the phasor concept of impedance, except that we are in the complex domain (laplace or fourier), and not the phasor domain.
Impedance is a complex quantity, and is therefore comprised of two components: The real component (resistance), and the complex component (reactance). Resistors, because they do not vary with time or frequency, have real values. Capacitors and inductors however, have imaginary values of impedance. The resistance is denoted (as always) with a capital R, and the reactance is denoted with an X (this is common, although it is confusing because X is also the most common input designator). We have therefore, the following relationship between resistance, reactance, and impedance:
[Complex Laplace Impedance]
    $Z=R+jX$

## Susceptance and Admittance

The inverse of resistance is a quantity called "Conductance". Similarly, the inverse of reactance is called "Susceptance". The inverse of impedance is called "Admittance". Conductance, Susceptance, and Admittance are all denoted by the variables Y or G, and are given the units Siemens. This book will not use any of these terms again, and they are just included here for completeness.

## Parallel Components

Once in the transform domain, all circuit components act like basic resistors. Components in parallel are related as follows:
    $Z_{1}||Z_{2}={\frac {Z_{1}Z_{2}}{Z_{1}+Z_{2}}}$

## Series Components

Series components in the transform domain all act like resistors in the time domain as well. If we have two impedances in series with each other, we can combine them as follows:
    $Z_{1}{\mbox{ in series with }}Z_{2}=Z_{1}+Z_{2}$

## Solving Circuits

This section of the Circuit Theory wikibook is a stub. You can help by expanding this section.
# Circuit Theory/Transients

Transient analysis produces an equation of voltage or current.

## Energy Imbalance

The temporary conditions are caused by an energy imbalance. The energy imbalance occurs between power sources and capacitors or inductors. Power sources may charge capacitors or inductors. The capacitors or inductors may dump previously stored energy into resistors, each other or charge power sources.
Transients occur while energy is being balanced in the circuit.

## Transient Origins

The events that can cause transients are:
* switching on power
* changing a component's value in a functioning circuit
* discharging a component after the circuit has been turned off
Turning a knob can change a value, but so can temperature, light, acceleration, stretching, compressing, humidity, etc. Electrical transducers sense non-electrical energy and cause resistance, capacitance or inductance values to change or change the energy stored in a capacitor/inductor.

## First & Second Order Analysis

First order circuits have either a capacitor or inductor.
Second order circuits have two energy storage elements and require a different analysis technique.
First order transients voltages and currents are typically one sinusoidal riding one exponential.
Second order transients are typically described as one of the following:
* overdamped
* critically damped
* underdamped
* undamped
The word "damped" refers how two different types of energy storage elements (capacitors and inductors) interact as energy is dissipated. The math in general shows the combination of two sinusoidals riding on two exponentials.

## Math Summary

There are two ways to solve transient problems.

#### Differential Equations

Something causes the energy imbalance. The goal is to find the final value of a charging circuit, not the equation describing how energy was added to the circuit.
The goal is to find an equation for the discharge. The steps are to form a differential equation (no integrals at any step) and evaluate constants. Differential equation analysis requires computing a constant C. Unfortunately, C = 0 in most of the examples below. This is because the equation describes time from 0 to ∞. At t=∞, most designs want all energy eliminated from a circuit.
# Circuit Theory/Thevenin-Norton
## Vth using Node

    $V_{th}=6.4516$

## In using Node

    $I_{N}=1.064773736$

## Rth or Rn

    $V_{th}/I_{N}={\frac {6.4516}{1.064773736}}=6.0591ohms$

## Finding Rth using source injection and node

* zero sources to find Rth
* add source injection since parallel/series combinations do not exist
* redraw up and down before solving
Here is the mupad/matlab code that generates the answer R$_{th}$ = 6.0591 ohms.

## Comparing Node with Thevenin Equivalent

Solving the node equations yields:
    $V_{a}=5.393$
    $V_{b}=1.1673$
    $V_{c}=1.107$
    $i_{12}=0.3571$
    $v_{12}=4.286$
Using the Thevenin equivalent (and voltage divider) to compute voltage across the 12 ohm resistor:
    $v_{12}=V_{s}*{\frac {12}{R{total}}}$
    $v_{12}=6.4516*{\frac {12}{6.0591+12}}=4.287$
So they match ...
Thevenin voltage and resistance can not be computed from a node analysis of the entire circuit, but the node analysis of the entire circuit can be used to check if the thevenin equivalent produces the same numbers.
# Circuit Theory/Transients Summary and Study guide

This cover the basics of transients, the analysis of circuit response that goes away after a long time.

## RC or LC Circuits

General solution steps for RL and LC circuits with a voltage source (with out voltage source Vc=0):
* Use KVL and KCL, get 1st order differential equation
* Find particular solution (Forcing Function) $Y_{p}$ (Table is at bottom of page)
* The complete solution is the particular + the complementary.
$y(x){=}Y_{p}+y_{c}$
$y_{c}(x){=}K_{1}+K_{2}e^{sx}$
* Substitute solution into differential equation to find $K_{1}$ and s. (Or find $K_{1}$ by solving in steady state.)
* Use the given initial conditions to find $K_{2}$
* Write final solution

## RLC Circuits

* DC circuits -> constant forcing functions
* AC circuits -> sinusoidal forcing functions
* Particular solution for VDc =>L-> SC, C-> OC
| Concept | Formula | notes |
| Damping Coefficiant (series LC) | $\alpha {=}{R \over 2L}$ | |
| Damping Coefficiant (parallel LC) | $\alpha {=}{1 \over 2RC}$ | |
| Undamped resonant frequency | $\omega _{0}{=}{1 \over {\sqrt {LC}}}$ | |
| General Form | $f(t){=}{d^{2}i(t) \over dt^{2}}+2\alpha {di(t) \over dt}+\omega _{0}^{2}i(t)$ | |
| Characteristic equation | $s^{2}+2\alpha s+\omega _{0}^{2}{=}0$ | |
| Roots Characteristic eqn | $s_{1,2}{=}-\alpha \pm {\sqrt {\alpha ^{2}-\omega _{0}^{2}}}$ | |
| Damping ratio | $\zeta {=}{\alpha \over \omega _{0}}$ | |
| Overdamped | $x_{c}(t){=}K_{1}e^{s_{1}t}+K_{2}e^{s_{2}t}$ | roots real and distinct $\zeta >1$ $\alpha >\omega$ |
| Critically damped | $x_{c}(t){=}K_{1}e^{s_{1}t}+K_{2}te^{s_{1}t}$ | roots real and equal $\zeta {=}1$ $\alpha {=}\omega$ |
| Natural Frequency | $\omega _{n}{=}{\sqrt {\omega _{0}^{2}-\alpha ^{2}}}$ | |
| Underdamped | $x_{c}(t){=}K_{1}e^{-\alpha t}\cos {\omega _{n}t}+K_{2}e^{-\alpha t}\sin {\omega _{n}t}$ | roots complex $\zeta <1$ $\alpha <\omega$ |

## Table of Forcing functions

| Value | Approximation |
| Cons. | A |
| $e^{t}$ | $Ke^{st}$ |
| sin(t)/cos(t) | $A\sin(pt)+B\cos(pt)$ |
| $t^{n}$ | $At^{n}+Bt^{n-1}+...+Ct+D$ |
| $t^{n}e^{t}$ | $At^{n}e^{pt}+Bt^{n-1}e^{pt}+...Ce^{pt}$ |
# Circuit Theory/Transistor symbols
## Circuit symbols

There are lots of different types of transistors. The most popular is a MOSFET and within this family there are lots of possibilities. The goal right now is not to understand the differences and what all the lines mean. Look at them and see that normally there are three wires associated with them.
| | | | | | P-channel |
| | | | | | N-channel |
| JFET | MOSFET enh | MOSFET enh (no bulk) | MOSFET enh (no bulk) | MOSFET dep |
# Clock and Data Recovery

This is a reference textbook for readers that desire to complete and to render systematic their knowledge on this subject.
This book provides the electronic engineer with the knowledge of:
    - what the CDR function and structure are
    - where a CDR is used in a communication network
    - the mathematical models (just three!) needed to understand the CDR operation (no matter how complex its actual implementation is!).
Prior knowledge of calculus and some experience with Fourier and Laplace transforms are required.
* Introduction
** Definition of (phase) jitter
** Jitter is far from sinusoidal..
** Models can only be linear..
** Acquisition, tracking and jitter performances
* Buffer Memory (Elastic Buffer)
** Clock domains
** Cascades of Buffers and CDRs, delays and tolerance
** Burst and Continuous transmission modes
* Structures and types of CDRs
*** The CDR' amplifier/filter
*** The CDR phase comparator
*** The CDR Phase and Frequency Detector PFD
*** The CDR' VCO
** Examples
** The jitter tolerance function
** The noise spectrum is shaped by the PLL structure
** 1st order (type 1) loop
*** Applications of the 1st order type 1 architecture
** 2nd order type 1 and 2 (slave) loops
*** 2nd order type 1
**** Applications of the 2nd order type 1 architecture
*** 2nd order type 2
**** Applications of the 2nd order type 2 architecture
* Miscellanea
* Conclusion
# What Is a Web Application?

A web application is an application which shows its output in a browser ("client") and which interacts with data which are managed by another program, a "web server", which is usually executed on another computer (when we test it we may have both the client and the server on the same machine).
Websites like Google, Yahoo! Mail, Facebook, Twitter, Amazon, and also CMS platforms (such as WordPress, Joomla, Drupal) and online games like "Might & Magic", "Forge of Empires" or "Seafight" all provide web applications.
In their oldest form, web applications were CGI scripts, and Harbour provides a class to use this protocol (see https://github.com/harbour/core/blob/master/contrib/hbtip/cgi.prg) and an example showing how to employ a class to (https://github.com/harbour/core/blob/master/tests/html.prg).
http://www.harbour-project.com.br/samples/testcgi.html and see the side box at http://gnosis.cx/publish/programming/harbour.html
The first six chapters of a book describing CGI programming can be downloaded from http://www.cgi101.com/book/, and a straightforward description of the thing can be read at http://www.whizkidtech.redprince.net/cgi-bin/tutorial.
There is a tentative for providing FastCGI in Harbour, see https://github.com/hernad/harbour-fastcgi.
CGI, however, is old and obsolete and the reasons are explained here: https://www.perl.com/article/perl-and-cgi/#why-not-to-use-cgi. This page is in the Perl website, as CGI and Perl have been strongly (even if improperly) associated.
The web server Apache contains needs mod_cgi or mod_perl to run CGI scripts, likewise we can use mod_harbour from https://github.com/FiveTechSoft/mod_harbour.
blog live demo: https://harbour.fourtech.es/modharbour_samples/blog/index.prg and its Full source code: https://github.com/FiveTechSoft/mod_harbour/tree/master/samples/blog
https://github.com/JoseluisSanchez/MVC_Harbour
An alternative to using Apache is downloading DBFree from http://www.dbfree.org/home.msp?XY=11421849
# Design of Main Memory Database System/Recovery

* Checkpointing
* Fault Tolerance
* Preventing Data Corruption
Recovery in DBMS means recovering the database. That is restoring the database to a state that is known to be consistent after some failure that makes the database inconsistent.
There are many things which can go wrong in a database environment. The following sections discuss about most important failure modes
* Hard Disk Failure
* Process Failure - software errors
* System Failure - power loss
# Design of Main Memory Database System/Storage Engine Overview

Table of Contents — Previous: Storage Engine — Next: Database Management
Chapter 4: Storage Engine Overview
Storage engine usually takes care of data organization, access methods and transactions in Database Management Systems (DBMS). This is the lowest subsystem in DBMS that interacts with operating system services. Generally, products interact through OS Layer subsystem (wrapper to OS system calls) to ease the porting effort.
Data shall be stored in one of the following components of the computer system
* Memory
* Secondary Storage - Disk
* Tertiary storage - Tape
These components have data capacities, cost per byte, speed ranging over many orders of magnitude. Devices with smallest capacity offer the fastest access speed and have the highest cost per byte.
Current Trend:Tertiary storage are now replaced by disks because of its huge capacity and low cost per byte. Future Trend: Disks are replaced by main memory because of its increase in capacity and decrease in cost per byte.
One disk block transfer takes approximately 5 milliseconds whereas main memory access takes 100 nanoseconds. By keeping the whole database in memory, these disk I/Os are converted to memory access, thereby improves the throughput by many-folds. Memory being a volatile devices losses the data stored in it, when the power goes off. But disk being a non-volatile device keeps the content intact even for long periods when there is a power failure. This makes main memory storage manager difficult to implement. It uses logging and checkpointing mechanisms to cope up with power failure and make the data stored in main memory persistant.
Table of Contents — Previous: Storage Engine — Next: Database Management
# Design of Main Memory Database System/Real world Implementation

This chapter takes you through the implementation of real world open source database management system. This project is hosted in sourcforge.net site.
You shall download the copy of the source code from
# Designing Professional Development
## Contents

METHODS
* Technology-Based Learning
* Coaching
* Just-in-Time Learning
* Internships & Mentorships
* Online Courses
* Communities of Practice
* Leadership
CASE STUDIES
* High Tech High, San Diego
* Costa Rica Teachers
* Teacher Tech Training, Singapore
* Prof Devel in South Africa
* OLPC in Ecuador-Peru
* Higher Education in U.S.
* Prof Devel in China
* Prof Devel in U.S. HealthCare
# Design of Main Memory Database System/Query Representation

* Query Algebra
* Parsing
* Query Tree
# Design of Main Memory Database System/Storage Engine

Part II: Storage Engine
* Chapter 4: Overview
* Chapter 5: Database Management
* Chapter 6: Allocator
* Chapter 7: Transaction Management
* Chapter 8: Concurrency Management
* Chapter 9: Recovery
* Chapter 10: Log
* Chapter 11: Table
* Chapter 12: Index
Table of Contents — Previous: Introduction to MMDB — Next: Storage Engine Overview
# Design of Main Memory Database System/Transaction

Table of Contents —
Chapter 7: Transaction Management
A transaction is basic unit of work that comprises many database operations. Transactions shall either be committed or rolled back. This means it shall decide whether to submit all the changes to DBMS or to neglet all the changes and take the database state to the state when that transaction started.

## Transaction Stages

For recovery purposes, DBMS should maintain the state of the transaction. A transaction state changes are given below
* Transaction Start
* Database operations (INSERT, UPDATE, DELETE, SELECT)
* Commit or Abort
Database operations include read and modifications of data records. The effect of running SELECT statement is read and effect of running INSERT, UPDATE and DELETE is data record modifications.
The commit operation informs the successful end of transaction to the transaction manager. After commit operation, database should be in consistent state and all the updates made by that transaction should be made permanent.
The rollback or abort operation informs the transaction manager that there is an error in one of the operations involved in the transaction and database is in inconsistent state. All the updates made by the transaction must be undone on the database to get it back to the previous consistent state; that is state at which the transaction started.

## Transaction pseudo code for money transfer

BEGIN TRANSACTION;
Read account1 balance
If read failed GOTO UNDO;
Reduce Rs 100 from account1 balance
If reduce failed GOTO UNDO;
Read account2 balance
If read failed GOTO UNDO;
Add Rs 100 to account2 balance
If add failed GOTO UNDO;
COMMIT;
GOTO FINISH;
UNDO:
ROLLBACK;
FINISH:
RETURN;

## Transaction Properties

Transaction processing guarantees four important properties (referred as ACID properties)
Atomicity — Each transaction is treated as all or nothing- it either commits or aborts. If a transaction commits, all its effects remain. If it aborts, all its effects are undone.
Consistency — Transactions preserve data consistency; it always takes the database from one consistent state to another consistent state. Intermediate state shall be inconsistent, but commit or rollback operation should again take the database to another new consistent state or to the old consistent state.
Isolation — Transactions should be isolated from one another. Even though all transactions run in parallel, updates made by one transaction should not be visible to other and vice versa until the transaction commits.
Durability — Transaction commit should ensure that its updates are present in the database, even if there is a subsequent system crash.

## Correctness Principle

If a transaction executes in the absence of any other transaction or system error, and it starts with the database in a consistent state, then the database is also in a consistent state when the transaction ends. This means that if we control simultaneous transactions and system errors, transactions always ensure correctness.The former is controlled by concurrency manager and the later is controlled by logging and recovery manager.
# Calculus/Infinite Limits/Infinity is not a number/Solutions

Write out an explanatory paragraph for the following limits that include $\infty$. Remember that you will have to change any comparison of magnitude between a real number and $\infty$ to a different phrase. In the second case, you will have to work out for yourself what the formula means.
$\lim _{x\to \infty }{\frac {1}{x^{2}}}=0$
${\frac {1}{x^{2}}}$
${\frac {1}{x^{2}}}$
$\sum _{n=0}^{\infty }2^{-n}=1+{\frac {1}{2}}+{\frac {1}{4}}+{\frac {1}{8}}+\cdots =2$
$\sum _{n=0}^{i}2^{-n}$
$i$
$\sum _{n=0}^{i}2^{-n}$
$i$
Navigation:
Main Page · Precalculus · Limits · Differentiation · Integration · Parametric and Polar Equations · Sequences and Series · Multivariable Calculus · Extensions · References
# Calculus/Integration
### Basics of Integration

4.1 Definite integral
4.2 Fundamental Theorem of Calculus
4.3 Indefinite integral
4.4 Improper Integrals

### Integration Techniques

4.5 Infinite Sums
4.6 Derivative Rules and the Substitution Rule
4.7 Integration by Parts
4.8 Trigonometric Substitutions
4.9 Trigonometric Integrals
4.10 Rational Functions by Partial Fraction Decomposition
4.11 Tangent Half Angle Substitution
4.12 Reduction Formula
4.13 Irrational Functions
4.14 Numerical Approximations
4.15 Exercises

### Applications of Integration

4.16 Area
4.17 Volume
4.18 Volume of Solids of Revolution
4.19 Arc Length
4.20 Surface Area
4.21 Work
4.22 Center of Mass
4.23 Pressure and Force
4.24 Probability
Navigation:
Main Page · Precalculus · Limits · Differentiation · Integration · Parametric and Polar Equations · Sequences and Series · Multivariable Calculus · Extensions · References
# Diablo Canyon Nuclear Power Plant: The WikiBook/orphaned pages/Public official interventions

AP National Writer Jeff Donn broke a story June 23, 2011 asserting that due to leaks of radioactive tritium from at "three-quarters" of U.S. NPP's, three U.S. senators asked for a congressional investigation, or a Government Accountability Office investigation, of nuclear power plant safety and regulation, putatively based upon results of an Associated Press investigation. The Senators are
* Barbara Boxer of California, chairs the Senate Committee on Environment and Public Works
* Sheldon Whitehouse of Rhode Island
* Bernard Sanders of Vermont
The AP report also contends that:
* leaks of radioactive water are "undetected for years [and are] are not going to stop"
* 75% of high rad waste an NPP's are pooled, whereas at DCPP that figure is at 81%

## The New Jersey Oyster Bay angle

The article quotes Janet Tauro, co-founder of Grandmothers, Mothers, and More for Energy Safety near the Oyster Creek, N.J. NPP expressing the point of view that the NRC is "a very closed regulatory agency."
At the GAO, similar demands were brought by New Jersey Senators
* Frank R. Lautenberg
* Robert Menendez

## GAO meeting

On Tuesday June 21, GAO hearings, other speakers included Ed Markey of Massachusetts and Peter Welch of Vermont, who also complained about the alleged leaks.
The article acknowledges, however, that "the NRC has said it disagrees with AP's conclusions" and the Nuclear Energy Institute blasted the report as "selective, misleading reporting".
The AP report also notes that 66 of 104 American nuclear reactors have been relicensed and sixteen are pending.
Despite such assurances, safety activists are laying plans to mobilize the public.
"Now it's mothers and housewives who are concerned about fallout from Fukushima and from reactors in their own neighborhood," Gunter said.
According to the AP report, NJ State Assemblyperson Annette Quijano is "drafting a legislative resolution asked [sic]for stronger federal oversight of the state's four commercial nuclear reactors". However, any such resolution would have no jurisdiction.
The report also indicates that the NRC is preparing a safety report for release in July and quoted Chairman Jaczko as recognizing that the Fukushima disaster was exacerbated by "power outages, spent fuel pools and emergency planning" issues.

## References

* ↑ http://www.sanluisobispo.com/2011/06/23/1654736/senators-demand-congressional.html#storylink=mirelated