OpenLLM-France/wikimedia huggingface dataset:
# Lesson 3.1: Case, Number, Gender, and Article

This lesson outlines the basics of case, number, gender, and article in Greek grammar. Greek pronouns, adjectives and articles must have endings that agree in case, number and gender, with the noun they describe.

## Case

In English, only pronouns have a case (i.e. I/me/my), but in Greek all nouns have a case. The Greek word for case is πτώσεις. The cases are usually formed by changing the ending of the noun. They help identify how a noun is being used in a sentence.
Ancient Greek had a separate case for direct objects (Accusative) and indirect objects (Dative), but modern Greek uses the Accusative case for both, except in some instances where the Genitive case is used for indirect objects.
In the following example, "the bag of the girl" could also be written "the girl's bag", but the form used below is closer to the way the Genitive case is used in Greek.

## Number

Just like in English, Greek nouns can either be singular or plural.

## Gender

Greek has three genders: masculine, feminine, and neuter.
Only in the case of animals or people does the grammatical gender correspond to the normal use of the word gender. For all other nouns, it is best to simply think of their gender as a way of classifying them into different categories.
Greek uses articles that are similar to those present in English. There are definite and indefinite articles in English, but Greek has definite articles only. In English, the definite article is: the (singular and plural, countable and uncountable). The definite article refers to a specific object or person. The indefinite articles are: a before a consonant or consonant sound and an before a vowel or vowel sound. The indefinite articles refer to a generic object or person. The definite articles in Greek are ο, η, and το. There is no indefinite article in Greek.

## Summary

This lesson introduced the concept of case, gender, number, and article in Greek. Case is a way of expressing the grammatical purpose of a noun. The cases in Greek are Nominative, Genitive, Accusative, and Vocative. Number is a way of identifying the quantity of a noun. Number can either be singular or plural. Gender is best seen as a way of categorizing nouns into groups. The genders in Greek are masculine, feminine, and neuter. An article is a way of further identifying how a noun is being used in a sentence. Greek has both a definite and indefinite article.

## Exercises

There are exercises available here.
Contents Lesson 1 • Lesson 2 • Lesson 3 • Lesson 4 • Lesson 5 • Lesson 6 • Lesson 7 • Lesson 8 • Lesson 9 • Lesson 10 Vocab 1 • Vocab 2 • Vocab 3 • Vocab 4 • Vocab 5 • Vocab 6 • Vocab 7 • Vocab 8 • Vocab 9 Alphabet • Grammar Credits
# Pinyin/Fear

See also
# Pinyin/Feared

See also
# Pinyin/Fat-soluble

Special:search/fat prefix:Pinyin/
# Pinyin/Father

See also
Father is a male parent.
fuhqin shih narnxihng d fuhmuu.
# Pinyin/Fat

Special:search/fat prefix:Pinyin/

## Noun

* zhifarng

## Adjective

* feir d
Fat is something found in foods, and it is the most concentrated kind of energy that a human can use. It has 9 kilocalories in one gram. The other two types of energy that humans can use are carbohydrates and proteins. Those each have 4 kilocalories in one gram. The human body uses the fat to make the body bigger. The human eats healthy things like vegetables can reduce fat.
Zhīfáng shì shíwù d chéngfèn, shì réntǐ kěyòng d 1-zhoong zuì nóngsuō néngliàng, yǒu 9 kcal/g. Qítā 2-zhoong, réntǐ kěyòng d néngliàng, shì tahnshuiiwuh hé dànbáizhí, gè yǒu 4 kcal/g. Zhīfáng shǐ réntǐ biàn pàng. Rénlèi chī jiànkāng d dōngxī rú shūcài, kě jiǎnshǎo zhīfáng.
# Pinyin/Father's Day

Search Pinyin day
Father's Day is a celebration honoring fathers. Many countries celebrate it on the third Sunday of June, but it is also celebrated on other days. Father's Day complements Mother's Day, a celebration honoring mothers.
Fuhqinjier shih gaanxieh fuhqin d jierrih. heenduo guorjia zaih Liuhyueh d dih-3'g Xingqirih qihngzhuh, yee yoou zaih qirta rih'zi qihngzhuh. torng Fuhqinjier duihyihng gaanxieh muuqin d shih Muuqinjier.
# Pinyin/Favorite

See also
# Pinyin/Fat person

Special:search/fat prefix:Pinyin/
# Pinyin/Fatigue

See also
Fatigue or tiredness, is a kind of physiological message. It is a kind of uncomfortable feeling of organisms, can be psychological or somatic. Short term fatigue is caused by over activity and the lack of rest, severe fatigue can be fatal. General opinion is that those who suffer from fatigue do not drive.
Tiredness is a natural response of the human body, if no matter how much rest still cannot recover, one should be aware if one suffer from 'chronic fatigue syndrome'.
Píjuàn huò píláo, shì shēnglǐ xìnhào de yīzhǒng. Shì shēngwù qízhōng yīzhǒng de bú shūfú gǎnjué. Dàzhì kě fēnwéi jīngshén shàng hé ròutǐ shàng. Duǎnqī de píjuàn tōngcháng shì yóuyú guòdù huódòng bìngqiě quēfá xiūxī suǒzhì, yánzhòng píjuàn huò kě zhìmìng. Yībān rènwéi píjuàn de rén bù shìyí jìnxíng jiàshǐ děng gōngzuò.
Píláo shì réntǐ de zìrán fǎnyìng, dànshì rúguǒ wúlùn zěnyàng xiūxī háishì wèinéng huīfù, jiù yīnggāi zhùyì shìfǒu huànshàng "mànxìng píláo zònghézhèng".
# Pinyin/Fault

See also
# Rebol Programming/font-sans-serif

FONT-SANS-SERIF is a string of value: "arial"
# DESCRIPTION:

Find a face's window face.
FIND-WINDOW is a function value.

# ARGUMENTS

* face -- (Type: object)
# DESCRIPTION:

Checks a flag in a VID face.
FLAG-FACE? is a function value.

# ARGUMENTS

* face -- (Type: object)
* flag -- (Type: any)
# DESCRIPTION:

Return FIRST of series, and increment the series index.
FIRST+ is a function value.

# ARGUMENTS

* word -- Word must be a series. (Type: word paren)

# (SPECIAL ATTRIBUTES)

* catch
# DESCRIPTION:

Sets a flag in a VID face.
FLAG-FACE is a function value.

# ARGUMENTS

* face -- (Type: object)
* flag -- (Type: any)
# DESCRIPTION:

Focuses key events on a specific face.
FOCUS is a function value.

# ARGUMENTS

* face -- (Type: any)

# REFINEMENTS

* /no-show
# Rebol Programming/font-fixed

FONT-FIXED is a string of value: "courier new"
# Rebol Programming/font-serif

FONT-SERIF is a string of value: "times"
# DESCRIPTION:

Returns the first value of a series.
FIRST is an action value.

# ARGUMENTS

* series -- (Type: series pair event money date object port time tuple any-function library struct event)
# DESCRIPTION:

Flashes a message to the user and continues.
FLASH is a function value.

# ARGUMENTS

* val -- (Type: any)

# REFINEMENTS

* /with
** face -- Center over this face (Type: any)
* /offset
** xy -- (Type: any)
# DESCRIPTION:

Returns a copy of the types of a function.
TYPES-OF is a function value.

# ARGUMENTS

* value -- (Type: any)
# DESCRIPTION:

Evaluates the block if condition is not TRUE.
UNLESS is a native value.

# ARGUMENTS

* condition -- (Type: any)
* block -- (Type: block)
# DESCRIPTION:

Returns a set with duplicate values removed.
UNIQUE is a native value.

# ARGUMENTS

* set -- (Type: series)

# REFINEMENTS

* /case -- Use case-sensitive comparison
* /skip -- Treat the series as records of fixed size
** size -- (Type: integer)
# DESCRIPTION:

Returns a value's datatype.
TYPE? is a native value.

# ARGUMENTS

* value -- (Type: any-type)

# REFINEMENTS

* /word -- Returns the datatype as a word.
# DESCRIPTION:

Removes the current key event focus.
UNFOCUS is a function value.
# DESCRIPTION

(undocumented) UNINSTALL is a function value.
# DESCRIPTION:

Unbinds words from context.
UNBIND is a native value.

# ARGUMENTS

* words -- A block of words or single word (returned) (Type: block any-word)

# REFINEMENTS

* /deep -- Include nested blocks
# DESCRIPTION:

Returns a copy of the path with any trailing "/" removed.
UNDIRIZE is a function value.

# ARGUMENTS

* path -- (Type: file string url)
# DESCRIPTION:

Creates a new set that is the union of the two arguments.
UNION is a native value.

# ARGUMENTS

* set1 -- first set (Type: series bitset)
* set2 -- second set (Type: series bitset)

# REFINEMENTS

* /case -- Use case-sensitive comparison
* /skip -- Treat the series as records of fixed size
** size -- (Type: integer)
# DESCRIPTION:

Returns TRUE if it is this type.
TYPESET? is a function value.

# ARGUMENTS

* value -- (Type: any-type)
# Practical Electronics/Circuits to make/MMC

The Modular Multifunction Counter or MMC is a custom device that combines several counting functions in a format that that is compact and highly extendable.
The functions performed by the MMC are:
* Binary/BCD
* Up/Down
* Presetable
* Resetable
* Able to be extended to an arbitrary number of digits
* Decoding and display of the counter
The MMC is a modular design, which means that it is made up of several components which can be interchanged to give different functionality. It is made up in two dimensions of blocks of three digits: the boards stack vertically for every block of three digits, performing all functions for those digits, while they also join horizontally for extension to larger numbers.
The bottom board of rightmost stack controls the settings for all digits to the left of it. By plugging a board in to the left-hand side of the bottom board, the new board automatically becomes a slave to the old board (all settings on the new board are overridden), and vice versa.
Each stack is made up of at least four boards:
* Settings - this board either allows the user to select the mode of counting or accepts settings from a master board and implements those.
* Counter - this board contains the 4029 counters and gives a BCD output.
* Decoder - this board takes the BCD from the 4029 counters and converts it to 7-segment inputs.
* Display - this board displays the decoded count.
Please bear in mind that the last two boards can be changed for something else, for example a board that outputs a binary number as a row of red or green LEDs.
Because of the large size, circuit diagrams and any notes on the design of the cicuit are located here.
PCB artwork and component layouts are available here. You will need Adobe Acrobat to read some of them. This is available at Adobe's website.
There is also a photo gallery.

## Improvements

If you think you can improve on any part of this circuit, please do not hesitate to contact User:Inductiveload to suggest it. This could be as small as a way to lose a jumper wire on a PCB or as large as a suggested new module option.
# Practical Electronics/Circuits Analysis/Superposition
## Superposition Principle

(a)
(b)
(c)
    Figure 1: The circuits showing the linearity of resistors.
Most basic electronic circuits are composed of linear elements. Linear elements are circuit elements which follow Ohm’s Law. In Figure 1 (a) with independent voltage source, V$_1$, and resistor, R, a current i$_1$ flows. The current i$_1$ has a value according to Ohm’s Law. Similarly in Figure 1 (b) with independent voltage source, V2, and resistor, R, a current i$_2$ flows. In Figure 1 (c) with independent voltage sources, V1 and V2, and resistor, R, a current i flows. Using Ohm’s Law equation 1 is reached. If some simple algebra is used then equation 2 is reached. But V$_1$/R has a value i$_1$ and the other term is i$_2$ this gives equation 3. This is basically what the Superposition Theorem states.
    $i={\frac {V_{1}+V_{2}}{R}}$(1)
    $i={\frac {V_{1}}{R}}+{\frac {V_{2}}{R}}$(2)
    $i=i_{1}+i_{2}\,$(3)
The Superposition Theorem states that the effect of all the sources with corresponding stimuli on a circuit of linear elements is equal to the algebraic sum of each individual effect. Each individual effect is calculated by removing all other stimuli by replacing voltage sources with short circuits and current sources with open circuits. Dependent sources can be removed as long as the controlling stimuli is not set to zero. The process of calculating each effect with one stimulus connected at a time is continued until all the effects are calculated. If kth stimulus is denoted sk and the effect created by sk denoted ek.
    $\sum _{k=1}^{N}e_{k}$(4)
The steps for using superposition are as follows:
    1. Calculate the effect of each source in turn with all other independent voltage sources short circuited and independent current sources open circuited.
    2. Sum these effects to get the complete effect.
Note: the removal of each source is often stated differently as: replace each voltage source with its internal resistance and each current with its internal resistance. This is identical to what has been stated above. This is because a real voltage source consists of an independent voltage source in series with its internal resistance and a real current source consists of a independent current source in parallel with its internal resistance.

### Superposition Example

    Figure 2: The circuit for the example.
Problem: Calculate the voltage, v, across resistor R$_1$.
Step 1: Short circuit V$_2$ and solve for v$_1$. By voltage divider rule.
    $v_{1}={\frac {V_{1}(R_{1}||R_{3})}{R_{2}+(R_{1}||R_{3})}}$(5)
Short circuit V$_1$ and solve for v$_2$. By voltage divider rule.
    $v_{2}={\frac {V_{2}(R_{1}||R_{2})}{R_{3}+(R_{1}||R_{2})}}$(6)
Step 2: Sum the effects.
    $v=v_{1}+v_{2}\,$
Using equations 5 and 6.
    $v={\frac {V_{1}(R_{1}||R_{3})}{R_{2}+(R_{1}||R_{3})}}+{\frac {V_{2}(R_{1}||R_{2})}{R_{3}+(R_{1}||R_{2})}}$
If $R_{1}=R_{2}=R_{3}=2k\Omega$ and $V_{1}=V_{2}=15V$ then
    $v={\frac {15(2k||2k)}{2k+(2k||2k)}}+{\frac {15(2k||2k)}{2k+(2k||2k)}}$
    $v={\frac {15(1k)}{3k}}+{\frac {15(1k)}{3k}}$
    $v=10V\,$
# Practical Electronics/Circuits Analysis/Two Port Network
## RC

    ${\frac {V_{o}}{V_{i}}}={\frac {\frac {1}{j\omega C}}{R+{\frac {1}{j\omega C}}}}={\frac {1}{1+j\omega T}}$
    $T=RC$
    $\omega _{o}={\frac {1}{T}}={\frac {1}{RC}}$
    This circuit has Stable voltage at low frequency therefore suitable for filtering low frequency therefore the name Low Pass Filter

## CR

    ${\frac {V_{o}}{V_{i}}}={\frac {R}{R+{\frac {1}{j\omega C}}}}={\frac {j\omega T}{1+j\omega T}}$
    $T=RC$
    $\omega _{o}={\frac {1}{T}}={\frac {1}{RC}}$
    This circuit has Stable voltage at high frequency therefore suitable for filtering high frequency therefore the name High Pass Filter

## LR

    ${\frac {V_{o}}{V_{i}}}={\frac {R}{R+j\omega L}}={\frac {1}{1+j\omega T}}$
    $T=RC$
    $\omega _{o}={\frac {j\omega L}{R+j\omega L}}={\frac {1}{1+j\omega T}}$
    This circuit has Stable voltage at low frequency therefore suitable for filtering low frequency therefore the name Low Pass Filter

## RL

    ${\frac {V_{o}}{V_{i}}}={\frac {R}{R+{\frac {1}{j\omega C}}}}={\frac {j\omega T}{1+j\omega T}}$
    $T={\frac {L}{R}}$
    $\omega _{o}={\frac {1}{T}}={\frac {1}{RC}}$
    This circuit has Stable voltage at high frequency therefore suitable for filtering high frequency therefore the name High Pass Filter

## LC - R

    ${\frac {V_{o}}{V_{i}}}={\frac {R}{R+j\omega L+{\frac {1}{j\omega C}}}}$
    Tuned Resonance Selected Band Pass Filter

## R - LC

    ${\frac {V_{o}}{V_{i}}}={\frac {j\omega L+{\frac {1}{j\omega C}}}{R+j\omega L+{\frac {1}{j\omega C}}}}$
    $T=RC$
    $\omega _{o}={\frac {1}{T}}={\frac {1}{RC}}$
    Tuned Resonance Selected Band Reject Filter

## LC// - R

    ${\frac {V_{o}}{V_{i}}}={\frac {R}{R+j\omega C+{\frac {1}{j\omega L}}}}$
    Tuned Resonance Selected Band Pass Filter

## R - LC//

    ${\frac {V_{o}}{V_{i}}}={\frac {j\omega C+{\frac {1}{j\omega L}}}{R+j\omega C+{\frac {1}{j\omega L}}}}$
    Tuned Resonance Selected Band Pass Filter
    Tuned Resonance Selected Band Pass Filter

## LR + CR

Transfer Function
    ${\frac {V_{o}}{V_{i}}}=({\frac {1}{1+j\omega {\frac {L}{R}}}})({\frac {j\omega RC}{1+j\omega RC}})$
Band Pass or band of frequencies that has a stable voltage
    ${\frac {R}{L}}-{\frac {1}{RC}}$ provided that ${\frac {1}{RC}}>{\frac {R}{L}}$
Band Pass Filter

## RC - RL

Transfer Function
    ${\frac {V_{o}}{V_{i}}}=$
Band Pass or band of frequencies that has a stable voltage
    ${\frac {1}{RC}}-{\frac {R}{L}}$ provided that ${\frac {R}{L}}>{\frac {1}{RC}}$
Band Pass Filter

## Summary
### Low Pass Filter

    ${\frac {V_{o}}{V_{i}}}={\frac {\frac {1}{j\omega C}}{R+{\frac {1}{j\omega C}}}}={\frac {1}{1+j\omega T}}$
    $T=RC$
    $\omega _{o}={\frac {1}{T}}={\frac {1}{RC}}$

### High Pass Filter

    ${\frac {V_{o}}{V_{i}}}={\frac {R}{R+{\frac {1}{j\omega C}}}}={\frac {j\omega T}{1+j\omega T}}$
    $T=RC$
    $\omega _{o}={\frac {1}{T}}={\frac {1}{RC}}$
# Practical Electronics/Common Problems
## it used to work, but no more

If it works once, most electronic devices will continue to work almost indefinitely. There are a few exceptions:
* nearly every electronic component will be permanently damaged or destroyed, if power or other connections are connected to something with a voltage too large to handle, or unexpectedly reversed. Designers often put a "protection circuit" -- such as a crowbar circuit -- between connectors and sensitive components. But with adequate protection, most components will last indefinitely:;
** transistors
** integrated circuits
** ceramic capacitors
** printed circuit boards
* Some things, even when used normally, will eventually wear out and stop working:
** primary batteries
** secondary batteries
** incandescent bulbs
** LED degradation: every LED (including the infrared LED in each opto-isolator) gradually gets dimmer and dimmer.
** aluminum electrolytic capacitors ("wet electrolytics").
** relays
High temperature and high current usually accelerates wear-out. Sometimes a heat sink can extend the life of a component.
# Practical Electronics/Circuits Analysis/Mesh Analysis
## Meshes

A 'mesh' (also called a loop) is simply a path through a circuit that starts and ends at the same place. For the purpose of mesh analysis, a mesh is a loop that does not enclose other loops.

## Mesh Analysis

Similar to nodal analysis, mesh analysis is a formalized procedure based on KVL equations. A caveat: mesh analysis can only be used on 'planar' circuits (i.e. there are no crossed, but unconnected, wires in the circuit diagram.)
Steps:
1. Draw circuit in planar form (if possible.)
2. Identify meshes and name mesh currents. Mesh currents should be in the clockwise direction. The current in a branch shared by two meshes is the difference of the two mesh currents.
3. Write a KVL equation in terms of mesh currents for each mesh.
4. Solve the resulting system of equations.

## Complication in Mesh Analysis

1. Dependent Voltage Sources
Solution: Same procedure, but write the dependency variable in terms of mesh currents.
2. Independent Current Sources
Solution: If current source is not on a shared branch, then we have been given one of the mesh currents! If it is on a shared branch, then use a 'super-mesh' that encircles the problem branch. To make up for the mesh equation you lose by doing this, use the mesh current relationship implied by the current source (i.e. $I_{2}-I_{1}=4mA$).
3. Dependent Current Sources
Solution: Same procedure as for an independent current source, but with an extra step to eliminate the dependency variable. Write the dependency variable in terms of mesh currents.

## Example

Given the Circuit below, find the currents $I_{1}$, $I_{2}$.
The circuit has 2 loops indicated on the diagram. Using KVL we get: Loop1: $0=9-1000I_{1}-3000(I_{1}-I_{2})$
Loop2: $0=3000(I_{1}-I_{2})-2000I_{2}-2000I_{2}$
Simplifying we get the simultaneous equations: $0=9-4000I_{1}+3000I_{2}$ $0=0+3000I_{1}-7000I_{2}$ solving to get: $I_{1}=3.32mA$ $I_{2}=1.42mA$
# Practical Electronics/Circuits to make/MMC/PCBs

This page contains links to the PCB artwork and component layouts for the MCC. It is arranged by board. Each PDF contains:
* The solder-side layout for making a PCB mask.
* The artwork showing copper tracks (red) and wire links (blue).
* The component layout and bill of materials.

## Directory of Files

** Board 1 - Settings Controller
** Board 2 - Counter Module
** Board 2 - Decoder Module
** Board 2 - Display and Output Module
# Practical Electronics/Crowbar circuit

A crowbar circuit is a method of protecting a circuit against high voltages (overvoltage) in the event of a power supply malfunction or power surge. This is especially useful in a device using TTL components as these are very sensitive to overvoltage. However, there are many other devices which can be damaged by overvoltage.
A crowbar circuit works by sensing a voltage that is above a certain threshold and shorting out the power supply. This causes a voltage drop in the rest of the circuit and current surge through the power supply that will trip a circuit-breaker or blow a fuse. The circuit must have a fuse or circuit-breaker, as without it the power supply or the crowbar circuit will be damaged. Crowbar circuits are so named because their activation is similar in effect to dropping a crowbar across bus bars (heavy duty power supply lines).
A typical crowbar circuit is as follows:
This crowbar circuit has an 8V power supply, and triggers at around 10v. To change the power supply rating, the zener diode, ZD1, needs to be changed to reflect the new trigger voltage. It should be about 1V higher than the nominal supply voltage.

## further reading

* Wikipedia: Crowbar_(circuit)
* Wikipedia: resettable fuse
* Wikipedia: thyristor
* Wikipedia: Schottky
* Wikibooks: Power Electronics#Triacs
# Practical Electronics/Circuits Analysis/Short connection

Short connection means a conducting wire has no resistance present.
# Practical Electronics/Collaboration Page
## Contributors

Add your name with ...... if you wish to get involved.
* Inductiveload 15:47, 5 August 2006 (UTC)
* Filip Dominec 19:21, 24 November 2006 (UTC) (collaboration with the czech project "Praktická elektronika")
* A.K.Karthikeyan 16:32 28 June 2008 (UTC)
* sanjay khedar 10:57 24 dec 2008 (UTC)
* Gowrav Gowda 04:57 4 feb 2013 (UTC)
* Encik Tekateki (discuss • contribs) 14:02, 6 February 2020 (UTC)
* Joshua Omaraye (Editor) 02:37, 08 March 2024 (UTC +1)
# Practical Electronics/Circuits to make

This part of Practical Electronics is a repository for circuits that have been made and tested, and can be made by you, using the diagrams presented here.
They range from simple plug-in modules for prototyping to more sophisticated modular counters and so on.