Notes, summaries, assignments, exams, and problems for Electronics

1. Task Constraints in Real-Time Systems

In real-time systems, task constraints refer to the limitations or requirements that must be met for timely and correct execution. The key constraints include:

• Time constraints (hard and soft deadlines)
• Precedence constraints (task dependencies)
• Resource constraints (limited CPU, memory)
• Synchronization constraints (shared resource management)

Failing to meet these constraints can result in system failure in critical applications like aircraft control and medical monitoring systems.

2. EDD (Earliest Due Date) Algorithm Explained

The EDD (Earliest Due Date) algorithm is used for aperiodic task scheduling, where tasks are executed in order of their deadlines. The task having the earliest due date is given the

Unit 12

Visitor: Hello there. I’m thinking of buying a USB flash drive and I’ve heard you’re presenting a new device at this show. Could I see it?

Salesperson: Of course. This is the new Dragon flash drive, a compact flash memory drive that acts like a portable hard drive.

Visitor: And what’s the storage capacity?

Salesperson: Well, this model here can hold 16 gigabytes of data. We also have drives of 64 gigs, but they’re more expensive. The drive consists of a USB connector covered by a removable cap, a mass storage controller, and a flash memory chip. It also includes a write-protect switch and password protection.

Visitor: You’re getting a bit too technical for me! Does it connect like a normal drive?

Salesperson: Yes, you just plug... Continue reading "Dragon Flash Drive and MP4 Player: Features and Comparison" »

Pumping Lemma and Non-Regular Languages

9) Define Pumping Lemma. Prove that the language L = { aⁱ b^j | i > j } is not a regular language:

Let L be a regular language. There exists a constant k such that for every string ω in L, where the length of string ω i.e |ω| ≥ k, we can break ω into 3 strings i.e ω = xyz following conditions:

• (i) |xy| ≤ k
• (ii) y ≠ ε i.e |y| > 0
• (iii) for each q ≥ 0, xy^qz ∈ L

Let L be a regular language. w = a^(k+1) b^k is a long string (given k > 0). |w| = 2k + 1, w = xyz should satisfy:

• (i) |xy| ≤ k
• (ii) y ≠ 0
• (iii) for each q ≥ 0, xy^q z ∈ L

Let k = 3, w = a⁴ b³, which is aaaaabbb.

• (i) |xy| ≤ k, 3 ≤ 3
• (ii) y ≠ 0, y = a

Minimization of DFA's

11) Minimization of DFA’s A=(Q, Σ, δ, q₀, F):

Use... Continue reading "Pumping Lemma, Table Filling, DFA Minimization, Parse Trees, Ambiguous Grammars & Context-Free Grammars" »

Counterpoint System Codes

• SVC AVINST: 1010349
• AV FREIGHT: 1012348
• INTERNATIONAL FREIGHT: 1002100
• ORDER HOLD: 1103013
• 30 DAY WARRANTY: 1010447
• 60 DAY WARRANTY: 1010450
• 90 DAY WARRANTY: 1010451
• 1 YEAR WARRANTY: 1010448
• 2 YEAR WARRANTY: 1126476
• 3 YEAR WARRANTY: 1010449
• CHANGE ORDER: 1106948
• CHANGE ORDER – CR: 1134105
• AV RESTOCK / RETURN FREIGHT: 1129446
• SVC AGMNT/MAINT: 1010346
• AV PRICE ADJUST: 1102227
• SVC PRICE ADJUST: 1102208
• COST ADJUST AV: 1102319
• COST ADJUST SVC: 1102321
• TAX ADJUST: 1104916
• 1000 OFFSET (SALE): 1103132
• 6000 OFFSET (SERVICE DEPT): 1103305
• 9000 OFFSET (AV DEPT): 1121772
• AV SVC AGMNT -1: 1103132
• AV SVC AGMNT OFFSET: 1137139
• AV SVC DIFF OFFSET -1: 1137989
• SERVICE TICKET HOLD: 1128671
• AV TECHNICAL REPAIR: 1137141
• SVC CONTRACTOR DIFF: 1121527
• INSTALLATION

Mobile Phones

Comprehension (4 points)

1. 1) No, because dangerous effects have not been shown conclusively.
2. 2) Because they used the phone while they were driving.

1. 3) True… advanced features are packed into extremely light and tiny models (lines 5-6).
2. 4) True… mobile phones can be a serious threat to health, for children in particular (line 7).
3. 5) False… what for many people is a useful device can be a nuisance for others (line 11).
4. 6) False. Some people even claim that… (lines 12-13).

Use of English (3 points)

1. 7) Luxury (l.1)
2. 8) Light (l. 6)
3. 9) Sickness, illness, disease
4. 10) Headache, backache, stomach-ache… toothache, heartache
5. 11) She said: “We’ll go and get some food.”
   She said they/we would go and get some food.
6. 12) I asked my father to

English Vocabulary Acquisition

How Children Learn Word Meaning

Children are always acquiring and building up their L1. They must find out which things can be packaged together under a label.

Knowing a Word: Types of Knowledge

Knowing a word involves different types of knowledge. The importance is how it is pronounced.

Factors Affecting Vocabulary Learning

• Demonstrability: Can the meaning be easily shown? (e.g., car = transport)
• Similarity: Is it similar to known words? (e.g., equal)
• Brevity: Is it a short or long word?
• Regularity of Form / Learning Load: Does it follow typical patterns? (e.g., bedroom)
• Opportunism: Is the word relevant to the child's immediate situation?
• Centres of Interest: Are words likely to be of relevance to the child's interests?

Key Concepts in Language Acquisition and Child Development

Questions & Answers

1. According to Chomsky, language is... A (We possess an innate capacity for language.)
2. Which of the following statements is true? C (Learners need a supportive environment.)
3. Behaviorism relies on... A (Skinner's theory of operant conditioning.)
4. According to Krashen... C (Comprehensible input is important.)
5. According to constructivism... A (Children of a similar age think similarly.)
6. The term "concentration span" refers to... A (The time and capacity for focused attention.)
7. Comprehensible input means... B (The teacher uses facial expressions and gestures.)
8. Language acquisition does not require... D (All of the above.)
9. What is the zone of proximal development? A (The zone

To control by PWM requires 2 factors:

1-crossing detection signal by 0.

2-? determine the time, every time you walk by 0.

to detect the zero crossing can be performed
through an operational amplifier connected
comparator.

TCA = 785

Pin Symbol Function

1 GND Earth

2 Q2 *Output 2 Inverted

3 Output U QU

4 Q1 * Output 1 Inverted

5 5Synchronizing voltage Vsync (to detect

zero crossing)

6 Inhibitor

7 QZ Z Output

8 8 Vref voltage stabilized (continuous signal for the

integrator)

9 9 ramp resistor R9 (for the integrator)

10 C10 ramp Capacitance (for the integrator)

11 11 V11 Control Voltage (for comparator)

12 12 C12 pulse Extension

13 LLong pulse

14 Q1 Output 1

15 Q2 Output 2

16 l sSupply voltage.

Preprocessing the Dataset

a. Normalize the Text

Python

import re
from nltk.tokenize import word_tokenize
import nltk
nltk.download('punkt')

# Preprocessing Function
def preprocess(text):
    text = re.sub(r'[^a-z\s]', '', text.lower())
    return word_tokenize(text)

# Apply Preprocessing
df['Processed'] = df['Sentence'].apply(preprocess)
print(df)

GPT-2 Text Generation

Python

from transformers import pipeline

# Load GPT-2 Model for Text Generation
generator = pipeline('text-generation', model='gpt2')

# Generate Text for a Given Prompt
prompt = "Once upon a time"
result = generator(prompt, max_length=50,
    num_return_sequences=1)
print(result[0]['generated_text'])

GPT-2 for AI Prompts

a. Prompt 1 - Future of AI

Python

prompt = "What is the future

When past simple and while past continuous. Used to: affirmative - S+used to+v.ing, negative - S+didn't use to+inf, interrogative - Did+S+use to+inf? Yes, I did. No, I didn't. Active Voice: Subject+verb+D.C.+Complement

Passive Voice: Subject+verb+D.C. (by)+Complement

Modals

• can/can't -> puede/no puede
• could/couldn't -> podía/no podía
• should/shouldn't -> debería/no debería -> consejo
• must -> deber -> obligación
• mustn't -> no deber -> prohibición
• have to -> tener que
• don't have to -> no tener que -> no obligación
• may -> puedo que
• might -> podía ser que -> posibilidad

Reported Speech

• now -> then
• today -> that day
• tomorrow -> the next day/the following day
• yesterday -> the previous day/the day before
• next