Friday 16 June 2023

 What is artificial intelligence (AI) ?

Introduction to AI

v  Definition and brief history of AI

Artificial Intelligence (AI) refers to the development of computer systems that can perform tasks that typically require human intelligence. It involves the creation of algorithms and models that enable machines to learn from data, reason, make decisions, and perform actions autonomously.

AI encompasses a wide range of technologies and techniques, including machine learning, deep learning, natural language processing, computer vision, robotics, and more. The field of AI aims to replicate human cognitive abilities, such as perception, understanding, reasoning, and problem-solving, in machines.

The history of AI dates back to the mid-20th century when researchers began exploring the concept of creating machines capable of intelligent behavior. Over the years, advancements in computing power, data availability, and algorithmic techniques have propelled the field forward, leading to significant breakthroughs and practical applications.

Machine learning is a fundamental aspect of AI. It involves training algorithms on large amounts of data, enabling them to recognize patterns, make predictions, and improve their performance over time. Deep learning, a subfield of machine learning, utilizes artificial neural networks inspired by the human brain's structure and function. These networks can learn complex representations and perform tasks such as image and speech recognition with remarkable accuracy.

AI has found applications in various industries and domains. In healthcare, AI algorithms can assist in diagnosing diseases, analyzing medical images, and personalizing treatment plans. In finance, AI is used for automated trading, fraud detection, and risk assessment. AI also plays a significant role in transportation, with the development of self-driving cars and traffic optimization systems.

While AI brings numerous benefits and opportunities, it also raises important ethical considerations. Issues such as bias in algorithms, privacy concerns, and the impact on the job market require careful attention. Ensuring the responsible development and deployment of AI systems is crucial to mitigate potential risks and ensure beneficial outcomes.

In conclusion, AI is a rapidly evolving field that aims to create intelligent machines capable of performing tasks that traditionally required human intelligence. It encompasses various technologies and techniques, including machine learning and deep learning, and has transformative potential across industries and domains. By harnessing the power of AI, we can unlock new possibilities and address complex challenges in our society.

 

v  Key concepts and terminology (machine learning, deep learning, neural networks, etc.)


    Here's an explanation of some key concepts and terminology related to AI:
 

1. Machine Learning (ML): Machine learning is a subset of AI that focuses on algorithms and models that allow computers to learn and make predictions or decisions without being explicitly programmed. ML algorithms learn from data, identify patterns, and make predictions or take actions based on that learning.

 2. Deep Learning: Deep learning is a subfield of machine learning that is inspired by the structure and function of the human brain. It involves the use of artificial neural networks with multiple layers (hence the term "deep") to learn and extract complex representations from data. Deep learning has achieved remarkable success in areas such as image recognition, natural language processing, and speech recognition.

 3. Neural Networks: Neural networks are computational models inspired by the structure and function of biological neurons in the human brain. They consist of interconnected nodes, called artificial neurons or "units," organized in layers. Each unit takes input, applies a mathematical operation, and produces an output. Neural networks can learn from data by adjusting the weights and biases of the connections between neurons, allowing them to recognize patterns and make predictions.

 4. Supervised Learning: Supervised learning is a type of machine learning where the algorithm learns from labeled examples or training data. The data includes input features and corresponding output labels or target values. The algorithm learns to map the input features to the correct output by generalizing from the training data. Common algorithms in supervised learning include decision trees, support vector machines (SVM), and neural networks.

 5. Unsupervised Learning: Unsupervised learning is a type of machine learning where the algorithm learns from unlabeled data. The algorithm explores the patterns and structures inherent in the data without any explicit guidance. It aims to discover hidden patterns, group similar data points, or reduce the dimensionality of the data. Clustering algorithms and dimensionality reduction techniques like principal component analysis (PCA) are examples of unsupervised learning.

 6. Reinforcement Learning: Reinforcement learning is a type of machine learning where an agent learns to interact with an environment to maximize a reward signal. The agent takes actions in the environment and receives feedback in the form of rewards or penalties. By learning from this feedback, the agent improves its decision-making policies to achieve its objectives. Reinforcement learning has been successful in applications such as game playing, robotics, and autonomous systems.

 7. Training Data: Training data is a set of examples used to train a machine learning model. It consists of input features and corresponding output labels or target values in the case of supervised learning. The quality and representativeness of the training data greatly influence the performance and generalization ability of the model.

 8. Feature Extraction: Feature extraction is the process of transforming raw data into a format that is more suitable and informative for machine learning algorithms. It involves selecting or engineering relevant features that capture important characteristics of the data. Feature extraction helps in reducing noise, dimensionality, and improving the learning process.

 9. Model Evaluation: Model evaluation is the process of assessing the performance and generalization ability of a machine learning model. It involves testing the model on a separate set of data, called the test set or validation set, and measuring various metrics such as accuracy, precision, recall, and F1 score. Model evaluation helps in determining how well the model is likely to perform on unseen data.

 These are just a few key concepts and terminologies in AI and machine learning. Understanding these concepts is essential for delving deeper into the field and exploring the applications and techniques within AI.

v  Real-world applications of AI

Here are some real-world applications of AI across various industries:

1. Healthcare:

   - Medical Diagnosis: AI algorithms can analyze medical images (e.g., X-rays, MRIs) and assist in diagnosing diseases like cancer, cardiovascular conditions, and eye disorders.

   - Drug Discovery: AI is used to analyze large datasets and identify potential drug candidates, accelerating the drug discovery process.

   - Personalized Medicine: AI can analyze patient data to develop personalized treatment plans and predict optimal drug dosage.

 2. Finance:

   - Fraud Detection: AI algorithms can detect patterns and anomalies in financial transactions, helping to identify and prevent fraudulent activities.

   - Risk Assessment: AI is used to analyze market trends, customer behavior, and other factors to assess investment risks and make informed decisions.

   - Chatbots and Virtual Assistants: AI-powered chatbots and virtual assistants are utilized for customer service, answering queries, and providing financial advice.

 3. Transportation:

   - Autonomous Vehicles: AI is crucial in self-driving cars, enabling them to perceive the environment, make decisions, and navigate safely.

   - Traffic Optimization: AI algorithms help optimize traffic flow, reduce congestion, and improve transportation efficiency.

   - Predictive Maintenance: AI can analyze sensor data from vehicles and predict maintenance needs, optimizing fleet management and reducing downtime.

 4. Retail:

   - Customer Recommendation Systems: AI algorithms analyze customer preferences and behaviors to provide personalized product recommendations.

   - Inventory Management: AI can forecast demand, optimize inventory levels, and automate supply chain processes, leading to cost savings and efficient operations.

   - Visual Search: AI enables image recognition and visual search capabilities, allowing customers to find products based on images rather than keywords.

 5. Manufacturing:

   - Quality Control: AI systems can inspect products for defects using computer vision, reducing manual inspection efforts and improving accuracy.

   - Predictive Maintenance: AI analyzes sensor data from machinery to detect anomalies, predicting maintenance needs and minimizing downtime.

   - Process Optimization: AI algorithms can optimize production processes, improving efficiency, and reducing costs.

 6. Education:

   - Adaptive Learning: AI-powered educational platforms can personalize learning experiences, adapting content and pacing to individual students' needs.

   - Intelligent Tutoring: AI systems can provide personalized guidance and feedback to students, assisting them in their learning journeys.

   - Automated Grading: AI algorithms can automate the grading of assignments and assessments, saving time for educators.

These are just a few examples of how AI is being applied in real-world scenarios. AI's potential spans across numerous industries, revolutionizing processes, enhancing decision-making, and enabling new capabilities. As technology continues to advance, we can expect even more innovative applications of AI in the future.

 

v  The Benefits and Challenges of AI

 

Here are some advantages of AI in various industries:

 

1. Healthcare:

   - Enhanced Diagnosis: AI algorithms can analyze vast amounts of medical data, including images, patient records, and genomic data, leading to more accurate and timely diagnoses.

   - Personalized Treatment: AI can analyze patient data and medical research to develop personalized treatment plans, considering individual factors such as genetics, medical history, and lifestyle.

   - Efficient Healthcare Delivery: AI-powered chatbots and virtual assistants can provide 24/7 support, answer basic medical queries, and help triage patients, reducing the burden on healthcare professionals.

 2. Finance:

   - Improved Fraud Detection: AI algorithms can detect patterns and anomalies in financial transactions in real-time, helping to identify and prevent fraudulent activities more effectively.

   - Enhanced Risk Assessment: AI can analyze vast amounts of financial and market data, enabling more accurate risk assessment and aiding in investment decision-making.

   - Automated Processes: AI can automate various financial processes, such as document processing, customer support, and regulatory compliance, reducing manual effort and increasing efficiency.

 3. Transportation:

   - Safer and Autonomous Vehicles: AI enables self-driving cars and autonomous vehicles, which have the potential to significantly reduce accidents and improve road safety.

   - Traffic Optimization: AI algorithms can analyze traffic patterns, predict congestion, and optimize traffic signals, leading to smoother traffic flow and reduced travel times.

   - Efficient Fleet Management: AI can optimize logistics and route planning, leading to cost savings, reduced fuel consumption, and improved delivery schedules.

 4. Manufacturing:

   - Improved Efficiency and Productivity: AI-powered automation and robotics can streamline manufacturing processes, increasing production efficiency, and reducing errors.

   - Predictive Maintenance: AI algorithms can analyze sensor data from machinery to detect anomalies and predict maintenance needs, minimizing downtime and optimizing maintenance schedules.

   - Quality Control: AI systems can perform automated visual inspections, ensuring product quality and reducing the need for manual inspection efforts.

 5. Retail:

   - Personalized Shopping Experience: AI-powered recommendation systems can analyze customer data and preferences to provide personalized product recommendations, enhancing the shopping experience and increasing customer satisfaction.

   - Inventory Management: AI algorithms can forecast demand, optimize inventory levels, and automate supply chain processes, reducing stockouts and minimizing inventory holding costs.

   - Enhanced Customer Support: AI chatbots and virtual assistants can provide instant and personalized customer support, answering queries, assisting with purchases, and resolving issues.

 These advantages demonstrate how AI is transforming industries by improving efficiency, accuracy, decision-making, and customer experiences. By harnessing the power of AI, organizations can unlock new opportunities, streamline processes, and gain a competitive edge in their respective fields.

v  Potential challenges and ethical considerations (job displacement, bias, privacy concerns, etc.)

Here are some potential challenges and ethical considerations associated with AI:

1. Job Displacement: One of the significant concerns with AI is the potential for job displacement. As AI automation and robotics advance, certain tasks and roles previously performed by humans may become automated, leading to changes in the job market. This can result in job losses and require individuals to adapt their skills to new roles that complement AI technologies.

 2. Bias and Fairness: AI algorithms are trained on large datasets, and if those datasets are biased or contain unfair representations, the AI systems can perpetuate and amplify those biases. This can lead to discriminatory outcomes in areas such as hiring, lending, and criminal justice. It is essential to address bias and ensure fairness throughout the development and deployment of AI systems.

 3. Privacy Concerns: AI relies on vast amounts of data, including personal information, to make informed decisions. This raises concerns about the privacy and security of individuals' data. Safeguarding data and ensuring proper consent, transparency, and control over personal information are crucial in AI applications to maintain privacy rights.

 4. Ethical Decision-Making: AI systems may encounter situations that require ethical decision-making. For instance, autonomous vehicles might face situations where they have to make split-second decisions that may impact human lives. Determining the ethical framework for such decisions and ensuring AI aligns with societal values is a complex challenge.

 5. Transparency and Explainability: AI algorithms, particularly in deep learning, can be highly complex and opaque. Understanding how AI arrives at its decisions or predictions (i.e., explainability) can be difficult. This lack of transparency raises concerns about accountability, trust, and the ability to address biases or errors.

 6. Security Risks: AI systems can become vulnerable to attacks, including adversarial attacks, where malicious actors intentionally manipulate input data to deceive the AI system. Ensuring the security and integrity of AI systems is crucial, especially in critical applications like healthcare, finance, and transportation.

 7. Social Impact and Inequality: The adoption of AI may have uneven effects on different segments of society, potentially exacerbating existing inequalities. Access to AI technologies, biases in training data, and resource distribution can contribute to social disparities if not carefully addressed.

 Addressing these challenges and ethical considerations requires collaboration among researchers, policymakers, industry stakeholders, and the public. Robust regulations, transparency measures, diversity in AI development teams, and ongoing evaluation of AI systems are some of the steps toward responsible and ethical AI deployment. It is important to ensure that AI is developed and utilized in a manner that respects human rights, values fairness, and benefits society as a whole.

v  Balancing AI advancements with human control and responsibility

Balancing AI advancements with human control and responsibility is crucial to ensure the ethical and responsible development and deployment of AI. Here are some key aspects to consider:

 1. Human Oversight: It is essential to maintain human oversight and decision-making in AI systems. While AI can automate processes and make predictions, humans should have the final say in critical decisions. Humans can provide context, ethical judgment, and accountability, ensuring that AI systems align with societal values and legal frameworks.

 2. Transparent and Explainable AI: AI systems should be transparent and explainable to understand how they arrive at decisions or predictions. This enables humans to evaluate the reasoning behind AI outcomes, detect biases or errors, and hold AI systems accountable. Methods for explainability and interpretability in AI algorithms should be developed and employed.

 3. Ethical Frameworks and Regulations: Clear ethical frameworks and regulations are necessary to guide the development and use of AI. These frameworks should address concerns such as fairness, bias, privacy, security, and accountability. They should be developed through collaboration among experts, policymakers, and stakeholders, and should evolve with changing technological landscapes.

 4. Human-AI Collaboration: AI should be seen as a tool to augment human capabilities rather than replace them. Emphasizing human-AI collaboration can leverage the strengths of both humans and machines. Humans can provide critical thinking, creativity, empathy, and contextual understanding, while AI can process vast amounts of data, identify patterns, and assist with complex tasks.

 5. Training Data and Bias Mitigation: Care should be taken to ensure that training data used to develop AI systems is diverse, representative, and free from bias. Data collection processes should be designed to prevent biased or unfair representations. Bias mitigation techniques should be employed during the training and validation stages to minimize discriminatory outcomes.

 6. Continuous Monitoring and Evaluation: AI systems should be continuously monitored and evaluated to assess their performance, impact, and adherence to ethical guidelines. Regular audits, user feedback, and third-party assessments can help identify and address potential issues, ensuring that AI remains aligned with human values and societal needs.

 7. Public Engagement and Education: Engaging the public in discussions about AI and its implications is vital. Public input and diverse perspectives can help shape policies, ethical standards, and guidelines. Educational initiatives can help increase AI literacy and empower individuals to understand, question, and participate in the development and use of AI technologies.

 By actively considering these aspects, we can strike a balance between AI advancements and human control. This balance ensures that AI remains a beneficial tool, serving humanity's best interests while upholding ethical standards, responsibility, and accountability.


Friday 20 January 2023

What is cloud Computing ?

Cloud computing is the delivery of computing services—including servers, storage, databases, networking, software, analytics, and intelligence—over the Internet (“the cloud”) to offer faster innovation, flexible resources, and economies of scale. You typically pay only for cloud services you use, helping lower your operating costs, run your infrastructure more efficiently and scale as your business needs change.

There are three main types of cloud computing services:
  1. Infrastructure as a Service (IaaS): This type of cloud service provides virtualized computing resources over the internet, such as virtual machines, storage, and networking. This allows users to spin up and configure their own servers and other infrastructure on-demand. Examples of IaaS providers include Amazon Web Services (AWS), Microsoft Azure, and Google Cloud Platform (GCP).
  2. Platform as a Service (PaaS): This type of cloud service provides a platform for users to develop, run, and manage web applications without the need to maintain the underlying infrastructure. This includes things like web servers, databases, and programming languages. Examples of PaaS providers include Heroku, AWS Elastic Beanstalk, and Azure App Service.
  3. Software as a Service (SaaS): This type of cloud service provides users with access to software applications over the internet, typically through a web browser. These applications are managed and maintained by a third-party vendor, and users only need to pay for the service they use. Examples of SaaS providers include Salesforce, Google G Suite, and Microsoft Office 365.
Cloud computing allows organizations to access computing resources and services on demand, without the need to invest in and maintain their own infrastructure. This can reduce costs and increase flexibility, scalability, and innovation.
#cloud #cloudcomputing

Sunday 16 February 2014

Hyper V (Visor)

Hyper V is the virtualization technology from Microsoft i.e. available in 64 bit version of windows server 2008. A hyper visor is a thin layer of software that runs on top of the hardware and below the parent operating system .When a hyper visor is installed both the parent and guest have the equal access to to the hardware.

Hyper V features:


  1. It support 64 bit virtual machine.
  2. Each virtual machine can support upto 4 processors. 
  3. In each virtual machine we can assign upto 32 GB of RAM.
  4. We can take the snap short of a running virtual machine so that we can easily revert to any previous state.
  5. Each virtual machine can be easily configure to run with network load balancing .To balance the load across multiple virtual machine.
  6. Virtual machine includes integration components that can greatly improve performance and helps to improve integration of virtual machine with a physical machine.
Hyper V Installation Pre-requisites:

  1. CPU must support 64 bit processor(Intel VT or AMD-V).
  2. Enable virtuallization  support from BIOS.
  3. Operating System: Windows Server 2008 bit edition of standard ,Enterprise and Data Center.

Saturday 1 February 2014

Power Supply Fan does not Work or Emits a lot of Sounds

The power supply fan is not working when the system is switched on or makes a lot of noise. The problem occurs if the power supply fan is not functional or if lot of dust has accumulated on the fan motor.

To troubleshoot this problem:

  1. Shutdown the system,remove the system case cover and clean the dirt or dust from the fan and power supply unit with a vacuum cleaner or with compressed air.
  2. Check the power supply fan and replace it if it has any defects

Friday 31 January 2014

Mounting the Hard Disk Drivers

Hard disk is one of the important devices in the PC which is used for data storage.You can install more than one hard disk as per your requirements.For mounting the Hard disk we have to taken the following steps-
  • Check if the system supports the hard disk capacity.
  • Check the type of the hard disk that you can install e.g. SATA or IDE.
  • Check the instructions and the settings specified on the lable affixed on of the hard disk.
  • In case of IDE the hard disk may be pre-configured as Master as per the factory settings.Let this setting be as it is if you are installing only one hard disk on the system.
  • Before installing the hard disk drive,write down the serial number or product details or information.so if you ever need to contact the vendor, you must provide this information about hard drive prior to assistance.
  • Before placing the hard disk check the power cable form SMPS should reach to the drive
PRECAUTIONS:
  1. Do not drop the hard disk.
  2. Keep all the magnetic materials away from the hard disk drives.
  3. Check if the jumpers are set properly, as shown on the top of the disk.
  4. Do not touch the circuit board and always hold it from sideways.
  5. Keep the drives on the table keeping logic board facing upwards.
  6. Fix it in the bay and ensure that it is not getting ground.
  7. If you are installing two hard disk drives always place an insulation material between these two drives.

Wednesday 11 December 2013

Upgrading The BIOS

The BIOS is needed if the computer is not capable of using all the features of new software or hardware.Updating the BIOS adds additional functions and can also fix all the errors and bugs. You can download the BIOS update from motherboard manufacturer's website or contact the motherboard manufacturer by phone.
There are two different ways available  for upgrading a motherboard BIOS:
  • Replacing Physical BIOS Chip- Enables the  user to upgrade motherboard BIOS with the new systems. In the new system the original BIOS chip is removed and a new BIOS chip is inserted.The new BIOS should match the old systems motherboard and chipset,using its existing CPU .It provides enhanced features specified by the upgrade BIOS manufacturer. However , if the BIOS are of DIP package , which is not permanently soldered on the motherboard, the BIOS chip can be removed and you can install a newer version of the chip on the motherboard. Also, you can get the updated BIOS by removing the old motherboard and installing a new motherboard in your system.You need to customize the BIOS to match the old motherboard system and chipset.You can use the existing CPU and provide the enhanced features specified by the upgrade BIOS manufacturer.
  • Performing a Flash Update- Enables the user to upgrade motherboard BIOS with new systems. In the new system the update software is downloaded and installed onto a disk for the systems which has flash-upgradeable BIOS.This disk is then used to boot the computer. The new BIOS code is then copied to the BIOS chip.This process of copying takes about 3 to 5 minutes. You can download the BIOS from the companies website. Some motherboards have a flash recovery jumper that is used to restore the system if BIOS upgrade using the BIOS upgrade using the BIOS upgrade software fails.You can also update your BIOS if your system has an Electronically Erasable Programmable Read Only Memory (EEPROM) or flash ROM for the BIOS.


Thank You


Wednesday 20 November 2013

Types Of RAM

RAM is the main memory of the computer. It holds the data unit the system is turned off. Once the system is switched off, the data is lost.As a result, it is known as the temporary data storage area. There are two types of RAM, Static RAM and Dynamic RAM. 

Static Random Access Memory(SRAM)
SRAM is the type of semiconductor memory. It stores the data as long as the power is supplied to the system . Once the power is turned off or is lost temporarily,data stored in SRAM is lost. SRAM uses six transistors for each memory cell. Due to more number of transistors present in the cell, the cell do not refresh frequently.Hence,the data is stored for longer period. Refreshing a cell means re-writing data in a cell.
SRAM is faster in accessing data. The data accessing speed of SRAM makes it behave like a cache memory .SRAM is expensive as compared to DRAM . Example of SRAM is all types of Cache Memory.

Dynamic Random Access Memory(DRAM)
The lifetime of data in RAM is very short.It is approximately for four milliseconds.The data in DRAM are stored in memory cells. Each memory cell contains a pair of a transistor and a capacitor.Each memory cell contains a pair of a transistor and a capacitor.Each memory cell is referred as a bit of data, the smallest amount of information that the system can work with. The memory cells of DRAM are refreshed by DRAM controller after every few milliseconds to retain the data in the memory.
The cells in DRAM are arranged in rows and columns .Each  cell has a row and a column reference number. DRAM accesses the data using the cell reference number. DRAM is less expensive than SRAM

Tuesday 19 November 2013

Upgrading The Memory

The memory of the system must be upgraded to increase the speed of the system.The memory is upgraded either by changing the previous RAM or by adding one more RAM with the previous RAM. The installation of a new RAM depends on the number of the free memory slots available on the motherboard.
Before installing a new RAM,check the type of RAM for mounting on the motherboard. The new RAM should match with the configuration of the previous RAM and should supported by motherboard and processor.
To upgrade the memory of the system we have to take following steps:
  • Shutdown the computer and disconnect the power cable from SMPS and all the peripheral devices attached to it.
  • Remove the system case.
  • Wear an anti-static wristband or any other static control device before touching any of the computer components.
  • Hold the RAM module by its edges.Do not touch the chips and connectors of the RAM module.
  • Hold the RAM module perpendicular to the memory socket.
  • Check the notches of the RAM module before placing it on the memory socket.
  • Put a slight pressure while inserting the RAM module on the memory socket.
  • Put the case back to the computer.
  • Connect all the peripheral devices to the computer.
  • Switch on the computer and check the current amount of the RAM.


Monday 18 November 2013

Troubleshooting of Motherboards

If your system Crashes repeatedly,it is possibly due to motherboard failure. However , actual motherboard failure is very rare. It is possible that some other problems like a loose connection, power failure or overheating may cause system failure.
We have to take the following steps :
  • Turn off the system and remove the power cord from the power supply.
  • Check connections on the Motherboard .
  • Restore the BIOS settings to default setting .
  • Ensure that the motherboard is not touching the system case.
Precautions:
  • Wear an anti static wristband.
  • Cleaner 


Thanking You

COMS battery checking

Actually CMOS is not a battery ,it is a technology which is used to construct Integrated Circuit. CMOS stands for Complementary Metal Oxide Semiconductor. This technology is basically used in microprocessor, micro-controller,RAM ,different logic circuit.
To check the CMOS battery we have to take following steps:

  1. Remove the CMOS battery from the motherboard.
  2. Set the multimeter in DC voltage mode
  3. Put the red probe on +ve side (mentioned on the CMOS battery) and black probe on opposite side of the CMOS battery.
  4. If the output voltage shown is grater than 2.5 volts on  multimeter then it is OK otherwise replace the battery.


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Starting a PC for the First Time

When we start the PC,the Basic Input Output System(BIOS) runs a test to check if all the peripheral devices ,memory and hardware of the PC will are working properly.This test is called the Power on Self Test (POST). The PC will boot only if the results of the test are positive.POST is performed before the PC actually boots the operating system.
If any the hardware components of the PC are not in proper condition, the PC will generate beeps.In some cases,if the problem is serious,the PC will not boot at all. The POST happens before most of the components of the PC start.
The following are the functions performed by POST:
  • Checking the power supply
  • Checking the motherboard
  • Comparing the system configuration with the PC configuration program to find any changes made
  • Checking the memory devices and drives
  • Checking the System memory
  • Starts the display and audio devices
The error that causes the system to stop booting are of two types-Non-Fatal and fatal. In case of non-fatal errors like problems in the extended memory,an error message usually appears on the screen.They allow the computer to continue the boot process. In-case of fatal errors like problems in the processor,the boot process stops immediately and the user gets a series of audible beeps. In-case there are no errors in the system configuration or devices,a single beep follows the POST . Then the booting process of the PC starts and the operating system is loaded.

Thank You

All the User account (including Administrator) are disable

First you have to enable administrator account. To do that the several steps have to be taken-
  1. Restart your System and hit several time F8 key.
  2. Chose "Safe mode with command prompt."
  3. In command prompt  type 
          "net user administrator /active:yes"

    4. Protect your administrator with password.

Create System Image and System Repair Disc

  • Run this task by Administrative Rights
Hardware/Software Requirements:
  • External Hard disk/ Blank DVD Disk
To Create System Image and System Repair Disc
  1. Click Start→Control Panel→System and Security→Backup and Restore
  2. Click on Create a system image 
          select your option among the three options
          a. On a hard disk
          b. On one or more DVDs
          c. On a network location   
     3. Select the disk where you want to save the backup and click Next button.
     4. Click Next Button.
     5. Click on Start backup button. Create a system Image screen appear.
     6. Create a system repair disc screen appear.
     7. Click on Yes button and Insert a blank writable DVD in DVD-ROM Drive.
     8. Click Create Disc.
     9. The creating a System Repair  Disk dialog box appears.
    10. Using the system repair disc screen appears.
    11. Click Close.

OSI Layer and their functions

   LAYERS                     FUNCTIONS                        DATA FORMAT             DEVICE USED

7 Application           Creating a data at user interface             File                             Computer

6 Presentation          Compressing ,Encryption                       File                            Computer

5 Session               i. Establish connection between
                                  transmitter and receiver .                       N.A                            Computer
                             ii. Maintaining, controlling, terminating
                                  the communication

4 Transport            Identifying the relevant process or we      Segment                  Computer
                              can say: "Process-to-process "delivery.

3 Network             Identify relevant host or we can say         Data gram                 Router
                               "host-to-host" delivery .

2 Data link            Identifying relevant hardware.                   Frame                       Switch

1 Physical             Use for  establishing electrical link            Bits( 0 & 1 )      Hub, Cable, wires
                            between the each pair of devices.
                 

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