Cost Benefit Analysis

Cost–benefit analysis (CBA), sometimes called benefit–cost analysis (BCA), is a systematic approach to estimating the strengths and weaknesses of alternatives that satisfy transactions, activities or functional requirements for a business. It is a technique that is used to determine options that provide the best approach for the adoption and practice in terms of benefits in labor, time and cost savings etc. The CBA is also defined as a systematic process for calculating and comparing benefits and costs of a project, decision or government policy (hereafter, "project").

• Determine on-going staffing costs - an analysis of the operating costs (actual versus proposed). This is based on the rough design of the planned system and its anticipated impact on the company.
• Estimated savings and expenses by user department areas (e.g., Manufacturing, Marketing, etc.). This describes the on-going costs associated with the system, as well as the anticipated savings.
• Itemized benefits - both tangible and intangible. In the systems world, the biggest benefits are typically intangible in nature. A benefit is typically written beginning with a transitive verb, such as improve, maximize, minimize, etc. Substantiate your claim; do not simply say Improved cash flow; instead, say something like, Improved cash flow through tighter control over inventory and faster response from Production.
• Break Even point - the calculated point in time where cost savings match accumulated development expenses. It is normally calculated as: Break Even Point = Investment ÷ Average Annual Savings For example, where the project Investment was $49,215 and the Average Annual Savings was $22,861, the Break Even Point is 2.15 years (26 months)
• Calculate Return On Investment (ROI) - the ratio of projected cost savings versus amount invested. It is typically calculated as: ROI = (Average Annual Savings ÷ Investment) X 100 Using the figures from above, the ROI is 46.4%

Explain RAD and Waterfall model ?

Defination RAD :

RAD model is Rapid Application Development model. It is a type of incremental model. In RAD model the components or functions are developed in parallel as if they were mini projects. The developments are time boxed, delivered and then assembled into a working prototype. This can quickly give the customer something to see and use and to provide feedback regarding the delivery and their requirements.

Diagram of RAD-Model:

The phases in the rapid application development (RAD) model are:

Business modeling: The information flow is identified between various business functions.

Data modeling: Information gathered from business modeling is used to define data objects that are needed for the business.

Process modeling: Data objects defined in data modeling are converted to achieve the business information flow to achieve some specific business objective. Description are identified and created for CRUD of data objects.

Application generation: Automated tools are used to convert process models into code and the actual system.

Testing and turnover: Test new components and all the interfaces.

Advantages of the RAD model:

• Reduced development time.
• Increases reusability of components
• Quick initial reviews occur
• Encourages customer feedback
• Integration from very beginning solves a lot of integration issues.

Disadvantages of RAD model:

• Depends on strong team and individual performances for identifying business requirements.
• Only system that can be modularized can be built using RAD
• Requires highly skilled developers/designers.
• High dependency on modeling skills
• Inapplicable to cheaper projects as cost of modeling and automated codegeneration is very high.

Defination Waterfall Model:

The Waterfall Model was first Process Model to be introduced. It is also referred to as a linear-sequential life cycle model.  It is very simple to understand and use.  In a waterfall model, each phase must be completed fully before the next phase can begin. This type of model is basically used for the for the project which is small and there are no uncertain requirements.At the end of each phase, a review takes place to determine if the project is on the right path and whether or not to continue or discard the project. In this model the testing starts only after the development is complete. In waterfall model phases do not overlap.

Diagram of Waterfall-model: 

Advantages of waterfall model:

• This model is simple and easy to understand and use.
• It is easy to manage due to the rigidity of the model – each phase has specific deliverables and a review process.
• In this model phases are processed and completed one at a time. Phases do not overlap.
• Waterfall model works well for smaller projects where requirements are very well understood.

 Disadvantages of waterfall model:

• Once an application is in the testing stage, it is very difficult to go back and change something that was not well-thought out in the concept stage.
• No working software is produced until late during the life cycle.
• High amounts of risk and uncertainty.
• Not a good model for complex and object-oriented projects.
• Poor model for long and ongoing projects.
• Not suitable for the projects where requirements are at a moderate to high risk of changing.

What Is Fact Finding And Its Methods ?

Defination : 

Fact finding is process of collection of data and information based on techniques which contain sampling of existing documents, research, observation, questionnaires, interviews, prototyping and joint requirements planning. System analyst uses suitable fact-finding techniques to develop and implement the current existing system. Collecting required facts are very important to apply tools in System Development Life Cycle because tools cannot be used efficiently and effectively without proper extracting from facts. Fact-finding techniques are used in the early stage of System Development Life Cycle including system analysis phase, design and post implementation review. Facts included in any information system can be tested based on three steps: data- facts used to create useful information, process- functions to perform the objectives and interface- designs to interact with users.

There are seven common fact-finding techniques :

Sampling of existing documentation, forms and databases

Research and Site visits

Observation of the work environment

Questionnaires

Interviews

Prototyping

Joint requirements planning

Interview
This method is used to collect the information from groups or individuals. Analyst selects the people who are related with the system for the interview. In this method the analyst sits face to face with the people and records their responses. The interviewer must plan in advance the type of questions he/ she is going to ask and should be ready to answer any type of question. He should also choose a suitable place and time which will be comfortable for the respondent.

The information collected is quite accurate and reliable as the interviewer can clear and cross check the doubts there itself. This method also helps gap the areas of misunderstandings and help to discuss about the future problems. Structured and unstructured are the two sub categories of Interview. Structured interview is more formal interview where fixed questions are asked and specific information is collected whereas unstructured interview is more or less like a casual conversation where in-depth areas topics are covered and other information apart from the topic may also be obtained.


Questionnaire
It is the technique used to extract information from number of people. This method can be adopted and used only by an skillful analyst. The Questionnaire consists of series of questions framed together in logical manner. The questions are simple, clear and to the point. This method is very useful for attaining information from people who are concerned with the usage of the system and who are living in different countries. The questionnaire can be mailed or send to people by post. This is the cheapest source of fact finding.


Record View
The information related to the system is published in the sources like newspapers, magazines, journals, documents etc. This record review helps the analyst to get valuable information about the system and the organization.

Observation
Unlike the other fact finding techniques, in this method the analyst himself visits the organization and observes and understand the flow of documents, working of the existing system, the users of the system etc. For this method to be adopted it takes an analyst to perform this job as he knows which points should be noticed and highlighted. In analyst may observe the unwanted things as well and simply cause delay in the development of the new system.

How to Install Laravel 4 with an Apache Web Server on Ubuntu 14.04

Laravel is a open source PHP framework for web developers. It aims to provide an easy, elegant way for developers to get a fully functional web application running quickly.

Here we will dissuss how setup laravel step by step from scratch.

Preparing the server / environment

sudo apt-get update
sudo apt-get upgrade

Preparation of installing PHP 5
Installing Apache, PHP and MySQL

sudo apt-get install apache2
sudo apt-get install php5
sudo apt-get install mysql-server
sudo apt-get install php5-mysql

The installation process is self-explaining. You can prove the installed versions of PHP and Apache with:

php -v
apache2 -v

Installing necessary PHP extensions

sudo apt-get install unzip
sudo apt-get install curl
sudo apt-get install openssl
sudo apt-get install php5-mcrypt

Install Composer (systemwide)

curl -sS https://getcomposer.org/installer | php
sudo mv composer.phar /usr/local/bin/composer
Activate mod_rewrite
sudo a2enmod rewrite
sudo service apache2 restart

Install Laravel 4

cd /var/www/laraveldev
wget https://github.com/laravel/laravel/archive/master.zip
unzip master.zip && cd laravel-master/ && mv * ../ && cd ..
rm -r laravel-master && rm master.zip

Make the storage folder writeable and restart the server:

sudo chmod -R 777 app/storage
sudo service apache2 restart

First run of Laravel 4
Now edit app/routes.php and add a new route:

Route::get(‘/mytest’, function() {
    return “Oh yeah, this really works !”;
});

Now you navigate to your the browser.

http://your-domain-or-ip/mytest

Drupal caching using cache_get and cache_set

Drupal functions cache_get and cache_set are basically used for static caching temporarly and permanently in the cache table of the drupal database.

Using cache_set function is fairly simple below is a syntax of how you can implement this.

cache_set(key, value, 'cache', CACHE_TEMPORARY); or cache_set(key, value, 'cache', CACHE_PERMANENT); 

cache_set takes four parameters first the key parameter, this parameter is unique for the system and is used to differentiate between other records in the table also this key is used to retrive data from the database the second parameter is the value that is the data to be stored in the key.

Now the third parameter is the table name that is table to store the data in and the fourth parameter is the cache type that is temporary or permanent, if temporary it will flush the cache when the cron runs and if permanent cache type is selected the cache will never expire.

cache_get function is used to retrive the data from the cache table based on the key in the table. Below is the syntax of how you can implement this.

cache_get(key);

The cache_get function when invoked by a key returns an object which contains the cache id as cid the value as the data variable and the expire that is the time it will expire. If expire is set to zero the cache will never expire. Below is a full syntax of how this is implemented.

  $tempdata =  cache_get('cachekey');
  if(isset($tempdata->data)) {
    return $tempdata->data;
  } else {
    $value = "Test Cache Value";
    cache_set('cachekey', $value, 'cache', CACHE_TEMPORARY);
    return $value;
  }