From: http://sitestree.com/?p=369
Categories:Web Development, Root, By Sayed Ahmed
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Post Data:2013-09-07 20:52:32

From: http://sitestree.com/?p=334
Categories:Web Development, Root, By Sayed Ahmed
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Post Data:2013-08-20 23:14:54

The idea is very simple, the signals are in the air. You need some electrical/electronics components to receive the signal. Adjust/tune the signal to find the best radio signal, and then pass through an amplifier. Eventually you need to pass the signal to a headphone to be able to listen to it.

Technical:
The idea is, you use transistors to detected FM modulated radio signals. Then you use coils and capacitors to tune to the strongest radio signal available. then you pass this signal through an amplifier. Eventually, the signal can be passed to a headphone for listening to the music.

You can get a very basic FM radio receiver circuit at:
http://www.electroschematics.com/5150/tiny-fm-radio/

This is one of simplest and smallest FM radio receiver that can receive the FM stations available locally.

For transistors you can use: BF 494 [two of them in the circuit]
Coil: L 18 SWG, 4 turns air coil
Capacitors: 22 pF, 0.22 pF for tuning, also another 0.1 microF, 220microF
Amplifier: LM386

If you need details on the radio signal stuff, you can read the page
How FM/AM radio works: http://stereos.about.com/od/stereoscience/a/AMFMRadio.htm

a comment from a user about the circuit:
”
This is a nice little circuit! It is quite tricky to get it to work, but it is worth it. I attached it to my buildings TV antenna and use a big variable capacitor (~400pF) with a ~25 turns coil to receive international radio stations from around the world! My suggestions to anyone who wants to try this: replace R1 with a pot to fine tune (I use a 10k pot in series with a 15k fixed resistor). And use pins 1 and 8 of the LM386 to raise the gain when receiving weaker stations.

” From: http://sitestree.com/?p=305
Categories:Web Development, Root, By Sayed Ahmed
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Post Data:2013-05-31 18:17:47

Before 19th century no one systematically studied the effectiveness o f the different approaches of management
Business Analysis – is a very recent profession. Due to the radical change in information management and communication businesses needed a new way of analysis – hence, the profession came into play
The profession came into existence during the information technology boom in 1980 – 1990
When businesses created a new profession to serve the purpose that a System Analyst does in IT – the profession became the business analyst
Though, nothing can guarantee success, understanding the core concepts of the Business Analysis area will help you to work more effectively as a business analyst
Six knowledge areas of Business Analysis:
Enterprise Analysis
Requirements Planning and Management
Requirements Elicitation
Requirements Analysis and Documentation
Requirements Communication
Solution Assessment and Validation
Responsibilities of a Business Analyst
Identify Business Problems and Opportunities
Eliciting, Analyzing, Communicating, and validating requirements for changes to business processes
Recommending solutions to help businesses achieve their goals
The role of the project managers and business analysts may seem similar. Really, there are some overlapping areas such as, identifying goals and requirements, risk analysis, and finding strategies for project success. However, the project manager is responsible for the timely completion of the project within the budget. The business analyst ensures that the project is completed correctly with the defined requirements. From: http://sitestree.com/?p=285
Categories:Web Development, Root, By Sayed Ahmed
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Post Data:2013-04-26 23:41:12

File System Access and PHP Security

Allowing your users to upload files opens some security holes. Users can upload malicious files and make your site affected by Malware. How risky is this depends on how you implemented the feature, and the privileges that you have provided. One option can be check if the associated feature is really important or it is a feature just for the sake of a feature.

One option to prevent or minimize attack is: always specifically mention where the uploaded contents will go. Specify the upload folder specifically. When users upload files, check the name of the files as well. Are they trying to access a different location using relative parameters such as ../? Check the type of files they are trying to upload? is it an exe file? what about the size of the file? is the user trying to upload repeatedly?
is he a real human being? check the feature with Captcha.

Do not use relative paths in your code; also do not specify a file upload location using relative paths. Do not assume that only the folder under which the website resides is the only place to keep uploaded files. You can define another location from your code that is usually inaccessible from the users. Your root website folder is public and is not the best place to keep uploaded files.

Also, when you are opening a file do not use relative paths; try to know the exact location and filename; and work with the specific location and file name.

PHP by default allows remote file access which is a really bad idea. Unless you have a good reason to allow remote file access, turn it off. you can turn it off from php.ini file. To do that just disable allow_url_fopen

However, if you really need to allow using remote files, do not directly open/execute it. But do it in two steps, first retrieve the data and then process the data in the 2nd step. You can use FTP functionality to retrieve/upload first and then you can process it. From: http://sitestree.com/?p=217
Categories:Web Development, Root, By Sayed Ahmed
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Post Data:2013-01-27 21:28:17

http://www2.gre.ac.uk/study/courses/pg/com/dmdm
http://oregonstate.edu/is/training/admin-systems-training/sis-training/dw
https://www.villanovau.com/lp/business-intelligence/career/cert-mst_gainknowledge_t04_1110/?mcguid=7efad90f-381a-4f60-8908-20aaf505e364&mcid=24098&WT.srch=1&mkwid=sxXUgffxJ_dc&pcrid=27800095324&pmt=b&pkw=data%20warehouse%20certification&gclid=CKKGxaTCtrwCFe1cMgodK0cAGA
https://wiki.engr.illinois.edu/display/cs412/2.+Course+Syllabus+and+Schedule From: http://sitestree.com/?p=738
Categories:Web Development, Root, By Sayed Ahmed, Data Warehouse – 001, Data Warehouse, Data Warehouse Misc
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Post Data:2014-02-06 03:17:46

Some Random Notes on Hadoop…

Why Hadoop? …randomly came across again….so, Just some random stuff. I may try to relate my exposure to it (or something), even that remotely relates to Hadoop

What is Hadoop?

Apache Hadoop is an open-source software framework for storage and large scale processing of data-sets on clusters of commodity hardware. Hadoop is an Apache top-level project being built and used by a global community of contributors and users.^[2] It is licensed under the Apache License 2.0. (Wikipedia)

“Hadoop is one way of using an enormous cluster of computers to store an enormous amount of data and then to operate on that data in parallel.” Reference : http://escience.washington.edu

Hadoop Salary in San Jose, California, USA

http://www.indeed.com/salary?q1=hadoop&l1=san+jose+ca

—

Hadoop Salary in Toronto, Ontario, Canada
http://www.indeed.com/salary?q1=hadoop&l1=toronto%2C+ontario%2C+canada

Hadoop and Parallel Computing and Distributed Database:

http://escience.washington.edu/get-help-now/what-hadoop

A course on Parallel Computing (Yes, I took it): http://www.geocities.ws/sayedbuet94/parallel/classnotes/

Introduction to distributed DBMS: https://cs.uwaterloo.ca/…/cs856/F02/lecture-1-ho.pdf

Book On Distributed DBMS: Yes it’s theory: For Jobs, you need to study practical stuff. http://www.stanford.edu/class/cs347/reading/textbook.pdf

Yes, I took a Distributed DBMS, theory course.

Application of Hadoop

Keith Wiley: Astronomical Image Processing with Hadoop http://escience.washington.edu/…

A Presentation document by me on Database System Architectures

An Apache Hadoop Tutorial: MapReduce with Apache Hadoop

Hadoop Applicatioon: Data-Intensive Text Processing with MapReduce

I have some research publications on Parallel Computing as can be seen at: http://sayed.justetc.net/publications.php

Implemented in MPI and OpenMP. For sure the code were run in Parallel Computers [Clusters of Computers]

I did a part time Research Assistant work on Running Parallel Programs to find some code, and then report the finding after running for a while [do not remember it was few days or a week] From: http://sitestree.com/?p=524
Categories:Web Development, Root, By Sayed Ahmed, Data Warehouse Misc
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Post Data:2013-11-08 23:39:53

HTML 5 at a Glance
[ More HTML & CSS ][ More HTML & CSS ]

By Sayed Ahmed on 2012-10-03

HTML 5 at a Glance

HTML5 Server-Sent Events

Servers can send upda tes automatically even if the client did not ask for it. For example, Facebook updates and Twitter Updates

The idea is you have to use the EventSource object to point to the remote script sending updates. Then you have to act upon the events onopen, onmessage, and onerror [the client script has to perform action on these events]. The onmessage event is the most useful. onmessage event occurs when the server sends meaages [and then you need to process the message as sent by the server]

How to check if the browser supports it or not

SSE is supported by all major browsers except Internet Explorer.

if(typeof(EventSource)!=="undefined") { // Yes! } else { // Sorry! No }

Example onmessage event

var script_source=new EventSource(“source.php”);
source.onmessage=function(event)
{
document.getElementById(“elementToChange”).innerHTML+=event.data + ”
“;
};

Server Side Code Example

HTML 5 Web Worker

A Web Worker is a JavaScript Code running in the background without interfering (delaying) user interactions. Usually written in separate JavaScript files. However, webworkers can send messages to the frontend on onmessage event. Web Worker JS does not have access to the Document, Window and Parent objects.

Web Workers are supported by all major browsers except IE

Example use: You can keep options in buttons or texts to start and stop the web worker. On click on the start, the web worker defined in a separate JS file starts executing.

wrker = new Worker(“js_file_for_processing.js”); //how you start the background work.

On the stop button click, you can just call the terminate method (wrker.terminate). You can also check if the browser supports web worker or not using the following code if(typeof(Worker)!==”undefined”) { // Yes! } else { // Sorry! }

<script>
var wrker;

function start_web_Worker()
{
if(typeof(Worker)!==”undefined”)
{
if(typeof(wrker)==”undefined”)
{
wrker=new Worker(“wrker_js.js”);
}
w.onmessage = function (event) {
document.getElementById(“sum”).innerHTML=event.data;
};
}
else
{
document.getElementById(“sum”).innerHTML=”browser does not support web worker”;
}
}

function stop_web_Worker()
{
wrker.terminate();
}
</script>

HTML5 Application Cache

Supported by all major browsers except IE

In HTML 5, you can specify whether a page will be cached in the client side or not using HTML itself. Caching makes the application faster, and offers offline browsing of the website. You can use manifest attribute for the HTML tag to specify whether a page will be cached or not or you can mention in a manifest file what pages need to be cached and what pages are not cacheable.

< html manifest=”manifest_file.appcache” >

Manifest file example

CACHE MANIFEST
#will be cached
/x.css
/y.gif
/z.js

NETWORK:
#will never be cached
login.asp

FALLBACK:
#if a file cannot be found what page should be displayed
/html/forms/name.php /error.php

HTML5 Web Storage

supported by Internet Explorer 8+, Firefox, Opera, Chrome, and Safari.

This is cookie like storage but more secure and faster. Storage is the object used for the purpose. Large amounts of data can be stored without affecting the performance. There are two types of storage localStorage, and sessionStorage. localStorage has no expirartion date but sessionStorage is only for the current seession. And for sure, a webpage can only access data stored by itself. The data are stored as key value pairs

HTML5 Form Attributes

autocomplete, novalidate are the two new attributes for the form tag. autocomplete indicates if the form elements will be turned on or off for autocomplete. novalidate indicates when the form will be submitted, no validation will be performed on the data.

HTML 5 introduces some new attributes for the input element such as autocomplete, autofocus, form, formaction, formenctype, formmethod, formnovalidate, formtarget, height and width, list, min and max, multiple, pattern (regexp), paceholder, required, step. Will talk on them in a later article

HTML5 New Form Elements

datalist: pre defined list of data for an input element
keygen: generates public key and private key
output: used to keep output data

Example

<form action=”” method=”get”>
<input list=”browsers”><datalist id=”browsers”>
<option value=”Internet Explorer”>
<option value=”Firefox”>
<option value=”Chrome”>
<option value=”Opera”>
<option value=”Safari”>
</datalist>
<keygen name=”security”>
<output name=”x” for=”a b”></output>
</form>

HTML 5 New Input Types

New input types include: color, date, datetime, datetime-local, email, month, number, range, search, tel, time, url, week

Example

<input type=”color” name=”…”>
<input type=”date” name=”…”>
<input type=”datetime” name=”…”>
<input type=”datetime-local” name=”…”>
<input type=”email” name=”…”>
<input type=”month” name=”…”>
<input type=”number” name=”…” min=”1″ max=”5″>
<input type=”range” name=”…” min=”1″ max=”10″>
<input type=”search” name=”…”>
<input type=”tel” name=”…”>
<input type=”time” name=”…”>
<input type=”url” name=”…”>
<input type=”week” name=”…”>

HTML5 Audio

Supported by: Internet Explorer 9, Firefox, Opera, Chrome, and Safari

No need to use Flash to play sound, HTML5 provides ways to play audio files

Example

<audio controls=”controls”>
<source src=”xyz.ogg” type=”audio/ogg”>
<source src=”xyz.mp3″ type=”audio/mpeg”>
</audio>

You can use multiple sources, the browser will go with the first recognized format

HTML5 Video

Supported by: Internet Explorer 9, Firefox, Opera, Chrome, and Safari

<video width=”320″ height=”240″ controls=”controls”>
<source src=”xyz.mp4″ type=”video/mp4″>
<source src=”xyz.ogg” type=”video/ogg”>
</video>

HTML5 Geolocation

navigator.geolocation.getCurrentPosition can be used to find user’s current position

HTML5 Drag and Drop

Any element is draggable

The element you want to drag needs to use the attribute draggable=”true”; You need to use ondragstart and setData() to specify what should happen on drag event. ondragover mentions where the dragged data can be dropped.

HTML5 Inline SVG: Supporting Vector Graphics

In HTML5, you can use SVG tag to include vector graphics. SVG defines graphics in xml format. Vector Graphics are independent of resolution, can have events, can be manipulated without being redrawn

HTML5 Canvas

Defines an area in the web-page where drawings can be done using some scripts such as JavaScript.

<canvas id=”myCanvas” width=”200″ height=”100″></canvas>

Canvas Example

<script type=”text/javascript”>
var c=document.getElementById(“canvas_id”);
var ctx=c.getContext(“2d”);
ctx.fillStyle=”#FFFF00″;
ctx.fillRect(0,0,200,100);
</script>

New Elements in HTML5

article, aside, bdi, command, details, summary, figure, figcaption, footer, header, hgroup, mark, meter, nav, progress, ruby, rt, section, time, wbr From: http://sitestree.com/?p=342
Categories:Web Development, Root, By Sayed Ahmed, Introduction to HTML 5
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Post Data:2013-08-23 18:46:33