My Tech Zone

WolfarmAlpha

2009-06-29T09:28:00.000-07:00

A month back I had come across one of the best sites that I had ever seen. It not fancy but amount of factual data that this search engine showed me. Yes! It is WolfarmAlpha.

(www.wolfarmalpha.com) This site has been developed by Wolfarm research using their product called Mathematica.

For example I gave my DOB and it gave me how long I am living in days, weeks and even hours. You can even compare the financial statements of any two companies by entering their stock market symbols. You can give a mathematics expression and it solves it for you. I believe that this engine has the potential to be the next big search revolution because it just not searches but also thinks for you.

I am planning to study this site and check how it works. I will be back with more info on this soon.

Nokia 5320

2009-06-28T02:39:00.000-07:00

Couple of months back I had bought a cell phone for my wife. She had drpped her IPod in the washing machine and so the primary reason was to find a cell phone that would also work as a good music player. After considerable research I thought Nokia 5320 would be the best fit. After using the phone for a few months now I think its time to review it.
For persons who are looking for a similar requirement here is what I experienced. It’s a slim bar model phone. Nokia 5320 has 16M colours and has a display resolution of 24 CM x 32 CM. It has an Inbuild memory of 140 MB and good thing is that It has an expandable memory of 8 GB.
It has Bluetooth,USB connector and GPRS but if it had WiFi I would have connected to my wireless modem and downloaded songs /browsed internet without having to connect using my USB or GPRS. It has a good voice recorder but its 2.0 mega pixcel camera is not impressive. However for a music phone I should not be expecting the camera to be anything better. Another impressive feature that attracted me was it was 3G enabled , even though in India I would not be using it now but sure to use it in near future.
Just wanted readers to know that the phone lacks vibration alert but that good for the life of the phone. It has a set of music keys that are accessible in the front. You can control your music even without getting into your phone control. The sound clarity is good. However the headphone was not impressive. It would have been better if they have provided a better headphone. The FM radio feature was also good even when compared to standalone MP3 player from Sony. I think (not sure) the FM antenna of Nokia is doing the trick. Another important feature to note is the standard headphone instead of the custom headphone like the other vendors. I tried even connecting to my PC speakers and it was giving quality sound.
Over all this is a good music phone. Except the camera and headset everything else rocks.

Design Principles for Scalable Applications :

2008-02-07T22:45:00.000-08:00

1) Modules Should be loosely coupled
2) No Component should be significantly more complex than the others.
3) Where ever possible make asynchronous communication.
4) Maintainability should be key
5) Simple Solution Should be the best solution ( No Over Engineering)
5) You should know when to scale out and when to scale up (Scale up : Adding new h/w , Scale out: distributing the work load)2003 web can have only 2 cpus

GUI DESIGN Principles

2008-02-07T22:43:00.000-08:00

Provide a Clear Navigation ( Better if you follow a work flow)
The Most commonly used items should be readily available (Better if you have then on top level menu)
More Intuitive ( use real life metaphor images)
Design For Clarity
Design for consistency
Quicker Response time

Immutability

2007-12-30T09:31:00.000-08:00

Here is a post where I want to share my knowledge on the immutable objects. Immutable refers to items that do not change. I just remember Hendry David's words when he says "Things do not change ; We change." . I believe these works refer s to immutable objects more perfect any other technical definition.

There are several types of immutability , lets talk about them here.

Write-Once immutability :
Constants are compile-time immutable types. These are objects whose values are set during the compile time and latter cannot be changed.
Readonly modifier ensures that the value of the object is set during the runtime and the values never changes.

Dormant Immutability:
Probably I have not coined a nice name for this type of immutability however what I would say is to there could be object which are persisted at some point and when they have to come back to life they are desterilized. In the world of BizTalk this is called hydration and dehydration. In such scenarios the object becomes immutable when it becomes dormant and becomes mutable when its desterilized.

Selective Immutability :
There could be scenarios where an object can be changed only under certain conditions or constraints such objects can be called as selectively immutable.

These are just few kinds which comes to my mind at this point. If someone finds other types feel free to post your comments and take the discussion forward.

Catch you soon …..

Two Phase Commit - 2PC

2007-12-22T23:58:00.000-08:00

Two Phase Commit :
The Two Phase commit (2pc) consist of 2 steps, Prepare and Commit.
Upon receiving a Commit request from the application, the transaction manager begins the Prepare phase of all the enlisted participants by calling the Prepare method on each enlisted resource, in order to obtain each resource's vote on the transaction.

In the second phase of the transaction, if the transaction manager receives successful prepares from all the resource managers (all the resource managers have invoked Prepared at the end of phase 1), it invokes the Commit method for each resource manager. The resource managers can then make the changes durable and complete the commit.

Each resource participating in a transaction is managed by a resource manager and their actions are coordinated by the transaction manager. We should first know what type of resource we are using , either a durable or a volatile resource.[Durable Resource : database] [Volatile Resource : in Memory structure]

Then we have to implement the IEnlistmentNotification

Function Point Analysis.

2007-12-13T20:07:00.000-08:00

I have been trying to learn the art of measuring the complexity of a software using FP analysis.

Finally i am just putting together few points which can help others too.

Functional Point Analysis :

This is a structured technique of classifying the components of the system.
Typically used in measuring the complexity of the system.

Step 1 :

Divide the system in to 5 different classes.
Transactions :
External input (EI)
External Output (EO)
External Inquires (EQ)
Logical Information
External interface (EIF)
Internal Logic (ILF)

Step 2:
After classifying the components into these 5 categories, we have to rank these components as High / low/ medium.
For Transactions , use the Number or Files updated/referenced and DETs as a criteria to rank.
For EIF and ILF use Record Element type and DET as a criteria to rank.

Once you done with the ranking, we can then assign a rating for each of the measures like shown in the 3rd diagram.

Step 3:
Calculate the Unadjusted Function points:

Step 4:
Calculate the Value adjusted Functions point :

This is calculated by giving a ranking for 1 to 5 for each of the following general system characteristics

Data communication
Distributed functions
Performance objectives
Heavily used configuration
Transaction rate
On-line data entry
End-user efficiency
On-line update
Complex processing
Reusability
Installation ease
Operational ease
Multiple sites
Facilitate change
VAF = 0.65 + ( sum of 14 characteristics ) / 100
Step 5
The final Function Point Count is obtained by multiplying the VAF times the Unadjusted Function Point (UAF).
FP = UAF * VAF
Some more advantages :

Can be used to track and manage scope creep.
Can be used irrespective of technology
Can be used to compare tool, language productive

Let me start ...

2007-07-28T22:46:00.000-07:00

Hello Friends ....
I have been a good reader but a bad writter ...This blog is my effort to improve my writting skills and also to share my ideas on technology. Hope I will make this an interesting one for all the readers .....

Hoping to make an impact ...
Yours
- PB