Auto-generate Flow Chart from Java/C++ Codes:

Raptor Flowchart Tutorial For Beginners

Wednesday, August 05, 2009

Mysterious Windows System Slowdown, 98,XP,Vista etc


TheSun:Untying Windows kinks
Some tips to demystify mysterious system slowdowns that drive windows users crazy
Jay Dougherty
COMPUTERS were designed to help you get your work done faster – not to make you wait. Yet, mysterious system slowdowns are a part of life for many Windows users.

Often these slowdowns – ranging from excessive disk thrashing to delays in shutting down or starting up your computer – are easier to troubleshoot than you might imagine.

Here are some tips on how to overcome the problems encountered.


» Windows PC takes a long time to shut down and to restart

Usually when this happens, a device driver is causing Windows to hang for some period of time.

One way to troubleshoot this issue is to temporarily disable most drivers or processes that start up automatically and then re-introduce them one by one until you find the culprit.

You can do this by visiting Windows’ System Configuration utility. Hold down the Windows key and tap the letter R to bring up the Run dialog box, and then type "msconfig", without the quotation marks, in the Run dialogue box’s Open form field. The System Configuration utility appears.

Click the Startup tab in the System Configuration utility. There, you’ll see a list of many of the processes or drivers that start automatically each time you boot up Windows.

Remove the check marks from each of those processes or drivers except for those that you know you need, and then click Apply. Click OK to close the System Configuration utility.

Windows will warn you that you may need to restart your computer to apply the changes. That’s exactly what you want – in order to determine whether the changes worked – so go ahead and restart.

If your PC boots up more quickly, then you know that one of the devices you disabled is the culprit. Go back into msconfig and re-enable processes or devices one by one.

Once you find the offending process, uninstall the programme to which it belongs, and your startup and shutdown issues should be solved.


» After the computer is idle for 15 minutes or so, when attempt is made to retrieve or save a file, the computer hangs for a while before it responds

Chances are good that some power-saving feature is the culprit – most likely a feature that shuts off or spins down the hard drive.

Go into the Windows Control Panel and select Power Options. There, you can explore how soon after a period of inactivity your hard drive is scheduled to spin down. Increase the amount of time before your hard drive spins down, or turn off automatic shutdown of your hard drive altogether.

When your PC’s hard drive is turned off automatically by the Windows power-saving feature, restarting the drive can take some time – sometimes 30 seconds or more, depending upon the drive.


» During the day, the PC shows excessive disk activity, even when you’re not working or saving files

Often this type of problem is caused by some background process. Be especially suspicious of any scheduled activity, such as disk defragmentation, that accesses the hard drive often or intensively.

Vista’s automatic disk defragmenter, for example, has been known to kick in when it should not – such as during the day when you’re actually using your PC.

Visit the disk defragmenter, and make sure that scheduled defragmentation is turned off.

Insufficient system memory can also cause excessive disk activity.

If you notice the activity when you are working with several applications open at once, lack of sufficient memory could be the problem. When Windows runs out of physical memory (RAM), it will use the hard drive as virtual memory, and disk writing – or "paging" – can slow your PC to a crawl.

A third possibility is spyware or malware. Download and install the Malwarebytes (http://www.malwarebytes.org) and have it scan your computer.

This is one of the better freeware anti-malware tools, and if it finds infections on your PC, there’s a good chance that it will be able to remove them.


» After using Microsoft Outlook for almost a year, lately it is taking a long time to start up

First, let’s assume you have not recently installed any add-ons or toolbars in Outlook. If you have, uninstall them.

More typically, Outlook startup slowdowns are caused by a lot of email choking up your system. Specifically, if you have not cleaned out your inbox in some time, you should do so.

Outlook reads the headers in your inbox each time you start the program, assuming you have Outlook setup to go automatically into your inbox.

Move old email messages from the inbox to another folder within Outlook, and you should notice an improvement in startup speed immediately. – dpa


Updated: 03:40PM Mon, 03 Aug 2009

Sliding up to the Nokia E75


TheSun: Sliding up to the E75
N. Shashi Kala


If you aren’t yet an iPhone convert, find the Blackberry charmless and the N series too bulky, the new E75 offers a plausible alternative to your smartphone needs.
The Nokia E series is a business-orientated smartphone with emphasis on connectivity and email. The E series has been around since 2005, and there have been several well-received models, including the E71 and the E90 Communicator.

This new quad-band 3G model’s claim to fame is the side-sliding QWERTY keyboard and screen that lies flat instead of tilting upwards like the E71. It also boasts advances in Nokia’s own email client that makes getting emails on the go absolutely easy.

The slimmed down design belies the myriad features in this 111.8 x 50 x 14.4 mm phone, which weighs 139g – not exactly light, but not a pocket buster either.

The metallic back gives a pleasing feel of sturdiness, and the smooth slide motion does bump up the cool factor. But the front of the unit is not nearly as pretty, and the keypad had this plastic-like texture.

The review unit was red – not the flashy, fire-engine version, but the more understated ruby red.

There’s a 2.4" TFT active matrix display on the front, and a full keyboard on the slider, with an accelerometer sensor for auto-rotate of content.

Design-wise, the front keypad is a bit cramped, especially the system keys beside the D-pad, such as Call, End, Calendar, Home and Backspace. I kept pressing the wrong keys by accident, and it was quite frustrating.

The E75 has a 3.2 megapixel autofocus camera with LED flash, but I was disappointed with the image quality, which was generally poor, even in daylight shooting. Another gripe is the camera button on the side of the phone, which wobbles and doesn’t work very well. I was not impressed.

Considering its price, Nokia really should have done better.

On the plus side, the slide-out keyboard is a smooth operator, and despite the lack of raised keys, you can get used to it rather quickly. The keys are just large enough for typing out notes and quick emails without cramping up your fingers too much. The hotkeys can also be easily customised, and you can choose between active standby, basic or talking theme (yes, this phone talks back to you) to access the menu.

The Nokia E75 runs on Symbian 9.3 OS with the Series60 3rd Edition user interface. It is powered by a 369 MHz CPU, which in theory makes it faster than the E71. Yet, there’s still a bit of a delay when launching applications, but not enough to complain about.

The phone has WiFi capability with a built-in WLAN and it works well. But I really liked is the email client, which is a joy to use.

It’s straightforward and easy to get your email set up – just seconds, actually – by adding in your username and password and you are good to go. Encryption is also included, so really, this is neat.

Nokia has also included a music player in the E75, supporting multiple music formats. It’s easy to transfer files via the Bluetooth support, and the sound quality is good enough for most music lovers.

The phone also offers smooth web-browsing, video player, and the usual business applications.

In a nutshell, the Nokia E75 lives up to its billing as a premier communication device for business people. But a better camera function and front keypad design would really make it a must-buy item.


Updated: 11:48AM Mon, 27 Jul 2009

Tuesday, August 04, 2009

Canon PowerShot A2100 Snap pretty pictures

From The Star:

Tuesday August 4, 2009

Snap pretty pictures

By CHONG JINN XIUNG

Shooting photos can’t get any easier because the Canon PowerShot A2100 IS packs a lot of user-friendly features.

THE PowerShot A2100 IS is a standard point-and-shoot 12.1-megapixel camera that is aimed at amateur and semi-pro photographers.

The A2100 is mostly black with contrasting silver borders — it is not as attractive or elegant as the Ixus series of cameras but it still looks good.

Though the body is made entirely of plastic the build quality feels extremely solid and the camera is comfortable to hold.

Still, it is a shame the A2100 doesn’t have a rubberised handgrip which would give you a firmer hold of the camera.

While there’s nothing remarkable about the design, the camera’s compact size makes it a perfect for lugging it wherever you go.

The A2100 is powered by a pair of AA-size batteries so you can always carry spares on days you are planning to shoot a lot of photos.

One small complaint — the battery compartment also houses the memory card slot. So you’ll have to switch off the camera whenever you want to swap cards.

Modes aplenty

The camera also features a large 3in LCD screen for framing and reviewing pictures.

However, the screen is not great for reviewing pictures as often times it would show them to be overexposed but they will look okay once transferred to a computer.

On the back are the usual array of buttons for various functions.

All buttons are within easy reach and if you’ve used a Canon camera in the past, you should be instantly familiar with the interface and menu.

SIMPLE: : The A2100's mode dial makes it easy to switch back and forth between different shooting modes.

On the top are the power switch, mode dial and the shutter buttons. Switching between the 10 modes is made easy with the dial.

Among the modes featured is Automatic Scene detection, pretty common in many of the compact cameras released this year.

Basically, the mode lets the camera choose the right settings for any scene, which is perfect for beginners.

If you want a little more hands on approach with your pictures, there’s Program mode. In this mode, you’ll have control over the camera’s various settings including the ISO level, white balance and autofocus.

Unfortunately, the mode doesn’t offer the flexibility of a full manual mode or Aperture Priority. Users who want more creative control over their pictures may want to consider the Canon PowerShot G10.

A reliable shooter

The A2100 has a 6x optical zoom lens that offers a focal length of 36 - 216mm — it’s a rather diverse range that covers both wide and telephoto ends of the spectrum.

Though it doesn’t excel when it comes to taking wideangle shots, but its long telephoto range should prove useful for shooting faraway subjects.

There is a minor barrel distortion at the widest end of the lens but this only affects pictures of buildings and shouldn’t get in the way when photographing people.

Autofocusing speeds were decent and it often took less than a fraction of a second to lock on to subjects.

And although it locks on very quickly when shooting outdoors, it took a second longer to focus when indoors or in particularly dark environments.

We were quite pleased with the photos we took during our outdoor excursion as the camera captured lots of detail with rich colours.

The camera handled chromatic aberration rather well even when we took shots directly under the sun.

In terms of flash performance, the camera lights up a scene well enough to capture objects in a dark room.

However, you’ve to time your shots as the camera’s three-second flash recharge cycle could cause you to miss important moments.

We were quite impressed by the camera’s face detection feature. It locks almost instantly to faces and even tracks them should they move or if you reframe the shot.

Image stabilisation has always been a grey area for me as I can’t really tell if it makes a big difference to my shots.

More often than not the camera boosts up the ISO level to increase light sensitivity and in turn, capture shake-free pictures.

However, there is a catch — increasing the ISO level also introduces more noise in pictures.

That being said, the camera’s noise performance is very mediocre. It takes fairly decent and noise free images from ISO 80 to 200 but the picture quality degrades a little as noise starts to creep in at ISO 400.

ISO 800 still looked fairly acceptable though there is noticeable loss in detail while ISO 1600 removes too much detail .

It is pretty clear that the A2100 isn’t a camera that’s for capturing videos as it only supports resolution of up to 640 x 480 pixels at 30fps.

Videos aren’t silky smooth but are otherwise acceptable in quality though too much movement usually results in blurry videos.

Also, you can’t use the camera’s optical zoom while recording which further limits your options.

The camera is quick to adjust to different lighting conditions when moving from a dark to a bright environment.

However, the white balance took awhile to adjust so indoor shots were slightly off colour but became gradually more balanced after a few seconds.

Conclusion

All in all, the Canon PowerShot A2100 IS is just an average point-and-shoot camera that’s easy to use for normal day-to-day photo taking.

It takes decent pictures in brightly lit conditions and captures a lot of detail with its 12.1-megapixel sensor.

However, it isn’t all that great for taking pictures indoors or in low light conditions.

Auto Scene mode will undoubtedly be favoured by newbies who are just getting into digital photography though experienced users may find the A2100 insufficient for their needs.

Overall, the A2100 is an entry level camera that should appeal to beginners.

Pros: Diverse 6x optical zoom lens; 12.1-megapixel; lots of Scene modes.

Cons: No handgrip; ISO performance isn’t terrific.

PowerShot A2100 IS

(Canon)

Compact digital camera

Sensor: 12.1 megapixels

Viewfinder: 3in LCD

Lens: 36 - 216mm, f/3.2 - 5.9 (35mm equivalent)

Shutter speed: 15sec - 1/1,600sec

ISO Range: 80 to 1600

Exposure modes: Program, Auto, Scene

Video mode: 640 x 480 pixels (30fps)

Battery: Two AA-size alkaline batteries

Storage: SD , SDHC

Interface: USB 2.0, AV output

Other features: Image stabilisation, Face detection

Dimensions: 10.2 x 6.35 x 31.9cm (w x h x d)

Weight: 185g

Website: www.canon.com.my

Price: RM949

Review unit courtesy of Canon Marketing (M) Sdn Bhd, (03) 7844-6000.

Nokia N97 3G smartphone

From The Star

‘N’ for Internet

Thursday July 30, 2009

We kick the tyres and peek under the hood of the N97 to see if its lives up to its billing as a powerhouse smartphone.

By STEFAN NAIDU

THE Nokia N97 has been keenly awaited since its worldwide introduction late last year as it was touted to be the next big thing in the mobile market by many observers.

The phone is laden with features and it is bound to be a Herculean task to condense all the features and functions in one sitting so there is little space to waste.

Sliding tilter?

The first thing you will notice about this model is what Nokia officials call a “sliding-tilt” phone. This means that you push one side forward and it tilts up to give you that mini-desktop look and feel, which I personally think is excellent for all kinds of situations.

A Qwerty keyboard has always been a requirement for me as I like to feel buttons beneath my fingertips when I am typing an SMS, e-mail or URL.

HANDY: The N97 comes with a slide out Qwerty keyboard.

This particular keyboard is a tad small for my big fingers but after a few days I was typing quite fluently. Beyond the Qwerty keyboard, the sole traditional button is the silver menu button. Side buttons include a lock button, volume control and camera toggle.

I was a little concerned about the wear and tear with the sliding-tilt hinge. Nokia have said that the hinge is made out of extremely sturdy material and that the phone has passed vigorous performance and drop tests.

I can say that it has passed my own accidental drop tests and the hinge does look and feel pretty strong.

The only real issue I had with the physical characteristics of the N97 was the back cover and battery, both of which are unrealistically hard to remove and replace.

Having tried this on a variety of people with different finger sizes and varying lengths of fingernails, I have concluded that it is near impossible to take out the battery without a prying mechanism. Tragic.

Online sensation

Built for the Internet, the N97 allocates the majority of its touchable home screen to movable and customisable widgets for quick access to your online needs.

Users are able to put their widgets in specific “rows” and there are around five rows in total. It was really useful having a link to online news and social networking sites.

Given the relative speed of fixed line broadband these days, many a time I was able to go online and check for updates faster on my mobile than on my laptop.

It is especially useful when you are on the go and need information quickly. Its always easier to prove a point or win an argument when you have Google embedded on the front screen of your phone.

It would be practical to consider a mobile broadband plan to get the most out of the N97 without slowly bleeding your wallet dry paying off the data charges.

Rocket science?

The resistive touch technology coupled with Nokia’s software makes for a very elegant combination. Navigating is by no means second nature, there are some hurdles in figuring out exactly how the web browser works.

One example is the zoom. There is a vertical tab that allows you to zoom in and out but, at least initially, you are not sure which part of the webpage it will zoom in to.

I still think that a Nokia phone is the one of the more user-friendly phones you can buy. This model has stayed true to that.

However as more and more functions get added to phones like this one, it just takes longer to find what you are looking for.

There were some bugs in the N97’s software post-release and I did ­experience some hanging and other minor glitches. According to Nokia officials, those imperfections were addressed in the first software update that is now available.

Wait, there is more

I took countless pictures and videos in the short time I had this phone with me. With 32GB of memory on board I never even thought about whether I had enough space for all of it.

The camera is just about as good as it gets on a phone and the video ­quality is quite impressive.

Given this, it was surprising that the voice recorder was not nearly as high end in terms of sound recording quality as I thought it would be. Some recordings turned out quite muffled.

The biggest disappointments were the speakers. The music output (specifically the bass) left something to be desired and you could barely make out what the other person is saying when you turn on the ­speakerphone at full volume.

My guess is that Nokia had packed far too much in this phone already and therefore the speakers were more of an afterthought (much like the removal process for the back cover and battery).

Conclusion

There is an inherent charm in the N97 that is inescapable. From placing it on a table and writing an SMS to surfing on a fantastically long landscape mode, it was all quite memorable as far as phones go.

Also, I thought the price was quite reasonable considering the usual trend with new releases of high-end and feature filled devices. That is not to say I consider it cheap though.

All in all, I thoroughly enjoyed my time with the phone and would recommend it to anyone looking for a powerhouse smartphone.

Pros: Unique sliding tilt; great to surf on; excellent fusion of Qwerty keyboard and touch technology.

Cons: Substandard speakers; cumbersome battery cover.

N97

(Nokia)

3G smartphone

Camera: 5-megapixels

Display: 3.5in (640 x 360-pixels)

Messaging: SMS, MMS, e-mail

Connectivity: WLAN, HSDPA, USB, Bluetooth

Memory: 32GB internal memory, MicroSD slot

Standby/talk time: 400 hours/360 minutes

Dimensions: 55.3 x 15.9 x 117.2mm (w x d x h)

Other features: Widgets, A-GPS

Price: RM2,480

Review unit courtesy of Nokia Malaysia, 1-300-88-1600.

Laman Web Datin Paduka Seri Rosmah Mansor



Ogos 4, 09 12:26pm

Rosmah lancar laman web peribadi dengan 13 bahasa
kemaskini 3.46pm 
Wanita pertama negara Rosmah Mansor melancarkan laman web peribadinya di alamat Pejabat Perdana Menteri (PMO), dipercayai antaranya untuk menangkis paparan negatif terhadapnya di internet.

Laman webnya di www.pmo.gov.my/datinrosmah memuatkan biodata beliau, berita dan aktiviti bergambar, koleksi teks ucapan, diari, keratan akhbar dan galeri video.

Melalui lama web ini, para pengunjung boleh mengakses beberapa laman web lain pembabitan sosialnya seperti Badan Amal dan Kebajikan Tenaga Isteri-Isteri Menteri dan Timbalan Menteri (Bakti), Permata Negara, Permata Pintar, Yayasan Pembangunan Anak-anak Yatim dan Miskin (Pemangkin), Yayasan Aids Kebangsaan dan Universiti Industri Selangor (Unisel).

Dengan laman web Rosmah ini, kali pertama isteri seseorang perdana menteri Malaysia mempunyai seksyen rasmi di laman web Pejabat Perdana Menteri.

Selain dalam bahasa Malaysia dan Inggeris, laman web itu boleh juga dicapai dalam 11 bahasa utama dunia menggunakan perisian penterjemah automatik di internet.

Laman web yang dibangunkan oleh Bahagian Sistem Maklumat Pengurusan Ketua Eksekutif (SMPKE) PMO itu juga akan ditambah dari semasa ke semasa, seperti aplikasi interaktif dan maklum
balas, sekiranya terdapat permintaan.

Ketika merasmikan laman web tersebut, Rosmah menyeru pengguna internet supaya bijak menapis maklumat dan tidak mudah
terpengaruh dengan mesej berbau fitnah dan hasutan, laporBernama.

Tambahnya, trend masa kini menunjukkan kemajuan teknologi
maklumat digunakan untuk menyebarkan fitnah dan dakyah.

"Kemajuan teknologi maklumat seharusnya digunakan dengan sebaik mungkin dan secara bijak untuk dimanfaatkan," beliau dipetik berkata di Putrajaya hari ini. 

Awal Jun lalu, Rosmah menjadi sasaran kempen memburuk-burukkan beliau melalui beberapa klip video dengan menggelarkan isteri Perdana Menteri Datuk Seri Najib Razak sebagai "perempuan puaka" dengan tuduhan-tuduhan berat.

Sebelum itu foto beliau kelihatan bercium pipi dengan bintang filem tersohor Shah Rukh Khan turut disebarkan secara meluas di internet, selain akuan bersumpah dan artikel karya Raja Petra Kamaruddin yang mengaitkan beliau dengan pembunuhan Altantuya Shaariibuu.

Rosmah menafikan pembabitan dengan kes wanita Mongolia itu.

Prime Minister's wife Datin Seri Rosmah Mansor clicking the mouse to launch the web page at Prime Minister Office in Putrajaya Tuesday.

PETALING JAYA: Datin Seri Rosmah Mansor has launched her own website for Malaysians to get to know her better in her role and duties as the Prime Minister’s wife.

The website, at www.pmo.gov.my/datinrosmah, includes news, pictures, speeches, newspaper articles and videos.

It is available in Bahasa Malaysia, English and other languages.

Announcing the website, Rosmah urged Malaysians to “filter” the information they get on the Internet and not be “influenced by messages with elements of slander.”

http://thestar.com.my/news/story.asp?file=/2009/8/4/nation/20090804113435&sec=nation


Bagaimana menggunakan database

Database amat berguna dalam kerja-kerja mengurus dan mengawal maklumat. Untuk menggunakan database dengan cekap, pengguna perlu memahami gambaran kasar bagaimana database berfungsi.

Terdapat berbagai jenis database; Hirarki, Network dan Relational. Yang popular dan lazim digunakan pada masa sekarang adalah Relational. Kewujudan perisian percuma seperti Linux dan MySQL telah merancakkan lagi penggunaan database di kalangan pengguna Internet.

Maksud Relational adalah database yang mengambil konsep tabular data representation (data disusun dalam bentuk table/jadual, seperti jadual kelas contohnya). Konsep ini bukanlah sesuatu yang asing kepada pengguna komputer di pejabat. Rata-rata pengguna telah biasa menggunakan lampiran kerja MS Excel yang juga berkosepkan tabular data representation.


Di dalam Relational Database, satu table mewakili satu set gabungan data yang membentuk entiti tertentu. Contohnya table 'pelajar' mengandungi lajur yang mewakili ciri-ciri pengenalan pelajar (nama, no ic, alamat, email) dan baris (setiap satu baris mewakili maklumat seorang pelajar berdasarkan ciri-ciri tadi). Satu Relational Database boleh mengandungi banyak table. Contohnya Database bagi Sistem Pendaftaran Pelajar mungkin mengandungi table 'pelajar', 'jurusan', 'kelas' dan sebagainya.

MySQL adalah contoh Relational Database. Dalam sistem database MySQL, satu komputer akan berfungsi sebagai hos dan komputer2 laing yang berhubung dengannya berfungsi sebagai klien.

Untuk memahami dengan lebih lanjut, anda boleh mencuba MySQL yang dihoskan secara percuma di http://www.freesql.org/

Pakej perisian MS Office juga mempunyai perisian MS Access yang turut menggunakan konsep Relational Database. Bagaimanapun tujuan asas MS Access adalah untuk pengguna komputer peribadi sahaja. Maka ia tidak direka untuk menampung ramai pengguna dalam sesuatu jaringan komputer.

Walaubagaimanapun sifat MS Access yang mudah dan ramah pengguna menjadikannya popular di kalangan pengguna komputer peribadi dan tidak hairan jika usaha menggabungkan MS Access dan MySQL telah dibuat. Melalui penggunaan perisian pemandu MyODBC, anda boleh menggabungkan MS Access (sebagai Front End) dan MySQL (sebagai Back End).


Maksud Internet



Istilah Internet adalah merujuk kepada Rangkaian Komputer Global (Global connection of computer networks).

Projek Internet sebenarnya bermula seawal tahun 1960an melalui ARPAnet (Advanced Research Project Agency atau Agensi Projek Penyelidikan Termaju), sebuah projek yang mendapat biaya kerajaan US untuk mewujudkan rangkaian komputer di antara empat universiti perintis; Universiti California, Universiti Utah, Universiti California Santa Barbara dan Institut Kajian Stanford (sekarang Universiti Stanford).


Pada tahun 1985, ARPAnet dihubungkan kepada NSFnet (Rangkaian komputer untuk kegunaan kajian sains). Hubungan ini digelar sebagai Internet dan dikatakan sebagai cantuman perkataan Inter dan Network. Rangkaian tersebut terus berkembang dan akronimnya kekal sebagai Internet.

Internet beroperasi menggunakan dua protokol (tatacara komunikasi) utama iaitu TCP dan IP.

TCP maksudnya Transfer Control Protocol. Dalam bahasa mudah, ia menggariskan tatacara bagaimana data dipindahkan dari satu komputer ke komputer yang lain.

IP bermaksud Internet Protocol. Dalam bahasa mudah, ia menggariskan tatacara bagaimana sesuatu komputer itu menyertai jaringan komputer dan dapat dikenali oleh komputer lain yang berada dalam jaringan tersebut.

Secara mudahnya TCP dan IP ibarat Posmen,Surat dan Alamat Rumah. Setiap surat perlu ada nama penerima dan alamatnya. Posmen akan membawa surat melalui apa jua laluan asalkan dapat sampai kepada penerimanya. Jika penerima tidak wujud, posmen akan pulangkan semula surat kepada penghantar atau pejabat pos asalnya.

Topik berkaitan:

Maksud Sistem (System)

Kita lazim mendengar perkataan 'sistem' di dalam perbualan yang berkaitan dengan komputer. Namun seringkali mereka yang mengucapkan perkataan 'sistem' itu sendiri tidak tahu apa yang dimaksudkan oleh perkataan tersebut.

Sistem bermaksud satu himpunan komponen kerja yang saling berkaitan dan bekerjasama untuk mendapai matlamat himpunan mereka.

'System is a collection of components that work together to achieve their common objective'.

Saya gemar memberikan contoh kenderaan untuk memberi kefahaman lanjut pelajar tentang maksud sistem.

Kenderaan contohnya kereta merupakan gabungan komponen tertentu yang membantu membawa manusia bergerak dari satu tempat ke tempat yang lain. Secara ringkasnya, ada komponen enjin, komponen tayar, komponen brek, komponen pecutan, komponen gear, komponen lampu, komponen pendingin dan bermacam-macam lagi.

Komponen ini saling bekerjasama, umpamanya apabila pemandu menekan pemacu (accelerator), minyak akan disalurkan ke enjin, enjin akan membakar lebih kuat dan tayar akan bergerak lebih laju. Kesepaduan ini dinamakan 'Goal Congruence'.

Adakalanya sesuatu komponen itu sifatnya melawan sifat komponen yang lain. Contoh yang ketara ialah antara komponen pecutan dan komponen brek. Lazimnya, kaki kita akan menekan salah satu pedal (pecut atau brek) dan bukan kedua-duanya sekali. Apa akan jadi kalau ditekan kedua-duanya sekali? Jadilah 'Goal Conflict'.

Seorang pemandu yang baik tentulah akan memastikan 'Goal Congruence' wujud keseluruhannya. Tanyalah Michael Schumacher bagaimana 'sistem' ini membantunya menjuarai Formula 1.


Gallery: fb.me/NotaMotivasi - Koleksi Motivasi, Kata Mutiara dan Kata Minda.

Maksud Broadband

Dalam bidang telekomunikasi broadband merujuk kepada kaedah menghantar isyarat menggunakan frekuensi yang bersaiz lebar. Dalam bidang komunikasi data, modem analog yang menggunakan talian telefon berupaya menghantar data 56 kilobit per saat.

Melalui kaedah ADSL (Asynchronous Digital Subscriber Line) contohnya, talian yang sama berupaya membawa data sebesar beberapa megabits per saat.Dalam contoh ini, data telah dipecahkan kepada cebisan-cebisan dan dihantar ke destinasi secara serentak agar kadar pemindahan menjadi lebih effektif. Hasilnya komputer berupaya memindahkan fail bersaiz besar seperti format audio dan video dalam masa yang singkat.

Monday, August 03, 2009

Pengenalan-Database System (Sistem Pangkalan Data)


Database bermaksud satu cara menyimpan dan menguruskan data secara terkawal dan berpusat.

Peranan Database menjadi penting apabila organisasi mempunyai data yang banyak dan berkait antara satu sama lain. Antara kelebihan Database:

1) Simpanan dan kawalan data secara berpusat
2) Pengurusan data secara cekap
3) Mengelakkan gejala data yang disimpan berulang2 dan data yang disimpan berselerak
4) Meningkatkan penggunaan data effektif dengan membenarkan data dicapai oleh perisian yang lain.

Perisian Database boleh dijalankan secara standalone (bersendirian) ataupun secara networked (berangkaian). Sistem secara standalone (bersendirian) turut dikenali sebagai desktop database (pangkalan data (komputer)"atas meja"). Sistem berangkaian pula kebiasaanya berdasarkan Client-Server Architecture (Senibina Pelanggan-Pelayan). Pada masa kini, Networked Database System (Sistem Pangkalan Data Berangkaian) digunakan dengan meluas melalui Internet

Antara Desktop Database yang popular adalah Microsoft Access, Foxpro dan File Maker.

Antara Networked Database yang popular adalah Microsoft SQL, MySQL, PostGre dan Oracle.

Pengenalan-File Transfer Protocol (FTP)

File Transfer Protocol (FTP) adalah salah satu perkhidmatan yang terdapat di dalam Internet yang membolehkan fail (data file) dipindahkan dari satu komputer ke komputer yang lain. Perkhidmatan FTP bersifat Client-Server iaitu satu komputer berfungsi sebagai hos FTP dan satu (atau banyak) komputer lagi berfungsi sebagai klien.

Sunday, August 02, 2009

Masalah-ada hantu di rumah saya

Biasa kita mendengar kisah orang yang membeli rumah dan kemudiannya mendapati rumah itu dihuni pula makhluk lain. Dilemma melanda samada nak menghalau atau meninggalkan sahaja rumah itu.

Jangan rasa pelik jika komputer juga boleh jadi berhantu. Ya, memang sesuatu yang menyulitkan dan menyusahkan apabila mendapati komputer milik kita dihuni oleh makhluk lain yang hidup dengan caranya sendiri hingga kadang-kadang dan sememangnya mengancam 'private life' kita.

Exterminate-it.com mengklasifikan hantu komputer (atau istilah akademiknya, Malicious Software a.k.a 'Malware') kepada beberapa jenis:

1) Trojan
Trojan adalah Malware yang menyamar sebagai program yang sah tetapi disebalik itu ia melakukan kerja-kerja merosakkan sistem komputer. Ia tidak bercambah tetapi kewujudan seekor dua Trojan dalam sistem komputer sudah cukup untuk melemahkan sistem tersebut.


2) Spyware
Spyware adalah program pengendap yang bertujuan mengumpulkan profil pemilik komputer tersebut. Secara diam-diam Spyware menghantar laporan kepada tuannya. Trojan juga boleh menjadi Spyware jika ia turut membuat hubungan luar dari komputer yang dihuninya dan menyampaikan maklumat berkenaan komputer tersebut.

3) Backdoor
Backdoor, sepertimana namanya, membuka 'pintu belakang' sistem komputer yang dicerobohinya; membolehkan sistem tersebut ditembusi dan 'dianiaya' oleh si penceroboh.


4) RAT
Remote Access Tool adalah program yang membantu penggodam komputer menguasai komputer yang diserangnya seterusnya menjadikan komputer mangsa itu sebagai 'zombie' (mayat hidup). Maksudnya, sistem komputer itu dapat dikawal dan digunakan untuk kegiatan jenayah siber seperti melancarkan serangan ke atas komputer lain ataupun menghantar maklumat propaganda ke jaringan sistem komputer.


5) DOS
Denial Of Service Attack adalah satu bentuk serangan yang bertujuan melemahkan Laman Web dan mengakibatkan sistem pertahanannya ditembusi dan dikuasai oleh penggodam web.


Persoalannya bagaimana program2 ini boleh masuk dan menumpang di dalam komputer kita? Barangkali kita tidak 'mengunci' rumah komputer kita dengan baik dan boleh jadi juga kita leka meluncur di sana sini dalam Internet tanpa sedar laluan yang kita tempuh itu sebenarnya tidak selamat. Samalah halnya seperti periuk api (mines). Kita takkan tahu ada periuk api sehinggalah periuk api itu meletup. Janganlah halnya begitu!