Monday, 30 April 2012


Penggunaan Internet oleh Guru

i.)            meluaskan pengetahuan guru

Kemudahan Internet juga memberi peluang kepada guru mempertingkatkan tahap ilmu pengetahuan mereka melalui pelbagai maklumat yang berkaitan. Sebagai contoh para guru boleh mengakses bahan-bahan akedemik dan mencari maklumat pendidikan melalui perpustakaan siber universiti-universiti tempatan dan luar negara atau
kemudahan USENET yang disediakan oleh Internet. Di samping itu, para guru dapat membincangkan isu semasa pengajaran dengan guru-guru lain di seluruh negara mengenai program pendidikan yang telah berjaya.

ii.)           sebagai Bahan Bantu Mengajar


Pendidikan berasaskan Internet juga boleh dikategorikan sebagai proses pengajaran dan pembelajaran. Ini memandangkan kemudahan Internet bukan sahaja menawarkan komponen-komponen lain seperti laman-laman Web, malah menyediakan sumber pendidikan berbentuk teks yang diperkayakan dengan unsur-unsur lain sepertigrafik, animasi atau audio visual. Kaedah pendidikan melalui Internet ini memerlukan penglibatan aktif para penggunanya di samping mengetengahkan konsep interaktif. Konsep tersebut bukan sahaja sesuai menyampaikan sumber-sumber maklumat berbentuk pendidikan, malah sesuai digunakan untuk menyampaikan program latihan dan perkhidmatan pendidikan dalam talian. Program-program pendidikan dan latihan secara interaktif menerusiInternet sama ada yang dikendalikan oleh pihak sekolah atau institusi pengajian tinggi dan pihak berkuasapendidikan memerlukan penglibatan secara langsung di antara pihak penerima dan penyampainya. Sebagai contoh mengakseskan nota-nota kuliah, menghantar dan menyemak tugasan boleh dilakukan menerusi talian.Pembelajaran ini dikatakan lebih memanfaatkan pelajar kerana walau apapun kaedah pengajaran yang dipilih,penglibatan pelajar secara aktif perlulah diberi keutamaan. Penglibatan secara aktif oleh pelajar dalammengakseskan bahan-bahan yang diperlu dalam Internet berupaya memupuk dan memperkembangkan kemahiran berfikir dan kreativiti di kalangan pelajar (Rashidi dan Abdul Razak 1997).



http://www.ppdbesut.net


Perkongsian Maklumat dengan Internet

Projek Jaringan Pendidikan (JP) di bawah kelolaan makmal Teknologi Komputer, Kementerian Pendidikan dan MIMOS merupakan satu usaha penting yang menyediakan kemudahan dan perkhidmatan rangkaian kepada pelajar dan pendidik. Projek ini merupakan salah satu aktiviti dalam program Komputer Dalam Pendidikan oleh Kementerian Pendidikan. Matlamat utama kewujudan projek ini adalah untuk mewujudkan perkongsian maklumat serta sekolah yang kaya dengan maklumat dan seterusnya meningkatkan mutu pendidikan bertaraf dunia. Menerusi projek ini, guru boleh memasukkan aktiviti-aktiviti kreatif dan inovatif yang berasaskan teknologi maklumat. Di dalam projek ini juga, terdapat kemudahan ‘mailing list’ (kumpulan perbincangan berasaskan topik yang menggunakan e-mel sebagai kaedah komunikasi) yang menyediakan kemudahan ‘listserv’ atau senarai perkhidmatan dan terdapat lebih 3000 ‘listserv’ di dalam Internet yang boleh difikirkan oleh manusia.



http://www.ppdbesut.net

Penggunaan Laman Web Sekolah


Teknologi Internet juga mampu menyediakan kemudahan kepada para guru dan pelajar untuk mengambil bahagian di dalam pelbagai aktiviti seperti pembangunan laman Web di setiap sekolah. Sudah ramai yang memperakui bahawa tapak-tapak Web boleh dijadikan sebagai saluran berkesan untuk mewartakan segala kegiatan yang dilaksanakan di sekolah-sekolah kepada para pelajar dan guru sekolah tersebut. Di samping itu laman Web tersebut juga boleh diakses oleh para pelajar, guru-guru dan pihak lain yang berminat dari seluruh negara. Jika kemudahan ini diperluaskan lagi, ibu bapa hanya perlu melanggani laman Web tersebut untuk
mengetahui segala perkembangan bidang akademik atau ko-kurikulum anak-anak mereka tanpa berkunjung ke sekolah. Ibu bapa juga dapat menghubungi guru melalui e-mel yang didapati dari laman Web yang dikunjungi. Secara tidak langsung, hubungan ibu bapa dengan pihak sekolah dapat ditingkatkan. Oleh yang demikian, masalah-maslah disiplin pelajar yang memerlukan kerjasama antara pihak sekolah dengan mudahnya dapat ditangani. Ibu bapa tidak ada lagi alasan bahawa mereka sibuk dan tidak dapat berkunjung ke sekolah untuk berbincang tentang hal-hal anak-anak mereka. Guru mempunyai satu alternaltif lagi untuk berjumpa dengan ibu bapa anak muridnya.


http://www.ppdbesut.net

Internet Sebagai Sumber Rujukan

Kemudahan Internet juga telah memperkayakan lagi sumber-sumber maklumat. Tambahan pula, sebagai gedung ilmu yang luas sifatnya, kemudahan Internet mampu menyediakan sumber rujukan yang bersifat lebih
menyeluruh. Kandungannya turut mencakupi keperluan maklumat pendidikan semasa sama ada untuk kegunaan golongan profesional, pendidik, keluarga, pelajar dan orang ramai. Lebih dari itu, Internet turut menyediakan pelbagai bentuk maklumat yang sesuai untuk pelbagai program pendidikan. Pencapaian maklumat tersebut adalah cepat dan mudah dikendalikan. Contohnya, jika mengambil laman Web sebagai salah satu sumber maklumat pendidikan, maka dengan usaha yang agak mudah kita boleh mendapatkannya dengan sekelip mata. Usaha tersebut dapat direalisasikan kerana Internet sudah dilengkapi dengan komponen-komponen yang dapat membantu penggunanya seperti pelayar Web dan enjin pencarian atau Pencarian Maklumat Luas (Global Information Browsing) yang membolehkan pengguna melihat maklumat dengan mudah dan tidak kira di mana maklumat itu berada. Dengan itu, kategori laman-laman Web yang boleh disifatkan sebagai bermaklumat dan sesuai untuk tujuan pendidikan termasuklah laman Web bagi institusi pengajian tinggi maya, agensi berita, majalah dan akhbar dalam talian yang kandungan mereka ketengahkan bersifat lebih terperinci mudah dicapai. Kini bukan lagi satu khayalan apabila seseorang individu dengan mudah dapat melawat masuk ke dalam sebuah perpustakaan di seluruh dunia untuk pelbagai tujuan seperti mendapatkan sumber-sumber penyelidikan, pengajian rentas budaya, mempertingkatkan penguasaan bahasa asing, bertukar-tukar pendapat atau sekadar belajar dengan rakan sebaya. Contohnya jelas ketika ini apabila sudah terdapat perpustakaan elektronik di dalam Internet yang
boleh membantu para pelajar dan guru membuat tugasan penyelidikan mereka. Perpustakaan tersebut akan
menyediakan sebuah pintu masuk yang bersifat maya untuk membolehkan penggunanya mengakses pelbagai
sumber maklumat yang turut diperkayakan dengan unsur-unsur multimedia seperti teks, gambar, bunyi dan video yang pasti menyeronokkan pelajar. Di samping itu, terdapat pelbagai laman Web dalam Internet yang mempunyai perpustakaaan yang tersendiri yang dipanggil ‘virtual library’. Guru boleh mendapatkan maklumat atau bahan rujukan untuk tujuan pengajaran sebelum disampaikan dalam kelas. Dengan penggunaan Internet sebagai sumber untuk mendapatkan maklumat, sudah pastilah corak pengajaran dan pembelajaran dapat berlangsung dalam suasana yang menyeronokkan.

Penggunaan E-mel dalam Pendidikan


Penggunaan E-mel dalam Pendidikan

Aplikasi paling asas teknologi Internet yang boleh diketengahkan dalam bidang pendidikan khususnya di peringkat sekolah ialah aplikasi e-mel atau juga dikenali sebagai mel elektronik. Melalui aplikasi ini, pelajarpelajar boleh menyatakan sebarang masalah berkaitan dengan apa yang telah dipelajari dengan serta-merta. Contohnya, pelajar boleh menanya guru soalan atau masalah yang dihadapi semasa belajar di perpustakaan atau di rumah melalui e-mel. Dengan itu, guru boleh menjawab atau membantu pelajar tersebut menyelesaikan masalah yang dihadapi melalui e-mel atau guru boleh menjadikan soalan atau masalah yang ditanya itu sebagai persediaan untuk pengajaran pada hari yang berikutnya. Sebaliknya, guru juga boleh mengetahui respon pelajar terhadap kerja rumah yang diberi melalui e-mel.

Menurut Dr. Jane Lasarenko (1997), kebaikan yang utama menggalakkan pelajar berkomunikasi dengan guru melalui e-mel ialah ini dapat menanam semangat yang tinggi di kalangan pelajar dalam pembelajaran mereka. Bukan itu sahaja, pelajar tidak lagi ada alasan untuk menghantar kerja rumah lewat kerana mereka boleh menggunakan e-mel untuk menghantar kerja rumah pada hari yang ditetapkan sehingga tamatnya hari tersebut.
Selain itu, Cisco System Inc. iaitu sebuah syarikat teknologi maklumat yang menceburi bidang pendidikan menyebut bahawa melalui e-mel, para guru dan pelajar juga boleh berkomunikasi dengan sekolah-sekolah di seluruh negara bahkan di serata dunia hanya melalui makmal komputer atau bilik-bilik darjah. (Jamaludin Badusah et al. 2000). Aplikasi ini membolehkan mereka bertukar-tukar mesej semasa, berkongsi idea dan bahanbahan pendidikan di antara satu sama lain memandangkan e-mel bukan sahaja cepat malahan juga murah berbanding dengan mel biasa atau menggunakan faksimili.

Monday, 9 April 2012

Software engineering



Software engineering


             Software engineering (SE) is the application of a systematic, disciplined, quantifiable approach to the development, operation, and maintenance of software, and the study of these approaches; that is, the application of engineering to software. It is the application of engineering to software because it integrates significant mathematics, computer science and practices whose origins are in engineering. It is also defined as a systematic approach to the analysis, design, assessment, implementation, testing, maintenance and reengineering of software, that is, the application of engineering to software. The term software engineering first appeared in the 1968 NATO Software Engineering Conference, and was meant to provoke thought regarding the perceived "software crisis" at the time.
Software development, a much used and more generic term, does not necessarily subsume the engineering paradigm. Although it is questionable what impact it has had on actual software development over the last 40 years, the field's future looks bright according to Money Magazine and Salary.com, which rated "software engineer" as the best job in the United States in 2006.


History

            When the first modern digital computers appeared in the early 1940s, the instructions to make them operate were wired into the machine. Practitioners quickly realized that this design was not flexible and came up with the "stored program architecture" or von Neumann architecture. Thus the division between "hardware" and "software" began with abstraction being used to deal with the complexity of computing.
Programming languages started to appear in the 1950s and this was also another major step in abstraction. Major languages such as Fortran, ALGOL, and COBOL were released in the late 1950s to deal with scientific, algorithmic, and business problems respectively. E.W. Dijkstra wrote his seminal paper, "Go To Statement Considered Harmful", in 1968 and David Parnas introduced the key concept of modularity and information hiding in 1972 to help programmers deal with the ever increasing complexity of software systems. A software system for managing the hardware called an operating system was also introduced, most notably by Unix in 1969. In 1967, the Simula language introduced the object-oriented programming paradigm.
           These advances in software were met with more advances in computer hardware. In the mid 1970s, the microcomputer was introduced, making it economical for hobbyists to obtain a computer and write software for it. This in turn led to the now famous Personal Computer (PC) and Microsoft Windows. The Software Development Life Cycle or SDLC was also starting to appear as a consensus for centralized construction of software in the mid 1980s. The late 1970s and early 1980s saw the introduction of several new Simula-inspired object-oriented programming languages, including Smalltalk, Objective-C, and C++.
Open-source software started to appear in the early 90s in the form of Linux and other software introducing the "bazaar" or decentralized style of constructing software.Then the World Wide Web and the popularization of the Internet hit in the mid 90s, changing the engineering of software once again. Distributed systems gained sway as a way to design systems, and the Java programming language was introduced with its own virtual machine as another step in abstraction. Programmers collaborated and wrote the Agile Manifesto, which favored more lightweight processes to create cheaper and more timely software.
The current definition of software engineering is still being debated by practitioners today as they struggle to come up with ways to produce software that is "cheaper, better, faster". Cost reduction has been a primary focus of the IT industry since the 1990s. Total cost of ownership represents the costs of more than just acquisition. It includes things like productivity impediments, upkeep efforts, and resources needed to support infrastructure.


 http://en.wikipedia.org/wiki/Software_engineering

Sunday, 8 April 2012

NETWORK CABLING



Network Cabling

Cable is the medium through which information usually moves from one network device to another. There are several types of cable which are commonly used with LANs. In some cases, a network will utilize only one type of cable, other networks will use a variety of cable types. The type of cable chosen for a network is related to the network's topology, protocol, and size. Understanding the characteristics of different types of cable and how they relate to other aspects of a network is necessary for the development of a successful network.
The following sections discuss the types of cables used in networks and other related topics.
  • Unshielded Twisted Pair (UTP) Cable
  • Shielded Twisted Pair (STP) Cable
  • Coaxial Cable
  • Fiber Optic Cable
  • Cable Installation Guides
  • Wireless LANs
  • Unshielded Twisted Pair (UTP) Cable
Twisted pair cabling comes in two varieties: shielded and unshielded. Unshielded twisted pair (UTP) is the most popular and is generally the best option for school networks (See fig. 1).

Fig.1. Unshielded twisted pair
The quality of UTP may vary from telephone-grade wire to extremely high-speed cable. The cable has four pairs of wires inside the jacket. Each pair is twisted with a different number of twists per inch to help eliminate interference from adjacent pairs and other electrical devices. The tighter the twisting, the higher the supported transmission rate and the greater the cost per foot. The EIA/TIA (Electronic Industry Association/Telecommunication Industry Association) has established standards of UTP and rated six categories of wire (additional categories are emerging).




Categories of Unshielded Twisted Pair

Category
Speed
Use
1
1 Mbps
Voice Only (Telephone Wire)
2
4 Mbps
LocalTalk & Telephone (Rarely used)
3
16 Mbps
10BaseT Ethernet
4
20 Mbps
Token Ring (Rarely used)
5
100 Mbps (2 pair)
100BaseT Ethernet
1000 Mbps (4 pair)
Gigabit Ethernet
5e
1,000 Mbps
Gigabit Ethernet
6
10,000 Mbps
Gigabit Ethernet

Unshielded Twisted Pair Connector

The standard connector for unshielded twisted pair cabling is an RJ-45 connector. This is a plastic connector that looks like a large telephone-style connector (See fig. 2). A slot allows the RJ-45 to be inserted only one way. RJ stands for Registered Jack, implying that the connector follows a standard borrowed from the telephone industry. This standard designates which wire goes with each pin inside the connector.

Fig. 2. RJ-45 connector

Shielded Twisted Pair (STP) Cable

Although UTP cable is the least expensive cable, it may be susceptible to radio and electrical frequency interference (it should not be too close to electric motors, fluorescent lights, etc.). If you must place cable in environments with lots of potential interference, or if you must place cable in extremely sensitive environments that may be susceptible to the electrical current in the UTP, shielded twisted pair may be the solution. Shielded cables can also help to extend the maximum distance of the cables.
Shielded twisted pair cable is available in three different configurations:
  1. Each pair of wires is individually shielded with foil.
  2. There is a foil or braid shield inside the jacket covering all wires (as a group).
  3. There is a shield around each individual pair, as well as around the entire group of wires (referred to as double shield twisted pair).

Coaxial Cable

Coaxial cabling has a single copper conductor at its center. A plastic layer provides insulation between the center conductor and a braided metal shield (See fig. 3). The metal shield helps to block any outside interference from fluorescent lights, motors, and other computers.

Fig. 3. Coaxial cable
Although coaxial cabling is difficult to install, it is highly resistant to signal interference. In addition, it can support greater cable lengths between network devices than twisted pair cable. The two types of coaxial cabling are thick coaxial and thin coaxial.
Thin coaxial cable is also referred to as thinnet. 10Base2 refers to the specifications for thin coaxial cable carrying Ethernet signals. The 2 refers to the approximate maximum segment length being 200 meters. In actual fact the maximum segment length is 185 meters. Thin coaxial cable has been popular in school networks, especially linear bus networks.
Thick coaxial cable is also referred to as thicknet. 10Base5 refers to the specifications for thick coaxial cable carrying Ethernet signals. The 5 refers to the maximum segment length being 500 meters. Thick coaxial cable has an extra protective plastic cover that helps keep moisture away from the center conductor. This makes thick coaxial a great choice when running longer lengths in a linear bus network. One disadvantage of thick coaxial is that it does not bend easily and is difficult to install.

Coaxial Cable Connectors

The most common type of connector used with coaxial cables is the Bayone-Neill-Concelman (BNC) connector (See fig. 4). Different types of adapters are available for BNC connectors, including a T-connector, barrel connector, and terminator. Connectors on the cable are the weakest points in any network. To help avoid problems with your network, always use the BNC connectors that crimp, rather screw, onto the cable.

Fig. 4. BNC connector

Fiber Optic Cable

Fiber optic cabling consists of a center glass core surrounded by several layers of protective materials (See fig. 5). It transmits light rather than electronic signals eliminating the problem of electrical interference. This makes it ideal for certain environments that contain a large amount of electrical interference. It has also made it the standard for connecting networks between buildings, due to its immunity to the effects of moisture and lighting.
Fiber optic cable has the ability to transmit signals over much longer distances than coaxial and twisted pair. It also has the capability to carry information at vastly greater speeds. This capacity broadens communication possibilities to include services such as video conferencing and interactive services. The cost of fiber optic cabling is comparable to copper cabling; however, it is more difficult to install and modify. 10BaseF refers to the specifications for fiber optic cable carrying Ethernet signals.
The center core of fiber cables is made from glass or plastic fibers (see fig 5). A plastic coating then cushions the fiber center, and kevlar fibers help to strengthen the cables and prevent breakage. The outer insulating jacket made of teflon or PVC.

Fig. 5. Fiber optic cable
There are two common types of fiber cables -- single mode and multimode. Multimode cable has a larger diameter; however, both cables provide high bandwidth at high speeds. Single mode can provide more distance, but it is more expensive.


http://fcit.usf.edu/network/chap4/chap4.htm

Telecommunication


Telecommunication


Telecommunication is the transmission of information over significant distances to
communicate. In earlier times, telecommunications involved the use of visual signals, such as
messages via coded drumbeats, lung-blown horns, or sent by loud whistles, for example. In the
modern age of electricity and electronics, telecommunications now also includes the use of
electrical devices such as the telegraph, telephone, and teleprinter, as well as the use of radio and
microwave communications, as well as fiber optics and their associated electronics, plus the use
of the orbiting satellites and the Internet.



http://en.wikipedia.org/wiki/Telecommunication