Computer Supported Cooperative Work

The term Computer Supported Cooperative Work (CSCW) was first used by Irene Greif and Paul M. Cashman in 1984, at a workshop attended by those interested in using technology to facilitate their work .. On the same occasion in 1987, Dr. Charles Findley presented the concept of collaborative learning-work. According, CSCW raised issues around how collaborative activities and coordination of computer technology can be supported therein. Some people equate with CSCW groupware, but others say that groupware refers to a concrete manifestation of a computer-based system, whereas CSCW focuses on the study of Kakas and techniques of groupware itself, including the effects that arise bail psychologically and socially. Proposed definitions emphasize the differences between these two concepts:
CSCWSalah a general matrix form of the conceptualization of CSCW systems is to examine the context of the use of the system. An example is the matrix of CSCW, which was first introduced in 1988 by Johansen, and also appeared on. The matrix is membagikonteks a "work" in two dimensions the time and location. Time dimension is divided into collaboration conducted at the same time (synchronous) or different (asynchronous). Dimensional locations are divided into collaboration conducted in the same place, or distributed.

Mobile Device

Mobile device consists of Lcd, Keypad, Battery, IC (Interface, Audio, Charge, Regulator, Flash) Ram, Cpu, Sim Card, micro-phone, Bluetooth, Antenna, Speaker, Power detector, RX Filters, etc..
and the following functions.

LCD
Liquid Crystal Display (LCD) display is a thin, flat-visual electronics that use light modulation properties of crystals. This component serves to display an image or any activity of a cell phone.

Key pad
This component serves as a tool that provides
command data to the CPU for processing and will be sent to the component
others involved in the mobile phone.

Battery
Function as a source of electrical current / voltage
required to provide electrical current to the phone.

IC
Interface: Function as a data controller who was ordered by the
CPU for Vibrator, Buzzer, light and act as an automatic switch in the
Mobile.
Audio: audio Ic as a function of processing the incoming voice signals from the IC
RF, amplified and transmitted to the Speaker, amplify the sound vibrations that have been
Mic converted into electrical vibration is then forwarded to the RF IC, running
command from the CPU and the audio IC also contained PCM (Pulse Code Module) and
Functioning EEPROM read code signals coming from the operator to
The phone IMEI is also adapted to store data that are permanent.
Charge: This component works automatically when charging
and it works just to fill the battry voltage is controlled by the CPU
through IC Regulator.
Regulator: Serves to adjust the voltage, in order to set appropriate
needs of each relevant component, as well as pengkontrol of IC
Charging is controlled by the CPU.
Flash: Data storage on Cellular Telephone, the nature
temporary because the data can be changed or added.

RAM
(Random Access Memory) stores data temporarily and help CPU.semakin performance of large-capacity RAM the better CPU performance.

CPU
Data processing centers located in all elements of
or components that work in such rule Cellular Telephone
related components to work as needed and can receive information
of each - each component Example: Order IC Power Supply for
supply voltage / current to all parts of Cellular Telephone, ordered
LCD to display the Activity on Cellular Telephone, ordered the IC
Flash to store the data and release it when needed, check
Sim card data from entering through the IC Power Supply, received the order of data
from the Keypad to the process.

Sim Card
Identity of each of the Cellular Telephone
active depending on the provider's sim card is used, by way of
processed by the CPU included in the phone.

Microphone
A tool to speak and the way it works is
convert sound vibrations into electrical vibrations so that the sound could be accepted
processed by other mobile phone components

Antenna
Serves as a catcher and transmitter signal wave received by the
phone.

Speaker
A device for the release of the previous vote was
electric vibrations and converted into sound by means of the IC Audio, which received
by the CPU to make a sound contained in the mobile phone.

Power detector
Is a transistor that detects, strength of Signal
and transmit data to the CPU for processing and then provide the data
related to all components, especially with hardware-related
Signal

RX filter
Serves as a filter / frequency divider will be
be broadcast before it is sent or reinforced by other components
contained in the mobile phone.

Operating System For Mobile

IOS
Apple's operating systems dominate the mobile operating systems share the use of the Apple handset is quite broad as well as iPhone, iPod Touch, and iPad. Coupled also with Apple gadget users active bersurfing ria in the Internet and use applications that consume data from the Internet plus Apple Marketting is quite unique in my opinion so it is not strange that Apple is above the top share of mobile operating systems

SYMBIAN OS
Before the IOS and Android is not known as of now, mobile Symbian OS Nokia arguably the king of the mobile OS market. But now the fallen are displaced by the IOS and Android. Although begitum, Symbian still has a large enough base in the mobile OS market because too many users. If there are no new innovations in Symbian, maybe too long a mobile OS will be dropped and living history


RIM OS
Who is not familiar with the RIM Blackberry OS. Maybe some people a little surprised to see RIM OS does not occupy a higher position (including me hehe ...), this may be due to the fact that Blackberry users are used by most corporate circles whose numbers are certainly not as much as other types of users, different from the IOS and Android has a larger user market. (Note: only in Indonesia ABG young children love to use my Blackberry i know)

WINDOWS MOBILE OS
Windows = Microsoft. Microsoft munkin arguably the king of his computer's operating system but not for mobile. Windows Mobile is also a new series that I heard not a lot of features that provide unique and well, lost to other competitors. Especially when compared to the Android mobile OS which is actually free, while Windows Mobile OS and IOS with the eleganannya. I think Microsoft should be melakakukan something innovative with their Windows Mobile OS if they want to get rid of their rivals.

ANDROID
Android with a unique logo that is "Robot Ijo" has actually been around a long time, but since the year 2009 with the rapid development of Android shot. Mobile OS from Google is providing a very broad freedom to developers and fully integrated with Google technology. Applications are available for Android also has a lot of Android users have so many variations in using the application in Android. With support from Google, the king of search engines and digital advertising, Android ranks second in mobile OS share.

Palm OS
The operating system used on the output PALM PDA.

Operating System For Computer

UBUNTU
Is one of the Debian-based Linux distributions. The Ubuntu project is officially sponsored by Canonical Ltd is a company owned by a South African cosmonaut Mark Shuttleworth

UNIX
SO is there for the very first computer. SO this is a parent of LINUX

LINUX
First developed by Linus Torvalds. Is an open source operating system means it can be developed by everyone freely. Derivatives known as linux or linux distro many kinds. Maybe Linux is the operating system the most. Some of them are: Debian, Suse, Red Hat (Fedora), Slackware, Ubuntu, Backtrack, etc.

DOS
Operating system is the forerunner of Microsoft Windows. His trademark is a white text on a black background. If you want to try to pass the Windows Start - Run, then type cmd.

FREE BSD
Created by the University of Berkeley. Operating systems are almost the same as linux.

NOVELL OPERATING SYSTEM
Operating system is made by the Novell Corporation. The operating system once used by the Faculty of Mathematics and Science UGM for KRS-In Key Entry students.

SOLARIS
Developed by Sun Microsystems. More widely used for the company.


MICROSOFT WINDOWS
Is the most popular operating system. Almost everyone wore them. Some well-known version of Microsoft Windows: Microsoft Windows 98, 2000, Me, XP, Vista, and the most recent Windows 7.


APPLES Macintosh
Operating system is superior in terms of graphics. Requires special hardware that can not be installed in ordinary computer. Version include Mac OS X (Tiger), Leopard.

SOLARIS
Developed by Sun Microsystems. More widely used for the company.

Programming System

What is the difference in system program with other programs.

Systems Program: Programs that assist in effectively executing the "general user's" computing to meet the needs of a computer system.

The system helps the executable program "general user program" is effective on the computer system

Effektifitasnya include:

A. Effektifitas use of computer systems (the influence of computer system configurations: main storage, Auxiliaries, etc.)

2. Effektifitas human resources development program (the environmental impact of computing: program development, data processing, real time application, etc.)

Effektifitas (and efficiency) → Cost Optimization

"General User's" computing: special programs used by the user such as application software

Execution, including text input program, different levels of processing computer system (naming, storage, translation, Relocation, Linking, etc.)

What is the difference in system programming and other programming

Programming System: activities of designing and implementing systems

Language Translator

Originally created in the machine language program

Languange translator needs of language easily understood by kodeyang dipahamiprogrammer forms the engine

translator for the low-level programming language (assembly language): assembler

Languange Assembly has treated similar to machine language, such as the use of mnemonic opcode (LOAD, ADD, etc.), symbolic operand (VALUE, RESULT, etc.) and ease of modification to the program remains dependent on the machine used (machine dependent)

High level language that includes machine independent, Languange mempermudahprogrammer and already have a translator that can reduce design, coding and debugging program

Berners Lee

Berbagai temuan aplikasi untuk media digital yang menyertainya kemudian, WWW memang tidak perlu di tulis. Aplikasi Facebook atau Twitter untuk iPad, misalnya tidak perlu lagi menulis lagi “WWW” karena secara otomatis sudah membuka alamat itu dengan sendirinya. Karena berkembangnya aplikasi untuk berbagai media baru itulah, editor Wired, Chris Anderson,pernah menyatakan “the web is dead”. Menurut penulis buku laris Long Tail  ini, WWW ( yang ditemukan Berners Lee) menuju senja kala atau akhir dari kematiannya. Tentu saja ini hanya perkiraan Anderson semata. Toh hadirnya mesin cetak Gutenberg tidak pernah mematikan komunikasi lisan,kehadiran radio dan televise tidak mematikan komunikasi tulisan di Koran. kehadiran Online tidak juga mematikan media-media sebelumnya. Sekarang maraknya aplikasi dan bertumbuhnya para developer sehingga nokia sebagai produsen ponsel dunia perlu menyelenggarakan

“Developer Summit”, juga tidak akan mematikan online atau WWW melalui internet.

Dalam pemaparannya di nokia world 2010 itu, Berners Lee justru banyak memberikan banyak masukan kepada para pengembang peranti lunak (developer software), khusus berbagai aplikasi untuk ponsel pintar ini. Ia tidak menunjukan kekhawatiran akan ramalan segera matinya web, sebagai mana yang di kemukakan Anderson. ia justru memberikan solusi bermanfaat bagi para pengembang yang hadir pada forum itu.

Menurut Beners Lee para developers harus segera membuat aplikasi yang tepatuntuk berbagai media yang beragam. Para pengembang, menurut dia tidak boleh terpaku pada aplikasi “kuno” untuk desktop atau PC semata Karena media berinternet dengan bentuk lain,seperti iPad dan smartphone yang lebih mobile merupakan tantangan baru.

Berkat WWW yang ditemukannya, pada tahun 2004 Berners Lee di anugrahi Millenium Technologi Prize oleh pemertintah Finlandia dan berhak atas hadiah uang 1 juta euro (Rp.15 Milyar) yang diserahkan Presiden Tarja Halonen.pada tahun yang sama ia di anugrahi gelar “Sir” oleh Ratu Elizabeth II. Sejumlah gelar doctor honoris causa juga dia dapat dari berbagai universitas ternama dunia.

Narasumber : Kompas

Weaknesses Android

Android could be regarded as a new star in the world of mobile operating systems. Because of its popularity that shot, it's no wonder many advantages touted endlessly. However, like other OS, Android but has the advantage of a flaw.

Fragmentation. One word is mentioned practitioner Sebastian Lucky gadget weakness green robot OS. That is, not all devices can equally enjoy the superior features of Android.

"Of the many Android devices, from the cheapest to the millions of prices, which distinguishes what the heck? Feature. Example camera, Internet connection, the touch screen. So it was not able to walk all the excellent features on all Android devices," said Lucky.

The variety that carries a selection of Android devices is making his popularity soared, so familiar to many people. On the other hand, this might impact on different features in each device.

In the above series phones, all features will almost certainly be the way. In contrast to lower-middle-series phones, there's usually a number of features that are sacrificed.

"So its the same OS, but on the phone that one can walk (its), the other can not. Because there are too many kinds of Android devices," explained the father of sons.

But according to him, as a whole may be spelled a variety of features can be equally superior way in a variety of devices. Only decisive is about comfort.

"If the good games that need high processor for example. At low processor device may not work or was not optimal. So when he speaks to what must be repaired, it is difficult because it involves the hardware must always be a difference. Although the difference was more and more narrowed, "he said.

Fragmentation also makes each series according to which the latest Android OS is not directly adapted to all devices. Android developments are fast enough, the update could come twice a year, does not mean that all devices directly using the update.

"Mobile phones are not cheap to enjoy the latest OS. Sometimes there is a cheap phone that has long been out had no updates. As such, Android and more variety in terms of both hardware and OS. Android Ice Cream Sandwich only 7.1 percent of new gadgets that use," lid.

Sumber : Detik.com

The secret of the popularity of android

Several years ago, many people are still unfamiliar with Android. But now, slowly his popularity shot. This also happens in Indonesia, where it says smartphone users increasingly interested in using the device with the green robot OS. What's the secret?

In addition to the OS that are not paid, the diversity of the availability of gadgets to choose from, say practitioners gadget Android Lucky Sebastian is a privilege that a charm.

"Maybe because he's everywhere. If other platforms it's limited. For example, if we are talking about a BlackBerry, then there is no other brand, people would buy a BlackBerry. IPhone, too, and it is expensive, so reaching a bit," he explained.

According to him, this feature provides many options to make people free to buy the hardware they like. From the famous to the ordinary.

"People love the Samsung there, there HTC, LG, and even want to brand the middle of nowhere there is also the term. This is what makes Android exist everywhere, people would know," said the man from Bandung.

He added again, when people talk about the smartphone that occurred first is about the price is expensive. Well, variety selection of Android devices are expensive to cheap, to cover the problem.

"There's Android could buy several hundred thousand. And when compared to the feature phone, its really far. Although cheap, for example somehow easier for internet connection, and also many interesting applications," he explained.

The same thing happens also in the Android tablet. Indeed, no denying that the Android tablet is quite expensive, the specification is more convenient to use. But now it is starting a lot of cheap Android tablet whose specification includes good enough.

"The first time Android tablet era begins its components have not been many, so mass production is still constrained. Then turn so fast the processor finally makes a fairly capable processor time now cheaper. So now people have started thinkers even cheaper still better specifications, "said Lucky.

With a variety of options, there are mentioned Lucky affect the appearance of two camps. The first, consumers who have always wanted a nice device with a known brand, because they have the ability to buy it. Secondly, people who do their purchasing power is not too great, but it is technology literate.

Sumber : Detik.com

Transistor Sebagai Saklar

Berdasarkan karakteristiknya, selain sebagai penguat, transistor juga dapat berfungsi sebagai saklar. Apabila rangakaian transistor sebagai saklar menggunakan jenis transistor NPN, maka ketika basis diberi tegangan tertentu, transistor akan berada dalam kondisi ON (Saturasi), besarnya tegangan pada basis tergantung dari spesifikasi transistor itu sendiri (β, Vcc, dan IC Max).

         Terminal Basis akan mengontrol arus yang mengalir dari Collector ke Emitor. Arus atau tegangan tertentu yang dihubungkan ke input (terminal Basis) akan menyebabkan transitor saturasi seperti halnya saklar tertutup seolah-olah terminal Collector dan Emitor terhubung singkat seperti saklar tertutup, akibatnya arus akan mengalir dari Collector ke Emitor. Pada kondisi ini tegangan Collector-Emitor (V_ce) mendekati nol (0 Volt). Sebaliknya jika tidak terminal Basis tidak diberi arus atau tegangan, maka transistor akan berada dalam kondisi Cut-Off dan terminal Collector-Emitor terputus seolah saklar terbuka, akibatnya arus tidak akan mengalir dari Collector ke Emitor. Dalam kondisi ini tegangan Collector-Emitor akan maksimal (sama dengan Vcc).

              Sebuah transistor NPN mempunyai penguatan (β) 100 kali dan I_c = 20mA. Jika tegangan Vcc = 5 Volt, maka R_b (Resistor pada Basis) yang dibutuhkan untuk menghasilkan arus Basis agar transitor menjadi ON adalah:

 

Diketahui :

        I_c       =  20 mA = 0,02 A

        β     =  100

       V_be  = 0,6 - 0,7 Volt (Tegangan Basis-Emitor).Tegangan ini nilainya tetap.

        Vin  = 5 Volt

Ditanyakan :

Nilai R_b ?

Jawab :

  β     =  Ic/Ib

 100  =  20/Ib

  I_b    =  0,02/100

   I_b    =  0,0002 A (0,2 mA)

=>       R_b =  (Vin - Vbe)/Ib

                 =  (5 - 0,6)/0,0002

                 =  4,4/0,0002

                  =  22000 Ohm

                  =  22 KOhm 

        Pada gambar di atas, lampu L1 akan menyala jika Basis diberi tegangan 5 Volt dan akan padam ketika Basis (Vin)= 0 Volt. Pada saat L1 On, transistor bekerja seperti saklar tertutup dan ketika L1 Off, transistor bekerja seperti saklar terbuka. Transistor sebagai saklar ini menjadi cikal-bakal pembuatan IC Digital logika (logic gate).