we are a group of student from University Technology Malaysia who are doing our group blog. Hope all the information and videos can help you understand well about technology information.
•An acronym for Redundant Array of Independent Disks • Technology that provides increased storage functions and reliability through redundancy • This is achieved by combining multiple disk drive component into a logical unit, where data is distributed across the drives in one of several ways called “RAID levels” • RAID is now used as an umbrella term for computer data storage schemes that can divide and replicate data among multiple disk drives • The schemes or architectures are named by the word RAID followed by a number (e.g. RAID 0, RAID 1) • The various designs of RAID systems involve 2 key goals: increase data reliability and increase input/output performance • When multiple physical disks are set up to use RAID technology, they are said to be in a RAID array • This array distributes data across multiple disks, but the array is addressed by the operating system as one single disk • RAID can be set up to serve several different purpose
·Capture images from photographic prints, posters, magazine pages, and similar sources for computer editing and display
·Come in hand-held, feed-in, and flatbed types
·For scanning black-and-white only, or color.
·Very high resolution scanners are used for scanning for high-resolution printing
·Lower resolution scanners are adequate for capturing images for computer display
·Scanners usually come with software, such as Adobe’s Photoshop product, that lets us resize and otherwise modify a captured image
·Usually attach to our personal computer with a Small Computer System Interface (SCSI)
·An application such as Photoshop uses the TWAIN program to read in the image
·Some major manufacturers of scanners include: Epson, Hewlett-Packard, Microtek, and Relisys
TWAIN
§Widely-used program that lets we scan an image (using a scanner) directly into the application (such as Photoshop)
§Without TWAIN, would have to close an application that was open, open a special application to receive the image, and then move the image to the application where you wanted to work it
§TWAIN driver runs between an application and the scanner hardware
§TWAIN usually come as part of the software package we get when we buy a scanner
§It also integrated into Photoshop and similar image manipulation programs
Network attached storage (NAS) versus Storage area network (SAN).
Data is importance and there is variety of data in this world. Therefore a secondary storage which is permanent and non- volatile is necessary as a component to store the data in this globalization era.
The NAS and SAN is a newer and more advance storage if compare to other secondary storage such as floppy disc and hard disc.
The NAS and SAN are capable to store large amount of data so there often been use by organization rather than individual.
Network attached storage (NAS) and Storage area network (SAN) always been see as an identical storage, somehow they still have difference although they are almost identical.
Therefore when we want to apply or use NAS and SAN, we need to choose carefully because they may not suitable for certain condition.
For example, NAS was File-level data sharing across the enterprise. Therefore NAS is more suitable to the condition which needs to address the challenges inherent in a server- based infrastructure such as direct-attached storage.
While SAN has the high availability for block-level data transfer. Therefore is is suitable to transfers data between servers and storage devices, separate from the local area network.
- NAS devices are connected to a local area network (LAN) through the network router or a network switch. Typically, Ethernet cables are used for the connection in the same way that computers on the network are connected.
- SAN devices connect to a number of servers using fiber channel. Most SAN systems use the small computer system interface protocol. An add-on card must be installed in each computer that will be connected to a SAN device.
- Any computer on the network can see a connected NAS device, and each computer recognizes it as a shared, external storage drive. Because the NAS system hides machine-dependent, low-level data management, files on a NAS device can be shared with most operating systems simultaneously.
- SAN is seen by a connected server as a local drive. Since the SAN serves data only as raw disk blocks, the server itself must provide file management.
4. Uses for Each
- NAS device can make files available to any computer on a network. Additional NAS devices can be added to the network to expand storage space, and the devices can work together to appear as a single, shared network drive.
- SAN provides storage space that can be shifted from one serverto the next as the needs of each server change. Any capacity not being used by one server can simply be allotted to another.
5. Off-Site Storage
- NAS devices can be exposed on a wide area network such as the internet, making it possible to install a NAS system anywhere outside a home or office while still having shared access to its files.
- According to the NAS-SAN website, the fiber channel used in a SAN has a maximum distance of 10 km. While this can provide shared storage between nearby offices and protection against some disasters, it limits the available locations where a SAN may be placed.
- NAS and SAN might seem almost identical
- Both NAS and SAN generally use RAID connected to a network, which then are backed up onto tape.
- There still have differences, important differences which can seriously affect the way your data is utilized.
- For a quick introduction to the technology, take a look at the diagrams below.
More Differences
NAS
SAN
Almost any machine that can connect to the LAN (or is interconnected to the LAN through a WAN) can use NFS, CIFS or HTTP protocol to connect to a NAS and share files.
Only server class devices with SCSI Fibre Channel can connect to the SAN. The Fibre Channel of the SAN has a limit of around 10km at best
A NAS identifies data by file name and byte offsets, transfers file data or file meta-data (file's owner, permissions, creation data, etc.), and handles security, user authentication, file locking
A SAN addresses data by disk block number and transfers raw disk blocks.
A NAS allows greater sharing of information especially between disparate operating systems such as Unix and NT.
File Sharing is operating system dependent and does not exist in many operating systems.
File System managed by NAS head unit
File System managed by servers
Backups and mirrors (utilizing features like NetApp's Snapshots) are done on files, not blocks, for a savings in bandwidth and time. A Snapshot can be tiny compared to its source volume.
Backups and mirrors require a block by block copy, even if blocks are empty. A mirror machine must be equal to or greater in capacity compared to the source volume.
Here is a video on NAS VS SAN , have a look =)
References from
1.Computing Essentials Complete 2010 by Timothy J.O'Leary and Linda I.O'Leary from McGRAW Hill
- From French company JazzMutant which serves as a controller for musical devices such as synthesizers and mixing consoles as well as for other media applications such as video performances.
- Creating an Interface
= Comes with its own proprietary software called the JazzEditor to create interfaces.
= Users canbuild interfaces using a selection of 15 different objects (including fader, knobs, pads and sliders), group them as modules and arrange them using as many pages as needed.
= Each object can then receive any MIDI or OSC attribute.
= Particularity is the ability tomodify the physical behavior of each object (for instance adding or removing friction on faders).
= The internal memory of the Lemur enables the storage of many interfaces, each one controlling a specific software for instance.
- Role is equivalent to that of a MIDI controller in a MIDI studio setup, except that the Lemur uses the Open Sound Control (OSC) protocol, a high-speed networking replacement for MIDI.
- Low latency, higher data capacity, 32-bit numerical precision and easy set-up if compare to MIDI.
- Supported by an emerging number of applications, this protocol opens a new era in the field of real-time control and human-machine interfaces.
- A controller that thinks ahead and is able to adapt with the ever-changing landscape.
- The controller is especially well-suited for use with Reaktor and Max/MSP, tools for building custom software synthesizers.
- Enhance that precision, by zooming-in on any control.
- To save and navigate through all your interfaces with the touch of a button
- Can tweak the 32 bands of a vocoder, control the most complex polyphonic granular synthesizer, or even generate crazy rhythmic patterns with the MultiSlider.
- Integrate your lemur in a fast network
= Connectnumerous computers and Lemurs on a local area network and make them all dance together.
= Faster data flow means seamless communication.
= The Lemur's fast Ethernet interface ensures a data flow hundreds of times faster than your average MIDI interface.
= The Lemur has a built in 100BaseT interface, which means that the Lemur is capable of exchanging thousands of control messages at once with your application.
- Complete the Picture
= JazzDaemon is a background application running on your host computer that handles MIDI communication between the Lemur and any number of MIDI applications or devices connected to your host computer.
= This single interface allows you to control the track levels of your sequencer with one hand while playing your hardware sampler or virtual instrument with the other. Multi-tasking at its finest!
= Enhanced control of all your envelopes with the new Breakpoint object - Allows you to see exactly how you are changing the sound and you can easily add extra breakpoints with a simple double touch by offers total control of synthesizer or sampler envelopes with a multi-segment envelope editor.
= Faster set-up with the Alias feature - Duplicate a controller object that sends exactly the same information to your computer as the original with Alias.
= Mouse and keyboard control - Lemur's objects can be used to remotely control the mouse cursor or computer keyboard.
= Acute precision with the new Gesture object - Emulates a track pad control with advanced gesture recognition and has three novel ways to interact with your sound. Pinch, rotate or trace your fingers to send different control messages to your computer.
= Extended scripting abilities - In the JazzEditor, a new Multiline script pane opens up a whole new world of possibilities. Any changes in your Live set are automatically reflected on the Lemur.
Here is a video that show on Lemur Input Device =)
Manipulate buttons and knobs for some tasks or programs by using mouse nowadays are very troublesome and inconvenient. Somehow with the technology, there are many innovation that let us input conveniently such as multi touch by surface interface. The innovation of surface interface can be act as an input device which allows us to interact directly with the surface that we touch.
The Lemur input device is a hardware controller which applies the innovation of surface interface. It is a new development in music technology. By having Lemur input device as a control surface in live performance feels much more like playing an actual instrument than simple turning knobs or moving sliders. The Lemur also offers new method to communicate with the digital musical instruments which are not comprehended in physical hardware and allow for new creative possibilities.
References from
1. Computing Essentials Complete 2010 by Timothy J.O'Leary and Linda I.O'Leary from McGRAW Hill
Since our lecturer wants us to explore something does not discuss deeply in the blog, and she give us some ideas about the topic we can discuss. So, i would like to choose the topic' how does the touch-screen works? ' This is because i am interested in this topic and i got the experience to use the iPhone. I found that if i use my fingernail to touch the screen, i could not get the sensor. I need to use my fingertip to touch the sceen just can get the sensor.
Why You Can Only Touch With Your Finger
Most other touch screen devices allow the use of a stylus, or at least the touch screen can function when you touch it with something besides your finger. But with the iPhone, you have to touch the screen with your finger. This is because the iPhone can have a capacitor at every point on the screen only because each capacitor relies on feedback from the electricity in your finger to operate. When you touch the screen, the screen at that point senses the natural capacitance of your body (your body's ability to hold an electrical charge) and then registers a change in current at that point on the screen. If you use a stylus to touch the iPhone's screen or touch it with a gloved hand, the iPhone will not be able to pick up any natural capacitance and so it won't know you're touching it there.In reality, the iPhone has one half of a capacitor at every pointon the screen. The other half of the capacitor is your finger. Together, the circuit beneath the glass cover and the capacitance in your finger change the electrical charge at that point on the screen.
I would like to discover more about the multi-touch in iPhone.
Each position on the iPhone's screen can independently pick up a touch. This means that you can touch the screen in more than one place at a time, and the iPhone will register all touches. Apple used this multi-touch feature in many of the applications and software on the phone. For example, when you are using a maps application or browsing your pictures on the phone, you can make a pinching motion on the surface of the screen and that gesture will zoom the image out. If you want to zoom in, you start with your fingers together on the screen's surface and then pull your fingers apart and watch as the application zooms in on where you first touched the screen.
If you want to know more about the topic, you may search from the web.
Since i found that the function oftouch-screen in iPhone and iPod are almost similar, so i would also like to share about the infomation i found from Internet.
When you touch the screen, the iPod's circuitry detects the presence of your finger. It keeps track of how many fingers you have on the screen and where you move them. It also gives the iPod touch the capability of running apps. The iPod touch does this using a layer of capacitive material under a protective covering. You can read How Capacitors Work to learn more about them, but the basic idea involves taking advantage of the electrical properties of the human body. When you touch a capacitive surface, the amount of charge it holds changes. This is why devices like the iPod touch require you to touch them with your bare skin -- insulating materials like gloves, pens and styluses don't cause the same changes in the capacitive circuitry.
The basic process behind detecting touch
There are two possible methods the iPod touch can use to measurechanges in electrical states:
Self capacitance: Circuitry monitors changes in an array of electrodes.
Mutual capacitance: A layer of driving lines carries current. A separate layer of sensing lines detects changes in the electrical charge when you place your finger on the screen.
Regardless of which method the screen uses, you change the electrical properties of the screen every time you touch it. The iPod records this change as data, and it uses mathematical algorithms to translate the data into an understanding of where your fingers are.
Why does ipad touch-screen work with fingernails but droid does not?
Both the iPad and Droid use capacitive touch screens, which work by sensing the disruption of the electric field at the surface of the screen by a conductive object (i.e. your finger). Neither of them should really work with a fingernail, as the nail isn't really conductive - I would guess that the reason the iPad picks up input from your fingernail is because its screen is more sensitive (probably because it is much larger), and therefore just having your finger near the screen (at a fingernail-length distance away) is enough to register without actually needing you to contact the surface.
