Scada

SCADA is an acronym that stands for Supervisory Control and Data Acquisition. SCADA refers to a system that collects data from various sensors at a factory, plant or in other remote locations and then sends this data to a central computer which then manages and controls the data.
SCADA is a term that is used broadly to portray control and management solutions in a wide range of industries. Some of the industries where SCADA is used are Water Management Systems, Electric Power, Traffic Signals, Mass Transit Systems, Environmental Control Systems, and Manufacturing Systems.

SCADA as a System

There are many parts of a working SCADA system. A SCADA system usually includes signal hardware (input and output), controllers, networks, user interface (HMI), communications equipment and software. All together, the term SCADA refers to the entire central system. The central system usually monitors data from various sensors that are either in close proximity or off site (sometimes miles away).
For the most part, the brains of a SCADA system are performed by the Remote Terminal Units (sometimes referred to as the RTU). The Remote Terminal Units consists of a programmable logic converter. The RTU are usually set to specific requirements, however, most RTU allow human intervention, for instance, in a factory setting, the RTU might control the setting of a conveyer belt, and the speed can be changed or overridden at any time by human intervention. In addition, any changes or errors are usually automatically logged for and/or displayed. Most often, a SCADA system will monitor and make slight changes to function optimally; SCADA systems are considered closed loop systems and run with relatively little human intervention.
One of key processes of SCADA is the ability to monitor an entire system in real time. This is facilitated by data acquisitions including meter reading, checking statuses of sensors, etc that are communicated at regular intervals depending on the system. Besides the data being used by the RTU, it is also displayed to a human that is able to interface with the system to override settings or make changes when necessary.
SCADA can be seen as a system with many data elements called points. Usually each point is a monitor or sensor. Usually points can be either hard or soft. A hard data point can be an actual monitor; a soft point can be seen as an application or software calculation. Data elements from hard and soft points are usually always recorded and logged to create a time stamp or history

User Interface (HMI)

A SCADA system includes a user interface, usually called Human Machine Interface (HMI). The HMI of a SCADA system is where data is processed and presented to be viewed and monitored by a human operator. This interface usually includes controls where the individual can interface with the SCADA system.
HMI's are an easy way to standardize the facilitation of monitoring multiple RTU's or PLC's (programmable logic controllers). Usually RTU's or PLC's will run a pre programmed process, but monitoring each of them individually can be difficult, usually because they are spread out over the system. Because RTU's and PLC's historically had no standardized method to display or present data to an operator, the SCADA system communicates with PLC's throughout the system network and processes information that is easily disseminated by the HMI.
HMI's can also be linked to a database, which can use data gathered from PLC's or RTU's to provide graphs on trends, logistic info, schematics for a specific sensor or machine or even make troubleshooting guides accessible. In the last decade, practically all SCADA systems include an integrated HMI and PLC device making it extremely easy to run and monitor a SCADA system.

SCADA Software and Hardware Components

SCADA systems are an extremely advantageous way to run and monitor processes. They are great for small applications such as climate control or can be effectively used in large applications such as monitoring and controlling a chemical plant or mass transit system.
SCADA can come in open and non proprietary protocols. Smaller systems are extremely affordable and can either be purchased as a complete system or can be mixed and matched with specific components. Large systems can also be created with off the shelf components. SCADA system software can also be easily configured for almost any application, removing the need for custom made or intensive software development.

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Video surveillance system

Video surveillance system refers to a video device that enables continuous or periodic video recording, observing of personal information about individuals in open public spaces (Ann Cavoukian, 2007). Video surveillance began in the 1960’s when closed-circuit television was first used to monitor and record activities at remote locations. Right now, digital camera and wireless network will support video surveillance to become more extensive, effective and feasible. Look : http://ft.unand.ac.id

Development in computing technology, compression technique and high speed networks have made demand for Internet video streaming service grown rapidly over past few years. It to be a challenging task to make video streaming system with high quality that can adapt to unpredictable channel characteristic, device capability and user preferences. It is not surprising that these challenges, in conjunction with the commercial promise of the technology, has attracted considerable research efforts, particularly directed towards efficient, robust, scalable and low-latency video coding and transmission (M. R. Civanlar et al., 2001, C. W. Chen et al., 2001).

There are six areas closely related and they are coherent constituents of video streaming architecture (Dapeng Wu, 2001), as we can see in figure 1.

Figure 1. Architecture of Video Streaming

From this paper, writers describe six areas and give readers a perspective on the range of options available, and the associated tradeoffs among performance, functionality, and complexity. In efforts, researchers study part of this area and make several techniques in order to gain high quality video streaming system.

There is a Fine-Granular-Scalability (FGS) framework that strikes good balance between coding efficiency and scalability while maintaining a very flexible and simple video coding structure (Hayder M. Radha et al., 2001). FGS has been recently adopted by the ISO MPEG-4 video standard as the core video-coding method for MPEG-4 streaming applications. At paper titled “Error Control and Concealment for Video Communication --- A Review” Yao Wang and Qin-Fa Zhu summarize and critique the approaches that have been developed for error control and concealment. And one of technique for coding manipulation there is Leaky Prediction (Sangeun Han and Bernd Girod, 2002) that suitable for time-varying error-prone channels, such as internet or wireless channel.

In wireless communication application, this multimedia data will be stream over various conditions. There are divergences in access networks, device, resource capability, bandwidth variation, networks condition and access by large number user anytime and from anywhere. This networking paradigm is often referred to as Universal Multimedia Access (UMA) (Mihaela van der Schaar and Hayder Radha, 2001). Therefore, video streaming applications need to implement highly scalable and adaptive techniques. The application need to modify content encoding and transmission rates in order to cope with the erroneous and time variant conditions of the network. One of it is Fuzzy Rate Control (Pavlos Antoniou et al., 2007) which proposed to adaptive feed back algorithm for internet video streaming.