• Journal of the Korea Convergence Society
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• v.2 no.1
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• pp.7-13
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• 2011

Informations of multimedia centering in the images, are combined acoustic and letter, etc. Although the network advances and the capacity of the storage media extends, these huge informations will not be able to accommodate. From meaning which is like this, International standards for the compression and a multiplexing of image, acoustic and voice H261 where admits standard, JPEG, JBIG, MPEG-l, MPEG-2, MPEG-4 and H263, G series etc, are core techniques of multimedia. At initial step of the base technique which creates the base of like this multimedia service time, we developed the real-time MPEG-4 transmission systems to provides real-time MPEG-4 multimedia services. This system means becomes the base technique which hereafter is developed and is applied various system. This system Will be able to apply from a videoconference, a building protection system and a VOD video system to use the Internet. And, They, the image sensing, embedded linux, and MPEG4 software, will become sourceful technique to develop the different system.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2003.10a
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• pp.129-132
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• 2003

In this paper, which sees the Strong-ARM SA1110 it used the main CPU and RTP in VoIP system. It will be able to apply the information communication field it embodied. It used the Tynux_box2 with the hardware side and it composed a VOIP system. And it used the RTP which is a real-time protocol in software control portion. The development environment of the paper that used the Target board and a Linux PC for connection used the RS-232C, USB connection, Ethernet LAN. The VoIP the environment for a communication used the wave file in the substitution which changes analog signal with the digital signal. And For the communication of the both sides it used the socket. This paper explained the fact that against a general technique from the operation of VoIP system. Using the Embedded linux development board which explained an operational process of the RTP protocol.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.26 no.1
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• pp.1-6
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• 2022

Recently, IoT sensors are often used to produce stream data locally and they are provided for edge computing applications. Mass-produced data are stored in the mobile device's database for real-time processing and then synchronized with the server when needed. Many mobile databases are developed to support those applications. They are CloudScape, DB2 Everyplace, ASA, PointBase Mobile, etc, and the most widely used database is SQLite3 on Linux. In this paper, we focused on the performance required for synchronization with the server. The search performance required to retrieve SQLite3 was compared and analyzed according to the type of each Linux file system in which the database is stored. Thus, performance differences were checked for each file system according to various search query types, and criteria for applying the more appropriate Linux file system according to the index use environment and table scan environment were prepared and presented.

• Journal of Computing Science and Engineering
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• v.9 no.2
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• pp.108-117
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• 2015

Interrupt handling is generally separated from process scheduling. This can lead to a scheduling anomaly and priority inversion. The processor can interrupt a higher priority process that is currently executing, in order to handle a network packet reception interruption on behalf of its intended lower priority receiver process. We propose a new network interrupt handling scheme that combines interrupt handling with process scheduling and the priority of the process. The proposed scheme employs techniques to identify the intended receiver process of an incoming packet at an earlier phase. We implement a prototype system of the proposed scheme on Linux 2.6, and our experiment results show that the prototype system supports the predictable real-time behavior of higher priority processes even when excessive traffic is sent to lower priority processes.

• Proceedings of the KIEE Conference
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• 2005.05a
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• pp.188-190
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• 2005

In this study, a smart motor control and monitoring system is developed with an embedded board where Intel PXA255B CPU is mounted. Linux is ported into the embedded board as RTOS(Real Time Operating System), and the environment which communicate with a motor driver through serial protocol and is capable of controlling and monitoring the motor in real time is built in the system. A user friendly GUI is developed for the convenient operation of the system. Also, the environment which is able to control and monitor the motor driver remotely is built in the system using TCP/IP protocol.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.5 no.1
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• pp.60-64
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• 2004

In this paper, we implemented a real-time remote home monitoring system which we have ported the Linux OS and HTTP(Hypertext Transfer Protocol) web server. The GoAhead web server was ported using by ARM cross compiler. And then we used the analog to digital converter ADC0809 for sensing the vii able input signal at widely separated home. We have implemented linux device driver for ADC(Analog to Digital Convertor) and CGI-C(Common Gateway Interface - C language) application program using Client pull method for monitoring real-time changing data. The factor of monitoring is temperature, intensity of illumination and gas's existence. And this system has ability which check the status of out door and gas valve. We have designed the embedded web server system for home emergency monitoring in low cost.

• The KIPS Transactions:PartA
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• v.8A no.4
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• pp.311-318
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• 2001

In recent years, users\` demands for multimedia service are increasing because of a diffusion of internet. Server systems, however, offer inefficient multimedia data service to users. Multimedia applications often transfer the same data between shared devices at very high rates, and therefore require an efficient I/O subsystem. Data copying and context switching have long been identified as sources of I/O inefficiency. Therefore we propose the new Multimedia Stream System Call (MSSC) mechanism, which is inserted into a Linux kernel: The MSSC mechanism operates in kernel domain with RTP (Real-time Transport Protocol). We present measurements indicating that use of our techniques resulted in a 12.5%∼14% gain in throughput as compared with a conventional Linux system.

• Journal of Korea Society of Digital Industry and Information Management
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• v.10 no.2
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• pp.13-20
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• 2014

In this paper, we implemented the object scanning with nxtOSEK which is an open source platform. nxtOSEK consists of device driver of leJOS NXJ C/Assembly source code, TOPPERS/ATK(Automotive real time Kernel) and TOPPERS/JSP Real-Time Operating System source code that includes ARM7 specific porting part, and glue code make them work together. nxtOSEK can provide ANSI C by using GCC tool chain and C API and apply for real-time multi tasking features. We experimented the 3D scanning with ultra sonic and laser sensor which are made directly by laser module diode and experimented the measurement of scanning the object by knowing x, y, and z coordinates for every points that it scans. In this paper, the laser module is the dimension of $6{\times}10[mm]$ requiring 5volts/5[mW], and used the laser light of wavelength in the 650[nm] range. For detecting the object, we used the beacon detection algorithm and as the laser light swept the objects, the photodiode monitored the ambient light at interval of 10[ms] which is called a real time. We communicated the 3D scanning platform via bluetooth protocol with host platform and the results are displayed via DPlot graphic tool. And therefore we enhanced the functionality of the 3D scanner for identifying the image scanning with laser sensor modules compared to ultra sonic sensor.

• IEIE Transactions on Smart Processing and Computing
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• v.4 no.2
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• pp.65-70
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• 2015

In this paper, we describe the world's first real-time ray-tracing chip architecture. Ray-tracing technology generates high-quality 3D graphics images better than current rasterization technology by providing four essential light effects: shadow, reflection, refraction and transmission. The real-time ray-tracing chip named RayChip includes a real-time ray-tracing graphics processing unit and an accelerating tree-building unit. An ARM Ltd. central processing unit (CPU) and other peripherals are also included to support all processes of 3D graphics applications. Using the accelerating tree-building unit named RayTree to minimize the CPU load, the chip uses a low-end CPU and decreases both silicon area and power consumption. The evaluation results with RayChip show appropriate performance to support real-time ray tracing in high-definition (HD) resolution, while the rendered images are scaled to full HD resolution. The chip also integrates the Linux operating system and the familiar OpenGL for Embedded Systems application programming interface for easy application development.

• Journal of KIISE:Computer Systems and Theory
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• v.37 no.1
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• pp.35-42
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• 2010

Guest operating systems running over the virtual machines share a variety of resources. Since CPU is allocated in a time division manner it consequently leads them to having the unknown physical time. It is not regarded as a serious problem in the server virtualization fields. However, it becomes critical in embedded systems because it prevents guest OS from executing real time tasks when it does not occupy CPU. In this paper we propose a hypercall to register a timer service to notify the timer request related real time. It enables hypervisor to schedule a virtual machine which has real time tasks to execute, and allows guest OS to take CPU on time to support real time. The following experiment shows its implementation on Xen-Arm and para-virtualized Linux. We also analyze the real time performance with response time of test application and frames per second of Mplayer.