• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2007.11a
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• pp.253-256
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• 2007

The web server for the embedded Linux system(ELS), unlike the ones for the usual Linux or Windows, has some disadvantages such as small number of installable applications, low compatibility and limited extensibility. This fact raises some problems when data are transferred in real-time via the web server, which are mainly caused by a poor performance of the processor and small-sized memory. Conventional user interfaces adopted for the usual web servers are unsuitable for the ELS because they are platform-limited and their installations are done by the form of plug-ins. If the web server for the ELS has an Ajax engine that can be utilized without any installation procedure, the advantages of usability, accessibility and quick response time can be obtained. This paper presents the Ajax interface for the ELS web server. The efficiency of the proposed technology in the real-time remote monitoring is shown through an implementation.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.5 no.6
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• pp.1078-1082
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• 2001

This is an example of ABSTRACT format. We made a HTTP server using 8 bit microprocessor It was TMP84c015 which applied a z80 core and RTL8019AS was installed for an ethernet physical layer. Assembly language was used to optimized a performance of the MPU, to overcome an restriction of memory sire and to maximize the throughput of packet using TCP, UDP, IP, ICMP, ARP protocol. We used LabVIEW to verify the each protocol on the client side.

• Journal of the Korean Institute of Telematics and Electronics C
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• v.35C no.2
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• pp.36-47
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• 1998

Low power circuit techniques have been developed to realize the highest possible performance of embedded SRAM at 1V power supply with$0.5\mu\textrm{m}$ single threshold CMOS technology in which the unbalance between NMOS and PMOS threshold voltages is utilized to optimize the low power CMOS IC design. To achieve the best trade-off between the transistor drivability and the subthreshold current increase, the ground potential of memory array is raised to suppressthe subthreshold current. The problems of lower cellstability and bit-line dealy increase due to the enhanced array ground potential are evaluated to be controlled within the allowable range by careful circuit design. 160MHz, 128kb embedded SRAM with 3.4ns access time is demonstrated with the power consumption of 14.8mW in active $21.4{mu}W$ in standby mode at 1V power supply.

• IEMEK Journal of Embedded Systems and Applications
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• v.5 no.4
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• pp.175-184
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• 2010

This paper designs a virtual USB drive for mobile devices which gives an illusion of a traditional USB flash memory drive and provides capacity-free storage space over IP network. The virtual USB drive operating with a S3C2410 hardware platform and embedded linux consists of USB device driver, an iSCSI-enabled network stack, and a seamless USB/iSCSI tunneling module. For performance enhancement, it additionally provides a kernel-level seamless USB/iSCSI tunneling module and data sharing with symbol references among kernel modules. Experiments reveal that the kernel-level implementation can improve the I/O performance up to 8 percentage, as compared with the user-level implementation.

• IEMEK Journal of Embedded Systems and Applications
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• v.8 no.3
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• pp.145-153
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• 2013

Virtualization technology has been applied in IA-32 based server or desktop systems. Recently it has been applied in ARM based mobile systems. Virtualization technology provides many useful features that are not possible in operating system level such as isolation, interposition, encapsulation and portability. In this research, we implement an ARM based VMM(Virtual Machine Monitor) by using the following techniques. First, we use "emulation" to virtualize the processor. Second, we use "shadow page tables" to virtualize the memory. Finally, we use a simple "pass-through I/O" to virtualize the device. Currently the VMM runs ARM Linux kernel 3.4.4 on a BeagleBoard-xM, and we evaluated the performance of the VMM using lmbench and dhrystone. The result of the evaluation shows that our VMM is slower than Xen on ARM that is implemented using paravirtualization but has good performance among the VMMs using full-virtualization.

• IEMEK Journal of Embedded Systems and Applications
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• v.8 no.3
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• pp.179-184
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• 2013

A voice recognition technology as a technology fundament plays an important role in medical devices with smart functions. This paper describes the implementation of a control system that can be utilized as a part of illumination equipment for medical applications (IEMA) based on a voice recognition. The control system can essentially be divided into five parts, the microphone, training part, recognition part, memory part, and control part. The system was implemented using the RSC-4x evaluation board which is included the micro-controller for voice recognition. To investigate the usefulness of the implemented control system, the experiments of the recognition rate was carried out according to the input distance for voice recognition. As a result, the recognition rate of the control system was more than 95% within a distance between 0.5 and 2m. The result verified that the implemented control system performs well as the smart control system based for an IEMA.

• Journal of Sensor Science and Technology
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• v.21 no.1
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• pp.21-27
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• 2012

In this study, we designed an embedded system for automatic condensation control(ESCC) of the car. This system heats the car glasses as and when it is needed that makes driving safer and convenient. The system was built on an ATmega128L central processing unit(CPU), using high-performance electrically erasable programmable read-only memory(EEPROM) complex programmable logic device(CPLD) ATF1504AS, using which an ESCC algorithm has been proposed. The source code was written in C language. The algorithm of work was written using the dew-point table. This system not only clears the condensation on the glass but also averts condensation. The designed ESCC system begins working once the input information comes close to the dew-point table information. This device enables a wider field of view, thereby increasing safety.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.51 no.4
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• pp.198-205
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• 2002

In this paper, we proposed a wavelet image coder based on the portable embedded microprocessor. The proposed coder stores the bit level information of the wavelet coefficient in the 2D significance array. Using this information, the coder make the significance check for coefficient and bit level scanning at the same pass. The proposed method has the advantage that we can reduce the scan iteratively and the memory usage for the coding process. Experimental results show that the proposed method outperforms popular image coders such as JPEG, EZW and SPIHT in based on the portable embedded system environment.

• Journal of Information Processing Systems
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• v.13 no.1
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• pp.26-39
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• 2017

The need for embedded devices to be able to exchange information with each other and with data centers is essential for the advent of the Internet of Things (IoT). Several existing communication protocols are designed for small devices including the message-queue telemetry transport (MQTT) protocol or the constrained application protocol (CoAP). However, most of the existing implementations are convenient for computers or smart phones but do not consider the strict constraints and limitations with regard resource usage, portability and configuration. In this paper, we report on an industrial research and development project which focuses on the design, implementation, testing and deployment of a MQTT module. The goal of this project is to develop this module for platforms having minimal RAM, flash code memory and processing power. This software module should be fully compliant with the MQTT protocol specification, portable, and inter-operable with other software stacks. In this paper, we present our approach based on abstraction layers to the design of the MQTT module and we discuss the compliance of the implementation with the requirements set including the MISRA static analysis requirements.

• Proceedings of the KIEE Conference
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• 2003.11c
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• pp.932-936
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• 2003

AVLS is nowadays pretty considered on one of important parts in telematics service with a computerization of vehicle. However, with an implementation of commercial OS, individual OS and firmware on AVLS terminals, the cost and developing period are significantly increased. In this paper, we present the effective log-file creation methode about automobile status and location information within a restricted memory through designing AVLS terminals based on embedded linux. The proposed method shows 0.8% better performance on bzip2 compressor comparing to gzip compressor in the compressibility. In addition, bzip2 is faster than gzip about 2.14 times in the speed of compression.