Earticle

LED communication is a communication technology to transmit data using visible light coming out from the light emitting diode(LED). It is a technique that can overcome radio frequency(RF) communication problem that is an interference between electronic devices. As a technique that can be used as lighting and communications with using LED, LED communication systems are suitable for ubiquitous environment. This paper introduces the process of data transmission algorithm for LED-ID systems algorithm using LED, photodiode(PD), and micro controller unit(MCU) and analyzes the performance of the algorithm.

In this paper, we proposed the software architecture for a data collection unit using a Modbus communication protocol. This architecture consists of three blocks - XML parsing block, database block for storing monitoring data and its meta-data and Modbus communication block. XML parsing block makes meta-data of device's memory map from xml files. After parsing the file, there are two tables for storing meta-data and monitoring data table in the database. When the data collecting unit starts to communicate with devices, Modbus communication block builds the meta-data of the device's memory map from meta-data table. With this meta-data, communication block reads the monitoring data from devices. After that, data converting module converts the data using meta-data then stores the converted data to database. So, an operator wants to add heterogeneous devices in the monitoring system, just inserts the xml files to the data collection unit. By using the proposed system, it is possible to operate and maintain a system through concentrating on the development of the quality of the product itself.

Users are accustomed to upload their photos to the online image services due to the increasing popularity of the hand-held devices equipped with a camera. In such services, the image recognition service is a service that returns the information of the query image uploaded by an user. Before designing and implementing this image recognition system, just in case the size of the database increases, a system administrator need to consider a scalability problem. To solve a scalability problem, one can adopt the technology from conventional information retrieval. However direct adoption degrades image recognition system’s performance. In this paper, we analyse the factors affecting the performance on image recognition system using bag-of-visual-words which is derived from text retrieval.

In this paper, we analyzed various proposals to improve the technical regulation for telecommunication facilities in customer premises. In Article 3 of the technical regulation, Terms definition of installation box for CATV system and/or intergrated reception system is deleted, because it conflicts with Article 29. And Article 29 is revised to have more obvious meaning. In the revised Article 29, the office line have to interconnect with a cable in customer premises certainly, and if the office line is an optical fiber cable, telecommunication Surge Protective Device(SDP) is not necessary. In Article 30, we prepared more clear exceptive clause about installation of customer premises terminal box. The other issued proposals are under study to make more resonable and adequate amendments of the technical regulation. for telecommunication facilities in customer premises.

In this paper, we propose a simple OFDM (orthogonal frequency division multiplexing) frame synchronization scheme for high-speed LED communication systems. Frame synchronization is an essential procedure for normal operation of the OFDM systems on account of sensitivity to synchronization errors. In order to enhance the OFDM frame synchronization performance, we add a repeated orthogonal Gold sequence (ROGS) directly to OFDM signals in the time domain. The power level of a ROGS needs to be low enough in order not to affect a normal operation of the LED communication systems. Frame synchronization can be achieved successfully over optical channels interfered by impulsive noise owing to good auto-correlation properties of the ROGS.

This paper introduces an efficient Modbus communication topology for Electrical Energy Storage System. A communication topology is important to guarantee the performance of Electrical Energy Storage Systems. So, we had proposed a Programmable Logic Controller based Modbus communication topology and verified with 1-MW EES system. This paper summarizes implementation results of a proposed communication topology.

This study analyzes the effects of discretized control update times for a battery energy storage system (BESS) based on a digital controller. In the proposed model, the decentralized BESS selects a reasonable drooping coefficient (or proportioanl gain based on frequency) RB for the system frequency. This study uses two area models that represent a seven-bus system and two battery storages for frequency regulation.

Currently, GPS(Global Positioning System) is used to find user location information. However, in some cases, especially in urban environments, we receive unreliable location information due to multipath fading. In order to resolve this problem, we propose a closely coupled positioning technique where GPS signal is combined with QZSS signal. Also we proposed and analyze a combining algorithm of GNSS and Wi-Fi signals to get closely coupled location information by referring AP information. Finally, this paper proposes a combined GPS/QZSS/Wi-Fi navigation algorithm to improve navigation performance, and it is verified by car deriving test according to availability and accuracy standard.

In this paper, we captured theory that telecommunication lines received screening effect by underground utilities and proportional relationship between the underground utilities 's diameter and size of screening effect. Also we tried to predict based on the theory and proved it through collected data from the actual field measurement.

Software standards for Aerospace industry can be divided into airborne software standards and navigation safety facility software standards. Software standard for Airborne is DO-178B. It is used around the world and it is necessary in Korea. Software standard for non-airborne like navigation safety facility is DO-278A which is created on the basis of DO-178B. Because it has never applied to the software in Korea, it need research. In this paper, we analysis navigation safety facility software certification procedure using order FAA Order 8110.49 “Software Approval Guidelines” which explain certification procedure of DO-178B.

Ad-hoc networks employing cognitive radio(CR) system that guarantee high spectrum utilization provide effective way to increase the network capacity. However, there is a problem that all CR user do not fairly use the primary user's idle bandwidth which has been sensed. In this paper, to solve this problem, we propose the spectrum sharing algorithm which uses the multiple orthogonal sequences based on the code division multiple access(CDMA). From the proposed algorithm, it is expected that system performance of CR based ad-hoc network is improved significantly and it can be applied to the implementation of CR based ad-hoc network system.

The national regulation notice by a law has limitation values against electromagnetic interference by a power line. The kinds of induced voltages are very complicate. And the calculation methods are also difficult to handle in a legal notice. So the transition of legal practices is being processed. A standard is more convenient to comprise complicate parameters. To establish standardization, the contents of legal notice is modulized by the type of voltages and inducing plants. The inducing plants are electrified railway line - especially very high speed one - and general commercial power line. The induced voltages are longitudinal one and noise filtered one. The combination of voltages and plants is composed and classified. The plan to make standards step by step now has been errected.

H.264/AVC is international video coding standard, which shows improved code and efficiency than the existing video standards. H.264/AVC propose data partitioning method that considerably to be an effective layering technique which separates important addressing data from the residual data. UEP(Unequal Error Protection) Turbo code of H.264/AVC uses retransmission system to get the UEP effect. However, due to H.264/AVC possess effective data partitioning method, retransmission system is inefficient method in Turbo code of H.264/AVC. Based on this observation, we propose the new UEP turbo code algorithm that reconstruct input sequence of turbo code without retransmission system.

The technology to open Hardware as well as Software has been proposed in order to support software-based infrastructure. As legacy network equipment has a complex and closed architecture, it was hard to add new functions in it and to manage flows per application differently. Due to the emergence of the Software-Defined Networking(SDN), the idea of programmable networks is significantly considerable. Open Compute Project (OCP) focuses on supporting the most efficient computing infrastructure at the lowest possible cost, opening a network equipment as well as a server, and applying to commercial service. This paper surveys open hardware in case of network, a switch, and three approaches to build the switch.

Users get unexpected position information with errors because of satellite clock, ionospheric delay, tropospheric delay and hot noise. Especially if there are crowded many buildings and tall buildings in a small area, larger errors are generated by multi path, reflection and refraction. Therefore, in this paper, we have proposed a post-processing algorithm based on Minimum distance maintenance, Bounce cancellation and Direction vector scheme considering distribution and direction of received position information. Through the experimental results of this paper, we have shown a low average error 5.87m compared to the GPS point positioning that shows an average error 23.4m.

This paper aims to support tracking and managing of status information likes temperature, humidity for product and container truck as standard way in logistics fields. Attaching RFID tag on a sensor and when we reads container information at RFID gate, by reading sensor information together, we can write current business step and can represent hierarchy of information between container and sensors. We can converge RFID and sensor informations as standard way by providing sensor data transformed as RFID event data form.

Currently, it needs an introduction of the electric differential pricing for contribution to the stability of the power supply. And the renewable energy system is dramatically spreading to solve the lack of electricity power and save the electric charge. Therefore, the energy integrated management system is required that can be in consideration of the differential pricing and control renewable energy devices easily. In this paper, we present the integrated management system architecture of renewable energy and energy saving algorithm. The proposed system and algorithm can provide more economic benefit to residential customers.

Recently, the interest in u-healthcare service has been increasing. U-healthcare service will be able to provide ubiquitous and pervasive health monitoring in everyday life. Therefore, Biomedical signal has to accurately be detected for u-healthcare service in WBAN (Wireless Body Area Network) In this paper, we show various biomedical signals and a concept of biomedical signal detection techniques and recent technical trends for biomedical signal detection techniques for WBAN.

Disasters in recent times have distinct characteristics such as uncertainty, interactivity and complexity. These characteristics make disaster predictability decrease so that making us harder to manage with disasters. Therefore, the necessity of innovating disaster management system is highly required because the scale of damage is constantly increasing. Additionally, facilities which can have a massive life damage such as multiple-use facilities need a management solution using ICT and supply. In this paper, it makes possible to predict disasters such as collapse by monitoring and detecting it through consisting a multi-sensor network based on IOT and with analysing of data sensing from instruments. It also provides a solution to deal with a disaster by SOP and an information of spatial so that people in the area can evacuate fast and directly. Additionally, by analysis of a social data generating people in disaster sector, we can get the situation of disaster in real-time effectively and it can be minimize the damage of property and human life.

With the rapidly increasing power demand in recent years, variety of methods have been proposed for efficient power consumption.. Among them, the most representative example is demand response system based smart grid. Demand response system is not passive, one-side power demand. This system can efficiently consume through communication between service provider and power consumer. Demand response system uses HTTP based TCP/IP. And currently, there are variety of communication application protocol. In this paper, we analyze procotol type and application for demand response system.

Through the application of LED fixtures in the big auditorium of a community hall in Seoul, we can see that the energy used reduced greatly with the similar brightness as Halogen lights. Apart from the equipment cost, the energy cost was saved by 5.191 million won. Thus, if Halogen lights are replaced with LED lights in auditorium of similar size as 00 community hall, we can expect great saving of costs through energy saving.

Recent intensive initiative of a green energy by Japan government has brought discussion about new technology standardization for communication and energy management. Energy saving method is increasingly important in Home Network System. In order to get energy management system, the unified specifications are required in each device. As a result, several new standards needed to be followed i.e. ECHOENT lite, ARIB T-108, JJ300.10V1. This paper introduces the method of design for Wireless ECHOENT lite communication module design. This proposed method satisfies these requirements. Finally the protocol of the module was validated by using the ECHOENT Lite Tester.

Vertical Bell Lab Layered Space-Time is a spatial multiplexing (SM) multi-input multi- output (MIMO) scheme that provides high spectral efficiency with low computational complexity. Ordered Successive Interference Cancellation (OSCI) is known as most representative detection algorithm for SM MIMO system. Error propagation is a major drawback constraining the overall performance of OSIC detection significantly. To solve this problem, we propose a new detection algorithm, which improves the performance of the conventional detection algorithm with reasonable increase of computational complexity. Simulation results show that the proposed algorithm outperforms the conventional detection algorithm under spatially uncorrelated as well as correlated channels.

In this paper, we proposed a novel line coding scheme for efficient flicker free and dimming control in Visible Light Communication(VLC) systems. From the simulation results, it is confirmed that proposed scheme mitigates flicker noise and performs better dimming control compared to conventional VPPM(variable pulse position modulation) scheme.

In this paper, we introduce a concept of HEMP systems and analyze a shielding effectiveness by varying placements of the antenna elements. Maxwell's equations for the high frequency of the EMP is represented in the LOS. In order to investigate the effects of electromagnetic attenuations, a shielding room was constructed and employed to obtain measured data. The results of the paper can be applicable to design of concrete structures and the actual main protection facilities.

Commercial solar plants typically have a PV monitoring system which sends the plant information to a data server on the internet. Plant owners are sometimes forced to use wireless internet access, such as GSM/GPRS, CDMA, 3G or satellite communication, even though they wants to use cheap wired internet access. This is because they install the plant in remote rural areas where low-price internet access(e.g. ADSL) is not available in order to save the installation cost. The rate of mobile communications frequently depends on the amount of sent data. Therefore it is important to reduce the data size in a PV monitoring system. This paper proposes a communication method to reduce the data size without compression algorithm or data loss using PV plant data characteristics.