• Journal of Satellite, Information and Communications
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• v.5 no.2
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• pp.19-24
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• 2010

The COMS (Communication Ocean Meteorological Satellite) is a hybrid geostationary satellite including communication, ocean, and meteorological payloads. The COMS includes the MODCS (Meteorological and Ocean Data Communication Subsystem) which provides transmitting the raw data collected by meteorological payload called MI (Meteorological Imager) and ocean payload named GOCI (Geostationary Ocean Color Imager) to the ground station, and relaying the meteorological data processed on the ground to the end-user stations. Here, for the L-band transmit antenna transmitting SD (Sensor Data) signal and the processed signal, from the system point of view, it is required to estimate the combined antenna gain when the L-band transmit is placed with MI and GOCI payloads on the earth panel of COMS. First of all, the L-band transmit horn is designed and analyzed for the requirements given, and then after placing it on the earth panel, the combined gain analysis is performed using three different analysis methods. It's shown that the obtained gain patterns are very similar among three different analysis methods. Finally the antenna gain degradation of less than 0.5 dB is estimated.

• Journal of Drive and Control
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• v.10 no.2
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• pp.7-12
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• 2013

In this study, a wire/wireless communication system transmitting the operation data of engine from the ER (Engine Room) to the engine controller of ECR(Engine Control Room) has been developed through the communication of ISM(Industrial Science Medical) Band for the test operation environment improvement of medium speed engine. This wire/wireless communication system is composed of the RTU (Remote Terminal Unit) gathering and transmitting engine data as well as the MCU (Master Control Unit) receiving engine status information from the RTU to be sent to the engine controller (PLC). Through this study, a trial product of RTU and MCU has been manufactured. A test bench that has made temperature, pressure and pick-up sensor into a module for the local test of prototype was produced a test bench. In addition, at the same time save the data to a Web server and the smart phone real-time monitoring system has been developed using Wi-Fi communications. The ultimate objective of this study is to develop a wireless smart phone monitoring system of engine for the operator of engine to be able to monitor and control engine status even from the outside of engine room and control room based on this study.

• Journal of Convergence Society for SMB
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• v.1 no.1
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• pp.39-44
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• 2011

Recently, due to people's incontinent use all over the world, fossil fuels such as coal, oil, and natural gas were nearly to be exhausted and also causes serious environment pollutions. Therefore, there is a strong need to develop solar, wind, hydro, biomass, geothermal to replace fossil fuels to prevent suffering from above problems. Wish advances in sensor technology, such data is collected as a kind of stream data which arrives in an online manner so that it is characterized as high- speed, real-time and unbounded and it requires fast data processing to get the up-to-date results. Therefore, the traditional data processing techniques are not fit to deal with stream data. In this paper, we propose a kalman filter-based algorithm to process renewable stream data.

• Spatial Information Research
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• v.17 no.4
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• pp.445-454
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• 2009

Beyond simple transfer of information through sensor network, this study will provide the insights about the way to embody the real context aware location based service in an ubiquitous computing environment. In this paper, a new formal approach is introduced to derive knowledge about the scope of influence for a point object. A scope of influence is defined as the conceptual area where there is a possibility of the phenomenon or event occurring because of this point object. A point object can be spatially extended by considering this scope of influence in conjunction with the point. These point objects are called Spatially Extended Point (SEP) objects. Compositions of gradual changes of topological relations between a SEP and the environment near the SEP show how to represent the qualitative spatial behaviors of a SEP objects. These qualitative spatial behaviors will be good standards for Location Based Service (LBS) to provide more subdivided and suitable information to the users.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.12 no.1
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• pp.211-216
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• 2012

Control Theory for continuous-time system has been well developed. Due to the development of computer technology, digital control scheme are employed in many areas. When delays are in control systems, it is hard to control the system efficiently. Delays by controller-to-actuator and sensor-to-controller deteriorate control performance and could possibly destabilize the overall system. In this paper, a new approximated discretization method and digital design for control systems with multiple state, input and output delays and a generalized bilinear transformation method with a tunable parameter are also provided, which can re-transform the integer time-delayed discrete-time model to its continuous-time model. Illustrative example is given to demonstrate the effectiveness of the developed method.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.12 no.1
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• pp.283-294
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• 2012

Recently increasing usage of smart phones so, the application field of convergence industry between IT technology using smart phone-based mobile communication networks and other industry branches is expanding. In addition, R&D technologies in other fields are applied to smart phone applications effectively in order to develop products and support daily life more convenient. However, it is very hard to control these products and there is no efficient solution for this problem when many people are sent to specific area for big events, such as Biennale, Film Festival, EXPO, and so on. In order to solve this problem, this paper describes a network-based ticket reservation system and its organization using augmented reality on smart phone and mobile communication networks. In particular, we propose a method of designing and developing prototyping system based on smart phone application design technologies, prior to developing real smart phone application.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.17 no.2
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• pp.45-50
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• 2017

Micro-service Architecture is a service architecture optimized for large-scale distributed systems such as real-time realistic broadcasting systems, so that are fiercely adopted by Global leading service platform vendors such as Netflix and Twitter due to the merit of horizontal performance scalability enabling the scale-out technique. In addition, micro-service architecture makes it possible to execute image processing and real-time data analysis using an asynchronous-based processing that are difficult to handle in Web API such as REST. In this paper, an event stream processing framework applicable to asynchronous based micro services is proposed in the sense that the accountability of event processing order is not guaranteed in the events such as IoT sensor data analysis or cloud-based image editing because these are the situations where the real-time media editing generates multiple event streams and asynchronous processes in the platform.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.20 no.4
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• pp.17-22
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• 2020

Behavior-based authentication technology, which is currently being researched a lot, requires a long extraction of a lot of data to increase the recognition rate of authentication compared to other authentication technologies. This paper uses the touch sensor and the gyroscope embedded in the smartphone in the Android environment to measure five times to the user to use only the minimum data that is essential among the behavior feature data used in the behavior-based authentication study. By requesting, a total of six behavior feature data were collected by touching the five touch screen, and the mean value was calculated from the changes in data during the next touch measurement to measure the cosine similarity between the value and the measured value. After generating the allowable range of cosine similarity by performing, we propose a user behavior based authentication method that compares the cosine similarity value of the authentication attempt data. Through this paper, we succeeded in demonstrating high performance from the first EER of 37.6% to the final EER of 1.9% by adjusting the threshold applied to the cosine similarity authentication range even in a small number of feature data and experimenter environments.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.20 no.5
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• pp.15-23
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• 2020

Automated driving car is drawing attention as a seminal service representing 4th industrial revolution era based on 5G network, AI, IOT and sensor technology. automated driving car is expected to evolve into the final level which does not require driver's input. Drivers are able to consume new additional time in private space. Many industries started to compete to control these time and space. Media industry is expecting quite big change due to the introduction of automated driving cars. This research examines the impact of the media industry and social & institutional issues of automated driving cars based on depth interviews of experts. The introduction of automated driving cars is giving new opportunity for media industry as contents provider. Telcos and IT corporations are expected to compete each other to get the control of infotainment systems of automated driving cars. The reform of current regulations regarding car driving is pointed as important task to protect private information and the introduction of automated driving cars.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.9 no.3
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• pp.280-285
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• 1999

$\alpha$-$Fe_2O_3$ thin film gas sensors were deposited at various temperature by CVD method. Polycrystalline $\alpha$-$Fe_2O_3$ thin films were deposited at $175^{\circ}C$ and $200^{\circ}C$. $\gamma$-$\alpha$-$Fe_2O_3$ phase was obtained when the deposition temperature was higher than $250^{\circ}C$. The crystallite size of $\alpha$-$Fe_2O_3$ was affected by the deposition and annealing temperature. The specimen deposited at $175^{\circ}C$ showed maximum sensitivity. In this condition, the sensitivity of $\alpha$-$Fe_2O_3$ thin film for NO gas (at 250 ppm) was 3.2 and response time (at 100ppm) was 12 second.