• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.2D
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• pp.295-302
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• 2011

Ubiquitous is an information communication environment which peoples could connect on network without being conscious of the network and computer condition at anytime and anywhere. Presently, advanced technology, digital cities and eco-friendly cities using Ubiquitous technology are being focused through out the world. As recent information industry and communication technology have developed remarkably, studies on intelligent structures and structural maintenance methods by combining a general idea of connecting all objects on network by interpolating computers which is called Ubiquitous Computing, and USN(Ubiquitous Sensor Network) are being attempted. In this paper, a basic experiment on penetration of RF(Radio Frequency) sensor nodes using an experimental sample setting concrete and reinforcing bar as variables is studied to estimate the possibility of applying wireless sensor networks in structures. The spring of reinforcing bars, concrete thickness, intensity of radio frequency were set up as variables, transmitting and receiving distance were checked vertically and horizontally. Moreover, Spectrum Analyzer was used for checking the magnitude of the frequency used in order to measure the reduction of radio wave exactly. The radio wave reduction was numerically analyzed, and the influence of the wavelength was analysed as well. As a result, the penetration depth in concrete without reinforcing bars was 45cm, and in reinforced concretes which reinforcing bars placed at spacing of 5cm and 15cm, the penetration depth were 37cm and 45cm each. No influence on radio wave penetration depth were found when the spacing of reinforcing bars in the reinforced concrete structures becomes over 15cm.

• Journal of the Korean Association of Geographic Information Studies
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• v.14 no.2
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• pp.40-52
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• 2011

In this study, $CO_2$ emission quantities by spatial characteristics using GIS were investigated for building a $CO_2$ emission inventory. Eventually, this study provides the guidelines to build the urban spatial structure for reducing greenhouse gas and contributes to the transition to environmental friendly green city. The attribute data for GIS were energy (electricity and gas) usage in the city of Daegu for 2009 and used for Tier 1 as suggested by the IPCC guideline to estimate amount of $CO_2$ emission. The spatial data were built based on land use types categorized by building purposes with connecting building registers to cadastral maps for Daegu city. Spatial $CO_2$ emission quantities could be calculated by combining $CO_2$ emission inventory for energy and GIS. Also, $CO_2$ emission characteristics were different by land use types.

• Journal of the Korea Society of Computer and Information
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• v.17 no.12
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• pp.31-39
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• 2012

In this paper, we propose a microprocessor-based automatic voltage regulator(AVR) to reduce consumers' electric energy consumption and to help controlling peak demanding power. Hybrid Switching Automatic Voltage Regulator (HS-AVR) consist of a toroidal core, several tap control switches, display and command control parts. The coil forms an autotransformer which has a serial main winding and four parallel auxiliary windings. It controls the output voltage by changing the combination of the coils and the switches. Relays are adopted as the link switches of the coils to minimize the loss. To make connecting and disconnecting time accurate, relays of the circuit have parallel TRIACs. A software phase locked loop(PLL) has been used to synchronize the timings of the switches to the voltage waveform. The software PLL informs the input voltage zero-crossing and positive/negative peak timing. The traditional voltage transformers and AVRs have a disadvantage of having a large mandatory capacity to accommodate maximum inrush current to avoid the switch contact damage. But we propose a suitable AVR for every purpose in smart grid with reduced size and increased efficiency.

• Korean Chemical Engineering Research
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• v.51 no.3
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• pp.358-363
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• 2013

Lithium-ammonia (Li-$NH_3$) solutions are possible to be successfully made under the vacuum condition but there still remains a problem of undergoing stable and reliable decomposition in vacuum for high-efficiency thermoelectric power generation. This paper describes a new method for improving the thermoelectric conversion efficiency of Li-$NH_3$ solutions in vacuum. The proposed method uses a 'U'-shaped Pyrex vacuum tube for the preparation and decomposition of pure fluid Li-$NH_3$ solutions. The tube is shaped so that a gas passageway ('U') connecting both legs of the 'U' helps to balance pressure inside both ends of the tube (due to $NH_3$ gasification) during decomposition on the hot side. Thermoelectric experimental results show that solution reaction in the 'U'-shaped tube proceeds more stably and efficiently than in the 'U'-shaped tube, and consequently, thermoelectric conversion efficiency is improved. It is also proved that the proposed method can provide a reversible reaction, which can rotate between synthesis and decomposition in the tube, for deriving the long-time, high-efficiency thermoelectric power.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.13 no.3
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• pp.623-628
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• 2009

The emergence of compact and low-power wireless communication sensors and actuators in the technology supporting the ongoing miniaturization of processing and storage allows for entirely the new kinds of embedded systems. These systems are distributed and deployed in environments where they may have been designed into a particular control method, and are often very dynamic. Collection of devices can communicate to achieve a higher level of coordinated behavior. Wireless sensor nodes deposited in various places provide light, temperature, and activity measurements. Wireless sensor nodes attached to circuits or appliances sense the current or control the usage. Together they form a dynamic and multi-hop routing network connecting each node to more powerful networks and processing resources. Wireless sensor networks are a specific-application and therefore they have to involve both software and hardware. They also use protocols that relate to both applications and the wireless network. Wireless sensor networks are consumer devices supporting multimedia applications such as personal digital assistants, network computers, and mobile communication devices. Wireless sensor networks are becoming an important part of industrial and military applications. The characteristics of modem embedded systems are the capable of communicating adapting the different operating environments. In this paper, We designed and implemented sensor network system which shows through host PC sensing temperature and humidity data transmitted for wireless sensor nodes composed wireless temperature and humidity sensor and designs sensor nodes using embedded system with the intention of studying USN.

• Journal of the Korean Society for Library and Information Science
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• v.49 no.3
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• pp.209-231
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• 2015

The main purpose of this study is to develop and apply a means of connecting reading movement and Newspaper In Education (NIE) activities utilizing the voluntary participation and cooperation of local school districts and autonomous government entities. This is necessary to revitalize or systematize the environmental social life of reading newspapers and NIE activity. Literary or inquiry research will be initiated in this study in order to quantify the current or actual conditions of this connection, delineating the basic objectives of this study, and determining the developmental directions for continuing this study as related to the connection of reading movement and NIE activity. Anticipated study activities or major tasks are as follows. First, develop a variety of intended programs and learning materials necessary for each. Secondly, develop and establish corresponding online data and educational programs. Thirdly, a "cooperation" system must be established and training programs implemented reinforcing these ideas. And, lastly (and to gain wider acceptance), starting a public relations campaign to show or illustrate the benefits of this study and these intended research activities. In conclusion, if a connection between reading movement and NIE activity are fully established and periodically adjusted by means of continuing discussions on the merits or concerns based on the study findings, the full potential of the reading movement connection with NIE activity will be realized and achieved to its truest meaning and/or highest order.

• Journal of Fashion Business
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• v.20 no.4
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• pp.189-206
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• 2016

A breast model was for the human body was devised by studying a body scan and human body index of a desirable breast type. Thus, when manufacturing various 3D models, these results can accordingly become a fundamental basis for realizing a desirable breast model. This study aims to provide a basic data for designing the cup patterns of brassieres in order to improve the function and wearing comfort. The comfort of three kinds of brassieres were compared: one manufactured by the actual measured size; another manufactured as per the ratio of desirable upper and lower breast lengths; and the third manufactured by the 3D model attained by the desirable human body ratio. In this study, we suggest a process for realizing the desirable breast model using the ratio of bust breadth and waist front length, which are the components for deciding the appropriate position and size of breast, and which are easy to measure. The ideal breast shape is an equilateral triangle formed by connecting the nipple with the center of the clavicle. After deciding the interval between the nipples, this value can be used to configure the locations of nipples by drawing a tangent, with equal length, from the anterior neck point (which is the center of clavicle) to the nipple. Also, since inside points of breast do not exist, the outer point of breast, upper point of breast, and below point of breast on the same plane, and the depths from the nipple point to the respective points, are applied to simulate a 3D image, by modifications along the x, y, and z axes. Depending on the type of breast, the length from the center of shoulder to the nipple, the diameter of breast, upper length of breast, and the position of nipple, are different. In conical or protruding breast, the wearing sensation is better when the nipple point of brassiere was lifted, by modifying the upper and lower lengths of breast. Considering the wearing sensation and function of a brassiere, it was better to leave the wearer's size as it is and use a pad within the same cup, rather than increase the basal area of the breast in order to increase the volume.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.9
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• pp.745-752
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• 2016

In the era of the Internet of Things, where all physical objects are connected to the Internet, we suggest a remote control system using a Raspberry Pi single-board computer with ZigBee, which can turn an indoor light-emitting diode (LED) and a multiple-tap on and off, and with a smart phone can control the brightness of the LED as well as an electronic door lock. By connecting an infrared (IR) transmitter module to the Raspberry Pi, we can control home appliances, such as an air conditioner, and we can also monitor indoor images, indoor temperatures, and illumination by using a smart phone app. We developed a method of finding out IR transmission codes required for remote-controllable appliances with an AVR micro-controller. We suggest a method to remotely open and shut an office door by novating the door lock. The brightness level of an LED (between 0 and 10) can be controlled through a PWM signal generated by an ATmega88 microcontroller. A mutiple-tap is controlled using an ATmega32, a photo-coupler, and a TRIAC. The signals for measured temperature and illumination are converted from analog to digital by using the ATtiny44A microcontroller transmitting to a Raspberry Pi through SPI communication. Then, we connect a camera to the CSI head of the Raspberry Pi. We can turn on the smart multiple-tap for a certain period of time, or we can schedule the multi-tap to turn on at a specific time. To reduce standby power, people usually pull out a power code from multiple-taps or turn off a switch. Our method helps people do the same thing with a smart phone, if they are away from home.

• Journal of the Institute of Electronics and Information Engineers
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• v.52 no.11
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• pp.87-104
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• 2015

Currently the IoT (Internet of Things) environments and related technologies are being developed rapidly through the networks for connecting many intelligent objects. The IoT is providing artificial intelligent services combined with context recognition based knowledge and communication methods between human and objects and objects to objects. With the help of IoT technology, many research works are being developed using the C-ITS (Cooperative Intelligent Transport System) which uses road infrastructure and traveling vehicles as traffic control infrastructures and resources for improving and increasing driver's convenience and safety through two way communication such as bus-only lane and license plate recognition and road accidents, works ahead reports, which are eventually for advancing traffic effectiveness. In this paper, a system for deciding whether the traveling vehicle is possible or not to drive on bus-only lane in highway is researched using the lane and number plate recognition on the road in C-ITS traffic infrastructure environments. The number plates of vehicles on the straight ahead and sides are identified after the location of bus-only lane is discovered through the lane recognition method. Research results and experimental outcomes are presented which are supposed to be used by traffic management infrastructure and controlling system in future.

• Journal of the Korea Society of Computer and Information
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• v.26 no.12
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• pp.151-158
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• 2021

Internet of Things (IoT) technology, which provides services by connecting various objects in the real world and objects in the virtual world based on the Internet, is emerging as a technology that enables a hyper-connected society in the era of the 4th industrial revolution. Since IoT technology is a convergence technology that encompasses devices, networks, platforms, and services, various studies are being conducted. Among these studies, studies on measures that can measure service quality provided by IoT software are still insufficient. IoT software has hardware parts of the Internet of Things, technologies based on them, features of embedded software, and network features. These features are used as elements defining IoT software quality measurement metrics. However, these features are considered in the metrics related to IoT software quality measurement so far. Therefore, this paper presents a metric for reusability measurement among various quality factors of IoT software in consideration of these factors. In particular, since IoT software is used through IoT devices, services in IoT software must be designed to be changed, replaced, or expanded, and metrics that can measure this are very necessary. In this paper, we propose three metrics: changeability, replaceability, and scalability that can measure and evaluate the reusability of IoT software services were presented, and the metrics presented through case studies were verified. It is expected that the service quality verification of IoT software will be carried out through the metrics presented in this paper, thereby contributing to the improvement of users' service satisfaction.