• ETRI Journal
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• v.38 no.3
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• pp.469-478
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• 2016

In this paper, we investigate the effects of pre-reducing Sb-doped $SnO_2$ (ATO) electrodes in viologen-anchored $TiO_2$ (VTO) nanostructure-based electrochromic devices. We find that by pre-reducing an ATO electrode, the operating voltage of a VTO nanostructure-based electrochromic device can be lowered; consequently, such a device can be operated more stably with less hysteresis. Further, we find that a pre-reduction of the ATO electrode does not affect the coloration efficiency of such a device. The aforementioned effects of a pre-reduction are attributed to the fact that a pre-reduced ATO electrode is more compatible with a VTO nanostructure-based electrochromic device than a non-pre-reduced ATO electrode, because of the initial oxidized state of the other electrode of the device, that is, a VTO nanostructure-based electrode. The oxidation state of a pre-reduced ATO electrode plays a very important role in the operation of a VTO nanostructure-based electrochromic device because it strongly influences charge movement during electrochromic switching.

• Journal of Information Technology Services
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• v.11 no.3
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• pp.161-175
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• 2012

A novel concept of ICT based service, which is called N-device service, is proposed and implemented in the form of N-device smart education services. The N-device services are different from the existing N-screen services in terms of the number of devices a user is using for a specific service at the same time. A N-device service consists of several smart devices which are different in size, software and hardware platform, mobility, manufacturer and the like by fully utilizing the characteristic of each device. The major and unique features of N-device services are analyzed and depicted in a strict way. Those are shared role for each device, service by configurable device, one sensor multiple use, real-time data sharing, role shifting and new market creation. It is turned out that the N-device service is more human centric compared with existing ICT based services and can give richer digital experience to users because non-existent services become possible with the new concept. However, there exist several barriers to be implemented and commercialized in the real world. Those include high development cost and time, small market and different application platforms of devices. These barriers can be overcome by technical advances and cooperation between relevant parties. The smart education is very prominent area, in which the novel concept can be applied with high priority because Korean government announced its plan to boost up new educational services with big budget and these are acceptable by enthusiastic Korean parents and students. That's why the N-device service is implemented in the education area, which is called as "livessam(live teacher)," with four smart devices, IPTV, tablet PC, PC and smart phone. By providing both detailed service scenario and techniques, we shows that the novel education service is technically feasible and acceptable by teachers and students.

• The Journal of the Korea Contents Association
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• v.16 no.11
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• pp.796-805
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• 2016

This study aimed to investigate the influence of the various factors ICT Convergence of Sports Game device on user satisfaction and intention to reuse. For this goal, based on the review of literature and the Extended Technology Acceptance Model, a research model was constructed that consists of playfulness, usefulness, convenience. The proposed model is analyzed to target 271 customers in Daegu National Science Museum experienced ICT Convergence Sports Game Device using Smart Partial Least Square(PLS) 2.0. The result of hypothesis testing are as follows. First, Playfulness, Usefulness, Convenience showed positively significant impact on Game satisfaction. Second, Game satisfaction positively influenced Reuse Intention. Thus, based on the results of the study, ICT Convergence of Sports Game Device seems to help in the development of a contents.

• Journal of the Microelectronics and Packaging Society
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• v.29 no.2
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• pp.99-105
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• 2022

As the chip size gets smaller, the width of the electrode line is also fine, and the density of interconnections is increasing. As a result, RC delay is becoming a problem due to the difference in resistance between the capacitor layer and the electrical conductivity layer. To solve this problem, the development of electrodes with high electrical conductivity and dielectric materials with low dielectric constant is required. In this study, we developed low dielectric ink by mixing commercial PSR which protect PCB's circuits from external factors and PI with excellent thermal property and low-k characteristics. As a result, the ink mixture of PSR and PI 10:3 showed the best results, with a dielectric constant of about 2.6 and 2.37 at 20 GHz and 28 GHz, respectively, and dielectric dissipation was measured at about 0.022 and 0.016. In order to verify the applicability of future applications, various line-width transmission lines produced on Teflon were evaluated, and as a result, the loss of transmission lines using low dielectric ink mixed with PI was 0.12 dB less on average in S21 than when only PSR was used.

• ETRI Journal
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• v.43 no.6
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• pp.1093-1102
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• 2021

Microdisplays based on organic light-emitting diodes (OLEDs) have a small form factor, and this can be a great advantage when applied to augmented reality and virtual reality devices. In addition, a high-resolution microdisplay of 3000 ppi or more can be achieved when applying a white OLED structure and a color filter. However, low luminance is the weakness of an OLED-based microdisplay as compared with other microdisplay technologies. By applying a tandem structure consisting of two separate emission layers, the efficiency of the OLED device is increased, and higher luminance can be achieved. The efficiency and white spectrum of the OLED device are affected by the position of the emitting layer in the tandem structure and calculated via optical simulation. Each white OLED device with optimized efficiency is fabricated according to the position of the emitting layer, and red, green, and blue spectrum and efficiency are confirmed after passing through color filters. The optimized white OLED device with color filters reaches 97.8% of the National Television Standards Committee standard.

• ETRI Journal
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• v.41 no.6
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• pp.820-828
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• 2019

A highly reliable conductive adhesive obtained by transient liquid-phase sintering (TLPS) technologies is studied for use in high-power device packaging. TLPS involves the low-temperature reaction of a low-melting metal or alloy with a high-melting metal or alloy to form a reacted metal matrix. For a TLPS material (consisting of Ag-coated Cu, a Sn96.5-Ag3.0-Cu0.5 solder, and a volatile fluxing resin) used herein, the melting temperature of the metal matrix exceeds the bonding temperature. After bonding of the TLPS material, a unique melting peak of TLPS is observed at 356 ℃, consistent with the transient behavior of Ag₃Sn + Cu₆Sn₅ → liquid + Cu₃Sn reported by the National Institute of Standards and Technology. The TLPS material shows superior thermal conductivity as compared with other commercially available Ag pastes under the same specimen preparation conditions. In conclusion, the TLPS material can be a promising candidate for a highly reliable conductive adhesive in power device packaging because remelting of the SAC305 solder, which is widely used in conventional power modules, is not observed.

• The Journal of Information Systems
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• v.23 no.4
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• pp.169-196
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• 2014

This study investigates how information and communication technology (ICT) can damage intellectual property rights (IPR) in the movie industry. Utilizing a survey questionnaire to gather information about the extensive use of ICT devices, including tablet PCs and smartphones, we demonstrate how digital piracy behavior is associated with various socio-demographic characteristics. Econometrically, since a large number of people do not engage in piracy activities, we adopt a zero-inflated negative binomial model. We find that people with tablet PCs are more likely to engage in the piracy of movies from peer-to-peer (P2P) sites. In particular, when we categorize ICT devices based on whether they are portable and allow downloads, we find that people with devices equipped with both functions are most likely to engage in movie piracy.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.32 no.2
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• pp.157-160
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• 2019

P(VDF-TrFE-CFE) (Poly (vinylidene fluoride-trifluoroethylene-chlorofluoroethylene)), which exhibits a high electrostriction of about 7%, can transmit tactile output as vibration or displacement. In this study, we investigated the applicability of P(VDF-TrFE-CFE) to wearable piezoelectric actuators. The P(VDF-TrFE-CFE) layers were deposited through spin-coating, and interspaced with patterned Ag electrodes to fabricate a two-layer $3.5mm{\times}3.5mm$ device. This layered structure was designed and fabricated to increase the output and displacement of the actuator at low driving voltages. In addition, a laser vibrometer and piezoelectric force microscope were used to analyze the device's vibration characteristics over the range of ~200~4,200 Hz. The on-off characteristics were confirmed at a frequency of 40 Hz.

• The Journal of the Korea institute of electronic communication sciences
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• v.10 no.4
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• pp.449-459
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• 2015

A lot of people were trapped in elevators without power supply when BLACK-OUT situation occurred in 2011. The telephone network of control room connected to the elevators had problem operating poorly. In this paper we propose an ICT based elevator emergency call device prototype system and evaluate the performance of the system. The proposed system quickly responds in emergency situation to guarantee passenger safety. For the goal, firstly the system tries to connect to a control room. If it fails the system attempts to call numbers for emergency contact and a rescue team sequentially. The system is designed to quickly support emergency contact as well. Finally, the information of elevator failure is rapidly transferred to the failure process device by the proposed system.

• Tunnel and Underground Space
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• v.32 no.3
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• pp.194-202
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• 2022

An increased number of cases have occurred in applying ICT technology in the resource development field due to factors such as safety, eco-friendliness, and low cost since the 2000s. In Korea, the 2nd mining master plan specified the significance of converging the full cycle of mining and ICT, while the 3rd mining master plan highlighted ICT and smart mining such as supporting the supply of an ICT mining device and introducing demonstrational smart mining. This study introduces the application of an ICT device and safety system operation in the Jangseong underground mine of Korea Cement Co., Ltd. Currently, Jangseong mine combines two different kinds of 3D equipment including the handheld 3D scanner and multi-station that provides both the measurement and 3D scanning to perform a 3D measurement of the mine. Taken from the 3D measurement of the mine, it is now possible to identify any hazardous areas and abnormalities in different directions and analyze the safety of the crown pillar between two stopes in different level. Besides, the real-time location tracking and communications system have established highly efficient rescue and evacuation plans to effectively deal with any accidents in the mine.