• Journal of the Korean Applied Science and Technology
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• v.21 no.4
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• pp.274-278
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• 2004

In this study, hetero-electrode structures have been fabricated to increase luminescence efficiency. The presence of a thin layer of Sn or Ag at the organic-aluminum interface enhanced both electron injection efficiency and electroluminescence when compared to OLEDs using homogeneous electrode. In this paper, the effect of the cathode using Sn/Al hetero electrode structure is observed. Electric properties of the OLED using Sn/Al hetero cathode are improved in comparison of only Al cathode. The hetero-electrode existing different energy level induces the advanced structure of OLED can accumulate electron density. The luminescence efficiency of OLED with Sn/Al of Ag/Al cathode is higher because of their higher electron injection efficiency. And, the turn on voltage of the OLED device using Sn thin layer is lowest as about 10 V.

• Journal of Adhesion and Interface
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• v.22 no.1
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• pp.1-7
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• 2021

The importance of high capacity energy storage devices has recently emerged for stable power supply through renewable energy generation. From this point of view, the Na-air battery (NAB), which is a next-generation secondary battery, is receiving huge attention because it can realize a high capacity through abundant and inexpensive raw materials. In this study, activated carbon-based catalysts for hybrid type Na-air batteries were prepared and their characteristics were compared and analysed. In particular, from the viewpoint of resource recycling, activated carbon (Orange-C) was prepared using discarded orange peel, and performance was compared with Vulcan carbon, which is widely used. In addition, a Pt/C catalyst (homemade-Pt/C, HM-Pt/C) was synthesized using a modified polyol method to check whether the prepared activated carbon can be used as a supported catalyst, and a commercial Pt/C catalyst (Commercial Pt/C) and electrochemical performance were compared. The prepared Orange-C exhibited a typical H3 type BET isotherm, which is evidence that micropore and mesopore exist. In addition, in the case of HM-Pt/C, it was confirmed through TEM analysis that Pt particles were evenly distributed on the activated carbon supported catalyst. In particular, the HM-Pt/C-based NAB showed the smallest voltage gap (0.224V) and good voltage efficiency (92.34%) in the 1st galvanostatic charge-discharge test. In addition, the cycle performance test conducted for 20 cycles showed the most stable performance.

• Journal of Korean Society of Archives and Records Management
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• v.21 no.3
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• pp.187-215
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• 2021

Archives should provide a web-based archival information service with good usability based on the understanding of users' needs. Thus, this study analyzed the usability of the National Archives of Korea (NAK) website's search service through expert and usability evaluations for various users and suggested improvement plans. A literature review, heuristic evaluation, one of the usability expert evaluation methods, and usability evaluation for users were performed. As a result of expert evaluation, the severity rating for the usability problem was highest regarding a match between the system and real world and the lowest in error prevention. In the usability evaluation, it was assumed that the user's background and whether the website's help was provided is associated with usability. Usability evaluation was conducted for 22 participants, including those majoring in records management, web/application developers, and people without such backgrounds. Furthermore, a presurvey, a five-second test, and search tasks were conducted in a row. The analysis based on usability components in ISO 9241-11: 2018, i.e., effectiveness, efficiency, and satisfaction, showed that web/application developers had the highest search effectiveness, and those majoring in records management showed high effectiveness only in the search for archival content services. Background factors did not affect efficiency, and the more familiar with the finding aids, the better the efficiency. Moreover, providing the website's help was found to be positively associated with effectiveness and satisfaction. This study suggests that the NAK website will offer a user-friendly interface and search function, expand help support, and display a consistent web interface.

• Steel and Composite Structures
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• v.13 no.3
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• pp.239-258
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• 2012

In this paper, experimental investigations on high strength steel (HSS) stud connected steel-concrete composite (SCC) girders to understand the effect of shear connector density on their flexural behaviour is presented. SCC girder specimens were designed for three different shear capacities (100%, 85%, and 70%), by varying the number of stud connectors in the shear span. Three SCC girder specimens were tested under monotonic/quasi-static loading, while three similar girder specimens were subjected to non-reversal cyclic loading under simply supported end conditions. Details of casting the specimens, experimental set-up, and method of testing, instrumentation for the measurement of deflection, interface-slip and strain are discussed. It is found that SCC girder specimen designed for full shear capacity exhibits interface slip for loads beyond 25% of the ultimate load capacity. Specimens with lesser degree of shear connection show lower values of load at initiation of slip. Very good ductility is exhibited by all the HSS stud connected SCC girder specimens. It is observed that the ultimate moment of resistance as well as ductility gets reduced for HSS stud connected SCC girder with reduction in stud shear connector density. Efficiency factor indicating the effectiveness of high strength stud connectors in resisting interface forces is estimated to be 0.8 from the analysis. Failure mode is primarily flexure with fracturing of stud connectors and characterised by flexural cracking and crushing of concrete at top in the pure bending region. Local buckling in the top flange of steel beam was also observed at the loads near to failure, which is influenced by spacing of studs and top flange thickness of rolled steel section. One of the recommendations is that the ultimate load capacity can be limited to 1.5 times the plastic moment capacity of the section such that the post peak load reduction is kept within limits. Load-deflection behaviour for monotonic tests compared well with the envelope of load-deflection curves for cyclic tests. It is concluded from the experimental investigations that use of HSS studs will reduce their numbers for given loading, which is advantageous in case of long spans. Buckling of top flange of rolled section is observed at failure stage. Provision of lips in the top flange is suggested to avoid this buckling. This is possible in case of longer spans, where normally built-up sections are used.

• Science of Emotion and Sensibility
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• v.11 no.4
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• pp.521-530
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• 2008

Graphical user interface design, the visual language to convey information about the icon and the user's information is a medium that can lead to action. Graphical user interface to communicate with the user icon, the user is easy to use, so any time you want to provide information effectively. Communication in order to increase the efficiency of the Graphic User Interface on the nature of the medium must be made to develop the appropriate icon. In this research icon of the type of icon painting. A picture of the icon representation of each type of detail, according to a rating of johyeongjeok identify the elements of the correlation between. On the type of representation of each of Art and Design elements that I know what I saw. The icon design based on user preferences provide guidance on the direction of design-oriented. When the data can be used to designs based on the theory has to offer.

• Journal of Internet Computing and Services
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• v.8 no.5
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• pp.45-58
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• 2007

This paper presents UI4GSD (User Interface for Grid Service Development) for grid service developers that provides an efficient and friendly development environment based on Globus Toolkit 4, Normally, implementing grid service requires special expert knowledge for Grid as well as programming, Moreover, grid service development as well as testing of the deployed service in the Globus container takes a long Time, which makes the grid service implementation very inefficient, However, UI4GSD can automatically generate a grid service interface file, a build file, and grid service class files as well as a client class file, using the information supplied by developers through GUI. In UI4GSD, a grid service is developed easily based on typical five step processes with required input data fed at each step. As, a result, UI4GSD can provide an easy and convenient development environment thereby increasing the efficiency and convenience in developing grid services.

• Journal of the Ergonomics Society of Korea
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• v.30 no.4
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• pp.551-562
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• 2011

Objective: We proposed an effective 3D menu manipulation alternative with a usability test. This was performed in a 3D environment with 3D menu and control manipulation methods. Background: As 3D stereoscopic displays became generalized, various 3D applications were being used not just movies, games, but also mobile contents and advertisements. However, when a user interface was designed in a 3D environment, it was lacked that a clear standard and result of an efficiency and usability as like a 2D environment. Method: We implemented 9 kinds of 3D menu types based on 3D menu hierarchies, menu layouts and dimensions. And we extracted 3 representative control types in a 3D environment. We performed usability evaluation with full factorial design for 27 menu alternatives with 2 types of menu manipulation tasks. In this condition, we measured the performance time, subjective discomfort and eye-fatigue. Results: A control type had the significant effect, and the effect of menu types had the different result depending on given tasks. Conclusion: This experiment showed the interaction of menu and control types depended on 3D menu manipulation tasks were significant in a 3D user interface design. Therefore, as a purpose of a 3D menu manipulation task, 3D menu types and control types were should be considered. Application: We supposed this result was should be applied in a 3D menu contents design.

• Journal of Korea Multimedia Society
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• v.13 no.8
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• pp.1221-1234
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• 2010

MANET(Mobile Ad-hoc Network)s have been researched primary at routing protocols and at the guarantees of QoS(Quality of Service) for mobile environments. Otherwise the Ubiquitous Sensor Networks (USNs) have some limitations in power energies and in processing of sensing data, as well as their network topologies are frequently changed by fading off and node failures. Thus we should redesign network protocols with concerning to energy efficiency for the USNs above all. In this paper, we focus on the protocol interface for managing for USNs based on the surveys. And then we figure the topology of USNs out and design the network protocol interface to make power saved, with data gathering and processing more efficient using our designed packet structures.

• Environmental Engineering Research
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• v.21 no.2
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• pp.152-163
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• 2016

Present study investigates the potential of cassava peel and rubber tree bark for the removal of Cr (VI) from aqueous solution. Removal efficiency of more than 99% was obtained during the kinetic adsorption experiments with dosage of 3.5 g/L for cassava peel and 8 g/L for rubber tree bark. By comparing popular isotherm models and kinetic models for evaluating the kinetics of mass transfer, it was observed that Redlich-Peterson model and Langmuir model fitted well ($R^2$ > 0.99) resulting in maximum adsorption capacity as 79.37 mg/g and 43.86 mg/g for cassava peel and rubber tree bark respectively. Validation of pseudo-second order model and Elovich model indicated the possibility of chemisorption being the rate limiting step. The multi-linearity in the diffusion model was further addressed using multi-sites models (two-site series interface (TSSI) and two-site parallel interface (TSPI) models). Considering the influence of interface properties on the kinetic nature of sorption, TSSI model resulted in low mass transfer rate (5% for cassava peel and 10% for rubber tree bark) compared to TSPI model. The study highlights the employability of two-site sorption model for simultaneous representation of different stages of kinetic sorption for finding the rate-limiting process, compared to the separate equilibrium and kinetic modeling attempts.

• 전기의세계
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• v.25 no.6
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• pp.8-13
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• 1976

The industrial processes have become complicated on a large scale bacause of improvement of productivity, research of efficiency, and shortage of locations to be suited for foundation of factories. Consequently, the instrumentation and control systems for operating these industrial processes have also been highly improved with the development of mass information means. In order to operate these large-sized and complicated industrial processes safely, the man-machine interface for correspondence between man and machines and the instrumentation system regarding process fault processing are playing an important role increasingly. This paper describes recent instrumentation system in the water purifying plant as an example of these industrial processes, and covers both man-machine interface and process fault processing. The annual water supply quantity and diffusion were 2, 000, 000, 000m$^{3}$ and 25.0% in 1950 inJapan, but they amounted to 12, 000, 000, 000m$^{3}$ and 86.7% in 1974, respectively. The demands of water will increase incessantly, while it becomes gradually difficult to secure water sources. Accordingly, local self-governing bodies such as municipal cooperation, towns, and villages often construct a large-scale water purifying plant at one place in common, as required, without constructing respective plants independently. It is an absolute requirement for the water purifying plant to avoid stopping water supply to fullfil its social responsibility from the viewpoints of its public utility enterprise, and also it has gradually become difficult to secure skilled operators enough to cover such water purifying plants that are additionally provided in various districts. Thus, the importance of the man-machine interface for assuring safety operation of the water purifying plant irrespective of unskillfulness of operators as well as the instrumentation system regarding process fault processing, or, safety instrumentation, is more and more increasing as the water purifying plants are on a large scale.