• Journal of Korea Multimedia Society
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• v.10 no.5
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• pp.604-611
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• 2007

Java Card has gained genera1 acceptance with standard for smart card and (U)SIM technology, and it is in distinction from native card by its post-issuance of an application and independence from hardware platforms. However, a main weak point of Java Card is its low execution speed caused by the hardware limitation and Java programming language itself. In this paper, we propose a new Java Card Installer to improve the download speed during the post-issuance of an application by resolving symbolic references to physical references in HAM. Our Resolution_In_RAM is based on the improved new RAM writing is 100,000 times faster than EEPROM writing and PageBuffer that is operated as block mode, rather than cell mode is used to write to EEPROM. Consequently, the total number of EEPROM writing are reduced 37%, and the times of downloading are reduced over 30% by using the Resolution_In_RAM-based Java Card Installer.

• Transactions of Materials Processing
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• v.21 no.6
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• pp.348-353
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• 2012

Micro-drawn parts have received wider acceptance as products become smaller and more precise. The subject of this study was the deformation characteristics of ultra thin sheet metal in micro drawing of a rectangular shaped part. The influence of drawing speed and blank holding force on the product quality was investigated in micro-drawing of ultra thin sheet of beryllium copper (C1720) alloy. The specimen had a diameter of 4.8 mm and a thickness of $50{\mu}m$. Experiments were carried out in which, different blank holding force and drawing speed were considered. The product quality was evaluated by measuring the thickness and hardness along two specified directions, namely, the side and diagonal directions. The distribution of the thickness strain showed severe thinning especially around the punch radius in both directions. In the diagonal direction, thickening occurred in the flange area due to the axi-symmetric drawing mode. The increase of blank holding force and/or drawing speed was found to cause severe thinning around the punch radius. The blank holding force had a greater effect on thinning of the product than the drawing speed.

• Journal of the Korea Society of Computer and Information
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• v.27 no.2
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• pp.71-80
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• 2022

Using the TAM, this study investigates the impact of Perceived Usefulness(PU), Perceived Ease of Use(PEOU) of the Animal-Crossing users on game satisfaction(DOS), immersion(DOI), and the relationship between user's attitude and intention through the google online survey. The decorative elements of the game generate a healing effect and more than half of the survey participants share game activities with the online community in terms of PU. In the case of PEOU, the survey participants positively evaluate the technological advancement such as graphics and sounds of the game. In addition, both high degree of satisfaction and immersion in the game have significant correlations with the intention for replaying the game and intention for recommending the game to others.

• Journal of Korea Society of Digital Industry and Information Management
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• v.11 no.3
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• pp.159-177
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• 2015

As smart phones become more common nowadays, mobile instant messengers such as kakao talk and line are used as essential communication tools exchanging information between individuals. Also, the mobile instant messengers extend their use to business area beyond communication between individuals. This study is on how factors of mobile instant messenger such as perceived security, perceived privacy, perceived enjoyment and perceived interactivity affect business continual usage intention through perceived usefulness. The proposed model is based on Expectation-Confirmation Theory of Oliver and Technology Acceptance Mode of Bhattacherjee. For an analysis, 159 survey responses were collected from the office workers in Seoul and nearby cities, having experiences of mobile instant messengers. To validate the proposed research model, PLS analysis is performed with the valid 154 questionnaires. The path analysis results are as follows. First, perceived security has a positive effect on expectation-confirmation. Second, perceived enjoyment has a positive effect on perceived usefulness. Third, perceived interactivity has a positive effect on both perceived usefulness and expectation-confirmation. Fourth, perceived usefulness has a positive usefulness on satisfaction and continual usage intention of mobile instant messenger. Last, expectation-confirmation has a positive effect on perceived usefulness, and satisfaction has a positive effect on continual usage intention of mobile instant messenger. Since the mobile instant messenger may bring a pressure of work and a violation of privacy, it is necessary that the company provide a guideline for use of the mobile instant messenger and establish the in-house mobile instant messenger system.

• Plant Journal
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• v.4 no.3
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• pp.60-65
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• 2008

Power plant industry has been developed at high-capacity, high-technology, and innovation. Steam turbine became the most useful equipment that dominate more than 50% of all the world electricity production. And developed new materials of the turbine blade and extended length of the turbine last blade brought reform in steam turbine performance upgrade. In this paper, when do partial load driving in high-capacity steam turbine, optimum driving method found whether there is something. In operating steam turbine, there is a lot of loss from secondary wake and throttle of the 1st stage nozzle by the biggest leading factor that load fluctuation affects in high-pressure steam turbine performance. Effect of internal efficiency by 1 stage nozzle is the biggest here, but here fluid flow and flow analysis were not yet examined closely definitely. So, Analyzed design data and acceptance performance test result to applying subcritical pressure drum type 560 MW, supercritical-pressure once through type 500 MW, and 800 MW steam turbines actually. In conclusion, at partial load driving, partial arc admission(PAA) is more efficient than full arc admission(FAA) efficiency. This is judged by because increase being proportional with gross energy of stream that is pressure - available energy if pressure of stream that is flowed in to the turbine increases, available energy becomes maximum and turbine efficiency improves. Therefore, turbine performance is that preview that first stage performance fell if decline is serious in partial load because first stage performance changes according to load.

• Analytical Science and Technology
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• v.32 no.5
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• pp.163-172
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• 2019

Methamphetamine (MA) is currently the most abused illicit drug in Korea and its major metabolite is amphetamine (AP). As MA exist as two enantiomers with the different pharmacological properties, it is necessary to determine their respective amounts in a sample. Thus a chiral stationary phase liquid chromatography-tandem mass spectrometric (LC-MS/MS) method was developed for identification and quantification of d-MA, l-MA, d-AP, and l-AP in human urine. Urine sample ($200{\mu}L$) was diluted with pure water and purified using solid-phase extraction (SPE) cartridge. A $5-{\mu}L$ aliquot of SPE treated sample solution was injected into LC-MS/MS system. Chiral separation was carried out on the Astec Chirobiotic V2 column with an isocratic elution for each enantiomer. Identification and quantification of enantiomeric MA and AP was performed using multiple reaction monitoring (MRM) detection mode. Linear regression with a $1/x^2$ as the weighting factor was applied to generate a calibration curve. The linear ranges were 25-1000 ng/mL for all compounds. The intra- and inter-day precisions were within 3.6 %, while the intra- and inter-day accuracies ranged from -5.4 % to 11.8 %. The limits of detection were 2.5 ng/mL (d-MA), 3.5 ng/mL (l-MA), 7.5 ng/mL (d-AP), and 7.5 ng/mL (l-AP). Method validation parameters such as selectivity, matrix effect, and stability were evaluated and met acceptance criteria. The applicability of the method was tested by the analysis of genuine forensic urine samples from drug abusers. d-MA is the most common compound found in urine and mainly used by abusers.

• The Journal of the Korea Contents Association
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• v.13 no.12
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• pp.149-167
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• 2013

This study focuses how storytelling in advertising has introduced and determinated mobile telecommunication technology as a digital technology in the process of its rapid acceptance into our society. The objective of the study is to confirm the role of advertising in introducing technology into a society and the relation between advertising and technology by chasing the digital discourse produced by advertising while digital technology permeates through our society. This study uses content analysis for basic research and discourse analysis for exploring the change of digital discourse in the corporate ads of mobile telecommunication companies since 15 years. As a result, 1) 'digital' and 'analogue' discourses were found to be competing and contesting with each other across the years. Digital discourse mainly connected to a new mode of thinking and lifestyle appeared predominant in the early period, but eventually gave way to its alternative, analogue dialogue. The analogue discourse was brought with such values as humanity, slowness and happiness, which has been by and large undermined by the new, fancy digital technologies and their world, 2) whereas some mixed forms of these two discourses were also found. 3) In the meantime, digital-based mobile communication technologies were identified with people who think outside of box and have an innovative attitude toward their life in the ads. Through this signification process, the ads contribute to permeation of mobile communication technology into our daily life.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.16 no.5
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• pp.189-203
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• 2021

Environmental changes, which are strongly requiring technological cooperation, such as technological development and strategic alliances according to industrial ecosystem change, have a significant impact on not only product quality but also services. Thus, there is a need for 'servitization' that can satisfy the needs of customers and the ecosystem of businesses through the convergence of manufacturing companies and services. This study uses the Expectation-Confirmation Model to examine the impact on user satisfaction and Continuance Usage Intention. Research(Study) was conducted on users who are using high-tech-based cars. For this, we used Expectation Confirmation(match expections for the user's pre-and post-use relationships), Perceived Ease, Perceived Usefulness, User Satisfaction and Habitual Use and using Continuance Usage Intention as a dependent variable. Their causation was examined with the spss 26.0 and smartpls 2.0 statistical programs. As implications of this study, Expectation Confirmation has been shown to have significant positive effects on Perceived Ease, Perceived Usefulness, User Satisfaction and Habitual Use. For this results, the expectations before and after the use of high-tech cars lead to improved daily lives convenience and(or) work efficiency, leading to user satisfaction and further Continuance Usage Intention. Motors consider it important to pursue the work improvements that consumers want and use it useful in daily lives in the production and sale of high-tech cars. It is expected that it will create natural habits for services that users are satisfied with, and that these habits will affect the continuous growth and understanding of the trend of change.