• Ocean and Polar Research
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• v.27 no.4
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• pp.451-461
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• 2005

The $CO_2$ storage in geologic and oceanic reservoirs is considered to be one of the carbon management strategies for responding to global climate change. Ocean carbon sequestration is purposeful storage acceleration into the ocean of large amounts of carbon that would accumulate in the atmosphere and naturally enter the ocean over a longer timespan. Some technologies for $CO_2$ ocean sequestrations have been developed as a nation project. However, $CO_2$ ocean sequestrations are attractive because they have the advantage of vast capacity sequestration far away from industrial areas, and offer easier monitoring whereas less economic advantage has been indicated as one of the key barriers compared with $CO_2$ geosphere sequestration, which is produced as a byproduct. In this paper, a conceptual design for $CO_2$ ocean sequestration is introduced, and the preliminary examination is described. As a result, the $CO_2$ price, US$ 24/t shows far away from the economics. The causes come from the expensive $CO_2$ recovery cost and the low $CO_2$ price. The expensive $CO_2$ recovery cost is because too much electricity and water are consumed. In order to look for an economic balance point for $CO_2$ ocean sequestration, NPV=0, it is increases the $CO_2$ price. Finally 60.4$ per ton is found to be the balance price.

• Culinary science and hospitality research
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• v.4
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• pp.249-269
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• 1998

What satisfies the desire of human beings about taste most easily is sweet taste, and it has seemed that the pronoun of sweet taste is sugar. Sugar is used in confectionery and bread-making essentially, and it has influence on the structure and touch of baked confectionery. In addition, if we soften the and apply heat, coloring is made. Thus, it colors good. It doesn't have a sweet taste, but it has the effect to emit fragrance variously, balance and soften the product. The kinds of sugar are very diverse, and it is sugar to be referred to as white sugar is used most frequently. In this study, this researcher examined the classification of physicochemical property and melting point etc. of sugar in confectionery and bread-making through theoretical study, about the simple classification of sugar. In addition, this researcher approached about the role of sugar in confectionery and bread-making and about the influence to have when it is more or less than proper quantity, centering around function. As the result, this researcher extracted the importance of sugar in confectionery and bread-making. It means that the increase of 5% of sugar quantity decreases the absorption quantity of moisture by 1% in bread-making and that the excess of 8% of sugar slow the action of yeast in straight method. Besides, there are the properties such as absorptive property, permeability, storage nature, aging prevention of starch, oxidation restraint of oils and fats, the gelation action of pectin, the fermentation acceleration of yeast, and the emulsification-maintaining-nautre and antiseptics effect of fat-soluble material. And in confectionery, sugar makes fragrance and peel color, increases the storage nature with moisture maintenance and has the softening effect. So, it is considered that the attitude to study and make efforts continuously on the basis of the role of sugar will have to be unfolded in confectionery and bread-making.

• Elastomers and Composites
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• v.55 no.2
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• pp.81-87
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• 2020

Service life prediction and evaluation of rubber components is the foundational technology necessary for securing the safety and reliability of the product and to ensure an optimum design. Even though the domestic industry has recognized the importance thereof, technology for a systematic design and analysis of the same has not yet been established. In order to develop this technology, identifying the fatigue damage parameters that affect service life is imperative. Most anti-vibration rubber components had been damaged by repeated load and aging. Hence, the evaluation of the fatigue characteristics is indispensable. Therefore, in this paper, we propose a method that can predict the service life of rubber components relatively accurately in a short period of time. This method works even in the initial designing stage. We followed the service life prediction procedure of the proposed rubber components. The weak part of the rubber and the maximum strain were analyzed using finite element analysis of the rubber bushing for the tracked vehicles. In order to predict the service life of the rubber components that were in storage for a certain period of time, the fatigue test was performed on the three-dimensional dumbbell specimen, based on the results obtained by the rubber material acceleration test. The service life formula of the rubber bushing for tracked vehicles was derived using both finite element analysis and the fatigue test. The service life of the rubber bushing for tracked vehicles was estimated to be about 1.7 million cycles at room temperature (initial stage) and about 400,000 cycles when kept in storage for 3 years. Through this paper, the service life for various rubber parts is expected be predicted and evaluated. This will contribute to improving the durability and reliability of rubber components.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.22 no.6
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• pp.1345-1354
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• 2012

The modern society with the wide spread USB memory, witnesses the acceleration in the development of USB products that applied secure technology. Secure USB is protecting the data using the method as device-based access control, encryption of stored files, and etc. In terms of forensic analyst, to access the data is a lot of troubles. In this paper, we studied software-based data en/decryption technology and proposed for analysis mechanism to validation vulnerability that secured on removable storage media. We performed a vulnerability analysis for USB storage device that applied security mechanism. As a result, we found vulnerabilities that extracts a source file without a password.

• Korean Chemical Engineering Research
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• v.52 no.2
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• pp.166-174
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• 2014

This research investigated the aging properties of the $B-KNO_3$ system as the igniter. The $B-KNO_3$ system showed the degradation in ignition properties depending on the method and period of storage. It should be found out the cause of the degradation to predict the reliability of the igniters. The changes of the properties by the degradation after aging tests were analyzed by microstructure analysis, XRD analysis and thermal analysis using DSC. It was found out that the lattice parameters of the $KNO_3$ as the oxidizer in the ignition system was changed into the JCPDS values as the aging time increased. Conclusively, the changes of the crystal structure of oxidizer affected the activation energy increasing as aging time increased.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.54 no.11
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• pp.561-568
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• 2005

This paper proposes a method that distributes the load power and stores the regenerated energy for a hoist-load system using the supercapacitor, an energy storage device. The crane, which is a representative hoist-load system, operates in two modes. The first is the hoist-up mode in which the load container is lifted up: the maximum power is required at the end of acceleration. The second is the hoist-down mode in which the load container is lifted down; the regenerated energy is wasted by the resistor In this paper, the supercapacitor stores the regenerated energy in the hoist-down operation and supplies the peak power demand in the hoist-up operation. The same structure as the commercially available three-phase inverter is proposed as a bidirectional do-dc converter to charge and discharge the supercapacitor. A power control algorithm is proposed to optimize the load sharing between the generator and the supercapacitor. Using the proposed method, it is effected that the generator size can be cut down to one third of the original one; it leads to the reduction of the fuel consumption, noise and air pollution. Simulation and experimental results verify the effectiveness of the Proposed method.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.2
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• pp.1420-1425
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• 2015

Lately, information and communications environmentis in accordance with the smartphone release is changing the paradigm of working environments setting a high value on mobility and efficiency as well as the ecosystem of information and communication technologies. In this paper, we proposed smart work-based IT system modeling suitable for SMEs in order to transform the paradigm of working environments, strengthen the competitiveness of SMEs, and to establish a foundation on which SMEs could leap to the global economy, by fostering the acceleration of information service implementation and smart work foundation. We conducted a survey of the change in awareness and creation of smart work environment targeting companies with less than thirty workers and proved it. will also contribute to smart work diffusion in SMEs by drawing a positive result of more than 75%.

• Nuclear Engineering and Technology
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• v.48 no.2
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• pp.505-517
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• 2016

The structural integrity of a dual-purpose metal cask currently under development by the Korea Radioactive Waste Agency (KORAD) was evaluated, through numerical simulations and a model test, under high-speed missile impact reflecting targeted aircraft crash conditions. The impact conditions were carefully chosen through a survey on accident cases and recommendations from literature. In the impact scenario, a missile flying horizontally hits the top side of the cask, which is freestanding on a concrete pad, with a velocity of 150 m/s. A simplified missile simulating a commercial aircraft engine was designed from an impact loade-time function available in literature. In the analyses, the dynamic behavior of the metal cask and the integrity of the containment boundary were assessed. The simulation results were compared with the test results for a 1:3 scale model. Although the dynamic behavior of the cask in the model test did not match exactly with the prediction from the numerical simulation, other structural responses, such as the acceleration and strain history during the impact, showed very good agreement. Moreover, the containment function of the cask survived the missile impact as expected from the numerical simulation. Thus, the procedure and methodology adopted in the structural numerical analyses were successfully validated.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.10a
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• pp.698-701
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• 2005

We have investigated experimentally a nano patterning using electron beam lithography for the nickel stamper fabrication. Recently, DVD and Blu-ray disk(BD) have nano-scale patterns in order to increase the storage density. Specially, BD has 100nm-scale patterns which are generally fabricated by electron beam lithography. In this paper, we found optimum condition of electron-beam lithography for 100nm-scale patterning. We controlled various conditions of EHP(acceleration voltage), beam current, dose and aperture size in order to obtain optimum conditions. We used 100nm-thick PMMA layer on a silicon wafer as photoresist. We found that EHP was the most dominant factor in electron-beam lithography.

• Smart Structures and Systems
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• v.6 no.5_6
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• pp.661-673
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• 2010

This paper presents recent developments in an extremely compact, wireless impedance sensor node (the WID3, $\underline{W}$ireless $\underline{I}$mpedance $\underline{D}$evice) for use in high-frequency impedance-based structural health monitoring (SHM), sensor diagnostics and validation, and low-frequency (< ~1 kHz) vibration data acquisition. The WID3 is equipped with an impedance chip that can resolve measurements up to 100 kHz, a frequency range ideal for many SHM applications. An integrated set of multiplexers allows the end user to monitor seven piezoelectric sensors from a single sensor node. The WID3 combines on-board processing using a microcontroller, data storage using flash memory, wireless communications capabilities, and a series of internal and external triggering options into a single package to realize a truly comprehensive, self-contained wireless active-sensor node for SHM applications. Furthermore, we recently extended the capability of this device by implementing low-frequency analog-to-digital and digital-to-analog converters so that the same device can measure structural vibration data. The compact sensor node collects relatively low-frequency acceleration measurements to estimate natural frequencies and operational deflection shapes, as well as relatively high-frequency impedance measurements to detect structural damage. Experimental results with application to SHM, sensor diagnostics and low-frequency vibration data acquisition are presented.