• Earthquakes and Structures
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• v.11 no.6
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• pp.1101-1121
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• 2016

Base isolation, one of the popular seismic protection approaches proven to be effective in practical applications, has been widely applied worldwide during the past few decades. As the techniques mature, it has been recognised that, the biggest issue faced in base isolation technique is the challenge of great base displacement demand, which leads to the potential of overturning of the structure, instability and permanent damage of the isolators. Meanwhile, drain, ventilation and regular maintenance at the base isolation level are quite difficult and rather time- and fund- consuming, especially in the highly populated areas. To address these challenges, a number of efforts have been dedicated to propose new isolation systems, including segmental building, additional storey isolation (ASI) and mid-storey isolation system, etc. However, such techniques have their own flaws, among which whipping effect is the most obvious one. Moreover, due to their inherent passive nature, all these techniques, including traditional base isolation system, show incapability to cope with the unpredictable and diverse nature of earthquakes. The solution for the aforementioned challenge is to develop an innovative vibration isolation system to realise variable structural stiffness to maximise the adaptability and controllability of the system. Recently, advances on the development of an adaptive magneto-rheological elastomer (MRE) vibration isolator has enlightened the development of adaptive base isolation systems due to its ability to alter stiffness by changing applied electrical current. In this study, an innovative semi-active storey isolation system inserting such novel MRE isolators between each floor is proposed. The stiffness of each level in the proposed isolation system can thus be changed according to characteristics of the MRE isolators. Non-dominated sorting genetic algorithm type II (NSGA-II) with dynamic crowding distance (DCD) is utilised for the optimisation of the parameters at isolation level in the system. Extensive comparative simulation studies have been conducted using 5-storey benchmark model to evaluate the performance of the proposed isolation system under different earthquake excitations. Simulation results compare the seismic responses of bare building, building with passive controlled MRE base isolation system, building with passive-controlled MRE storey isolation system and building with optimised storey isolation system.

• Journal of Korea Multimedia Society
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• v.13 no.5
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• pp.710-721
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• 2010

Recently, for the advancement of embedded technology about mobile device, a new kind of service, mash-up is appeared. It is service or application combining multimedia content making tool or device and web-GIS(geographic information system) service in the mobile environment. This service can be ease to use for casual user and can apply in various ways. So, It is served in web 2.0 environment actively. But, in the mashup service, because generated multimedia contents linked with web map are new type of multimedia contents which include user's migration routes in the space such as GPS coordinates. Thus, there are no protection ways for intellectual property created by GIS web-map service users and user's privacy. In this paper, we proposed a location and user information hiding scheme for GIS web-map service. This scheme embeds location and user information into a picture that is taken by camera module on the mobile phone. It is not only protecting way for user's privacy but is also tracing way against illegal photographer who is peeping person through hidden camera. And than, we also realized proposed scheme on the mobile smart phone. For minimizing margin of error about location coordinate value against contents manipulating attacks, GPS information is embedded into chrominance signal of contents considering weight of each digit about binary type of GPS coordinate value. And for tracing illegal photographer, user information such as serial number of mobile phone, phone number and photographing date is embedded into frequency spectrum of contents luminance signal. In the experimental results, we confirmed that the error of extracted information against various image processing attacks is within reliable tolerance. And after file format translation attack, we extracted embedded information from the attacked contents without no damage. Using similarity between extracted one and original templete, we also extracted whole information from damaged chrominance signal of contents by various image processing attacks.

• Journal of Korea Water Resources Association
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• v.46 no.1
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• pp.35-45
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• 2013

The aim of study is to present how to estimate and use the FRI (Flood Risk Index) for classifying area zones based on regional flooding risk in terms of the integrated flood risk management. To estimate the FRI at a spatial resolution of city/county/town units for the Nakdong River Watershed, the 17 representative flood indexing factors are carefully selected for the three flood indexes, such as PI (Pressure Index), SI (State Index), and RI (Response Index) under the P-S-R (Pressure-State-Response) classification system. Because flood indexing factors are measured at different scales and units, they are transformed into a common domain by the T-Score normalization technique. The entropy weight coefficient method is also applied to calculate the weight of flood indexing factors in order to reduce subjective judgement on the effect of weight coefficients. The three flood indexes of PI, SI, and RI are integrated for an overall value of the FRI to evaluate the flood risk of districts. To examine the practical application of the proposed FRI, the FRI results with/without the weight coefficients are compared with flooding zones of natural disaster risk areas officially announced in 2010. It is expected that the FRI ensured by full verification can make regional protection plans against flooding disasters with respect to causes and characteristics of past floods.

• Journal of the Korean Society of Radiology
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• v.3 no.1
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• pp.17-21
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• 2009

The Recently, large area matrix-addressed image detectors are investigated for X-ray imaging with medical diagnostic and other applications. In this paper, a new flat panel gas detector for diagnostic X-ray imaging is proposed, and its characteristics are investigated. The research of flat panel gas detector is not exist at all. Because of difficulty to inject gas against to atmospheric pressure. So almost gas detector made by chamber shape. We made flat panel sample by display technique. (ex: PDP, Fed, etc.) The experimental measurements, the transparent electrodes, dielectric layer, and the MgO protection layer were formed in front glass. And, the X-ray phosphor layer and address electrodes are formed in the rare glass. The dark current, the x-ray sensitivity and linearity as a function of electric field were measured to investigate the electrical properties. From the results, the stabilized dark current density and the significant x-ray sensitivity were obtained. And the good linearity as a function of exposure dose was showed in wide diagnostic energy range. These results means that the passive matrix-addressed flat panel gas detector can be used for digital x-ray imaging.

• Journal of Chest Surgery
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• v.44 no.3
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• pp.215-219
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• 2011

Background: Selective antegrade perfusion via axillary artery cannulation along with circulatory arrest under deep hypothermia has became a recent trend for performing surgery on the ascending aorta and aortic arch and when direct aortic cannulation is not feasible. The authors of this study tried using moderate hypothermia with right brachial and femoral artery perfusion to complement the pitfalls of single axillary artery cannulation and deep hypothermia. Materials and Methods: A retrospective analysis was performed on 36 patients who received ascending aorta or aortic arch replacement between July 2005 and May 2010. The adverse outcomes included operative mortality, permanent neurologic dysfunction and temporary neurologic dysfunction. Results: Of these 36 patients, 32 (88%) were treated as emergencies. The mean age of the patients was 61.9 years (ranging from 29 to 79 years) and there were 19 males and 17 females. The principal diagnoses for the operation were acute type A aortic dissection (31, 86%) and aneurysmal disease without aortic dissection (5, 14%). The performed operations were ascending aorta replacement (9, 25%), ascending aorta and hemiarch replacement (13, 36%), ascending aorta and total arch replacement (13, 36%) and total arch replacement only (1, 3%). The mean cardiopulmonary bypass time was $209.4{\pm}85.1$ minutes, and the circulatory arrest with selective antegrade perfusion time was $36.1{\pm}24.2$ minutes. The lowest core temperature was $24{\pm}2.1^{\circ}C$. There were five deaths within 30 post-op days (mortality: 13.8%). Two patients (5.5%) had minor neurologic dysfunction and six patients, including three patients who had preoperative cerebral infarction or unconsciousness, had major neurologic dysfunction (16.6%). Conclusion: When direct aortic cannulation is not feasible for ascending aorta and aortic arch replacement, the right brachial and femoral artery can be used as arterial perfusion routes with the patient under moderate hypothermia. This technique resulted in acceptable outcomes.

• Korean Journal of Environmental Agriculture
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• v.36 no.4
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• pp.241-248
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• 2017

BACKGROUND: RNA interference (RNAi) eliminates or decreases gene expression by disrupting the target mRNA or by interfering with translation. Recently, RNAi technique was applied to generate new crop traits which provide protection against pests. To establish the environmental risk assessment protocol of RNAi LMO in lab scale, we developed dsRNA expression system using E. coli and tested acute oral toxicity assay to honey. METHOD AND RESULTS: The dsRNA expression vector, L4440, was chosen and cloned 240 bp of Snf7 and GFP gene fragment. To develop the maximum dsRNA induction condition in E. coli, we tested induction time, temperature and IPTG concentration in media. To estimate the risk assessment of dsRNA to honey bee, it has been selected and cultured with dsRNA supplement for 48 hours according to OECD guideline. As a result, the optimum condition of dsRNA induction was $37^{\circ}C$, 4 hours and 0.4 mM IPTG concentration and the difference between Snf7 and GFP dsRNA molecules from E. coli was not significant in survival and behavior to honey bee. Furthermore, blast search results indicated that effective match of predicted dsRNA fragments were not existed in honey bee genome. CONCLUSION: In this study, we developed and tested the acute oral toxicity of dsRNA using E. coli expression system to honey bee.

• Korean Business Review
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• v.18 no.1
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• pp.59-79
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• 2005

recently, world is progressing large quantity consumption with continuous Innovation and economic growth and pollution is accelerated at these process. Increase of industry activity and service that is point of corporation activity is discharging environmental pollutants at whole process to manufacture of end product and exhaust process from acquisition of raw material for accompanied product production hereupon. At the same time, being promoting resources consumption by that use much raw material, As a result, is becoming obstacle factors in sustainable development. So, corporation's responsibility for environmental protection is emphasized. Corporation which must prepare in green round or environmental problems should consider environmental effects that is happened over whole life of products that include waste treatment after raw material acquisition and use as well as selling end product simply. A Life Cycle Assessment techniques is normalized and standardized in International Standard Organization for technical committee 207(TC 207) world widely, and effort to apply in corporation's activity because mastering LCA techniques in domestic several corporations is undergone actively. Coming into effect of Kyoto's Protocol and International Organization for Standard 14000 series revision are presenting new survival principle in competition between country or corporation. LCA technique may become very useful means to corporation which wish to attempt environment management in real condition that awareness for environment is important. Also, An LCA to each product is going to cause big effects in corporation's whole image as well as competitive power raising for single product. Therefore, this research wishes to examine some instances for the future competitive product development at the estimation of environmental friendliness using LCA techniques and more theoretical considerations of the LCA techniques that can dominate corporation's fate.

• Journal of Forest and Environmental Science
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• v.13 no.1
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• pp.153-165
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• 1997

Hydroxyl radicals were detected and their qualitative yields were estimated by using chemiluminescence method and $\gamma$-irradiation technique in oxygen or chlorine dioxide radicals bleaching conditions. The correlation of hydroxyl radical formation and lignin model(Apocynol) or carbohydrate model($\alpha$-D-glucopyranose and methyl-$\beta$-D-glucopyranoside) degradation was studied in the presence of metal ion or without metal ion. The results showed that the presence of metal ions efficiently affected the formation of hydroxyl radicals in oxygen bleaching process, in the order of $Cu^{2+}$ > $Mn^{2+}$ > $Mg^{2+}$ > $Fe^{2+}$, and these metal gave also rise to the degradation of carbohydrate. But it was found that the addition of $100{\mu}m\;Mg^{2+}$ gave an efficient protection against carbohydrate degradation and suppressed the hydroxyl radical formation under oxygen bleaching conditions. And the presence of $Cu^{2+}$ had a detrimental effect on the stability of carbohydrates, whereas the addition of $3{\mu}m\;Mn^{2+}$ surprisingly had a small protective effect on methyl--$\beta$-D-glucopyranoside. In the $ClO_2$ radical bleaching conditions the hydroxyl radical expected to generate from water or substrates was not detected in the presence of metals.

• Journal of the Korean Geosynthetics Society
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• v.6 no.1
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• pp.9-16
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• 2007

Geotextile is one of the most useful and effective polymer material in civil construction works and the main function of geotextile is separation, reinforcement, filtering and drainage. Recently, because of the shortage of natural rock, traditional forms of river and coastal structures have become very expensive to build and maintain. Therefore, the materials used in hydraulic and coastal structures are changing from the traditional rubble and concrete systems to the cheaper materials and systems. One of these alternatives employs geotextile tube technology in the construction of coastal and shore protection structures, such as embankment, see dyke, groins, jetties, detached breakwaters and so on. Geotextile tube technology has changed from being an alternative construction technique and, in fact, has advanced to become the most effective solution of choice. This paper presents case history of sea dyke filter construction using geotextile tube mattress and also, various issues related to the tube mattress design and construction technology.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.44 no.7 s.361
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• pp.71-80
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• 2007

This paper describes an efficient hardware design of WiBro security processor (WBSec) supporting for the security sub-layer of WiBro wireless internet system. The WBSec processor, which is based on AES (Advanced Encryption Standard) block cipher algorithm, performs data oncryption/decryption, authentication/integrity, and key encryption/decryption for packet data protection of wireless network. It carries out the modes of ECB, CTR, CBC, CCM and key wrap/unwrap with two AES cores working in parallel. In order to achieve an area-efficient implementation, two design techniques are considered; First, round transformation block within AES core is designed using a shared structure for encryption/decryption. Secondly, SubByte/InvSubByte blocks that require the largest hardware in AES core are implemented using field transformation technique. It results that the gate count of WBSec is reduced by about 25% compared with conventional LUT (Look-Up Table)-based design. The WBSec processor designed in Verilog-HDL has about 22,350 gates, and the estimated throughput is about 16-Mbps at key wrap mode and maximum 213-Mbps at CCM mode, thus it can be used for hardware design of WiBro security system.