• Journal of the Korea institute for structural maintenance and inspection
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• v.19 no.6
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• pp.72-79
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• 2015

An efficient and practical reliability evaluation method is proposed for the coastal structures in this paper. It is capable of evaluating reliability of real complicated coastal structures considering uncertainties in various sources of design parameters, such as wave and current loads, resistance-related design variables including Young's modulus and compressive strength of the reinforced concrete, soil parameters, and boundary conditions. It is developed by intelligently integrating the Latin Hypercube sampling (LHS), Monte Carlo simulation (MCS) and the finite element method (FEM). The LHS-based MCS is used to significantly reduce the computational effort by limiting the number of simulation cycles required for the reliability evaluation. The applicability and efficiency of the proposed method were verified using a caisson-type breakwater structure in the numerical example.

• Journal of the Society of Naval Architects of Korea
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• v.38 no.4
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• pp.39-47
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• 2001

In this paper, the hydroelastic behavior of a mat-type large floating structure is analyzed in time domain by using mode superposition method. The time-memory function is estimated by Fourier transforming the wave damping coefficients, which are computed by a higher-order boundary element method based on potential theory. Meanwhile, the structural response is obtained by time integrating the eigenmodes of the structure. Numerical examples are made for three test cases on the scaled model of a mat-type large floating structure ; weight pull-up case, weight drop case and weight moving case. In all three cases, the numerical results coincide well with experimental data.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.39 no.6
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• pp.11-23
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• 2002

Computational models up to now for Korean morphology have been linear in that it deal with only segmentation of morphemes rather than formation of the internal structure of a word. When integrating a linear computational model with syntax analysis, it requires an additional interface component between this model and the syntax to bind morphemes into sentence constituents. Furthermore the linear model is not semantically intuitive. In this paper, based on word-syntactical viewpoint, we propose an integrated computational model that deals with morpheme segmentation, formation of syntactic element (sentence constituent), and even internal structure of word. Formalism of two-level morphology is employed to cope with morpheme segmentation and alternation problems, and functional diacritics are proposed to incorporate categorial context into the two-level formalism. A modified GLR-based algorithm is also proposed to check syntactical constraint of morphemes.

• Korean Journal of Construction Engineering and Management
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• v.18 no.3
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• pp.42-51
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• 2017

Measuring and evaluating project progress and performance are the key element of the construction project success. Construction progress is typically measured quantitatively by evaluating cost and time allocated to the project deliverable, and thus properly integrating cost and time is essential to the project management. This research was performed to propose an alternative methodology to integrate the cost and time and provide a framework for the progress measurement. The researchers developed a typical work process for the cost and schedule planning and also developed an alternative cost-schedule integration method by using progress integration units (PIU). A discipline of a construction phase served as a common level for WBS and CBS integration, so the PIUs'were defined under discipline. A case study project was selected to validate the developed methodology. The result showed the proposed method improved efficiency of cost and time integration. The result also showed the excluding material for the progress measurement purpose significantly reduced the bias of progress measurement.

• Journal of Digital Convergence
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• v.11 no.11
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• pp.747-751
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• 2013

Researches on U-Healthcare service integrating medical information and IT technologies are actively conducted. U-Healthcare service is the next generation's medical paradigm that ensures conveniences to many users so that the society recognizes the importance and attempts for commercialization through various business model are performed. To form such U-Healthcare service market safely, various policies on the social structure should be established through the standard and the medical law to systemize of the medical information led by the governmen. Especially, the government's security policy to ensure the safety for the government leading visualization of U-Healthcare should be firmly established. Firstly, this paper presents U-healthcare Service and policy guideline. Secondly, it analyzes security threatening factors for the safe U-Healthcare service. By classifying the analyzed security threatening factors based on three major elements of the security, Confidentiality, Integrity and Availability of security policy for each element is proposed.

• Composites Research
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• v.12 no.2
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• pp.70-81
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• 1999

Resin transfer molding(RTM) as a composite manufacturing process is currently of great interest in the aerospace industry requiring high performance composite parts. In this study, an analysis of mold filling in the RTM process was carried out by numerical simulation using finite element/control volume technique. Experimental work for the visualization of resin flow through fibrous preform was also conducted in order to quantitatively measure the permeabilities of the fiber mats and to evaluate the validity of the developed numerical code. The different types of fiber mats and silicon oils were selected as reinforcements and resin materials, respectively. The effects of fibrous preform structure, mold geometry, and preplaced insert on the flow front patterns during mold filling were examined by integrating the model predictions and experimental results. The flow fronts predicted by numerical simulation were in good agreement with those observed experimentally. However, according to the regions of the mold, some deviations between predicted and observed flow fronts could be found because of non-uniform fiber volume fraction. Weldline locations for the resin flow through round insert preplaced in the mold could be qualitatively deduced based on predicted flow fronts.

• Archives of design research
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• no.16
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• pp.185-196
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• 1996

The series of ‘Dubonnet’poster is one of the masterpieces of Cassandre who was the leader of advertising poster in 1920's and 1930's. Orihinally it was a triptych, but it was developed as a serial work later through lettering and seasonal advertising posters. It was kept in circulation for more than two decades and issued in a variety of formats. In this thesis I tried to figure out the artistic character and uniqueness of Cassandre's poster by analyzing it with many different points of view of the poster, the stream of changing style and influence from the Avant-garde painting. In chapterII, objectively analyzing the series of‘Dubonnet’one by one, I examined the method that Cassandre used to deliver the concept of advertising and his message. The triptych, the first one of series of Dubonnet poster is witty, the slogan is a pun using the words dubo(doubt), bon(good), and Dubonnet, and the theme is treated as an animated sequence in the manner of a comic strip. In the following winter and summer seasonal advertising posters, the‘Dubonnet man’in the same position is enjoying the‘Dubonnet’, irrespective of the hazards of climate and season, There was a change towards 1929 that rectilinear design gave place to supple and undulating lines in Cassandre's posters. Seasonal advertising posters also showed the change, and the tendency of realistic and concrete elements of an expression was strengthened. In chapterIII, I studied three as main characters of Cassandre's poster. The first one is simple and geometric expression, second one is uniqueness of figures and the last one is important roll of lettering. Cassandre believed that there were fundamental differences between the function of a poster and that of a painting. He also recognized that the symbol was the essential element in the poster design, which would be simply and swiftly recognized. The recognition led him to simple design and bold geometric abstraction. He was a man who knew the value of copy in advertising and developed it fully in his simplified geometric compositions by integrating of letterforms and image. The‘Dubonnet man’is geometrized, almost featureless. This approach of rendering human beings was one that Cassandre had used from the early years, most notably in his posters for Dubonnet.

• Journal of Power Electronics
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• v.19 no.6
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• pp.1366-1379
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• 2019

High-gain DC/DC converters have become one of the key technologies for the grid-connected operation of new energy power generation, and its research provides a significant impetus for the rapid development of new energy power generation. Inspired by the transformer effect and the ripple-suppressed ability of a coupled inductor, a double-coupled inductor high gain DC/DC converter with a ripple absorption circuit is proposed in this paper. By integrating the diode-capacitor voltage multiplying unit into the quadratic Boost converter and assembling the independent inductor into the magnetic core of structure coupled inductors, the adjustable range of the voltage gain can be effectively extended and the limit on duty ratio can be avoided. In addition, the volume of the magnetic element can be reduced. Very small ripples of input current can be obtained by the ripple absorption circuit, which is composed of an auxiliary inductor and a capacitor. The leakage inductance loss can be recovered to the load in a switching period, and the switching-off voltage spikes caused by leakage inductance can be suppressed by absorption in the diode-capacitor voltage multiplying unit. On the basis of the theoretical analysis, the feasibility of the proposed converter is verified by test results obtained by simulations and an experimental prototype.

• Earthquakes and Structures
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• v.10 no.1
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• pp.53-71
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• 2016

Unconventional computer vision and image processing techniques offer significant advantages for experimental applications to shaking table testing, as they allow the overcoming of most typical problems of traditional sensors, such as encumbrance, limitations in the number of devices, range restrictions and risk of damage of the instruments in case of specimen failure. In this study, a 3D motion optical system was applied to analyze shake table tests carried out, up to failure, on a natural-scale masonry structure retrofitted with steel reinforced grout (SRG). The system makes use of wireless passive spherical retro-reflecting markers positioned on several points of the specimen, whose spatial displacements are recorded by near-infrared digital cameras. Analyses in the time domain allowed the monitoring of the deformations of the wall and of crack development through a displacement data processing (DDP) procedure implemented ad hoc. Fundamental frequencies and modal shapes were calculated in the frequency domain through an integrated methodology of experimental/operational modal analysis (EMA/OMA) techniques with 3D finite element analysis (FEA). Meaningful information on the structural response (e.g., displacements, damage development, and dynamic properties) were obtained, profitably integrating the results from conventional measurements. Furthermore, the comparison between 3D motion system and traditional instruments (i.e., displacement transducers and accelerometers) permitted a mutual validation of both experimental data and measurement methods.

• Journal of the Korean Chemical Society
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• v.65 no.5
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• pp.370-381
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• 2021

This study compared and analyzed the chemistry curriculum of South Korea and Singapore. The analysis revealed that Korea's achievement standards in the chemistry subject comprised knowledge and skills, whereas Singapore's achievement standards comprised knowledge, skills, values, and attitudes. The scope of knowledge and skills of the Singaporean achievement standards-wherein each element was explicitly presented-were more extensive than that of Korea. The elementary school curriculum in both countries was structured to help students qualitatively understand materials in real life, whereas the middle school content was structured such that students could understand the topic of particles. Additionally, several differences were found in specific content elements; for example, the periodic tables were included only in the Singaporean content, whereas changes in the volume of gas according to temperature and pressure were included only in the Korean content. The Singaporean academic achievement standards, integrating knowledge, skills, values, and attitudes in science curriculum, can be used as a reference for adjusting and restructuring the Korean curriculum.