• International Journal of Concrete Structures and Materials
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• v.11 no.1
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• pp.135-149
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• 2017

The prediction of the actual ultimate capacity of confined concrete columns requires partial confinement utilization under eccentric loading. This is attributed to the reduction in compression zone compared to columns under pure axial compression. Modern codes and standards are introducing the need to perform extreme event analysis under static loads. There has been a number of studies that focused on the analysis and testing of concentric columns. On the other hand, the augmentation of compressive strength due to partial confinement has not been treated before. The higher eccentricity causes smaller confined concrete region in compression yielding smaller increase in strength of concrete. Accordingly, the ultimate eccentric confined strength is gradually reduced from the fully confined value $f_{cc}$ (at zero eccentricity) to the unconfined value $f^{\prime}_c$ (at infinite eccentricity) as a function of the ratio of compression area to total area of each eccentricity. This approach is used to implement an adaptive Mander model for analyzing eccentrically loaded columns. Generalization of the 3D moment of area approach is implemented based on proportional loading, fiber model and the secant stiffness approach, in an incremental-iterative numerical procedure to achieve the equilibrium path of $P-{\varepsilon}$ and $M-{\varphi}$ response up to failure. This numerical analysis is adapted to assess the confining effect in rectangular columns confined with conventional lateral steel. This analysis is validated against experimental data found in the literature showing good correlation to the partial confinement model while rendering the full confinement treatment unsafe.

• International Commerce and Information Review
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• v.16 no.2
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• pp.89-109
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• 2014

The purpose of price escalation clauses has the effect of increasing the L/C value subject to external pricing mechanisms. This will be found inter alia in metals and oil products transactions. Such a clause gives rise to a question. That is, whether it is enforceable or whether it constitutes a letter of credit. The problem is what to reference to a source outside the context of a letter of credit constitutes a non-documentary condition rendering the undertaking something other than a letter of credit. Reference to an objective and readily available index is not something that renders the undertaking obscure and is not "non-documentary in the sense that it is possible to make an objective verification of the data. The possible solution is that not every non-documentary condition will be disregarded. For example, an index specified in the credit will not be disregarded as stipulated in ISP98 and URDG758. If a non-documentary is "central and fundamental", it seems that the parties intended a dependent payment obligations. The most common means of overcoming this conflicts of interests is to issue an instrument incorporatingan escalation clause, but capping the bank's maximum payment obligation.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.6 no.5
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• pp.747-754
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• 2002

We propose a Web-based collaborative CAD system which is independent from any platforms, and develop a 3D solid modeler in the system. We developed a new prototype of 3D solid modeler based on the web using Java 3D API, which could be executed without any 3D graphics software and worked collaboratively interacting with each user. The modeler can create primitive objects and get various 3D objects by using loader. The interactive control is available to manipulate-objects such as picking, translating, rotating, zooming. Users connect to this solid modeler and they can create 3D objects and modify them as they want. When this solid modeler is imported to collaborative design system, it will be proved its real worth in today's CAD system. Moreover, if we improve this solid modeler adding to the 3D graphic features such as rendering and animation, it will be able to support more detail design and effect view.

• Journal of Korea Society of Industrial Information Systems
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• v.13 no.1
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• pp.11-21
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• 2008

Recently, it has shown an increased interest in 3D stereoscopic contents due to the development of the digital image media. Therefore, many techniques in 3D stereoscopic image generation have being researched and developed. However, it is difficult to generate high immersion and natural 3D stereoscopic contents, because the lack of 3D geometric information imposes restrictions in 2D image. In addition, control of the camera interval and rendering of the both eyes must be repetitively accomplished for the stereo effect being high. Therefore, we propose integrated editing system for 3D stereoscopic contents production using a variety of images. Then we generate 3D model from projective geometric information in single 2D image using image-based modeling method. And we offer real-time interactive 3D stereoscopic preview function for determining high immersion 3D stereo view. And then we generate intuitively 3D stereoscopic contents of high-quality through a stereoscopic LCD monitor and a polarizing filter glasses.

• Journal of Korea Multimedia Society
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• v.12 no.8
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• pp.1055-1065
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• 2009

High-dynamic-range (HDR) rendering technology changes the range from the broad dynamic range (up to 9 log units) of a luminance, in a real-world scene, to the 8-bit dynamic range which is the common output of a display's dynamic range. One of the techniques, iCAM06 has a superior capacity for making HDR images. iCAM06 is capable of making color appearance predictions of HDR images based on CIECAM02 and incorporating spatial process models in the human visual system (HVS) for contrast enhancement. However there are several problems in the iCAM06, including obscure user controllable factors to be decided. These factors have a serious effect on the output image but users get into difficulty in that they can't find an adequate solution on how to adjust. So a suggested model gives a quantitative formulation for user controllable factors of iCAM06 to find suitable values which corresponds with different viewing conditions, and improves subjective visuality of displayed images for varying illuminations.

• Journal of the Korea Institute of Building Construction
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• v.24 no.1
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• pp.67-75
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• 2024

In the context of Korean residential heating systems, Ondol pipelines are a prevalent choice. However, the maintenance of these pipelines becomes a complex task once they are embedded within concrete structures. As time progresses, the accumulation of sludge, corrosive oxides, and microorganisms on the inner surfaces of these pipelines diminishes their heating efficiency. In extreme scenarios, this accumulation can induce corrosion and scale formation, compromising the system's integrity. Consequently, this research introduces an ultrasonic generation system tailored for the upkeep of Ondol pipelines, with the objective of empirically assessing its practicality. This investigation delineates three variants of ultrasonic generating apparatuses: those employing surface vibration, external generation, and internal generation techniques. To emulate the presence of contaminants within the pipelines, substances in powder, slurry, and liquid forms were employed. The efficacy of the cleaning process post-ultrasonic wave application was scrutinized over time, with image analysis methodologies being utilized to evaluate the outcomes. The findings indicate that ultrasonic waves, whether generated externally or internally, exert a beneficial effect on the cleanliness of the pipelines. Given the inherent characteristics of Ondol pipelines, external generation proves impractical, thereby rendering internal generation a more viable solution for pipeline maintenance. It is anticipated that future endeavors will pave the way for innovative maintenance strategies for Ondol pipelines, particularly through the advancement of internal generation technologies for pipeline applications.

• Journal of Korean language education
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• v.28 no.1
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• pp.79-111
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• 2017

This study is a trend analysis study that discusses the current status and directions of research methods of KAP research. The existing trend ana lysis studies dealing with research methods have problems in that the classification criteria of the studies used are rough and different from each other, rendering comparison between studies being difficult, and do not comprehensively cover research methods of diversified KAP research. Therefore, this study examined the research methods of KAP research from a critical point of view and suggested a set of classification criteria and an analysis framework that can be used consistently in classification and analysis of future KAP research methods. Based on the theoretical background of second language studies and applied linguistics, this study revised and supplemented Brown (2015)'s research method types and selected 289 journals and theses/dissertations from 2012 to 2016 and classified them into a new analysis framework. The primary and secondary studies, which are the major categories, were 219 and 70, respectively, so it was confirmed that there were much more primary studies. The primary studies then were subdivided into 128 qualitative research studies, 142 survey research studies, and 23 quantitative research studies, pointing to the trend that survey and qualitative research methods were preferred. In the qualitative research approaches, there were 21 action research studies, which were used the most. In addition, such qualitative research approaches as case studies and narrative inquiries which were difficult to find in the past, have gradually increased, confirming that the diversification of research methods is becoming common. However, there were still many studies that did not explicitly put forward research questions and there were many studies that did not report reliability and effect sizes in quantitative research. Of the 23 quantitative studies, only 50% reported reliability, and only three reported effect sizes. In order to enable systematic reviews (meta-analysis) of quantitative research and expect quality improvement of research in future KAP research, reporting of quantitative research should be done more systematically. This study is meaningful in that a systematic and detailed analysis framework was proposed to classify various research methods in the future and that the problems and directions for improvement of the KAP research methods were discussed through the analysis of the research trend of the KAP studies for the last 5 years.

• The Journal of the Convergence on Culture Technology
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• v.7 no.4
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• pp.711-719
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• 2021

EBS has been producing numerous educational contents with traditional virtual studio production systems since the early 2000s and applied AR video production system in October 2020, twenty-years after. Although the basic concept of synthesizing graphic elements and actual image in real time by tracking camera movement and lens information is similar to the previous one but the newly applied AR video production system contains some of advanced technologies that are improved over the previous ones. Marker tracking technology that enables camera movement free and position tracking has been applied that can track the location stably, and the operating software has been applied with Unreal Engine, one of the representative graphic engines used in computer game production, therefore the system's rendering burden has been reduced, enabling high-quality and real-time graphic effects. This system is installed on a crane camera that is mainly used in a crane shot at the live broadcasting studio and applied for live broadcasting programs for children and some of the videos such as program introductions and quiz events that used to be expressed in 2D graphics were converted to 3D AR videos which has been enhanced. This paper covers the effect of introduction and application of the AR video production system on EBS content production and the future development direction and possibility.

• The Journal of the Convergence on Culture Technology
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• v.8 no.3
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• pp.313-321
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• 2022

As 5G is getting developed, people are getting interested in immersive content. Some predicts that immersive content may be implemented in real life such as holograms, which were only possible in movies. Holograms, which has been studied for a long time since Dennis Gabor published the basic theory in 1948, are constantly developing in a new direction with digital technology. It is developing from a traditional optical hologram, which is produced by recording the interference pattern of light to a computer generated hologram (CGH) and a digital hologram printer. In order to produce a hologram using a digital hologram printer, holographic element (Hogel) image must first be created using multi-view images. There are a method of directly photographing an actual image and a method of modeling an object using 3D graphic production tool and rendering the motion of a virtual camera to acquire a series of multi-view images. In this paper, we propose a new method of getting image, which is one of the visual effect, VFX, producing multi-view images using chroma key composition. We shoot on the green screen of actual object, suggest the overall workflow of composition with 3D computer graphic(CG) and explain the role of each step. We expected that it will be helpful in researching a new method of image acquisition in the future if all or part of the proposed workflow to be applied.

• Cartoon and Animation Studies
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• s.37
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• pp.491-508
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• 2014

As number of making 3D feature animation films is increasing, 3D production pipeline become more complicated and more artists are needed than before. Major studios in foreign countries, in burden of producing high quality films with limited amount of budget and time, have been handling such difficulties by hiring technical directors in each department such as animation, rigging, cloth hair, and effect. Technical director is new occupation which appears after trend of producing animation is changed from 2D to 3D. Importance of technical director is increasing in respect to studios' needs which are related to complication in production time, manpower, budget, and production pipeline. This research is based on the researcher's work experience as an animation TD at Walt Diseny Animation Studio and Sony Pictures Imageworks, interview with working professionals, and related books and thesis. It focuses on the role of animation technical director in Disney's 3D feature animation film from two perspectives, 'Designing Production Pipeline' and 'Analyzing Problem of Shot'. Animation technical directors design and test production pipeline so that they can detect and solve problems that may arise in production process as early as possible. They not only analyze numerous problems of characters or shots limited to animation department but also in other departments such as modeling, mapping, character rigging, cloth, hair, lighting, rendering, software development in order to support artists to complete their shots according to the production schedule. In accordance with recent trend of increasing number of 3D feature animation film production in South Korea and collaboration with foreign studios outside of South Korea, it is vital to train animation technical directors who can develop production pipeline, analyze various problems of shots and characters to escalate efficiency in production.