• Journal of Advanced Navigation Technology
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• v.25 no.6
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• pp.441-449
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• 2021

With advances in autonomous vehicles, there is a growing demand for more accurate position estimation. Especially, this is a case for a moving robot for the indoor operation which necessitates the higher accuracy in position estimation when the robot is required to execute the task at a predestined location. Thus, a method for improving the position estimation which is applicable to both the fixed and the moving object is proposed. The proposed method exploits the initial position estimation from Bluetooth beacon signals as observation signals. Then, it estimates the gravitational acceleration applied to each axis in an inertial frame coordinate through computing roll and pitch angles and combining them with magnetometer measurements to compute yaw angle. Finally, it refines the control inputs for an object with motion dynamics by computing acceleration on each axis, which is used for improving the performance of Kalman filter. The experimental assessment of the proposed algorithm shows that it improves the position estimation accuracy in comparison to a conventional Kalman filter in terms of average error distance at both the fixed and moving states.

• Applied Chemistry for Engineering
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• v.18 no.6
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• pp.618-624
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• 2007

thermochemical methane reforming consisting of two steps on Cu/Fe/Zr mixed oxide media was carried out using a fixed bed infrared reactor. In the first step, the metal oxide was reduced with methane to produce CO, $H_2$ and the reduced metal oxide in the temperature of 1173 K. In the second step, the reduced metal oxide was re-oxidized with steam to produce $H_2$ and the metal oxide in the temperature of 973 K. The reaction characteristics on the added amounts of Cu in Cu/Fe/Zr mixed oxide media and the cyclic tests were evaluated. With the increase of the added amount of Cu in Cu/Fe/Zr mixed oxide media, the conversion of $CH_4$, the selectivity of $CO_2$ and the $H_2/CO$ molar ratio were increased, while the selectivity of CO was decreased in the first step. On the other hand, the evolved amount of $H_2$ was decreased with increasing the added amount of Cu in the second step. The $Cu_xFe_{3-x}O_4/ZrO_2$ medium added with Cu of x = 0.7 showed good regeneration properties in the 10th cyclic tests indicating that the medium had high durability. In addition, the gasification of the deposited carbon in the water splitting step was promoted with the addition of Cu in the media.

• Korean journal of communication and information
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• v.63
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• pp.5-25
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• 2013

Korean society suffers from severe divisions represented by bi-polarization and collapse of the middle class. Intensive demanding on expanding social welfare budget has emerged in accordance with such a dramatic shift. Social consensus moving toward well-financed welfare policy, however, happens to meet political opposition supported by the discourse of fiscal soundness. This paper thus pays particular attention to deciphering the discursive structure in way of understanding how discourses bring public policy into play. For this purpose, news articles about fiscal soundness collected from 8 national newspapers have been analyzed in terms of frame, attitude, perspective and world view. Research results show, first of all, that there exist persistent competition between two frames identified as 'reduced tax with fiscal discipline' and 'increased tax with welfare money.' While the 'reduced tax' frame favors in maintaining tax cut at the expense of welfare budjet, the frame of 'increased tax' supports such arguments as the flexible employment of fiscal soundness and prosperity of national community helped by widening tax revenues. Also did these frames include a number of sub-frames like welfare populism, partisan politics, trickle down effect, tax bonanza for the rich, universal welfare and market over-reactions in order to bolster its logical authority. Media's active taking a part in penetrating supportive frames in line with political stance was found as well. Taking into account both the discursive structure upheld by frames and politics materialized by the media, the authors argue that public policies should be considered more as discourse than fixed reality. Shedding additional light on understanding the interplay among public opinion, policies and media discourse is of another importance for further study.

• Journal of the Korean Magnetics Society
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• v.9 no.4
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• pp.203-209
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• 1999

Effects of Mo and Si addition in Cr underlayer on magnetic properties of CoCrTa/CrMo and CoCrTa/Si thin films media were investigated. Thin films were prepared with DC magnetron sputtering system. The thickness of CoCrTa magnetic layer and Cr underlayer were fixed at 300 $\AA$ and 700 $\AA$, respectively. The substrate heating temperature was kept constant at 26$0^{\circ}C$ for both magnetic layer and underlayer preparation. The coercivity increase of CoCrTa film was realized due to Mo addition in Cr underlayer. Si addition made a small decrease in coercivity. Coercivity increase seems to be attributed by the improvement of preferred orientation of Cr(200) plane. It is found that lattice fit between Cr(200) and CoCrTa(1120) of CrMo underlayer is better than that of CrSi underlayer. This small misfit may also contribute coercivity increase.

• Journal of Science of Art and Design
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• v.1
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• pp.165-188
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• 1999

When we think about visual art, we can't pass over the matter of images and spaces. An image is fixed in a painting space. If the image were posited in the river of time, it would be changed as time flowed on. Its image might be created, rigged, transfigured or it might vanish or remain as traces. The image is changed through the process of expressing them on the painting surfaces. In paintings the changing of the image is caused not only by working processes but also recognizing the objects. In modernist painting, the idea of space was important, but in postmodernist view, the idea of time becomes essential. In this thesis I will focus on the matter of time and image of painting in the late 20th century. Studying the relationship of image and time is not familiar because we had considered the space as being more related to painting distinction than time. Presently, the concept of space can't be divided from that of time. In Physics, they recently called it as a united concept- time-space. Painting space also becomes one asking and recieve the concept of time actively. Now in painting, time is no more a supporting matter but becomes a major matter. In the late 20th century, we can find many trials to catch the change of images as time flowes on and express them as a trace through using verioty media. One of the way to drawing the change of images as time passes could be seen through various joint images in one painting space and another in the traces of one image. The other could be done by using new media such as computer in the example of fractal art. It shows the images chainging of practically as time changes. New understanding about time of this era has to be affirmatively accepted because it reflects the contemporary cultural situation and in art, the concern about the possiblity of it and finding new medias which has to go on.

• Journal of KIISE:Computing Practices and Letters
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• v.10 no.1
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• pp.114-124
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• 2004

In this paper, we present an automatic C source code generation system for DirectShow based multimedia application programming. In this system, C source code is automatically synthesized from the filter connection graph edited with GraphEdit, a utility tool provided with DirectShow SDK package from Microsoft. In traditional DirectShow programming environments, program design and brief testing steps are usually done with GraphEdit tool just by inserting filters and connecting them properly, while actual implementation of the program should be done separately. The filter connection graph information from GraphEdit is used just as a reference in such the implementation step. Therefore, our system which automatically generates C source code directly from the filter connection graph of GraphEdit seems very useful and many programmers can develop DirectShow based multimedia application programs more effectively and quickly using our system. In addition, our system supports more various media stream control functions for the generated application programs than the existing system such as Wizard which supports limited and fixed number of media control functions only. This feature allows more flexibility in the user interface of the generated source program and makes our system more practical for DirectShow based programming.

• Broadcasting and Media Magazine
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• v.15 no.1
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• pp.24-36
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• 2010

Nowadays, digital broadcasting providers have plan to extend their service area to 3D broadcasting without exchanging conventional system and equipments. The maintenance of backward compatibility to conventional 2D broadcasting system is very importance issue on digital broadcasting. To satisfy the requirement, highly-optimized MPEG-2 video encoder is essential for coding left-view and new video coding techniques having higher performance than MPEG-4 AVC/H.264 is needed for right-view since terrestrial broadcasting system has very limited and fixed bandwidth. In this paper, conventional video coding algorithms and new video coding algorithms are analyzed to present a capable solution for the best quality stereoscopic 3D broadcasting keeping backward compatibility within the bandwidth.

• The Journal of the Korea Contents Association
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• v.9 no.2
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• pp.181-192
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• 2009

Prints in the contemporary art has the radical aspects at not only to maintain the characteristic of printmaking in a field of visual image but also to fulfill and communicate a desire of the public. We can see this from the change of the printmaking forms among the alternation of diverse expression methods and media such as from the line-cut at the Renaissance to colored print process, photography, the beginning of 20th century cartoons, advertisement, art, and graphic poster. From that, we can understand the printmaking as a fluid media, not fixed, has finely accomplished its functions as an act of visual language to smoothly communicate with the individual desire and character than word or language at the complex and various cultural surface. This study is focused on that prints as an avant-garde language in popular culture. Therefore, I have examined the following two aspects. First, with focussing at the specific characters of the graphic posters, I try to define the differences between language and visual language and the effect from it to our emotional perception and behavior with the politic and economic point of view. Second, how has the printmaking art as an fine arts finely accomplished an linguistic action. These are the purpose of this study.

• Journal of Microbiology and Biotechnology
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• v.21 no.10
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• pp.1073-1080
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• 2011

In order to investigate and generalize the effects of carbon and nitrogen sources on the growth of and lipid production in Chlorella sp. 227, several nutritional combinations consisting of different carbon and nitrogen sources and concentrations were given to the media for cultivation of Chlorella sp. 227, respectively. The growth rate and lipid content were affected largely by concentration rather than by sources. The maximum specific growth was negatively affected by low concentrations of carbon and nitrogen. There is a maximum allowable inorganic carbon concentration (less than 500~1,000 mM bicarbonate) in autotrophic culture, but the maximum lipid content per gram dry cell weight (g DCW) was little affected by the concentration of inorganic carbon within the concentration. The lipid content per g DCW was increased when the microalga was cultured with the addition of glucose and bicarbonate (mixotrophic) at a fixed nitrogen concentration and with the lowest nitrogen concentration (0.2 mM), relatively. Considering that lipid contents per g DCW increased in those conditions, it suggests that a high ratio of carbon to nitrogen in culture media promotes lipid accumulation in the cells. Interestingly, a significant increase of the oleic acid amount to total fatty acids was observed in those conditions. These results showed the possibility to induce lipid production of high quality and content per g DCW by modifying the cultivation conditions.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.40 no.7
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• pp.261-272
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• 2003

An Ethernet PON(Passive Optical Network) is an economical and efficient access network that has received significant research attention in recent years. A MAC(Media Access Control) protocol of PON , the next generation access network, is based on TDMA(Time Division Multiple Access) basically and can classify this protocol into a fixed length slot assignment method suitable for leased line supporting QoS(Quality of Service) and a variable length slot assignment method suitable for LAN/MAN with the best effort. For analyzing the performance of these protocols, we design an Ethernet PON model using OPNET tool. To establish the maximum efficiency of a network, we verify a MAC protocol and determine the optimal number of ONUs(Optical Network Unit) that can be accepted by one OLT(Optical Line Terminal) and propose the suitable buffer size of ONU based on analyzing the end-to-end Ethernet delay, queuing delay, throughput, and utilization.