• International Journal of Advanced Culture Technology
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• v.3 no.1
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• pp.21-30
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• 2015

Ceramic foams are prepared as positive images corresponding to a plastic foam structure which exhibits high porosities (85-90%). This structure makes the ceramic foams attractive as a catalyst in a dry reforming process, because it could reduce a high pressure drop problem. This problem causes low mass and heat transfers in the process. Furthermore, the reactants would shortly contact to catalyst surface, thus low conversion could occur. Therefore, this research addressed the preparation of dry reforming catalysts using a sol-gel catalyst preparation via a polymeric sponge method. The specific objectives of this work are to investigate the effects of polymer foam structure (such as porosity, pore sizes, and cell characteristics) on a catalyst performance and to observe the influences of catalyst preparation parameters to yield a replica of the original structure of polymeric foam. To accomplish these objectives industrial waste foams, polyurethane (PU) and polyvinyl alcohol (PVA) foams, were used as a polymeric template. Results indicated that the porosity of the polyurethane and polyvinyl alcohol foams were about 99% and 97%. Their average cell sizes were approximate 200 and 50 micrometres, respectively. The cell characteristics of polymer foams exhibited the character of a high permeability material that can be able to dip with ceramic slurry, which was synthesized with various viscosities, during a catalyst preparation step. Next, morphology of ceramic foams was explored using scanning electron microscopy (SEM), and catalyst properties, such as; temperature profile of catalyst reduction, metal dispersion, and surface area, were also characterized by $H_2-TPR$ and $H_2-TPD$ techniques, and BET, respectively. From the results, it was found that metal-particle dispersion was relatively high about 5.89%, whereas the surface area of ceramic foam catalysts was $64.52m^2/g$. Finally, the catalytic behaviour toward hydrogen production through the dry reforming of methane using a fixed-bed reactor was evaluated under certain operating conditions. The approaches from this research provide a direction for further improvement of marketable environmental friendly catalyst production.

• Fire Science and Engineering
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• v.25 no.6
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• pp.89-97
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• 2011

This study is for evaluating the fire resistance performance (1~2 h) of the RC Structure void slab using the Lightweight Hollow Sphere, which can reduce the unnecessary dynamic part of removing the central concrete. For this experiment, we set up depth of concrete cover, live load, and span length as the factors. The result comes out with all the slabs under those conditions can ensure the goal fire resistance performance (120 min). And among these factors, the resisting capability changes more sensitively with the live load rather than the thickness of cover. And the shorter span length could assure the better the fire resistance performance. The result observing the character in high temperature of the Lightweight Hollow Sphere which does not used as existing RC structure slab, a delay section in temperature change is occurred due to the Glass Transition in $100^{\circ}C$. And heat transfer by conduction does not occur at lightweight hollow sphere because the polystyrene in EPS (Expanded Polystyrene) melts point in $185^{\circ}C$. Therefore temperature at lightweight hollow sphere is lower than the concrete and rebar.

• Journal of Life Science
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• v.26 no.8
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• pp.976-982
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• 2016

Seaweed has high growth rate, low land usage, high CO₂ absorption and no competition for food resources. Therefore, the use of lignin-free seaweed as a raw material is arising as a third generation biomass for bioethanol production. Various pretreatment techniques have been introduced to enhance the overall hydrolysis yield, and can be categorized into physical, chemical, biological, enzymatic or a combination. Thermal acid hydrolysis pretreatment is one of the most popular methods to attain high sugar yields from seaweed biomass for economic reasons. At thermal acid hydrolysis conditions, the 3,6-anhydro-galactose (AHG) from biomass could be converted to 5-hydroxymethylfurfural (HMF), which might inhibit the cell growth and decrease ethanol production. AHG is prone to decomposition into HMF, due to its acid-labile character, and subsequently into weak acids such as levulinic acid and formic acid. These inhibitors can retard yeast growth and reduce ethanol productivity during fermentation. Thus, the carbohydrates in seaweed require effective treatment methods to obtain a high concentration of monosaccharides and a low concentration of inhibitor HMF for ethanol fermentation. The efficiency of bioethanol production from the seaweed biomass hydrolysate is assessed by separate hydrolysis and fermentation (SHF). To improve the efficiency of the ethanol fermentation of mixed monosaccharides, the adaptation of yeast to high concentration of sugar could make simultaneous utilization of mixed monosaccharides for the production of ethanol from seaweed.

• Journal of KIISE:Software and Applications
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• v.34 no.7
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• pp.646-654
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• 2007

In recent years, the use of text inserted into TV contents has grown to provide viewers with better visual understanding. In this paper, video text is defined as superimposed text region located of the bottom of video. Video text extraction is the first step for video information retrieval and video indexing. Most of video text detection and extraction methods in the previous work are based on text color, contrast between text and background, edge, character filter, and so on. However, the video text extraction has big problems due to low resolution of video and complex background. To solve these problems, we propose a method to extract text from videos using the Harris corner detector. The proposed algorithm consists of four steps: corer map generation using the Harris corner detector, extraction of text candidates considering density of comers, text region determination using labeling, and post-processing. The proposed algorithm is language independent and can be applied to texts with various colors. Text region update between frames is also exploited to reduce the processing time. Experiments are performed on diverse videos to confirm the efficiency of the proposed method.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.1B
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• pp.83-90
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• 2009

This study describes the characteristics of distribution of lift-force acting under pier deck through physical experiment. The shape of peak wave pressure was sharp when compressed air existed but was not sharp without that. Values of lift-force was different between edge point and center point in the same block. Distribution of lift-force was expressed differently owing to dimensionless of deck length (l/L), wave steepness (H/L), clearance height per wave height (D/H). The dimensionless factor of D/H affected on the lift-force the clearance between still water surface and decks. This decided the maximum of lift-force. In the case of the same values of D/H, the lift-force are changed by the wave steepness (H/L). Because (D/H) become smaller as the wave steepness (H/L) is increased the height of decks must be decided with the condition which don't have the clearance with $D_{max}$ for the stable design of deck of pier. Effect of reducing lift force was greater in the on-shore than the off-shore according to compressed air existence. This researches points out that design of deck should retain compressed air in order to reduce wave lift force.

• Journal of the Korean Society of Marine Environment & Safety
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• v.29 no.4
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• pp.389-394
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• 2023

In recent years, use of machine automation is rising in the industry. Ships also obtain machine condition information from sensor as digital information. However, on ships, crew members regularly surveil the engine room to check the condition of equipment and their information through analog gauges. This is a time-consuming and tedious process and poses safety risks to the crew while on surveillance. To address this, engine room surveillance using an autonomous mobile robot is being actively explored as a solution because it can reduce time, costs, and the safety risks for crew. Analog gauge reading using an autonomous mobile robot requires digitization for the robot to recognize the gauge value. In this study, image processing techniques were applied to achieve this. Analog gauge images were subjected to image preprocessing to remove noise and highlight their features. The center point, indicator point, minimum value and maximum value of the analog gauge were detected through image processing. Through the straight line connecting these points, the angle from the minimum value to the maximum value and the angle from the minimum value to indicator point were obtained. The obtained angle is digitized as the value currently indicated by the analog gauge through a formula. It was confirmed from the experiments that the digitization of the analog gauge using image processing was successful, indicating the equivalent current value shown by the gauge. When applied to surveillance robots, this algorithm can minimize safety risks and time and opportunity costs of crew members for engine room surveillance.

• The Korean Journal of Air & Space Law and Policy
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• v.30 no.2
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• pp.469-497
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• 2015

In 2009 Iridium 33, a satellite owned by the American Iridium Communications Inc. and Kosmos-2251, a satellite owned by the Russian Space Forces, collided at a speed of 42,120 km/h and an altitude of 789 kilometers above the Taymyr Peninsula in Siberia. NASA estimated that the satellite collision had created approximately 1,000 pieces of debris larger than 10 centimeters, in addition to many smaller ones. By July 2011, the U.S. Space Surveillance Network(SSN) had catalogued over 2,000 large debris fragments. On January 11, 2007 China conducted a test on its anti-satellite missile. A Chinese weather satellite, the FY-1C polar orbit satellite, was destroyed by the missile that was launched using a multistage solid-fuel. The test was unprecedented for having created a record amount of debris. At least 2,317 pieces of trackable size (i.e. of golf ball size or larger) and an estimated 150,000 particles were generated as a result. As far as the Space Treaties such as 1967 Outer Space Treaty, 1968 Rescue Agreement, 1972 Liability Convention, 1975 Registration Convention and 1979 Moon Agreement are concerned, few provisions addressing the space environment and debris in space can be found. In the early years of space exploration dating back to the late 1950s, the focus of international law was on the establishment of a basic set of rules on the activities undertaken by various states in outer space.. Consequently environmental issues, including those of space debris, did not receive the priority they deserve when international space law was originally drafted. As shown in the case of the 1978 "Cosmos 954 Incident" between Canada and USSR, the two parties settled it by the memorandum between two nations not by the Space Treaties to which they are parties. In 1994 the 66th conference of International Law Association(ILA) adopted "International Instrument on the Protection of the Environment from Damage Caused by Space Debris". The Inter-Agency Space Debris Coordination Committee(IADC) issued some guidelines for the space debris which were the basis of "the UN Space Debris Mitigation Guidelines" which had been approved by the Committee on the Peaceful Uses of Outer Space(COPUOS) in its 527th meeting. On December 21 2007 this guideline was approved by UNGA Resolution 62/217. The EU has proposed an "International Code of Conduct for Outer Space Activities" as a transparency and confidence-building measure. It was only in 2010 that the Scientific and Technical Subcommittee began considering as an agenda item the long-term sustainability of outer space. A Working Group on the Long-term Sustainability of Outer Space Activities was established, the objectives of which include identifying areas of concern for the long-term sustainability of outer space activities, proposing measures that could enhance sustainability, and producing voluntary guidelines to reduce risks to long-term sustainability. By this effort "Guidelines on the Long-term Sustainability of Outer Space Activities" are being under consideration. In the case of "Declaration of Legal Principles Governing the Activities of States in the Exp1oration and Use of Outer Space" adopted by UNGA Resolution 1962(XVIII), December 13 1963, the 9 principles proclaimed in that Declaration, although all of them incorporated in the Space Treaties, could be regarded as customary international law binding all states considering the time and opinio juris by the responses of the world. Although the soft law such as resolutions, guidelines are not binding law, there are some provisions which have a fundamentally norm-creating character and customary international law. In November 12 1974 UN General Assembly recalled through a Resolution 3232(XXIX) "Review of the role of International Court of Justice" that the development of international law may be reflected, inter alia, by the declarations and resolutions of the General Assembly which may to that extend be taken into consideration by the judgements of the International Court of Justice. We are expecting COPUOS which gave birth 5 Space Treaties that it could give us binding space debris mitigation measures to be implemented based on space debris mitigation soft law in the near future.

• The Korean Journal of Air & Space Law and Policy
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• v.27 no.2
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• pp.211-241
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• 2012

The Draft International Code of Conduct for Outer Space Activities officially proposed by the European Union on the occasion of the 55th Session of the United Nations Peaceful Uses of the Outer Space last June 2012 in Vienna, Austria is to fill the lacunae of the relevant norms to be applied to the human activities in the outer space and thus has the merit our attention. The missing elements of the norms span from the prohibition of an arms race, safety and security of the space objects including the measures to reduce the space debris to the exchange of information of space activities among space-faring nations. The EU's initiatives, when implemented, cover or will eventually prepare for the forum to deal with such issues of interests of the international community. The EU's initiatives begun at the end of 2008 included the unofficial contacts with major space powers including in particular the USA of which position is believed to have been reflected in the Draft with the aim to have it adopted in 2013. Although the Code is made up of soft law rather than hard law for the subscribing countries, the USA seems to be afraid of the eventuality whereby its strategic advantages in the outer space will be affected by the prohibiting norms, possibly to be pursued by the Code from its current non-binding character, of placing weapons in the outer space. It is with this trepidation that the USA has been opposing to the adoption of the United Nations Assembly Resolutions on the prevention of an arms race in the outer space (PAROS) and in the same context to the setting-up of a working group on the arms race in the outer space in the frame of the Conference on Disarmament. China and Russia who together put forward a draft Treaty on Prevention of the Placement of Weapons in Outer Space and of the Threat or Use of Force against Outer Space Objects (PPWT) in 2008 would not feel comfortable either because the EU initiatives will steal the lime light. Consequently their reactions are understandably passive towards the Draft Code while the reaction of the USA to the PPWT was a clear cut "No". With the above background, the future of the EU Code is uncertain. Nevertheless, the purpose of the Code to reduce the space debris, to allow exchange of the information on the space activities, and to protect the space objects through safety and security, all to maximize the principle of the peaceful use and exploration of the outer space is the laudable efforts on the part of EU. When the detailed negotiations will be held, some problems including the cost to be incurred by setting up an office for the clerical works could be discussed for both efficient and economic mechanism. For example, the new clerical works envisaged in the Draft Code could be discharged by the current UN OOSA (Office for Outer Space Affairs) with minimal additional resources. The EU's initiatives are another meaningful contribution following one due to it in adopting the Kyoto Protocol of 1997 to the UNFCCC (UN Framework Convention on the Climate Change) and deserve the praise from the thoughtful international community.

• The Journal of Korean Academy of Prosthodontics
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• v.46 no.4
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• pp.409-419
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• 2008

Statement of problem: At all times people have tried to fabricate tooth restorations using tooth colored materials. Recently, demands for esthetics, even in restorations requiring strength, has brought a revolution to dentistry and increased use of zirconia. The basic color of zirconia is white to ivory. The color can be partially adapted by veneering it with ceramic materials. However, it would be better if the substructure could already be adapted to the basic color shade of neighboring teeth. By adaptation to the basic shade, it can help to reduce the necessary layer thickness of the veneer ceramic to achieve the desired color. Purpose: The purpose of this study was to spectrophotometrically evaluate the influence of shading of zirconia core on the final shade of all-ceramic restorations using the CIE $L^{*}a^{*}b^{*}$ system. Material and methods: Core specimens (n = 20 per group) of Lava Frame Zirconia, KaVo Everest Zirconia, Digident CAD/CAM Zirconia were fabricated at 20 mm in diameter and 0.5 mm in thickness. Halves of each groups were shaded in A3 color. These core specimens were veneered with A3 porcelain of the recommended manufacturer at thickness of 0.5 mm. CIE $L^{*}a^{*}b^{*}$ coordinates were recorded for each specimen with a spectrophotometer (Model CM-2600d, Minolta, Japan) at 0.5 mm, 0.4 mm, 0.3 mm in thickness. Color differences were calculated using the equation ${\Delta}E^{*}=[({\Delta}L^{*})2+({\Delta}a^{*})2+({\Delta}b^{*})2]1/2$. Results: 1. In the case where porcelain layer has a thickness of 0.5 mm, Lava Frame Zirconia and KaVo Everest group did not show clinically perceived color difference, however Digident CAD/CAM Zirconia group showed clinically perceived color difference according to shade allowed on core. 2. When the thickness of porcelain layer decreased from 0.5 mm to 0.4 mm, Lava Frame Zirconia and KaVo Everest group did not show clinically perceived color difference, on the other hand Digident CAD/CAM Zirconia group showed clinically perceived color difference according to shade allowed on core. 3. When the thickness of porcelain layer decreased from 0.5 mm to 0.3 mm, clinically perceived color differences were observed from all three groups. Conclusions: Ziroconia system, which is possible to allow shade on core, are thought to be much more favorable to reproduce natural shade compared to systems that is impossible to give shade. Therefore, clinicians ought to choose adequate system for certain clinical situation by considering above specific character.

• Fashion & Textile Research Journal
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• v.6 no.1
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• pp.41-50
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• 2004

This research proposes the on-stage costumes for the play Hamlet of Shakespeare performed by Yunheedan Guhri Pae - the Street Theater Troupe. Stage costumes have an important role in displaying the characteristics of each characters to the audience and has big visual effects. However, in order to design the costumes in the object viewpoints of the audience, the survey on the images of the characters who had actually watched the performance was taken place and proposed the costume design according to the results of the survey. Hamlet a: This result was applied to propose a sweater in black color, black leather pants and vest. Hamlet b: This result was applied to propose hooded coat in purple in middle level of brightness and color spectrum and yellow coat. For free image, loose pants in blue and vest in the same color tone were proposed. Gertrude a: This result was applied to use purple (violet) with reddish tone to propose the formation of a dress applying tailored suit. Gertrude b: This result was applied to propose purple gown and the one-piece dress with black laces. Ophelia a: This result was applied to propose feminine white dress and cape in purple color tone. Ophelia b: This result was applied to propose dyed and weaved clothes. Through the surveys as above, the images of each character was driven in adjectives, and using the results driven from the brightness, coloration, and color, color images were proposed. Only one costume cannot make up for the stage costumes and because it exists as an element of stage production, it is true that costumes are limited in some areas. However, that limit can become the motive of the costume. There is a limit, which the designer cannot produce the costumes as he or she had designed but I believe it is the center of the on-stage customers to display the characteristics of the characters according to the given concept. The limit of this research is the fact that because the costumes were designed so they fit the conditions already given, thus it was difficult to regard the process of designing and producing the costume as a project done according to the interaction. And in the future, if it is possible, I wish for the joint research with the people responsible for stage art to take place as a practical stage art. It was possible to produce practical costume since they were produced for actual performance and the production of costumes considering the dance steps, line of flow, and acting, was able to reduce the trial and error on stage. Through this research, I felt that the understanding and smooth interaction on diverse other areas not limited to the costume design should be taken place and believe that this was a research that proposes new research method since there had been only a few previous research regarding the on-stage costumes for actual performances. Therefore, this research had depended on the surveys given to the audiences to endow objectivity, however, I wish this research can contribute to defining effective process and methods for the on-stage costumes with more active researches with diverse methods and in diverse areas. I am sorry that the costume production for all the characters and all the scenes in Hamlet couldn't be done due to many limitations. As the following research assignment, I am planning on designing the costumes for all the scenes.