• Journal of the Korean Society of Combustion
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• v.13 no.2
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• pp.23-32
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• 2008

Gasification characteristics in the fluidized bed reactor are essential for the design of a gasification furnace to optimize the operation condition. Moisture content of the solid fuel is one of the important factors to influence directly the gasification characteristics. So it is necessary to investigate the effect of moisture content of solid fuel in partial oxidation condition. Gasification characteristics are investigated with results from thermogravimetric analyzer and lab-scale fluidized bed reactor for wood and RDF samples along with changing moisture contents. Additionally lab-scale fluidized bed reactor was run continuously and gas concentrations at the exit were measured. It is observed that the rate of reaction in partial oxidation condition is between the results from the combustion environment and from the inert condition. Moisture content in a particle slows down the heating rate of a particle. So, reaction is delayed by the moisture content. However, RDF samples those are easy to break-up don't show the effect of moisture content. The result of continuous operation condition shows that proper moisture content promotes gasification because steam from the particles helps gasification of the solid fuel. A simulation to predict the syn-gas composition was conducted by the Aspen Plus process simulator. The cold gas efficiency of the experiment was compared with results from the simulation.

• 한국연소학회:학술대회논문집
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• 2007.05a
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• pp.161-167
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• 2007

Gasification characteristics in the fluidized bed reactor are essential for the design of a gasification furnace to optimize the operation condition. Moisture content of the solid fuel is one of the important factors to influence directly the gasification characteristics. So it is necessary to investigate the effect of moisture content of solid fuel in gasification process. Gasification characteristics are investigated with results from thermogravimetric analyser and lab-scale fluidized bed reactor for wood and RDF samples along with changing moisture contents. Additionally lab-scale fluidized bed reactor was run continuously and gas concentrations at the exit were measured. It is observed that the rate of reaction in partial oxidation condition is in between the results from the combustion environment and from the inert condition. Moisture content in a particle slows down the heating rate of a particle. So, reaction time is delayed by the moisture content. However, RDF samples that are easy to break-up doesn't show the effect of moisture content. The results of continuous operation condition shows that proper moisture content promotes gasification because steam from the particles helps gasifcation of the sold fuel.

• Journal of the Korean Society for information Management
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• v.24 no.3
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• pp.271-297
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• 2007

Since the use of the Internet has proliferated, the availability of illegal and harmful content has been a great concern to both governments and Internet users. Among various solutions for issues related to such content, Internet content filtering technologies have been developed for enabling users to deal with harmful content. In recent years, commercial filtering has become massively popular. Many parents, teachers and even governments have chosen commercial filtering software as a feasible technical solution for protecting minors from harmful information on the Internet. The Internet content filtering software market has grown significantly. However, Internet content filtering software has led to intense debate among civil liberties groups, They deem this to be censorship and argue that Internet filtering technologies are simply unworkable because they have inherent weaknesses. They are critical of the fact that most filtering has violated free speech rights and will eventually wipe out honor and controversial, yet innocent incidences of free speech on the Internet. In this article Internet content filtering, in particular PICS/RDF-based label filtering, so-called Internet content rating system, will be explored and its advantages and drawbacks relating to end-users' autonomy and freedom of expression will be discussed.

• Resources Recycling
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• v.12 no.4
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• pp.58-64
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• 2003

A study on the preparation of RDF with ASR materials from shredder line of end-of-life vehicles has been peformed by using hot molding method. ASR materials used in the work were plastics, fibers and sponge which were cut by less than 10 mm in size prior to hot molding and 40, 60 and 80 mm mold in diameter were employed for RDF forming. It was found that heating temperature, heating time and mixing ratio of materials played an important role in the hot molding of ASR materials. Density of RDF samples Prepared in the work was in the range of 0.5∼0.9gr/ml depending on the hot molding conditions and it was decreased with increase in the content of sponge. Breaking strength of RDF samples was observed to 0.8∼3.0MPa and it was also increased with increase in density of RDF samples. Finally, when heating temperature was elevated, density of RDF was increased due to Increase in molten part of ASR materials which resulted in the enhancement of breaking strength of RDF.

• Proceedings of the Korea Society for Simulation Conference
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• 2005.11a
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• pp.180-184
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• 2005

These days, home network connects all home appliances using one of broadband convergence network, is constructed and propagated to more than 10 million house hold. Users can monitor and control statuses of home appliances using mobile terminal through homeserver. For active propagation of home network, high-quality multimedia service is very important. Specially, as digital recorder and digital camera is propagated, new paradigm that private DVDs can be shared in many household shows up. The homeserver is the main part of UbiHome, which can store much multimedia content and through which the user can search and share these contents. For searching and sharing, the metadata of contents is supposed to keep the consistency. These metadata include the description to different format such as Image, movie, and music. Therefore, we intend to provide a RDF model for effectively storing, searching and managing high-quality contents in UbiHome. In this paper, we propose to make Ontology to close semantic approach using RDF/RDF Schema for managing multimedia data in UbiHome. we propose RDF-Based Local Ontology and merging these ontology to RDF-Based Global Ontology.

• Journal of the Korea Organic Resources Recycling Association
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• v.21 no.1
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• pp.76-84
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• 2013

In this study, thermal weight loss, non-isothermally experiment, chemical composition analysis, calorific value, activation energy (E) were investigated to analysis the kinetic study of RDF, wood pellets, waste wood, waste textile and waste vinyl. When the chemical composition of solidification fuel was compared, the moisture content of RDF was less than the wood pellet and when the kinetic study was compared, the combustion reaction rate of the waste vinyl was higher than any other solidification fuels. However when the combustion efficiency was compared by the activation energy, the RDF had the higher efficiency than other wastes. RDF can be found that the reaction takes place between $320{\sim}720^{\circ}C$ depending on the heating rate.

• Proceedings of the IEEK Conference
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• 2001.10a
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• pp.765-769
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• 2001

The refuse-derived fuel(RDF) is manufactured using waste plastics-based materials and its physical and chemical properties are analyzed. The manufacturing process consists of hand picking, primary magnetic separation, crushing, secondary magnetic separation, feeding and extrusion. The RDF products have a higher calorie content of over 6, 000 ㎉/kg and high stability because the waste plastics and paper are mainly selected. The combustion flue gas of RDF products is satisfied with the emission criteria of incinerator. The heavy metal concentration of combustion byproduct from the RDF boiler is also satisfied with the criteria and appears to be lower concentration than that of a common municipal waste incinerator.

• International Journal of Knowledge Content Development & Technology
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• v.4 no.1
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• pp.39-51
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• 2014

The paper proposes that the Basic Concepts Classification (BCC) could serve as the controlled vocabulary for the Semantic Web. The BCC uses a synthetic approach among classes of things, relators, and properties. These are precisely the sort of concepts required by RDF triples. The BCC also addresses some of the syntactic needs of the Semantic Web. Others could be added to the BCC in a bottom-up process that carefully evaluates the costs, benefits, and best format for each rule considered.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 2007.11a
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• pp.163-168
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• 2007

• Journal of the Korea Institute of Information and Communication Engineering
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• v.7 no.4
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• pp.612-622
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• 2003

This paper studied and proposed a XML document storing-and-retrieval framework based on a variant k-ary complete tree and a RDF metadata, which is composed of an effective storing module to store xml documents, a retrieving module to retrieve xml documents, and a connecting module to make this system intemperate in the web environment. In this storing module, DTD independent DOM based decomposition model using a method of addressing unique ill using a variant k-ary complete tree is adopted and is implemented. Query Processing Module includes a XPath query process and a content based retrieval function using word index for content information. To retrieve more exactly data, a structural retrieval using RDF metadata is adopted and implemented. In order to implement effectively XML document storing and retrieval system in the web environment, API using XML-RPC, API using HTTP's GET, PUT, POST and API using SOAP have been adopted and implemented.