• Journal of Information Processing Systems
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• v.10 no.2
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• pp.271-282
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• 2014

The advancement of knowledge society has enabled the social network community (SNC) to be perceived as another space for learning where individuals produce, share, and apply content in self-directed ways. The content generated within social networks provides information of value for the participants in real time. Thus, this study proposes the social network community activity-based content model (SoACo Model), which takes SNC-based activities and embodies them within learning objects. The SoACo Model consists of content objects, aggregation levels, and information models. Content objects are composed of relationship-building elements, including real-time, changeable activities such as making friends, and participation-activity elements such as "Liking" specific content. Aggregation levels apply one of three granularity levels considering the reusability of elements: activity assets, real-time, changeable learning objects, and content. The SoACo Model is meaningful because it transforms SNC-based activities into learning objects for learning and teaching activities and applies to learning management systems since they organize activities -- such as tweets from Twitter -- depending on the teacher's intention.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.48 no.3
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• pp.208-216
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• 2012

The properties of sediment collected from seabed surface to 6cm depth on the four positions were analyzed to investigate turbulence of marine sediments by shrimp beam trawl. Types of sediments in the investigation area were (g)mS (slightly gravely muddy sand) and gmS (gravely muddy sand) showing high sand content, and (g)sM (slightly gravely sandy mud), gsM (gravely sandy mud) as well. It is estimated that position is more crucial factor than seasonal difference for the granularity variation of sediment in each investigation area. Finding the positional characteristics of sediment granularity was difficult before removing shells and organic matter. However, the average granularity is getting larger by going out from inland sea to open sea once those were removed. The granularity of marine sediment got narrow after processing in the fishing area for shrimp beam trawl but there was no big difference for granularity size before and after processing in the non-fishing area. This might be attributed to crushed shell particles going up and down again on the surface in the fishing area. To demonstrate the hypothesis mentioned above, the sediments driven by shrimp beam trawl need to be collected and analyzed.

• Proceedings of the Korea Information Processing Society Conference
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• 2002.11c
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• pp.1915-1918
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• 2002

Managing semistructured data needs fine granularity such as markup elements. XML has major effect in managing web content, it enables content reusability, enriches information with metadata, ensures valid document links, etc. We introduce our content model as an integrated work which handles content objects as controllable units. The paper concerns on modeling news site and how the content is classified due to the site structure, aggregated content and reusability. The model stores instance XML document into relation database using fragmentation strategy.

• The Transactions of the Korea Information Processing Society
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• v.7 no.2
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• pp.347-354
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• 2000

This paper presents the efficient mechanisms for concurrency control and writing authority control in collaborative writing system are represented by the tree structures which consist of the logical objects and the content objects connected to the terminal objects of trees. For concurrency control, we adopted the approach to extend the multiple-granularity-locking-scheme. This scheme allows us to lock any objects at each level of the hierarchy. We also defined the locking compatibility table by analysing the operations applicable to any objects at each level of the hierarchy. We finally suggest the extended-multiple-granularity-locking mechanism which uses the locking compatibilility table for deciding to lock an object. This scheme gives the benefit to maximize the possibility of concurrent accessing to the shared objects. In addition, we suggest a mechanism for writing authority control which prohibits the Non-Group users from modifying the shared objects based on the concept of Group/Non-Group The proposed mechanism allows us to protect copyright very reasonably.

• Journal of Korean Society of Water and Wastewater
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• v.24 no.5
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• pp.609-615
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• 2010

This study examined the change of water content in sludge using direct current electric equipment for decreasing the amount of sludge. The experiment showed that the average density of solids in the sludge treated by direct current before the centrifugal dewatering process was increased by 47.8%, when compared to those not treated by direct current. From the result of measuring the granularity of the sludge by the direct current treatment, that the average particle size of the sludge that was not exposed to the electric current was 52.36 ${\mu}m$, and more than 90% of the sludge was <94.29 ${\mu}m$ in size. On the other hand, the average particle size of the sludge passed through the direct current was 28.67 ${\mu}m$, and more than 90% of the sludge was 52.46 ${\mu}m$. This means that the average particle size of the sludge treated by the direct current was 45.2% smaller, and the standard deviation of granularity was improved. Because of water that separated from sludge moves to the (+) pole, larger particles become smaller and fine particles combine together, resulting in the equalization of the particle size. On the sludge after the centrifugal dehydrator, the change of the water content by the direct current was measured. The results showed that the average density of the solids was increased by 44.2% compared.

• Journal of Fisheries and Marine Sciences Education
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• v.29 no.1
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• pp.325-331
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• 2017

This study was conducted the change of physico-chemical characteristics according to salt types; sun-dried salt, refined salt, Chinese sun-dried salt, salicornia herbacea salt and bamboo salt. As a results, volatile basic nitrogen(VBN) contents were 143.24-148.32 mg/100g, amino nitrogen(AN) contents were 1050.37-1096.91 mg/100g, total nitrogen(TN) contents were 1.62-1.78 %, moisture contents were 64.19-66.00 % and pH were 5.23-5.98. There are various type of salts that have difference in content of salinity, moisture, various mineral content, size and shape of salt crystal, granularity and chromaticity. In this study, Than the difference in the salt, difference in the fish sauce is determined to be insignificant, that is, there are no significant effect on the quality of the fish sauce according to the kind of salt.

• Journal of the Korea Institute of Building Construction
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• v.8 no.4
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• pp.105-114
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• 2008

This study investigates the saturation level of surface dryness, quantity of adhesive mortar, and the alien substance content of recycled aggregates for concrete to develop an adequate quality testing method for understanding the properties of recycled aggregates, which differ greatly from preexisting aggregates. For tests that measure the saturation level of surface dryness, where detail methods are applied differently according to the tester, various testing methods from across world were compared and analyzed. This study revealed that when measuring the saturation level of surface dryness of a certain sample, aggregates must be supplemented immediately whenever the height of the sample becomes lower than the measuring mold, and allowing the tamper to free fall on the sample will provide the most accurate results. When measuring the quantity of adhesive mortar of recycled aggregates for concrete, an acid solution was used, and since the quantity of adhesive mortar increases as the particle sizes gets smaller, the sample for testing should represent the entire granularity. Sulfuric acid solution is adequate for immersion, and the concentration should be 20% for best results. According to the alien substance content measurement, which was examined by the naked eye, the error range caused by the difference in particle size was neglectable, and therefore the sample should be $2.5{\sim}5.0mm$ in size concerning the accuracy and measuring time. Also, for coarse recycled aggregates, the sample should amount to 1kg for measuring alien substance content by the naked eye, which proves that assortment by the naked eye is the most adequate method for measuring the alien substance content of a recycled aggregate.

• Journal of the Korean GEO-environmental Society
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• v.12 no.8
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• pp.13-24
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• 2011

In the part of geotechnical engineering, soils are classified as either the coarse grained soil or the fine-grained soil following the fine content($F_c$=50%) according to the granularity, and appropriate design codes are used respectively to represent their mechanical behaviour. However, sand-clay mixtures, which are typically referred to as intermediate soils, cannot be easily categorized as either sand or clay. In this study, several monotonic undrained shear tests were carried out on Silica sand fine mixtures with various proportions, and a wide range of soil structures, ranging from one with sand dominating the soil structure to one with fines controlling the behaviour, were prepared using compaction method or pre-consoldation methods in prescribed energy. The shear strength of mixtures below the threshold fines content is observed that as the fines content increases, maximum deviator stress ratio decrease for dense samples while an increase is noted for loose samples. Then, by using the concept of fines content and granular void ratio, the monotonic shear strength of the mixtures was estimated. It was found that the shear behavior of mixtures is greatly dependent on the skeleton structure of sand particles.

• Korean Journal of Remote Sensing
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• v.33 no.4
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• pp.411-422
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• 2017

This research aims to analyze spectral reflectance of intertidal zone and its changes under various environmental conditions. We sampled sand of Mongsanpo tidal flat, Korea, and measured its spectral reflectance by using a spectroradiometer under various water contents, compositions and granularity. We also simulated the reflectance of Landsat 7 ETM+ and compared it with an actual satellite data. Five locations were selected for sampling from the coastline towards the ocean. Grain size diminished stepwise from the coastline to ocean direction, while spectral reflectance differed with wavelength. Water contents lowered the overall reflectance especially at the water absorption bands. Spectral reflectance data were then converted into the simulated one by using Landsat 7 ETM+ spectral reflectance function to be compared with the actual Landsat 7 ETM+ images. It showed the decrease of the spectral reflectance due to the increase of moisture contents from seashore towards the ocean. It is shown that Landsat 7 ETM+ imagery can be efficient to extract moisture contents in the tidal flat while compositional analysis needs satellite sensors with much higher spectral resolution.

• The Transactions of the Korea Information Processing Society
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• v.6 no.5
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• pp.1153-1165
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• 1999

In various fields of information technology, it is growing up the needs about dynamic content management systems to store and manage SGML(Standard Generalized Markup language) documents in a database system. In this paper, we consider the issue of storing SGML documents that having complex hierarchical structure into a database system, and then propose a data model based on ODMG(Object Database Management Group) object model in order to store SGML documents without loss of information. Because the proposed data model reflects physical element structure and logical entity structure of SGML documents, it is able to store the SGML document in a database system at the system at the element- level granularity without any information loss. And also the proposed data model can be adapted among ODMG-compliant object database management systems. Finally, we will discuss on the implementation details of SGML repository system supports the functionality of automatic database schema creation for any DTD(Document Type Definition0, the functionality of storing the SGML document, the functionality of dynamic document assembly from stored database objects to SGML document, and the functionality of indexing and searching for database objects.