• Conservation and Restoration of Cultural Heritage
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• v.1 no.1
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• pp.39-48
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• 2012

The first twenty-five years of scientific study within Korea on Korean traditional ceramics has been characterized as a bridging effort to understand the rich field of artistic ceramic masterpieces on one hand with analytic results gained from mounds of broken shards and kiln wastes on the other. First shard pieces were collected directly from the waste mounds, but most of the analyzed shards were provided by art historians and museum staffs directly involved in systematic excavations. The scientific study is viewed as one of many complimentary ways in learning about the multi-faceted ceramics culture, ultimately connecting human spirits and endeavors from the past to the present to the future. About 1350 pieces of analyzed shards have been so far collected and organized according to the production location and time period. From the experimental results of the analysis, the compositional and microstructural characteristics of bodies and glazes have been deduced for many kiln sites of Goryeo and Joseon dynasties. Except for a few local kilns, porcelain stone was used as body material in both dynasties. The principle of mixing a clay component with a flux material was used in Korean glazes as was in China. The clay component different from body clay was often used early on. In Gangjin a porcelain material appropriate for whiteware body was mixed for celadon glaze, and in Joseon Gwangju kilns glaze stone was chief clay material. The use of wood ash persisted in Korea even in making buncheong glazes, but in Joseon whitewares burnt lime and eventually crushed lime were used as flux material.

• The Korean Journal of Cytopathology
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• v.7 no.2
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• pp.169-176
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• 1996

This study was peformed in order to evaluate the usefulness of the crush cytologic features and differential diagnosis between meningiomas and schwannomas in the central nervous system. Deeply seated and unusually located meningiomas and schwannomas with equivocal or erroneous frozen section diagnosis can be correctly diagnosed cytologically in crush preparations. Twenty-four meningiomas and nine schwannomas were studied by frozen section and crush preparation technique. These tumors displayed distinctive cytologic features. in meningiomas, the tumor tissue fragments were easy to crush, and the tumor cells were arranged in small clusters, flat sheets, papilla-like, whorling pattern or singly. Individual tumor cells displayed round or oval nuclei with finely granular chromatin pattern and inconspicuous small nucleoli. Occasionally psammoma bodies, nuclear pseudoinclusion or nuclear grooves were found. In schwannomas, tissue fragments were hard in consistency and difficult to crush. The crushed tissue presented as thick, irregular fragments with shard borders. The cells showed ill-defined cytoplasm and round, oval, cigar-shaped or curved nuclei. It is important to emphasize that the smear pattern under low-power view and cytologic features are helpful in discriminating between these two tumors.

• The Journal of the Petrological Society of Korea
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• v.26 no.2
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• pp.153-163
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• 2017

The Naeyeonsan Tuff is a stratigraphic unit which is distinguished as a cooling unit in the volcanic rocks of the northern Pohang. The Naeyeonsan Tuff, which is composed of crystals of plagioclase, quartz and hornblende, glasses of pumice and shard, and lithics of dacite, rhyolite, sandstone and shale, belongs to a lapilli tuff field according to the granulometric classification and to a vitric tuff field according to the constituent classification. The tuffs mostly develop welding foliations by dense welding and flatterning pumices and shards, and show several flow indicators by pyroclastic flowing. We can know a movement pattern from flow lineations and imbrications by pumices and lithics, and lateral gradings in isopleth map by average largest lithics and pumices in the Naeyeonsan Tuff, which indicate that the Naeyeonsan Tuff had a possible source area from the southeastern part.

• Journal of the Korea Society of Computer and Information
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• v.26 no.12
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• pp.143-150
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• 2021

In the recent power industry, a change is taking place from manual meter reading to remote meter reading using AMI(Advanced Metering Infrastructure). If such the power data generated from the AMI is recorded on the blockchain, integrity is guaranteed by preventing forgery and tampering. As data sharing becomes transparent, new business can be created. However, Ethereum blockchain is not suitable for processing large amounts of transactions due to the limitation of processing speed. As a solution to overcome such the limitation, various On/Off-Chain methods are being investigated. In this paper, we propose a interface server using data sharding as a solution for storing large amounts of power data in Etherium blockchain environments. Experimental results show that our power-data processing system with sharding method lessen the data omission rate to 0% that occurs when the transactions are transmitted to Ethereum and enhance the processing speed approximately 9 times.

• Journal of Platform Technology
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• v.11 no.6
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• pp.89-105
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• 2023

With the development of information technology, most of the information has been converted into digital information, leading to the Big Data era. The demand for search platform has increased to enhance accessibility and usability of information in the databases. Big data search software platforms consist of two main components: (1) an indexing component to generate and store data indices for a fast and efficient data search and (2) a searching component to look up the given data fast. As an amount of data has explosively increased, data indexing performance has become a key performance bottleneck of big data search platforms. Though many companies adopted big data search platforms, relatively little research has been made to improve indexing performance. This research study employs Elasticsearch platform, one of the most famous enterprise big data search platforms, and builds physical clusters of 3 nodes to investigate optimal indexing performance configurations. Our comprehensive experiments and studies demonstrate that the proposed optimal Elasticsearch configuration achieves high indexing performance by an average of 3.13 times.

• Journal of KIISE:Computer Systems and Theory
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• v.30 no.1
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• pp.33-49
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• 2003

Recently, there have been large storage demands for manipulating multimedia data. To solve the tremendous storage demands, one of the major researches is the SAN(Storage Area Network) that provides the local file requests directly from shared-disk storage and also eliminates the server bottlenecks to performance and availability. SAN also improve the network latency and bandwidth through new channel interface like FC(Fibre Channel). But to manipulate the efficient storage network like SAN, traditional local file system and distributed file system are not adaptable and also are lack of researches in terms of a metadata structure for large-scale inode object such as file and directory. In this paper, we describe the architecture and design issues of our shared-disk file system and provide the efficient bitmap for providing the well-formed block allocation in each host, extent-based semi flat structure for storing large-scale file data, and two-phase directory structure of using Extendible Hashing. Also we describe a detailed algorithm for implementing the file system's device driver in Linux Kernel and compare our file system with the general file system like EXT2 and shard disk file system like GFS in terms of file creation, directory creation and I/O rate.

• The Journal of the Korea Contents Association
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• v.12 no.5
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• pp.541-552
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• 2012

The purpose of the study was to investigate the effects of On-Line Community Assisted Team Learning (OCATL) activities on academic achievement and team member's Shared Mental Model(SMM) subscale scores. Two studies were conducted over two semesters in different universities. The first study was aimed at examining the effects of OCATL on university students' academic achievement using pre- and post- experimental design. For this experiment, 133 university students composed of 80 male and 53 female students from 13 colleges participated. The OCATL activities included the orientation of OCATL, seminar on collaborative learning, on-line community assisted team learning with sixteen hour participation during one semester and a final report (or a term paper). To measure these students' academic achievement, their pre- and post-semester's GPA were compared. The results of paired t-test revealed a significant difference in academic achievement (p<.05). The second study was designed to compare the scores of SMM subscales of the experimental group with the OCATL activities and those of the control group without using OCATL activities. The data was collected using the scale of Shared Mental Model(SMM)-short version developed by Johnson in 2011[18]. For this study, 74 participants from 10 teams served as an experimental group and 15 teams which were not exposed to OCATL activities served as a control group. The MANOVA results showed that SMM subscores of two groups measured after the experiment were statistically significantly different: The experimental group with the OCATL activities showed high scores on general task and team knowledge, general task and communication skills, attitudes toward team and task, team dynamics and interactions, team resources and working environment, and satisfaction with the team.

• Proceedings of the Korean Information Science Society Conference
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• 1998.10c
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• pp.279-281
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• 1998

CSCW는 지리적으로 분산된 작업자 간의 효율적인 의사소통을 위해 화상회의, 채팅(chatting), 화이트 보드(white board), 그리고 텔리포인팅(telepointing)과 같은 기능들을 제공한다. 이 중 텔리포인팅은 지역 시스템(local system)의 공유 윈도우(shard window)에서 텔리포인터(telepointer)를 통해 발생한 이벤트를 원격지 시스템(remote System)의 공유 윈도우에서 나타낼 수 있도록 하는 기능을 제공함으로써 작업자 간의 보다 효율적인 의사소통을 가능하게 한다. 이러한 의사소통 기능으로써의 텔리포인팅은 원격진료, 공동작업 플랫폼에 관한 연구에서 응용된 바 있으나 공동저작을 위한 텔리포인팅 기능에 관한 연구 및 이를 공동저작 관리 시스템 구조에 관한 연구가 미흡하다. 공동제작에서의 텔리포인팅은 저작자 간의 의사소통을 위한 기능 뿐만 아니라 동기적 공동저작과 동기적 프리젠테이션을 위한 기능으로써 응용될 수 있어야 한다. 이를 위해 공동저작 관리 시스템은 저작자 그룹인 세션(session) 단위로 텔리포인터에 대한 권한 관리와 텔리포인팅을 통한 공유객체 엑세스(access) 기능을 제공해야 한다. 또한 텔리포인팅 구조(telepointing architecture)는 텔리포인팅 이벤트의 멀티캐스팅(multicasting) 및 동기화(synchronization)를 위해 중앙에서 이벤트를 조정하는 텔리포인팅 조정 에이전트 (telepointing coordination agent)와 각 저작자의 지역 시스템에 존재하며 공유 윈도우로부터 지역 이벤트(local event)를 인식하고 텔리포인팅 이벤트를 공유 윈도우에 알리는 텔리포인팅 지역 에이전트(telepointing local agent)로 구성되어야 한다. 본 논문은 공동저작을 위한 텔리포인팅의 기능들과 이를 위한 공동저작 관리 시스템 구조를 설명하고 텔리포인팅 구조를 제시한다.cid 함량이 가장 많이 용출된 분획은 sodium hydroxide 부분으로서 hemicellulose구조가 polyuronic acid의 형태인 것으로 사료된다. 추출획분의 구성단당은 여러 곡물연구의 보고와 유사하게 glucose, arabinose, xylose 함량이 대체로 높게 나타났다. 점미가 수가용성분에서 goucose대비 용출함량이 고르게 나타나는 경향을 보였고 흑미는 알칼리가용분에서 glucose가 상당량(0.68%) 포함되고 있음을 보여주었고 arabinose(0.68%), xylose(0.05%)도 다른 종류에 비해서 다량 함유한 것으로 나타났다. 흑미는 총식이섬유 함량이 높고 pectic substances, hemicellulose, uronic acid 함량이 높아서 콜레스테롤 저하 등의 효과가 기대되며 고섬유식품으로서 조리 특성 연구가 필요한 것으로 사료된다.리하였다. 얻어진 소견(所見)은 다음과 같았다. 1. 모년령(母年齡), 임신회수(姙娠回數), 임신기간(姙娠其間), 출산시체중등(出産時體重等)의 제요인(諸要因)은 주산기사망(周産基死亡)에 대(對)하여 통계적(統計的)으로 유의(有意)한 영향을 미치고 있어 $25{\sim}29$세(歲)의 연령군에서, 2번째 임신과 2번째의 출산에서 그리고 만삭의 임신 기간에, 출산시체중(出産時體重) $3.50{\sim}3.99kg$사이의 아이에서 그 주산기사망률(周産基死亡率)이 각각 가장 낮았다. 2. 사산(死産)과 초생아사망(初生兒死亡)을 구분(區分)하여 고려해 볼때 사산(死産)은 모성(母性)의 임신력(姙娠歷)과 매우 밀접한 관련이 있는 것으로 사료(思料)되었고 초생아사망(初生兒死亡)은 미숙아(未熟兒)와 이에 관련된 병발이 거의 결정적(決定的) 원인(原因)이 된다고 사료(思料)되었다. 3. 주산기사망률(周産基死亡率)을 감소시키는 관점(觀點)에서의 모자보건사업(母子保健事業)은 미숙아방지책(未熟兒防止策

• Journal of Conservation Science
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• v.30 no.1
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• pp.67-80
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• 2014

This study examined the chemical characteristics and the microstructure of Goryeo whiteware which was excavated in the kiln site Yucheon-ri, Gangwon-do, the southern part of South Korea. this area is considered to be used in the middle of the time of Goryeo Dynasty. We analyzed the chemical characteristics comparing Goryeo Whiteware from Seo-ri, Jungam-ri, Bangsan-dong and The temple site of Beopcheon. Based on the analysis, we confirmed the properties of raw material for making pottery. It is featured that body composition of Goryeo Whiteware from Yucheon-ri contains high silica and low solvent. However, the contents of the glaze are vice versa. Goryeo whiteware tends to contain larger part of oxide than that of titanium oxide, which applies to Goryeo Celadon. the whitewares during the early days of Goryeo Dynasty varies in components depending on kilns, whereas it does not mean that chronological changes happened in components. The whiteware shards from Yuchoen-ri have a similar aspect. The whiteware shard from the temple of Beopchen differ in composition, Thus they are estimated to have been produces and shipped from various sites. In conclusion, we judged that the component difference among Goryeo whitewares stems from production environment and origin of raw materials rather than chronological changers.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.17 no.2
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• pp.99-114
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• 2022

Crowdfunding is one of new financing alternatives and is innovative and creative. In order to proceed with crowdfunding, various functions are required, such as design for screen composition, marketing and promotion for the public, accounting to manage the collected funds, and product production and purchase for reward. In addition, since it is a project that must be completed in a short period of time, cooperation between team members is important. This paper studied how the characteristics of the team conducting crowdfunding affect the team performance in crowdfunding. In this study, we set functional background diversity and shared leadership necessary for crowdfunding as team characteristic variables and crowdfunding amount, completion of work and team innovation as team performance variables. This study tests the hypotheses from 220 university students in 79 teams. The findings suggest that functional diversity and shared leadership are positively related to the completion of work and team innovation but not related to crowdfunding amount. To date, few studies have studied the relationship between characteristics of the crowdfunding team and performance. Therefore, the study on functional diversity and shared leadership in crowdfunding can expand existing crowdfunding study area.