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Development of an Offline Based Internal Organ Motion Verification System during Treatment Using Sequential Cine EPID Images (연속촬영 전자조사 문 영상을 이용한 오프라인 기반 치료 중 내부 장기 움직임 확인 시스템의 개발)

  • Ju, Sang-Gyu;Hong, Chae-Seon;Huh, Woong;Kim, Min-Kyu;Han, Young-Yih;Shin, Eun-Hyuk;Shin, Jung-Suk;Kim, Jing-Sung;Park, Hee-Chul;Ahn, Sung-Hwan;Lim, Do-Hoon;Choi, Doo-Ho
    • Progress in Medical Physics
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    • v.23 no.2
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    • pp.91-98
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    • 2012
  • Verification of internal organ motion during treatment and its feedback is essential to accurate dose delivery to the moving target. We developed an offline based internal organ motion verification system (IMVS) using cine EPID images and evaluated its accuracy and availability through phantom study. For verification of organ motion using live cine EPID images, a pattern matching algorithm using an internal surrogate, which is very distinguishable and represents organ motion in the treatment field, like diaphragm, was employed in the self-developed analysis software. For the system performance test, we developed a linear motion phantom, which consists of a human body shaped phantom with a fake tumor in the lung, linear motion cart, and control software. The phantom was operated with a motion of 2 cm at 4 sec per cycle and cine EPID images were obtained at a rate of 3.3 and 6.6 frames per sec (2 MU/frame) with $1,024{\times}768$ pixel counts in a linear accelerator (10 MVX). Organ motion of the target was tracked using self-developed analysis software. Results were compared with planned data of the motion phantom and data from the video image based tracking system (RPM, Varian, USA) using an external surrogate in order to evaluate its accuracy. For quantitative analysis, we analyzed correlation between two data sets in terms of average cycle (peak to peak), amplitude, and pattern (RMS, root mean square) of motion. Averages for the cycle of motion from IMVS and RPM system were $3.98{\pm}0.11$ (IMVS 3.3 fps), $4.005{\pm}0.001$ (IMVS 6.6 fps), and $3.95{\pm}0.02$ (RPM), respectively, and showed good agreement on real value (4 sec/cycle). Average of the amplitude of motion tracked by our system showed $1.85{\pm}0.02$ cm (3.3 fps) and $1.94{\pm}0.02$ cm (6.6 fps) as showed a slightly different value, 0.15 (7.5% error) and 0.06 (3% error) cm, respectively, compared with the actual value (2 cm), due to time resolution for image acquisition. In analysis of pattern of motion, the value of the RMS from the cine EPID image in 3.3 fps (0.1044) grew slightly compared with data from 6.6 fps (0.0480). The organ motion verification system using sequential cine EPID images with an internal surrogate showed good representation of its motion within 3% error in a preliminary phantom study. The system can be implemented for clinical purposes, which include organ motion verification during treatment, compared with 4D treatment planning data, and its feedback for accurate dose delivery to the moving target.

Studies on the Directivity of Gokjungkyeong(Kyung Overlapped with Gok) which was specified in Byeokgye-ri, Yangpyeong-gun and the Hwaseo Lee, Hang-ro's Management in Byeokwon Garden (양평 벽계리에 설정된 곡중경(曲中景)의 지향성과 화서(華西) 이항로(李恒老)의 벽원(蘗園) 경영)

  • Jung, Woo-Jin;Rho, Jae-Hyun
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.34 no.3
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    • pp.78-97
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    • 2016
  • The objectives of this study are to examine the context of the establishment of Suhoe Gugok, Byeokgye Gugok Vally, and Nosan Palkyung, which have been established in Seojong-myeon of Yangpyeong-gun, by literature review and site investigations, and to determine the sceneries of Byeokgye scenic site as enjoyed and managed during the period of Hwaseo Lee, Hang-ro(華西 李恒老). The results of the study are as follows. First, Byeokgye Gugok Vally(黃蘗九曲) and Nosan Palkyung(蘆山八景), which have been established after the period of Hwaseo and theorized to have been established around key scenic areas associated with Hwaseo's activities, the analysis results showed that they were collecting sceneries of modern times. The extensive overlap between Byeokgye Gugok Vally and concentrated scenic elements of Suhoe Gugok(水回九曲), and the artificial configuration from the end point of Suhoe Gugok to the beginning point of Nosan Palkyung, reveal the pattern of space conflict and hegemony between Byeokgyes of Suip-ri and Nomun-ri. This is likely to be caused by the conflict between the historicity of the group that enjoyed Byeokgye prior to Hwaso's period and the strong territoriality of the space filled with the image of Hwaseo. Second, Byeokgye Gugok Vally was the secondary spatial system created by selecting the most scenic sites in Suip-ri while expanding the area of Nosan Palkyung. After establishment of Byeokgye Gugok Vally, the spatial identity of the entire Byeokgyecheon area was effectively established. This was a "Hwaseo-oriented" move, including the complete exclusion of the scenic sites from the pre-Hwaseo period such as Cheongseo Gujang and Suhoe Gugok's Letters Carved on the Rock. Consequently, the entire Byeokgyecheon area was reorganized into a cultural scenic site with Heoseo's influence. Third, Fifth, creations of Gugok(九曲) to determine the lineage of the Hwaseo School from Juja(朱子) to Yulgok(栗谷) to Uam(尤庵) to Hwaseo is likely to be an opportunity of birth and external motivation of the establishment of new Gugok Palkyung. In other words, Nosan Palkyung and Byeokgye Gugok Vally are likely to have been created as a reaction to the change of the center of the Hwaseo School to Okgyedong, and with strategic orientation based on the motivation and needs such as creation of the connecting space between Mui Gugok, Gosan Gugok, and Okgye Gugok, and the elevation of Hwaseo's status. Fourth, from the Hwaseo's Li-centric point of view, all revered sites in Beokwon(蘗園) that he managed existed as the spatial creative work to experience the existence of "li" through the objects in the landscape and the boundary of the spirit of emptiness of the aesthetic self. This clearly shows how Byeokgye Gugok Vally or Nosan Palkyung must be defined, and furthermore, appreciated and approached, prior to discussing it as the space associated with Hwaseo. Fifth, Nosan Palkyung was composed of cultural scenic landscapes of Gokjungkyung(曲中景) with eight scenic sites where Hwaseo gave his teachings and spend time around, in the Byeokgye of Nomun-ri area of Byeokgye Gugok Vally. The sceneries is, however, collected by depending on Hwaseo's Letters Carved on the Rock and poetry. Consequently, an inner exuberance of Nosan Palkyung is satisfied beside Byeokgye Gugok Vally, but its conceptual adequacy leaves room for questions.

Light and Electron Microscopy of Gill and Kidney on Adaptation of Tilapia(Oreochromis niloticus) in the Various Salinities (틸라피아의 해수순치시(海水馴致時) 아가미와 신장(腎臟)의 광학(光學) 및 전자현미경적(電子顯微鏡的) 관찰(觀察))

  • Yoon, Jong-Man;Cho, Kang-Yong;Park, Hong-Yang
    • Applied Microscopy
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    • v.23 no.2
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    • pp.27-40
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    • 1993
  • This study was taken to examine the light microscopic and ultrastructural changes of gill and kidney of female tilapia{Oreochromis niloticus) adapted in 0%o, 10%o, 20%o, and 30%o salt concentrations, respectively, by light, scanning and transmission electron microscope. The results obtained in these experiments were summarized as follows: Gill chloride cell hyperplasia, gill lamellar epithelial separation, kidney glomerular shrinkage, blood congestion in kidneys and deposition of hyalin droplets in kidney glomeruli, tubules were the histological alterations in Oreochromis niloticus. Incidence and severity of gill chloride cell hyperplasia rapidly increased together with increase of salinity, and the number of chloride cells in gill lamellae rapidly increased in response to high external NaCl concentrations. The ultrastructure by scanning electron microscope(SEM) indicated that the gill secondary lamella of tilapia(Oreochromis niloticus) exposed to seawater, were characterized by rough convoluted surfaces during the adaptation. Transmission electron microscopy(TEM) indicated that mitochondria in chloride cells exposed to seawater, were both large and elongate and contained well-developed cristae. TEM also showed the increased chloride cells exposed to seawater. The presence of two mitochondria-rich cell types is discussed with regard to their possible role in the hypoosmoregulatory changes which occur during seawater-adaptation. Most Oreochromis niloticus adapted in seawater had an occasional glomerulus completely filling Bowman's capsule in kidney, and glomerular shrinkage was occurred higher in kidney tissues of individuals living in 10%o, 20%o, 30%o of seawater than in those living in 0%o of freshwater, and blood congestion was occurred severer in kidney tissues of individuals living 20%o, 30%o of seawater than in those living in 10%o of seawater. There were decreases in the glomerular area and the nuclear area in the main segments of the nephron, and that the nuclear areas of the nephron cells in seawater-adapted tilapia were of smaller size than those from freshwater-adapted fish. Our findings demonstrated that Oreochromis niloticus tolerated moderately saline environment and the increased body weight living in 30%o was relatively higher than that living in 10%o in spite of histopathological changes.

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Comparison of CT based-CTV plan and CT based-ICRU38 plan in brachytherapy planning of uterine cervix cancer (자궁경부암 강내조사 시 CT를 이용한 CTV에 근거한 치료계획과 ICRU 38에 근거할 치료계획의 비교)

  • Shim JinSup;Jo JungKun;Si ChangKeun;Lee KiHo;Lee DuHyun;Choi KyeSuk
    • The Journal of Korean Society for Radiation Therapy
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    • v.16 no.2
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    • pp.9-17
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    • 2004
  • Purpose : Although Improve of CT, MRI Radio-diagnosis and Radiation Therapy Planing, but we still use ICRU38 Planning system(2D film-based) broadly. 3-Dimensional ICR plan(CT image based) is not only offer tumor and normal tissue dose but also support DVH information. On this study, we plan irradiation-goal dose on CTV(CTV plan) and irradiation-goal dose on ICRU 38 point(ICRU38 plan) by use CT image. And compare with tumor-dose, rectal-dose, bladder-dose on both planning, and analysis DVH Method and Material : Sample 11 patients who treated by Ir-192 HDR. After 40Gy external radiation therapy, ICR plan established. All the patients carry out CT-image scanned by CT-simulator. And we use PLATO(Nucletron) v.14.2 planing system. We draw CTV, rectum, bladder on the CT image. And establish plan irradiation-$100\%$ dose on CTV(CTV plan) and irradiation-$100\%$ dose on A-point(ICRU38 plan) Result : CTV volume($average{\pm}SD$) is $21.8{\pm}26.6cm^3$, rectum volume($average{\pm}SD$) is $60.9{\pm}25.0cm^3$, bladder volume($average{\pm}SD$) is $116.1{\pm}40.1cm^3$ sampled 11 patients. The volume including $100\%$ dose is $126.7{\pm}18.9cm^3$ on ICRU plan and $98.2{\pm}74.5cm^3$ on CTV plan. On ICRU planning, the other one's $22.0cm^3$ CTV volume who residual tumor size excess 4cm is not including $100\%$ isodose. 8 patient's $12.9{\pm}5.9cm^3$ tumor volume who residual tumor size belows 4cm irradiated $100\%$ dose. Bladder dose(recommended by ICRU 38) is $90.1{\pm}21.3\%$ on ICRU plan, $68.7{\pm}26.6\%$ on CTV plan, and rectal dose is $86.4{\pm}18.3\%,\;76.9{\pm}15.6\%$. Bladder and Rectum maximum dose is $137.2{\pm}50.1\%,\;101.1{\pm}41.8\%$ on ICRU plan, $107.6{\pm}47.9\%,\;86.9{\pm}30.8\%$ on CTV plan. Therefore CTV plan more less normal issue-irradiated dose than ICRU plan. But one patient case who residual tumor size excess 4cm, Normal tissue dose more higher than critical dose remarkably on CTV plan. $80\%$over-Irradiated rectal dose(V80rec) is $1.8{\pm}2.4cm^3$ on ICRU plan, $0.7{\pm}1.0cm^3$ on CTV plan. $80\%$over-Irradiated bladder dose(V80bla) is $12.2{\pm}8.9cm^3$ on ICRU plan, $3.5{\pm}4.1cm^3$ on CTV plan. Likewise, CTV plan more less irradiated normal tissue than ICRU38 plan. Conclusion : Although, prove effect and stability about previous ICRU plan, if we use CTV plan by CT image, we will reduce normal tissue dose and irradiated goal-dose at residual tumor on small residual tumor case. But bigger residual tumor case, we need more research about effective 3D-planning.

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A study on the Success Factors and Strategy of Information Technology Investment Based on Intelligent Economic Simulation Modeling (지능형 시뮬레이션 모형을 기반으로 한 정보기술 투자 성과 요인 및 전략 도출에 관한 연구)

  • Park, Do-Hyung
    • Journal of Intelligence and Information Systems
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    • v.19 no.1
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    • pp.35-55
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    • 2013
  • Information technology is a critical resource necessary for any company hoping to support and realize its strategic goals, which contribute to growth promotion and sustainable development. The selection of information technology and its strategic use are imperative for the enhanced performance of every aspect of company management, leading a wide range of companies to have invested continuously in information technology. Despite researchers, managers, and policy makers' keen interest in how information technology contributes to organizational performance, there is uncertainty and debate about the result of information technology investment. In other words, researchers and managers cannot easily identify the independent factors that can impact the investment performance of information technology. This is mainly owing to the fact that many factors, ranging from the internal components of a company, strategies, and external customers, are interconnected with the investment performance of information technology. Using an agent-based simulation technique, this research extracts factors expected to affect investment performance on information technology, simplifies the analyses of their relationship with economic modeling, and examines the performance dependent on changes in the factors. In terms of economic modeling, I expand the model that highlights the way in which product quality moderates the relationship between information technology investments and economic performance (Thatcher and Pingry, 2004) by considering the cost of information technology investment and the demand creation resulting from product quality enhancement. For quality enhancement and its consequences for demand creation, I apply the concept of information quality and decision-maker quality (Raghunathan, 1999). This concept implies that the investment on information technology improves the quality of information, which, in turn, improves decision quality and performance, thus enhancing the level of product or service quality. Additionally, I consider the effect of word of mouth among consumers, which creates new demand for a product or service through the information diffusion effect. This demand creation is analyzed with an agent-based simulation model that is widely used for network analyses. Results show that the investment on information technology enhances the quality of a company's product or service, which indirectly affects the economic performance of that company, particularly with regard to factors such as consumer surplus, company profit, and company productivity. Specifically, when a company makes its initial investment in information technology, the resultant increase in the quality of a company's product or service immediately has a positive effect on consumer surplus, but the investment cost has a negative effect on company productivity and profit. As time goes by, the enhancement of the quality of that company's product or service creates new consumer demand through the information diffusion effect. Finally, the new demand positively affects the company's profit and productivity. In terms of the investment strategy for information technology, this study's results also reveal that the selection of information technology needs to be based on analysis of service and the network effect of customers, and demonstrate that information technology implementation should fit into the company's business strategy. Specifically, if a company seeks the short-term enhancement of company performance, it needs to have a one-shot strategy (making a large investment at one time). On the other hand, if a company seeks a long-term sustainable profit structure, it needs to have a split strategy (making several small investments at different times). The findings from this study make several contributions to the literature. In terms of methodology, the study integrates both economic modeling and simulation technique in order to overcome the limitations of each methodology. It also indicates the mediating effect of product quality on the relationship between information technology and the performance of a company. Finally, it analyzes the effect of information technology investment strategies and information diffusion among consumers on the investment performance of information technology.

Principal Characteristics of Pinus parviflora S. et Z. Native to the Dagelet Island (울릉도(鬱陵島) 섬잣나무의 특성(特性)에 관(關)한 연구(硏究))

  • Ahn, Kun Yong
    • Journal of Korean Society of Forest Science
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    • v.12 no.1
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    • pp.31-43
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    • 1971
  • In order to examine the taxonomic difference between the type of Pinus parviflora S. et Z. native to the Dagelet Island and the type of the species introduced to a number of places of the inland of South Korea, investigations on principal characters of needle, cone and seed were made with a hope to obtain informations on the evaluation of the species for possible use in the reforestation program in Korea in the future. Pinus parviflora is belonged to the Sub-genus Haploxylon of Genus Pinus and it has been speculated among dendrologists that this speoies is not monotypic. 308 rendomly selected trees from 8 different elevations of a natural stand of P. parviflora in the Dagelet Island, and 168 trees of P. parviflora growing at 15 different locations of the inland of South Korea were employed as samples along with 300 trees of P. koraiensis as control. The results obtained are summarized as follows: 1. The needle length of the Pinus parviflora of the Dagelet Island is longer than that of the species growing in the inland by 21-35 percent with statistical significancy. (Table 2) 2. In the cross section of needle, no resin canal was observed in about 50-70 percent of the sample trees of the Dagelet Island, whereas the resin canals appearing at external in most cases were observed in all sample trees from the inland. Consequently, the number of resin canals per needle was 0.4-0.9 with the Dagelet Island type and 2.0-2.7 with the inland type and these differences were statistically significant. (Table 3, Fig.2) 3. The Pinus parvviflora type of the Dagelet Island bas yellowish brown cones, and the Pinus parviflora type of Suwon and Kwangyang has redish brown cones. In both the length of cone and the number of cone scale, the difference between the type of the Dagelet Island and the type of the inland was also statistically significant. The cone scales of the Dagelet Island type are slightly opened, whereas the cone scales are widely opened with both of Suwon and Kwangyang type. (Table 4, Fig. 3) 4. the seed color, of the Dagelet Island type is yellowish brown, while it is greyish brown with Kwangyang and Suwon type. In the length and width of seed, the Dagelet Island type showed significantly larger values than that of the inland type. The length of seed was longest with the Kwangyang type being followed by Suwon and the Dagelet Island type in ordar. The seed wing of the Kwangyang type are longer than the seed, while that of the Dagelet Island type is degenerated to be shorter than the seed. (Table 5, Fig. 4) 5. The Pinus parviflora type of the Dagelat Island is similar in many respects to the southern type of Pinus parviflora of Japan except that many has no resin canals in the needle. 6. On the basis of the results obtained in this study, it may be concluded that the type of Pinus parviflora of the Dagelet Island is significantly different from the type of the species introduced to the inland and that there is no recognizable variation between the population of the different altitude of the Dagelet Island and the individual variation within population is also negligible. In the light of the high value of the tree not only as an ornamental tree but as an economical tree, The type of Pinus parviflora of the Dagelet Island is considered to be recommendable to be used for the future reforestation program of Korea.

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A Study on the Architecture of the Original Nine-Story Wooden Pagoda at Hwangnyongsa Temple (황룡사 창건 구층목탑 단상)

  • Lee, Ju-heun
    • Korean Journal of Heritage: History & Science
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    • v.52 no.2
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    • pp.196-219
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    • 2019
  • According to the Samguk Yusa, the nine-story wooden pagoda at Hwangnyongsa Temple was built by a Baekje artisan named Abiji in 645. Until the temple was burnt down completely during the Mongol invasion of Korea in 1238, it was the greatest symbol of the spiritual culture of the Korean people at that time and played an important role in the development of Buddhist thought in the country for about 700 years. At present, the only remaining features of Hwangnyongsa Temple, which is now in ruins, are the pagoda's stylobate and several foundation stones. In the past, many researchers made diverse inferences concerning the restoration of the original structure and the overall architecture of the wooden pagoda at Hwangnyongsa Temple, based on written records and excavation data. However, this information, together with the remaining external structure of the pagoda site and the assumption that it was a simple wooden structure, actually suggest that it was a rectangular-shaped nine-story pagoda. It is assumed that such ideas were suggested at a time when there was a lack of relevant data and limited knowledge on the subject, as well as insufficient information about the technical lineage of the wooden pagoda at Hwangnyongsa Temple; therefore, these ideas should be revised in respect of the discovery of new data and an improved level of awareness about the structural features of large ancient Buddhist pagodas. This study focused on the necessity of raising awareness of the lineage and structure of the wooden pagoda at Hwangnyongsa Temple and gaining a broader understanding of the structural system of ancient Buddhist pagodas in East Asia. The study is based on a reanalysis of data about the site of the wooden pagoda obtained through research on the restoration of Hwangnyongsa Temple, which has been ongoing since 2005. It is estimated that the wooden pagoda underwent at least two large-scale repairs between the Unified Silla and Goryeo periods, during which the size of the stylobate and the floor plan were changed and, accordingly, the upper structure was modified to a significant degree. Judging by the features discovered during excavation and investigation, traces relating to the nine-story wooden pagoda built during the Three Kingdoms Period include the earth on which the stylobate was built and the central pillar's supporting stone, which had been reinstalled using the rammed earth technique, as well as other foundation stones and stylobate stone materials that most probably date back to the ninth century or earlier. It seems that the foundation stones and stylobate stone materials were new when the reliquaries were enshrined again in the pagoda after the Unified Silla period, so the first story and upper structure would have been of a markedly different size to those of the original wooden pagoda. In addition, during the Goryeo period, these foundation stones were rearranged, and the cover stone was newly installed; therefore, the pagoda would seem to have undergone significant changes in size and structure compared to previous periods. Consequently, the actual structure of the original wooden pagoda at Hwangnyongsa Temple should be understood in terms of the changes in large Buddhist pagodas built in East Asia at that time, and the technical lineage should start with the large Buddhist pagodas of the Baekje dynasty, which were influenced by the Northern dynasty of China. Furthermore, based on the archeological data obtained from the analysis of the images of the nine-story rock-carved pagoda depicted on the Rock-carved Buddhas in Tapgok Valley at Namsan Mountain in Gyeongju, and the gilt-bronze rail fragments excavated from the lecture hall at the site of Hwangnyongsa Temple, the wooden pagoda would appear to have originally been an octagonal nine-story pagoda with a dual structure, rather than a simple rectangular wooden structure.

Development of Information Extraction System from Multi Source Unstructured Documents for Knowledge Base Expansion (지식베이스 확장을 위한 멀티소스 비정형 문서에서의 정보 추출 시스템의 개발)

  • Choi, Hyunseung;Kim, Mintae;Kim, Wooju;Shin, Dongwook;Lee, Yong Hun
    • Journal of Intelligence and Information Systems
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    • v.24 no.4
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    • pp.111-136
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    • 2018
  • In this paper, we propose a methodology to extract answer information about queries from various types of unstructured documents collected from multi-sources existing on web in order to expand knowledge base. The proposed methodology is divided into the following steps. 1) Collect relevant documents from Wikipedia, Naver encyclopedia, and Naver news sources for "subject-predicate" separated queries and classify the proper documents. 2) Determine whether the sentence is suitable for extracting information and derive the confidence. 3) Based on the predicate feature, extract the information in the proper sentence and derive the overall confidence of the information extraction result. In order to evaluate the performance of the information extraction system, we selected 400 queries from the artificial intelligence speaker of SK-Telecom. Compared with the baseline model, it is confirmed that it shows higher performance index than the existing model. The contribution of this study is that we develop a sequence tagging model based on bi-directional LSTM-CRF using the predicate feature of the query, with this we developed a robust model that can maintain high recall performance even in various types of unstructured documents collected from multiple sources. The problem of information extraction for knowledge base extension should take into account heterogeneous characteristics of source-specific document types. The proposed methodology proved to extract information effectively from various types of unstructured documents compared to the baseline model. There is a limitation in previous research that the performance is poor when extracting information about the document type that is different from the training data. In addition, this study can prevent unnecessary information extraction attempts from the documents that do not include the answer information through the process for predicting the suitability of information extraction of documents and sentences before the information extraction step. It is meaningful that we provided a method that precision performance can be maintained even in actual web environment. The information extraction problem for the knowledge base expansion has the characteristic that it can not guarantee whether the document includes the correct answer because it is aimed at the unstructured document existing in the real web. When the question answering is performed on a real web, previous machine reading comprehension studies has a limitation that it shows a low level of precision because it frequently attempts to extract an answer even in a document in which there is no correct answer. The policy that predicts the suitability of document and sentence information extraction is meaningful in that it contributes to maintaining the performance of information extraction even in real web environment. The limitations of this study and future research directions are as follows. First, it is a problem related to data preprocessing. In this study, the unit of knowledge extraction is classified through the morphological analysis based on the open source Konlpy python package, and the information extraction result can be improperly performed because morphological analysis is not performed properly. To enhance the performance of information extraction results, it is necessary to develop an advanced morpheme analyzer. Second, it is a problem of entity ambiguity. The information extraction system of this study can not distinguish the same name that has different intention. If several people with the same name appear in the news, the system may not extract information about the intended query. In future research, it is necessary to take measures to identify the person with the same name. Third, it is a problem of evaluation query data. In this study, we selected 400 of user queries collected from SK Telecom 's interactive artificial intelligent speaker to evaluate the performance of the information extraction system. n this study, we developed evaluation data set using 800 documents (400 questions * 7 articles per question (1 Wikipedia, 3 Naver encyclopedia, 3 Naver news) by judging whether a correct answer is included or not. To ensure the external validity of the study, it is desirable to use more queries to determine the performance of the system. This is a costly activity that must be done manually. Future research needs to evaluate the system for more queries. It is also necessary to develop a Korean benchmark data set of information extraction system for queries from multi-source web documents to build an environment that can evaluate the results more objectively.

KNU Korean Sentiment Lexicon: Bi-LSTM-based Method for Building a Korean Sentiment Lexicon (Bi-LSTM 기반의 한국어 감성사전 구축 방안)

  • Park, Sang-Min;Na, Chul-Won;Choi, Min-Seong;Lee, Da-Hee;On, Byung-Won
    • Journal of Intelligence and Information Systems
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    • v.24 no.4
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    • pp.219-240
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    • 2018
  • Sentiment analysis, which is one of the text mining techniques, is a method for extracting subjective content embedded in text documents. Recently, the sentiment analysis methods have been widely used in many fields. As good examples, data-driven surveys are based on analyzing the subjectivity of text data posted by users and market researches are conducted by analyzing users' review posts to quantify users' reputation on a target product. The basic method of sentiment analysis is to use sentiment dictionary (or lexicon), a list of sentiment vocabularies with positive, neutral, or negative semantics. In general, the meaning of many sentiment words is likely to be different across domains. For example, a sentiment word, 'sad' indicates negative meaning in many fields but a movie. In order to perform accurate sentiment analysis, we need to build the sentiment dictionary for a given domain. However, such a method of building the sentiment lexicon is time-consuming and various sentiment vocabularies are not included without the use of general-purpose sentiment lexicon. In order to address this problem, several studies have been carried out to construct the sentiment lexicon suitable for a specific domain based on 'OPEN HANGUL' and 'SentiWordNet', which are general-purpose sentiment lexicons. However, OPEN HANGUL is no longer being serviced and SentiWordNet does not work well because of language difference in the process of converting Korean word into English word. There are restrictions on the use of such general-purpose sentiment lexicons as seed data for building the sentiment lexicon for a specific domain. In this article, we construct 'KNU Korean Sentiment Lexicon (KNU-KSL)', a new general-purpose Korean sentiment dictionary that is more advanced than existing general-purpose lexicons. The proposed dictionary, which is a list of domain-independent sentiment words such as 'thank you', 'worthy', and 'impressed', is built to quickly construct the sentiment dictionary for a target domain. Especially, it constructs sentiment vocabularies by analyzing the glosses contained in Standard Korean Language Dictionary (SKLD) by the following procedures: First, we propose a sentiment classification model based on Bidirectional Long Short-Term Memory (Bi-LSTM). Second, the proposed deep learning model automatically classifies each of glosses to either positive or negative meaning. Third, positive words and phrases are extracted from the glosses classified as positive meaning, while negative words and phrases are extracted from the glosses classified as negative meaning. Our experimental results show that the average accuracy of the proposed sentiment classification model is up to 89.45%. In addition, the sentiment dictionary is more extended using various external sources including SentiWordNet, SenticNet, Emotional Verbs, and Sentiment Lexicon 0603. Furthermore, we add sentiment information about frequently used coined words and emoticons that are used mainly on the Web. The KNU-KSL contains a total of 14,843 sentiment vocabularies, each of which is one of 1-grams, 2-grams, phrases, and sentence patterns. Unlike existing sentiment dictionaries, it is composed of words that are not affected by particular domains. The recent trend on sentiment analysis is to use deep learning technique without sentiment dictionaries. The importance of developing sentiment dictionaries is declined gradually. However, one of recent studies shows that the words in the sentiment dictionary can be used as features of deep learning models, resulting in the sentiment analysis performed with higher accuracy (Teng, Z., 2016). This result indicates that the sentiment dictionary is used not only for sentiment analysis but also as features of deep learning models for improving accuracy. The proposed dictionary can be used as a basic data for constructing the sentiment lexicon of a particular domain and as features of deep learning models. It is also useful to automatically and quickly build large training sets for deep learning models.

A Study on the Tree Surgery Problem and Protection Measures in Monumental Old Trees (천연기념물 노거수 외과수술 문제점 및 보존 관리방안에 관한 연구)

  • Jung, Jong Soo
    • Korean Journal of Heritage: History & Science
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    • v.42 no.1
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    • pp.122-142
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    • 2009
  • This study explored all domestic and international theories for maintenance and health enhancement of an old and big tree, and carried out the anatomical survey of the operation part of the tree toward he current status of domestic surgery and the perception survey of an expert group, and drew out following conclusion through the process of suggesting its reform plan. First, as a result of analyzing the correlation of the 67 subject trees with their ages, growth status. surroundings, it revealed that they were closely related to positional characteristic, damage size, whereas were little related to materials by fillers. Second, the size of the affected part was the most frequent at the bough sheared part under $0.09m^2$, and the hollow size by position(part) was the biggest at 'root + stem' starting from the behind of the main root and stem As a result of analyzing the correlation, the same result was elicited at the group with low correlation. Third, the problem was serious in charging the fillers (especially urethane) in the big hollow or exposed root produced at the behind of the root and stem part, or surface-processing it. The benefit by charging the hollow part was analyzed as not so much. Fourth, the surface-processing of fillers currently used (artificial bark) is mainly 'epoxy+woven fabric+cork', but it is not flexible, so it has brought forth problems of frequent cracks and cracked surface at the joint part with the treetextured part. Fifth, the correlation with the external status of the operated part was very high with the closeness, surface condition, formation of adhesive tissue and internal survey result. Sixth, the most influential thing on flushing by the wrong management of an old and big tree was banking, and a wrong pruning was the source of the ground part damage. In pruning a small bough can easily recover itself from its damage as its formation of adhesive tissue when it is cut by a standard method. Seventh, the parameters affecting the times of related business handling of an old and big tree are 'the need of the conscious reform of the manager and related business'. Eighth, a reform plan in an institutional aspect can include the arrangement of the law and organization of the old and big tree management and preservation at an institutional aspect. This study for preparing a reform plan through the status survey of the designated old and big tree, has a limit inducing a reform plan based on the status survey through individual research, and a weak point suggesting grounds by any statistical data. This can be complemented by subsequent studies.