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The Actual State and Improvement Proposal for Shading Structures in Korean Ginseng Fields (인삼재배시설의 실태 및 개선방안)

  • Nam, Sang-Woon
    • Journal of Bio-Environment Control
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    • v.12 no.3
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    • pp.114-120
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    • 2003
  • In order to provide fundamental data for development of controlled environment facilities in Korean ginseng (Panax ginseng C.A. Meyer) cultivation, field survey and analysis of structural and environmental engineering characteristics on the shading structures in ginseng fields (the ginseng houses) were carried out. In this study shading structures for ginseng cultivation were classified according to their structural materials, connection types, and detailed structures. That is they were classified into wood or steel frames, single or multi spans, and frame or cable types. As a result of the investigation, standardization of structural materials, fabrication and construction methods arc required. And it was considered that a reinforced design and a countermeasure for heavy snow are the most important matters for structural improvement. In parts of the environmental management, researches for setting up the irrigation standard are required in the first place. And it was investigated that an installation of the shading structures is a work being the most hard, taking a lot of time, and having need for automation. So controlled environment ginseng houses, with a low cost, a structural safety and a satisfactory workability, should be developed.

Selection of Postweld Heat Treatment Condition of a High-Temperature and High-Pressure Forged Valve (고온고압용 단조밸브의 용접후열처리 조건 선정)

  • Park, Jae-Seong;Heo, Ki-Moo;Yoon, Sung-Hoon;Moon, Yoon-Jae;Lee, Jae-Heon
    • Plant Journal
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    • v.10 no.2
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    • pp.48-59
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    • 2014
  • Coupons which have same figure as weld joint of the forged steel valves and 1 inch nominal weld thickness were manufactured using ASTM A182 F92 material. After welding with GTAW method, the welded specimens have been post-weld heat treated at $705^{\circ}C$, $735^{\circ}C$, $750^{\circ}C$, $765^{\circ}C$, $795^{\circ}C$ and $825^{\circ}C$ for 1 hour per 1 inch nominal weld thickness each (Group 1) to evaluate characteristics of welds based on various holding temperature. Indeed, 3 welded specimens were post-weld heat treated for 30 minutes, 1 hour and 2 hour (Group 2) at $735^{\circ}C$ to evaluate characteristics of welds based on various holding time. Hardness values were measured at the weld metal, heat affected zone and base metal to observe hardness change depending on the condition. As a result of the evaluation, appropriate holding temperature for PWHT is proved as $750^{\circ}C$ and $765^{\circ}C$ for 1hour per 1 inch nominal weld thickness. Indeed, holding for 1 hour per 1 inch nominal weld thickness was insufficient for PWHT effect when the holding temperature was at $735^{\circ}C$. The microstructure of post-weld heat treated weld metal was determined as tempered-martensite structure.

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Three body problem in early 20th century (20세기초의 삼체문제에 관해서)

  • Lee, Ho Joong
    • Journal for History of Mathematics
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    • v.25 no.4
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    • pp.53-67
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    • 2012
  • Today, it is necessary to calculate orbits with high accuracy in space flight. The key words of Poincar$\acute{e}$ in celestial mechanics are periodic solutions, invariant integrals, asymptotic solutions, characteristic exponents and the non existence of new single-valued integrals. Poincar$\acute{e}$ define an invariant integral of the system as the form which maintains a constant value at all time $t$, where the integration is taken over the arc of a curve and $Y_i$ are some functions of $x$, and extend 2 dimension and 3 dimension. Eigenvalues are classified as the form of trajectories, as corresponding to nodes, foci, saddle points and center. In periodic solutions, the stability of periodic solutions is dependent on the properties of their characteristic exponents. Poincar$\acute{e}$ called bifurcation that is the possibility of existence of chaotic orbit in planetary motion. Existence of near exceptional trajectories as Hadamard's accounts, says that there are probabilistic orbits. In this context we study the eigenvalue problem in early 20th century in three body problem by analyzing the works of Darwin, Bruns, Gyld$\acute{e}$n, Sundman, Hill, Lyapunov, Birkhoff, Painlev$\acute{e}$ and Hadamard.

Study on the Epidemiological Features of Lyme Disease in Korea between 2011 and 2018 (2011~2018년 라임병의 역학적 특성 연구)

  • Seo, Choong Won
    • Korean Journal of Clinical Laboratory Science
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    • v.51 no.4
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    • pp.436-443
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    • 2019
  • Lyme disease is a national notifiable infectious disease as of September 2018. The number of cases of Lyme disease has recently been increasing. This study analyzed the epidemiological features and clinical symptoms of domestic and imported. From 2011 to December 31, 2018, of the 119 cases, 48 confirmed cases, 63 probable cases, and 8 suspected cases. 70 cases (58.8%) were reported in Korea and 49 cases (41.2%) of imported. In addition, 91 cases (76.5%) were reported during the summer~autumn season (June~November). In 2017, the highest number of 31 cases. The time needed to make a diagnosis was 2.8±14.7 days for domestic occurrences versus 1.4±4.5 days for those cases that infection occurred imported. Among the clinical symptoms, fever and rash were statistically significant (P<0.001). Clinical trials included early localized 31 cases (52.1%), early disseminated 43 cases (35.3%), and late disseminated 15 cases (12.6%). The estimated regions of infection in Korea were Chungnam 12 cases (17.1%), Gyeonggi 12 cases (17.1%), and Gangwon 8 cases (11.4%), Patient care is also considered to be very important as this disease occurs of all ages. Therefore, the promotion of preventive education and identification of epidemiological features are of paramount importance and should be implemented. The study's findings can be used as basic data for the prevention and management of patients with lyme disease.

Production Technology of Titanium by Kroll Process (Kroll법에 의한 타이타늄의 제조기술)

  • Sohn, Ho-Sang
    • Resources Recycling
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    • v.29 no.4
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    • pp.3-14
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    • 2020
  • Titanium sponge is industrially produced by the Kroll process. In order to understand the importance of the emerging smelting and recycling process, it is necessary to review the conventional production process of titanium. Therefore this paper provides a general overview of the conventional titanium manufacturing system mainly by the Kroll process. The Kroll process can be divided into four sub-processes as follows: (1) Chlorination of raw TiO2 with coke, by the fluidized bed chlorination or molten salt chlorination (2) Magnesium reduction of TiCl4 and vacuum distillation of MgCl2 and Mg by reverse U-type or I-type with reduction-distillation integrated retorts (3) Electrolysis process of MgCl2 by monopolar cells or multipolar cells to electrolyze into chlorine gas and Mg. (4) Crushing and melting process in which sponge titanium is crushed and then melted in a vacuum arc furnace or an electron beam furnace Although the apparatus and procedures have improved over the past 80 years, the Kroll process is the costly and time-consuming batch operation for the reduction of TiCl4 and the separation of MgCl2.

The Sixteen Arhat Images of the Koryo Period at Sungbul-sa, Chunan (천안 성불사 고려시대 마애십육나한상 (天安 成佛寺 高麗時代 磨崖十六羅漢像))

  • Choe, Seong-Eun
    • Korean Journal of Heritage: History & Science
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    • v.33
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    • pp.162-181
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    • 2000
  • This paper investigates sixteen rock-cut arhat images of the Koryo period at Sungbul-sa (成佛寺) in Chunan (天安), South Chungchung Province. These images, together with a Buddha triad in the center, are carved in thin relief on the large granite wall ($375cm{\times}248cm$), and below them is engraved a huge lotus petal which looks to be supporting all the images above. According to extant textual sources, arhats were popularly worshipped in the Koryo period. The Painting of Five Hundred Arhat Images was brought to Koryo from Later Liang (後梁) of the Five Dynasties (五代) in 923. From that time on, the cult of arhat had become gradually known in Koryo. More than thirty ceremonies worshipping arhats (羅漢齊) were officially held in Koryo court. The Sixteen Arhat images (十六羅漢像) were enshrined in many temples. In Boje-sa (普濟寺), which kings and aristocrats often visited for ritual ceremonies, had its main hall dominated by the Five Hundred Arhats, called Nahan-pocheon (羅漢寶殿). However, a limited number of arhat images of the Koryo period, originally made as sets of sixteen or five hundred arhats, are now extant. The Sixteen Arhat images at Sungbul-sa are unique examples that show all sixteen images in situ. The Sixteen Arhat images, though some of them are abraded, show various postures and gesture. One of them sits with his knee bent, and one arhat is sitting on a chair with his hand held upward. Each image is carved in a niche, just as the arhat images of Northern Song China are normally represented in niches of a cave, and are quite similar in style to the arhat images of the Northern Song period at Qinglindong (靑林洞) cave, Feilaifeng (飛來峰), Zejiang province (浙江省). This similarity between the arhat images of Sungbul-sa and those of Qinglindong certifies the strong impact of Song Buddhist art on Koryo frequently mentioned in texts. The Sixteen Arhat images surround the central Buddha raising his hand up to his chest. This Buddha triad could be ascribed to be either the Maitreya Buddha triad or the Sakyamuni Buddha triad based on the Lotus Sutra (妙法蓮華經). Still, the Sakyamuni Buddha triad was more often represented with sixteen or five hundred arhats in the Koryo period, as was seen in the record of Boje-sa where the Sakyamuni triad was enshrined with five hundred arhat images. The Sixteen Arhat images of Sungbul-sa arc most likely to be a rare example of Koryo Arhat images showing the Sakyamuni Buddha triad and the Sixteen Arhats who were predicted to be Buddhas by Sakyamuni in the Lotus Sutra.

Path Algorithm for Maximum Tax-Relief in Maximum Profit Tax Problem of Multinational Corporation (다국적기업 최대이익 세금트리 문제의 최대 세금경감 경로 알고리즘)

  • Sang-Un Lee
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.23 no.4
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    • pp.157-164
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    • 2023
  • This paper suggests O(n2) polynomial time heuristic algorithm for corporate tax structure optimization problem that has been classified as NP-complete problem. The proposed algorithm constructs tax tree levels that the target holding company is located at root node of Level 1, and the tax code categories(Te) 1,4,3,2 are located in each level 2,3,4,5 sequentially. To find the maximum tax-relief path from source(S) to target(T), firstly we connect the minimum witholding tax rate minrw(u, v) arc of node u point of view for transfer the profit from u to v node. As a result we construct the spanning tree from all of the source nodes to a target node, and find the initial feasible solution. Nextly, we find the alternate path with minimum foreign tax rate minrfi(u, v) of v point of view. Finally we choose the minimum tax-relief path from of this two paths. The proposed heuristic algorithm performs better optimal results than linear programming and Tabu search method that is a kind of metaheuristic method.

Transcriptomic Profile in Pear Leave with Resistance Against Venturia nashicola Infection (배 검은별무늬병 감염과 저항성 방어반응 연관 전사체 프로파일)

  • Il Sheob Shin;Jaean Chun;Sehee Kim;Kanghee Cho;Kyungho Won;Haewon Jung;Keumsun Kim
    • Proceedings of the Plant Resources Society of Korea Conference
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    • 2022.09a
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    • pp.36-36
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    • 2022
  • The molecular understanding of resistance and susceptibility of host plants to scab, a most threatful disease to pome fruit production worldwide, is very limited. Comparing resistant line '93-3-98' to susceptible one 'Sweet Skin' at seven time points of 0, 0.5, 1, 2, 3, 4, 8 days post inoculation, RNA-sequencing data derived from infected and mock-inoculated young leaves were analyzed to evaluate the tolerant response and to mine candidate genes of pear to the scab pathogen Venturia nashicola. Analysis of the mapped reads showed that the infection of V. nashicola led to significant differential expression of 17,827 transcripts with more than 3-fold change in the seven pairs of libraries, of which 9,672 (54%) are up- and 8,155(46%) are down-regulated. These included mainly receptor (NB-ARC domains-containing, CC-NBS-LRR, TIR-NBS-LRR, seven transmembrane MLO family protein) and transcription factor (ethylene responsive element binding, WRKY DNA-binding protein) related gene. An arsenal of defense response of highly resistant pear accessions derived from European pear was probably supposed no sooner had V. nashicola infected its host than host genes related to disease suppression like Polyketide cyclase/dehydrase and lipid transport protein, WRKY family transcription factor, lectin protein kinase, cystein-rich RLK, calcium-dependent phospholipid-binding copine protein were greatly boosted and eradicated cascade reaction induced by pathogen within 24 hours. To identify transcripts specifically expressed in response to V. nashicola, RT-PCRs were conducted and compare to the expression patterns of seven cultivars with a range of highly resistant to highly susceptible symptom. A DEG belonging to the PR protein family genes that were higher expressed in response to V. nashicola suggesting extraordinary role in the resistance response were led to the identification. This study provides the first transcriptional profile by RNA-seq of the host plant during scab disease and insights into the response of tolerant pear plants to V. nashicola.

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Cluster exploration of water pipe leak and complaints surveillance using a spatio-temporal statistical analysis (스캔통계량 분석을 통한 상수도 누수 및 수질 민원 발생 클러스터 탐색)

  • Juwon Lee;Eunju Kim;Sookhyun Nam;Tae-Mun Hwang
    • Journal of Korean Society of Water and Wastewater
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    • v.37 no.5
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    • pp.261-269
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    • 2023
  • In light of recent social concerns related to issues such as water supply pipe deterioration leading to problems like leaks and degraded water quality, the significance of maintenance efforts to enhance water source quality and ensure a stable water supply has grown substantially. In this study, scan statistic was applied to analyze water quality complaints and water leakage accidents from 2015 to 2021 to present a reasonable method to identify areas requiring improvement in water management. SaTScan, a spatio-temporal statistical analysis program, and ArcGIS were used for spatial information analysis, and clusters with high relative risk (RR) were determined using the maximum log-likelihood ratio, relative risk, and Monte Carlo hypothesis test for I city, the target area. Specifically, in the case of water quality complaints, the analysis results were compared by distinguishing cases occurring before and after the onset of "red water." The period between 2015 and 2019 revealed that preceding the occurrence of red water, the leak cluster at location L2 posed a significantly higher risk (RR: 2.45) than other regions. As for water quality complaints, cluster C2 exhibited a notably elevated RR (RR: 2.21) and appeared concentrated in areas D and S, respectively. On the other hand, post-red water incidents of water quality complaints were predominantly concentrated in area S. The analysis found that the locations of complaint clusters were similar to those of red water incidents. Of these, cluster C7 exhibited a substantial RR of 4.58, signifying more than a twofold increase compared to pre-incident levels. A kernel density map analysis was performed using GIS to identify priority areas for waterworks management based on the central location of clusters and complaint cluster RR data.

Story-based Information Retrieval (스토리 기반의 정보 검색 연구)

  • You, Eun-Soon;Park, Seung-Bo
    • Journal of Intelligence and Information Systems
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    • v.19 no.4
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    • pp.81-96
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    • 2013
  • Video information retrieval has become a very important issue because of the explosive increase in video data from Web content development. Meanwhile, content-based video analysis using visual features has been the main source for video information retrieval and browsing. Content in video can be represented with content-based analysis techniques, which can extract various features from audio-visual data such as frames, shots, colors, texture, or shape. Moreover, similarity between videos can be measured through content-based analysis. However, a movie that is one of typical types of video data is organized by story as well as audio-visual data. This causes a semantic gap between significant information recognized by people and information resulting from content-based analysis, when content-based video analysis using only audio-visual data of low level is applied to information retrieval of movie. The reason for this semantic gap is that the story line for a movie is high level information, with relationships in the content that changes as the movie progresses. Information retrieval related to the story line of a movie cannot be executed by only content-based analysis techniques. A formal model is needed, which can determine relationships among movie contents, or track meaning changes, in order to accurately retrieve the story information. Recently, story-based video analysis techniques have emerged using a social network concept for story information retrieval. These approaches represent a story by using the relationships between characters in a movie, but these approaches have problems. First, they do not express dynamic changes in relationships between characters according to story development. Second, they miss profound information, such as emotions indicating the identities and psychological states of the characters. Emotion is essential to understanding a character's motivation, conflict, and resolution. Third, they do not take account of events and background that contribute to the story. As a result, this paper reviews the importance and weaknesses of previous video analysis methods ranging from content-based approaches to story analysis based on social network. Also, we suggest necessary elements, such as character, background, and events, based on narrative structures introduced in the literature. We extract characters' emotional words from the script of the movie Pretty Woman by using the hierarchical attribute of WordNet, which is an extensive English thesaurus. WordNet offers relationships between words (e.g., synonyms, hypernyms, hyponyms, antonyms). We present a method to visualize the emotional pattern of a character over time. Second, a character's inner nature must be predetermined in order to model a character arc that can depict the character's growth and development. To this end, we analyze the amount of the character's dialogue in the script and track the character's inner nature using social network concepts, such as in-degree (incoming links) and out-degree (outgoing links). Additionally, we propose a method that can track a character's inner nature by tracing indices such as degree, in-degree, and out-degree of the character network in a movie through its progression. Finally, the spatial background where characters meet and where events take place is an important element in the story. We take advantage of the movie script to extracting significant spatial background and suggest a scene map describing spatial arrangements and distances in the movie. Important places where main characters first meet or where they stay during long periods of time can be extracted through this scene map. In view of the aforementioned three elements (character, event, background), we extract a variety of information related to the story and evaluate the performance of the proposed method. We can track story information extracted over time and detect a change in the character's emotion or inner nature, spatial movement, and conflicts and resolutions in the story.