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Design of Multi-agent System for Course Scheduling of Learner-oriented using Weakness Analysis Algorithm (취약성 분석 알고리즘을 이용한 학습자 중심의 코스 스케쥴링 멀티 에이전트 시스템의 설계)

  • Kim, Tae-Seog;Lee, Jong-Hee;Lee, Keun-Wang;Oh, Hae-Seok
    • The KIPS Transactions:PartA
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    • v.8A no.4
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    • pp.517-522
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    • 2001
  • The appearance of web technology has accelerated a role of the development of the multimedia technology, the computer communication technology and the multimedia application contents. And serveral researches of WBI (Web-based Instruction) system have combined the technology of the digital library and LOD. Recently WBI (Web-based Instruction) model which is based on web has been proposed in the part of the new activity model of teaching-learning. And the demand of the customized coursewares which is required from the learners is increased, the needs of the efficient and automated education agents in the web-based instruction are recognized. But many education systems that had been studied recently did not service fluently the courses which learners had been wanting and could not provide the way for the learners to study the learning weakness which is observed in the continuous feedback of the course. In this paper we propose "Design of Multi-agent System for Course Scheduling of Learner-oriented using Weakness Analysis Algorithm". First proposed system monitors learner's behaviors constantly, evaluates them, and calculates his accomplishment. From this accomplishment the multi-agent schedules the suitable course for the learner. And the learner achieves a active and complete learning from the repeated and suitable course.le course.

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Effect of Foundation Flexibility of Offshore Wind Turbine on Force and Movement at Monopile Head (해상풍력발전기 기초구조물의 강성이 모노파일 두부의 부재력 및 변위에 미치는 영향)

  • Jung, Sungmoon;Kim, Sung-Ryul;Lee, Juhyung;Le, Chi Hung
    • Journal of the Korean Geosynthetics Society
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    • v.13 no.4
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    • pp.21-31
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    • 2014
  • Recently, the research on renewable energy against depletion of fossil fuel have been actively carried out in the world. Especially, offshore wind turbines are very economical and innovative technology. However, offshore wind turbines experience large base moments due to the wind and wave loading, so the monopile with large diameter needs to be applied. For the economical design of the large diameter pile, it is important to consider the flexibility of the foundation to estimate the maximum moment accurately, based on studies conducted so far. In this paper, the foundation was modeled using the finite element method in order to better describe the large diameter effect of a monopile and the results were compared with those of p-y method. For the examples studied in this paper, the change in maximum moment was insignificant, but the maximum tilt angle from the finite element method was over 14% larger than that of p-y method. Therefore, the finite element approach is recommended to model the flexibility effect of the pile when large tilt angles may cause serviceability issues.

Simulation of reactivity-initiated accident transients on UO2-M5® fuel rods with ALCYONE V1.4 fuel performance code

  • Guenot-Delahaie, Isabelle;Sercombe, Jerome;Helfer, Thomas;Goldbronn, Patrick;Federici, Eric;Jolu, Thomas Le;Parrot, Aurore;Delafoy, Christine;Bernaudat, Christian
    • Nuclear Engineering and Technology
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    • v.50 no.2
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    • pp.268-279
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    • 2018
  • The ALCYONE multidimensional fuel performance code codeveloped by the CEA, EDF, and AREVA NP within the PLEIADES software environment models the behavior of fuel rods during irradiation in commercial pressurized water reactors (PWRs), power ramps in experimental reactors, or accidental conditions such as loss of coolant accidents or reactivity-initiated accidents (RIAs). As regards the latter case of transient in particular, ALCYONE is intended to predictively simulate the response of a fuel rod by taking account of mechanisms in a way that models the physics as closely as possible, encompassing all possible stages of the transient as well as various fuel/cladding material types and irradiation conditions of interest. On the way to complying with these objectives, ALCYONE development and validation shall include tests on $PWR-UO_2$ fuel rods with advanced claddings such as M5(R) under "low pressure-low temperature" or "high pressure-high temperature" water coolant conditions. This article first presents ALCYONE V1.4 RIA-related features and modeling. It especially focuses on recent developments dedicated on the one hand to nonsteady water heat and mass transport and on the other hand to the modeling of grain boundary cracking-induced fission gas release and swelling. This article then compares some simulations of RIA transients performed on $UO_2$-M5(R) fuel rods in flowing sodium or stagnant water coolant conditions to the relevant experimental results gained from tests performed in either the French CABRI or the Japanese NSRR nuclear transient reactor facilities. It shows in particular to what extent ALCYONE-starting from base irradiation conditions it itself computes-is currently able to handle both the first stage of the transient, namely the pellet-cladding mechanical interaction phase, and the second stage of the transient, should a boiling crisis occur. Areas of improvement are finally discussed with a view to simulating and analyzing further tests to be performed under prototypical PWR conditions within the CABRI International Program. M5(R) is a trademark or a registered trademark of AREVA NP in the USA or other countries.

High rate deposition of poly-si thin films using new magnetron sputtering source

  • Boo, Jin-Hyo;Park, Heon-Kyu;Nam, Kyung-Hoon;Han, Jeon-Geon
    • Proceedings of the Korean Vacuum Society Conference
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    • 2000.02a
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    • pp.186-186
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    • 2000
  • After LeComber et al. reported the first amorphous hydrogenated silicon (a-Si: H) TFT, many laboratories started the development of an active matrix LCDs using a-Si:H TFTs formed on glass substrate. With increasing the display area and pixel density of TFT-LCD, however, high mobility TFTs are required for pixel driver of TF-LCD in order to shorten the charging time of the pixel electrodes. The most important of these drawbacks is a-Si's electron mobiliy, which is the speed at which electrons can move through each transistor. The problem of low carier mobility for the a-Si:H TFTs can be overcome by introducing polycrystalline silicon (poly-Si) thin film instead of a-Si:H as a semiconductor layer of TFTs. Therefore, poly-Si has gained increasing interest and has been investigated by many researchers. Recnetly, fabrication of such poly-Si TFT-LCD panels with VGA pixel size and monolithic drivers has been reported, . Especially, fabricating poly-Si TFTs at a temperature mach lower than the strain point of glass is needed in order to have high mobility TFTs on large-size glass substrate, and the monolithic drivers will reduce the cost of TFT-LCDs. The conventional methods to fabricate poly-Si films are low pressure chemical vapor deposition (LPCVD0 as well as solid phase crystallization (SPC), pulsed rapid thermal annealing(PRTA), and eximer laser annealing (ELA). However, these methods have some disadvantages such as high deposition temperature over $600^{\circ}C$, small grain size (<50nm), poor crystallinity, and high grain boundary states. Therefore the low temperature and large area processes using a cheap glass substrate are impossible because of high temperature process. In this study, therefore, we have deposited poly-Si thin films on si(100) and glass substrates at growth temperature of below 40$0^{\circ}C$ using newly developed high rate magnetron sputtering method. To improve the sputtering yield and the growth rate, a high power (10~30 W/cm2) sputtering source with unbalanced magnetron and Si ion extraction grid was designed and constructed based on the results of computer simulation. The maximum deposition rate could be reached to be 0.35$\mu$m/min due to a high ion bombardment. This is 5 times higher than that of conventional sputtering method, and the sputtering yield was also increased up to 80%. The best film was obtained on Si(100) using Si ion extraction grid under 9.0$\times$10-3Torr of working pressure and 11 W/cm2 of the target power density. The electron mobility of the poly-si film grown on Si(100) at 40$0^{\circ}C$ with ion extraction grid shows 96 cm2/V sec. During sputtering, moreover, the characteristics of si source were also analyzed with in situ Langmuir probe method and optical emission spectroscopy.

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Analysis of Soil Erosion and Sediment Yields at the Doam-dam Watershed considering Soil Properties from the Soil Reconditioned Agricultural Fields using SATEEC System (SATEEC 시스템을 이용한 객토 토양의 토성고려에 따른 도암댐 유역의 토양유실 및 유사량 분석)

  • Yoo, Dongsun;Ahn, Jaehun;Yoon, Jongsuk;Heo, Sunggu;Park, Younshik;Kim, Jonggun;Lim, Kyoung Jae;Kim, Ki-sung
    • Journal of Korean Society on Water Environment
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    • v.23 no.4
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    • pp.518-526
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    • 2007
  • There have been serious soil erosion and water pollution problems caused by highland agriculture practices at Doam-dam watershed. Especially agricultural activities, chemical and organic fertilizer and pesticide applications, soil reconditioning to maintain soil fertility are known as primary causes of soil erosion and water qaulity degradation in the receiving water bodies. Among these, soil reconditioning can accelerate soil erosion rates. To develop soil erosion prevention practices, it is necessary to estimate the soil erosion from the watershed. Thus, the Universal Soil Loss Equation (USLE) model has been developed and utilized to assess soil erosion. However, the USLE model cannot be used at watershed scale because it does not consider sediment delivery ratio (SDR) for watershed application. For this reason, the Sediment Assessment Tool for Effective Erosion Control (SA TEEC) was developed to assess the sediment yield at any point in the watershed. The USLE-based SA TEEC system can estimate the SDR using area-based SDR and slope-based SDR module. In this study, the SATEEC system was used to estimate soil erosion and sediment yield at the Doam-dam watershed using the soil properties from reconditioned agricultural fields. Based on the soil sampling and analysis, the US LE K factor was calculated and used in the SA TEEC system to analyze the possible errors of previous USLE application studies using soil properties from the digital soil map, and compared with that using soil properties obtained in this study. The estimated soil erosion at the Doam-dam watershed without using soil properties obtained in the soil sampling and analysis is 1,791,400 ton/year (123 ton/ha/year), while the soil erosion amount is 2,429,900 ton/year (166.8 ton/ha/year) with the use of soil properties from the soil sampling and analysis. There is 35 % increase in estimated soil erosion and sediment yield with the use of soil properties from soil reconditioned agricultural fields. Since significant amount of soil erosion are known to be occurring from the agricultural fields, the soil erosion and sediment yield from only agricultural fields was assessed. The soil erosion rate is 45.9 ton/ha/year without considering soil properties from soil reconditioned agricultural fields, while 105.3 ton/ha/year after considering soil properties obtained in this study, increased in 129%. This study shows that it is very important to use correct soil properties to assess soil erosion and sediment yield simulation. It is recommended that further studies are needed to develop environment friendly soil reconditioning method should be developed and implemented to decrease the speed of soil erosion rates and water quality degradation.

Partial Characterization of Two Cathepsin D Family Aspartic Peptidases of Clonorchis sinensis

  • Kang, Jung-Mi;Yoo, Won-Gi;Le, Huong Giang;Thai, Thi Lam;Hong, Sung-Jong;Sohn, Woon-Mok;Na, Byoung-Kuk
    • Parasites, Hosts and Diseases
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    • v.57 no.6
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    • pp.671-680
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    • 2019
  • Cathepsin D (CatD, EC 3.4.23.5) is a member belonging to the subfamily of aspartic endopeptidases, which are classified into the MEROPS clan AA, family A1. Helminth parasites express a large set of different peptidases that play pivotal roles in parasite biology and pathophysiology. However, CatD is less well known than the other classes of peptidases in terms of biochemical properties and biological functions. In this study, we identified 2 novel CatDs (CsCatD1 and CsCatD2) of Clonorchis sinensis and partially characterized their properties. Both CsCatDs represent typical enzymes sharing amino acid residues and motifs that are tightly conserved in the CatD superfamily of proteins. Both CsCatDs showed similar patterns of expression in different developmental stages of C. sinensis, but CsCatD2 was also expressed in metacercariae. CsCatD2 was mainly expressed in the intestines and eggs of C. sinensis. Sera obtained from rats experimentally infected with C. sinensis reacted with recombinant CsCatD2 beginning 2 weeks after infection and the antibody titers were gradually increased by maturation of the parasite. Structural analysis of CsCatD2 revealed a bilobed enzyme structure consisting of 2 antiparallel β-sheet domains packed against each other forming a homodimeric structure. These results suggested a plausible biological role of CsCatD2 in the nutrition and reproduction of parasite and its potential utility as a serodiagnostic antigen in clonorchiasis.

A Biomechanical Analysis of an Interspinous Distraction Device for Treatment of Lumbar Spinal Stenosis (요추부 협착증 치료를 위한 극돌기 삽입술의 생체역학적 효과 분석)

  • Lee Hui-Sung;Chen Wen Ming;Song Dong-Ryul;Kwon Soon-Young;Lee Kwon-Yong;Lee Sung-Jae
    • Journal of Biomedical Engineering Research
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    • v.27 no.5
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    • pp.210-217
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    • 2006
  • Many types of interspinous distraction devices (IDDs) have been recently developed as an alternative surgical treatment to laminectomy and fusion with pedicle screws for the treatment of the lumbar spinal stenosis (LSS). They are intended to keep the lumbar spine in a slightly flexed posture to relieve pain caused by narrowing of the spinal canal and vertebral foramen. However, their biomechanical efficacies are not well known. In this study, we evaluated the kinematic behaviors and changes in intradiscal pressure (IDP) of the porcine lumbar spine implanted with IDD. For kinematics analysis, five porcine lumbar spines (L2-L6) were used and the IDD was inserted at L4-L5. Three markers (${\phi}{\le}0.8mm$) were attached on each vertebra to define a rigid body motion for stereophotogrammetric assessment of the spinal motion in 3-D. A moment of 7.5Nm in flexion-extension, lateral bending, and axial rotation were imparted with a compressive force of 700N. Then, IDD was implanted at L3-L4. IDPs were measured using pressure transducer under compression (700N) and additional extension moment (700N+7.5Nm). In kinematic behaviors, insertion of IDD resulted in statistically significant decrease 42.8% at the implanted level in extension. There were considerable changes in ROM at the adjacent levels, but statistically insignificant. In other motions, there were no significant changes in ROM as well regardless of levels. IDPs at the surgical level (L3-L4) under compression and extension moment decreased by 12.9% and 18.8% respectively after surgery (p<0.05). At the superiorly adjacent levels, IDPs increased by 19.4% and 12.9% under compression and extension, respectively (p<0.05). Corresponding changes at the inferiorly adjacent levels were 29.4% and 6.9%, but they were statistically insignificant (p>0.05). The magnitude of pressure changes due to IDD, both at the operated and adjacent levels, were far less than the previously reported values with conventional fusion techniques. Our experimental results demonstrated the IDDs can be very effective in limiting the extension motion that may cause narrowing of the spinal canal and vertebral foramens while maintaining kinematic behaviors and disc pressures at the adjacent levels.

Research on the Modification of Folktales' Motifs (민담 모티프의 변용 양상 연구 - 러시아 요술담의 바바야가를 중심으로)

  • Chun, Seonghee
    • Cross-Cultural Studies
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    • v.39
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    • pp.241-286
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    • 2015
  • This study explores how folktales' motifs are used in diverse cultural contents such as literature, movies, or comics. More precisely, it is concerned with mysterious characters like Babayaga and Koshchei who appear in Russian fairytales. When the motifs of the reviewed literature are analyzed, the following three criteria are used for classification: New Writing, Rewriting, and New Version. Or course, it is New Writing that is far from the original work. Most of the collected works, including Joan Aiken's The Kingdom Under the Sea, Patricia Polacco's Babushka's Doll, Babushka Baba Yaga, and Tai?-Marc Le Thanh's BABAYAGA, belong to New Writing. The New Writing type mainly focuses on Babayaga's secluded life. In fairytales, Babayaga is depicted as the goddess of Mother Earth, the heroine of the Nature, or the ruler of the Animal Kingdom. That is why she lives in the deep and uninhabited wood. She is related to the Coming of Age ceremony. Her 'Hut on hen's legs' is an obstacle for immature protagonists to face before they come of age. Protagonists are supposed to solve the problems posed by Babayaga. If they succeed, they can get her magical help so as to complete their final mission. Babayaga is likely to appear as their antagonist. Protagonist may be subjected to a terrible ordeal created by Babayaga, and then come of age by recovering from that ordeal. Sometimes, Babayaga helps protagonists to get a grip on reality. That is why she lives in a hut in the deep and dark forest which is on the borderline between life and death. On the other hand, Marianna Mayer's Baba Yaga and Vasilisa the Brave has been classified as a controversial work between New Writing and Rewriting. It is apparently closer to New Version. However, it cannot be classified as a work of New Version because the author incorporates 'probability' into her work. Among the reviewed works, it is Korean Writer Rye, Kami's The Spider Woman's House that best reflects the essence of Babayaga. Babayaga and other characters are amusing in movies because most of the movies are animations for children. In one sense, it is positive that the scary characters in folktales are approachable to children. In other sense, however, it is regrettable that symbolic motifs are completely eliminated. In Mike Mignola's Hellboy, Japanese animations such as Index or Narutaru, on-line games such as Cabal or Vampire: The masquerade, the essence of the supernatural characters in folktales is completely eliminated, and only their 'belligerent power' stands out. It is desirable to put stories into perspective whether they are written or told. The literature property of folktales provides a special opportunity to readers. In this light, a variety of motifs have a good reason to be reborn as modern cultural contents. The bottom line is to maintain its true nature.

The Re-inspection on The Explanatory Model ofXi Ming of Chu Hsi'sThought of "Li Yi Fen Shu" (朱熹 「理一分殊」 的 <西銘> 詮釋模式再考察)

  • Lin, Le-chang
    • Journal of Korean Philosophical Society
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    • v.141
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    • pp.167-185
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    • 2017
  • Chu Hsi inherited the proposition of Cheng Yi, and it spent him over ten years to finish writing the works of Xi Ming Jie, thus, making the thought of "Li Yi Fen Shu" bethe explanatory model of Xi Ming, therefore, playing the role to determine the tone of Xi Ming. At first, the thought of "Li Yi Fen Shu is a concept to embody the ethical significance of Xi Ming. But in terms of all the discussion about "Li Yi Fen Shu" of Chu Hsi in his life, this proposition is not only for the ethical significance of Xi Ming, but also includes much more general philosophical significance, revealing the general and special relationship of things. The former is the narrow "Li Yi Fen Shu", but the latter is the generalized one. This article won't discuss the generalized one, and it will take the narrow one as the research object. In the past research in academic circles, some scholars thinks that the proposition of "Li Yi Fen Shu" accords with the aim of Xi Ming, some others don't think so. Contrary to both of the two views, this article thinks that there is some conformity and inconformity between the explanatory model of "Li Yi Fen Shu" of Chu Hsi and the aim of Xi Ming. In other words, Contributions and limitations coexist when Chu Hsi explains Xi Ming in the model of "Li Yi Fen Shu", and there is not only the development to the intention of Xi Ming, but alsothe far meaning away from the aim of Xi Ming.

Quantifying the effects of climate variability and human activities on runoff for Vugia - Thu Bon River Basin in Central of Viet Nam

  • Lan, Pham Thi Huong;Thai, Nguyen Canh;Quang, Tran Viet;Long, Ngo Le
    • Proceedings of the Korea Water Resources Association Conference
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    • 2015.05a
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    • pp.233-233
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    • 2015
  • Vu Gia - Thu Bon basin is located in central Vietnam between Truong Son mountain range on the border with Lao in the west and the East Sea in the east. The basin occupies about 10,350 km2 or roughly 90% of the Quang Nam Province and includes Da Nang, a very large city with about 876,000 inhabitants. Total annual rainfall ranges from about 2,000 mm in central and downstream areas to more than 4,000 mm in southern mountainous areas. Rainfall during the monsoon season accounts for 65 to 80% of total annual rainfall. The highest amount of rainfall occurs in October and November which accounts for 40 to 50% of the annual rainfall. Rainfall in the dry season represents about 20 to 35% of the total annual rainfall. The low rainfall season usually occurs from February to April, accounting for only 3 to 5% of the total annual rainfall. The mean annual flow volume in the basin is $19.1{\times}109m 3$. Similar to the distribution of rainfall, annual flows are distinguished by two distinct seasons (the flood season and the low-flow season). The flood season commonly starts in the mid-September and ends in early January. Flows during the flood season account for 62 to 69% of the total annual water volume, while flows in the dry season comprise 22 to 38% of total annual run-off. The water volume gauged in November, the highest flow month, accounts for 26 to 31% of the total annual run-off while the driest period is April with flows of 2 to 3% of the total annual run-off. There are some hydropower projects in the Vu Gia - Thu Bon basin as the cascade of Song Bung 2, Song Bung 4, and Song Bung 5, the A Vuong project currently under construction, the Dak Mi 1 and Dak Mi 4 projects on the Khai tributary, and the Song Con project on the Con River. Both the Khai tributary and the Song Con join the Bung River downstream of SB5, although the Dak Mi 4 project involves an inter-basin diversion to Thu Bon. Much attention has recently been focused on the effects that climate variability and human activities have had on runoff. In this study, data from the Vu Gia - Thu Bon River Basin in the central of Viet Nam were analyzed to investigate changes in annual runoff during the period of 1977-2010. The nonparametric Mann-Kendall test and the Mann-Kendall-Sneyers test were used to identify trend and step change point in the annual runoff. It was found that the basin had a significant increasing trend in annual runoff. The hydrologic sensitivity analysis method was employed to evaluate the effects of climate variability and human activities on mean annual runoff for the human-induced period based on precipitation and potential evapotranspiration. This study quantitatively distinguishes the effects between climate variability and human activities on runoff, which can do duty for a reference for regional water resources assessment and management.

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