• Title/Summary/Keyword: semi-active

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Stereoscopic Free-viewpoint Tour-Into-Picture Generation from a Single Image (단안 영상의 입체 자유시점 Tour-Into-Picture)

  • Kim, Je-Dong;Lee, Kwang-Hoon;Kim, Man-Bae
    • Journal of Broadcast Engineering
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    • v.15 no.2
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    • pp.163-172
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    • 2010
  • The free viewpoint video delivers an active contents where users can see the images rendered from the viewpoints chosen by them. Its applications are found in broad areas, especially museum tour, entertainment and so forth. As a new free-viewpoint application, this paper presents a stereoscopic free-viewpoint TIP (Tour Into Picture) where users can navigate the inside of a single image controlling a virtual camera and utilizing depth data. Unlike conventional TIP methods providing 2D image or video, our proposed method can provide users with 3D stereoscopic and free-viewpoint contents. Navigating a picture with stereoscopic viewing can deliver more realistic and immersive perception. The method uses semi-automatic processing to make foreground mask, background image, and depth map. The second step is to navigate the single picture and to obtain rendered images by perspective projection. For the free-viewpoint viewing, a virtual camera whose operations include translation, rotation, look-around, and zooming is operated. In experiments, the proposed method was tested eth 'Danopungjun' that is one of famous paintings made in Chosun Dynasty. The free-viewpoint software is developed based on MFC Visual C++ and OpenGL libraries.

Inhibition of α-Glucosidase by a Semi-Purified Ethyl Acetate Fraction from Submerged-Liquid Culture of Agaricus blazei Murill (신령버섯균사체 액체배양물의 α-glucosidase 저해 효과)

  • Jung, Kwan-Ju;Moon, Yeon-Gyu;Kwon, Jung-Min;Ahn, Chae-Rin;Kim, Jeong-Ok;Ha, Yeong-Lae
    • Journal of Life Science
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    • v.21 no.11
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    • pp.1579-1585
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    • 2011
  • Natural anti-diabetic semipurified ethyl acetate fraction was isolated from the submerged-liquid culture of Agaricus blaze Murill (AB) in a medium containing soybean flakes. Hot-water extract of AB (HEAB) was prepared by extraction at $121^{\circ}C$ for 60 min, followed by filtering through a filter presser filled with diatomate. The ${\beta}$-glucan-free HEAB, which was a supernatant fraction from HEAB by precipitation in an 80% ethanol solution, was fractionated into hexane, chloroform, ethyl acetate, and butanol fractions. The inhibition of the ${\alpha}$-glucosidase activity by fractions was 59.0, 17.0, 61.6, and 37.9%, respectively, suggesting that ethyl acetate fraction was the most active. A subfraction having a strong ${\alpha}$-glucosidase inhibitory activity (80.4%) was isolated from the ethyl acetate fraction. This subfraction contained isoflavones (genistin and daidzin) and their conjugates with sugars as potent inhibiters of ${\alpha}$-glucosidase activity. These results suggest that the ethyl acetate fraction or HEAB containing isoflavones and their sugars conjugates could be useful sources for controlling blood sugar levels in humans.

Real-time Vibration Control of Bridges by MR damper and Lyapunov Control Algorithm (MR댐퍼 및 Lyapunov제어알고리즘을 이용한 교량 구조물의 실시간 진동제어)

  • Heo, Gwang-Hee;Jeon, Joon-Ryong;Park, Seung-Bum;Oh, Sung-Keun
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.14 no.4
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    • pp.55-61
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    • 2010
  • This paper is concerned with an experimental research to random vibration control caused by external loads specially in bridges which tend to be structurally flexible. Experimenting on a reduced structure modelled on Seohae Grand Bridge, we inflicted a reduced form of El-centro wave on the model structure to a proper proportion. On the center of its middle span, we placed a shear type MR damper which was to control its vibration and also acquire its structural responses such as displacement and acceleration at the same site. The experiments concerning controlling vibration were performed according to a variety of theories including un-control, passive on/off control, and Lyapunov stability theory. Its control performance was evaluated in terms of the peak absolute displacements, the peak absolute accelerations and the total power required to control the bridge which differ from each different experiment method. Among all the methods applied in this paper, case of Lyapunov control method turned out to be the most effective to reduces of displacement and acceleration. Also, this method could to decrease consuming of external power for vibration control. Finally, it was noteworthy that Lyapunov control method was specially effective in the vibration control employing a semi-active damper such MR damper.

Analysis of Pre-service Secondary Science Teachers' Uses of Curriculum Materials in Curriculum Design (중등 예비과학교사의 교육과정 설계에서 교육과정 자료의 활용 방식 분석)

  • Yang, Chanho;Bae, Yujin;Noh, Taehee
    • Journal of The Korean Association For Science Education
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    • v.33 no.7
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    • pp.1312-1328
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    • 2013
  • In this study, we investigated preservice secondary science teachers' uses of curriculum materials in curriculum design through a case study. Two preservice science teachers at a college of education in Seoul participated in this study. We interviewed them about their beliefs on teaching and learning prior to their teaching students. We then observed their teaching and collected all of the teaching/learning materials. Semi-structured interviews were also conducted before and after the instructions. Their uses of curriculum materials were systematically analyzed in the aspects of reading, evaluating and adapting curriculum materials. The analyses of the results revealed that their uses of curriculum materials had a significant difference in curriculum design. There was a difference in the way of reading curriculum materials that derived from different perspectives of curriculum reconstruction. The perspectives of curriculum reconstruction also affected the way of adapting curriculum materials. While the 'adding' was an important adaptation in curriculum design with active perspectives, the 'changing' was an important one with passive perspectives. In addition, the degrees of evaluating curriculum materials from the learners' views depended on their beliefs on teaching and learning. It was also connected to qualitative differences of adaptation in 'increasing student control over an activity' and 'increasing teacher control over an activity'. Educational implications of these findings are discussed.

The Development of Real-time Feedback Vibration Control System Using Wireless Sensor Networks (무선 센서 네트워크를 이용한 실시간 Feedback 진동제어 시스템 개발)

  • Heo, Gwang Hee;Kim, Chung Gil;Ahn, Ui Jong
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.16 no.3
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    • pp.60-66
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    • 2012
  • This paper aims to constitute a feedback vibration control system using wireless sensor networks and experiment it on a model structure to verify its effectiveness. For the purpose, we set up a feedback vibration control system composed of a wireless input/output(I/O) sensor node based on bluetooth, a home-made shear type MR damper, a shaker which generates a constant size of sine wave, and a simple beam model structure. The vibration control experiment was performed by shaking the 1/4 point of beam with a shaker. At the moment of shaking, we controled the vibration with MR damper which was placed vertically on the center of beam. Simultaneously, by acquiring acceleration response at the 2/4 point of beam, we evaluated the effectiveness of control capability. The control command was set to send a voltage signal to MR damper when the acceleration response, acquired from the wireless I/O sensor node placed at the center of beam, was more than a certain amount. Although the realtime feedback vibration control system constituted in this paper is effective only within a limited command system, it has been proven that the system was able to effectively decrease the vibration of structure by generating a control command aimed for realtime purpose. The system also showed a possibility to be used as a structural response control system adapting a variety of semi-active control algorithm.

Fuzzy Control of Smart Base Isolation System using Genetic Algorithm (유전자알고리즘을 이용한 스마트 면진시스템의 퍼지제어)

  • Kim, Hyun-Su;Roschke, P.N.
    • Journal of the Earthquake Engineering Society of Korea
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    • v.9 no.2 s.42
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    • pp.37-46
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    • 2005
  • To date, many viable smart base isolation systems have been proposed and investigated. In this study, a novel friction pendulum system (FPS) and an MR damper are employed as the isolator and supplemental damping device, respectively, of the smart base isolation system. A fuzzy logic controller (FLC) is used to modulate the MR damper because the FLC has an inherent robustness and ability to handle non linearities and uncertainties. A genetic algorithm (GA) is used for optimization of the FLC. The main purpose of employing a GA is to determine appropriate fuzzy control rules as well to adjust parameters of the membership functions. To this end, a GA with a local improvement mechanism is applied. This method is efficient in improving local portions of chromosomes. Neuro fuzzy models are used to represent dynamic behavior of the MR damper and FPS. Effectiveness of the proposed method for optimal design of the FLC is judged based on computed responses to several historical earthquakes. It has been shown that the proposed method can find optimal fuzzy rules and the GA optimized FLC outperforms not only a passive control strategy but also a human designed FLC and a conventional semi active control algorithm.

Optimal design of nonlinear damping system for seismically-excited adjacent structures using multi-objective genetic algorithm integrated with stochastic linearization method (추계학적 선형화 방법 및 다목적 유전자 알고리즘을 이용한 지진하중을 받는 인접 구조물에 대한 비선형 감쇠시스템의 최적 설계)

  • Ok, Seung-Yong;Song, Jun-Ho;Koh, Hyun-Moo;Park, Kwan-Soon
    • Journal of the Earthquake Engineering Society of Korea
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    • v.11 no.6
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    • pp.1-14
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    • 2007
  • Optimal design method of nonlinear damping system for seismic response control of adjacent structures is studied in this paper. The objective functions of the optimal design are defined by structural response and total amount of the dampers. In order to obtain a solution minimizing two mutually conflicting objective functions simultaneously, multi-objective optimization technique based on genetic algorithm is adopted. In addition, stochastic linearization method is embedded into the multi-objective framework to efficiently estimate the seismic responses of the adjacent structures interconnected by nonlinear hysteretic dampers without performing nonlinear time-history analyses. As a numerical example to demonstrate the effectiveness of the proposed technique, 20-story and 10-story buildings are considered and MR dampers of which hysteretic behaviors vary with the magnitude of the input voltage are considered as nonlinear hysteretic damper interconnecting two adjacent buildings. The proposed approach can provide the optimal number and capacities of the MR dampers, which turned out to be more economical than the uniform distribution system while maintaining similar control performance. The proposed damper system is verified to show more stable performance in terms of the pounding probability between two adjacent buildings. The applicability of the proposed method to the design problem for optimally placing semi-active control system is examined as well.

Computational Optimization of Bioanalytical Parameters for the Evaluation of the Toxicity of the Phytomarker 1,4 Napthoquinone and its Metabolite 1,2,4-trihydroxynapththalene

  • Gopal, Velmani;AL Rashid, Mohammad Harun;Majumder, Sayani;Maiti, Partha Pratim;Mandal, Subhash C
    • Journal of Pharmacopuncture
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    • v.18 no.2
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    • pp.7-18
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    • 2015
  • Objectives: Lawsone (1,4 naphthoquinone) is a non redox cycling compound that can be catalyzed by DT diaphorase (DTD) into 1,2,4-trihydroxynaphthalene (THN), which can generate reactive oxygen species by auto oxidation. The purpose of this study was to evaluate the toxicity of the phytomarker 1,4 naphthoquinone and its metabolite THN by using the molecular docking program AutoDock 4. Methods: The 3D structure of ligands such as hydrogen peroxide ($H_2O_2$), nitric oxide synthase (NOS), catalase (CAT), glutathione (GSH), glutathione reductase (GR), glucose 6-phosphate dehydrogenase (G6PDH) and nicotinamide adenine dinucleotide phosphate hydrogen (NADPH) were drawn using hyperchem drawing tools and minimizing the energy of all pdb files with the help of hyperchem by $MM^+$ followed by a semi-empirical (PM3) method. The docking process was studied with ligand molecules to identify suitable dockings at protein binding sites through annealing and genetic simulation algorithms. The program auto dock tools (ADT) was released as an extension suite to the python molecular viewer used to prepare proteins and ligands. Grids centered on active sites were obtained with spacings of $54{\times}55{\times}56$, and a grid spacing of 0.503 was calculated. Comparisons of Global and Local Search Methods in Drug Docking were adopted to determine parameters; a maximum number of 250,000 energy evaluations, a maximum number of generations of 27,000, and mutation and crossover rates of 0.02 and 0.8 were used. The number of docking runs was set to 10. Results: Lawsone and THN can be considered to efficiently bind with NOS, CAT, GSH, GR, G6PDH and NADPH, which has been confirmed through hydrogen bond affinity with the respective amino acids. Conclusion: Naphthoquinone derivatives of lawsone, which can be metabolized into THN by a catalyst DTD, were examined. Lawsone and THN were found to be identically potent molecules for their affinities for selected proteins.

Korean firms' Corporote Networks in Dalian City, China (중국 대련시(大連市) 한국기업의 네트워크 특성)

  • Lu, Bi Shun
    • Journal of the Korean association of regional geographers
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    • v.14 no.5
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    • pp.492-506
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    • 2008
  • This paper aims to explore the characteristics of regional network of Korean firms in Dalian City, China, which is focused on social, cultural and institutional characteristics. To achieve this goal, the paper attempts to analyze the supply of raw material and parts, sales and cooperative relations of the firms. Among Korean firms in Dalian City, the characteristic of non-local network can be seen in supply enterprise of raw material, parts and semi products. On the other hand, a tighter local network relationship can be seen in sales. Large companies appear stronger in non-local network than small businesses and small businesses are stronger in local network. In terms of cooperation among enterprises, many firms have networks of joint marketing, joint use of equipments, exchange of techniques and information with the supply enterprise. With the customer enterprise, there is a network in joint marketing and manpower training. Especially, most of the customer enterprises are Chinese ones, which have extensive networks in big cities, such as in Beijing, Shanghai, Guangzhou, Tianjin and Dalian. In local network, the Korean firms in Dalian cooperate in product development, finance and manpower training with local firms. And in non-local cooperation, Korean firms are active in tech support, information exchange and R&D.

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Inquiry-Based Science Instruction Perceived by Beginning Science Teachers in a Professional Learning Community (교사학습공동체 활동을 한 초임중등과학교사의 과학 탐구 수업에 대한 인식)

  • Kim, Yurim;Choi, Aeran
    • Journal of the Korean Chemical Society
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    • v.63 no.5
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    • pp.360-375
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    • 2019
  • The purpose of this study was to investigate beginning science teachers' perceptions of inquiry-based science instruction using open-ended questionnaire and semi-structured interview. Participants of this study voluntarily set up a goal of inquiry-based science instruction, planned inquiry-based science lessons, and shared and reflected their teaching experiences in their professional learning community for more than a year. Participant teachers recognized students' construction of core scientific concepts through performing scientific inquiry as a goal of science inquiry instruction. Participant teachers indicated that goals of science education such as 'learning scientific core concepts', 'improving students' interest of science', 'improving scientific thinking', and 'understanding the nature of science' can be achieved through students' active engagement in scientific inquiry. Participant teachers recognized not only the importance of teachers' role, but also what roles science teachers should play in order to enable students to perform scientific inquiry. Participant teachers emphasized teachers' roles such as 'identifying core concepts', 'reorganizing science curriculum', 'considering student ability', 'asking questions and providing feedbacks to students', 'explaining scientific concepts', and 'leading students' argumentation.'