• Title/Summary/Keyword: Press Policy

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Active feedback control for cable vibrations

  • Ubertini, Filippo
    • Smart Structures and Systems
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    • v.4 no.4
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    • pp.407-428
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    • 2008
  • The nonlinear mechanics of cable vibration is caught either by analytical or numerical models. Nevertheless, the choice of the most appropriate method, in consideration of the problem under study, is not straightforward. A feedback control policy might even enhance the complexity of the system. Thus, in order to design a suitable controller, different approaches are here adopted. Devices mounted transversely to the cable in the two directions, close to one of its ends, supply the feedback control action based on the observation of the response in a few points. The low order terms of the control law are, at first, analyzed in the framework of linear models. Explicit analytic solutions are derived for this purpose. The effectiveness of high order terms in the control law is then explored by means of a finite element model(FEM), which accounts for high order harmonics. A suitably dimensional analytical Galerkin model is finally derived, to investigate the effectiveness of the proposed control strategy, when applied to a physical model.

An integral based fuzzy approach to evaluate waste materials for concrete

  • Onat, Onur;Celik, Erkan
    • Smart Structures and Systems
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    • v.19 no.3
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    • pp.323-333
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    • 2017
  • Waste materials in concrete have been considered as one of the most important issues by the authorities, policy makers and researchers to maintain engineering serviceability in terms of economy, durability and sustainability. Therefore, evaluation and selection of waste materials with respect to multi criteria decision making (MCDM) for the construction industry has been gained importance for recovery and reuse. In this paper, Choquet integral based fuzzy approach is proposed for evaluating the most suitable waste materials with respect to compressive strength, tensile strength, flexural strength, compactness, toughness (resistivity for dynamic loads), water absorption and accessibility. On conclusion, waste tyre and silica fume were determined as the most suitable waste materials for concrete production. The obtained results are recommended to assist the authorities on configuring well designed strategies for construction industry with disposal materials.

Assessment of the potential for the design of marine renewable energy systems

  • Duthoit, Maxime;Falzarano, Jeffrey
    • Ocean Systems Engineering
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    • v.8 no.2
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    • pp.119-166
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    • 2018
  • The assessment of the potential for the design of marine renewable energy systems is reviewed and the current situation for marine renewable energy is promising. The most studied forms of marine renewable energy are ocean wind energy, ocean wave energy and tidal energy. Wind turbine generators include mostly horizontal axis type and vertical axis type. But also more exotic ideas such as a kite design. Wave energy devices consist of designs converting wave oscillations in electric power via a power take off equipment. Such equipment can take multiple forms to be more efficient. Nevertheless, the technology alone cannot be the only step towards marine renewable energy. Many other steps must be overcome: policy, environment, manpower as well as consumption habits. After reviewing the current conditions of marine renewable energy development, the authors analyzed the key factors for developing a strong marine renewable energy industry and pointed out the huge potential of marine renewable energy.

Advanced controller design for AUV based on adaptive dynamic programming

  • Chen, Tim;Khurram, Safiullahand;Zoungrana, Joelli;Pandey, Lallit;Chen, J.C.Y.
    • Advances in Computational Design
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    • v.5 no.3
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    • pp.233-260
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    • 2020
  • The main purpose to introduce model based controller in proposed control technique is to provide better and fast learning of the floating dynamics by means of fuzzy logic controller and also cancelling effect of nonlinear terms of the system. An iterative adaptive dynamic programming algorithm is proposed to deal with the optimal trajectory-tracking control problems for autonomous underwater vehicle (AUV). The optimal tracking control problem is converted into an optimal regulation problem by system transformation. Then the optimal regulation problem is solved by the policy iteration adaptive dynamic programming algorithm. Finally, simulation example is given to show the performance of the iterative adaptive dynamic programming algorithm.

Coupling shape-memory alloy and embedded informatics toward a metallic self-healing material

  • Faravelli, Lucia;Marzi, Alessandro
    • Smart Structures and Systems
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    • v.6 no.9
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    • pp.1041-1056
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    • 2010
  • This paper investigates the possibility of a strategy for an automatic full recover of a structural component undergoing loading-unloading (fatigue) cycles: full recover means here that no replacement is required at the end of the mission. The goal is to obtain a material capable of self healing earlier before the damage becomes irreversible. Attention is focused on metallic materials, and in particular on shape memory alloys, for which the recovering policy just relies on thermal treatments. The results of several fatigue tests are first reported to acquire a deep understanding of the physical process. Then, for cycles of constant amplitude, the self-healing objective is achieved by mounting, on the structural component of interest, a suitable microcontroller. Its input, from suitable sensors, covers the current stress and strain in the alloy. The microcontroller elaborates from the input the value of a decisional parameter and activates the thermal process when a threshold is overcome.

A study on nonlinear analysis and confinement effect of reinforced concrete filled steel tubular column

  • Xiamuxi, Alifujiang;Hasegawa, Akira;Yu, Jiang
    • Structural Engineering and Mechanics
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    • v.56 no.5
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    • pp.727-743
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    • 2015
  • According to former studies, the mechanical properties of reinforced concrete filled tubular steel (RCFT) columns differed greatly from that of concrete filled steel tubular (CFT) columns because of interaction of inserted reinforcement in RCFT. Employing an experiment-based verification policy, a general FE nonlinear analysis model was developed to analyze the mechanical behavior and failure mechanism of RCFT columns under uniaxial compression. The reasonable stress-strain relationships were suggested for confined concrete, reinforcements and steel tube in the model. The mechanism for shear failure of concrete core was found out in the numerical simulation, and a none-conventional method and equation for evaluating the confinement effect of RCFT were proposed.

Progress of renewable energy in India

  • Kar, Sanjay Kumar;Gopakumar, K.
    • Advances in Energy Research
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    • v.3 no.2
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    • pp.97-115
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    • 2015
  • Energy holds key to economic growth and prosperity of India. Currently, India has very high-energy import dependence, especially in the case of crude oil (80%) and natural gas (40%). Even coal import has been increasing over the years. Considering India's population growth, emphasis on manufacturing, production, and service industry, energy consumption is bound to increase. More fossil energy consumption means greater dependence on energy import leading to widening trade deficit and current account deficit. Therefore, exploitation of indigenous renewable energy production is necessary. The paper reviews the progress and growth of renewable energy production, distribution, and consumption in India. The paper highlights some of the enablers of renewable energy in India. The authors discuss the opportunities and challenges of increasing share of renewable energy to reduce energy import and address issues of energy security in India. The findings suggest that India is ready for a quantum leap in renewable production by 2022.

Optimal deep machine learning framework for vibration mitigation of seismically-excited uncertain building structures

  • Afshin Bahrami Rad;Javad Katebi;Saman Yaghmaei-Sabegh
    • Structural Engineering and Mechanics
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    • v.88 no.6
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    • pp.535-549
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    • 2023
  • Deep extreme learning machine (DELM) and multi-verse optimization algorithms (MVO) are hybridized for designing an optimal and adaptive control framework for uncertain buildings. In this approach, first, a robust model predictive control (RMPC) scheme is developed to handle the problem uncertainty. The optimality and adaptivity of the proposed controller are provided by the optimal determination of the tunning weights of the linear programming (LP) cost function for clustered external loads using the MVO. The final control policy is achieved by collecting the clustered data and training them by DELM. The efficiency of the introduced control scheme is demonstrated by the numerical simulation of a ten-story benchmark building subjected to earthquake excitations. The results represent the capability of the proposed framework compared to robust MPC (RMPC), conventional MPC (CMPC), and conventional DELM algorithms in structural motion control.

Characteristics of micro-plastics in stormwater sediment basin: Case study of J wetland

  • Jiyeol Im;Kyungik Gil
    • Membrane and Water Treatment
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    • v.14 no.4
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    • pp.147-153
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    • 2023
  • Urbanization has been causing such new pollutants as micro-plastic, thus the environmental impact of new pollutants on ecosystem is rapidly increasing. When it comes to micro-plastic, a representative artificial trace pollutant, its risk has been increased at a much faster rate, however the depth study associated with stormwater sediment and wetland was relatively rare. In this research, soil samples from storm water sediment were analyzed for distribution characteristics of micro-plastics in the J wetland (registered as Ramsar wetland, May 2021 and a representative environmental site in South Korea). Analyzed soil samples found approximately 201 ± 93 particle/kg (based on unit weight, Total micro plastic particles / Total Sample weight) micro-plastics in the samples. When considering the total quantitative numbers in stormwater sediment in the entire area of the J wetland, over 15,000 micro-plastics were estimated to be contaminating such area. In addition, in terms of qualitative numbers, micro-plastics were contaminating the J wetland with 94.7 % ratio of styrofoam type (43.9%) and polyethylene type (50.8%). These research results can be used as base data sets for controlling micro-plastics in the J wetland.

Study on the creative development of China Cartoon & Animation - Focusing on changes in a production environment with supporting the policy of the State Administration of Press, Publication, Radio, Film and Television of China - (중국 만화 애니메이션 창작과 발전 방향에 관한 연구 -국가광전총국(國家廣電總局) 지원정책에 따른 제작환경 변화를 중심으로-)

  • Xie, Shu-Fu;Kim, Jong-Du
    • Cartoon and Animation Studies
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    • s.35
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    • pp.209-226
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    • 2014
  • Chinese cartoon industry lately was able to see a rapid development which changed cartoon creative personnel associated with increased production technology development, new technologies, government support policy and a variety of environments. It was likely to have high expectations for changes in the policy environment of the country supported the comic creators and authors to develop its own comic industry. The State Administration of Press, Publication, Radio, Film and Television of China promoted the production for the development of Chinese animation with "domestic little video about the development of the animation industry's opinion", and "documents Documents". Animation industrial base and animation education was established in institutions such as the organization one after another. In the meantime, the spread of Japanese comics picture on the creative activation admitted but their comic creation and activation was slump. It would produce that the creation of its traditional culture based activation strategy to built comics. Since 2004, It was well represented for the creators of the cartoon creation of the tradition and uniqueness of Chinese history. In the prior to 2004, comics and strategies was to be differentiated. Today, China is an important source of comic marked the fact that the tradition was recognized and it was further developed with combining creativity of the past and the present production system. Comic creators comic story of traditional culture were excavated in order to have a sense of awareness and modern. The difference between China Cartoon and comics in other Asian countries is true that cartoon story came out naturally in a traditional culture. In this study, It would lead in the future to allow directional presented for the digital cartoon making development policy awareness through the comic creation and production of new media content industry enabled to China. Now, in the new media industry for the development of China's neighboring countries coped with climate change for the active exchange of information. It poured out ceaseless technical development and a range of policies to support business expansion. New China Cartoon was leaped to re-fit the industry.