• Structural Engineering and Mechanics
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• v.46 no.5
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• pp.673-693
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• 2013

This paper presents a systematic design and training procedure for the feed-forward back-propagation neural network (NN) modeling of both forward and inverse behavior of a rotary magnetorheological (MR) damper based on experimental data. For the forward damper model, with damper force as output, an optimization procedure demonstrates accurate training of the NN architecture with only current and velocity as input states. For the inverse damper model, with current as output, the absolute value of velocity and force are used as input states to avoid negative current spikes when tracking a desired damper force. The forward and inverse damper models are trained and validated experimentally, combining a limited number of harmonic displacement records, and constant and half-sinusoidal current records. In general the validation shows accurate results for both forward and inverse damper models, where the observed modeling errors for the inverse model can be related to knocking effects in the measured force due to the bearing plays between hydraulic piston and MR damper rod. Finally, the validated models are used to emulate pure viscous damping. Comparison of numerical and experimental results demonstrates good agreement in the post-yield region of the MR damper, while the main error of the inverse NN occurs in the pre-yield region where the inverse NN overestimates the current to track the desired viscous force.

• Proceedings of the IEEK Conference
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• summer
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• pp.421-426
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• 2004

Analyzing adaptive possibilities of agents in multi-agents system, we have discovered new aspects of ambient intelligence in distributed modular systems using intelligent building blocks (I-BLOCKS) [1]. This paper describes early scientific researches related to technical design, applicable experiments and evaluation of adaptive processing and information interaction among I-BLOCKS allowing users to easily develop ambient intelligence applications. The processing technology presented in this paper is embedded inside each DUPLO1 brick by microprocessor as well as selected sensors and actuators in addition. Behaviors of an I-BLOCKS modular structure are defined by the internal processing functionality of each I-Blocks in such structure and communication capacities between I-BLOCKS. Users of the I-BLOCKS system can do 'programming by building' and thereby create specific functionalities of a modular structure of intelligent artefacts without the need to learn and use traditional programming language. From investigating different effects of modem artificial intelligence, I-BLOCKS we have developed might possibly contain potential possibilities for developing applications in ambient intelligence (AmI) environments. To illustrate these possibilities, the paper presents a range of different experimental scenarios in which I-BLOCKS have been used to set-up reconfigurable modular systems. The paper also reports briefly about earlier experiments of I-BLOCKS in different research fields, allowing users to construct AmI applications by a just defined concept of modular artefacts [3].

• Journal of Electrical Engineering and Technology
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• v.11 no.5
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• pp.1165-1178
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• 2016

• Journal of the Korea Furniture Society
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• v.12 no.1
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• pp.81-89
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• 2001

Scandinavian countries have hold tradition shared historically and culturally in common, brought the weighty traditional thoughts enabled to develop their unique culture. Since 1940s, Scandinavian design could pervade with affectionate forms and practical effectiveness with worldwide popularity. It was brought by creation of new and useful forms for the convenience in life, functionalism but not bounded by fashion of it. This study tried into the meaning of their history of modern furnishings design based on the development background of furnishings design, its trends, designers and their work focused around Sweden, Finland, and Denmark. Scandinavian furnishings is a functional furnishings reconciled to natural material and human life exactly correspond to the taste of the generation unrestricted from the tradition of contemporary and compact design preference or classic favored preference. The practicality and exquisite techniques of Scandinavian furnishings lies within the realm of possibility for studiously love of the world.

• The Bulletin of The Korean Astronomical Society
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• v.37 no.2
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• pp.207.1-207.1
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• 2012

One of the key aspects of the upcoming Ultra-Fast Observatory (UFFO) Pathfinder for Gamma-Ray Bursts(GRBs) identification will be the UFFO Burst Alert & Trigger Telescope(UBAT), based on a novel space telescope technique. The UBAT consists of coded mask, hopper, and detector module(DM). The UBAT DM consists of YSO crystal arrays, multi-anode photo mulipliers, and readout electronics. We will present the design and construction of the UBAT DM, and the response of the UBAT DM to X-ray sources.

• Smart Structures and Systems
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• v.18 no.1
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• pp.75-92
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• 2016

The design of a semi-active (SA) control system addressed to mitigate wind induced structural demand to high wind turbine towers is discussed herein. Actually, the remarkable growth in height of wind turbines in the last decades, for a higher production of electricity, makes this issue pressing than ever. The main objective is limiting bending moment demand by relaxing the base restraint, without increasing the top displacement, so reducing the incidence of harmful "p-delta" effects. A variable restraint at the base, able to modify in real time its mechanical properties according to the instantaneous response of the tower, is proposed. It is made of a smooth hinge with additional elastic stiffness and variable damping respectively given by springs and SA magnetorheological (MR) dampers installed in parallel. The idea has been physically realized at the Denmark Technical University where a 1/20 scale model of a real, one hundred meters tall wind turbine has been assumed as case study for shaking table tests. A special control algorithm has been purposely designed to drive MR dampers. Starting from the results of preliminary laboratory tests, a finite element model of such structure has been calibrated so as to develop several numerical simulations addressed to calibrate the controller, i.e., to achieve as much as possible different, even conflicting, structural goals. The results are definitely encouraging, since the best configuration of the controller leaded to about 80% of reduction of base stress, as well as to about 30% of reduction of top displacement in respect to the fixed base case.

• Structural Engineering and Mechanics
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• v.52 no.2
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• pp.261-274
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• 2014

An accurate finite element (FE) model of a structure is essential for predicting reliably its dynamic characteristics. Such a model is used to predict the effects of structural modifications for dynamic design of the structure. These modifications may be imposed by design alterations for operating reasons. Most of the model updating techniques neglect damping and so these updated models can't be used for accurate prediction of vibration amplitudes. This paper deals with the basic formulation of damped finite element model updating method and its use for structural dynamic modifications. In this damped damped finite element model updating method, damping matrices are updated along with mass and stiffness matrices. The damping matrices are updated by updating the damping coefficients. A case involving actual measured data for the case of F-shaped test structure, which resembles the skeleton of a drilling machine is used to evaluate the effectiveness of damped FE model updating method for accurate prediction of the vibration levels and thus its use for structural dynamic modifications. It can be concluded from the study that damped updated FE model updating can be used for structural dynamic modifications with confidence.

• Proceedings of the KIEE Conference
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• 2004.11c
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• pp.313-315
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• 2004

Urodynamic study system is widely used for neurogenic bladder patients in various clinical setting. Generally they include 2 pressure sensors from bladder and rectum, and 1 EMG sensor. The rectal pressure catheter is often the source of data error because of gas passage and the fall out of the catheter from anus, and source of discomfort in ambulatory urodynamic system. This study is to design and calibrate the ambulatory digital urodynamic study system that can discard the rectal pressure catheter, which can make patients more comfortable and doctors can get more physiologic data. As a first step, we compared our new system with Dantec $Duet^{(r)}$ urodynamic system (Dantec, Denmark) and wanted to see the possibility of our new system.

• Proceedings of the IEEK Conference
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• summer
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• pp.410-415
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• 2004

Employing knowledge of adaptive possibilities of agents in multi-agents system, we have explored new aspects of distributed modular systems for building ubiquitous heterogeneous robotic systems using intelligent building blocks (I-BLOCKS) [1] as reconfigurable modules. This paper describes early technological approaches related to technical design, experimental developments and evaluation of adaptive processing and information interaction among I-BLOCKS allowing users to easily develop modular robotic systems. The processing technology presented in this paper is embedded inside each $DUPLO^1$ brick by microprocessor as well as selected sensors and actuators in addition. Behaviors of an I-BLOCKS modular structure are defined by the internal processing functionality of each I-Block in such structure and communication capacities between I-BLOCKS. Users of the I-BLOCKS system can easily do 'programming by building' and thereby create specific functionalities of a modular robotic structure of intelligent artefacts without the need to learn and use traditional programming language. From investigating different effects of modern artificial intelligence, I-BLOCKS we have developed might possibly contain potential possibilities for developing modular robotic system with different types of morphology, functionality and behavior. To assess these potential I-BLOCKS possibilities, the paper presents a limited range of different experimental scenarios in which I-BLOCKS have been used to set-up reconfigurable modular robots. The paper also reports briefly about earlier experiments of I-BLOCKS created on users' natural inspiration by a just defined concept of modular artefacts.

• East Asian Journal of Business Economics (EAJBE)
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• v.6 no.1
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• pp.1-31
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• 2018

Purpose - This study is to analyze indicators characterizing the monetary turnover and its determining factors. Also this paper looked at the evolution of monetary aggregates of the Russian Federation, Australian, Sweden, Denmark, countries of CIS at the present stage of development and in the historical context. Research design, data, and methodology - The scale of research on Russia: to be analyzed the amount of data from the 2011 by 2016. In the historical context of the estimated data in the 1900-2011. On Belarus - the 2007-2017, on Tajikistan - the 2000 - 2017, on Kazakhstan - the 2000-2017, on Kyrgyzstan - the 2000-2017, on Australian - the 1959-2017, on Sweden - the 2009-2017, on Denmark - the 1999-2017. Results - Hypothesis 1. In Russian Federation the monetary stock has the steady tendency to growth. The dynamics of money supply in Russia is largely determined by historical events. Hypothesis 2. The dynamics of money supply the leading countries-partners has the tendency to grow. The monetary amount of countries-partners are analyzed is largely determined by external debt, GDP, the exports, the imports, the international reserves. Conclusions - The dynamics of monetary stock of Russia is determined by the historical events in many respects. The Russian Federation maintains a steady and the liquid economic position in the case of considerable amount of monetary stock and the high degree of its surplus. In most of the countries studied, the monetary supply has a significant volume exceeding the needs of the economy. If the distribution of monetary mass is adequate and there is a vertical of financial control, this will not have a negative impact on the country's economic stability and the development.