• Proceedings of the Korean Society For Composite Materials Conference
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• 2003.10a
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• pp.171-174
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• 2003

The Special orthotropic plate theory is used for analysis of panels made of steel girders and cross-beams, and made of reinforced concrete. The cross-sections of girders and cross-beams are WF types. The result is compared with that of the beam theory. According to the numerical examination given in this paper, the result by the plate theory is 2.43 times stiffer than that of beam theory, The result for the concrete slab in given for the practicing engineers.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.8 no.11
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• pp.3674-3710
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• 2014

In this tutorial, we integrate the concept of cognitive radio technology into game theory and supermarket game theory to address the problem of resource allocation in multiuser multicarrier cognitive radio networks. In addition, multiuser multicarrier transmission technique is chosen as a candidate to study the resource allocation problem via game and supermarket game theory. This tutorial also includes various definitions, scenarios and examples related to (i) game theory (including both non-cooperative and cooperative games), (ii) supermarket game theory (including pricing, auction theory and oligopoly markets), and (iii) resource allocation in multicarrier techniques. Thus, interested readers can better understand the main tools that allow them to model the resource allocation problem in multicarrier networks via game and supermarket game theory. In this tutorial article, we first review the most fundamental concepts and architectures of CRNs and subsequently introduce the concepts of game theory, supermarket game theory and common solution to game models such as the Nash equilibrium and the Nash bargaining solution. Finally, a list of related studies is highlighted and compared in this tutorial.

• Journal of The Korean Association For Science Education
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• v.24 no.4
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• pp.758-773
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• 2004

This paper advances the thesis that the barrier separating curriculum theorists and practitioners is more than a difference in experiential and methodological orientation and is in part a product of a lack of appreciation of the complexities involved in curriculum development and dissemination. Discussed here is the possible use of engineering theory to facilitate meaningful communication and understanding about products and development. This work is an extension of the observation that curriculum development and dissemination can be characterized as an engineering process and shows how engineering theory provides connectivity between the multiple embedded domains of theory and of practice. To illustrate the thesis this paper offers an analysis of the Developmental Approaches in Science, Health, and Technology (DASH) program that has employed engineering theory in curriculum construction and dissemination. In this study, the role and place of engineering theory as applied to the DASH program is discussed to show how the components were designed and assembled into a fully functional curriculum and dissemination system. Engineering theory is presented as an interfacing organizer with the potential to facilitate meaningful communication between theorists and practitioners.

• Advances in concrete construction
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• v.1 no.3
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• pp.239-252
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• 2013

Mortar microstructure is considered as a three-phase composite material, which is cement paste, fine aggregate and interfacial transition zone. Interfacial transition zone is the weakest link between the cement paste and fine aggregate, so it has a significant role to determine the properties of cementitious composites. In this study, specimens (w/c = 0.35, 0.45, 0.55) with various volume fractions of fine aggregate ($V_f$ = 0, 0.1, 0.2, 0.3 and 0.4) were cast and tested. To predict the equivalent migration coefficient ($M_e$) and migration coefficient of interfacial transition zone ($M_{itz}$), double-inclusion method and Mori-Tanaka theory were used to estimate. There are two stages to estimate and calculate the thickness of interfacial transition zone (h) and migration coefficient of interfacial transition zone ($M_{itz}$). The first stage, the data of experimental chloride ion migration coefficient ($M_s$) was used to calculate the equivalent migration coefficient of fine aggregate with interfacial transition zone ($M_e$) by Mori-Tanaka theory. The second stage, the thickness of interfacial transition zone (h) and migration coefficient of interfacial transition zone ($M_{itz}$) was calculated by Hori and Nemat-Nasser's double inclusion model. Between the theoretical and experimental data a comparison was conducted to investigate the behavior of interfacial transition zone in mortar and the effect of interfacial transition zone on the chloride migration coefficient, the results indicated that the numerical simulations is derived to the $M_{itz}/M_m$ ratio is 2.11~8.28. Additionally, thickness of interfacial transition zone is predicted from $10{\mu}m$, 60 to $80{\mu}m$, 70 to $100{\mu}m$ and 90 to $130{\mu}m$ for SM30, M35, M45 and M55, respectively.

• International Journal of Concrete Structures and Materials
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• v.10 no.2
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• pp.143-147
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• 2016

In recent years, some modifications were introduced in the stress-strain relationship of the steel in order to develop a more efficient shear model for reinforced concrete members. The last contribution in this sense corresponding to the Refined Compression Field Theory (RCFT, 2009); this theory proposed a steel constitutive model that has account the tension stiffening area prescribed by technical codes, what simplifies all the design process. However, under certain design conditions supported by such codes, the RCFT model does not provide a real (non-complex) solution for the steel yield strain when the prescribed tension stiffening area is considered; then the load-strain response cannot be computed. In this technical note, the tension stiffening area is fixed in order to guarantee the application of the embedded steel constitutive model for all the standard design range.

• Advances in aircraft and spacecraft science
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• v.5 no.6
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• pp.615-632
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• 2018

Mechanical buckling of a rectangular functionally graded plate is obtained in the current paper using a refined higher-order shear and normal deformation theory. The impact of transverse normal strain is considered. The material properties are microscopically inhomogeneous and vary continuously based on a power law form in spatial direction. Navier's procedure is applied to examine the mechanical buckling behavior of a simply supported FG plate. The mechanical critical buckling subjected to uniaxial and biaxial compression loads are determined. The numerical investigation are compared with the numerical results in the literature. The influences of geometric parameters, power law index and different loading conditions on the critical buckling are studied.

• Research in Mathematical Education
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• v.13 no.4
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• pp.349-377
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• 2009

In this work we present a study undertaken with in-service mathematics teachers of primary and secondary school where we describe and analyze the didactical competences needed to implement an innovative design in geometry applying Van Hiele's models. The relationship between such competences and an ideal teacher profile is also studied. Teachers' epistemology is established in terms of didactical competences and we can see that this epistemology is an element that helps us understand the difficulties that teachers face in practice when implementing an innovative curriculum, in this case, geometry based on the Van Hiele theory.

• Steel and Composite Structures
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• v.26 no.4
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• pp.421-437
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• 2018

Free vibration analysis of a three-layered microbeam including an elastic micro-core and two piezo-magnetic face-sheets resting on Pasternak's foundation are studied in this paper. Strain gradient theory is used for size-dependent modeling of microbeam. In addition, three-unknown shear and normal deformations theory is employed for description of displacement field. Hamilton's principle is used for derivation of the governing equations of motion in electro-magneto-mechanical loads. Three micro-length-scale parameters based on strain gradient theory are employed for prediction of vibrational characteristics of structure in micro-scale. The results show that increase of three micro-length-scale parameters leads to significant increase of three natural frequencies especially for increase of second micro-length-scale parameter. This result is according to this fact that stiffness of a micro-scale structure is increased with increase of micro-length-scale parameters.

• Ocean Systems Engineering
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• v.2 no.4
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• pp.297-314
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• 2012

Power-take-off through inner dynamic system inside a floating buoy is suggested. The power take-off system is characterized by mass, stiffness, and damping and generates power through the relative heave motion between the buoy and inner mass (magnet or amateur). A systematic hydrodynamic theory is developed for the suggested WEC and the developed theory is illustrated by a case study. A vertical truncated cylinder is selected as a buoy and the optimal condition of the inner dynamic system for maximum PTO (power take off) through double resonance for the given wave condition is systematically investigated. Through the case study, it is seen that the maximum power can actually be obtained at the optimal spring and damper condition, as predicted by the developed WEC theory. However, the band-width of high performance region is not necessarily the greatest at the optimal (maximum-power-take-off) condition, so it has to be taken into consideration in the actual design of the WEC.

• Korean Journal of Acupuncture
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• v.25 no.2
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• pp.1-32
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• 2008

Objectives : This study was performed to understand the interrelation between 'Foot three yang meridian-muscle' and 'muscular system'. Methods : We have researched some of the literatures on Meridian-muscle theory, anatomical muscular system, myofascial pain syndrome and anatomy trains. And especially we have compared myofascial pain syndrome to anatomy trains and researched what kind of relationship is exist between them. Results : It is considered that Foot taeyang meridian-muscle includes Abductor digiti minimi m., Gastrocnemius m., Biceps femoris m., Longissimus m., Omohyoid m., Occipital m., Frontal m., Orbicularis oculi m., Trapezius m., Sternocleidomastoid m., Sternohyoid m., Zygomaticus m. Foot soyang meridian-muscle includes Dorsal interosseus m., Tendon of extensor digitorum longus m., Extensor digitorum longus m., Iliotibial band, Vastus lateralis m., Piriformis m., Tensor fasciae latae m., Internal abdominal oblique m., External abdominal oblique m,, Internal intercostal m., External intercostal m., Pectoralis major m., Sternocleidomastoid m., Posterior auricular m., Temporal m., Masseter m., Orbicularis oculi m. Foot yangmyung meridian-muscle includes Extensor digitorum longus m., Vastus lateralis m., Iliotibial band, Iliopsoas m., Anterior tibial m., Rectus femoris m., Sartorius m., Rectus abdominis m., Pectoralis major m., Internal intercostal m., External intercostal m., Sternocleidomastoid m., Masseter m., Levator labii superioris m., Zygomatic major m., Zygomatic minor m., Orbicularis oculi m., Buccinator m. and the symptoms of Foot three yang meridian-muscle are similar to the myofascial pain syndrome. Superficial back line in anatomy trains is similar to the pathway of Foot taeyang meridian-muscle. Lateral Line in anatomy trains is similar to the pathway of Foot soyang meridian-muscle. Superficial Front Arm Line in anatomy trains is similar to the pathway of Foot yangmyung meridian-muscle. Conclusions : There is some difference between myofascial pain syndrome and meridian-muscle theory in that the former explains each muscle individually, while the latter classifies muscular system in the view of integrated organism. More studies are needed in anatomy and physiology to support the integration of muscular system of Foot three yang meridian-muscle in aspect of anatomy trains.