• Structural Engineering and Mechanics
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• v.13 no.2
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• pp.135-154
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• 2002

This paper presents the convected material frame approach to study the nonlinear behavior of inelastic frame structures. The convected material frame approach is a modification of the co-rotational approximation by incorporating an adaptive convected material frame in the basic definition of the displacement vector and strain tensor. In the formulation, each discrete element is associated with a local coordinate system that rotates and translates with the element. For each load increment, the corresponding strain-displacement and nodal force-stress relationships are defined in the updated local coordinates, and based on the updated element geometry. The rigid body motion and deformation displacements are decoupled for each increment. This modified approach incorporates the geometrical nonlinearities through the continuous updating of the material frame geometry. A generalized nonlinear function is used to derive the inelastic constitutive relation and the kinematic hardening is considered. The equation of motion is integrated by an explicit procedure and it involves only vector assemblage and vector storage in the analysis by assuming a lumped mass matrix of diagonal form. Several numerical examples are demonstrated in close agreement with the solutions obtained by the ANSYS code. Numerical studies show that the proposed approach is capable of investigating large deflection of inelastic planar structures and providing an excellent numerical performance.

• Coupled systems mechanics
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• v.3 no.4
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• pp.329-344
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• 2014

In this work, quantum molecular dynamics simulations (QMD) are preformed to study the hydrogen molecules in three types of carbon nanostructures, $C_{60}$ fullerene, (5,5) and (9,0) carbon nanotubes and graphene layers. Interactions between hydrogen and the nanostructures is of importance to understand hydrogen storage for the development of hydrogen economy. The QMD method overcomes the difficulties with empirical interatomic potentials to model the interaction among hydrogen and carbon atoms in the confined geometry. In QMD, the interatomic forces are calculated by solving the Schrodinger's equation with the density functional theory (DFT) formulation, and the positions of the atomic nucleus are calculated with the Newton's second law in accordance with the Born-Oppenheimer approximation. It is found that the number of hydrogen atoms that is less than 58 can be stored in the $C_{60}$ fullerene. With larger carbon fullerenes, more hydrogen may be stored. For hydrogen molecules passing though the fullerene, a particular orientation is required to obtain least energy barrier. For carbon nanotubes and graphene, adsorption may adhere hydrogen atoms to carbon atoms. In addition, hydrogen molecules can also be stored inside the nanotubes or between the adjacent layers in graphite, multi-layer graphene.

• Neurospine
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• v.15 no.4
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• pp.285-295
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• 2018

As spine surgery flourished in Taiwan and neurosurgeons became more involved in spine surgery towards the end of the 20th century, the Taiwan Neurosurgical Spine Society (TNSS), earlier named the Taiwan Neurospinal Society, was established on March 11, 2001. As its main founder, Dr. Chun-I Huang was elected as the first president of the TNSS. The goals of the TNSS were to promote research, to hold academic seminars, to participate in international conferences, and to exchange clinical experiences. The mission of the TNSS was successful, and the profession of spine surgery in Taiwan advanced during the first decade of the 21st century, culminating in the TNSS joining ASIA SPINE in 2010. Since its establishment, the TNSS has always been supportive of collaboration and communication with the Korean Spinal Neurosurgery Society and the Neurospinal Society of Japan. Through periodical meetings, supported by the TNSS, surgeons worldwide have enjoyed a platform of sharing and mutual learning. To further promote academic research, the TNSS has officially supported the journal Neurospine since 2018. With extensive efforts from local and international surgeons, the TNSS will continue to adhere to its mission and to advance the profession of spine surgery.

• Proceedings of the Korean Magnestics Society Conference
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• 2007.05a
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• pp.215.2-215.2
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• 2007

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2010.11a
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• pp.647-648
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• 2010

• The Journal of Korean Philosophical History
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• no.50
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• pp.9-36
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• 2016

This thesis aims to suggest probability of modern confrontation of Yulgok YiYi's thought. For this, find out the meaning of Li-Qi-Zhi-Miao(理氣之妙) and through the Qi-Fa-Li-Cheng-Yi-Tu(氣發理乘一途), and Li-Tong-Qi-Ju-Shou(理通 氣局說), Yin-Xim-Do-Xim-Shou(人心道心說), he creatively reveal the relation of Xin(心) Xing(性) Qing(情) Yi(意) continually. On one side he suggested the way of ideal man, on the other side he was showed adaptablity to the real world. So I think Yulgok had placed emphasis on the Zhongyong(中庸) and Yijing(周易), so he point out the meaning of ShiZhong (時中). Then he had high ideals practical Zhi-Zhonghe((致中和). So This paper is to find out his foundation of epistemology, and then to know It's modern meaning of methodology of moral Education's Implication on the relation of Xin(心) Xing(性) Qing(情) Yi(意). So We ca find out Ji(機) is very important the transition of Qi-Zhe(氣質).

• International Journal of Naval Architecture and Ocean Engineering
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• v.8 no.1
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• pp.38-52
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• 2016

This paper describes the nonlinear dynamic motion behavior of a ship equipped with a portable dynamic positioning (DP) control system, under external forces. The waves, current, wind, and drifting forces were considered in the calculations. A self-tuning controller based on a neuro-fuzzy algorithm was used to control the rotation speed of the outboard thrusters for the optimal adjustment of the ship position and heading and for path tracking. Time-domain simulations for ship motion with six degrees of freedom with the DP system were performed using the fourth-order RungeeKutta method. The results showed that the path and heading deviations were within acceptable ranges for the control method used. The portable DP system is a practical alternative for ships lacking professional DP facilities.

• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.540-542
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• 2008

By ETFOS software simulation to swiftly find out the shortcomings of the device structure and conserve the wastage of time cost in experiments, including the instruments deviations or human errors. Thereby we can calibrate the correct organic layer thickness by comparing the EL spectra with different NPB thicknesses.

• Journal of international Conference on Electrical Machines and Systems
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• v.1 no.1
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• pp.61-66
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• 2012

Linear motors has been developed for factory automation, transportation applications, among other applications. As the trend toward compact sizes in micro electronic products progresses, the required motor drives in these applications need to be downsized with increased power densities. It appears that the winding of miniature linear motors is the most awkward part to be scaled down from conventional motor designs when miniaturizing. This paper presents an alternative design for slotless linear motors. A novel flexible printed circuit winding has been applied to obtain a simplified but qualified result. Having explained the prototyping and inspection, a discussion is given to examine the achievement of this study.

• Journal of Communications and Networks
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• v.8 no.3
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• pp.351-359
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• 2006

In this article, we present a new slow-start variant, which improves the throughput of transmission control protocol (TCP) Vegas. We call this new mechanism Gallop-Vegas because it quickly ramps up to the available bandwidth and reduces the burstiness during the slow-start phase. TCP is known to send bursts of packets during its slow-start phase due to the fast window increase and the ACK-clock based transmission. This phenomenon causes TCP Vegas to change from slow-start phase to congestion-avoidance phase too early in the large bandwidth-delay product (BDP) links. Therefore, in Gallop-Vegas, we increase the congestion window size with a rate between exponential growth and linear growth during slow-start phase. Our analysis, simulation results, and measurements on the Internet show that Gallop-Vegas significantly improves the performance of a connection, especially during the slow-start phase. Furthermore, it is implementation feasible because only sending part needs to be modified.