• Journal of Institute of Control, Robotics and Systems
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• v.18 no.6
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• pp.555-561
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• 2012

This paper describes the design of a fuzzy adaptive sliding mode controller for tracking control of robotic manipulators. The proposed controller incorporates a modified traditional sliding mode controller to drive the system state to a sliding surface and then keep the system state on this surface, and a fuzzy logic controller to accelerate the reaching phase. The stability of the control system is ensured by using Lyapunov theory. To verify the effectiveness of the proposed controller, computer simulation is conducted for a five-bar planar robotic manipulator. The simulation results show that the proposed controller can improve the reaching time and eliminate chattering of the control system at the same time.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.29 no.11 s.242
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• pp.1248-1256
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• 2005

This study was undertaken to investigate the flow characteristics of emulsified fuel with the ultrasonic energy-adding system by using the chaotic method. Efffcts of water contents within emulsified fuel, flow rate and tube length with 5m in diameter from an emulsified chamber has been discussed on the strange attractor and power spectral density function. Five probe sensors were set up from 0.5 to 2.5m by length in 0.5m increments in the tube. In particular, the chaotic features of this system have been practically characterized in terms of chaotic statistics such as the power spectral density function and phase space portraits by resorting to the somewhat noble deterministic chaos theory. In the tube, the dominant frequency increased with increasing water contents and flow rate, but decreased a little with an increase in the length from the emulsified chamber.

• Bulletin of the Korean Chemical Society
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• v.33 no.11
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• pp.3797-3804
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• 2012

We present calculations for valine (Val) - $(H_2O)_n$ (n = 0-5) to examine the effects of microsolvating water on the relative stability of the zwitterionic vs. canonical forms of Val. We calculate the structures, energies and Gibbs free energies of the conformers at B3LYP/6-311++G(d,p), wB97XD/6-311++G(d,p) and MP2/aug-cc-pvdz level of theory. We find that five water molecules are needed to stabilize the zwitterionic form of Val. By calculating the barriers of the canonical ${\leftrightarrow}$ zwitterionic pathways of Val - $(H_2O)_5$ conformers, we suggest that both forms of Val - $(H_2O)_5$ may be observed in low temperature gas phase.

• Journal of Physiology & Pathology in Korean Medicine
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• v.33 no.5
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• pp.261-266
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• 2019

In order to cope with various issues about access to public health system of Korean medicine and reformation of college curriculum and argument of pseudoscience on Korean medicine etc., a new definition of Korean medicine was devised. Two ways of approach were tried through analysis of precedent cases of definition on traditional medicine firstly and analysis on concept and logic of Korean medicine secondly. As a result, Korean medicine can be defined as a science of theories and application techniques for maintaining health and diagnosing, treating and preventing conditions、causes、prognosis of diseases or damages based on the correlative and complicated understanding about the structure and function of mind and body out of human lives under the environment and society. This definition can be used as a basis to derive legal rights or scope in area of research and education policies and social institutions of the Korean medicine and to confront scientification criticism hereafter.

• Educational Technology International
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• v.14 no.1
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• pp.27-40
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• 2013

Design-Based Research (DBR) focuses on developing key principles of interventions to advance both theory and practicalities of dissemination (Brown, 1992), yet its methodological details have not been quite established. Thus, the purpose of this paper is to address the pragmatics of DBR by sharing the researcher's reflections on conducting a longitudinal DBR project for five years. In an attempt to advance college teaching practices as well as theories related to student plagiarism, the project focused on refining "humble" theories on how and why college students engage in plagiarism to design classroom interventions for promoting academic integrity. Similar to the Integrative Learning Design (ILD) framework proposed by Bannan-Ritland (2003), but conducted in a much simpler and less formal format, this study followed DBR cycles from initial conceptualization to design and enact instructional interventions in authentic contexts while collecting both quantitative and qualitative data from each phase. Finally, the paper addresses some challenges encountered throughout the DBR project as well as the lessons learned from this experience. Like many previous DBR studies whose practical relevance is limited to local context, the findings from this study may not be easily generalized for other contexts.

• Bulletin of the Korean Chemical Society
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• v.24 no.5
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• pp.583-592
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• 2003

The gas phase identity nucleophilic substitution reactions of halide anions (X = F, Cl, Br) with cyclopentadienyl halides (1) are investigated at the B3LYP/6-311+G**, MP2/6-311+G** and G2(+)MP2 levels involving five reaction pathways: σ-attack $S_N2$, β-$S_N$2'-syn, β-$S_N$2'-anti, γ-$S_N$2'-syn and γ-$S_N$2'-anti paths. In addition, the halide exchange reactions at the saturated analogue, cyclopentyl halides (2), and the monohapto circumambulatory halide rearrangements in 1 are also studied at the same three levels of theory. In the σ-attack $S_N2$ transition state for 1 weak positive charge develops in the ring with X = F while negative charge develops with X = Cl and Br leading to a higher energy barrier with X = F but to lower energy barriers with X = Cl and Br than for the corresponding reactions of 2. The π-attack β-$S_N$2' transition states are stabilized by the strong $n_C-{\pi}^{*}_{C=C}$ charge transfer interactions, whereas the π-attack γ-$S_N$2' transition states are stabilized by the strong $n_C-{\sigma}^{*}_{C-X}$ interactions. For all types of reaction paths, the energy barriers are lower with X = F than Cl and Br due to the greater bond energy gain in the partial C-X bond formation with X = F. The β-$S_N$2' paths are favored over the γ-$S_N$2' paths only with X = F and the reverse holds with X = Cl and Br. The σ-attack $S_N2$ reaction provides the lowest energy barrier with X = Cl and Br, but that with X = F is the highest energy barrier path. Activation energies for the circumambulatory rearrangement processes are much higher (by more than 18 kcal $mol^{-1}$) than those for the corresponding $S_N2$ reaction path. Overall the gas-phase halide exchanges are predicted to proceed by the σ-attack $S_N2$ path with X = Cl and Br but by the β-$S_N$2'-anti path with X = F. The barriers to the gas-phase halide exchanges increase in the order X = F < Br < Cl, which is the same as that found for the gas-phase identity methyl transfer reactions.

• The Journal of Internal Korean Medicine
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• v.32 no.1
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• pp.87-99
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• 2011

In the 18th century, Xu Lingtai (徐靈胎) and Yoshimasu Todo (吉益東洞) were medical revolutionaries. They emphasized researches about synthesis of formulae, efficacy of medication and observation and then classification of clinical phenomena, so they assumed a modern scientific character. But, there were clear differences between their academic thoughts. In this paper, we examine the causes of difference in three fields, i.e. traditional culture, viewpoints of talented people and academic personality. The first, difference was due to traditional culture. Chinese medicine has a long history and heavy traditional culture. Yin-Yang (陰陽) theory, Five Phase(五行) theory, Viscera and Bowels (臟腑) theory and Meridian and Collateral (經絡) theory stemmed from everyday practice, and Chinese people learn these theories from experience and observation. From the standpoint of Chinese people, particularly scholarly doctors [儒醫] such as Xu Lingtai, it was easy to debate medical theories. In contrast, Japanese traditional culture didn't have as long a history as China. Thus as a necessity, it was harder to disseminate traditional Chinese medicine theories in Japan. Yoshimasu Todo simplified it by cutting out the superfluous traditional Chinese medicine theory, so at that time it must have been shocking to the Japanese medical world's trends. The second, difference was due to viewpoints of talented experts. From the standpoint of Xu Lingtai, above all, medicine is just a learning, only a kind of technique, even more not a means of living. Xu Lingtai was concerned with the appearance of very talented experts such as 'great man' (偉人), and 'exceptional man' (奇士) who carried out medical research. Instead of cultivating a few talented people, Yoshimasu Todo tried to produce a large number of clinicians quickly who could treat ordinary people. The third was due to personality difference. As Xu Lingtai threw away Confucianism and studied medicine in his youth, although he had a critical attitude, he was always mild-mannered. Yoshimasu Todo always had a clearly critical and rebellious nature. Personality influenced their literary spirit and learning style, so although both advocated reactionism, the academic thought of Xu Lingtai was reformative and mild, while that of Yoshimasu Todo was revolutionary and fierce. Xu Lingtai and Yoshimasu Todo had considerably similar research domains and academic thought, so it is proper for them both to serve as examples for making a comparative study of medical history in China and Japan in 18th century.

• Advances in aircraft and spacecraft science
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• v.5 no.4
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• pp.431-444
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• 2018

Numerical simulations have been conducted to study the unstart/restart characteristics of an over-under turbine-based combined-cycle propulsion system (TBCC) inlet during the inlet transition phase. A dual-solution area exists according to the Kantrowitz theory, in which the inlet states may be different even with the same input parameters. The entire transition process was divided into five stages and the unstart/restart hysteresis loop for each stage was also obtained. These loops construct a hysteresis surface which separates the operating space of the engine into three parts: in which a) inlet can maintain a started state; b) inlet keeps an unstarted state; c) inlet state depends on its initial state. During the transition, the operation of the engine follows a certain order with different backpressures and splitter angles, namely control route, which may result in disparate inlet states. Nine control routes with different backpressures and transition stages were designed to illuminate the route-dependent behavior of the inlet. The control routes operating towards the unstart boundary can make the inlet transit from a started state into an unstarted one. But operating backward the same route cannot make the inlet restart, additional effort should be made.

• Journal of Korean Medical classics
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• v.22 no.2
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• pp.231-261
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• 2009

"Byunjeung-okham(辨證玉函)" is composed of four volumes, Eumjeung-yangjeungbyun(陰症陽症辨, Vol.1), Heojeungsiljeungbyeon(虛症實症辨, Vol.2), Sangjeunghajeungbyun(上症下症辨, Vol.3) and Jinjeunggajeungbyun(眞症假症辨, Vol.4) (卷之一 "陰症陽症辨", 卷之二 "虛症實症辨", 卷之三 "上症下症辨", 卷之四 "眞症假症辨"). It is based on the 74 types of disease symptoms, and compared to "Byunjeungrok(辨證錄)", it is rather brief and concise. Thus, its name, "Byunjeung-okham". This study researched vol.2, "Heojeungsiljeungbyun(虛症實症辨)", which is organized according to the deficiency and excess pattern of 20 disease patterns, such as cough. The disease pattern system mentioned in this book is unique compared with other disease pattern systems. The role of the kidney is especially emphasized, and the application of the Five-phase[五行] theory is very original. Consequently, it contributed greatly in the process of broadening the disease pattern system of Traditional Korean Medicine.

• Structural Engineering and Mechanics
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• v.67 no.4
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• pp.403-415
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• 2018

In the present study, nonlinear dynamic response of polymer-CNT-fiber multiscale nanocomposite plate resting on elastic foundations in thermal environments using the finite element method is performed. In this regard, the governing equations are derived based on Inverse Hyperbolic Shear Deformation Theory and von $K{\acute{a}}rm{\acute{a}}n$ geometrical nonlinearity. Three type of distribution of temperature through the thickness of the plate namely, uniform linear and nonlinear are considered. The considered element is C1-continuous with 15 DOF at each node. The effective material properties of the multiscale composite are calculated using Halpin-Tsai equations and fiber micromechanics in hierarchy. The carbon nanotubes are assumed to be uniformly distributed and randomly oriented through the epoxy resin matrix. Five types of impulsive loads are considered, namely the step, sudden, triangular, half-sine and exponential pulses. After examining the validity of the present work, the effects of the weight percentage of SWCNTs and MWCNTs, nanotube aspect ratio, volume fraction of fibers, plate aspect, temperature, elastic foundation parameters, distribution of temperature and shape of impulsive load on nonlinear dynamic response of CNT reinforced multi-phase laminated composite plate are studied in details.