• The Transactions of The Korean Institute of Electrical Engineers
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• v.63 no.3
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• pp.389-394
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• 2014

Two evolutionary gait generation methods for Cartesian and Joint coordinates space are compared to develop a fast locomotion for quadruped robots. GA(Genetic Algorithm) based approaches seek to optimize a pre-selected set of parameters for the locus of paw and initial position in cartesian coordinates space. GP(Genetic Programming) based technique generate few joint trajectories using symbolic regression in joint coordinates space as a form of polynomials. Optimization for two proposed methods are executed using Webots simulation for the quadruped robot which is built by Bioloid. Furthermore, simulation results for two proposed methods are analysed in terms of different coordinate spaces.

• Clinical and Experimental Pediatrics
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• v.50 no.9
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• pp.823-834
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• 2007

Interferon (IFN) alpha has been the first line therapy of chronic hepatitis B in children, but HBeAg seroconversion occurred in 26% of treated children compared to 11% of controls in multinational randomized controlled study. Recently, lamivudine was shown to be a potent inhibitor of Hepatitis B virus (HBV) reproduction both in HBeAg positive and in HBeAg negative (the pre-core mutant form) chronic hepatitis in randomized studies worldwide. Lamivudine therapy led to considerable improvement in the seroconversion rate of HBeAg in children with chronic hepatitis B, though long-term therapy resulted in the expansion of lamivudine-resistant mutant viruses. Combination therapy with lamivudine plus alpha-IFN does not seem to improve HBe Ag seroconversion. Above all, the most effective way to prevent hepatitis B is universal HBV vaccination.

• International Journal of Reliability and Applications
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• v.15 no.2
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• pp.151-161
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• 2014

Recently, the automotive industry has been introduced to ISO 26262 in November 2011 to address the necessity of safety risk from sensor to actuator by providing guidance in the form of requirements and processes. The malfunctioning behaviour of these systems could have significant impact on the safety of humans and/or the environment. Most of the modern automobiles are equipped with embedded electronic systems which include lots of Electronic Controller Units (ECUs), electronic sensors, signals, bus systems and coding. Due to the complex application in electrical, electronics and programmable electronics, the need to carry out detailed safety analyses which focuses on the potential risk of malfunction is crucial for automotive systems. In this paper, the international trends on pre and post introduction of ISO 26262 through publications will be analyzed as well as to take a glimpse in the activities for implementing this standard by the automotive manufacturers. The issues and challenges which have been occurring from implementing this standard also will be highlighted.

• Steel and Composite Structures
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• v.5 no.4
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• pp.327-343
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• 2005

The European Standards Organisation (CEN) has planned to develop a complete set of harmonized European building standards. The Eurocodes, being the design standards, form part of this total system of European standards, together with standards for fabrication and erection and product standards. After a period of experimental use of the ENV(European Pre Standard)-versions of the Eurocodes, these are now converted into official EN's (European Standards). Design of composite steel and concrete buildings and bridges is covered by Eurocode 4. An overview will be given of the historic development of Eurocode 4, the structure and contents of the EN version and the present status and planning for completion. The Eurocode treatment of some selected technical items will be presented in more detail.

• Journal of Astronomy and Space Sciences
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• v.26 no.4
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• pp.651-658
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• 2009

Nonlinear sliding surface design in variable structure systems for spacecraft attitude control problems is studied. A robustness analysis is performed for regular form of system, and calculation of actuator bandwidth is presented by reviewing sliding surface dynamics. To achieve non-singular attitude description and minimal parameterization, spacecraft attitude control problems are considered based on modified Rodrigues parameters (MRP). It is shown that the derived controller ensures the sliding motion in pre-determined region irrespective of unmodeled effects and disturbances.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.167.2-167
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• 2001

This paper presents guidance and control laws which guarantee a minimum fuel consumption and have obustness against various disturbances during a terminal-landing phase on the lunar surface. The nonlinear robust tracking control system is designed to track the reference profiles, which are expressed by exponential functions. An adjustment law in the tracking controller is given in the form of the differential equations with respect to the controller´s variable gains. Computer simulations are performed to examine the tracking accuracy, the robustness in a thrust failure mode, and the vertical soft landing at a pre-assigned point on the lunar surface. The results of numerical simulation show the effectiveness of the present control law.

• Journal of The Korean Astronomical Society
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• v.29 no.spc1
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• pp.259-259
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• 1996

Circumstellar peculiarities of the young Herbig Ae/Be stars are analyzed using high-resolution CCD spectroscopic data, obtained in 1991-1996 at the ESO and the Crimean Astrophysical Observatory (about 450 spectrograms). The results of investigation of the rapid line variability in H$\alpha$, H$\beta$, HeI 5876 and DNaI lines are presented for AB Am, HD 163296, HD 36112, HD 100546, and HD 50138. We conclude that the behaviour of these lines can be explained in the framework of the model containing an equatorially concentrated and azimuthally inhomogeneous stellar wind, and an external cool shell that occasionally looses matter in form of infall onto the star.

• The Journal of Korean Medicine
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• v.27 no.3 s.67
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• pp.132-144
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• 2006

Objectives: In order to improve our understanding of the meridian, it is necessary to analyze how meridian theory formed. In this regard, the primitive form of meridians requires further study. Methods: Data from the pre-Han and Han dynasties were used, as such data document primitive forms of the meridian. Results: 1. Some of the terminology of the primitive meridians did not include symmetrical terms such as hand, foot, yin and yang; instead, terms of travel area were used. 2. In the primitive meridians, most travel from the bottom to the top. 3. The twelve meridian system had not yet been introduced into the primitive system. 4. In the primitive meridians, only a few had branches. 5. In the primitive meridians, they did not have obvious connections with the five vital organs and the six viscera. Conclusions: Although the primitive meridian system differs from the modem, studying the primitive meridians may improve our understanding of the modem meridians.

• Journal of the Korean Society for Precision Engineering
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• v.18 no.3
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• pp.107-114
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• 2001

The durability of head/disk interface is an important issue for hard disk drives. Currently, there are several means of assessing the performance and integrity of the head/disk interface. In this work Track Average Amplitude(TAA) signal was used to analyzed the head/disk interface with respect to variations in disk velocity, slider pre-load and preformed scratch on the disk. Particularly, TAA variation due to disk defect in the form of a scratch was investigated.

• Journal of the Korean Society for Precision Engineering
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• v.13 no.5
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• pp.164-172
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• 1996

In hard and brittle materials as advanced ceramics indented by a hard indenter, the indenter's transition radius, was defined as critical radius which distinguishes the occurrence of the first plastic deformation from the elastic cracking as the first damaging event, is analytically and experimentally investigated. The analytical result is shown that the critical load, which not enlarge pre-existing cracks as the form of median crack beneath a indenter, is constant, and is determined by the order of $k_{IC}$$^{4}$ $P_{Y}$$^{3}$(where, $K_{IC}$ , $P_{Y}$are the fracture toughness of materials and the applied pressure by indenting, respectively). And the size of transiton radii were experimentally obtained with the similar values to the analytical results.lts..