• Journal of Sasang Constitutional Medicine
• /
• v.19 no.1
• /
• pp.148-159
• /
• 2007

1. Objectives The purpose of this study was to investigate the correlation of Metabolic syndrome(MetS) and Intima-media thickness(IMT) of common carotid artery with Sasang constitution. 2. Methods 197 subjects who had taken health examinations and diagnosis of Sasang constitution from Jan 1, 2006 to Dec 31, 2006 at East-west health examination center of Kyung-Hee medical center were included and underwent B-mode ultrasonography for measurement of intima-media thickness of common carotid arteries. MetS was defined by the criteria of the criteria of the National Cholesterol Education Program Adult Treatment Panel III. 3. Results and Conclusions Mean intima-media thickness of common carotid artery was significantly higher in subjects with MetS compared with control subjects($0.070{\pm}0.017$ vs $0.063{\pm}0.014cm$) and a significant trend towards increased IMT was observed with increasing numbers of metabolic syndrome components(r=0.331, p=0.000). After adjustment for age and sex, IMT of common carotid arteries was significantly different among three constitutional groups (Soyangin:$0.065{\pm}0.015cm$, Taeumin:$0.068{\pm}0.016cm$, Soeumin:$0.056{\pm}0.010cm$), however, after adjustment for age, sex and existence of metabolic syndrome, there was no significant different. But, factor of Taeumin was the effective determinant of the increase of mean IMT of common carotid arteries.

• Journal of Technology Innovation
• /
• v.17 no.1
• /
• pp.49-67
• /
• 2009

As technological capabilities have enhanced, the patterns of innovation activities of latecomer firms changed to post catch-up mode. The purpose of this research is to analyze the post catch-up innovation patterns of technology-intensive small and medium firms of Korea. The innovation patterns can be divided into three types: the technology deepening innovation type, the new technology based innovation type and the architectural innovation type. The characteristics of the technology deepening innovation type are cumulative technological learning and the integration of new generic technology and existing technologies. The characteristics of new technology based type are the acquisition and revelations of new basic knowledges from former incubating organizations such as large firms and universities. The characteristics of the architectural innovation type are the learning of system architecture knowledge from former organization and interactive learning with user firms. These post catch up innovations also have some general characteristics. They effectively exploited the windows of opportunities which are opened in the middle of technological paradigm change.

• Journal of the Korean Association of Geographic Information Studies
• /
• v.17 no.4
• /
• pp.156-166
• /
• 2014

As of 2014, KARI (Korea Aerospace Research Institute) operates two high-resolution satellites such as Kompsat-2 and Kompsat-3. Kompsat-3 has capability of in-track stereo images acquisition but it is quite limited because the stereo mode lowers the spatial coverage in a trajectory. In this paper we analyze the epipolar geometry from the heterogeneous Kompsat-2 and Kompsat-3 image combination to epipolar resample them for 3D spatial data acquisition. The analysis was carried out using the piecewise approach with RPCs (Rational Polynomial Coefficients) and the result showed the parabolic epipolar curve pattern. We also concluded that the third order polynomial transformation is required for epipolar image resampling. The resampled image pair showed 1 pixel level of y-parallax and can be used for 3D display and digitizing.

• Journal of the Korean Institute of Telematics and Electronics D
• /
• v.36D no.7
• /
• pp.42-49
• /
• 1999

In this paper, we proposed a simple measurement method to find the behaviors of the fiber-to-waveguide coupler. The polished fiber blocks and planar waveguides on silicon dioxide were fabricated independently and then optically coupled by physical pressure. Several kinds of polymer with different refractive indices were used for waveguide films. The proposed method makes it possible to measure the center wavelength, bandwidth, extinction ratio, and polarization dependence of the coupler during fabrication procedure. The wavelength sensitivity increased with refractive index of polymer. The symmetric planar waveguide structure and isotropic property of guiding materials reduced polarization dependent property. Insertion loss of the coupler was less than 0.5dB. It is expected that our measurement method is useful for developing various optical devices using evanescent coupling between polished fiber and planar waveguide such as optical modulators and filters etc.

• The Bulletin of The Korean Astronomical Society
• /
• v.41 no.2
• /
• pp.66.3-67
• /
• 2016

The Giant Magellan Telescope (GMT) will feature two interchangeable Gregorian secondary mirrors, an adaptive secondary mirror (ASM) and a fast-steering secondary mirror (FSM). The FSM has an effective diameter of 3.2 m and built as seven 1.1 m diameter circular segments, which are conjugated 1:1 to the seven 8.4m segments of the primary. Each FSM segment contains a tip-tilt capability for fine co-alignment of the telescope subapertures and fast guiding to attenuate telescope wind shake and mount control jitter. This tip-tilt capability thus enhances performance of the telescope in the seeing limited observation mode. As the first stage of the FSM development, KASI conducted a Phase 0 study to develop a program plan detailing the design and manufacturing process for the seven FSM segments. The GMTO-KASI team matured this plan via an internal review in May 2016 and the revised plan was further assessed by an external review in June 2016. In this poster, we present the technical aspects of the FSM development plan.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.17 no.12
• /
• pp.1356-1361
• /
• 2004

High temperature superconducting coated conductor has a structure of ///. The buffer layer consists of multi-layer, this study reports the deposition method and optimal deposition conditions of YSZ(Yttria-stabilized zirconia) layer which plays a important part in preventing the elements of substrate from diffusing into the superconducting layer. YSZ layer was deposited by DC reactive sputtering technique using water vapor for oxidizing deposited elements on substrate. To investigate optimal thickness of YSZ film, four YSZ/CeO$_2$/Ni samples with different YSZ thickness(130 nm, 260 nm, 390 nm, and 650 nm) were prepared. The SEM image showed that the surface of YSZ layer was getting to be rougher as YSZ layer was getting thicker and the growth mode of YSZ layer was columnar grain growth. After CeO$_2$ layer was deposited with the same thickness of 18.3 nm on each four samples, YBCO layer was deposited by PLD method with the thickness of 300 nm. The critical currents of four samples were 0, 6 A, 7.5 A, and 5 A respectively. This shows that as YSZ layer is getting thicker, YSZ layer plays a good role as a diffusion barrier but the surface of YSZ layer is getting rougher.

• Journal of Korean Association for Spatial Structures
• /
• v.7 no.6
• /
• pp.61-68
• /
• 2007

The hole for the insertion of the pin in the shank is exist at ball joint connection of the space frame. It brings about the brittle fracture caused by stress concentration. Consequently it cannot expect the deformation performance or energy absorption performance from ball joint connection. In this study we developed a new connection details which will increase the plastic deformation performance at ball joint connection and can absorb the error in construction, which expect the plastic deformation performance at the reduced shank without brittle fracture at the screw of bolt and pin. Also it's capacity is verified by the performance in numerical analysis and test. We confirmed bolt's plastic deformantion performance through controled shank and pin's area.

• Journal of the Institute of Electronics Engineers of Korea SD
• /
• v.41 no.12
• /
• pp.51-57
• /
• 2004

A simple fiber length measurement technique has been demonstrated by using a self-seeding laser oscillation of a Fabry-Perot laser diode. We induced a self-seeding laser oscillation through a closed-loop by adjusting the modulation frequency of a Fabry-Peort laser diode when the output optical pulse of the laser reinjected into the laser after passing through the closed-loop. The length of a fiber-under-test was calculated from the difference between my two modulation frequencies at which self-seeding laser oscillation occurs at a specific mode. We have experimentally confirmed the technique for various fiber lengths from 0.1 km to 75 km. The relative error between the measurement result of the proposed technique and that of a commercial instrument was less than 0.24 %. The repeatability of the proposed technique was better than 0.1 %.

• Proceedings of the IEEK Conference
• /
• 2002.06b
• /
• pp.61-64
• /
• 2002

We have optimally designed and implemented by a monolithic microwave integrated circuit(MMIC) the low noise amplifier(LNA) of 5.8GHz band composed of receiver front-end(RFE) in a on-board equipment system for dedicated short range communication using a depletion-mode GaAs MESFET. The LNA is provided with two active devices, matching circuits, and two drain bias circuits. Operating at a single supply of 3V and a consumption current of 18㎃, The gain at center frequency 5.8GHz is 13.4dB, Noise figure(NF) is 1.94dB, Input 3rd order intercept point(lIPS) is 3dBm, and Input return loss(5$_{11}$) and Output return loss(S$_{22}$) is -l8dB and -13.3dB, respectively. The circuit size is 1.2$\times$O.7$\textrm{mm}^2$.EX>.>.

• Journal of Electrochemical Science and Technology
• /
• v.11 no.4
• /
• pp.368-378
• /
• 2020

In the paper, corrosion behavior of T91 steel in different concentrations of NaHSO₃ solution was studied in combination with scanning electron microscope (SEM) and electrochemical measurements. The results showed that the steel exhibited active anodic dissolution characteristics in the solution, and NaHSO₃ concentration affected both cathodic and anodic behaviors. The steel surface was covered by intact corrosion products in the solutions, but the compactness and mechanical properties of the corrosion products degraded with the increase of NaHSO₃ concentration. In low-concentration NaHSO₃ solution the steel tended to undergo uniform corrosion with slight corrosion pits, but its corrosion mode gradually transited to localized corrosion as the NaHSO₃ concentration increased. The mechanical property degradation of the corrosion products caused by sulfur compounds and the pH decrease of the solution are the important factors to accelerating its corrosion process.