• Journal of the Semiconductor & Display Technology
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• v.21 no.4
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• pp.132-137
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• 2022

In this paper, we have studied the quadrature error reduction for the single drive 3-axis MEMS Gyroscope. There was a limitation of the previous study which is the z-axis quadrature error was large. To reduce this value, design methodologies were presented. And the methodologies included a different mesh application, z-rate spring structure change, and mass compensation for balancing of the structure. We conducted the modal analysis, drive mode analysis and sense mode analysis using COMSOL Multiphysics. As a result, a drive resonant frequency was 26003 Hz, with the x-sense, y-sense, z-sense being 26749 Hz, 26858 Hz, 26920 Hz, respectively. And the Mechanical sensitivity was computed at 2000 degrees per second(dps) input angular rate while the sensitivity for roll, pitch, and yaw was computed 0.011, 0.012, and 0.011 nm/dps respectively. And z-axis quadrature error was successfully improved, 2.78 nm to 0.95 nm, which the improvement rate was about 66 %.

• Journal of the Korean Society of Food Culture
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• v.24 no.3
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• pp.308-314
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• 2009

In this study, we examined the composition of catechins, theaflavins and alkaloids in leaves during processing to fermented black tea, which is produced by withering, roll breaking, and fermentation of Korean Yabukida tea plant. In addition, we determined the optimal conditions for the production of fermented black tea. The average moisture content in fresh leaves was 70.85%, which dropped to 3.07% in fermented black tea at the last stage of production. When the leaves were analyzed by HPLC, seven types of catechins, four types of theaflavins and three types of alkaloids were identified. The levels of catechins, theaflavins, and alkaloids were then evaluated after being processed into fermented tea. From these experiments, we found that the level of theaflavins, which determines the property of the tea, increased during fermentation. This effect resulted from the change in EGCG, ECG, EGC, EC during the process of fermentation. We also found that the maximal amount of theaflavins was created after 1-2 hours of fermentation. Thus, our results imply that the best condition for producing fermented black tea would be to ferment for 1-2 hours.

• The Journal of the Korea institute of electronic communication sciences
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• v.19 no.2
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• pp.437-444
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• 2024

The rotational inertial navigation system can provide more accurate navigation information by mounting an IMU (Inertial Measurement Unit) on the gimbal and rotating the gimbal regularly to cancel out the errors of the IMU. However, when an attitude change occurs due to waves, the attitude error is not removed to 0 at the end of one cycle of the rotation procedure and causes a large position error. In this paper, considering this problem, we propose a method of stabilizing the external gimbal by rotating it based on the roll information of the vehicle. Based on simulation, the impact of waves is analyzed and the performance of external gimbal stabilization is verified.

• Korean Institute of Interior Design Journal
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• v.19 no.2
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• pp.107-116
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• 2010

In Europe, traditionally the low-rised buildings for public art museum have been constructed since the 18th century like any other buildings and these are because of the technical issue for construction difficulty. Even if the low-rised art museum buildings are still continued for it's construction, gradually the high-rised art museum buildings begin to be build due to the development of contemporary technology in high-dense modern urban space. This tendency of high-rised art museum building in recent years is expected to affect on the interior space of it and most of all the spatial change in conjunction with circulation system variation is remarkable. Because the circulation system in art museum means tourist's spatial experience and it normally controls the experience of knowledge in art museum. This study is to understand how the multi-floored art museums in Europe affect to the spatial structure and how this is related to the circulation system. And also the study raised an issue on what it's social meaning is. Through these analysis the study can provide the meaning of multi-floored art museum and basic indication in art museum planning. To understand this, the study calculated the number of stories, number of vertical circulation and number of ring-structure space. Also the study tired to use space syntax tools, which are connectivity, integration value, integration value in major space, integration value in vertical circulation and intelligibility value. those tools alculated topological transfiguration of the whole space.Throughout the study, it was concluded that the influence of high-rised art museum in Europe changed the spatial structure and circulation system. The topological center of art museum that has been the grand space since 18th century changed to the vertical circulation due to the it's roll of distributing visitors to each floor. It became a starting point of spatial deployment and experience in art museum.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.21 no.4
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• pp.683-690
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• 2012

In this work, the semi-active control of a large-sized bus suspension system with an MR damper was studied. An MR damper model that can aptly describe the hysteretic characteristics of an MR damper was adopted. Parameter values of the MR damper model were suitably modified by considering the maximum damping force of a passive damper used in the suspension system of a real large-sized bus. In addition, a fuzzy logic controller was developed for semi-active control of a suspension system with an MR damper. The vertical acceleration at the attachment point of the MR damper and the relative velocity between sprung and unsprung masses were used as input variables, while voltage was used as the output variable. Straight-ahead driving simulations were performed on a road with a random road profile and on a flat road with a bump. In straight-ahead driving simulations, the vertical acceleration and pitch angle were measured to compare the riding performance of a suspension system with a passive damper with that of a suspension with an MR damper. In addition, a single lane change simulation was performed. In the simulation, the lateral acceleration and roll angle were measured in order to compare the handling performance of a suspension system using a passive damper with that of a suspension system using an MR damper.

• The Korean Journal of Pharmacology
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• v.12 no.2 s.20
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• pp.43-49
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• 1976

The facts that $PGE_2$ produced diuresis in the rabbit when given into a lateral ventricle of the brain and that $PGF_{2{\alpha}}$ is abundantly found in the brain prompted us to investigate the effects of $PGF_{2{\alpha}}$ introduced directly into the ventricle on the renal function. $PGF_{2{\alpha}}$ given intraventriculary in doses of $10{\mu}g\;and\;100{\mu}g$ elicited prompt diuresis, 10-fold increase of sodium excretion and two-fold increment of potassium excretion. Free water reabsorption also increased along with the increased osmolar clearance. Neither renal plasma flow nor glomerular filtration rate did change significantly. This, along with the fact that the percentage of reabsorbed sodium filtered decreased from 99.5 to 93.9, indicates the tubular site of the diuretic and natriuretic action. Atropine pretreatment did not influence the renal effects of intraventricular $PGF_{2{\alpha}}$. Intravenously administered $PGF_{2{\alpha}}$ in doses of 30 to $100{\mu}g$ did not produce any significant change in renal function. Intraventricular $PGF_{2{\alpha}}$ had no effect on the systemic blood pressure, whereas intravenous administration brought about a transient hypotension. These observations suggest that $PGF_{2{\alpha}}$ induces diuresis and natriuresis via central mechanism, that the site of the action resides in renal tubules, and that the reabsorption of sodium is inhibited in the proximal tubule, possibly through mediation of certain humoral agent. Overall, it is suggested that $PGF_{2{\alpha}}$ might play a roll in regulating renal function through the center.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2012.10a
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• pp.818-821
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• 2012

This paper have analyzed the change of threshold voltage for conduction path of double gate(DG) MOSFET. The threshold voltage roll-off among the short channel effects of DGMOSFET have become obstacles of precise device operation. The analytical solution of Poisson's equation have been used to analyze the threshold voltage, and Gaussian function been used as carrier distribution to analyze closely for experimental results. The threshold voltages for conduction path have been analyzed for device parameters such as channel length, channel thickness, gate oxide thickness and doping concentration. Since this potential model has been verified in the previous papers, we have used this model to analyze the threshold voltage. Resultly, we know the threshold voltage is greatly influenced on the change of conduction path for device parameters of DGMOSFET.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.16 no.11
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• pp.2511-2516
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• 2012

This paper have analyzed the change of threshold voltage for conduction path of double gate(DG) MOSFET. The threshold voltage roll-off among the short channel effects of DGMOSFET have become obstacles of precise device operation. The analytical solution of Poisson's equation have been used to analyze the threshold voltage, and Gaussian function been used as carrier distribution to analyze closely for experimental results. The threshold voltages for conduction path have been analyzed for device parameters such as channel length, channel thickness, gate oxide thickness and doping concentration. Since this potential model has been verified in the previous papers, we have used this model to analyze the threshold voltage. Resultly, we know the threshold voltage is greatly influenced on the change of conduction path for device parameters of DGMOSFET.

• Transactions of the Society of Information Storage Systems
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• v.5 no.1
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• pp.47-52
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• 2009

Most hard disk drives that apply the ramp load/unload technology unload the heads at the outer edge of the disk while the disk is rotating. The load/unload includes the benefits as like an increased areal density, a reduced power consumption and an improved shock resistance. A lot of papers investigating the effects of the various load/unload parameters such as a suspension tab, a limiter, a ramp and air-bearing surface designs have been published. However, in previous researches, an effect of the suspension is not considered at each load/unload step. In this paper, we focus that a variation of the state matrix affects the load/unload performance on based on a state matrix that is a stiffness matrix of the suspension. Because the state matrix is related to the suspension at each load/unload step, to change the state matrix means the structural change of the suspension. Therefore, we investigated a range of a pitch static attitude(PSA) and a roll static attitude(RSA) for load/unload performance. We also analyzed an effect of the variation of the state matrix a range of load/unload velocity occurred a slider-disk contact. We determined the variation of the state matrix to improve the load/unload performance through comparison of each factor of state matrix.

• Archives of design research
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• no.16
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• pp.185-196
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• 1996

The series of ‘Dubonnet’poster is one of the masterpieces of Cassandre who was the leader of advertising poster in 1920's and 1930's. Orihinally it was a triptych, but it was developed as a serial work later through lettering and seasonal advertising posters. It was kept in circulation for more than two decades and issued in a variety of formats. In this thesis I tried to figure out the artistic character and uniqueness of Cassandre's poster by analyzing it with many different points of view of the poster, the stream of changing style and influence from the Avant-garde painting. In chapterII, objectively analyzing the series of‘Dubonnet’one by one, I examined the method that Cassandre used to deliver the concept of advertising and his message. The triptych, the first one of series of Dubonnet poster is witty, the slogan is a pun using the words dubo(doubt), bon(good), and Dubonnet, and the theme is treated as an animated sequence in the manner of a comic strip. In the following winter and summer seasonal advertising posters, the‘Dubonnet man’in the same position is enjoying the‘Dubonnet’, irrespective of the hazards of climate and season, There was a change towards 1929 that rectilinear design gave place to supple and undulating lines in Cassandre's posters. Seasonal advertising posters also showed the change, and the tendency of realistic and concrete elements of an expression was strengthened. In chapterIII, I studied three as main characters of Cassandre's poster. The first one is simple and geometric expression, second one is uniqueness of figures and the last one is important roll of lettering. Cassandre believed that there were fundamental differences between the function of a poster and that of a painting. He also recognized that the symbol was the essential element in the poster design, which would be simply and swiftly recognized. The recognition led him to simple design and bold geometric abstraction. He was a man who knew the value of copy in advertising and developed it fully in his simplified geometric compositions by integrating of letterforms and image. The‘Dubonnet man’is geometrized, almost featureless. This approach of rendering human beings was one that Cassandre had used from the early years, most notably in his posters for Dubonnet.