• ETRI Journal
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• 제31권4호
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• pp.478-480
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• 2009

The design of a CMOS clamped-clamped beam resonator along with a full custom integrated differential amplifier, monolithically fabricated with a commercial 0.35 ${\mu}m$ CMOS technology, is presented. The implemented amplifier, which minimizes the negative effect of the parasitic capacitance, enhances the electrical MEMS characterization, obtaining a $48{\times}10^8$ resonant frequency-quality factor product ($Q{\times}f_{res}$) in air conditions, which is quite competitive in comparison with existing CMOS-MEMS resonators.

• 천문학회지
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• 제53권3호
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• pp.69-75
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• 2020

We study the photometric phase curves for the planets of our solar system which can be considered as a prototypical non-compact planetary system. We focus on modeling the small variations caused by three effects: reflection, ellipsoidal, and Doppler beaming. Theoretical predictions for these photometric variations are proposed, considering a hypothetical external observer. Unlike similar studies of multi-planetary systems, the physical and geometrical parameters for each planet of the solar system are well-known. Therefore, we can accurately evaluate the relationships that shape the planetary light curves for a fictitious external observer. Our results suggest that, for all planets, the ellipsoidal effect is very weak while the Doppler beaming effect (DBE) is, in general, dominant. In fact, the DBE seems to be the principal cause of variations of the light curves for the planets of the solar system. However, for Mercury and Venus the Doppler beaming and reflection effects have similar amplitudes. The phase curves obtained for the planets of the solar system show new interesting features of interest for the study of other non-compact planetary systems.

• ALGAE
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• 제24권4호
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• pp.213-229
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• 2009

A monographic reassessment of Padina Adanson species from the Gulf of California was developed based on an exhaustive review of the character and characters states that have been used to delimit species in recent and historically valuable collections. Eight names (P. caulescens Thivy in Taylor, P. concrescens Thivy in Taylor, P. crispata Thivy in Taylor, P. durvillaei Bory Saint-Vincent, P. gymnospora [Kutzing] Sonder, P. mexicana Dawson, P. tetrastromatica Hauck and P. vickersiae Hoyt in Howe) were reported from the region. An analysis of 1,200 specimens led to the conclusion that only three species (P. durvillaei, P. concrescens and P. mexicana) can be recognized for the area based on four discriminating characters: presence of calcium carbonate in the cell wall; number of medullary cell layers in the basal area; number of medullary cell layers in the middle part and presence/absence of cortical cells. Comparative analysis of the species in the Gulf of California in relation to other recently evaluated species has shown a clear distinction among them suggesting Padina species were overestimated in our area.

• BMB Reports
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• 제41권1호
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• pp.72-78
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• 2008

Human NeuNAc-9-P synthase is a two-domain protein with ability to synthesize both NeuNAc-9-P and KDN-9-P. Its mouse counterpart differs by only 20 out of 359 amino acids but does not produce KDN-9-P. By replacing the AFL domain of the human NeuNAc-9-P synthase which accommodates 12 of these differences, with the mouse AFL domain we examined its importance for the secondary KDN-9-P synthetic activity. The chimeric protein retained almost half of the ability of the human enzyme for KDN-9-P synthesis while the NeuNAc-9-P production was reduced to less than 10%. Data from the homology modeling and the effect of divalent ions and temperature on the enzyme activities suggest conformational differences between the human and mouse AFL domains that alter the shape of the cavity accommodating the substrates. Therefore, although the AFL domain itself does not define the ability of the human enzyme for KDN-9-P synthesis, it is important for both activities by aiding optimal positioning of the substrates.

• Steel and Composite Structures
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• 제4권3호
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• pp.189-209
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• 2004

The commonly used seismic design procedures to evaluate the maximum effect of both horizontal components of earthquakes, namely, the Square Root of the Sum of the Squares (SRSS) and the 30-percent (30%) combination rules, are re-evaluated. The maximum seismic responses of four three-dimensional moment resisting steel frames, in terms of the total base shear and the axial loads at interior, lateral and corner columns, are estimated as realistically as possible by simultaneously applying both horizontal components. Then, the abovementioned combination rules and others are evaluated. The numerical study indicates that both, the SRSS rule and the 30% combination method, may underestimate the combined effect. It is observed that the underestimation is more for the SRSS than for the 30% rule. In addition, the underestimation is more for inelastic analysis than for elastic analysis. The underestimation cannot be correlated with the height of the frames or the predominant period of the earthquakes. A basic probabilistic study is performed in order to estimate the accuracy of the 30% rule in the evaluation of the combined effect. Based on the results obtained in this study, it is concluded that the design requirements for the combined effect of the horizontal components, as outlined in some code-specified seismic design procedures, need to be modified. New combination ways are suggested.

• Earthquakes and Structures
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• 제18권5호
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• pp.609-623
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• 2020

This paper presents a displacement-based seismic design procedure for new structures with fluid viscous dampers and/or for existing structures, where these devices are required as a retrofit measure and damage control. To consider the non-proportional damping produced by these devices in a conventional modal spectral analysis, the effect of the fluid viscous dampers is approximated as the sum of a proportional damping matrix and a complementary matrix which is representative of non-proportional damping matrix. To illustrate the application of this procedure and evaluate the performance of structures designed with the procedure proposed, five regular plane frames: 8, 12, 17, 20 and 25-storey, and an 8-storey building are designed. The seismic demands used for design and validation were the records obtained at the SCT site during the 1985 Michoacan earthquake, and that of the 2017 Morelos - Puebla earthquake obtained at the Culhuacan site, both stations located on soft soil sites. To validate the procedure proposed, the performances and damage distributions used as design targets were compared with the corresponding results from the nonlinear step-by-step analyses of the designed structures subjected to the same seismic demands.

• 패션비즈니스
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• 제10권4호
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• pp.114-129
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• 2006

This purpose of this study is to research on the influence on the creation of young generation's street fashion of pop stars focused on pop music given the fact that fashion can be created by popular culture in this multi-media era. Also, this study is to provide useful data for the activation of the creation of young fashion culture and the fashion industry through pop stars' fashion. The pop stars' fashion that has affected young street fashion is as follows : Elvis Presley's rock'n'roll style, Beatles' mods style, Janis Joplin's hippy style, Sex Pistols's punk style, Madonna's boy-toy and corset style, Michael Jackson's androgynous style, Puff Daddy and L.L Cool J's hip-hop style, Bob Marley's reggae style, Spice Girls, Jennifer Lopez and Britney Spears's sexy style. The young street fashion culture of pop stars and its industrial meaning withdrawn from the above are as follows : Creation of a fashion icon, Creation of anti-fashion, Liberation of a sex role, Costume play culture, Activation of the young fashion industry through star marketing.

• Wind and Structures
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• 제25권6호
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• pp.569-588
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• 2017

The aim of this paper is to present a method to obtain the dynamic response of a wind turbine tower in time domain by means of the generation of time series and to estimate the associated fatigue damage by means of a Rainflow counting algorithm. The proposed method is based on assuming the vortex shedding is a bidimensional phenomena and on following a classical modal superposition method to obtain the structure dynamic response. Four different wind turbine tower geometric configurations have been analyzed in a range of usual wind velocities and covering extreme wind velocities. The obtained results have shown that, depending on the turbulence intensity and the mean wind velocity, there are tower geometric configurations more advantageous from the fatigue load standpoint. Consequently, the presented model can be utilized to define assembly strategies oriented to fatigue damage minimization.

• Geomechanics and Engineering
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• 제14권1호
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• pp.51-60
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• 2018

The foundations are classified into shallow and deep, which have important differences: in terms of geometry, the behavior of the soil, its structural functionality, and its constructive systems. The shallow foundations may be of various types according to their function; isolated footings, combined footings, strip footings, and slabs foundation. The isolated footings are of the type rectangular, square and circular. The combined footing may be rectangular, trapezoidal or T-shaped in plan. This paper presents a new model for T-shaped combined footings to obtain the most economical contact surface on the soil (optimal dimensioning) to support an axial load and moment in two directions to each column. The new model considers the soil real pressure, i.e., the pressure varies linearly. The classical model uses the technique of test and error, i.e., a dimension is proposed, and subsequently, the equation of the biaxial bending is used to obtain the stresses acting on each vertex of the T-shaped combined footing, which must meet the conditions following: The minimum stress should be equal or greater than zero, and maximum stress must be equal or less than the allowable capacity that can withstand the soil. To illustrate the validity of the new model, numerical examples are presented to obtain the minimum area of the contact surface on the soil for T-shaped combined footings subjected to an axial load and moments in two directions applied to each column.

• Geomechanics and Engineering
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• 제14권1호
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• pp.61-69
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• 2018

The first part shows the optimal contact surface for T-shaped combined footings to obtain the most economical dimensioning on the soil (optimal area). This paper presents the second part of a new model for T-shaped combined footings, this part shows a the mathematical model for design of such foundations subject to axial load and moments in two directions to each column considering the soil real pressure acting on the contact surface of the footing with one or two property lines restricted, the pressure is presented in terms of an axial load, moment around the axis "X" and moment around the axis "Y" to each column, and the methodology is developed using the principle that the derived of the moment is the shear force. The classic model considers an axial load and a moment around the axis "X" (transverse axis) applied to each column, i.e., the resultant force from the applied loads is located on the axis "Y" (longitudinal axis), and its position must match with the geometric center of the footing, and when the axial load and moments in two directions are presented, the maximum pressure and uniform applied throughout the contact surface of the footing is considered the same. To illustrate the validity of the new model, a numerical example is presented to obtain the design for T-shaped combined footings subjected to an axial load and moments in two directions applied to each column. The mathematical approach suggested in this paper produces results that have a tangible accuracy for all problems.