• Journal of the Korean Society of Clothing and Textiles
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• v.41 no.2
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• pp.326-340
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• 2017

This study explores the daily life of Korean designers in New York. We use in-depth interviews within the daily lives of participants to first reveal the time structure and meaning of everyday life. In this everyday time frame, this study reveals the content and meaning of life in New York, which is especially useful for fashion majors. Participants were 11 single Korean women around 30 years old working as designers in New York. Data was collected from Manhattan, New York, from November 2013 to February 2014 through the use of in-depth interviews and participant observation. Data collected daily life information on time usage, money, and energy that is first summarized into 229 meaning units. In the following, 55 central meanings were derived from stories common to behaviors for study participants and 19 subcategories were compressed into academic language. Finally, the generalized categories are divided into six categories of study life, work life, future life, family life, leisure life and fashion life. As a result of the first study, the daily time structure consisted of customary public time and personal repeat time. Second, the customary public time categories included the studying for 'Beginning to jump again to the best', 'Now working as a designer in New York', and future life expecting 'Future growing as a career woman'. Repeated personal time categories include family life: 'A single life of a lonely and poor gentile', leisure life: 'Healing life that is supported by abundant advanced culture', and fashion life: 'New York fashion life coexist with harmony'. Third, work was the center of everyday life for study participants versus fashion and leisure that were central to everyday life when not working.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.48 no.3
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• pp.354-361
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• 2015

Mitochondrial heat shock protein 75 (mtHSP75) is a member of the HSP90 family and plays essential roles in refolding proteins of the mitochondrial matrix. Mitochondria provide energy in the form of ATP and generate reactive oxygen species (ROS). Heat shock proteins (HSPs) are activated in response to stress, and protect cells. In this study, we characterized the mtHSP75 of the big-belly seahorse Hippocampus abdominalis. The protein (BsmtHSP75) is encoded by an open reading frame (ORF) of 2,157 nucleotides, has 719 amino acids (aa), and is of molecular mass 82 kDa. BsmtHSP75 has two functional domains, a histidine kinase-like ATPase (HATPase_c) domain (123-276 aa) and an HSP90 family domain (302-718 aa). BsmtHSP75 was expressed in all tested tissues of healthy seahorses. The ovary contained the highest transcription level, followed (in order) by the blood, brain, and muscle. Pouch tissue showed the lowest expression level. The expression of BsmtHSP75 was significantly (P<0.05) up-regulated on viral or bacterial challenge, suggesting that BsmtHSP75 plays a role in the immune defense against bacterial and viral pathogens.

• Journal of the Korean housing association
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• v.17 no.2
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• pp.125-134
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• 2006

The tightness of windows have devoted to the improvement of thermal insulation and energy saving in buildings. But it is known that this tightness causes some side effects such as low ventilation, low capacity to humidity and temperature control and these are not profitable for inhabitants. To act on these side effects, Korean traditional windows which are composed of Han-Ji(Koreand traditional paper) and Chang-Sal(Korean traditional wooden frame) have been studied to get a reasonable solutions for these problems. In this study, to compare the thermal and humidity control performance of current window(12 mm pair) and Korean traditional windows, frames which are made of existing window and Korean traditional windows are adapted to scale model house and then humidity and temperature of in and out of scale model house are measured and analysed. The results of this study are followings ; 1) When Korean traditional window charges 20cm(1/8 of total window area) from total window area, Han-Ji window has higher thermal insulation than that of existing window in daytime. There is the most big thermal difference when double faced with double-ply Han-Ji window is placed to mock-up house. In night-time, the temperature difference is very small so this means that Korean traditional window is good to cover direct sunlight in daytime and reduce the temperature of balcony. One faced with one-ply han-Ji window has the best humidity penetration performance among three type of Korean traditional windows. 2) When Korean window area enlarged to 40cm(1/4 of total window area), the function of 40cm width Han-Ji window is higher than that of 20cm's. This means that enlargement of Han-Ji window cover direct sunlight more and is more efficient in humidity penetration.

• Earthquakes and Structures
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• v.10 no.6
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• pp.1253-1272
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• 2016

For a nonlinear control system, there are many uncertainties, such as the structural model, controlled parameters and external loads. Although the significant progress has been achieved on the robust control of nonlinear systems through some researches on this issue, there are still some limitations, for instance, the complicated solving process, weak conservatism of system, involuted structures and high order of controllers. In this study, the computational structural mechanics and optimal control theory are adopted to address above problems. The induced norm is the eigenvalue problem in structural mechanics, i.e., the elastic stable Euler critical force or eigenfrequency of structural system. The segment mixed energy is introduced with a precise integration and an extended Wittrick-Williams (W-W) induced norm calculation method. This is then incorporated in the market-based control (MBC) theory and combined with the force analogy method (FAM) to solve the MBC robust strategy (R-MBC) of nonlinear systems. Finally, a single-degree-of-freedom (SDOF) system and a 9-stories steel frame structure are analyzed. The results are compared with those calculated by the $H{\infty}$-robust (R-$H{\infty}$) algorithm, and show the induced norm leads to the infinite control output as soon as it reaches the critical value. The R-MBC strategy has a better control effect than the R-$H{\infty}$ algorithm and has the advantage of strong strain capacity and short online computation time. Thus, it can be applied to large complex structures.

• Journal of the Society of Naval Architects of Korea
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• v.57 no.4
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• pp.213-220
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• 2020

In the present paper, implosion responses of two adjacent cylindrical tubes under external hydrostatic pressure were experimentally investigated. The cylinder models were fabricated of aluminium alloy 6061-T6 commercial tubes. In the experiment, a pair of two-cylinders were placed inside of a support frame in a medium-size pressure chamber, whose design pressure was 6.0MPa. The distance between the two-cylinders was 30 millimeter measured from outer shell at the mid-length. The implosion tests were performed with water and compressed nitrogen gas as the pressurizing media. The ambient static pressure of the chamber and local dynamic pressure near the two-imploded models were measured simultaneously. It was found that the energy released during an implosion from the first, weaker cylinder triggered the instability of the second, stronger cylinders. In other words, the resulting shock wave of the first implosive impact from the weaker cylinder could cause the premature failure of the neighboring stronger cylinders. The non-contact implosion phenomena from the two-cylindrical tube were clearly observed.

• Journal of Korean Association for Spatial Structures
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• v.16 no.2
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• pp.61-68
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• 2016

Behavior of RC(Reinforced-concrete) beam-column connections has been subjected to the earthquake loading has been determined by shear and attachment mechanism. However, since the shear and attachment are very fragile for cycle loadings. Through occurring plastic hinges at the beam, the column and the connection should remain elastic condition and the beam should dissipate the energy from the earthquake. This study was investigate on the seismic performance of 6 RC beam - column connections built with the high strength reinforcements (700MPa) based on design and detailing requirements in the ACI 318-05 Provision and KCI-07 appendix II. This is aimed to evaluate the effect of the high-strength reinforcements as used the beam-column connection members. The main comparisons were the seismic performance of the connections affect the seismic performance in terms of strength, stiffness and ductility, joint shear stress-strain. A total of 6 beam-column specimens were built with a 1/2 scale and subjected to the cyclic loadings. Main design considerations were the area of the longitudinal reinforcements of the beam and details of the beam-column joint designed based on the seismic code. Cyclic test results are given and recommendations for the usage of high strength reinforcements for the seismic design is provided.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.24 no.5
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• pp.129-135
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• 2010

It is well known that distributed generation(DG) system using renewable energy is an alternative to solve the problems which result from the exhaustion of fossil fuel and the environmental pollution. A PWM inverter is required for a power flow control in the DG systems. This paper proposes a SRF power flow control method considering grid impedance in grid-connected single-phase inverter systems. The proposed SRF power flow control method can provide a voltage-reference for the single-phase inverter even without any grid impedance estimation so that the single-phase inverter system could operate in stand-alone mode and grid-connected mode based on the known nominal value of grid impedance. Also independent controls of active and reactive power are achieved by the proposed control method. The effectiveness and the validity of the proposed control method are demonstrated through simulations. The simulation results show that the proposed control method can control properly power flow in grid-connected single-phase inverter systems.

• Steel and Composite Structures
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• v.34 no.1
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• pp.107-122
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• 2020

Moment resisting stub columns (MRSCs) have increasingly adopted in special moment-resisting frame (SMF) systems in steel building structures, especially in Asian countries. The MRSCs typically provide a lower deformation capacity compared to shear-panel stub columns, a limited post-yield stiffness, and severe strength degradation as adopting slender webs. A new MRSC design with cored configuration, consisting of a core-segment and two side-segments using different steel grades, has been proposed in the study to improve the demerits mentioned above. Several full-scale components of the cored MRSC were experimentally investigated focusing on the hysteretic performance of plastic hinges at the ends. The effects of the depths of the core-segment and the adopted reduced column section details on the hysteretic behavior of the components were examined. The measured hysteretic responses verified that the cored MRSC enabled to provide early yielding, great ductility and energy dissipation, enhanced post-yield stiffness and limited strength degradation due to local buckling of flanges. A parametric study upon the dimensions of the cored MRSC was then conducted using numerical discrete model validated by the measured responses. Finally, a set of model equations were established based on the results of the parametric analysis to accurately estimate strength backbone curves of the cored MRSCs under increasing-amplitude cyclic loadings.

• The Journal of the Acoustical Society of Korea
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• v.13 no.2
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• pp.76-85
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• 1994

A speech enhancement algorithm which attenuates nonstationary colored noise is presented In this paper. The algorithm consists of a stationary Kalman filter and the simple speech/nonspeech detector. While the conventional enhancement systems are focused on a stationary and/or white background noise, this study Is focused on the mort realistic nonstationary and nonwhite noise. An AR model-based vector Kalman filter is used as a noise suppression system and a short-time energy threshold logic is used as a speech/nonspeech classifier. For Kalman filtering. noise coefficients are estimated in the nonspeech frame, and speech coefficients are estimated by applying the EM iteration algorithm. Simulation results using the car noise are presented based on the signal-to-noise ratio and informal listening tests. According to the experimental results, background noises in the nonspeech frames are eliminated almost completely, while some distortions are noticed in the speech frames. The distortion becomes severer as the SNR is reduced to 0dB and -5dB. Intelligibility, however, is not degraded significantly.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.23 no.1
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• pp.111-119
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• 2010

Many researchers have studied on the optimal seismic design with the development of the computer. So far the application structure of most researches on the optimal seismic design was almost the moment resisting frame. Because the braced frames are the representative lateral load resisting system with the moment resisting frames, it is estimated that the effect on the practice will be great if it can is provided a design guideline through the development of optimal seismic design model for the braced frames. The purpose of this study is to propose the optimal seismic design model for the inverted V-type special concentrically braced frames considering the buckling of braces. The objective functions of this are to minimize the structural weight and maximize the total dissipated energy of the structure and the constraints of this are the strength conditions for the column, beam, brace and inter-story drifts condition. To verify the proposed model, it is applied to 2D steel concentrically braced frames of 3-story and 9-story.