• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.40 no.9
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• pp.807-817
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• 2012

An optical payload needs to be validated its image performance after launched into orbit. The image performance was validated by observing star because ground site contains uncertainties caused by atmosphere, time of the year, and weather. Time Delayed and Integration(TDI) technique, which is mostly used to observe the ground, is going to be used to observe the selected stars. A satellite attitude scenario was also developed to observe the selected stars. The scenario is created to enable TDI to operate. Rotation angles of optical payload are determined in order for the selected stars to properly be passed at a desired angular velocity about rotation axis. The result of this research can be utilized to validate the quality of optical payload of a satellite in orbit. In addition, a quaternion for pointing selected stars is calculated minimizing the path from a given arbitrary attitude of satellite.

• Molecules and Cells
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• v.22 no.2
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• pp.146-153
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• 2006

Cell polarity is critical for the division, differentiation, migration, and signaling of eukaryotic cells. RAX2 of budding yeast encodes a membrane protein localized at the cell cortex that helps maintain the polarity of the bipolar pattern. Here, we designate SPAC6f6.06c as $rax2^+$ of Schizosaccharomyces pombe, based on its sequence homology with RAX2, and examine its function in cell polarity. S. pombe $rax2^+$ is not essential, but ${\Delta}rax2$ cells are slightly smaller and grow slower than wild type cells. During vegetative growth or arrest at G1 by mutation of cdc10, deletion of $rax2^+$ increases the number of cells failing old end growth just after division. In addition, this failure of old end growth is dramatically increased in ${\Delta}tea1{\Delta}rax2$, pointing to genetic interaction of $rax2^+$ with $tea1^+$. ${\Delta}rax2$ cells contain normal actin and microtubule cytoskeletons, but lack actin cables, and the polarity factor for3p is not properly localized at the growing tip. In ${\Delta}rax2$ cells, and endogenous rax2p is localized at the cell cortex of growing cell tips in an actin- and microtubule-dependent manner. However, ${\Delta}rax2$ cells show no defects in cell polarity during shmoo formation and conjugation. Taken together, these observations suggest that rax2p controls the cell polarity of fission yeast during vegetative growth by regulating for3p localization.

• Journal of The Korean Astronomical Society
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• v.37 no.4
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• pp.159-169
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• 2004

This is a proposal to probe local part of the interplanetary dust (IPD) cloud complex and retrieve mean volume emissivity of the local IPDs at mid-infrared wavelengths. This will be done by monitoring, with Infrared Camera (IRC) aboard the ASTRO-F, the annual modulation of the zodiacal emission. In pointing mode of the ASTRO-F mission the spacecraft can make attitude maneuvering over approximately ${\pm}1^{\circ}$ range centered at solar elongation $90^{\circ}$ in the ecliptic plane. The attitude maneuvering combined with high sensitivity of the IRC will provide us with a unique opportunity observationally to take derivatives of the zodiacal emission brightness with respect to the solar elongation. From the resulting differential of the brightness over the ${\pm}1^{\circ}$ range, one can directly determine the mean volume emissivity of the local IPDs with a sufficient accuracy to de-modulate the annual emissivity variations due to the Earth's elliptical motion and the dis-alignment of the maximum IPD density plane with respect to the ecliptic. The non-zero eccentricity ($e_{\oplus}$= 0.0167) of the Earth's orbit combined with the sensitive temperature dependence of the Planck function would bring modulations of amplitude at least $3.34\%$ to the zodiacal emission brightness at mid-infrared wavelengths, with which one may determine the IPD temperature T(r) and mean number density n(r) as functions of heliocentric distance r. This will in turn fix the power-law exponent $\delta$ in the relation $T(r) = T_o(r/r_o)^{-\delta}$ for the dust temperature and v in $n(r) = n_o(r/r_o)^-v$ for the density. We discuss how one may de-couple the notorious degeneracy of cross-section, density, reference temperature $T_o$ and exponent $\delta$.

• Molecules and Cells
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• v.26 no.1
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• pp.61-66
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• 2008

Cyclic AMP receptor protein (CRP) is allosterically activated by cAMP and functions as a global transcription regulator in enteric bacteria. Structural information on CRP in the absence of cAMP (apo-CRP) is essential to fully understand its allosteric behavior. In this study we demonstrated interdomain interactions in apo-CRP, using a comparative thermodynamic approach to the intact protein and its isolated domains, which were prepared either by limited proteolysis or using recombinant DNA. Thermal denaturation of the intact apo-CRP, monitored by differential scanning calorimetry, revealed an apparently single cooperative transition with a slight asymmetry. Combined with circular dichroism and fluorescence analysis, the thermal denaturation of apo-CRP could be interpreted as a coupled process involving two individual transitions, each attributable to a structural domain. When isolated individually, both of the domains exhibited significantly altered thermal behavior, thus pointing to the existence of non-covalent interdomain interactions in the intact apo-CRP. These observations suggest that the allosteric conformational change of CRP upon binding to cAMP is achieved by perturbing or modifying pre-existing interdomain interactions. They also underline the effectiveness of a comparative approach using calorimetric and structural probes for studying the thermodynamics of a protein.

• Land and Housing Review
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• v.2 no.1
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• pp.1-8
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• 2011

During the 1990's, five new towns were constructed around Seoul such as Bun-Dang and Il-San. These new towns are very popular since they were created based on systemic urban planning and they provide various residential amenities. Many people consider them livable cities. Taking such advantages, other small-scale new public and private developments continued around those new towns and consequently created 'agglomerated region with new development'. The most representative area is Bun-Dang and north-western Yong-In area which are formed along the Seoul-Busan expressway. This area is a mega-community having more than one million residents in 2005.Judging from recent development trends in the Seoul metropolitan area, it is expected that the formation of other 'agglomerated region with new development' would be continued for the time being. This study is aimed to analyze the residential environment of Bun-Dang and north-western Yong-In and find implications to the management of 'agglomerated region with new development'. The relevant existing studies have their limits, only focusing on analyzing current conditions and pointing out current problems. This study could be differentiated from the existing analyses in that it conducted comprehensive analyses on various factors that constitute urban residential environment. The conclusion of this study was derived from diverse analyses of current development condition, residential sites, regional transportation, awareness of residents, and oversee cases.

• Journal of Satellite, Information and Communications
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• v.5 no.2
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• pp.8-13
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• 2010

Satellite structure should be designed to accommodate and support safely the payload and equipments necessary for its own missions and to secure satellite and payloads from severe launch environments. The launch environments imposed on satellites are quasi-static accelerations, aerodynamic loads, acoustic loads and shock loads. Especially when optical payload is accommodated, satellite structure usually adopts the optical bench consisting of composite material not only to support and secure but also to guarantee good pointing stability against extreme thermal environments. This paper deals with optical bench and support structure which shall be designed to minimize the loads transferred to optical payloads from satellite.

• Journal of Astronomy and Space Sciences
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• v.23 no.1
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• pp.29-38
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• 2006

This paper presents an Image Motion Compensation (IMC) algorithm for the Korea's Communication, Ocean, and Meteorological Satellite (COMS)-1. An IMC algorithm is a priority component of image registration in Image Navigation and Registration (INR) system to locate and register radiometric image data. Due to various perturbations, a satellite has orbit and attitude errors with respect to a reference motion. These errors cause depointing of the imager aiming direction, and in consequence cause image distortions. To correct the depointing of the imager aiming direction, a compensation algorithm is designed by adapting different equations from those used for the GOES satellites. The capability of the algorithm is compared with that of existing algorithm applied to the GOES's INR system. The algorithm developed in this paper improves pointing accuracy by 40%, and efficiently compensates the depointings of the imager aiming direction.

• The Korean Journal of Ecology
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• v.26 no.4
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• pp.215-221
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• 2003

Ecological concepts were embedded in the old Korean maps and other documents. The concepts may represent ecological views which people had at the time. Through those ecological views, we propose that we can see a watershed concept in old Korean maps. We also discuss relevant records to understand the history of this concept. While many scholars have highlighted in the Baekdoodaegan frame only the pan of the mountain ranges, we are pointing out other perspectives. Our emphasis is that the concept is explicitly related to a watershed concept. An old Korean map shows that people at that time divided the Korean Peninsula into many watersheds, which was as early as 1402. We can even say that the idea is identified in a literal document written in the 12th century. It is hypothesized that a typical Korean landscape configuration was developed in the arrangement of village and surrounding landscape elements situated in a watershed. In addition, we suggest that the view had some negative effects on the current society. Even though the ideas of our ancestor are something to be praised, further study is needed to improve it in a wise manner.

• Journal of Korean Academy of Nursing
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• v.46 no.1
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• pp.29-38
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• 2016

Purpose: The Perinatal Post-Traumatic Stress Disorder Questionnaire (PPQ) was designed to measure post-traumatic symptoms related to childbirth and symptoms during postnatal period. The purpose of this study was to develop a translated Korean version of the PPQ and to evaluate reliability and validity of the Korean PPQ. Methods: Participants were 196 mothers at one to 18 months after giving childbirth and data were collected through e-mails. The PPQ was translated into Korean using translation guideline from World Health Organization. For this study Cronbach's alpha and split-half reliability were used to evaluate the reliability of the PPQ. Exploratory Factor Analysis (EFA), Confirmatory Factor Analysis (CFA), and known-group validity were conducted to examine construct validity. Correlations of the PPQ with Impact of Event Scale (IES), Beck Depression Inventory II (BDI-II), and Beck Anxiety Inventory (BAI) were used to test a criterion validity of the PPQ. Results: Cronbach's alpha and Spearman-Brown split-half correlation coefficient were 0.91 and 0.77, respectively. EFA identified a 3-factor solution including arousal, avoidance, and intrusion factors and CFA revealed the strongest support for the 3-factor model. The correlations of the PPQ with IES, BDI-II, and BAI were .99, .60, and .72, respectively, pointing to criterion validity of a high level. Conclusion: The Korean version PPQ is a useful tool for screening and assessing mothers' experiencing emotional distress related to child birth and during the postnatal period. The PPQ also reflects Post Traumatic Stress Disorder's diagnostic standards well.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.15 no.3
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• pp.700-712
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• 2011

Due to recently advanced electrical devices, human can access computer network regardless of working location or time restriction. However, currently widely used mouse, joystick, and trackball input system are not easy to carry and they bound user hands exclusively within working space. Those make user inconvenient in Ubiquitous environments.. In this paper, we propose multiple dimension human motion detection system based on wireless sensor networks. It is a portable input device and provides easy installation process and unbinds user hands during input processing stages. Our implemented system is comprised of three components. One is input unit that senses user motions and transmits collected data to receiver. Second is receiver that conveys the received data to application, which runs on server computer. Third is application that performs command operations according to received data. Experiments shows that proposed system accurately detect the characteristics of user arm motions and fully support corresponding input requests.