• Journal of Aerospace System Engineering
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• v.16 no.3
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• pp.99-104
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• 2022

Aircraft pylon connects the engine or external stores to the main wing, and transfers the load acting on the pylon to the main structure of the aircraft. In particular, it should perform the function of separating the external store mounted on the pylon in case of emergency or mission performance. At this time, if the separation of the external store is not performed properly due to peripheral air flow or functional problems during the separation process of the external store, it may seriously impact the survivability of the aircraft. For this reason, to apply an external attachment to an aircraft, it is necessary to prove the stability of the external attachment in the separation situation in advance. In this paper, we present the result of the ground separation test performed to confirm that the external fuel tank, which is an external attachment, can be safely separated from the pylon. As a result of the test, the separation movement of the external fuel tank was measured with a high-speed camera, and the stability of the separation of the external fuel tank from the pylon were confirmed through the ground separation test. Additionally, the test result provides basic data for the stability evaluation of the separation of external attachments in actual aircraft.

• Journal of Space Technology and Applications
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• v.2 no.1
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• pp.41-51
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• 2022

CubeSat is a satellite platform that is widely used not only for earth observation but also for space exploration. CubeSat is also used in magnetic field investigation missions to observe space physics phenomena with various shape configurations of magnetometer instrument unit. In case of magnetic field measurement, the magnetometer instrument should be far away from the satellite body to minimize the magnetic disturbances from satellites. But the accommodation setting of the magnetometer instrument is limited due to the volume constraint of small satellites like a CubeSat. In this paper, we investigated that the magnetic field interference generated by the cube satellite was analyzed how much it can affect the reliability of magnetic field measurement. For this analysis, we used a reaction wheel and Torque rods which have relatively high-power consumption as major noise sources. The magnetic dipole moment of these parts was derived by the data sheet of the manufacturer. We have been confirmed that the effect of the residual moment of the magnetic torque located in the middle of the 3U cube satellite can reach 36,000 nT from the outermost end of the body of the CubeSat in a space without an external magnetic field. In the case of accurate magnetic field measurements of less than 1 nT, we found that the magnetometer should be at least 0.6 m away from the CubeSat body. We expect that this analysis method will be an important role of a magnetic cleanliness analysis when designing a CubeSat to carry out a magnetic field measurement.

• Korean Journal of Social Welfare Studies
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• v.42 no.2
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• pp.123-153
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• 2011

This study tries to categorize innovation types for social welfare organizations and investigate the level of innovation in each type in practical field. Firstly, this study scrutinizes the concept and classification's criterias of innovation. Secondly, this study reviews not only classification of innovation in profit organization but also several researches of innovation in service industry and public sectors, and finally, this study makes a suggestion of innovations' classification that is applicable for social welfare organizations. Based on this suggestion, fifteen questions are designed to ask the innovative activities in the organizations. And total 496 respondents from 116 organizations answered these questionnaire. The outcomes of this survey were substantiated by second data through converted procedures to mean value of organizations. Consquently, service innovation, administrative innovation and human resource innovation, proposed based on theoretical review, were subdivided into six categories such as service innovation, structural innovation, internal and efficiency innovation, marketing and communication innovation, external and employment innovation and evalution and mission innovation. The mean value of service(mean=14.7) and marketing innovation(mean=13.3) are higher than other type of innovations, which shows the aspect of innovative activities in social welfare organizations. Based on this result, we can get the directions of following study in investigating innovation of social welfare organization.

• The Bulletin of The Korean Astronomical Society
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• v.46 no.2
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• pp.57.4-58
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• 2021

Asteroids have undergone various processes such as impacts, space weathering, and thermal evolution. Because they expose their surfaces to space without atmosphere, these evolutional processes have been recorded directly on their surfaces. The remote-sensing observations have been conducted to reveal these evolutional histories of the target asteroids. For example, crater and boulder distributions are unambiguous evidence for past nondestructive impacts with other celestial bodies. Multiband and spectroscopic observations have revealed space-weathering history (as well as compositions). Whereas most physical quantities have been examined intensively using spacecraft and telescopes, only a little has been studied on "the grain size". It is one of the fundamental physical quantities for diagnosing the collisional and thermal history of asteroids. Our group has conducted polarimetric research of asteroids (as well as Moon [1]) to determine the particle size and further investigate the evolutional histories of target asteroids [2],[3]. For example, the existence of regolith on an S-type asteroid, Toutatis, was suggested almost twenty years before space exploration [4]. Moreover, we reported that near-Sun asteroids indicate a signature of submillimeter grains, which could be created by a thermal sintering process by solar radiation [5]. However, it is important to note that in-situ polarimetry has not been reported on the asteroid surface, although the Korean Lunar Exploration Program aims to do polarimetry on the lunar surface [6]. Therefore, it is expected that the polarizer mounted on the Korean Apophis spacecraft can make the first estimate of the grain size and its regional variation over the Apophis surface. In this presentation, we outline research of S-type asteroid surfaces through remote-sensing observations and consider the role of polarimetry. Based on this review, we consider the purpose, potentiality, and strategy of the polarimetry using the onboard device for the Apophis spacecraft. We will report a possible polarization phase curve of Apophis estimated from ordinary chondrites and past observational data of S-type asteroids, taking account of the space weathering effect. Based on this estimation, we will consider the strategy of how to determine the particle size (and space weathering degree) of the Apophis surface. We will also mention the detectability of dust hovering on the surface.

• Korean Journal of Remote Sensing
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• v.39 no.6_2
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• pp.1541-1551
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• 2023

Radiometric calibration is a fundamental step in ocean color remote sensing since the step to derive solar radiance spectrum in visible to near-infrared wavelengths from the sensor-observed electromagnetic signals. Generally, satellite sensor suffers from degradation over the mission period, which results in biases/uncertainties in radiometric calibration and the final ocean products such as water-leaving radiance, chlorophyll-a concentration, and colored dissolved organic matter. Therefore, the importance of radiometric calibration for the continuity of ocean color satellites has been emphasized internationally. This study introduces an approach to improve the radiometric calibration algorithm for the visible bands of the Geostationary Ocean Color Imager-II (GOCI-II) satellite with a focus on stability. Solar Diffuser (SD) measurements were employed as an on-orbit radiometric calibration reference, to obtain the continuous monitoring of absolute gain values. Time series analysis of GOCI-II absolute gains revealed seasonal variations depending on the azimuth angle, as well as long-term trends by possible sensor degradation effects. To resolve the complexities in gain variability, an azimuth angle correction model was developed to eliminate seasonal periodicity, and a sensor degradation correction model was applied to estimate nonlinear trends in the absolute gain parameters. The results demonstrate the effects of the azimuth angle correction and sensor degradation correction model on the spectrum of Top of Atmosphere (TOA) radiance, confirming the capability for improving the long-term stability of GOCI-II data.

• Archives of Craniofacial Surgery
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• v.25 no.2
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• pp.62-70
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• 2024

Background: The management of cleft lip and palate aims at improving the patient's aesthetic and functional outcomes. Delaying primary repair can disrupt the patient's functional status. Long-term follow-up is essential to evaluate the need for secondary repair or revision surgery. This article presents the epidemiology of cleft lip and palate, including comprehensive patient characteristics, the extent of delay, and secondary repair at our institutional center, the Bandung Cleft Lip and Palate Center, Faculty of Medicine, Universitas Padjadjaran, Bandung, Indonesia. Methods: This retrospective study aimed to determine the epidemiology and recurrence rates of cleft lip and palate at the Bandung Cleft Lip and Palate Center, Indonesia, from January 2007 to December 2021. The inclusion criteria were patients diagnosed with cleft lip and/or palate. Procedures such as labioplasty, palatoplasty, secondary lip and nasal repair, and alveolar bone grafting were performed, and data on recurrence were available. Results: In total, there were 3,618 patients with cleft lip and palate, with an age range of 12 months to 67 years. The mean age was 4.33 years, and the median age was 1.35 years. Males predominated over females in all cleft types (60.4%), and the cleft lip was on the left side in 1,677 patients (46.4%). Most cases were unilateral (2,531; 70.0%) and complete (2,349; 64.9%), and involved a diagnosis of cleft lip and palate (1,981; 54.8%). Conclusion: Delayed primary labioplasty can affect daily functioning. Primary repair for patients with cleft lip and palate may be postponed due to limited awareness, socioeconomic factors, inadequate facilities, and varying adherence to treatment guidelines. Despite variations in the timing of primary cleft lip repair (not adhering to the recommended protocol), only 10% of these patients undergo reoperation. Healthcare providers should prioritize the importance of the ideal timing for primary repair in order to optimize physiological function without compromising the aesthetic results.

• Journal of Hospice and Palliative Care
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• v.4 no.2
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• pp.145-153
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• 2001

Purpose : This study was conducted to describe the attitude of hospital staff toward the hospice program. The purpose of this study was to promote the extension and organization of hospice activities to include hospital staff. Method : This is a descriptive study using a survey method. The subjects for this study were the nurses, physicians, technicians, and support staff at Wonju Christian Hospital. Using a stratified sampling method based on position of staff, the researchers recruited 430 staff members as the sample for this study. Data collection was done through a questionnaire developed by the researchers. The data were analyzed using descriptive statistics and content analysis. Findings : 1)Ninety seven percent (n=417) of the subjects understood the concept of hospice care, and 97.4% (n=419) answered that dying patients should be respected. When considering the hospice team, the subjects of this study indicated that the team should include family members (n=245), physicians (n=77), pastors (n=41), and nurses (n=34), in that order of priority. 2) When asked to indicate priorities for systematic operation of a hospice program, the subjects indicated that the highest priority was "setting up a team for hospice service(31.4%)", followed by "setting up a hospice ward(28.6%)". Sixty seven percent(n=289) recognized the importance of the hospice activities provided by the volunteers, and 85.3%(n=367) intended to use the hospice service of the hospital. The highest merit of hospital-based hospice program is 'acomplishment of mission'. 3) The average score on attitude toward death was 2.84(maximum=4), and the best needful service except hospitalization is 'constructing of support system'. Conclusion : Most of the staff at Wonju Christian Hospital perceive the necessity for systematic hospice activities, and that to achieve this goal, administrative and structural support at the hospital governance level is the first necessity. The results of this study could be useful for any hospital which is in the first stages of setting up and promoting a hospice program.

• Atmosphere
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• v.12 no.4
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• pp.20-42
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• 2002

Based on the "Mid to Long Term Plan for Space Development", a project to launch COMeS (Communication, Oceanography, and Meteorological Satellite) into the geostationary orbit is undergoing. Accordingly, KMA (Korea Meteorological Administration) has defined the meteorological missions and prepared the user requirements to fulfill the missions. To make a realistic user requirements, we prepared a first draft based on the ideal meteorological products derivable from a geostationary platform and sent the RFI (request for information) to the sensor manufacturers. Based on the responses to the RFI and other considerations, we revised the user requirement to be a realistic plan for the 2008 launch of the satellite. This manuscript introduces the revised user requirements briefly. The major mission defined in the revised user requirement is the augmentation of the detection and prediction ability of the severe weather phenomena, especially around the Korean Peninsula. The required payload is an enhanced Imager, which includes the major observation channels of the current geostationary sounder. To derive the required meteorological products from the Imager, at least 12 channels are required with the optimum of 16 channels. The minimum 12 channels are 6 wavelength bands used for current geostationary satellite, and additional channels in two visible bands, a near infrared band, two water vapor bands and one ozone absorption band. From these enhanced channel observation, we are going to derive and utilize the information of water vapor, stability index, wind field, and analysis of special weather phenomena such as the yellow sand event in addition to the standard derived products from the current geostationary Imager data. For a better temporal coverage, the Imager is required to acquire the full disk data within 15 minutes and to have the rapid scan mode for the limited area coverage. The required thresholds of spatial resolutions are 1 km and 2 km for visible and infrared channels, respectively, while the target resolutions are 0.5 km and 1 km.

• Journal of Astronomy and Space Sciences
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• v.22 no.3
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• pp.329-352
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• 2005

Long term observations of full-disk Lyman-o irradiance have been made by the instruments on various satellites. In addition, several sounding rockets dating back to the 1950s and up through the present have measured the $Lyman-{\alpha}$ irradiance. Previous full disk $Lyman-{\alpha}$ images of the sun have been very interesting and useful scientifically, but have been only five-minute 'snapshots' obtained on sounding rocket flights. All of these observations to date have been snapshots, with no time resolution to observe changes in the chromospheric structure as a result of the evolving magnetic field, and its effect on the Lyman-o intensity. The $Lyman-{\alpha}$ Imaging Solar Telescope(LIST) can provide a unique opportunity for the study of the sun in the $Lyman-{\alpha}$ region with the high time and spatial resolution for the first time. Up to the 2nd year development, the preliminary design of the optics, mechanical structure and electronics system has been completed. Also the mechanical structure analysis, thermal analysis were performed and the material for the structure was chosen as a result of these analyses. And the test plan and the verification matrix were decided. The operation systems, technical and scientific operation, were studied and finally decided. Those are the technical operation, mechanical working modes for the observation and safety, the scientific operation and the process of the acquired data. The basic techniques acquired through the development of satellite based solar telescope are essential for the construction of space environment forecast system in the future. The techniques which we developed through this study, like mechanical, optical and data processing techniques, could be applied extensively not only to the process of the future production of flight models of this kind, but also to the related industries. Also, we can utilize the scientific achievements which are obtained throughout the project And these can be utilized to build a high resolution photometric detectors for military and commercial purposes. It is also believed that we will be able to apply several acquired techniques for the development of the Korean satellite projects in the future.

• Journal of Korean Home Economics Education Association
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• v.21 no.2
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• pp.83-107
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• 2009

The purpose in this study was to provide a basic resource for enhancing teachers' professional competence by examining how the Home Economics(HE) teachers had formed, developed, and introspected the pedagogical content knowledge in the HE classes of secondary schools. Data were collected through in-depth interviews with six HE teachers working at secondary schools. NVivo program, a kind of CAQDAS was used to analyze the data inductively. This study revealed that the HE teachers reflectively introspected the pedagogical content knowledge in Home Economics Education(H-PCK) as follows: First, as for knowledge of perspective on Home Economics Education(HEE), the research participants encouraged students to solve practical problems regarding the objective of HEE. They tried to foster the students' critical thinking ability related to the daily life. They made eager efforts to achieve the mission of HEE as a practical science. Second, as for knowledge of HE curriculum, the research participants mentioned that there was lack of systematic approach concerned with curriculum development. While reorganizing, they always paid attention to its relation to the students' daily lives, to the relationship between the curriculum contents and the social context. Third, as for knowledge of teaching strategies on practical problem-based instruction, the research participants developed the practical problem-based instruction skills. They mentioned students' difficulties in relating the practical problem-based instruction, too. Fourth, regarding knowledge of context, as teachers mostly prepared for progressed instruction alone without communicating with colleagues in the same school, they yearned for and also formed networks with other HE teachers in order to overcome their limitations.