• Journal of Positioning, Navigation, and Timing
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• v.11 no.4
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• pp.327-332
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• 2022

The Korea Augmentation Satellite System (KASS) is the Satellite-Based Augmentation System (SBAS) under development in Korea. KASS navigation service support navigation Safety of Life (SoL) service. KASS signal provides corrections to Global Positioning System (GPS) data received from KASS Reference Stations (KRS) and is broadcast form Geostationary Earth Orbiting (GEO) satellites to KASS users and is used by GPS/SBAS user equipment to improve the accuracy, availability, continuity and integrity of the navigation solution. Seven KRS's collect the satellite data and send them to the KASS Processing Stations (KPS) for the generation of the corrections and the monitoring the integrity. For performing its computation the KPS needs to know accurate and reliable KRS antennas coordinates. These coordinates are provided as configuration parameters to the KPS. This means that the reference frame in which the KPS work is the one represented by the set of coordinates provided as input. Therefore, the activity to maintain the accuracy of the KRS antenna coordinates is necessary, knowing that coordinates can evolve due to earth plates movements or earthquakes. In this paper, we analyzed the geodetic survey results for KRS antenna coordinates from Site Acceptance Test (SAT) #1 in December 2020 to August 2022. In the future, it is expected that these activities and planning for KRS coordinates maintenance will be produced and provided to KASS system operators for KPS configuration updates during the KASS lifetime of 15 years. Through these maintenance activities, it is expected that monitoring and analysis of unpredictable events such as earthquakes and seism will be possible in the future.

• Journal of the Korean Society of Systems Engineering
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• v.14 no.1
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• pp.13-18
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• 2018

Plant Engineering is a series of activities going through following life cycle phases: planning, basic design, detailed design, procurement and construction, commissioning, operation and maintenance, to produce a target product. From among these phases of plant engineering life cycle, a detailed design phase is an important phase producing final design deliveries. Luckily, through technical co-operation and experiences of constructing plants, large Korean engineering companies have accumulated know-hows of efficient detailed designs. However, smaller engineering companies have less experience of performing detailed designs so there is always a risk of causing design errors in the detailed design phase. To mitigate the risk of design errors in the detailed design phase, it is necessary to systematize a concrete activity model of a detailed design phase. In this paper, we have developed a prototype of a detailed design activity model through a widely used function modeling methodology called IDEF0.

• Journal of the Korean Home Economics Association
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• v.48 no.6
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• pp.133-147
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• 2010

This study aimed to identify the dimensions of successful aging, as perceived by elderly Koreans, and to test qualitatively the elders' optimization of selection and compensation strategies in a social activity context. The results were as follows: First, the most important part of life fulfillment and regret was family and work. Second, social activity played a role in self-actualization and physiological needs. Moreover, it contributed to the elders' physical and mental health maintenance. Third, the elderly effectively participated in social activities by optimizing their selection and compensation strategies. Fourth, the elderly realized they are growing old, but considered it as a natural process. In addition, some participants suggested retirement age should be raised, but others were against this idea. Finally, elders thought successful aging means having a sufficient and independent life in old age. Thus, the elderly required good health, economic security, and a positive attitude for aging successfully.

• BMB Reports
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• v.55 no.4
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• pp.161-165
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• 2022

The mechanistic target of rapamycin (mTOR) regulates numerous extracellular and intracellular signals involved in the maintenance of cellular homeostasis and cell growth. mTOR also functions as an endogenous inhibitor of autophagy. Under nutrient-rich conditions, mTOR complex 1 (mTORC1) phosphorylates the ULK1 complex, preventing its activation and subsequent autophagosome formation, while inhibition of mTORC1 using either rapamycin or nutrient deprivation induces autophagy. Autophagy and proteasomal proteolysis provide amino acids necessary for protein translation. Although the connection between mTORC1 and autophagy is well characterized, the association of mTORC1 inhibition with proteasome biogenesis and activity has not been fully elucidated yet. Proteasomes are long-lived cellular organelles. Their spatiotemporal rather than homeostatic regulation could be another adaptive cellular mechanism to respond to starvation. Here, we reviewed several published reports and the latest research from our group to examine the connection between mTORC1 and proteasome. We have also investigated and described the effect of mTORC1 inhibition on proteasome activity using purified proteasomes. Since mTORC1 inhibitors are currently evaluated as treatments for several human diseases, a better understanding of the link between mTORC1 activity and proteasome function is of utmost importance.

• Development and Reproduction
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• v.27 no.1
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• pp.39-46
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• 2023

Pumilio (Pum) is an RNA-binding protein and translational repressor important to diverse biological processes. In the Drosophila ovary, Pum is expressed in female germline stem cells (GSCs), wherein it acts as an intrinsic stem cell maintenance factor via repressing target mRNAs that are as yet mostly unknown. Pum recognizes the Pum binding sequence (PBS) in the mRNA 3'UTR through its C-terminus Puf domain. Translational repression is mediated through its N-terminal domain, but the molecular mechanism remains largely unknown. We previously showed that Bag-of-marbles, a critical differentiation-promoting factor of female GSCs, physically interacts with the N-terminus of Pum. We further showed that this interaction is critical to Bam inhibition of Pum repressive action in cultured cells, but the physiological relevance was not addressed. Here we design an in vivo GFP translational reporter bearing the PBS in its 3'UTR and show that GFP expression is reduced in cells wherein Pum is known to be active. Furthermore, we demonstrate in pum mutant ovary that this GFP repression requires Pum, and also that the sensor faithfully monitors Pum activity. Finally, we show that forced expression of Bam inhibits Pum-mediated repression, validating that Bam inhibits Pum activity in vivo.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.25 no.2
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• pp.174-183
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• 2015

Objectives: The objective of this study is the estimation of factors influencing airborne fiber concentrations by means of an observation survey of asbestos-containing materials in buildings. Methods: Forty-five samples were collected from four commercial buildings by NIOSH Method 7400 and classified according to current condition, potential activity, construction year, and operations and maintenance(O&M). Results: Airborne fiber concentrations by current condition(classified as good, fair and poor) were significantly different(p<0.05). Concentrations by potential activity were significantly different among groups(p<0.05), and those from the low activity group were higher than those from the middle activity group. Based on construction year, airborne fiber concentrations from the decade of the 1990's were higher than those from the 1960's. When O&M status was considered, airborne fiber concentrations from 1960's buildings were lower than those buildings not operated and maintained(p<0.01), because dust generation was influenced by O&M status. It was found that airborne fiber concentrations were related to current condition and potential activity via regression analysis, but the coefficient of determination was low. Also, correlation analysis showed that the higher the potential activity, the more current condition is worsened, but the relationship was not significant(r=-0.455, p>0.05). Conclusions: Airborne fiber concentrations in asbestos-containing buildings had weak relationships with current condition and potential activity.

• Korean Journal of Applied Biomechanics
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• v.16 no.1
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• pp.19-30
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• 2006

The purpose of this study was to examine the effect of foot orthotics on the overall comfort and muscle activity during running. The subjects were 10 members from the joggers' club which consisted of 2 women and 8 men. These individuals ran on the treadmill by 4.0m/s speed with and without the custom foot orthotics. The data concerning the overall comfort was collected by a questionairre that examined the overall comfort, heel cushioning, forefoot cushioning, medio-lateral control, arch height, heel cup fit, shoe heel width, forefoot width, and shoe length The MegaWin ver. 2.1(Mega Electronics lid, Ma. Finland) was used to gain electromyography signals of the muscle activity; Tibialis anterior, medial gastronemius, lateral gastronemius, vastus lateralis, vastus medialis, biceps femoris, and rectus femoris were measured. The results of the study were as follows. 1. During running the overall comfort was higher for the foot arthotic condition than the nonorthotic condition. Among the inquiries the overall comfort showed the biggest difference comparing the two conditions. and the shoe heel width showed the highest score for contort. 2 The muscle activity of the biceps femoris, and vastus lateralis in the stance period decreased. due to the foot orthotics. The muscle activity of the vastus medialis in the swing period also decreased and the muscle activity tibialis anterior in the stance and swing stance decreased as well During running, orthotics showed positive result in foot comfort. The foot comfort related to decreased stress, muscle activity, and foot arch strain. Overall comfort and the adequate decrease of muscle activity were associated with injury prevention and the best method to prevent injury semms to be the maintenance of foot comfort.

• Journal of Korean Society of Forest Science
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• v.86 no.1
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• pp.80-86
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• 1997

The objective of this study was to investigate how resistant poplar hybrid makes compensation to ozone stress. Growth, net assimilation rate and initial Rubisco activity were investigated. This study elucidates the physiological mechanisms associated with ozone sensitivity and resistance in 3 selected $F_2$ hybrids, a family originating from a cross between Populus trichocarpa${\times}$P. deltoides. Open-top chambers were used. Ozone concentrations varied from 90 to 115 ppb for 126 days, 6 to 9 hours in a day. This study tested the hypothesis that resistant poplar hybrid maintains the biomass production to ozone exposure via increased net assimilation rate and Rubisco activity. Growth, biomass, net assimilation rate and initial Rubisco activity were generally reduced by ozone treatment. In the tree parts, root under ozone stress was the most sensitive part. Reduced allocation of photosynthates to root growth might be due to increased respiratory demands for maintenance and repair of aboveground tissue damaged by ozone stress. Maintenance or increases remaining leaves in photosynthetic rates and Rubisco activity in resistant clone in response to ozone treatment were the results of biological compensation to ozone stress.

• Journal of Integrative Natural Science
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• v.9 no.2
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• pp.144-151
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• 2016

The purpose of this study is to investigate the emotion effects on academic achievement for university students. The results are as follows. Resulting on the each emotions difference by the statistical variables, anxiety scores by gender showed a significant difference in the p<.01 level(F=7.685). The males anxiety(2.478, standard deviation: 0.180) had significantly lower scores than females(3.076, standard deviation: 0.168). But fear, anger, activity, and sociability scores were not significantly different respectively between male and female students. To see the emotions effect of academic achievement, the analysis method of the linear regression line was used. As the result, anxiety, fear, anger, activity, and sociability did not significantly influence academic achievement. And so unlike previous methods, the analysis method of the quadratic regression curve was used. As the result, anxiety, fear, anger, activity, and sociability showed did significantly influence academic achievement respectively within 5% of statistical significance level, to more than F=3.06. Therefore, the values on academic achievement of the each anxiety, fear, anger, activity, and sociability showed a quadratic regression curve. That is, [Academic achievement]=$-0.9685{\times}[Anxiety]^2+5.1342{\times}[Anxiety]+8.2679$,[Academic achievement]=$-1.0638{\times}[Fear]^2+5.5694{\times}[Fear]+7.5635$,[Academic achievement]=$-1.3497{\times}[Anger]^2+9.1284{\times}[Anger]+0.6720$,[Academic achievement]=$-1.0589{\times}[Activity]^2+7.4386{\times}[Activity]+1.8272$,[Academic achievement]=$-1.6830{\times}[Sociability]^2+11.2325{\times}[Sociability]-3.8258$. Therefore, we were able to determine the following conclusions. First, we were able to predict the degree of academic achievement by the each emotions scale. Second, when the each emotion scores of students was a moderate, the academic achievement was most excellent. So, in order for the students to become higher academic achievement, the maintenance of medium degree of the each emotions scores is required.

• The Korean Journal of Physiology and Pharmacology
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• v.24 no.1
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• pp.1-10
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• 2020

Autophagy is a highly conserved intracellular degradation and energy-recycling mechanism that contributes to the maintenance of cellular homeostasis. Extensive researches over the past decades have defined the role of autophagy innate immune cells. In this review, we describe the current state of knowledge regarding the role of autophagy in neutrophil biology and a picture of molecular mechanism underlying autophagy in neutrophils. Neutrophils are professional phagocytes that comprise the first line of defense against pathogen. Autophagy machineries are highly conserved in neutrophils. Autophagy is not only involved in generalized function of neutrophils such as differentiation in bone marrow but also plays crucial role effector functions of neutrophils such as granule formation, degranulation, neutrophil extracellular traps release, cytokine production, bactericidal activity and controlling inflammation. This review outlines the current understanding of autophagy in neutrophils and provides insight towards identification of novel therapeutics targeting autophagy in neutrophils.