• Korean Journal of Remote Sensing
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• v.37 no.6_1
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• pp.1731-1738
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• 2021

The objective of this study was to extract individual trees and tree heights using UAV drone images. The study site was Gongju national university experiment forest, located in Yesan-gun, Chungcheongnam-do. The thinning intensity study sites consisted of 40% thinning, 20% thinning, 10% thinning and control. The image was filmed by using the "Mavic Pro 2" model of DJI company, and the altitude of the photo shoot was set at 80% of the overlay between 180m pictures. In order to prevent image distortion, a ground reference point was installed and the end lap and side lap were set to 80%. Tree heights were extracted using Digital Surface Model (DSM) and Digital Terrain Model (DTM), and individual trees were split and extracted using object-based analysis. As a result of individual tree extraction, thinning 40% stands showed the highest extraction rate of 109.1%, while thinning 20% showed 87.1%, thinning 10% showed 63.5%, and control sites showed 56.0% of accuracy. As a result of tree height extraction, thinning 40% showed 1.43m error compared with field survey data, while thinning 20% showed 1.73 m, thinning 10% showed 1.88 m, and control sites showed the largest error of 2.22 m.

• Environmental and Resource Economics Review
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• v.30 no.3
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• pp.395-433
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• 2021

This paper aims to examine the effects of homeownership and residential types on the economic values of urban green spaces. Green open spaces as public goods provide positive externalities that are comprised of pecuniary and technological externalities. Seoul, South Korea, is used as a case study using choice experiments, with split-sample online respondents of 1,000. The study results evidenced that the differentiation between the two types of externalities is imperative for equitable provisions and efficient management of various urban open spaces. There is a positively significant and substantial impact of homeownership for apartment dwellers, ceteris paribus, but not for house dwellers. For apartments, the efficiency loss can be reduced by increasing green spaces up to the critical point where the marginal cost is at equilibrium with tenants' marginal values. For non-apartment houses, it is not homeownership but the monthly household income that has a significant impact on the amenity value. In general, public benefits from green spaces are equivalent to 16% to 33% of the current residential prices on average for a view or access. Different residential types do not cause a significant impact on the access values. Residential profiles for green spaces were developed, together with tailor-made policy suggestions.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.42
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• pp.32.1-32.4
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• 2020

Background: Le Fort I osteotomy is a highly effective treatment for skeletal jaw deformities and is commonly performed. High Le Fort I osteotomy is a modified surgical procedure performed for improving the depression of the cheeks by setting the osteotomy higher than the conventional Le Fort I osteotomy. Developments in three-dimensional (3D) technology have popularized the use of 3D printers in various institutions, especially in orthognathic surgeries. In this study, we report a safe and inexpensive method of performing a high Le Fort I osteotomy using a novel 3D device and piezosurgery, which prevent tooth root injury without disturbing the operation field for patients with a short midface and long tooth roots. Results: A 17-year-old woman presented with facial asymmetry, mandibular protrusion, a short midface, and long tooth roots. We planned high Le Fort I osteotomy and bilateral sagittal split ramus osteotomy. Prevention of damage to the roots of the teeth and the infraorbital nerve and accurate determination of the posterior osteotomy line were crucial for clinical success. Le Fort I osteotomy using 3D devices has been reported previously but were particularly large in size for this case. Additionally, setting the fixing screw of the device was difficult, because of the risk of damage to the roots of the teeth. Therefore, a different surgical technique, other than the conventional Le Fort I osteotomy and 3D device, was required. The left and right parts of the 3D device were fabricated separately, to prevent any interference in the surgical field. Further, the 3D device was designed to accurately cover the bone surface from the piriform aperture to the infra-zygomatic crest with two fixation points (the anterior nasal spine and the piriform aperture), which ensured stabilization of the 3D device. The device is thin and does not interfere with the surgical field. Safe and accurate surgical performance is possible using this device and piezosurgery. The roots of the teeth and the infraorbital nerve were unharmed during the surgery. Conclusions: This device is considerably smaller than conventional devices and is a simple, low-cost, and efficient method for performing accurate high Le Fort I osteotomy.

• Animal Bioscience
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• v.34 no.6
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• pp.1078-1087
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• 2021

Objective: Skeletal muscle satellite cells (SMSCs) are significant for the growth, regeneration, and maintenance of skeletal muscle after birth. However, currently, few studies have been performed on the isolation, culture and inducing differentiation of goose muscle satellite cells. Previous studies have shown that C1q and tumor necrosis factor-related protein 3 (CTRP3) participated in the process of muscle growth and development, but its role in the goose skeletal muscle development is not yet clear. This study aimed to isolate, culture, and identify the goose SMSCs in vitro. Additionally, to explore the function of CTRP3 in goose SMSCs. Methods: Goose SMSCs were isolated using 0.25% trypsin from leg muscle (LM) of 15 to 20 day fertilized goose eggs. Cell differentiation was induced by transferring the cells to differentiation medium with 2% horse serum and 1% penicillin streptomycin. Immunofluorescence staining of Desmin and Pax7 was used to identify goose SMSCs. Quantitative realtime polymerase chain reaction and western blot were applied to explore developmental expression profile of CTRP3 in LM and the regulation of CTRP3 on myosin heavy chains (MyHC), myogenin (MyoG) expression and Notch signaling pathway related genes expression. Results: The goose SMSCs were successfully isolated and cultured. The expression of Pax7 and Desmin were observed in the isolated cells. The expression of CTRP3 decreased significantly during leg muscle development. Overexpression of CTRP3 could enhance the expression of two myogenic differentiation marker genes, MyHC and MyoG. But knockdown of CTRP3 suppressed their expression. Furthermore, CTRP3 could repress the mRNA level of Notch signaling pathway-related genes, notch receptor 1, notch receptor 2 and hairy/enhancer-of-split related with YRPW motif 1, which previously showed a negative regulation in myoblast differentiation. Conclusion: These findings provide a useful cell model for the future research on goose muscle development and suggest that CTRP3 may play an essential role in skeletal muscle growth of goose.

• Korean Journal of Breeding Science
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• v.42 no.5
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• pp.515-524
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• 2010

The amylose content of starch is a major factor in the texture of cooked cereal grains. Therefore, down-regulation of amylose synthesis is one of the alternative method to improve eating quality of rice. We developed transgenic rice plants designed to suppress granule-bound starch synthase I(GBSSI) gene using RNA interference(RNAi) technology. Transgenic plants with RNAi vector containing the 3'-UTR region of GBSSI showed a lower amylose content in rice endosperm than that of wild-type. The range of amylose content was 5.9~9.0% in the transgenic plants, whereas that of wild-type was 17.7~18.0%. Transgenic rices showed the decrease of short chain and the increase of long chain by analyzing chain length distribution of amylopectin in the endosperm. In the SEM micrographs, we found that compound starch granules in whole grains of the wild-type rice were readily split during fracturing, while the starch granules in RNAi-transgenic lines showed small voluminous, non-angular rounded bodies.

• Journal of Hospice and Palliative Care
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• v.22 no.3
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• pp.134-143
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• 2019

Purpose: This methodological study was conducted to test the reliability and validity of an instrument that measures attitudes of advance directives (ADs) among nurses. Methods: 1) Sixteen items related to attitudes in the English version of the Knowledge, Attitudinal, and Experiential Survey on Advance Directives (KAESAD) were forward/backward translated into Korean. 2) The content was validated by an expert panel (three nursing professors and eight hospice nursing specialists). 3) The preliminary 12 items were selected as a tool to assess the Korean version of Nurses' Attitudes towards Advance Directives (NAAD-K). 4) The instrument was validated by a survey (n=216). 5) It was confirmed to use the 12 items for the final version of the instrument. Results: NAAD-K was shown to be valid in terms of factors, items and content. The three factors extracted from the factor analysis were named as follows: Caring for patients with an AD (factor 1), nurses' role in informing patients (factor 2) and patient right (factor 3). The three factors explained total variance 57.796%. Factor loadings of the 12 items ranged from 0.47 to 0.93. For the 12 items, Cronbach's alpha was 0.81, and Guttman split-half coefficient was 0.78. Conclusion: This instrument was identified to be applicable with satisfactory reliability and validity for further use in measuring nurses' attitudes towards ADs in hospice and palliative care.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.23 no.6
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• pp.719-725
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• 2019

We propose a 2.4-GHz CMOS power amplifier (PA) with a bypass structure to improve the power-added efficiency (PAE) in the low-power region. The primary winding of the output transformer is split into two parts. One of the primary windings is connected to the output of the power stage for high-power mode. The other primary winding is connected to the output of the driver stage for low-power mode. Operation of the high power mode is similar to conventional PAs. On the other hand, the output power of the driver stage becomes the output power of the overall PA in the low power mode. Owing to a turning-off of the power stage, the power consumption is decreased in low-power mode. We designed the CMOS PA using a 180-nm RFCMOS process. The measured maximum output power is 27.78 dBm with a PAE of 20.5%. At a measured output power of 16 dBm, the PAE is improved from 2.5% to 12.7%.

• Anxiety and mood
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• v.15 no.1
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• pp.53-60
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• 2019

Objective : GRIT is a non-cognitive trait which is defined as perseverance and passion for long-term goals. It predicts success, performance and thedifference from other traits. The purpose of this study was to examine the reliability and validity of the Korean version of the GRIT scale. Methods : A total of 92 patients were enrolled in the study. All patients received psychiatric assessment including Clinical Useful Depression Outcome Scale (CUDOS), Clinical Useful Anxiety Outcome Scale (CUXOS), Patient Health Questionnaire (PHQ-15), Connor-Davidson Resilience Scale (CDRS), Brief Resilience Scale (BRS), and GRIT as well as demographic assessment. Cronbach's alpha coefficient of total GRIT score and the split-half reliability of each item was calculated to assess test reliability. Exploratory and confirmatory factor analyses were performed to select the best fitting model and assess construct validity. Finally, a correlation analysis was performed to check convergent and discriminant validity. Results : Cronbach's alpha coefficient for GRIT was found to be 0.85 and all Cronbach's alpha were more than 0.8 even in cases where all items were deleted. We found 3 appropriate factor models in exploratory factor analysis, compared them with 3 models and chose the 2-factor model as the most suitable based on the best fit test. Finally, correlation of the GRIT with CUDOS, CUXOS, PHQ-15, CDRS and BRS were statistically significant (all p<0.01), with relatively low correlation coefficient. Conclusion : This study indicates that the Korean version of GRIT is a reliable and valid instrument for investigating individual power of passion and perseverance.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.18 no.2
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• pp.44-57
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• 2019

It is crucial to understand how people make decisions on mode choice and to accurately predict their behaviors in transportation planning. One of avenues for advancing modeling is, in particular, taking into account for taste heterogeneity in modeling that can incorporate different decision-making processes across group. In this study, we hypothesize that how people make decisions on mode choice would differ by destination in that land use characteristics are heterogeneous by zone even if zones are all in the same area. To this end, we apply Latent Class Modeling (LCM) to commute trips in Seoul by using 2010 household travel diary survey, investigate types of latent classes with the aid of characteristics of destination, and analyze how those classes differently response to factors. The LCM identifies two classes: in the first one, modal split of auto and public transit (bus and metro) is almost half-and-half and the trip destinations are characterized by relatively more residence facilities and less business/commercial facilities; in the second one, public transit has a notably high share and trip destinations are characterized by relatively more business/commercial facilities. In addition, it turns out that demographic and socio-economic variables affect mode choice differently by class.

• 한국노년학
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• v.32 no.4
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• pp.1163-1180
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• 2012

The main purpose of this study is to figure out the spending tendency of elderly consumers for their grandchildren. To this end, a detailed survey was carried out for two months from October 1 to November 30, 2011. The respondents consist of 461 elderly consumers over 60s who have grandchildren in elementary grades. Among the gathered data, relevant information was sorted out, coded, and then turned into statistical figures through SPSS 18.0 program. The outcome of this research is explained in the following three respects. First of all, based upon factor and cluster analysis, the role of grandparents has been divided into three categories, which are a babysitter, a friend and a visitor. Depending on their role, the surveyed elderly have been split into three groups-'Friend Group', 'Formal Visitor Group', 'Attached Group'. Second, to give you an overview of the consumption trend of the three groups, this study has reviewed the expenditure items, spending amount and consumption patterns, and made a list of products and services they purchased for the past one year for their grandchildren. Third, given the probability of wealth transfer to the next generation, there is a compelling need to figure out the purchase pattern of financial products. The elderly have been categorized into those with bank deposits only and those with a mixture of bank deposits and other financial products (insurance, fund, stocks, gold, dollar etc.).