• Korean Journal of Remote Sensing
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• v.39 no.6_2
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• pp.1615-1633
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• 2023

Sargassum horneri is one of the floating algae in the sea, which breeds in large quantities in the Yellow Sea and East China Sea and then flows into the coast of Republic of Korea, causing various problems such as destroying the environment and damaging fish farms. In order to effectively prevent damage and preserve the coastal environment, the development of Sargassum horneri detection algorithms using satellite-based remote sensing technology has been actively developed. However, incorrect detection information causes an increase in the moving distance of ships collecting Sargassum horneri and confusion in the response of related local governments or institutions,so it is very important to minimize false detections when producing Sargassum horneri spatial information. This study applied technology to automatically remove false detection results using the GOCI-II-based Sargassum horneri detection algorithm of the National Ocean Satellite Center (NOSC) of the Korea Hydrographic and Oceanography Agency (KHOA). Based on the results of analyzing the causes of major false detection results, it includes a process of removing linear and sporadic false detections and green algae that occurs in large quantities along the coast of China in spring and summer by considering them as false detections. The technology to automatically remove false detection was applied to the dates when Sargassum horneri occurred from February 24 to June 25, 2022. Visual assessment results were generated using mid-resolution satellite images, qualitative and quantitative evaluations were performed. Linear false detection results were completely removed, and most of the sporadic and green algae false detection results that affected the distribution were removed. Even after the automatic false detection removal process, it was possible to confirm the distribution area of Sargassum horneri compared to the visual assessment results, and the accuracy and precision calculated using the binary classification model averaged 97.73% and 95.4%, respectively. Recall value was very low at 29.03%, which is presumed to be due to the effect of Sargassum horneri movement due to the observation time discrepancy between GOCI-II and mid-resolution satellite images, differences in spatial resolution, location deviation by orthocorrection, and cloud masking. The results of this study's removal of false detections of Sargassum horneri can determine the spatial distribution status in near real-time, but there are limitations in accurately estimating biomass. Therefore, continuous research on upgrading the Sargassum horneri monitoring system must be conducted to use it as data for establishing future Sargassum horneri response plans.

• Journal of Venture Innovation
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• v.4 no.3
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• pp.125-139
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• 2021

As the 4th industrial revolution progresses, new technologies and services are being born, growing, and maturing. Now, beyond the mobile era, the metaverse is being discussed as a new paradigm. Therefore, in this study, in preparation for the metaverse era, we tried to analyze what factors have an important influence when consumers want to use new technologies. In particular, the research was conducted focusing on how the context in which consumers use the technology changes depending on whether they are B2C or B2B. For this, augmented reality (AR) was selected in the B2C context by linking the research subject with the metaverse era, and the smart factory was selected in the B2B context. The research model for the analysis was established by deriving and setting common influence variables by reflecting the characteristics of the research target technology based on the modified extended unified theory of acceptance and use of technology. A survey was conducted for empirical analysis, and 150 AR and 150 smart factory subjects were analyzed. The empirical study results are as follows. The relationship between performance expectancy and intention to use, technology readiness and intention to use was found to have a significant positive (+) effect on both AR and smart factory. On the other hand, it was found that effort expectancy, social influence, and trust had a positive (+) effect on intention to use only in AR. Only in smart factory, facilitating conditions had a significant positive (+) effect on intention to use. It was also found that the perceived risk had a significant negative (-) effect on the intention to use only in the smart factory. The results of this study are academically significant in that we empirically test that influencing factors of technology use varies depending on the context in which it is used by consumers. In practice, it provided an implication of what to focus on first is being implemented.

• Journal of Venture Innovation
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• v.5 no.1
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• pp.19-37
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• 2022

The purpose of this study was to find out what could be the cause of increasing the re-use intention for the continuous management of customers in terms of finding a strategic plan for the survival of Medium Sized Hospital To this end, a hypothesis for the direct effect verifying the structural relationship, a hypothesis for the mediating effect of attachment, and a hypothesis for the moderating effect on the hospital image were presented. The survey analysis results for customers who experienced the services of 5 Medium Sized Hospital in Gyeonggi-do were as follows. First, The results of analysis of the effect of Medium Sized Hospital customers' perceived value on reuse intention are as follows. all sub-factors of perceived value did not have a significant effect on reuse intention. This is significant in that it shows that the change occurred due to the involvement of attachment. Second, the results of examining the mediating effect of attachment in the relationship between the perceived value of small and medium hospital customers and their intention to reuse are as follows. Attachment to doctor's competency significantly mediated the relationship between quality value and reuse intention, emotional value and reuse intention, and social value and reuse intention. Significantly mediated the relationship between the provinces and the relationship between the price value and the intention to reuse. Third, hospital image significantly adjusted the relationship between quality value and medical technology competency. Based on the above results, it is necessary to establish a strategy of value perceived by customers as a strategy to increase the reuse intention of small and medium hospital customers. Therefore, the strategic goal setting of this value should be 'promoting attachment', and since the hospital image adjusts the perceived value and attachment of small and medium hospital customers, it is an image strategy that allows customers to appreciate their attachment to doctors and medical technology more highly. will have to establish.

• Korean Journal of Remote Sensing
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• v.39 no.5_4
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• pp.1097-1109
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• 2023

Urban is an area where small-scale changes to individual buildings occur frequently. An existing urban building database requires periodic updating to increase its usability. However, there are limitations in data collection for building changes over a wide urban. In this study, we check the possibility of detecting building changes and updating a building database by using satellite images that can capture a wide urban region by a single image. For this purpose, building areas in a satellite image are first extracted by projecting 3D coordinates of building corners available in a building database onto the image. Building areas are then divided into roof and facade areas. By comparing textures of the roof areas projected, building changes such as height change or building removal can be detected. New height values are estimated by adjusting building heights until projected roofs align to actual roofs observed in the image. If the projected image appeared in the image while no building is observed, it corresponds to a demolished building. By checking buildings in the original image whose roofs and facades areas are not projected, new buildings are identified. Based on these results, the building database is updated by the three categories of height update, building deletion, or new building creation. This method was tested with a KOMPSAT-3A image over Incheon Metropolitan City and Incheon building database available in public. Building change detection and building database update was carried out. Updated building corners were then projected to another KOMPSAT-3 image. It was confirmed that building areas projected by updated building information agreed with actual buildings in the image very well. Through this study, the possibility of semi-automatic building change detection and building database update based on single satellite image was confirmed. In the future, follow-up research is needed on technology to enhance computational automation of the proposed method.

• Korean Journal of Remote Sensing
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• v.39 no.5_4
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• pp.1135-1144
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• 2023

Many agricultural reservoirs in South Korea, constructed before 1970, have become aging facilities. The majority of small-scale reservoirs lack measurement systems to ascertain basic specifications and water levels, classifying them as unmeasured reservoirs. Furthermore, continuous sedimentation within the reservoirs and industrial development-induced water quality deterioration lead to reduced water supply capacity and changes in reservoir morphology. This study utilized Light Detection And Ranging (LiDAR) sensors, which provide elevation information and allow for the characterization of surface features, to construct high-resolution Digital Surface Model (DSM) and Digital Elevation Model (DEM) data of reservoir facilities. Additionally, bathymetric measurements based on multibeam echosounders were conducted to propose an updated approach for determining reservoir capacity. Drone-based LiDAR was employed to generate DSM and DEM data with a spatial resolution of 50 cm, enabling the display of elevations of hydraulic structures, such as embankments, spillways, and intake channels. Furthermore, using drone-based hyperspectral imagery, Normalized Difference Vegetation Index (NDVI) and Normalized Difference Water Index (NDWI) were calculated to detect water bodies and verify differences from existing reservoir boundaries. The constructed high-resolution DEM data were integrated with bathymetric measurements to create underwater contour maps, which were used to generate a Triangulated Irregular Network (TIN). The TIN was utilized to calculate the inundation area and volume of the reservoir, yielding results highly consistent with basic specifications. Considering areas that were not surveyed due to underwater vegetation, it is anticipated that this data will be valuable for future updates of reservoir capacity information.

• Korean Journal of Poultry Science
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• v.50 no.4
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• pp.303-310
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• 2023

The current study was conducted to compare the effect of crossbred on the body weight and laying performance of Korean native chicken from hatch to week 40. A total of 873 one-day-old chicks were divided into twelve crossbreds (i.e., CFCK, CFYC, CFYD, CKCF, CKYC, CKYD, YCYD, YCCF, YCCK, YDCF, YDCK, and YDYC) and commercial layer (Hy-Line Brown) were obtained as a counterpart in the study. All the birds are raised in battery cages (76 × 61 × 46 cm³) and then raised until 14 weeks and subsequently moved to layer battery cages (60 × 25 × 45 cm³) and raised until 16 weeks. The body weight and viability were measured biweekly from hatching to week 16. The week of 16, body weight range was about 1,010.24 to 1,411.77 g. The body weight of specific crossbreeds (i.e., CKCF, YCYD, and YDYC) was found to be comparable to that of Hy-Line Brown). The viability hatch to week 14 range was about 55 to 100% and however week 14 to 16 range was 80 to 100%. The crossbred (i.e., CKCF) recorded superior (P<0.05) viability throughout the whole experiment period, even compared with Hy-Line Brown (100% vs 96%). Our results are indicating that crossbreds Korean native chicken including CKCF, and YDYC has the potential to enhance key features of laying hens during the growing phase like optimal body weight and higher viability.

• Korean Journal of Environment and Ecology
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• v.37 no.5
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• pp.367-391
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• 2023

This study was conducted for 10 years from 2012, which is a year before the forest road construction in Minjujisan, to 2022 to analyze annual changes in flora and vegetation before and after the forest road construction and to provide strategies for management. The plant communities in the research sites along the forest road showed the differentiation between slopes with Quercus mongolica community on the northwestern slope and Quercus variabilis and Larix kaempferi communities on the southwestern slope. A total of 212 taxa have increased for number 7 between before and after the construction from a total of 66 taxa (44 families, 59 genera, 51 species, 13 varieties, and 2 forma) in 2012 and 207 taxa (71 families, 153 genera, 176 species, 27 varieties, and 4 forma) in 2015 to 278 taxa (78 families, 172 genera, 242 species, 1 subspecies, 31 varieties, and 4 forma) in 2022. It is noteworthy that the vegetation cover and the introduction of new taxa had been expanded in the sites adjacent to the construction, which is likely caused by the significantly increased amount of light and the introduction of annual herbaceous and naturalized plants after the construction. The results of 10 years of current study reveal that the vegetation cover and the number of new taxa had rapidly increased in earlier years after the construction, slowly decreased later on, and finally formed a stable forest with the increase in the ratio of dominant species. The vegetation cover of the herbaceous layer immediately increased on the slopes along the forest road for a few years after the construction although it had continuously decreased while that of the shrub layer quickly increased. It was shown that on the hillslope the vegetation cover of tall- and low-tree layers increased whereas that of herbaceous and shrub layers rapidly decreased.

• Journal of Food Hygiene and Safety
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• v.38 no.5
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• pp.319-331
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• 2023

Aminoglycoside antibiotics, also known as aminoglycosides (AGs), are veterinary drugs effective against a wide range of gram-negative and gram-positive bacteria. Owing to their recent use in cultured meats, it has become essential to establish an analytical method for safety management. AGs are highly polar compounds, and ion-pair reagents (IPRs) are used to ensure component separation. Owing to the high possibility of potential mechanical problems resulting from IPR addition to the mobile phase, an analytical method in which IPRs are added directly to the vial was explored. In this study, methods for analyzing 10 AGs via liquid chromatography-tandem mass spectrometry (LC-MS/MS) with the addition of two IPRs were validated for selectivity, detection limit, quantitation limit, recovery, and precision. The detection limit was 0.0001-0.0038 mg/kg, the quantification limit was 0.004-0.011 mg/kg, and the linearity (R²) within the concentration range of 0.01-0.5 mg/kg was over 0.99. Recovery and precision (expressed as relative standard deviation) evaluated in the two matrices (beef and cell culture media) ranged from 70.7% to 120.6% and 0.2% to 24.7%, respectively. The validated AG analytical method was then applied to 15 meats prepared from chicken, beef, and pork, and 6 culture media and additives used in cultured meat. No AGs were detected in any of the 15 meats distributed in Korea; however, streptomycin and dihydrostreptomycin were detected at levels ranging from 695.85 to 1152.71 mg/kg and 6.35 to 11.11 mg/kg, respectively, in the culture media additives. The LC-MS/MS method coupled with direct addition of IPRs to the vial can provide useful basic data for AG analysis and safety evaluation of meats as well as culture media and additives for cultured meats.

• Korean Journal of Mineralogy and Petrology
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• v.36 no.4
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• pp.323-336
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• 2023

We investigated the nickel potential and genesis of ultramafic rocks in the Yugu area to secure nickel resources in South Korea. The Yugu ultramafic rocks, located in the southwest of the Gyeonggi Massif, are characterized by spinel peridotite and exhibit strong serpentinization along their boundaries. The serpentinization is observed as olivine transformed to antigorite and chrysotile, while pentlandite, the nickel sulfide mineral, altered into millerite and awaruite. Serpentine displays distinct foliation, aligning subparallel to the ultramafic rock boundaries and foliation of Yugu gneiss. This suggests that the uplift of ultramafic rocks resulted in hydrothermal infiltration likely sourced from the Yugu gneiss metamorphism. The Yugu ultramafic rocks are residues after 5~18% partial melting of abyssal peridotite. Enriched light rare earth elements and Eu imply secondary metasomatism. Geochemistry suggests a link between the formation of Yugu ultramafic rock and the Triassic collision of the North and South China continents. The nickel content is around 0.17~0.21%, mainly contained in olivine and serpentine. Hence, in addition to the mineral processing study on the sulfide minerals, focused studies on oxide minerals for enhanced nickel recovery within the Yugu ultramafic rock are strongly suggested.

• Korean Journal of Culture and Social Issue
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• v.15 no.1
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• pp.95-132
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• 2009

Can money buy happiness? If not, what are the factors that influence happiness? What makes people happy? What are the factors that influence happiness among Korean adults? How can we better explain factors that influence happiness? These are the research questions that led to the analyses of psychological, relational, financial resources that influence happiness. To examine differences in socio-economic status, adults and elderly from three different districts that vary wealth and income were interviewed in their own home. A total of 313 respondents (male=133, female=180) between the ages of 20 through 80 completed a questionnaire that contained background information, emotional support scale and happiness scale developed by the present researcher and resiliency of efficacy developed by Bandura(1995). The results are as follows. First, monthly income influence happiness to some extent, but when the variable was excluded from the path analysis, the goodness-of-fit did not change significantly. Although those who have more money can be happier, those without much money can also be happy. These results indicate that financial resource has limited influence on happiness. In addition, monthly income did influence self-efficacy of respondents indicating that those with more money were not necessarily more confident about themselves. Second, an important factor influencing happiness is the relational resource. Emotional support was the most powerful predictor of happiness, four to five times more important than monthly income. Third, self-efficacy influenced happiness. Those respondents with higher resiliency of efficacy had higher happiness scores and the influence was two times greater than monthly income. Moreover, self-efficacy played a mediating role between emotional support and happiness. Fourth, those respondents with higher occupational achievement reported higher happiness score and the influence was two times greater than monthly income. Fifth, success of children influenced happiness score and the influence was 1.5 times greater than monthly income. Sixth, education did not directly influence happiness, but had an indirect influence through self-efficacy and occupational achievement. Seventh, age was not related to self-efficacy and happiness.