• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.20 no.5
• /
• pp.599-604
• /
• 2019

This study examined how the characteristics of smartphone affect the functional performance of smartphones. In particular, this study focused on an understanding of the correlation between smartphone functional factors and usage habits. Functionality is defined as 11 kinds of functional elements. The characteristics of the smartphones were defined as the hardware characteristics and the user habits characteristics. Eighty subjects were organized to collect actual data by the smartphone function. The actual time required to perform each function was measured and observed five times for each functional element. Regression analysis was performed using Minitab ver.14 by classifying the measured values of the functional elements as dependent variables, the hardware characteristics collected through the questionnaire, and the user's usage habits as 12 independent variables. Overall, it is difficult to conclude that demographic and hardware characteristics of smartphone users have a significant effect on the performance. On the other hand, the variables related to smartphone usage habits have had a great impact on the performance of smartphone tasks, and as a result, the task execution time has increased. In simple input variables or viewing variables, the effects on usability was relatively small, but in all active variables, the execution time increased 10% - 30% in all tasks except for phone calls, seeking phone numbers, and dictionary search. Thus far, if the smartphone user interface has been provided uniformly in a large and simple manner, users with various usage habits can be utilized even if the input method and task processing method are more complicated and various interface types are provided.

• Journal of Life Science
• /
• v.29 no.5
• /
• pp.530-536
• /
• 2019

Glioblastoma (GBM) is the most incurable brain cancer derived from the transformed glial cells. Standard anti-GBM treatment, including surgery and chemoradiotherapy, does not ensure good prognosis for the patients with GBM, because successful therapy is often impeded by presence of glioma stem cells (GSCs). GSCs, which is generally divided into proneural (PN) and mesenchymal (MES) subtype, are understood as subpopulation of cancer cells responsible for GBM initiation, progression and recurrence after standard treatments. In the present study, we demonstrate that PN subtype GSCs differentially transit to MES subtype GSCs by specific cytokines. The expression of CD44, a marker of MES subtype GSCs, was observed when GSC11 PN subtype GSCs were exposed to tumor necrosis factor alpha ($TNF-{\alpha}$) cytokine and GSC23 PN subtype GSCs were treated to transforming growth factor beta 1 ($TGF-{\beta}1$) cytokine. Ivy glioblastoma atlas project (Ivy GAP) bioinformatics database showed that $TNF-{\alpha}$ and $TGF-{\beta}1$ were highly expressed in necrotic region and perivascular region, respectively. In addition, $TNF-{\alpha}$ signaling was relatively upregulated in necrotic region, while $TGF-{\beta}$ signaling was increased in perivascular region. Taken together, our observations suggest that MES subtype GSCs can be derived from various PN subtype GSCs by multimodal cytokine stimuli provided by neighboring tumor microenvironment.

• Journal of Cadastre & Land InformatiX
• /
• v.51 no.1
• /
• pp.111-124
• /
• 2021

Recently, Interest in the restoration and 3D reconstruction of cultural properties due to the fire of Notre Dame Cathedral on April 15, 2019 has been focused once again after the 2008 Sungnyemun fire incident in South Korea. In particular, research to restore and reconstruct the actual measurement of cultural properties using LiDAR(Light Detection and ranging) and conventional surveying, which were previously used, using various 3D reconstruction technologies, is being actively conducted. This study acquires data using unmanned aerial imagery of UAV(Unmanned Aerial Vehicle), which has recently established itself as a core technology in the era of the 4th industrial revolution, and the existing CRP(Closed Range Photogrammetry) and terrestrial LiDAR scanning for the Recumbent Buddha of Unju Temple. Then, the 3D reconstruction was performed with three fusion models based on SfM(Structure-from-Motion), and the reproducibility and accuracy of the models were compared and analyzed. In addition, using the best fusion model among the three models, the relationship with the Polar Star(Polaris) was confirmed based on the real world coordinates of the Recumbent Buddha, which contains the astronomical history of Buddhism in the early 11th century Goryeo Dynasty. Through this study, not only the simple external 3D reconstruction of cultural properties, but also the method of reconstructing the historical evidence according to the type and shape of the cultural properties was sought by confirming the historical evidence of the cultural properties in terms of spatial information.

• International Area Studies Review
• /
• v.21 no.2
• /
• pp.97-120
• /
• 2017

This study attempted to examine how Chinese consumers' brand authenticity of Korean cosmetic brands are related to brand loyalty through brand aura. In other words, this study observed how Chinese consumers' brand authenticity, which includes product, employee and corporate authenticity related to Korean cosmetic brands, influence on the consumers' brand loyalty through brand aura. To this end, we surveyed Chinese consumers visiting Korean cosmetic brand shops in department stores, discount stores and large shopping malls in Beijing, Shanghai, Guangzhou in China. A total of 400 surveys were used in the empirical analysis. The results of empirical analysis confirmed that product, employee, and corporate authenticity of Chinese consumers have for Korean cosmetic brands positively influenced on brand aura. Furthermore, results showed that Chinese consumers' brand aura of Korean cosmetic brands had a positive effect on brand loyalty. The results of this study provide implications to help Korean cosmetic companies gain a competitive edge in the Chinese cosmetic market by understanding Chinese consumers' authenticity of their brands and building brand images and using differentiated marketing strategies that can induce brand aura.

• Conservation Science in Museum
• /
• v.24
• /
• pp.55-74
• /
• 2020

The Sacred Bell of Great King Seongdeok is required digital precision recording of conservation conditions because of corrosion and partial abrasion of its patterns and inscriptions. Therefore, this study performed digital documentation of the bell using four types of scanning and unmanned aerial vehicle (UAV) photogrammetry technologies, and performed the various shape analyses through image processing. The modeling results of terrestrial laser scanning and UAV photogrammetry were merged and utilized as basic material for monitoring earthquake-induced structural deformation because these techniques can construct mutual spatial relationships between the bell and its tower. Additionally, precision scanning at a resolution four to nine times higher than that of the previous study provided highly valuable information, making it possible to visualize the patterns and inscriptions of the bell. Moreover, they are well-suited as basic data for identifying surface conservation conditions. To actively apply three-dimensional scanning results to the conservation of the original bell, the time and position of any changes in shape need to be established by further scans in the short-term. If no change in shape is detected by short-term monitoring, the monitoring should continue in medium- and long-term intervals.

• Journal of the Korean Recycled Construction Resources Institute
• /
• v.9 no.1
• /
• pp.75-84
• /
• 2021

In this study, the correlation between cement quality(chemical composition, mineral composition, and compressive strength) and amount of waste alternative fuels used in the cement manufacturing process and was investigated. Cement manufacturing facility using coal, soft plastics(plastics that are easily scattered by wind power, such as vinyls), hard plastics(plastics that do not contain foreign substances, waste rubber, PP, etc.) and reclaimed oil was analised. Data was collected for 3 years from 2017 to 2019 and let the amount of fuels used as an independent variable and cement quality data as a dependent variable. As a result, depending on the type and quality of the alternative fuel has not a significant effect on the chemical composition(Cl and LSF) and mineral composition(f-CaO, C3S contents). Contrary to the concern that the compressive strength of cement would decrease, there was a significant positive correlation between amount of alternative fuel used and cement compressive strength.

• Korean Chemical Engineering Research
• /
• v.60 no.2
• /
• pp.217-222
• /
• 2022

It is very important to analyze the OCV change behavior during the open circuit potential holding (OCV holding) process, which accelerates the evaluation of the electrochemical durability of the PEMFC membrane. In this study, an empirical formula using the experimental data of three MEAs with different durability was created and compared. The durability evaluation time of the reinforced membrane MEA without radical scavenger inside the membrane was 383 h, and the durability evaluation time of the reinforced membrane MEA with radical scavenger inside the membrane was 1,000 and 1,650 h, respectively. The degradation of the membrane was divided into the reversible degradation that can be recovered by activation and the irreversible degradation that is not recovered. The irreversible degradation of the membrane was indicated by an increase in hydrogen permeability, and the change in hydrogen permeability was similar to the irreversible degradation constant c of all three MEAs. The initiation of irreversible deterioration without recovery is indicated by an increase in hydrogen permeability, and the OCV is not recovered due to an increase in hydrogen permeability, so the slope of the OCV recovery line (ORL) decreases, which can be confirmed by an increase in the constant c value of the empirical formula.

• Clean Technology
• /
• v.28 no.1
• /
• pp.9-17
• /
• 2022

Electrochemical carbon dioxide (CO₂) reduction technology, one of the promising solutions for climate change, can convert CO₂, a representative greenhouse gas (GHG), into valuable base chemicals using electric energy. In particular, carbon monoxide (CO), among various candidate products, is attracting much attention from both academia and industry because of its high Faraday efficiency, promising economic feasibility, and relatively large market size. Although numerous previous studies have recently analyzed the GHG reduction potential of this technology, the assumptions made and inventory data used are neither consistent nor transparent. In this study, a comparative life cycle assessment was carried out to analyze the potential for reducing GHG emissions in the electrochemical CO production process in a more transparent way. By defining three different system boundaries, the global warming impact was compared with that of a fossil fuel-based CO production process. The results confirmed that the emission factor of electric energy supplied to CO₂-electrolyzers should be much lower than that of the current national power generation sector in order to mitigate GHG emissions by replacing conventional CO production with electrochemical CO production. Also, it is important to disclose transparently inventory data of the conventional CO production process for a more reliable analysis of GHG reduction potential.

• Journal of the Korea Convergence Society
• /
• v.13 no.3
• /
• pp.125-131
• /
• 2022

Recently, the prevalence of remotely managed patient care systems in medical institutions is increasing due to COVID-19. In particular, in the case of fluid monitoring, hospitals are considering introducing it as a system that can reduce patient safety and nurses' work. There are two products under development: a load cell method that measures weight and a method that detects drops of sap by infrared sensing. Although each product has differences in operation principle, sensor type, size, usage, and price, medical institutions are highly interested in the accuracy of the data obtained.In this study, two prototypes with different sensor methods were manufactured and the total amount of infusion per hour was measured to test the accuracy, which is the core of the infusion monitoring device. In addition, when there was an external movement, the change in the measured value of the sap was tested to evaluate the accuracy according to the measurement method. As a result of the experiment, there was a difference of less than 5% in the measurement value error of the two devices, and the load cell method showed a difference in the low-capacity measurement value and the infrared method in the high-capacity measurement value. As a result of this experiment, there was little difference in accuracy according to the sensor method of the infusion monitoring device, and it is considered that there is no problem in accuracy when used in a medical institution.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
• /
• v.15 no.2
• /
• pp.103-108
• /
• 2022

Various studies have been conducted on cloud observation using all-sky images acquired with a wide-angle camera system since the early 21st century, but it is judged that an automatic observation system that can completely replace the eye observation has not been obtained. In this study, to verify the quantification of cloud observation, which is the final step of the algorithm proposed to automate the observation, the cloud distribution of the all-sky image and the corrected image were compared and analyzed. The reason is that clouds are formed at a certain height depending on the type, but like the retina image, the center of the lens is enlarged and the edges are reduced, but the effect of human learning ability and spatial awareness on cloud observation is unknown. As a result of this study, the average cloud observation error of the all-sky image and the corrected image was 1.23%. Therefore, when compared with the eye observation in the decile, the error due to correction is 1.23% of the observed amount, which is very less than the allowable error of the eye observation, and it does not include human error, so it is possible to collect accurately quantified data. Since the change in cloudiness due to the correction is insignificant, it was confirmed that accurate observations can be obtained even by omitting the unnecessary correction step and observing the cloudiness in the pre-correction image.