• Journal of Korea Water Resources Association
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• v.54 no.11
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• pp.903-913
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• 2021

In the flood season, the measurement of the river discharge has many restrictions due to reasons such as budget, manpower, safety, convenience in measurement and so on. In particular, when heavy rain events occur due to typhoons, etc., it is difficult to measure the amount of flood due to the above problems. In order to improve this problem, in this study, a method was developed that can measure the river discharge in a flood season simply and safely in a short time with minimal manpower by combining the functions of a drone and a surface velocity doppler radar. To overcome the mechanical limitations of drones caused by weather issues such as wind and rainfall derived from the measurement of the river discharge using the conventional drone, we developed a drone with P56 grade dustproof and waterproof performance, stable flight capability at a wind speed of up to 36 km/h, and a payload weight of up to 10 kg. Further, to eliminate vibration which is the most important constraint factor in the measurement with a surface velocity doppler radar, a damper plate was developed as a device that combines a drone and a surface velocity Doppler radar. The velocity meter DSVM (Dron and Surface Veloctity Meter using doppler radar) that combines the flight equipment with the velocity meter was produced. The error of ±3.5% occurred as a result of measuring the river discharge using DSVM at the point of Geumsan-gun (Hwangpunggyo) located at Bonghwang stream (the first tributary stream of the Geum River). In addition, when calculating the mean velocity from the measured surface velocity, the measurement was performed using ADCP simultaneously to improve accuracy, and the mean velocity conversion factor (0.92) was calculated by comparing the mean velocity. In this study, the discharge measured by combining a drone and a surface velocity meter was compared with the discharge measured using ADCP and floats, so that the application and utility of DSVM was confirmed.

• Journal of the Korean Society of Radiology
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• v.16 no.1
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• pp.67-75
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• 2022

The aim of this study is to establish a new QC method that can simultaneously evaluate the resolution of the x/y plane and the z-axis by producing a phantom that can reflect exposure and reconstruction parameter of MDCT system. It was used with Aquilion ONE(Cannon Medical System, Otawara, Japan), and the examination was scanned using of 120 kV, 260 mA, and the D-FOV of 300 mm². It produced new SSP phantom modules in which two aluminum plates inclined at 45° to a vertical axis and a transverse axis to evaluate high contrast resolution of x/y plane and z axis. And it changed factors such as the algorithm, distance from gantry iso-center. All images were reconstructed in five steps from 0.6 mm to 10.0 mm slice thickness to measure resolution of x/y plane and z-axis. The image data measured FWHM and FWTM using Profile tool of Aquarius iNtusion Edition ver. 4.4.13 P6 software(Terarecon, California, USA), and analysed SPQI and signal intensity by ImageJ program(v1.53n, National Institutes of Health, USA). It decreased by 4.09~11.99%, 4.12~35.52%, and 4.70~37.64% in slice thickness of 2.5 mm, 5.0 mm, and 10.0 mm for evaluating the high contrast resolution of x/y plane according to distance from gantry iso-center. Therefore, the high contrast resolution of the x/y plane decreased when the distance from the iso-center increased or the slice thickness increased. Additionally, the slice thicknesses of 2.5 mm, 5.0 mm, and 10.0 mm with a high algorithm increased 74.83, 15.18 and 81.25%. The FWHM was almost constant on the measured SSP graph for evaluating the accuracy of slice thickness which represents the resolution of x/y plane and z-axis, but it was measured to be higher than the nominal slice thickness set by user. The FWHM and FWTM of z-axis with axial scan mode tended to increase significantly as the distance increased from gantry iso-center than the helical mode. Particularly, the thinner slice thickness that increased error range compare with the nominal slice thickness. The SPQI increased with thick slice thickness, and that was closer to 90% in the helical scan than the axial scan. In conclusion, by producing a phantom suitable for MDCT detectors and capable of quantitative resolution evaluation, it can be used as a specific method in the management of research quality and management of outdated equipment. Thus, it is expected to contribute greatly to the discrimination of lesions in the field of CT imaging.

• Trans-
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• v.12
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• pp.173-222
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• 2022

This thesis examines the 'universe' acceptance phenomenon, currently used as a content strategy in the K-pop field, from the perspective of K-pop audiences, and then attempts to identify their experience of acceptance and the meaning of the universe. For this, tweets related to the universe acceptance experience of Aespa, the group utilizing the universe as a content strategy the most actively, were collected, and this data was analyzed according to a phenomenological approach, an approach to explore the structure of personal experience and the essence of a phenomenon. As a result of analyzing using Moustakas' method, the semantic structure of the universe acceptance phenomenon of K-pop audiences was derived based on 21 thematic units. It was found that current K-pop audiences are experiencing active cultural consumption rather than unilateral or passive through acceptance of the universe. This means that K-pop audiences have the characteristics of active audiences that produce meaning, interact with other fans, and exert influence on outside of community. At the same time, these characteristics affect acceptance of the universe. Simultaneously, through active acceptance experience, it is found that K-pop audiences give a new meaning in the K-pop universe, as "marketing assets", "fandom community assets", and "K-pop industry expansion assets." Among them, the recognition of 'marketing assets' was reaffirmed as a basis for supporting related previous studies. In addition, it derived the new values of the universe in the K-pop field by discovering the meaning of "fandom's specific assets" and "assets of the K-pop industry for expansion". These meanings had not been found that previous studies from the producers' point of view. And then, for the purpose of expanding the value of the universe in the future, it was discussed the direction of the new meaning of the universe. Finally, this study is meaningful in that it revealed the semantic structure of the universe acceptance phenomenon and discovered a new meaning of the universe in the K-pop field. Additionally, it was intended to contribute to expanding the field of research by suggesting various follow-up studies from various perspectives.

• Journal of Korea Port Economic Association
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• v.38 no.3
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• pp.133-149
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• 2022

The Port logistics is a pivotal industry in strengthening competitiveness for countries and companies and plays an important role in accounting for the majority of Korea's import and export volume, so its importance among Korea's industries is truly enormous. The port, which plays such an important role, is simultaneously unloaded, transferred into the dock, and stored, and it can be said that it is composed of a very complex flow. In particular, port unloading is an environment in which port unloading workers cannot escape the risk of disasters as large cargoes and cranes for container transport move, and numerous disasters are hidden and lead to serious disasters. Through literature studies on the Serious Accident Penalty Act, this study investigated how the Serious Accident Penalty Act affected port unloading workers and whether there was a change in satisfaction with safety education according to the enforcement of the Serious Accident Penalty Act. Through this study, it was found that port unloading workers were more aware of safety than managers in cognitive, attitude, and experience factors. Since the port unloading manager is not put into the unloading work, the perception of safety was analyzed to be lower than that of workers. Since managers should educate workers on safe work and be alert to safety, it seems that port unloading managers will also need to change their perception of safety. The Act on the Punishment of Severe Disasters took effect on January 27, 22, and in the early stages of the enforcement of the law, many confusing and ambiguous parts are found for those in charge of performing practical tasks on the front line until the law is settled. It seems necessary to revise the Act on the Punishment of Severe Disasters for the purpose of clear standards for the law and no safety accidents in the field to prevent confusion in work. In addition, in order to derive more meaningful research results in the future, it is expected that research on the perception of disasters by workers and managers will be continuously needed by deepening literature research to find various factors and using investigation methods such as interviews.

• Journal of Internet Computing and Services
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• v.23 no.5
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• pp.145-154
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• 2022

Automatic Target Recognition (ATR) technology is emerging as a core technology of Future Combat Systems (FCS). Conventional ATR is performed based on IMINT (image information) collected from the SAR sensor, and various image-based deep learning models are used. However, with the development of IT and sensing technology, even though data/information related to ATR is expanding to HUMINT (human information) and SIGINT (signal information), ATR still contains image oriented IMINT data only is being used. In complex and diversified battlefield situations, it is difficult to guarantee high-level ATR accuracy and generalization performance with image data alone. Therefore, we propose a knowledge graph-based ATR method that can utilize image and text data simultaneously in this paper. The main idea of the knowledge graph and deep model-based ATR method is to convert the ATR image and text into graphs according to the characteristics of each data, align it to the knowledge graph, and connect the heterogeneous ATR data through the knowledge graph. In order to convert the ATR image into a graph, an object-tag graph consisting of object tags as nodes is generated from the image by using the pre-trained image object recognition model and the vocabulary of the knowledge graph. On the other hand, the ATR text uses the pre-trained language model, TF-IDF, co-occurrence word graph, and the vocabulary of knowledge graph to generate a word graph composed of nodes with key vocabulary for the ATR. The generated two types of graphs are connected to the knowledge graph using the entity alignment model for improvement of the ATR performance from images and texts. To prove the superiority of the proposed method, 227 documents from web documents and 61,714 RDF triples from dbpedia were collected, and comparison experiments were performed on precision, recall, and f1-score in a perspective of the entity alignment..

• Journal of Intelligence and Information Systems
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• v.28 no.2
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• pp.127-146
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• 2022

Recently, as word embedding has shown excellent performance in various tasks of deep learning-based natural language processing, researches on the advancement and application of word, sentence, and document embedding are being actively conducted. Among them, cross-language transfer, which enables semantic exchange between different languages, is growing simultaneously with the development of embedding models. Academia's interests in vector alignment are growing with the expectation that it can be applied to various embedding-based analysis. In particular, vector alignment is expected to be applied to mapping between specialized domains and generalized domains. In other words, it is expected that it will be possible to map the vocabulary of specialized fields such as R&D, medicine, and law into the space of the pre-trained language model learned with huge volume of general-purpose documents, or provide a clue for mapping vocabulary between mutually different specialized fields. However, since linear-based vector alignment which has been mainly studied in academia basically assumes statistical linearity, it tends to simplify the vector space. This essentially assumes that different types of vector spaces are geometrically similar, which yields a limitation that it causes inevitable distortion in the alignment process. To overcome this limitation, we propose a deep learning-based vector alignment methodology that effectively learns the nonlinearity of data. The proposed methodology consists of sequential learning of a skip-connected autoencoder and a regression model to align the specialized word embedding expressed in each space to the general embedding space. Finally, through the inference of the two trained models, the specialized vocabulary can be aligned in the general space. To verify the performance of the proposed methodology, an experiment was performed on a total of 77,578 documents in the field of 'health care' among national R&D tasks performed from 2011 to 2020. As a result, it was confirmed that the proposed methodology showed superior performance in terms of cosine similarity compared to the existing linear vector alignment.

• Journal of the Korean Society of Marine Environment & Safety
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• v.28 no.6
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• pp.1092-1099
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• 2022

Research on exhaust aftertreatment devices to reduce air pollutants and greenhouse gas emissions is being actively conducted. However, in the case of the particulate matters/nitrogen oxides (PM/NOx) simultaneous reduction device for ships, the problem of back pressure on the diesel engine and replacement of the filter carrier is occurring. In this study, for the optimal design of the integrated device that can simultaneously reduce PM/NOx, an appropriate standard was presented by studying the flow inside the device and change in back pressure through the inlet/outlet pressure. Ansys Fluent was used to apply porous media conditions to a diesel particulate filter (DPF) and selective catalytic reduction (SCR) by setting porosity to 30%, 40%, 50%, 60%, and 70%. In addition, the ef ect on back pressure was analyzed by applying the inlet velocity according to the engine load to 7.4 m/s, 10.3 m/s, 13.1 m/s, and 26.2 m/s as boundary conditions. As a result of a computational fluid dynamics analysis, the rate of change for back pressure by changing the inlet velocity was greater than when inlet temperature was changed, and the maximum rate of change was 27.4 mbar. This was evaluated as a suitable device for ships of 1800kW because the back pressure in all boundary conditions did not exceed the classification standard of 68mbar.

• Journal of Life Science
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• v.32 no.12
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• pp.929-937
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• 2022

To investigate the anti-inflammatory activity of the grains of sorghum, three Sorghum bicolor (L.) Moench variants (Hwanggeumchal, Huinchal, and Chal) being cultivated in Korea, the 80% ethanol (EtOH) extracts of individual sorghum grains were compared for their inhibitory activity against nitric oxide (NO) production in lipopolysaccharide (LPS)-stimulated RAW264.7 murine macrophage cell line. Among them, the EtOH extract of sorghum Hwanggeumchal grains could exert the highest inhibitory effect on the LPS-induced NO production. However, under these conditions, the viability of RAW264.7 cells was not affected. When the EtOH extract of sorghum Hwanggeumchal grains was sequentially fractionated with n-hexane, methylene chloride (MC), ethyl acetate (EtOAc), and n-butanol, the anti-NO production activity was predominantly detected in both MC and EtOAc fractions. In particular, treatment with the MC fraction reduced dose-dependently the expression levels of iNOS, COX-2 and pro-inflammatory cytokines (IL-1β, IL-6, and TNF-α) in LPS-stimulated RAW264.7 cells. Simultaneously, the MC fraction could prevent LPS-induced activating phosphorylation of p38 mitogen-activated protein kinase (MAPK), c-Jun N-terminal kinase (JNK) and extracellular signal-regulated kinase (ERK). HPLC analysis of the MC fraction showed gentisic acid and naringenin as the major phenolic components. Both gentisic acid and naringenin commonly exhibited a potent inhibitory activity against LPS-induced NO production in RAW264.7 cells. Together, these results provide the evidence of the inhibitory activity of Hwanggeumchal grains on LPS-induce inflammatory responses in RAW264.7 murine macrophage cells and also suggest that sorghum grains possess beneficial health effects which can be applicable in development of the grain-based functional foods.

• Journal of the Korean Orthopaedic Association
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• v.56 no.2
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• pp.134-141
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• 2021

Purpose: Patellar dislocations have a range of causes. This study examined the results of treatment aimed at balancing soft tissues around the patella. Materials and Methods: Thirty-two patellar dislocations in 28 patients (21 females and seven males) were examined. The mean patient age at the time of surgery was 11.5 years, and the mean follow-up period was 4.6 years. Dislocations were 19 chronic, six habitual, six congenital, and one acute. Soft tissue balancing surgery included lateral capsular release, medial capsular plication, and inferolateral transfer of the vastus medialis obliquus. Medial transfer of the patellar tendon, partial strip of the rectus femoris and patella tendon, and distal femoral osteotomy were also performed selectively. The preoperative Q angle, femoral anteversion angle, tibial external rotation angle, tibial tubercle-trochlear groove distance (TT-TG distance), mechanical femoral-tibial angle, and femoral trochlear dysplasia according to Dejour were measured, and the pre- and postoperative Lysholm-Tegner scores were used to analyze the clinical results. Results: The mean preoperative Q angle, TT-TG distance, femoral anteversion angle, tibial external rotation angle, mechanical femoraltibia angle, and Lysholm-Tegner score were 9.3°, 15.5 mm, 25.6°, 30.4°, 3.0°, and 75.8, respectively. Eleven patients had systemic ligament laxity with a Beighton score of five or more. Twenty-two patients had femoral trochlear dysplasia: four type A (3 patients), 16 type B (15 patients), one type C (1 patient), and four type D (3 patients). Of the 32 cases, 28 were corrected successfully by the first operation. Of four cases of postoperative subluxation, three were corrected by the second operation, and one of them was corrected after a third operation. The last patient is currently being followed-up. The mean Lysholm-Tegner score improved to 85.6 after the operation. Conclusion: Correcting all the causes of patella dislocation simultaneously is difficult. Nevertheless, satisfactory outcomes were obtained with soft tissue balancing surgery around the patella and a corrective osteotomy for an abnormal mechanical axis of the femur-tibia and torsion.

• Journal of Bio-Environment Control
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• v.31 no.3
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• pp.180-187
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• 2022

In order to select suitable light in a plant factory, electric energy use efficiency and light use efficiency should be considered simultaneously to consider operating costs as well as quantitative and functional aspects. The growth characteristics, electric energy use efficiency, light use efficiency by light intensity, LED ratio, and photoperiod conditions were compared together. Light intensity is 60, 130, 230, and 320 µmol·m^-2·s^-1 treatments, and light quality is the mixing ratio of red light and blue light 8:2, 6:4, 4:6, and 2:8 treatments. Photoperiod is 9, 12, 15, and 18 hours treatments based on the daytime. In the light intensity experiment, the growth rate increased as the light intensity increased, but there was no significant difference in the light use efficiency. When comparing the leaf fresh weight per power consumption, only the 320 µmol·m^-2·s^-1 treatment group showed significantly low efficiency, and there was no significant difference in the other treatments, so 230 µmol·m^-2·s^-1, which produced the most, was the most efficient. In the light quality experiment, the ratio of red light and blue light was measured to be high at the same time as the growth rate and light use efficiency in RB 8:2, and there was no significant difference in color difference and flavonoids content, so a Red:Blue ratio of 8:2 was the most suitable condition. In the photoperiod experiment, the longer the photoperiod, the higher the growth rate. However, there was no significant difference in the growth rate over 12 hours of daytime, so 12 hours considering the light consumption efficiency was a suitable condition. Based on the above results, LED light environmental conditions for perilla growth in plant factories were light intensity, light quality, and day length of 230 µmol·m^-2·s^-1 or more, 8:2, and 12 hours or more, respectively.