• Journal of Korea Society of Industrial Information Systems
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• v.27 no.4
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• pp.37-45
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• 2022

In this paper, a multi agent-multi task assignment problem, which is a representative problem of combinatorial optimization, is presented. The objective of the problem is to determine the coordinated agent-task assignment that maximizes the sum of the achievement rates of each task. The achievement rate is represented as a concave down increasing function according to the number of agents assigned to the task. The problem is expressed as an NP-hard problem with a non-linear objective function. In this paper, to solve the assignment problem, we propose a hybrid cross-entropy algorithm as an effective and efficient solution methodology. In fact, the general cross-entropy algorithm might have drawbacks (e.g., slow update of parameters and premature convergence) according to problem situations. Compared to the general cross-entropy algorithm, the proposed method is designed to be less likely to have the two drawbacks. We show that the performances of the proposed methods are better than those of the general cross-entropy algorithm through numerical experiments.

• International Journal of Industrial Entomology and Biomaterials
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• v.45 no.2
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• pp.115-125
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• 2022

In this study, we investigated the developmental characteristics and genetic diversity of seven populations of two-spotted crickets (Gryllus bimaculatus De Geer, 1773 (Orthoptera: Gryllidae)) raised in South Korea. Regarding the developmental characteristics of the species, we observed no statistically significant difference in the weight of the nymphs in the six populations we tested. After molting, although weight differences were observed between the populations in each stage of the developmental period, the average weight for each developmental stage was constant. We also analyzed mitochondrial COI gene sequences (DNA barcoding region) of the reared crickets collected from five insect farms and two national insect rearing facilities and the resultant sequences were analyzed together with the 12 sequences from foreign countries specimens obtained from public data. We detected six haplotypes from 111 specimens, indicating a low intraspecific genetic distance (~1.8%). The most dominant haplotype was overwhelmingly haplotype 1, which was found in all South Korean specimens and four specimens from China, Indonesia, and Germany. These findings indicate that the low genetic diversity of South Korean specimens can be explained by the fact that the G. bimaculatus population imported for feed from Japan in the early 2000s became a maternal group that spread throughout cricket farms in South Korea. In order to breed healthy cricket strains, it is necessary to increase genetic diversity by importing them from other countries through appropriate quarantine procedures.

• Journal of Society of Preventive Korean Medicine
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• v.26 no.3
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• pp.29-40
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• 2022

Objective : This study assessed the effect of a combination of Korean medicine on a thyroid papillary cancer patient who was diagnosed with local lymph node metastasis after thyroidectomy and lymph node dissection but did not want surgery. Methods : Gami-Palmultang administration and moxibustion(large Bmoxa cautery) were performed for six years. Treatment outcomes were evaluated with Brief Fatigue Inventory (BFI), Numerical Rating Scale (NRS), Insomnia Severity Index (ISI), Functional Assessment of Cancer Therapy-General (FACT-G), blood test/ CT imaging results, and patient's statements. Results : After the treatment, all symptoms have been alleviated, the quality of life has increased, and it has been maintained without further metastasis of tumors for six years. Conclusion : Korean medicine treatment along with active observation can be an alternative to patients who do not want surgical treatment after recurrence of local lymph nodes in thyroid papillary cancer, and can have positive results in improving the quality of life.

• Archives of Plastic Surgery
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• v.50 no.3
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• pp.225-232
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• 2023

In retrospect, the irony of this story began with the first meeting of these co-authors-in of all places, Coimbatore, India, in 2008, at the 12th International Perforator Flap Course. Here the junior author [hereafter "jp"] demonstrated his unparalleled skills in networking, and soon thereafter journeyed some 11,073 km to Allentown, U.S. to peruse the operating room and clinics of the senior author [sic. ggh] in action. Within 2 years jp orchestrated the presentation of the 14th International Perforator Flap Course, so ggh with great anticipation flew only 6,830 miles to reach Seoul, Korea for his first time. But four years more elapsed before ggh returned again to Korea to be a visiting professor, all the while not quite sure why any Korean would want anything from a country doctor who resided in nowheresville Allentown, Pennsylvania. Yet, an extraordinary fact then was to be unveiled, about which ggh was totally ignorant. The pioneer of plastic surgery in Korea, the first Korean to have completed an accredited plastic surgery fellowship, by coincidence had accomplished all this in . . . . . Allentown. The collegial relationship that evolved between these co-authors, who met by chance, indeed had a precedent coincidence! Was this "by chance" alone or predestination? Amazingly, in a way similar, the origin of plastic surgery itself in Korea also had Allentown connections. As a tribute to Lew Jae-duk, this important story must be here told, so let us now retrace his past in Allentown so we can find how the future was to be not so far away.

• Nuclear Engineering and Technology
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• v.55 no.4
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• pp.1485-1494
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• 2023

The bow of the nuclear fuel assembly is a well-known phenomenon. One of the vital criteria during the history of nuclear fuel development has been fuel assembly's mechanical stability. Once present, the fuel assembly bow can lead to safety issues like excessive water gap and power redistribution or even incomplete rod insertion (IRI). The extensive bow can result in assembly handling and loading problems. This is why the fuel assembly's bow is one of the most often controlled geometrical factors during periodic fuel inspections for VVER when compared e.g. to on-site fuel rod gap measurements or other instrumental measurements performed on-site. Our proposed screening method uses existing video records for fuel inspection. We establish video frames normalization and aggregation for the purposes of bow measurement. The whole process is done by digital image processing algorithms which analyze rotations of video frames, extract angles whose source is the fuel set torsion, and reconstruct torsion schema. This approach provides results comparable to the commonly utilized method. We tested this new approach in real operation on 19 fuel assemblies with different campaign numbers and designs, where the average deviation from other methods was less than 2 % on average. Due to the fact, that the method has not yet been validated during full scale measurements of the fuel inspection, the preliminary results stand for that we recommend this method as a complementary part of standard bow measurement procedures to increase measurement robustness, lower time consumption and preserve or increase accuracy. After completed validation it is expected that the proposed method allows standalone fuel assembly bow measurements.

• Genomics & Informatics
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• v.21 no.1
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• pp.4.1-4.18
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• 2023

Coronavirus disease 2019 (COVID-19) is an inflammatory and infectious disease caused by severe acute respiratory syndrome coronavirus 2 virus with a complex pathophysiology. While COVID-19 vaccines and boosters are available, treatment of the disease is primarily supportive and symptomatic. Several research have suggested the potential of herbal medicines as an adjunctive treatment for the disease. A popular herbal medicine approved in the Philippines for the treatment of acute respiratory disease is Vitex negundo L. In fact, the Department of Science and Technology of the Philippines has funded a clinical trial to establish its potential as an adjunctive treatment for COVID-19. Here, we utilized network pharmacology and molecular docking in determining pivotal targets of Vitex negundo compounds against COVID-19. The results showed that significant targets of Vitex negundo compounds in COVID-19 are CSB, SERPINE1, and PLG which code for cathepsin B, plasminogen activator inhibitor-1, and plasminogen, respectively. Molecular docking revealed that α-terpinyl acetate and geranyl acetate have good binding affinity in cathepsin B; 6,7,4-trimethoxyflavanone, 5,6,7,8,3',4',5'-heptamethoxyflavone, artemetin, demethylnobiletin, gardenin A, geranyl acetate in plasminogen; and 7,8,4-trimethoxyflavanone in plasminogen activator inhibitor-1. While the results are promising, these are bound to the limitations of computational methods and further experimentation are needed to completely establish the molecular mechanisms of Vitex negundo against COVID-19.

• International conference on construction engineering and project management
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• 2022.06a
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• pp.877-885
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• 2022

Vision-based activity recognition has been widely attempted at construction sites to estimate productivity and enhance workers' health and safety. Previous studies have focused on extracting an individual worker's postural information from sequential image frames for activity recognition. However, various trades of workers perform different tasks with similar postural patterns, which degrades the performance of activity recognition based on postural information. To this end, this research exploited a concept of human-object interaction, the interaction between a worker and their surrounding objects, considering the fact that trade workers interact with a specific object (e.g., working tools or construction materials) relevant to their trades. This research developed an approach to understand the context from sequential image frames based on four features: posture, object, spatial features, and temporal feature. Both posture and object features were used to analyze the interaction between the worker and the target object, and the other two features were used to detect movements from the entire region of image frames in both temporal and spatial domains. The developed approach used convolutional neural networks (CNN) for feature extractors and activity classifiers and long short-term memory (LSTM) was also used as an activity classifier. The developed approach provided an average accuracy of 85.96% for classifying 12 target construction tasks performed by two trades of workers, which was higher than two benchmark models. This experimental result indicated that integrating a concept of the human-object interaction offers great benefits in activity recognition when various trade workers coexist in a scene.

• Journal of Digestive Cancer Research
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• v.6 no.1
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• pp.32-35
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• 2018

Non-Hodgkin's lymphoma is known to be a rare and unusual cause of biliary obstruction. We report a case of biliary obstruction that a 25-year-old male showed icteric sclera and yellow discoloration of his skin caused by metastasis of non-Hodgkin lymphoma. Initial imaging & endoscopic work-up led us to an impression of either cholangiocarcinoma or IgG4-related disease, yet the pathological results weren't diagnostic. Through our thorough re-examination, we found a 5cm sized round, fixed, non-tender sternal mass, and additional imaging studies were suggestive of lymphoma, which was also consistent with the results of incisional chest wall biopsy. Biliary obstruction by lymphoma was successfully treated by endoscopic plastic stent insertion procedure and chemotherapy. Although it is widely accepted that lymphoma accounts for very few portion of malignant biliary obstruction, due to the fact that lymphoma and cholangiocarcinoma are often indistinguishable, careful diagnostic approach should be done.

• Journal of the Korean Geotechnical Society
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• v.40 no.1
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• pp.39-46
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• 2024

Artificial recharge systems have been employed to solve drought problems due to global climate change. Despite the increased usage, the applications of artificial recharge systems are limited by clogging problems, which reduce recharge rates. In this study, the soil texture and mineral characteristics of alluvial soil in a planned artificial recharge system area were investigated to evaluate the possibility of chemical clogging during the injection of stream water. The primary minerals contained in the clastic particles are quartz, K-feldspar, plagioclase, and biotite, and the secondary minerals filling the pore space are illite, kaolinite and Fe-oxide. The fact that carbonate and sulfate are observed as secondary minerals in the pore space suggests that chemical clogging has not occurred by the interaction between the groundwater and surface water in the study area. Thus, monitoring soil properties, e.g., the formation and growth of secondary minerals in the pore space, is required to investigate the possibility of chemical clogging in artificial recharge systems.

• Nuclear Engineering and Technology
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• v.56 no.1
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• pp.247-256
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• 2024

The glass series modified by tungsten oxide was created using the compounds (75-x) B₂O₃- 10SrCO₃- 8TeO₂- 7ZnO - xWO₃, where x = 0, 1, 5, 10, 22, 27, 34, and 40% mole percentage. A UV-visible spectrophotometer and thermogravimetric-differential thermal analysis (TG-DTA) methods were employed to characterize the specimen's optical and phase transition attributes, respectively. The mass-attenuation coefficient (AC) of all created glasses from BSTZW0 to BSTZ7 was estimated using Geant4 code from 0.05 to 3 MeV and compared to the XCOM software results, with a relative difference of less than 2% between the two results. The increase of WO₃ percentage lead to an increase in the Linear-AC at each studied energy, and this is mainly due to the fact that the higher the percentage of WO₃ in the glass increases its density which causes an increase in the Linear-AC, so an energy of 0.06 MeV, as an example, the values of the Linear-AC was 4.009, 4.509, 5.442, 6812, 8.564, 9.856, 10.999 and 11.628 cm^-1 form BSTZW0 too BSTZW7, respectively. The Half-VL (value layer), Mean-FP (free path), Tenth-VL, and Radiation attenuation performance (RAP) were also calculated for the current BSTZW-glass samples and revealed that BSTZW7 had the best gamma ray attenuation performance at all discussed energies when compared to other studied glass samples.