• Journal of the Microelectronics and Packaging Society
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• v.29 no.2
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• pp.65-71
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• 2022

In the case of Mobile PKG Trend is in a situation where a decrease in Mold Top Margin is inevitable due to its miniaturization and high capacity product requirements. However, conventional laser marking technology has an average depth of deep, and when applied to narrow top margin products, PKG strength is expected to decrease due to overlapping processing, and reliability is reduced due to poor quality such as chip damage due to laser exposure. Therefore, we have secured the technology through research on low-depth laser marking solutions that can accommodate narrow top margin products. As a result of the evaluation of applicable technology application for PKG development products, it was verified that the marking depth decreased by 67% reduced and the PKG strength increased by 12%. Furthermore, the quality verification of Laser Damage that can occur through PKG Mechanical analysis was performed, and no Chip Damage defects were found. This ensured the stability of mass production application quality.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.25 no.7
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• pp.890-895
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• 2021

Recently, the "Act of Serious Disasters, etc" was enacted and institutional and social interest in safety accidents is increasing. In this paper, we analyze statistical data published by government agency on safety accidents that occur in manufacturing sites, and compare various object detection models based on deep learning to build a model to determine dangerous situations to reduce the occurrence of safety accidents. The data-set was directly constructed by collecting images from CCTVs at the manufacturing site, and the YOLO-v4, SSD, CenterNet models were used as training data and evaluation data for learning. As a result, the YOLO-v4 model obtained a value of 81% of mAP. It is meaningful to select a class in an industrial field and directly build a dataset to learn a model, and it is thought that it can be used as an initial research data for a system that determines a risk situation and infers it.

• Smart Structures and Systems
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• v.30 no.6
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• pp.673-686
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• 2022

Deep learning algorithms for Structural Health Monitoring (SHM) have been extracting the interest of researchers and engineers. These algorithms commonly used loss functions and evaluation indices like the mean square error (MSE) which were not originally designed for SHM problems. An updated loss function which was specifically constructed for deep-learning-based structural damage detection problems has been proposed in this study. By tuning the coefficients of the loss function, the weights for damage localization and quantification can be adapted to the real situation and the deep learning network can avoid unnecessary iterations on damage localization and focus on the damage severity identification. To prove efficiency of the proposed method, structural damage detection using convolutional neural networks (CNNs) was conducted on a truss bridge model. Results showed that the validation curve with the updated loss function converged faster than the traditional MSE. Data augmentation was conducted to improve the anti-noise ability of the proposed method. For reducing the training time, the normalized modal strain energy change (NMSEC) was extracted, and the principal component analysis (PCA) was adopted for dimension reduction. The results showed that the training time was reduced by 90% and the damage identification accuracy could also have a slight increase. Furthermore, the effect of different modes and elements on the training dataset was also analyzed. The proposed method could greatly improve the performance for structural damage detection on both the training time and detection accuracy.

• Journal of the Korea Institute of Military Science and Technology
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• v.25 no.6
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• pp.617-627
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• 2022

Military training is an essential item for the fundamental problem of war. However, there has always been a problem that many resources are consumed, causing spatial and environmental pollution. The concepts of defense modeling and simulation and CGF(Computer Generated Force) using computer technology began to appear to improve this problem. The Naval Operations, Resources Analysis Model(NORAM) developed by the Republic of Korea Navy is also a DEVS(Discrete Event Simulation)-based naval virtual force analysis model. The current NORAM is a battle experiment conducted by an operator, and parameter values such as maneuver and armament operation for individual objects for each situation are evaluated. In spite of our research conducted evolutionary, supervised, reinforcement learning, in this paper, we introduce our design of a scenario creation model based on evolutionary learning using genetic algorithms. For verification, the NORAM is loaded with our model to analyze wartime engagements. Human-level tactical scenario creation capability is secured by automatically generating enemy tactical scenarios for human-designed Blue Army tactical scenarios.

• Journal of the Korean Society of Industry Convergence
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• v.25 no.6_2
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• pp.1097-1102
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• 2022

With the continuous development of the current industry, the current global environment is in a very serious situation, with resource supply and demand dependent on imports and huge costs for waste disposal due to the depletion of resources and mass generation of industrial waste. Its limitations have already been revealed in many fields, and the importance of re-manufacturing is drawing attention as a countermeasure to these problems. Re-manufacturing aims to recover products that are in the aging and disposal stages, recover to performance close to new products, and re-commercialize them. Among them, most of the machine tools are made of materials such as steel and cast iron with large structures, and raw materials are widely used when producing new products. In addition, since a lot of carbon is generated due to production, it is an object that can obtain a great re-manufacturing effect. Planner millers belonging to large machine tools are one of the machine tool equipment that can greatly reduce resources and energy through re-manufacturing because the structure is very large and the casting is several to tens of tons. Through this machine tool, performance tests and results are derived on the development of re-manufacturing source technology and domestic servo motor and CNC control device.

• Korean Journal of Veterinary Service
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• v.45 no.2
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• pp.87-99
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• 2022

A novel porcine circovirus 4 (PCV4) was recently emerged in Chinese and Korean pig herds, which provided epidemiological situation where three pathogenic PCVs, PCV2, PCV3, and newly emerged PCV4, could co-infect pig herds in these countries. In this study, a new triplex quantitative real-time polymerase chain reaction (tqPCR) method was developed for the rapid and differential detection of these viruses. The assay specifically amplified each viral capsid gene, whereas no other porcine pathogenic genes were detected. The detection limit of the assay was below 10 copies/µL and the assay showed high repeatability and reproducibility. In the clinical evaluation using 1476 clinical samples from 198 Korean pig farms, the detection rates of PCV2, PCV3 and PCV4 by the tqPCR assay were 13.8%, 25.4%, and 3.8%, respectively, which were 100% agreement with those of previously reported monoplex qPCR assays for PCV2, PCV3, and PCV4, with a κ value (95% CI) of 1 (1.00~1.00). The prevalence of PCV2, PCV3, and PCV4 at the farm levels were 46.5%, 63.6%, and 19.7%, respectively. The co-infection analysis for tested pig farms showed that single infection rates for PCV2, PCV3, and PCV4 were 28.8%, 44.4%, and 9.6%, respectively, the dual infection rates of PCV2 and PCV3, PCV2 and PCV4, and PCV3 and PCV4 were 12.6%, 3.5%, and 5.1%, respectively, and the triple infection rate for PCV2, PCV3, and PCV4 was 1.5%. These results demonstrate that three pathogenic PCVs are widely spread, and their co-infections are common in Korean pig herds, and the newly developed tqPCR assay will be useful for etiological and epidemiological studies of these pathogenic PCVs.

• The Journal of Korean Obstetrics and Gynecology
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• v.36 no.2
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• pp.36-54
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• 2023

Objectives: This study was aimed to develop a Korean Medicine (KM) clinical practice guideline (CPG) of Nausea and Vomiting of Pregnancy (NVP). Methods: We conducted a questionnaire survey targeting KM doctors belonging to the Association of Korean Medicine by e-mail. We received 1,023 responds, and analyzed the answers. Results: 1. 83.0% of respondents knew the concepts and contents of CPG, and 98.1% had practical use plan. 2. 82.1% of respondents used pattern identification diagnosis for NVP patients, and the most commonly diagnosed pattern was spleen-stomach weakness (脾胃虛弱) with 41.3%. 3. The most frequently used treatment for NVP patients was KM combined treatment (46.7%). Herbal medicine+acupuncture (46.8%) was most used among KM combined treatments, and herbal medicine (37.1%) was most used among KM single treatments. 4. Among the contents of CPG for NVP, the fields of interest were selected in the order of KM treatment, KM-Western medicine cooperative treatment, KM diagnosis, prevention and regimen management. In the 'diagnosis part', the use of the symptom evaluation scale questionnaire was 41.8%, higher than the KM pattern diagnosis (34.4%). In the 'treatment part', herbal medicine accounted for 33.8%, higher than that of acupuncture (including electro-acupuncture) at 23.7%. 5. As for the expected development effects, opinions on evidence-based, safety, clinical use, and standardization were the most common. Conclusions: We figured out KM doctors' recognition of KM clinical practice guideline, clinical diagnosis, treatment on NVP to make the contents of the CPG reflecting the clinical situation.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.22 no.2
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• pp.29-43
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• 2023

It is necessary to grasp the characteristics of traffic flow passing through a specific road section and the topological structure of the road in advance in order to quickly prepare a movement management strategy in the event of a disaster or disaster. It is because it can be an essential basis for road managers to assess vulnerabilities by microscopic road units and then establish appropriate monitoring and management measures for disasters or disaster situations. Therefore, this study presented spatial density, time occupancy, and betweenness centrality index to evaluate vulnerabilities by road link in the city department and defined spatial-temporal and topological vulnerabilities by clustering analysis based on distance and density. From the results of this study, road administrators can manage vulnerabilities by characterizing each road link group. It is expected to be used as primary data for selecting priority control points and presenting optimal routes in the event of a disaster or disaster.

• Journal of the Korean Society of Industry Convergence
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• v.26 no.3
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• pp.421-431
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• 2023

Recently, the destructive power of typhoons is continuously increasing due to the influence of global warming. In a situation where the installation of floating wind turbines is increasing around the world, concerns about the huge loss and collapse of floating offshore wind turbines due to strong typhoons are deepening. Regarding to the safe operation of the floating offshore wind turbine, the development of a new type of disconnectable mooring system is required. A new fairlead chain stopper considered in this study is devised to more easily attach or detach the floating offshore wind turbine with mooring lines comparing to other disconnectable mooring apparatuses. In order to investigate the structural safety of the initial design of fairlead chain stopper that can be applied to MW-class floating type offshore wind turbine, scale-down structural models were produced using a 3-D printer and structural tests were performed on the models. For the structural tests of the scale-down models, tensile specimens of acrylonitrile butadiene styrene material that was used in the 3-D printing were prepared, and the material properties were evaluated by performing the tensile tests. The finite element analysis of fairlead chain stopper was performed by applying the material properties obtained from the tensile tests and the same load and boundary conditions as in the scale-down model structural tests. Through the finite element analysis, the structural weak parts on the fairlead chain stopper were reviewed. The structural model tests were performed considering the main load conditions of fairlead chain stopper, and the test results were compared to the finite element analysis. Through the results of this study, it was possible to experimentally verify the structural safety of the initial design of fairlead chain stopper. It is also judged that the study results can be usefully used to improve the structural strength of fairlead chain stopper in a detailed design stage.

• Journal of The Korean Society of Integrative Medicine
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• v.11 no.2
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• pp.231-242
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• 2023

Purpose : This study aimed to identify ways to improve the quality of physical therapy research and ultimately review the current situation to improve evidence-based decision-making in physical therapy. Methods : For better evidence-based decision-making in physical therapy, researchers should review the quality assessment of articles in more detail and report their findings for valid and appropriate level of evidence and strength of recommendations. The level of evidence affects how well the findings are derived from well-designed literature. The evaluation of the evidence focuses primarily on the study design and the degree of bias that may compromise the validity of the findings. The final recommendation is based on a combination of the study design and literature quality. To uncover gems of information in each paper, a risk of bias assessment should be performed after the literature has been initially selected. Results : Researchers should consider the complexity of the intervention, appropriate grouping, and calculation of effect sizes for the intervention. Researchers conducting systematic reviews should provide a detailed description of the quality assessment performed and present a detailed analysis of their interpretation of the results. The results of systematic reviews and meta-analyses should be interpreted with caution and include a risk of bias assessment. Guidelines for the level of evidence and strength of recommendations should be developed and utilized more broadly to improve reporting practices in physical therapy. Conclusion : Researchers should be knowledgeable about the strengths and limitations of each study design and methodology. In the future, researchers will also need to improve their ability to critically evaluate their findings, given the potential for their results to influence clinical practice.