• Structural Engineering and Mechanics
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• v.87 no.5
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• pp.461-473
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• 2023

This study aims to solve for nonlinear cylindrical shell systems with a semi-analytical and numerical approach implementing the P-T method. The procedures and conditions for such a study are presented in practically solving and analyzing the cylindrical shell systems. An analytical model for a nonlinear thick cylindrical shell (TCS) is established on the basis of the stress function and Reddy's higher-order shear deformation theory (HSDT). According to Reddy's HSDT, Hooke's law in three dimensions, and the von-Kármán equation, the stress-strain relations are developed for the thick cylindrical shell systems, and the three coupled nonlinear governing equations are thus established and discretized as per the Galerkin method, for implementing the P-T method. The solution generated with the approach is continuous everywhere in the entire time domain considered. The approach proposed can also be used to numerically solve and analyze the nonlinear shell systems. The procedures and recurrence relations for numerical solutions of shell systems are presented. To demonstrate the application of the approach in numerically solving for nonlinear cylindrical shell systems, a specific nonlinear cylindrical shell system subjected to an external excitation is solved numerically. In numerically solving for the system, the present approach shows higher efficiency, accuracy, and reliability in comparison with that of the Runge-Kutta method. The approach with the P-T method presented is practically sound especially when continuous and high-quality numerical solutions for the shell systems are considered.

• Nuclear Engineering and Technology
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• v.54 no.12
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• pp.4698-4707
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• 2022

As part of the ICRP Task Group 103 project, we developed ten thyroid models for the pediatric mesh-type reference computational phantoms (MRCPs). The thyroid is not only a radiosensitive target organ needed for effective dose calculation but an important source region particularly for radioactive iodines. The thyroid models for the pediatric MRCPs were constructed by converting those of the pediatric voxel-type reference computational phantoms (VRCPs) in ICRP Publication 143 to a high-quality mesh format, faithfully maintaining their original topology. At the same time, we improved several anatomical parameters of the thyroid models for the pediatric MRCPs, including the mass, overlying tissue thickness, location, and isthmus dimensions. Absorbed doses to the thyroid for the pediatric MRCPs for photon external exposures were calculated and compared with those of the pediatric VRCPs, finding that the differences between the MRCPs and VRCPs were not significant except for very low energies (<0.03 MeV). Specific absorbed fractions (target ⟵ thyroid) for photon internal exposures were also compared, where significant differences were frequently observed especially for the target organs/tissues close to the thyroid (e.g., a factor of ~1.2-~327 for the thymus as a target) due mainly to anatomical improvement of the MRCP thyroid models.

• Computers and Concrete
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• v.31 no.5
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• pp.457-468
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• 2023

Buildings, bridges, and dams are examples of civil infrastructure that play an important role in public life. These structures are prone to structural variations over time as a result of external forces that might disrupt the operation of the structures, cause structural integrity issues, and raise safety concerns for the occupants. Therefore, monitoring the state of a structure, also known as structural health monitoring (SHM), is essential. Owing to the emergence of the fourth industrial revolution, next-generation sensors, such as wireless sensors, UAVs, and video cameras, have recently been utilized to improve the quality and efficiency of building forensics. This study presents a method that uses a target-based system to estimate the dynamic displacement and its corresponding dynamic properties of structures using UAV-based video. A laboratory experiment was performed to verify the tracking technique using a shaking table to excite an SDOF specimen and comparing the results between a laser distance sensor, accelerometer, and fixed camera. Then a field test was conducted to validate the proposed framework. One target marker is placed on the specimen, and another marker is attached to the ground, which serves as a stationary reference to account for the undesired UAV movement. The results from the UAV and stationary camera displayed a root mean square (RMS) error of 2.02% for the displacement, and after post-processing the displacement data using an OMA method, the identified natural frequency and damping ratio showed significant accuracy and similarities. The findings illustrate the capabilities and reliabilities of the methodology using UAV to evaluate the dynamic properties of structures.

• The Journal of the Convergence on Culture Technology
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• v.9 no.2
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• pp.207-213
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• 2023

Korea is facing a population cliff and a decline in the fertility rate, and the competition rate for recruiting officers in our military is rapidly decreasing every year. This situation is a serious problem in terms of national security and requires efforts to obtain excellent manpower. To this end, it is necessary to understand their occupational values through consideration of the MZ generation, which is the main recruitment target of the military, and to find diagnosis and solutions for each problem by closely analyzing the military's internal and external environment based on their understanding of soldiers as a job. Therefore, we diagnose the current situation in consideration of military specificity, examine the occupational values of the MZ generation, which is a resource for military officers recruitment. Since the subject of military officer acquisition is the MZ generation, efforts are needed to focus on occupational values of MZ generations.

• Journal of the Korean Society of Food Culture
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• v.21 no.6
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• pp.695-701
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• 2006

This study is based on the utilization of pine mushroom for processing products by development of pine mushroom Jung-Gwa. The results were summarized as follows: Pine mushroom Jung-Gwa were prepared with four different amounts (20, 30, 40, 50%) of honey. Pine mushroom Jung-Gwa color value was the highest by 20% soaking honey-water product and 40% soaking honey-water product was the lowest. Strength and hardness of 20% soaking honey-water product was the highest. Appearance to product of 50% soaking honey-water was the highest preference by all age of except 20's. The honey content of more and more external appearance preference was became higher. Product of 40% soaking honey-water was best by flavor of pine mushroom Jung-Gwa. A sugary tastes comparison 50% soaking honey water to 40% soaking honey water was not distinction. The texture was appeared a statistically significant difference by products of 20%, 30% soaking honey-water. Product of 20% soaking honey-water was favorite in 20's and product of 30% soaking honey-water was favorite in 30's. In overall preference test for pine mushroom Jung-Gwa of 40% soaking honey water was preferred by all age. Oligosaccharide helped geriatric diseases and cheaper. Thus this study used oligosaccharide but the result was not a statistically significant difference of pine mushroom Jung-Gwa products quality by comparison honey-water to oligosaccharide. Therefore oligosaccharide utilization products was thought worth a lot more by processing price and functional.

• The Journal of Pediatrics of Korean Medicine
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• v.37 no.4
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• pp.34-52
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• 2023

Objective This study aimed to evaluate the effect of herbal medicines on transient hip synovitis (TSH) in children. Methods We searched 10 Korean, English, Japanese, and Chinese databases for studies published up to September 19, 2023. Randomized controlled trials (RCTs) evaluating the effect of herbal medicines on TSH levels in children were included. The Cochrane risk of bias was used to evaluate the quality of the studies. A meta-analysis was conducted according to outcome measurements, such as total effective rate (TER), visual analog score (VAS), time to pain relief, and hip joint mobility disorder disappearance time, using the Review Manager website. Results Eleven RCTs were included in this study. TER in the treatment group was significantly higher than in the control group. The duration of pain relief was significantly shorter in the treatment group than in the control group. The VAS score of the treatment group was significantly lower than that of the control group, although the statistical heterogeneity was substantial. The hip joint mobility disorder disappeared in the treatment group treated with external therapy, which was significantly shorter than in the control group. Regarding safety, two of the 11 studies reported that there were no adverse events. Conclusions Herbal medicines are effective in the treatment of TSH in children. However, the safety of herbal medicines should be carefully considered due to the lack of data.

• Atmosphere
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• v.33 no.5
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• pp.561-570
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• 2023

In order to improve the predictability of marine high-impacts weather such as typhoon and high waves, the marine observation network is an essential because it could be rapidly changed by strong air-sea interaction. In this regard, the National Institute of Meteorological Sciences, Korea Meteorological Administration (NIMS/KMA) has promoted the Argo float observation program since 2001 to participate in the International Argo program. In this study, current status and future direction of the NIMS/KMA Argo program are presented through the internal meeting and external expert forum. To date, a total of 264 Argo floats have been deployed into the offshore around the Korean Peninsula and the Northwestern Pacific Ocean. The real-time and delayed modes quality control (QC) system of Argo data was developed, and an official regional data assembling center (call-sign 'KM') was run. In 2002, the Argo homepage was established for the systematic management and dissemination of Argo data for domestic and international users. The future goal of the NIMS/KMA Argo program is to improve response to the marine high-impacts weather through a marine environment monitoring and observing system. The promotion strategy for this is divided into four areas: strengthening policy communication, developing observation strategies, promoting utilization research, and activating international cooperation.

• Food Science and Preservation
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• v.30 no.2
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• pp.205-223
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• 2023

Fresh mushrooms are vulnerable to browning and tissue changes after harvest. This study monitored the external appearance, physicochemical quality indicators, and nutritional and functional components of a white beech mushroom (Hypsizygus marmoreus) variety (EG2020) newly developed in Korea during cold storage for up to 42 days. Two existing varieties of white H. marmoreus, namely H6 from Korea and HKT from Japan, were used for comparison. The mechanical texture of EG2020 was superior to H6 and HKT due to the increasing hardness of the pileus with time. Browning, in terms of the total color difference during storage, was found to be the most severe in HKT. In terms of composition, EG2020 had the highest total free sugar content, a large amount of organic acids, and higher sugar content than H6 and HKT. EG2020 also contained the largest amount of 𝛽-glucan, and its amount increased during storage. In sensory evaluation, EG2020 received higher scores than HKT in flavor, taste, appearance, and texture. Therefore, the EG2020 variety is more stable than HKT during storage and distribution.

• Hip & pelvis
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• v.35 no.4
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• pp.268-276
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• 2023

Purpose: Resection remains the most reliable treatment for established heterotopic ossification, despite questions regarding its effectiveness due to the potential for complications. This study evaluated the clinical outcomes and complications of neurogenic heterotopic ossification (NHO) resection in stroke patients' ankylosed hips. Materials and Methods: We retrospectively analyzed nine hip NHO resections performed on seven patients from 2010 to 2018. The pre- and postoperative range of motion of the operated hip were compared. Analysis of postoperative complications, including infection, recurrence, iatrogenic fracture, and neurovascular injury was performed. Results: The mean operative time was 132.78±21.08 minutes, with a mean hemoglobin drop of 3.06±0.82 g/dL within the first postoperative week. The mean duration of postoperative follow-up was 52.08±28.72 months for all patients. Postoperative range of motion showed improvement from preoperative. Flexion and external rotation (mean, 58.89±30.60° and 16.67±18.03°, respectively) showed the greatest gain of motion of the operated hip joint. Postoperative infections resolved in two cases through surgical debridement, and one case required conversion to total hip arthroplasty due to instability. There were no recurrences, iatrogenic fractures, or neurovascular injuries. Conclusion: Resection is a beneficial intervention for restoring the functional range of motion of the hip in order to improve the quality of life for patients with NHO and neurological disorders. We recommend performance of a minimal resection to achieve a targeted functional arc of motion in order to minimize the risk of postoperative complications.

• Journal of Animal Science and Technology
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• v.66 no.2
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• pp.279-294
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• 2024

Agriculture has played a significant role in the national economy, contributing to food security, driving economic growth, and safeguarding the dietary habits of the population. Korean agriculture has been compelled to focus on intensive farming due to its limited cultivation area, excessive input costs, and the limitations of agricultural mechanization. In the Republic of Korea (R.O.K), the concept of environmentally friendly animal agriculture began to be introduced in the early 2000s. This concept ultimately aims to cultivate sustainable animal agriculture (SAA) through environmentally friendly production practices, ensuring the healthy rearing of animals to supply safe animal products. Despite the government's efforts, there are still significant challenges in implementing environmentally friendly agriculture and SAA in the R.O.K. Therefore, the objective of this review is to establish the direction that the animal agriculture sector should take in the era of climate crisis, and to develop effective strategies for SAA tailored to the current situation in the R.O.K by examining the trends in SAA in the U.S. The animal agriculture sector in the U.S. has been working towards creating a SAA system where humans, animals, and the environment can coexist through government initiatives, industry research, technological support, and individual efforts. Efforts have been made to reduce emissions like carbon, and improve factors affecting the environment such as the carbon footprint, odor, and greenhouse gases associated with animal agriculture processes for animals such as cattle and pigs. The transition of the U.S. towards SAA appears to be driven by both external goals related to addressing climate change and the primary objectives of responding to the demand for safe animal products, expanding consumption, and securing competitiveness in overseas export markets. The demand for animal welfare, organic animal products, and processed goods has been increasing in the U.S. consumer market. A major factor in the transformation of the U.S. animal agriculture sector in terms of livestock specifications is attributed to environmentally friendly practices such as high-quality feed, heat stress reduction, improvements in reproductive ability and growth period reduction, and efforts in animal genetic enhancement.