• Journal of Digital Convergence
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• v.20 no.5
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• pp.317-322
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• 2022

In general, life jackets are worn by people in critical situations on the water to rise to the surface without falling into water, and life jackets simply serve to prevent sinking, but do not actively help rescue disaster areas in critical situations early. In order to solve this problem, a device that automatically generates a distress signal in an emergency situation was developed. When the survivor is in hand for a while, the distress signal generator is automatically separated from the life jacket, allowing information such as location values and other information to be transmitted wirelessly and a rescue signal using LED light. As a result of the experiment, when submerged in water, the life jacket and the distress signal generator were automatically separated, and the result of wireless transmission of the coordinate value of the location received by the GPS was confirmed. By using this, the location of the distress or missing person can be identified, which can be quickly replaced in case of an emergency

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.21 no.3
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• pp.42-52
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• 2022

Bus Information System (BIS) services are expanding nationwide to small and medium-sized cities, including large cities, and user satisfaction is continuously improving. In addition, technology development related to improving reliability of bus arrival time and improvement research to minimize errors continue, and above all, the importance of information accuracy is emerging. In this study, accuracy performance was evaluated using LSTM, a machine learning method, and compared with existing methodologies such as Kalman filter and neural network. As a result of analyzing the standard error for the actual travel time and predicted values, it was analyzed that the LSTM machine learning method has about 1% higher accuracy and the standard error is about 10 seconds lower than the existing algorithm. On the other hand, 109 out of 162 sections (67.3%) were analyzed to be excellent, indicating that the LSTM method was not entirely excellent. It is judged that further improved accuracy prediction will be possible when algorithms are fused through section characteristic analysis.

• Journal of the Korean Society of Propulsion Engineers
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• v.25 no.6
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• pp.60-65
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• 2021

In this paper, we examined the ignition possibility of the propellant depending on its non-uniform composition of aluminum. Impact and friction sensitivity was investigated by arbitrarily changing the aluminum content in the range of 14~20% to simulate the non-uniform distribution of aluminum in the propellant. As a result of measuring the impact sensitivity, the 50% ignition energy and minimum ignition energy have values around 50 J regardless of the aluminum content. This means that the propellant does not become sensitive to impact even if the aluminum content is increased. On the other hand, the friction sensitivity result shows that as the aluminum content increases, the 50% ignition force and minimum ignition forces were decreased, and thus the propellant becomes sensitive. "Hot Spot" model of propellant ignition is applied, the space inside the propellant is momentarily compressed and ignited by friction stimuli rather than by impact stimuli.

• Structural Engineering and Mechanics
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• v.85 no.5
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• pp.679-691
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• 2023

Many codes allow designers to use the bending moment diagram computed by elastic analysis and modify it by a certain amount of moment redistribution (MR) to account for plastic behaviour of continuous beams. However, several researchers indicated that the MR at the ultimate limit state (𝛽_u) for some beams deviate significantly from the specified values of various codes. This paper examines the applicability of the provisions on 𝛽_u in ACI 318-19 and Eurocode 2 through numerical investigations and comprehensively explores the influencing factors. The results show that some parameters not considered in those codes influence 𝛽_u to a certain extent, where the ratio of tensile reinforcement ratio at intermediate support to tensile reinforcement ratio at midspan (𝜌_s1/𝜌_s2) and load type are crucial parameters to consider. The specific combination of these two parameters may make the codes overestimate or significantly underestimate the 𝛽_u. On the other hand, the yield state of both critical sections is found to have an important influence on the influence degree of each parameter on 𝛽_u. The yield conditions are investigated, and an empirical judgment equation is proposed. In addition, the influence laws of the critical parameters on 𝛽_u have been further proved by theoretical derivation. Finally, due to 𝜀_t is found to have a better linear correlation with 𝛽_u than x_u/d, equations as a function of 𝜀_t for predicting the 𝛽_u of continuous beams under the two loads are proposed, respectively.

• The Research Journal of the Costume Culture
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• v.31 no.4
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• pp.558-571
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• 2023

In recent years, young Chinese consumers have become more favorably inclined toward products relating to traditional culture. Therefore, this study aimed to develop a textile design that incorporates traditional Chinese patterns and cultural symbolism that will appeal to consumers from the MZ generation (millennials and Generation Z). Through a literature search for traditional Chinese patterns and symbols regarded as auspicious, our design concept and motives were established. We selected peony, lotus, and frog motifs as representative of a "wealth and eternal prosperity" design theme. In textile design work 1, we used hand drawing and watercolor techniques, color transformation with Adobe Photoshop, and colorway and end-use 3D simulation with TexPro. The 3D simulation work suggests that this textile pattern is suitable for women's outerwear, mufflers, and tote bags. Textile design work 2 conveyed the 'wealth and eternal prosperity' design theme and had a graceful mood that embodied the nobility of the lotus flower whilst also encompassing the symbolism of money and status. The end design is a modern reinterpretation of traditional Chinese patterns and motifs. As such, it is hoped that it will satisfy the needs of young consumers for cultural values yet offer a unique new aesthetic distinct from existing textile designs. These qualities can be expected to enhance the competitive market value of textiles bearing this design.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.59 no.3
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• pp.261-263
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• 2023

Recently, universities of fisheries and institutions related to fisheries are actively carrying out a project to build new fisheries training ships. These new fisheries training ships are significantly larger in size and longer in length than the previous ships. In addition, these new ships basically have space that can accommodate more than 100 crew and passenger. On the other hand, they are excluded from IMO maneuverability evaluation since the size of these ships are still less than 100 m in length (LBP). These results have had an impact on the study of maneuverability of fishing vessels including the fisheries training ships. Against these backgrounds, the authors conducted a study to estimate the maneuvering characteristics of fisheries training ship Baek-Kyung according to depth in order to prepare a maneuvering characteristic index that enables the large fisheries training ships to navigate more safely using a modified empirical formula. It was confirmed that the maneuvering characteristics of Baek-Kyung changed significantly as the values of the hydrodynamic force coefficients changed as the water depth gradually decreased from around 1.5 (approx. 8 m in depth) of the ratio of the water depth to the ship draft. The results of this study will not only help navigators understand the maneuvering characteristics of Baek-Kyung, but also serve as an indicator when navigating in shallow water. In addition, the accumulation of these results will serve as a basis for future study on maneuverability of fishing vessel types.

• Journal of Practical Agriculture & Fisheries Research
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• v.11 no.1
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• pp.63-77
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• 2009

The decrease in the farming rates of agricultural produce importing countries has led to concerns over stable food supply and food safety and this situation demands a change in awareness on agricultural problems arising from the depletion of natural resources and environmental destruction. To preserve agriculture, importing countries are emphasizing the various roles of agriculture in order to revive its multi-functional aspects. It is obvious that differentiated strategies are needed to create values from agricultural production, and a liberal arts education can play an important role in making these strategies. However, training programs for future agricultural CEOs of the Korea National Agricultural College(KNAC) attaches too much importance on production skill and management rather than focusing on a liberal arts education. On the other hand, Poolmoo Ecological Agriculture Course carried out by Poolmoo Agriculture Technical High School located in Hongseong-Gun, Chungnam Province (which puts a high value on ecological fanning) gives more weight on a liberal arts education, taking up more than 50% of the curriculum. Also, the National Farmers Academy in Japan which reformed its whole system in 2008, has started various liberal arts educational programs. The Academy fosters creative agricultural management, attractive rural development enhancing a comfortable rural life and educates on the future of Japanese food and international environment. It is expected that the ecological and cultural roles of farming will grow in the future. So, what the KNAC needs is to increase its liberal arts educational programs and various cultural experiences in its educational curriculum to promote agricultural marketing with cultural knowledge and sensitivity.

• Journal of Korean Society of Rural Planning
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• v.28 no.1
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• pp.99-108
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• 2022

This study measured the importance and satisfaction of the values related to 'New Ruralism' using the IPA(Importance-Performance Analysis) technique by the rural leaders' group. In the result, the satisfaction value was evaluated lower in the importance of 'landscape and ecological resource conservation', 'settlement environment', and 'population' related items. On the other hand, the items of 'tourism resource management', 'landscape damage', and 'landscape and ecological resource conservation' showed high satisfaction. Therefore, the leaders' group of Gochang-gun perceived the importance of local tourism image, landscape damage prevention, settlement environment, and rural landscape in 'New Ruralism' management. However, the leaders' group valued lower in the items of population, ecological value and natural and historical tourist sites. This seems to be a characteristic of the leaders' group mainly engaged in agriculture. Through factor analysis, the six items excluded from the analysis were considered important factors in 'New Ruralism' in Gochang-gun through a review of previous studies. Still, the leaders' group of Gochang-gun did not recognize them as important items in the rural resource. However, these items will be able to contribute to the development of 'New Ruralism' in Gochang-gun, and it is necessary to improve the awareness of the leader group. Even if local governments or experts present an ideal goal for rural development, it is difficult to achieve the goals if there is a difference from the perception of residents. Therefore, it is important to understand the perception of 'New Ruralism' of the leaders' group who plays an important role in regional development projects.

• Medical Lasers
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• v.8 no.1
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• pp.7-12
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• 2019

Background and Objectives Skin and soft tissue defects can be treated according to a range of strategies, such as local flap, skin graft, biological dressing, or free flap. On the other hand, free tissue transfer usually leaves a distinct scar with an inconsistency of color or hypertrophy. This problem is highlighted if the defect is located on the face, which could have devastating effects on a patient's psychosocial health. Materials and Methods The authors used an erbium : yttrium-aluminum-garnet (Er:YAG) laser to resurface the free flap skin and match the color with the surrounding facial skin. This study evaluated the effectiveness of laser skin resurfacing on the harmonious color matching of transferred flap. Patients who had undergone laser resurfacing on facial flap skin between January 2014 and December 2018 were reviewed retrospectively. An ablative 2,940-nm fractional Er:YAG laser treatment was delivered to the entire flap skin at 21 J/cm² with the treatment end-point of pinpoint bleeding. Several months later, the clinical photographs were analyzed. The L^*a^*b^* color co-ordinates of both the flap and surrounding normal skin were measured using Adobe Photoshop. The L^*a^*b^* color difference (ΔE) for the scar and normal surrounding skin were calculated using the following equation: ${\Delta}E=\sqrt{({\Delta}L)^2+({\Delta}a)^2+({\Delta}b)^2}$ Results All five patients were satisfied with the more natural appearance of the flaps. The ΔE values decreased significantly from the pre-treatment mean value of 19.64 to the post-treatment mean value of 11.39 (Wilcoxon signed-rank test, p = 0.043). Conclusion Ablative laser resurfacing can improve the aesthetic outcome of free tissue transfer on the face.

• Advances in concrete construction
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• v.15 no.1
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• pp.23-39
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• 2023

One of the important problems of concrete placing is the concrete compaction, which can affect the strength, durability and apparent quality of the hardened concrete. Therefore, vibrating operations might be accompanied by much noise and the need for training the involved workers, while inappropriate functioning can result in many problems. One of the most important methods to solve these problems is to utilize self-compacting cementitious composites instead of the normal concrete. Due to their benefits of these new materials, such as high tensile, compressive, and flexural strength, have drawn the researchers' attention to this type of cementitious composite more than ever. In this experimental investigation, six mixing designs were selected as a base to acquire the best mechanical properties. Moreover, forty-eight rectangular composite panels with dimensions of 300 mm × 400 mm and two thickness values of 30 mm and 50 mm were cast and tested to compare the flexural and impact energy absorption. Steel fibers with volume fractions of 0%, 0.5% and 1% and with lengths of 25 mm and 50 mm were imposed in order to prepare the required cement composites. In this research, the composite panels with two thicknesses of 30 mm and 50 mm, classified into 12 different groups, were cast and tested under three-point flexural bending and repeated drop weight impact test, respectively. Also, the examination and comparison of flexural energy absorption with impact energy absorption were one of the other aims of this research. The obtained results showed that the addition of fibers of longer length improved the mechanical properties of specimens. On the other hand, the findings of the flexural and impact test on the self-compacting composite panels indicated a stronger influence of the long-length fibers.