• The Journal of the Korea institute of electronic communication sciences
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• v.17 no.1
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• pp.71-76
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• 2022

Since brightness is proportional to the operating current, a method of connecting several LEDs in series and driving with a constant current source is widely used for driving circuits of LED lights. Because several LEDs are connected in series, if some LEDs open due to a fault, the current path is broken and all other LEDs connected in series are turned off. In this paper, we designed a circuit to solve this problem by connecting a Zener diode having a breakdown voltage of about 0.4V higher than the LED operating voltage in parallel with each LED to create a current bypass in case of LED failure. Through simulations and experiments, it was confirmed that the current of the Zener diode hardly flows when the LED is operating normally, and that the Zener diode stably operates as a current bypass when the LED fails.

• Journal of Forest and Environmental Science
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• v.37 no.4
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• pp.309-314
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• 2021

This study aimed to enhance seed productivity and secure genetic resources for Pinus densiflora for. multicaulis. We analyzed the characteristics of cone and seed generated by control pollination between Pinus densiflora (PD) and Pinus densiflora for. multicaulis (PDM). The highest number of cone scales (63.0) was obtained from the self-pollinated (sp) PDM clone B (PDM-sp-B), whereas the lowest number of cone scales (44.7) was obtained from two combinations designated as PDM-A×PD-075 and PDM-A×PD-0111. Both female parents of the hybrids were PDM-A. The highest seed production capacity (80.8) was obtained from the open-pollinated (op) PDM clone B (PDM-op-B). The seed potentials of PDM-B×PD-0111, PDM-op-A, and PDM-sp-B were 67.4, 66.5, and 63.1, respectively. The highest number of fertile scales (41.5) was obtained from PDM-op-B, and the lowest number of fertile scales (28.8) was obtained from PDM-A×PD-075. The total number of aborted ovules and 1st aborted ovules was not statistically significant in the mating design. The cross combination of PDM-B×PD-0111 had the highest number (34.8) of filled seeds and the lowest number of 2nd aborted ovules (5.2) and empty seeds (9). PDM-op-B had the highest number of developed seeds (47.6), although the number of empty seeds was the highest (41.2). Therefore, we conclude that the mating design of PDM-B×PD-0111 is useful for future breeding programs to improve seed yield of PDM. Our results showed that there was a strong correlation between the following two parameter pairs: number of scales and number of fertile scales, and the number of fertility scales and seeds potential (r=0.89 and r=0.84, respectively; both p<0.01).

• Nuclear Engineering and Technology
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• v.54 no.7
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• pp.2444-2452
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• 2022

The field-programmable gate array (FPGA) is gaining popularity in industrial automation such as nuclear power plant instrumentation and control (I&C) systems due to the benefits of having non-existence of operating system, minimum software errors, and minimum common reason failures. Separate functions can be processed individually and in parallel on the same integrated circuit using FPGAs in comparison to the conventional microprocessor-based systems used in any plant operations. The use of FPGAs offers the potential to minimize complexity and the accompanying difficulty of securing regulatory approval, as well as provide superior protection against obsolescence. Wireless sensor networks (WSNs) are a new technology for acquiring and processing plant data wirelessly in which sensor nodes are configured for real-time signal processing, data acquisition, and monitoring. ZigBee (IEEE 802.15.4) is an open worldwide standard for minimum power, low-cost machine-to-machine (M2M), and internet of things (IoT) enabled wireless network communication. It is always a challenge to follow the specific topology when different Zigbee nodes are placed in a large network such as a plant. The research article focuses on the hardware chip design of different topological structures supported by ZigBee that can be used for monitoring and controlling the different operations of the plant and evaluates the performance in Vitex-5 FPGA hardware. The research work presents a strategy for configuring FPGA with ZigBee sensor nodes when communicating in a large area such as an industrial plant for real-time monitoring.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.22 no.5
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• pp.55-61
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• 2022

With the rapid development of information technology, Metaverse and Non-Fungible Token (hereinafter referred to as NFT) technology will not only create new supply and demand markets for digital art creators, but also for existing art writers. As interest in and trading of virtual assets and coins increases, so does the demand for digital art trading in the NFT market. This study examines the theoretical content of NFTs, blockchains, and Metaverse, and analyzes various expressions of NFT art that are currently popular. As the case study, 100 projects were selected and analyzed in the overall OpenSea ranking, which included 2D graphics, 3D graphics and motion graphics works. Then, from the perspective of creators, the graphic styles of NFT digital art are divided into 4 types: 2D graphics, 3D graphics, 2D dynamic graphics, 3D dynamic graphics, and analyzed and studied. It is hoped that in the future, this study can suggest the direction of creating graphic styles to digital art NFT creators.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.39 no.6
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• pp.599-607
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• 2021

Street-view images, which are omnidirectional scenes centered on a specific location on the road, can provide various obstacle information for the pedestrians. Pedestrian network data for the navigation services should reflect the up-to-date obstacle information to ensure the mobility of pedestrians, including people with disabilities. In this study, the object detection model was trained for the bollard as a major obstacle in Seoul using street-view images and a deep learning algorithm. Also, a process for updating information about the presence and number of bollards as obstacle properties for the crosswalk node through spatial matching between the detected bollards and the pedestrian nodes was proposed. The missing crosswalk information can also be updated concurrently by the proposed process. The proposed approach is appropriate for crowdsourcing data as the model trained using the street-view images can be applied to photos taken with a smartphone while walking. Through additional training with various obstacles captured in the street-view images, it is expected to enable efficient information update about obstacles on the road.

• Journal of Appropriate Technology
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• v.6 no.2
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• pp.226-237
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• 2020

As the number of reported COVID-19 cases rises around the world, regions affected by the virus are taking serious measures to contain its spread. Face shields are one of the highest-need personal protective equipment (PPE) during COVID-19 pandemic. Beyond traditional face masks, as known cases of the coronavirus soar, currently there is a significant shortage of face shields around the world. In response, the protective face shields were designed and fabricated with open-source 3D modelling software and 3D printing technology, respectively. Our face shield consisted of two parts only; a reusable 3D printed headband and a visor made of transparent plastic sheet, as barrier. The resulting 3D printed face shields are affordable, lightweight, one-size-fits-most and ready-to-wear with minimal assemblies, and go on easily over glass, goggle and face mask. To ensure being donated to the healthcare professionals without risk infected by any pathogens, the 3D printed face shields were successfully be disinfected with ultraviolet germicidal irradiation (UVGI dosage of 1000 mJ/cm²) and 70% alcohol. For routine disinfection a UVGI chamber was designed and optimized to provide uniform UV-C illumination with an appreciated fluence for complete decontamination. More than 1,000 face shields were produced already and donated to the special hospitals for COVID-19 patients, quarantines, government and medical agencies in Ethiopia as well as in East-African countries. With certainty, our intention goes beyond the hospitals and other first responders, but not limited for all those who have to stay in the service or be in contact with many other people in the time of COVID-19 pandemic.

• Journal of Korean Medical classics
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• v.34 no.3
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• pp.125-145
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• 2021

Objectives : To examine the meaning of 'geuk(極)' and 'geuk(克)' of Cheon-gi and Insa respectively, for better translation of the contents and to understand the structure of the Donguisusebowon cosmology. Methods : The meanings of the characters '極' and '克' based on examples in the Daxue were examined together with content-related books such as the Shujing and the Shijing. Related concepts such as Taiji and Huangji were investigated as well. Results & Conclusions : Through investigation of the character usages and contexts in the Daxue, the archetypes of the two characters '極' and '克' were discovered. Based on these findings, the characteristics of Cheon-gi and Insa were thoroughly studied, which enabled better understanding of the structure of the world view that has been created by their integration. 'Geuk(極)' refers to Cheon-gi as the open world wherein all beings of different horizons are connected through a common principle. 'Geuk(克)' refers to Insa as an individual world that could be fully established by manifestation of one's moral abilities that lie within everybody. The two worlds integrate with each other, becoming two poles of the world humans belong to, while the human heart, in correspondence to these two worlds, create two poles within themselves, of which one pursues the public world while the other rejects the personal.

• Journal of Korean Academy of Nursing
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• v.52 no.2
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• pp.187-201
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• 2022

Purpose: This study discovered a substantive theory of the experience and process of peer support work among people with mental illness. Methods: The participants were members of community-based mental health facilities and had been working as peer supporters for more than six months. The data were collected through in-depth interviews with twelve participants and analyzed using Corbin and Strauss's grounded theory approach. Results: The core category was "becoming a healer going with patients in the journey of recovery," and the core phenomenon was "identity confusion as a peer supporter." The causal conditions were "starting peer support work without certainty" and "standing at the boundary between the therapist and patient." The intervening conditions were "willingness to become a successful peer supporter," "feeling a sense of homogeneity with the patient," "accepting the mental illness," and "support from people around." The action and interaction strategies were "letting go of greed," "being open about oneself," "developing professional skills," "maintaining wellness in the body and mind," and "being with the patient." The consequences were "becoming a useful person," "changing attitude toward life," "expansion of the sense of self-existence," "recovering from mental illness," and "discovering a role as peer supporter." Finally, the substantive theory of "becoming a healer going with patients in the journey of recovery" was derived. Conclusion: This study provides a holistic understanding of peer support work and the implications of interventions to help people with mental illness in a person-centered recovery process.

• Journal of Digital Policy
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• v.1 no.2
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• pp.1-8
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• 2022

In case of a dangerous situation, the roof, which serves as an emergency exit, must be open in case of fire according to the Fire Act. However, when the roof door is opened, it has become a place of various incidents and accidents such as illegal entry, crime, and suicide. As a result, it is a reality to close the roof door in terms of facility management to prevent crime, various incidents, and accidents. Accordingly, the government is pushing to legislate regulations on housing construction standards, etc. that mandate the installation of electronic automatic opening and closing devices on rooftop doors. Therefore, in this paper, an intelligent emergency door opening/closing device system is proposed. To this end, an intelligent emergency door opening and closing system was developed by linking wired and wireless access counting and AI image analysis. Finally, it is possible to build a wireless communication-based integrated management platform that provides remote control and history management in a centralized method of device status real-time monitoring and event alarm.

• Korean Journal of Exercise Nutrition
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• v.25 no.3
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• pp.8-15
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• 2021

[Purpose] Excessive reactive oxygen species (ROS) induced by prolonged high-intensity exercise can cause structural and functional damage. Antioxidant polyphenol supplementation, which reduces ROS levels, may improve high-intensity exercise performance. We evaluated the effect of lychee fruit extract, which contains high levels of low-molecular-weight oligomerized polyphenols, on high-intensity exercise performance. [Methods] Ten male athletes were included in an open-label trial that consisted of control and intervention phases, with a 7-day washout period between phases. The participants were administered oligomerized lychee fruit extract for seven days, whereas no intervention was given in the control phase. High-intensity intermittent exercise and the Wingate test were performed. The power output, blood lactate levels, reactive oxygen metabolite levels, biological antioxidant potential, heart rate, and rate of perceived exertion were measured. [Results] The average power output was significantly higher in the intervention phase than in the control phase (P < 0.01), while the change in blood lactate levels was significantly lower in the intervention phase than in the control phase (P < 0.05). The average heart rate was significantly higher in the intervention phase than in the control phase (P < 0.05), without changing the rate of perceived exertion. Although there was no difference in reactive oxygen metabolite levels between the phase, the change in biological antioxidant potential was larger in the intervention phase than in the control phase (P = 0.06). The Wingate test showed no significant differences between the phase. [Conclusion] Short-term loading with oligomerized lychee fruit extract may increase performance during high-intensity intermittent exercise by improving metabolism.