• Korean Journal of Acupuncture
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• v.40 no.4
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• pp.184-193
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• 2023

Objectives : The purpose of this study is to understand the temperature characteristics depending on the thickness and material of the needle used with the Electronic Warm Acupuncture Device (EWAD). Methods : We controlled experimental environment and measured temperature changes of a silicon phantom in which K-type thermocouples were inserted at depths of 2, 7 mm. EWAD perfomed with acupuncture needles of various thicknesses (0.25×60 mm, 0.40×60 mm, and 0.50×60 mm) and materials (Gold 0.40×50 mm). We set non-needle (only heated with EWAD skin heater) group as a control group. Results : The maximum temperature and temperature changes of 0.40 mm, 0.50 mm needle group were significantly higher than the non-needle group. The highest temperature range in all needle groups was 0.50 mm needle group (41.44±0.31℃). However, the 0.25 mm needle group was not significantly different from the non-needle group. Maximum temperature of gold needle group was significantly higher than stainless steel needle group. Temperature changes of gold needle group were higher than stainless steel group at the depth of 7 mm. Conclusions : It was found that needle thickness and material of acupuncture had an effect on the temperature of the EWAD. When performing EWAD treatment, consideration of thickness and material of acupuncture is needed. Future research is needed using phantoms that can reflect actual clinical situations and better mimic the human body.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.43 no.6
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• pp.709-719
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• 2023

In general, most of the electrical equipment responsible for control within power plants is housed in self-standing cabinets. These cabinets are typically fixed to a slab using post-installed anchors. Although the fixation method of using post-installed anchors provides stability, there is a risk of conductor failure due to external forces, including moments. However, the performance assessment of current anchors is only evaluated through uniaxial material tests. Therefore, the primary purpose of this study is to compare the static performance of post-installed anchors, considering on-site installation conditions, with their performance in material tests and to analyze the behavioral characteristics of the anchors. While conducting experiments using actual cabinets would be ideal, practical and spatial constraints make this approach difficult. As an alternative, experiments were conducted using a test specimen consisting of a steel column and a support. As a result, the pull-out performance of anchors reflecting on-site installation conditions was measured to be about 10% higher than that observed in material tests. The trends in load reduction and the point of maximum performance for the anchors also differed. To verify the reliability of the experimental study, a 3D FEM analysis was performed, which will provide predictive information on the loads transferred to the post-installed anchors for structural performance evaluations of electrical cabinets using shaking table test in the future.

• Nuclear Engineering and Technology
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• v.55 no.10
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• pp.3543-3548
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• 2023

Shutdown chemistry evolution is performed in nuclear power plants at each refueling outage (RFO) to establish safe conditions to open system and minimize inventory of corrosion products in the reactor coolant system (RCS). After hydrogen peroxide is added to RCS during shutdown chemistry evolution, corrosion products are released and are removed by filters and ion exchange resins in the chemical volume control system (CVCS). Shutdown chemistry evolution including RCS clean-up time to remove released corrosion products impacts the critical path schedule during RFOs. The estimation of clean-up time prior to RFO can provide more reliable actions for RCS clean-up operations and transients to operators during shutdown chemistry. Electric Power Research Institute (EPRI) shutdown calculator (SDC) enables to provide clean-up time by Co-58 peak activity through operational data from nuclear power plants (NPPs). In this study, we have investigated the results of EPRI SDC by shutdown chemistry data of Co-58 activity using NPP data from previous cycles and modeled the estimated clean-up time by EPRI SDC using average Co-58 activity of the NPP. We selected two RFO data from the NPP to evaluate EPRI SDC results using the purification time to reach to 1.3 mCi/cc of Co-58 after hydrogen peroxide addition. Comparing two RFO data, the similar purification time between actual and computed data by EPRI SDC, 0.92 and 1.74 h respectively, was observed with the deviation of 3.7-7.2%. As the modeling the estimated clean-up time, we calculated average Co-58 peak concentration for normal cycles after cycle 10 and applied two-sigma (2σ, 95.4%) for predicted Co-58 peak concentration as upper and lower values compared to the average data. For the verification of modeling, shutdown chemistry data for RFO 17 was used. Predicted RCS clean-up time with lower and upper values was between 21.05 and 27.58 h, and clean-up time for RFO 17 was 24.75 h, within the predicted time band. Therefore, our calculated modeling band was validated. This approach can be identified that the advantage of the modeling for clean-up time with SDC is that the primary prediction of shutdown chemistry plans can be performed more reliably during shutdown chemistry. This research can contribute to improving the efficiency and safety of shutdown chemistry evolution in nuclear power plants.

• Journal of Drive and Control
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• v.20 no.4
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• pp.115-122
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• 2023

This study utilized a discrete element method (DEM) simulation, as one of the virtual field trials, to predict the impact of tillage depth on the rotary blade shaft during rotavator tilling. The virtual field for the simulation was generated according to soil properties observed in an actual field. Following the generation of particles for the virtual field, a sequence of calibration steps followed to align the mechanical properties more closely with those of real soil. Calibration was conducted with a focus on bulk density and shear torque, resulting in calibration errors of just 0.02% for bulk density and 0.52% for shear torque. The prediction of the load on a rotary tiller's blade shaft involved a three-pronged approach, considering shaft torque, draft force, and vertical force. In terms of shaft torque, the values exhibited significant increases of 42.34% and 36.91% for every 5-centimeter increment in tillage depth. Similarly, the vertical force saw substantial growth by 40.41% and 36.08% for every 5-centimeter increment. In contrast, the variation in draft force based on tillage depth was comparatively lower at 18.49% and 0.96%, indicating that the effect of tillage depth on draft force was less pronounced than its impact on shaft torque and vertical force. From a perspective of agricultural machinery research, this study provides valuable insights into the DEM soil modeling process, accounting for changes in soil properties with varying tillage depths. These findings are expected to be instrumental in future agricultural machinery design studies.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.23 no.1
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• pp.153-166
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• 2024

The digitalization of tasks for smart construction requires the smooth exchange of digital data among stakeholders to be effective, but there is a lack of digital data standardization and utilization methods. This paper proposes a digital construction information structure to transform information from road construction sites into digital formats. The study targets include significant tasks, such as work planning, scheduling, safety management, and quality control. The key to the construction information structure is separating construction information into objects and activities, defining unit works by combining these two types of information to ensure flexibility in representing and modifying construction information. The objects and activities have their respective hierarchical structures, which are defined flexibly to match the actual content. This structure achieves both efficiency and detail. The pilot structure was applied to highway construction projects and implemented digitally using general formats. This study enables the digitalization of road construction processes that closely resemble reality, accelerating the digital transformation of the civil engineering industry by developing a digital twin of the entire road construction lifecycle.

• Journal of Korean Medical classics
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• v.37 no.2
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• pp.49-76
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• 2024

Objectives : The purpose of this paper is to examine the mechanism and treatment of the Zangfu warm disease in the Beijiqianjinyaofang. Methods : This study examined the Zangfu warm disease content in the Beijiqianjinyaofang, Shanghanzongbinglun, Saninfang, based on the Neijing explanation of the pathological mechanism. Treatment was analyzed among the three texts in terms of their similarity and difference. Results & Conclusions : 1. Zangfu warm disease is caused by seasonally inappropriate qi, which is infectious, epidemic, and seasonal. 2. While the Qingjinqian disease pattern was explained in terms of the relationship between Shaoyin and Shaoyang, the actual disease pattern happened more in the Taiyang channel, and partly in the Shaoyang channel. For treatment of Fu deficiency pattern, the Chaihudihuangtang was listed in the Qianjinyaofang and the Shanghanzongbinglun, while in the Sanyinfang, the formula was modified to extinguish heat and thin phlegm, while reinforcing healthy qi. 3. The Chimaifei disease pattern was explained in terms of the relationship between Shaoyin and Taiyang that is deeply associated with Wei qi. For treatment of Fu deficiency the Qianjinyaofang and Shanghanzongbinglun used the Shigaodihuangtang, while the Sanyinfang reinforced healthy qi and eliminated pathogenic qi. 4. The Huangrousui disease pattern was explained as being caused by problems in the Taiyin and Yangming, in which the Triple Burner fails to control and manage cold dampness. In treating Zang excessiveness, the Qianjinyaofang and Shanghanzongbinglun used the Xuanshenhanshuishitang, while the Sanyinfang instructed to reinforce healthy qi and eliminate pathogenic qi. In treating Fu deficiency, the Sanyinfang instructed to warm the center and dry dampness, tonifying the Spleen and reinforcing qi. 5. The Baiqili disease pattern was explained within the relationship between Taiyin and Taiyang. In treating Fu deficiency, the Qianjinyaofang and Shanghanzongbinglun used the Shigaoxingrentang, while the Sanyinfang instructed to reinforce healthy qi and eliminate pathogenic qi. In treating Zang excessiveness, the Qianjinyaofang and Shanghanzongbinglun used the Shigaocongbaitang, while the Sanyinfang instructed to reinforce healthy qi and eliminate pathogenic qi. 6. The Heiguwen disease pattern was explained as being caused by stagnation and obstruction in the Triple Burner due to clash between Taiyang and Shaoyin. In treating Zang excessiveness, the Qianjinyaofang and Shanghanzongbinglun used the Kushenshigaotang, while the Sanyinfang instructed to reinforce healthy qi and eliminate pathogenic qi. The Zangfu Warm Disease is a infectious disease concept which is based on the Five Zang that integrates the meridian aspect together with the Six Fu with which there is an external/internal relationship. This concept and treatment could be considered in dealing with COVID-19.

• Journal of Navigation and Port Research
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• v.47 no.6
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• pp.367-375
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• 2023

This study developed a new distance metric for vessel trajectories, applicable to marine traffic control services in the Korean coastal waters. The proposed metric is designed through the weighted summation of the traditional Hausdorff distance, which measures the similarity between spatiotemporal data and incorporates the differences in the average Speed Over Ground (SOG) and the variance in Course Over Ground (COG) between two trajectories. To validate the effectiveness of this new metric, a comparative analysis was conducted using the actual Automatic Identification System (AIS) trajectory data, in conjunction with an agglomerative clustering algorithm. Data visualizations were used to confirm that the results of trajectory clustering, with the new metric, reflect geographical distances and the distribution of vessel behavioral characteristics more accurately, than conventional metrics such as the Hausdorff distance and Dynamic Time Warping distance. Quantitatively, based on the Davies-Bouldin index, the clustering results were found to be superior or comparable and demonstrated exceptional efficiency in computational distance calculation.

• The Journal of the Acoustical Society of Korea
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• v.43 no.1
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• pp.103-111
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• 2024

Axial-flow fans are used to transport fluids in relatively low-pressure flow regimes, and a variety of design variables are employed. The tip geometry of an axial fan plays a dominant role in its flow and noise performance, and two of the most prominent flow phenomena are the tip vortex and the tip leakage vortex that occur at the tip of the blade. Various studies have been conducted to control these three-dimensional flow structures, and winglet geometries have been developed in the aircraft field to suppress wingtip vortices and increase efficiency. In this study, a numerical and experimental study was conducted to analyze the effect of winglet geometry applied to an axial fan blade for an air conditioner outdoor unit. The unsteady Reynolds-Averaged Navier-Stokes (RANS) equation and the FfocwsWilliams and Hawkings (FW-H) equation were numerically solved based on computational fluid dynamics techniques to analyze the three-dimensional flow structure and flow noise numerically, and the validity of the numerical method was verified by comparison with experimental results. The differences in the formation of tip vortex and tip leakage vortex depending on the winglet geometry were compared through a three-dimensional flow field, and the resulting aerodynamic performance was quantitatively compared. In addition, the effect of winglet geometry on flow noise was evaluated by numerically simulating noise based on the predicted flow field. A prototype of the target fan model was built, and flow and noise experiments were conducted to evaluate the actual performance quantitatively.

• Journal of Ginseng Culture
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• v.6
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• pp.80-104
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• 2024

Ginseng, a representative medicinal plant of South Korea, is also highly valued in North Korea. However, due to limited access to information about North Korea, the actual cultivation, research and development trends, and related industry status of ginseng in North Korea are not well known. In this study, we aimed to understand the current status and research trends of the ginseng industry in North Korea based on limited available literature. In the North Korean pharmacopoeia, ginseng is referred to as "Koryo ginseng" and is defined as the roots of 6-year-old ginseng cultivated in the Kaesong region. The pharmacopoeia includes 22 types of ginseng preparations. In addition, 10 ginseng preparations are included in North Korea's Essential Drug List, and various health supplements, cosmetics, and toothpastes containing ginseng have been developed, distributed, and sold. Since 2014, the ginseng industry and research in North Korea have become more active overall. During this period, the ginseng cultivation area in Kaesong has been significantly expanded, and the facilities have been renovated. The Kaesong Koryo Ginseng Processing Plant has been equipped with sterilized, modernized facilities since 2016 and has been in operation. Since 2017, there has been a growing interest in quality control research, leading to the introduction of quality management regulations and certification systems in 2019. In the 1990s, there was significant research on ginseng product development, and since the 2000s, studies on the pharmacological effects and clinical research of ginseng have been reported. Additionally, research on ginseng cultivation and ginseng processing industries to increase yield has been emphasized. Ginseng, as a representative medicinal crop of Korea, holds great importance for both South and North Korea. Given its significance and the potential for synergy through mutual cooperation, ginseng serves as an ideal subject for inter-Korean exchange and collaboration.

• Journal of the Korean Society for information Management
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• v.41 no.1
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• pp.509-536
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• 2024

The purpose of this study is to develop a metadata AP for managing the person and organization name authority data in the National Debt Redemption Movement Digital Archive, a small-scale digital archive. The design principles and core metadata elements were derived by analyzing person/organization(group or corporateBody) metadata standards, implementation practices, and guidelines of libraries and archives, and mapped to the National Debt Redemption Movement person/organization name thesaurus data and the Wikidata Linked Metadata Model, resulting in 10 elements in the identification area, 14 elements in the content area, 8 elements in the relationship area, and 4 elements in the control area. A simple structure schema was applied so that it can be applied even in small organizations, and for interoperability, the schema was proposed with reference to DublinCore and SKOS schemes, and the applicability was confirmed based on actual data. The results of this study can be utilized as a basis for institutions that recognize the importance of data management but have difficulty in applying it in practice, when they want to prepare a system for managing their own authority data.