• Journal of the Korean Institute of Intelligent Systems
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• v.9 no.4
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• pp.420-425
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• 1999

The maximum demand controller is an electrical equipment installed at the consumer side of power system for monitoring the electrical energy consumed during every integrating period and preventing the target maximum demand (MD) being exceeded by disconnecting sheddable loads. By avoiding the peak loads and spreading the energy requirement the controller contributes to maximizing the utility factor of the generator systems. It results in not only saving the energy but also reducing the budget for constructing the natural base facilities by keeping thc number of generating plants ~ninimumT. he conventional MD controllers often bring about the large number of control actions during the every inteyating period and/or undesirable loaddisconnecting operations during the beginning stage of the integrating period. These make the users aviod the MD controllers. In this paper. fuzzy control technique is used to get around the disadvantages of the conventional MD control system. The proposed MD controller consists of the predictor module and the fuzzy MD control module. The proposed forecasting method uses the SOFM neural network model, differently from time series analysis, and thus it has inherent advantages of neural network such as parallel processing, generalization and robustness. The MD fuzzy controller determines the sensitivity of control action based on the time closed to the end of the integrating period and the urgency of the load interrupting action along the predicted demand reaching the target. The experimental results show that the proposed method has more accurate forecastinglcontrol performance than the previous methods.

• Experimental and Molecular Medicine
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• v.50 no.12
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• pp.12.1-12.14
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• 2018

Osteoporosis develops with high prevalence in both postmenopausal women and hypogonadal men. Osteoporosis results in significant morbidity, but no cure has been established. Mesenchymal stem cells (MSCs) critically contribute to bone homeostasis and possess potent immunomodulatory/anti-inflammatory capability. Here, we investigated the therapeutic efficacy of using an infusion of MSCs to treat sex hormone-deficient bone loss and its underlying mechanisms. In particular, we compared the impacts of MSC cytotherapy in the two genders with the aim of examining potential gender differences. Using the gonadectomy (GNX) model, we confirmed that the osteoporotic phenotypes were substantially consistent between female and male mice. Importantly, systemic MSC transplantation (MSCT) not only rescued trabecular bone loss in GNX mice but also restored cortical bone mass and bone quality. Unexpectedly, no differences were detected between the genders. Furthermore, MSCT demonstrated an equal efficiency in rectifying the bone remodeling balance in both genders of GNX animals, as proven by the comparable recovery of bone formation and parallel normalization of bone resorption. Mechanistically, using green fluorescent protein (GFP)-based cell-tracing, we demonstrated rapid engraftment but poor inhabitation of donor MSCs in the GNX recipient bone marrow of each gender. Alternatively, MSCT uniformly reduced the $CD3^+T$-cell population and suppressed the serum levels of inflammatory cytokines in reversing female and male GNX osteoporosis, which was attributed to the ability of the MSC to induce T-cell apoptosis. Immunosuppression in the microenvironment eventually led to functional recovery of endogenous MSCs, which resulted in restored osteogenesis and normalized behavior to modulate osteoclastogenesis. Collectively, these data revealed recipient sexually monomorphic responses to MSC therapy in gonadal steroid deficiency-induced osteoporosis via immunosuppression/anti-inflammation and resident stem cell recovery.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.11
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• pp.96-104
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• 2018

Military vessels are complex weapon systems consisting of various integrated onboard equipment. Since their acquisition of military equipment takes a long period of time and a prototype ship is deployed and tested, vessel development has relied on its proprietary process. However, due to the growing complexity of onboard equipment technology, application of systems engineering (SE) process has become indispensable. Nonetheless, an effective design process complementing the existing design with the SE has not yet been developed. As such, we have studied an improved basic design process for submarines based on SE. To do so, we analyzed the processes for the basic design, technical review, and requirement management. Included reviews and requirements are SRR, SFR and PDR, and SSRS, SSS, and SSDD. By combining the results in the SE framework, we built an improved basic design process that can be applied in parallel with the SE-based technical review and requirement management. To assess the process, we applied our proposed model to the submarine development undergoing the basic design phase. It is possible to effectively manage the requirements, design artifacts and improve traceability, and also utilize them as test and evaluation materials. The SE-based basic design process is expected to be useful in other kinds of vessel design.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.6
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• pp.142-149
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• 2019

In this study, the past erosion history and current status in the CHUNG-UI beach of Eulwang-dong, Jung-gu, Incheon-Si, South Korea were investigated and analyzed the wave with wave-induced current to investigate the causes of coastal erosion. As a result, the significant wave height ($H_{1/3}$) was in the range of 0.07~1.57 m and the mean value was 0.21 m. The maximum wave height ($H_{max}$) was in the range of 0.02-4.76m and the mean value was 0.27m. The vertical wave height and cycles were estimated through numerical model experiments of wave transformation. The 50-year frequency design wave height ranged from 0.82m to 3.75m. As a result of the experiment of wave-induced current, wave-induced current in the CHUNG-UI beach was decreased after the installation of the Detached breakwater and the Jetty. On the other hand, when the crest elevation was increased up to 5 m, there was no significant change, but when the crest elevation was increased to 8m, strong wave-induced current occurred around the submerged breakwaters due to lowered depth of water. In addition, the main erosion of the CHUNG-UI beach is due to the intensive invasion of the wave characteristics coming from the outer sea into the white sandy beach. The deformation of the wave centered on the front of the sandy beach caused additional longshore currents flowing parallel to the sandy beach and rip currents in the transverse direction, thus confirming that the longshore sediment was moved out of the front and out of the sea. The results of this study can be used as preliminary data for the recovery of the sand and the selection of efficient erosion prevention facilities.

• Journal of the Korean Wood Science and Technology
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• v.47 no.4
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• pp.519-532
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• 2019

The objectives of this study were to evaluate the effects of shelling ratio and resin content on the properties of bamboo oriented strand board (BOSB) from betung (Dendrocalamus asper) and to determine the correlation between the results of dynamic and static bending tests. Strands were steam-treated at $126^{\circ}C$ for 1 h under 0.14 MPa pressure and followed by washing with 1% NaOH solution. Three-layer BOSB with the core layer perpendicular to the surface was formed with shelling ratios (face:core ratio) of 30:70; 40:60; 50:50; 60:40 and binded with 7% and 8% of phenol formaldehyde (PF) resin with the addition of 1% of wax. The evaluation of physical and mechanical properties of BOSB was conducted in accordance with the JIS A 5908:2003 standard and the results were compared with CSA 0437.0 standard for commercial OSB (Grade O-1). Non-destructive testing was conducted using Metriguard Model 239A Stress Wave Timer which has a wave propagation time from 1 to $9,999{\mu}s$ and a resolution of $1{\mu}s$. BOSB with 8% resin content showed better physical and mechanical properties than those with 7% resin content. The increase of the face layer ratio improved the strength of BOSB in parallel direction to the grain. The results suggested that shelling ratio of 50:50 could be used as a simple way to reduce PF resin requirements from 8% to 7% and to meet the requirements of CSA 0437.0 standard. The results of non-destructive and destructive tests showed a strong correlation, suggesting that non-destructive test can be used to estimate the bending properties of BOSB.

• Journal of Korea Technology Innovation Society
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• v.21 no.3
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• pp.992-1020
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• 2018

The purpose of this study is to investigate the ways to enhance the creativity of R & D teams of government-funded research institutes through systematic empirical studies. For this purpose, a research model was established based on existing research on group creativity and verified through empirical studies. Specifically, This study first attempts to investigate the influence that team diversity, team cohesion, team autonomy and team efficacy have on team creativity. Second, it intends to verify the mediating effects of team efficacy between team characteristics and team creativity. An empirical study was conducted on 102 R & D teams of government-funded research institutes. In the team creativity measurement, the evaluation by the leaders and the self evaluation of the members were performed in parallel. This is to increase the accuracy of the evaluation and to compare the differences of the viewpoints of the two subjects. The result of the analysis demonstrated that team cohesion among the others had a positive influence on team creativity, and that team efficacy possessed certain positive qualities in mediating the relationship between team diversity, team autonomy, and team creativity. Based on these findings, this study discussed its academic implications as well as its practical limitations, and made suggestions on future research tasks that remain.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.19 no.2
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• pp.187-192
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• 2019

Hybrid power storage system with emergency power function for demand management and power outage minimizes the investment cost in the building of buildings and factories requiring emergency power generation facilities, We propose a new business model by developing technology that can secure economical efficiency by reducing power cost at all times. Normally, system power is supplied to load through STS (Static Transfer Switch), and PCS is connected to system in parallel to perform demand management. In order to efficiently operate the electric power through demand forecasting, the EMS issues a charge / discharge command to the ESS as a PMS (Power Management System), and the PMS transmits the command to the PCS controller to operate the system. During the power outage, the STS is rapidly disengaged from the system, and the PCS becomes an independent power supply and can supply constant voltage / constant frequency power to the load side. Therefore, it is possible to secure reliability through verification of actual system linkage and independent operation performance of hybrid ESS, By enabling low-carbon green growth technology to operate in conjunction with an efficient grid, it is possible to improve irregular power quality and contribute to peak load by generating renewable energy through ESS linkage. In addition, the ESS is replacing the frequency follow-up reserve, which is currently under the charge of coal-fired power generation, and thus it is anticipated that the operation cost of the LNG generator with high fuel cost can be reduced.

• The Journal of the Korea Contents Association
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• v.21 no.10
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• pp.550-563
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• 2021

This study recognizes that the externalizing problem behaviors of child with disabilities are the result of the social interaction between mother and child, and empirically verifies its systematic causal structure and multidimensional influence relationship. It was attempted to derive practical implications that can help the smooth normalization process of children's families. Therefore, 135 children with disabilities and their mothers selected by convenience sampling were targeted, and in the relationship between maternal overprotective parenting and externalizing behaviors of child, effortful control was used as a mediating variable, and defense style of mothers and children was used as a moderating variable. A Conditional Process Analysis(CPA) that can verify the moderated mediation Effect was performed by establishing a research model. As a result of the analysis, first, the overprotective parenting behavior of mother was statistically significant in both direct and indirect effects in increasing externalizing behaviors of child, and the mediation effect by effortful control was also statistically significant. Second, it was confirmed that the moderated mediation effect of effortful control by the mother's defense style was statistically significant, and the moderated mediation effect of effortful control by the child's defense style was not statistically significant. Based on the above results, assuming the importance of the influence of maternal parenting, a direct strategy for change in maternal overprotective parenting, child's Practical implications of parallel strategies with the tendency toward effective control and suboptimal strategies through the application of mothers' coping strategies were discussed.

• Journal of Korean Medicine for Obesity Research
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• v.20 no.2
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• pp.138-148
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• 2020

Objectives: The aim of this study is to evaluate the effects of Bangpungtongseong-san (Fangfengtongsheng-san, BTS) and Daesiho-tang (Dachaihu-tang, DST) on weight loss and improvement in lipid metabolism and glucose metabolism. Furthermore, we intend to develop a prediction model for drug effects through the analysis of the single nucleotide polymorphism (SNP), gut-microbiota, and the expression of immune-related biomarkers. Methods: This study is a single-center, randomized, double-blind, parallel-design clinical trial. One hundred twenty-eight participants will be assigned to the BTS group (n=64) and DST group (n=64). Both groups will be administered 4 g medication three times a day for up to 2 weeks. The primary outcomes is weight loss. The secondary outcomes include bioelectrical impedance analysis, waist circumstance, body mass index, total cholesterol, high-density lipoprotein, triglyceride, insulin resistance. The exploratory outcomes include 3-day dietary recall, food frequency questionnaire, quality of life questionnaire, gut microbiota analysis, immune biomarkers analysis, and SNP analysis. Assessment will be made at baseline and at week 4, 8, and 12. Conclusions: This protocol will be implemented by approval of the Institutional Review Board of Dongguk University. The results of this trial will provide a systematic evidence for the treatment of obesity and enable more precise herbal medicine prescriptions.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.12
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• pp.192-199
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• 2020

The blower erosion phenomenon was investigated to develop a long-life blower with a volume flow rate of 10,000 ㎥/min with the required total pressure efficiency of 83% or more. The blower performance and blower erosion were predicted through numerical analysis by computational fluid dynamics(CFD). The conditions used for numerical analysis were an air volume of 16,200 ㎥/min, a rotation speed of 893 rpm, and a temperature of 330℃. The specific gravity, particle size, and amount of the dust was 3.15, 90 ㎛~212 ㎛, and is 265 kg/min, respectively. To examine the effects of a dust deflector on erosion, erosion analysis was performed by comparing the models with and without a dust deflector. Numerical analysis showed that when the dust deflector is installed, the average tended to decrease by 167% in the impeller and 133% in the boss. CFD using the Finne's model for erosion revealed a parallel restitution coefficient of 1 and a perpendicular restitution coefficient of 0.1. The blower performance of case 5 was 691.7 mmAq, and the efficiency was 83.3% when the rotation speed and the air volume flow rate were 880 rpm and 16,200 ㎥/min, respectively.