• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.23 no.4
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• pp.189-196
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• 2023

As the manufacturing paradigm shifts, various collaborative robots are creating new markets. Demand for collaborative robots is increasing in all industries for the purpose of easy operation, productivity improvement, and replacement of manpower who do simple tasks compared to existing industrial robots. However, accidents frequently occur during work caused by collaborative robots in industrial sites, threatening the safety of workers. In order to construct an industrial site through robots in a human-centered environment, the safety of workers must be guaranteed, and there is a need to develop a collaborative robot guard system that provides reliable communication without the possibility of dispatch. It is necessary to double prevent accidents that occur within the working radius of cobots and reduce the risk of safety accidents through sensors and computer vision. We build a system based on OPC UA, an international protocol for communication with various industrial equipment, and propose a collaborative robot guard system through image analysis using ultrasonic sensors and CNN (Convolution Neural Network). The proposed system evaluates the possibility of robot control in an unsafe situation for a worker.

• Journal of Advanced Navigation Technology
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• v.27 no.4
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• pp.382-390
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• 2023

The Korea market for LUAV (Light Unmanned Aerial Vehicle) weighing less than 150 kg is growing rapidly. As a result, the market for manufacturing and operating LUAV is expanding, and domestic development of parts and finished products is actively taking place. However, the flight control system and onboard software, which are key components of domestic LUAV, are largely dependent on overseas products due to the excessive cost and period required for development. This paper presented a domestic software development and certification procedure using DO-178C, a guideline for aircraft software development, and the Model-based Development method, and conducted a survey of those involved in the development, manufacturing, and certification of LUAV and analyzed the results. In addition, a case study was conducted to apply the software development plan to the helicopter FCC (Flight Control Computer).

• The Journal of the Convergence on Culture Technology
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• v.9 no.1
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• pp.649-654
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• 2023

This paper proposes the design of a neural network structure search model using graph convolutional neural networks. Deep learning has a problem of not being able to verify whether the designed model has a structure with optimized performance due to the nature of learning as a black box. The neural network structure search model is composed of a recurrent neural network that creates a model and a convolutional neural network that is the generated network. Conventional neural network structure search models use recurrent neural networks, but in this paper, we propose GC-NAS, which uses graph convolutional neural networks instead of recurrent neural networks to create convolutional neural network models. The proposed GC-NAS uses the Layer Extraction Block to explore depth, and the Hyper Parameter Prediction Block to explore spatial and temporal information (hyper parameters) based on depth information in parallel. Therefore, since the depth information is reflected, the search area is wider, and the purpose of the search area of the model is clear by conducting a parallel search with depth information, so it is judged to be superior in theoretical structure compared to GC-NAS. GC-NAS is expected to solve the problem of the high-dimensional time axis and the range of spatial search of recurrent neural networks in the existing neural network structure search model through the graph convolutional neural network block and graph generation algorithm. In addition, we hope that the GC-NAS proposed in this paper will serve as an opportunity for active research on the application of graph convolutional neural networks to neural network structure search.

• Journal of the Korea Institute of Building Construction
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• v.23 no.2
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• pp.175-185
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• 2023

Upon analyzing labor productivity in the construction industry across OECD countries, it was found that in 2019, labor productivity per employee in the South Korean construction industry was lower than that of major developed countries when adjusted for purchasing power parity(PPP). Specifically, when benchmarked against other countries at a base of 100, South Korea scored 76.9 in the United States, 88.4 in Japan, and 85.1 in the OECD average. Notably, South Korea ranked 25th in labor productivity per employee in the construction industry among 35 OECD countries in 2019, indicating a low standing. A comparative analysis of the construction market size and labor productivity in the construction industry across OECD countries revealed that larger construction markets did not necessarily correlate with higher labor productivity. To enhance labor productivity in the construction industry, this study proposed the active implementation of smart construction technology at construction sites and the promotion of on-site assembly work using off-site construction(OSC) technology, rather than traditional on-site labor. Moreover, it was recommended that the development of modular construction methods and technologies be expanded. In the future, if off-site production methods and modules are further developed through advanced robotics and factory automation, labor productivity is anticipated to increase due to the restructuring of production methods, such as manufacturing.

• Korean Journal of Environment and Ecology
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• v.36 no.6
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• pp.662-675
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• 2022

This study was intended to investigate and analyze the current status of the plant community structure in order to provide basic data for the systematic conservation and management of the Buxus sinica area appearing on the ridgeline connecting the Gyeokjabong(Mt.) and Keungiljae, on Bogildo Island. In consideration of location characteristics such as density, topography, and direction of B. sinica appearing in the shrub layers, a total of 26 sites were set as the survey area for representative vegetation communities or areas with changes in topography. According to DCA and TWINSPAN, it was classified into 6 communities, namely Carpinus turczaninovii-Deciduous broad-leaved, C. turczaninovii, C. turczaninovii-B. sinica, C. turczaninovii-Evergreen broad-leaved, Q. acuta, and D. trifidus-Q. acuta. The community dominated by C. turczaninovii maintains the status quo for the present moment, however, Q. acuta will dominate the surrounding area in the long term, so Q. acuta has high succesion potential. In the case of the Q. acuta and D. trifidus-Q. acuta communities, Q. acuta, known as the climax species of warm-temperate forests, will maintain dominant status. In a case of B. sinica, the community dominated by C. turczaninovii will remain in good status due to the topographical conditions, but the community dominated by Q. acuta growth difficulties are expected due to the high coverage. In the relationship between environmental factors and vegetation distribution, analysis showed that only soil pH affect vegetation distribution. Furthermore, the soil acidity (pH) was 3.78-5.30, the electrical conductivity was 0.186-0.543 dS/m, and the organic matter content was 2.25-2.89%.

• Composites Research
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• v.20 no.5
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• pp.64-69
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• 2007

Matrix dominant properties of composites are largely degraded under harmful environments such as temperature and humidity. Therefore we should consider the harmful environmental factors in the design of an UAV integral fuel tank subjected to high temperature and high humidity. The harmful environment experiment was performed for carbon/epoxy composites made of a unidirectional prepreg USN175B, and a plain woven fabric prepreg WSN3. The immersion experiment was performed under $90^{\circ}C$. The specimens were tested when the weight gam of specimen was saturated. The specimens were tested under $74^{\circ}C$ to obtain tensile and inplane shear properties. The results showed that the matrix dominant properties were extremely degraded by hygrothermal environment. To consider the variability of load, the anti-optimization method was applied. By using this method, the worst load case was found by comparing the load convex model and stability boundary. The stability boundary was obtained by analysis of the integral wing fuel tank of UAV using degraded properties. To do this, it was known that the worst load case of the integral wing fuel tank was the hovering mode load case.

• The Journal of the Korea institute of electronic communication sciences
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• v.17 no.2
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• pp.265-278
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• 2022

The global energy paradigm is rapidly changing by centering on carbon neutrality, and wind energy is positioning itself as a leader in renewable energy-based power sources. The success of onshore and offshore wind energy projects focuses on securing the economic feasibility of the project, which depends on securing high-quality wind resources and optimal arrangement of wind turbines. In the process of constructing the wind farm, the optimal arrangement method of wind turbines considering the main wind direction is important, and this is related to minimizing the wake effect caused by the fluid passing through the structure located on the windward side. The accuracy of the predictability of the wake effect is determined by the wake model and modeling technique that can properly simulate it. Therefore, in this paper, using WindSim, a commercial CFD model, the wake diffusion pattern is analyzed through the sensitivity study of each wake model of the proposed onshore wind farm located in the mountainous complex terrain in South Korea, and it is intended to be used as basic research data for wind energy projects in complex terrain in the future.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.7 no.1
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• pp.395-405
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• 2017

To confirm potential anti-cancer activities of ethylacetate (EtOAc) fraction from Orostachys japonicus on the A549 human lung cancer cells, this study examined. As a result of conducting MTS assay for measuring cell viability, the EtOAc fraction inhibited the proliferation of A549 cells in a dose-dependent manner. To investigate whether the inhibiting A549 cell viability was caused by apoptosis, this study analyzed chromatin condensation in A549 cells using DAPI staining. The morphological changes such as the formation of nuclear condensation were formed in a dose-dependent manner. Also, this study performed Annexin V-FITC staining for detecting phosphatidylinositol (PS). As a result of Annexin V-FITC staining to investigate level of early and late apoptosis, the apoptosis level treated with EtOAc fraction was higher than that of control. RT-PCR was performed to study the correlation between G2/M cell cycle arrest and cell cycle control genes. The anti-cancer activity of EtOAc fraction was accompanied by inhibition of CDK1, 4, cyclin B1 and D1 mRNA. This study also examined the expression of various marker proteins: p53, Bax, Bcl-2 and pro-caspase 3. Western blotting revealed that p53 and Bax proteins were up-regulated, and Bcl-2 and pro-caspase 3 proteins down-regulated in a time and dose-dependent manner.

• The Korean Journal of Franchise Management
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• v.9 no.1
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• pp.41-51
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• 2018

Purpose - In franchise system, how to build the relationship between the franchisor and franchisee through influence strategy is very important, because it affects on the long-term orientation like recontract intentions. Thus, this study examines the effect of mandatory influence strategy on relationship satisfaction, relationship trust, and recontract intentions in the context of food-service franchise industry. This study suggests the guidelines on how franchisor uses their influence strategy on franchisee to maintain and increase the recontract intentions. Research design, data, and methodology - This study examines the structural relationship between mandatory influence strategy, relationship satisfaction, relationship trust, and recontract intentions from the franchisee's perspective. Mandatory influence strategy divide into three sub-dimensions such as request, legalistic plea, threat. In order to test the purposes of this study, research model and hypotheses were developed. Every constructs were measured by multiple items tested and developed in the previous research. Also, the constructs utilized in this research are measured using 7-point scales anchored by "1=strongly disagree" and 7=strongly agree". The data were collected from 496 owner and owner manager franchisees and were analyzed using SPSS 21.0 and Smart PLS 3.0. program. Analysis of frequency was conducted to identify the demographics and general characteristics of the survey subjects. In order to measure the reliability and validity of the measurement tools, confirmatory factor analysis and correlation analysis were conducted and structural model analysis was conducted to verify the proposed research model. Result - The results of this study are as follows. First, this research found that mandatory influence strategy is positively related to relationship satisfaction and relationship trust, but not to recontract intention directly. Second, this research also found that the full mediating role of relationship satisfaction and relationship trust between the mandatory influence strategy and recontract intention. Conclusions - The findings of this research indicate that franchisor should use properly mandatory influence strategy to improve recontract intentions through relationship satisfaction and relationship trust. Due to the nature of food-service franchise industry, which needs high relationship quality, franchisor must manage their franchisee using influence strategy in order to improve satisfaction and trust. If franchisee perceives higher relationship quality, they will show higher intention to recontract. At the end of this paper, limitations and future research directions were suggested.

• The Korean Journal of Franchise Management
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• v.8 no.4
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• pp.21-32
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• 2017

Purpose - In hotel business, how to build the relationship between leader and employees is very important, because it affects on the customer satisfaction. Thus, this research examines the effect of authentic leadership on job performance in the context of hotel industry and identifies mediating roles of organizational engagement, job satisfaction, and creativity in the relationship between authentic leadership and job performance. This study suggests the guidelines for how hotel companies should improve employee productivity and build a desirable organizational culture by presenting employee attitudes and behavioral models that explain the relationship between leaders and employees. Research design, data, and methodology - This study examines the structural relationship between authentic leadership, organizational engagement, job satisfaction, creativity, and job performance from the employee's perspective. Authentic leadership divide into four sub-dimensions such as self-awareness, balanced process of informations, internalized moral perspective, and relational transparency. In order to test the purposes of this study, research model and hypotheses were developed. All constructs were measured with multiple items developed and tested in the previous studies. The data were collected from 114 franchise hotel employees and were analyzed using SPSS 21.0 and Smart PLS 3.0. program. Result - The results of this study are as follows. First, authentic leadership have significant impacts on organizational engagement and creativity, but does not have impact on job satisfaction directly. Second, organizational engagement have significant impacts on job satisfaction and job performance, but does not have impact on creativity directly. Third, job satisfaction has significant impact on creativity, but does not have impact on job performance. Fourth, creativity has significant impact on job performance. Conclusions - The findings of this study indicate that hotel leaders should properly implement the authentic leadership and consider how to build a corporate culture to improve an organizational and employee productivity through authentic leadership. Due to the nature of the hotel industry, which relies heavily on human resources, hotel companies must manage their employees with authenticity in order to increase organizational engagement, job satisfaction, and creativity that affect hotel and employee productivity. If hotel employees perceive their leader's authentic leadership, they show more organizational engagement that increases creativity and leads to job performance. Finally, hotel employees can propose creative ideas only if they will be satisfied with their jobs. Therefore, the leader should develop non-monetary or monetary reward system for the employees and, make an efforts to foster creativity of the employees.