• Korean Journal of Environment and Ecology
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• v.36 no.1
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• pp.87-101
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• 2022

This study analyzed changes in the vegetation structure of 16 permanent plots (experimental and control) installed in Wando Arboretum in 1996 to monitor the long-term change process of evergreen broad-leaved forests in warm temperate. Especially, this study discusses the effects of trial treatment (selection cutting and plant introduction), introduced as a restoration technique in 1996, on vegetation development. In communities dominated by Quercus acuta in the canopy (permanent plots 1 through 3), this species's mean important percentage (MIP) decreased, and the evergreen broad-leaved species was introduced from outside increased, likely to change the vegetation structure in the future. The expansion of the evergreen broad-leaved species group was also confirmed in Q. acuta-deciduous broad-leaved forests (permanent plots 5 and 7) and Pinus densifloraforests (permanent plots 9 and 10). In the experimental plots where thinning was carried out, the zoochory (the dispersal of seeds by birds), Cinnamomum yabunikkei, Neolitsea sericea, Machilus thunbergii, etc., and the expansion of the influence of evergreen broad-leaved species were remarkable, so it is considered to have effectively promoted the vegetation development in warm temperate forests. Although evergreen broad-leaved species were planted in the experimental plot to change vegetation structure, it seems the effect on the change was weak due to the small amount of planting. Compared to other vegetation types, the change in the vegetative structure of the pine forest to an evergreen broad-leaved forest was clear due to the decline of P. densiflora and P. thunbergii.

• International Journal of Computer Science & Network Security
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• v.21 no.11
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• pp.345-353
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• 2021

Cloud computing represent a new era of computing that's forms through the combination of service-oriented architecture (SOA), Internet and grid computing with virtualization technology. Virtualization is a concept through which every cloud is enable to provide on-demand services to the users. Most IT service provider adopt cloud based services for their users to meet the high demand of computation, as it is most flexible, reliable and scalable technology. Energy based performance tradeoff become the main challenge in cloud computing, as its acceptance and popularity increases day by day. Cloud data centers required a huge amount of power supply to the virtualization of servers for maintain on- demand high computing. High power demand increase the energy cost of service providers as well as it also harm the environment through the emission of CO₂. An optimization of cloud computing based on energy-performance tradeoff is required to obtain the balance between energy saving and QoS (quality of services) policies of cloud. A study about power usage of resources in cloud data centers based on workload assign to them, says that an idle server consume near about 50% of its peak utilization power [1]. Therefore, more number of underutilized servers in any cloud data center is responsible to reduce the energy performance tradeoff. To handle this issue, a lots of research proposed as energy efficient algorithms for minimize the consumption of energy and also maintain the SLA (service level agreement) at a satisfactory level. VM (virtual machine) consolidation is one such technique that ensured about the balance of energy based SLA. In the scope of this paper, we explore reinforcement with fuzzy logic (RFL) for VM consolidation to achieve energy based SLA. In this proposed RFL based active VM consolidation, the primary objective is to manage physical server (PS) nodes in order to avoid over-utilized and under-utilized, and to optimize the placement of VMs. A dynamic threshold (based on RFL) is proposed for over-utilized PS detection. For over-utilized PS, a VM selection policy based on fuzzy logic is proposed, which selects VM for migration to maintain the balance of SLA. Additionally, it incorporate VM placement policy through categorization of non-overutilized servers as- balanced, under-utilized and critical. CloudSim toolkit is used to simulate the proposed work on real-world work load traces of CoMon Project define by PlanetLab. Simulation results shows that the proposed policies is most energy efficient compared to others in terms of reduction in both electricity usage and SLA violation.

• Journal of Korean Tunnelling and Underground Space Association
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• v.25 no.3
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• pp.201-220
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• 2023

Power cable tunnels is one of the underground structures meant for electricity transmission and are constructed using shield TBM method when transitting across urban and subsea regions. With the increasing shaft depth for tunnels excavation when the shield TBM excavated the rock mass, the review of selecting closed-type shield TBM in rocks becomes necessary. A simplified shield TBM design method is also necessary based on conventional geotechnical survey results. In this respect, design method and related design program are developed based on combined results of full-scale tests, considerable amount of accumulated TBM data, and numerical simulation results. In order to validate the program results, excavation data of a completed power cable tunnel project are utilized. Thrust force, torque, and power of shield TBM specification are validated using Kernel density concept which estimates the population data. The robustness of design expertise is established through this research which will help in stable provision of electricity supply.

• Korean Journal of Construction Engineering and Management
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• v.24 no.5
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• pp.44-51
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• 2023

Selecting appropriate bidding system in construction projects considering the characteristic of project can be a make-or-break element, so the understanding for bidding system of public construction projects is ever more important from the perspective of both the owner and the contractor. The design-build bidding is commonly referred to as turnkey in Korea, and is a bidding method that is often applied to large public construction projects because it allows new technologies to be applied to the design and facilitates risk management for the owner. In this bidding method, there are only two factors (design score and price score) that affect the selection of the winning bidder, so it is important to understand the influence of each factor, but there is little research on the subject. This study aims to provide a basis for establishing bidding strategies for understanding the influence between design score and price score by analyzing various design-build bidding data of public construction projects. The results of the study show that design score is the factor that has more influence on the ranking of bidders in all three weighted evaluation methods: design-emphasized, price-emphasized, and equalized evaluation. In addition, we found that the correlation between design and price scores was not significant due to the unique bid evaluation structure in Korea.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.33 no.2
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• pp.247-264
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• 2023

Objectives: The study was to examine the features of three-dimensional(3D) face dimensions and to develop fit test panels for the labor population using respirators in South Korea. Methods: This study was part of the first-year work of a two-year-project conducted at Occupational Safety and Health Research Institute in 2021. After 3D head dimensions data were collected from Size Korea Center managing Sixth Size Korea databases, 3D face dimensions DB for the South Korean labor population was established for 21 items of face dimensions in line with the ISO/TS 16976-2 and KS A ISO 15535. With the South Korean labor population 3D face dimensions DB, in accordance with the ISO/TS 16976-2, the descriptive statistics of 3D face dimensions were calculated and two fit test panels were developed. Results: A total of 2,752 subjects were finally determined and they were 52.9% for male, 41.2% for the highest age-group of 15-29, and residents in the capital area. Mean and standard deviation were obtained for each of the 21 3D face dimensions items for the South Korean labor population. Among the items, male and female face widths were 137.6±5.7 mm, 133.2±5.0 mm, respectively. Male and female face lengths were 116.6±7.0 mm, 107.8±6.8 mm, respectively. Two new South Korean fit test panels, a bivariate test panel and a principal component analysis test panel, were developed using the 3D face dimensions DB as well. Conclusions: Using the 3D face dimensions DB, the mean and standard deviation were featured for each of the 21 items and also the two fit test panels were newly developed in the study. It is suggested that the study outputs should be utilized practically and effectively in selection, use, and management of respirators at work, expecting that respiratory protection can be furthermore improved for respirator users including labor population across the country.

• Journal of the Korean Institute of Landscape Architecture
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• v.51 no.5
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• pp.70-83
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• 2023

Recently, the Korea Forest Service has implemented a planning project about wind corridor forests as a response measure to climate change. Based on this, research on wind corridors has been underway. For the creation of wind corridor forests, a preliminary evaluation of the wind corridor function is necessary. However, currently, there is no evaluation index to directly evaluate and spatially distinguish the types of wind corridors, and analysis is being performed based on indirect indicators. Therefore, this study proposed a method to evaluate and classify wind corridors by utilizing heat deficit analysis as an evaluation index for cold air generation. Heat deficit was analyzed using a cold air analysis model called Kaltluftabflussmodell_21 (KLAM_21). According to the results of the simulation analysis, the wind path was functionally classified. The top 5% were classified as cold-air generating Areas (CGA), and the bottom 5% as cold-air vulnerable Areas (CVA). In addition, the cold-air flowing Areas (CFA) were classified by identifying the flow of cold air moving from the cold air generation area. It is expected that the methodology of this study can be utilized as an evaluation method for the effectiveness of wind corridors. It is also anticipated to be used as an evaluation index to be presented in the selection of wind corridor forest sites.

• Tunnel and Underground Space
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• v.33 no.5
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• pp.348-372
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• 2023

In relation to the high-level radioactive waste disposal project in deep fractured rock aquifer environments, it is essential to evaluate hydrogeological characteristics for evaluating the suitability of the site and operational stability. Such subsurface hydrogeological data is obtained through in-situ tests using boreholes excavated at the target site. The accuracy and reliability of the investigation results are directly related to the selection of appropriate test methods, the performance of the investigation system, standardization of the investigation procedure. In this report, we introduce the detailed procedures for the representative test method, the constant pressure injection test (CPIT), which is used to determine the key hydrogeological parameters of the subsurface fractured rock aquifer, namely hydraulic conductivity and storativity. This report further refines the standard test method suggested by the KSRM in 2022 and includes practical field application case conducted in volcanic rock aquifers where this investigation procedure has been applied.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.18 no.5
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• pp.159-174
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• 2023

In this paper, we proposed a methodology to effectively determine the selection and prioritization of new business and innovation projects using AI technology. AI technology is a technology that can upgrade the business of companies in various industries and increase the added value of the entire industry. However, there are various constraints and difficulties in the decision-making process of selecting and implementing AI projects in the enterprise. In this paper, we propose a new methodology for prioritizing AI projects using Morphology, AHP, and TOPSIS. The proposed methodology helps prioritize AI projects by simultaneously considering the technical feasibility of AI technology and real-world user requirements. In this study, we applied the proposal methodology to a real enterprise that wanted to prioritize multiple AI projects in the HR field and evaluated the results. The results confirm the practical applicability of the methodology and suggest ways to use it to help companies make decisions about AI projects. The significance of the methodology proposed in this study is that it is a framework for prioritizing multiple AI projects considered by a company in the most reasonable way by considering both business and technical factors at the same time.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.15 no.4
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• pp.135-149
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• 2020

As youth employment has become a social issue every year, the government is pushing for policies to support youth start-ups to create jobs voluntarily as a way to enhance the youth employment rate. In the case of young people in Gangwon Province, the number of people moving to other regions is increasing. This research is intended to empirically analyze the actual achievements of youth start-ups through the 'Youth Start-up Project' in Gangwon-do. It was divided into four categories: participation in government support, education completion, intellectual property right retention, and certification retention, which are characteristics of start-up companies, and hypotheses that they will have a positive impact on start-up performance (sales amount, duration of existence, or whether they are retained or not). Age and geographical factors (Yeongdong and Yeongseo) were injected as control variables to see how they affect them. Furthermore, empirical analysis was conducted by setting up a hypothesis that the characteristics of start-up companies and subsequent support between start-up performance would have a positive intermediary effect. The research results showed that the remaining characteristics, except for education completion, had a positive impact on sales, and that the more participation in government projects, the longer the duration of the company's existence. In addition, the level of participation in government support projects was significant in the direction of the government. The analysis results of the parameter, follow-up support, had a positive impact on the start-up performance, and the subsequent support mediating effect showed the mediating effect of the start-up performance, except for geographical factors. The results of this study suggest the need for customized support suitable for the characteristics of youth start-ups in order to enhance the performance of young start-ups. Support agencies need to refer to corporate characteristics for smooth management and selection. In the Gangwon-do area, the government should seek to provide timely and organic support for start-up companies in order to produce successful start-up cases.

• Journal of Food Hygiene and Safety
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• v.23 no.1
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• pp.31-39
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• 2008

This study was performed to develop children's food quality certification system as part of the children's favorite foods safety management projects. As a component of the research, we developed a quality certification logo to build up brand image which is familiar with children, as well as to offer the right standard and opportunity for food selection. The age level contains elementary graders from 8 to 13. The logo concept was focused on 'Safety', 'Certification, Guidance' and 'Health' in accordance with the vision of the Korea Food and Drug Administration (KFDA), "Safe food, good nutrition and healthy children". The logo name was proposed as "Best Food for Children", "Safety Food for Children" and "Children Good Food", which was decided by public subscription in the KFDA. The 36 tentative plans for a seal were proposed depending on names. We conducted a survey for the 12 logo samples, designed by the name of "Children Good Food", to use as the basic material for the development of logo to convey the meaning of children's food quality certification system effectively. This survey was conducted among 321 elementary graders and 331 parents of elementary graders. We selected the most favorite design through the survey and applied it for products practicality. It is expected that a steady policy may be possible to implement by applying the basis of the children's food project.