• Title/Summary/Keyword: Complex System

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Effect Analysis of Offshore Wind Farms on VHF band Communications (VHF 대역 통신에 대한 해상풍력 발전단지의 영향성 분석)

  • Oh, Seongwon;Park, Taeyong
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.28 no.2
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    • pp.307-313
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    • 2022
  • As the development of renewable energy expands internationally to cope with global warming and climate change, the share of wind power generation has been gradually increasing. Although wind farms can produce electric power for 24 h a day compared to solar power plants, Their interfere with the operation of nearby radars or communication equipment must be analyzed because large-scale wind power turbines are installed. This study analyzed whether a land radio station can receive sufficient signals when a ship sailing outside the offshore wind farm transmits distress signals on the VHF band. Based on the geographic information system digital map around the target area, wind turbine CAD model, and wind farm layout, the area of interest and wind farm were modeled to enable numerical analysis. Among the high frequency analysis techniques suitable for radio wave analysis in a wide area, a dedicated program applying physical optics (PO) and shooting and bouncing ray (SBR) techniques were used. Consequently, the land radio station could receive the electromagnetic field above the threshold of the VHF receiver when a ship outside the offshore wind farm transmitted a distress communication signal. When the line of sight between the ships and the land station are completely blocked, the strength of the received field decreases, but it is still above the threshold. Hence, although a wind farm is a huge complex, a land station can receive the electromagnetic field from the ship's VHF transmitter because the wave length of the VHF band is sufficiently long to have effects such as diffraction or reflection.

Anti-atopic dermatitis effects of Parasenecio auriculatus via simultaneous inhibition of multiple inflammatory pathways

  • Kwon, Yujin;Cho, Su-Yeon;Kwon, Jaeyoung;Hwang, Min;Hwang, Hoseong;Kang, Yoon Jin;Lee, Hyeon-Seong;Kim, Jiyoon;Kim, Won Kyu
    • BMB Reports
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    • v.55 no.6
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    • pp.275-280
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    • 2022
  • The treatment of atopic dermatitis (AD) is challenging due to its complex etiology. From epidermal disruption to chronic inflammation, various cells and inflammatory pathways contribute to the progression of AD. As with immunosuppressants, general inhibition of inflammatory pathways can be effective, but this approach is not suitable for long-term treatment due to its side effects. This study aimed to identify a plant extract (PE) with anti-inflammatory effects on multiple cell types involved in AD development and provide relevant mechanistic evidence. Degranulation was measured in RBL-2H3 cells to screen 30 PEs native to South Korea. To investigate the anti-inflammatory effects of Parasenecio auriculatus var. matsumurana Nakai extract (PAE) in AD, production of cytokines and nitric oxide, activation status of FcεRI and TLR4 signaling, cell-cell junction, and cell viability were evaluated using qRT-PCR, western blotting, confocal microscopy, Griess system, and an MTT assay in RBL-2H3, HEK293, RAW264.7, and HaCaT cells. For in vivo experiments, a DNCBinduced AD mouse model was constructed, and hematoxylin and eosin, periodic acid-Schiff, toluidine blue, and F4/80-staining were performed. The chemical constituents of PAE were analyzed by HPLC-MS. By measuring the anti-degranulation effects of 30 PEs in RBL-2H3 cells, we found that Paeonia lactiflora Pall., PA, and Rehmannia glutinosa (Gaertn.) Libosch. ex Steud. show an inhibitory activity of more than 50%. Of these, PAE most dramatically and consistently suppressed cytokine expression, including IL-4, IL-9, IL-13, and TNF-α. PAE potently inhibited FcεRI signaling, which mechanistically supports its basophil-stabilizing effects, and PAE downregulated cytokines and NO production in macrophages via perturbation of toll-like receptor signaling. Moreover, PAE suppressed cytokine production in keratinocytes and upregulated the expression of tight junction molecules ZO-1 and occludin. In a DNCB-induced AD mouse model, the topical application of PAE significantly improved atopic index scores, immune cell infiltration, cytokine expression, abnormal activation of signaling molecules in FcεRI and TLR signaling, and damaged skin structure compared with dexamethasone. The anti-inflammatory effect of PAE was mainly due to integerrimine. Our findings suggest that PAE could potently inhibit multi-inflammatory cells involved in AD development, synergistically block the propagation of inflammatory responses, and thus alleviate AD symptoms.

Development of evaluation index for value creation of blockchain adoption in real estate electronic transaction system - Based on AHP analysis - (부동산 전자거래시스템 내 블록체인 도입의 가치창출 평가지표 개발 - AHP 분석 기법을 기반으로 -)

  • Lee, Sungmin;Kim, Heejoon;Lee, Myeonghun;Kim, Jaejun
    • Korean Journal of Construction Engineering and Management
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    • v.23 no.3
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    • pp.74-82
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    • 2022
  • With the introduction of proptech, this study aims to find out the changes and necessity of introducing blockchain technology, one of the most popular technologies, in real estate electronic transactions. In addition, it is intended to develop evaluation indicators that classify newly created values within real estate electronic transactions and calculate the relative importance of each value area through technology application. To this end, the value that can be created when applying blockchain technology to real estate electronic transactions was classified according to the hierarchy, and considering that the evaluation criteria are complex and the importance can be measured differently depending on various factors, an analysis was conducted according to the AHP method for experts in practical and academic fields. As a result of the analysis, general value showed the highest importance in the first dimension, and digitalization of real estate information showed the highest importance in the second dimension.

A Study on Perceptions of Users and Specialists for Establishing Mid-to Long Term Development Plan for Libraries in Anyang City (안양시 도서관 중장기 계획 수립을 위한 이용자 및 전문가 인식 연구)

  • Song, Min Sun;Chang, Inho;Hoang, Gum-Sook
    • Journal of the Korean Society for Library and Information Science
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    • v.56 no.1
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    • pp.67-93
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    • 2022
  • This study purposes for the based data for establishing the mid- to long term development direction of Anyang municipal libraries by conducting a survey of residents in Anyang city and focus group interviews with local experts. Based on the results of the survey and FGI analysis conducted in this study, the main implications and discussions for establishing mid- to long term development plans for Anyang municipal libraries in the future are summarized as follows. First, the services used by users are extremely limited compared to the utilization rate of library, and the utilization rate of library programs is low, therefore Anyang municipal libraries need to actively promote various services operated by the library, provide information, and make efforts to improve service use procedures simply. Second, library satisfaction is relatively high, but as a result of analyzing the reasons for some dissatisfaction, active budget investment for purchasing new library materials and ways to increase library accessibility are necessary. Third, due to the low awareness of the operation of specialized libraries, it is necessary to develop specialized, unique library services to Anyang municipal libraries through benchmarking of other best practices. Fourth, in the future, Anyang municipal libraries need to strengthen functions as a complex cultural center along with the functions as an information center, a lifelong education center, and a living convenience center. Lastly, it is required to construct a control tower that can systematically lead the operation of Anyang municipal libraries in the long term through the reorganization of the organizational system.

Consideration of Procurement System and Material Homogeneity for Lime and Clay using the Tombs within the King Muryeong and the Royal Tombs in Gongju, Korea (공주 무령왕릉과 왕릉원 내부에 사용한 석회 및 점토의 재료학적 동질성과 조달체계 검토)

  • Choi, Il Kyu;Yang, Hye Ri;Lee, Chan Hee
    • Economic and Environmental Geology
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    • v.55 no.5
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    • pp.447-463
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    • 2022
  • The lime and clay that used in the construction of the Tomb of King Muryeong and the Royal Tombs in Gongju are auxiliary materials, and are used joint and plaster materials for the wall to play a role of structural support. In this study, the homogeneity between the tombs and material characteristics were interpreted through quantitative analysis of lime and clay. As a result of microtexture and composition analysis, almost the same minerals were identified in each sample groups, and similar characteristics were shown in thermal analysis. Geochemically, it is confirmed that the behavior characteristics are very similar regardless of the tombs. The compositions is also confirmed high homogeneity in the diagrams of CaO-MgO-SiO2, RO2-(RO+R2O) correlations, A-CN-K and A-CNK-FM triangles. Therefore, it is interpreted that the clay used for the construction of the tomb complex was supplied from around area, and the raw materials of lime were produced using shell fragments of oyster family based on mainly composed of calcite. It is interpreted that the raw materials of lime were supplied from middens along the west coast of down the Geumgang river in Korean peninsula, but the consideration of the supply site, needs to be cross-validated through stable isotope analysis, use of carbonate rock and reproduction experiments.

A Phenomenological Study on the Burnout of Specialized Counselors in the 117 Report Center - Application of the Integrated Working System of Government Departments- (117 신고센터 전문상담 요원의 소진에 관한 현상학적 연구 -정부 부처 통합근무 체제 적용-)

  • Youn, Yang-suk;Kim, Eun-hye
    • Industry Promotion Research
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    • v.7 no.3
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    • pp.85-91
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    • 2022
  • In modern society, the field of life is expanding to complex and diverse fields according to changes in lifestyle. As people's consciousness also changes, various social problems are involved, and countermeasures are being taken in various ways. In particular, as the issue of school violence has become a subject of interest, government-related ministries have jointly set up a reporting center and professional counselors are receiving and consulting on damage reports. Counselors experience mental and physical exhaustion in the course of their work. Therefore, the need to contribute to effective counseling work is raised by studying the factors that cause burnout. This study collected the experiences of 10 counselors working at 117 reporting centers from February 2019 to May 2020 through interviews and analyzed them with Colaizzi's phenomenological research method. The exhaustion factors derived from the results of the study were first experiences such as conflict between counselors during the period of institutional integration in the "117 reporting center experience", and secondly, professional counselors experienced emotional exhaustion, inhumanization, and lack of achievement. In order to prevent and overcome the exhaustion factors of counseling agents, it was necessary to prepare measures to promote fraud. This is expected to be useful data for improving the working environment of special job counselors in the era of industrialization and informatization in which various anonymous counseling methods are used.

A Study on Team Collaboration Affecting Team Performance: Mediating Effect of Team Shared Cognition, Team Transactive Memory, Team Knowledge Integration, and Team Efficacy with Focus on Consulting Projects (팀성과에 영향을 미치는 팀협업에 관한 연구: 컨설팅 프로젝트를 중심으로 팀공유인지, 팀정보교류, 팀지식통합, 팀효능감의 매개효과)

  • Chae-Sang Shin;Jung-Wan Hong
    • Journal of Industrial Convergence
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    • v.21 no.1
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    • pp.9-31
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    • 2023
  • This study is a study on the different cognitive systems and different knowledge systems of members participating in complex and diverse consulting projects, and it is a study on team collaboration that affects the team performance of the project. The purpose of this study is to analyze the mediating effects of team shared cognition, team transactive memory, team knowledge integration, and team efficacy in the cognitive interaction process of a consulting project. This study established a research model and research hypothesis based on previous studies. Data were collected from consultants who actually participated in the consulting project. To empirically analyze the research hypothesis, demographic analysis, validity and reliability analysis, structural model analysis for hypothesis verification, and mediating effect analysis using phantom variables were performed. As a result of the study, in order to increase team performance, it is necessary to improve team shared cognition and team transactive memory, which are cognitive systems, and team knowledge integration, which is a knowledge system, must also be improved. Therefore, there is a need for a sense of team efficacy that integrates disparate cognitive and knowledge systems, trusts each other's expertise, and enables successful team work. In addition, future studies on sub-factors of cognitive processes are needed.

Dynamic Behavior Characteristics of Group Piles with Relative Density in Sandy Soil (건조 모래지반의 상대밀도에 따른 무리말뚝의 동적거동특성)

  • Heungtae Kim;Hongsig Kang;Kusik Jeong;Kwangkuk Ahn
    • Journal of the Korean GEO-environmental Society
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    • v.24 no.9
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    • pp.33-40
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    • 2023
  • The lateral load which is applied to the pile foundation supporting the superstructure during an earthquake is divided into the inertia force of the upper structure and the kinematic force of the ground. The inertia force and the kinematic force could cause failure to the pile foundation through different complex mechanisms. So it is necessary to predict and evaluate interaction of the ground-pile-structure properly for the seismic design of the foundation. The interaction is affected by the lateral behavior of the structure, the length of the pile, the boundary conditions of the head, and the relative density of the ground. Confining pressure and ground stiffness change accordingly when the relative density changes, and it results that the coefficient of subgrade reaction varies depending on each system. Horizontal bearing behavior and capacity of the pile foundation vary depending on lateral load condition and relative density of the sandy soil. Therefore, the 1g shaking table tests were conducted to confirm the effect of the relative density of the dried sandy soil to dynamic behavior of the group pile supporting the superstructure. The result shows that, as the relative density increases, maximum acceleration of the superstructure and the pile cap increases and decreases respectively, and the slope of the p-y curve of the pile decreases.

A Study on Implementing BSC in the Public Enterprises : The Case of Korea Southern Power (공기업의 BSC 구축에 관한 연구: 한국남부발전(주) 사례를 중심으로)

  • Suh, Woo-Jong;Park, Jin-Bae;Hong, Jin-Won
    • Journal of Korea Society of Industrial Information Systems
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    • v.14 no.4
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    • pp.163-182
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    • 2009
  • The BSC(Balanced Scorecard), a strategic performance evaluation system, has drawn attention as an innovative tool for improving an organization's performance. Recently, the Korean government has recognized the advantages of the BSC and encouraged public enterprises to implement the BSC. However, it has been pointed out that many public enterprises have faced difficulties in constructing and operating the BSC due to lack of clear understanding, a complex environment of performance evaluation, and inherent features of organizational culture. Therefore, this study analyzed a project case of a public enterprise, Korea Southern Power (KSP), which has ever been assessed as an excellent organization in implementing BSC and managing performance. This paper provides procedures, activities, resources (manpower and time), and decision-making issues and criteria required for implementing BSC, along with real project outcomes of the company. Such project details are expected to be used as helpful guidelines for public or non-profit organizations's BSC implementation. Furthermore, the KSP's efforts to cope with its problems and implications derived from the efforts are also expected to help other organizations construct and operate the BSC effectively.

High-resolution Urban Flood Modeling using Cellular Automata-based WCA2D in the Oncheon-cheon Catchment in Busan, South Korea (셀룰러 오토마타 기반 WCA2D 모형을 이용한 부산 온천천 유역 고해상도 도시 침수 해석)

  • Choi, Hyeonjin;Lee, Songhee;Woo, Hyuna;Noh, Seong Jin
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.43 no.5
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    • pp.587-599
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    • 2023
  • As climate change increasesthe frequency and risk of flooding in major cities around theworld, the importance ofsimulation technology that can quickly and accurately analyze high-resolution 2D flooding information in large-scale areasis emerging. The physically-based approaches based on the Shallow Water Equations (SWE) often requires huge computer resources hindering high-resolution flood prediction. This study investigated the theoretical background of Weighted Cellular Automata 2D (WCA2D), which simulates spatio-temporal changes offlooding using transition rules and weight-based system, and assessed feasibility to simulate pluvial flooding in the urbancatchment, theOncheon-cheon catchmentinBusan, SouthKorea.Inaddition,the computation performancewas compared by applying versions using OpenComputing Language (OpenCL) andOpenMulti-Processing (OpenMP) parallel computing techniques. Simulationresultsshowed that the maximuminundation depthmap by theWCA2Dmodel cansimilarly reproduce historical inundation maps. Also, it can precisely simulate spatio-temporal changes of flooding extent in the urban catchment with complex topographic characteristics. For computation efficiency, parallel computing schemes, theOpenCLandOpenMP, improved the computation by about 8~14 and 5~6 folds respectively, compared to the sequential computation.