• Title/Summary/Keyword: Mutual structures

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Development of a Calculation Model for an Optimal Safe Distance between Ship Routes and Offshore Wind Sites (선박 통항로와 해상풍력단지 간 최적의 이격거리 산정 모델 개발)

  • Ohn, Sung-Wook;Namgung, Ho
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.28 no.6
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    • pp.973-991
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    • 2022
  • Globally, several countries with sea are using eco-friendly energy resources through offshore wind power development by overcoming the weak point of the existing power generation method. The sea has the advantage of being able to develop large scale wind farms in wide waters, but the installation of marine structures threatens the safe operation of vessels. Accordingly, a standard guideline for safe navigation by analyzing the mutual effects between ship routes and offshore wind site was presented by the PIANC. Nonetheless, the standard guideline calculated the same safe distance in all situations. Therefore, this study developed a calculation model for an optimal safe distance between ship routes and offshore wind sites by reflecting the ship's maneuvering, encounter situations, environmental force, traffic density, offshore wind power generators, and channel types. As a result of the validation simulation, the developed model showed that the optimal safe distance was secured.

An Examination on the Improvement of Urbanity and Neighborship through the Provision of Collective Housing based on Small and Medium-sized Blocks (중·소블록 기반 집합주택 보급을 통한 도시성과 근린성 제고(提高) 방안의 고찰)

  • Lim, Jae Heon
    • The Journal of the Convergence on Culture Technology
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    • v.9 no.4
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    • pp.495-502
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    • 2023
  • If traditional Korean villages or residential districts have formed a community on the ground of coexisting with nature, there is a different historical development process in which many European cities have created residences for multi households on the basis of roads and blocks in fortresses. Along with the modernization of society together with large-scale housing supply, the urban landscape of series of large apartment complexes has become universal views of our urban structure; thus, the viewpoint that small and medium-sized block-based collective housing, which are more common urban structures in European cities can be linked to the improvement of urbanity and neighborship is examined. Through the process, the possibility of expanding collective housing supply based on small and medium-sized blocks as an alternative method other than complex-type apartments based on superblock, I would like to make meaningful in terms of how we can change the fundamental mutual relationship with our lifestyle and the tangible change of collective housing types which has large impact on our lives.

A Study on the Organizational Systems of Social Enterprises and The Finance in Europe and Suggestions (유럽지역의 사회적기업 조직체계 및 재원확보 방안의 비교와 한국에의 시사점)

  • Cheong, In Seo;Choi, Kap Yeol
    • International Area Studies Review
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    • v.13 no.1
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    • pp.219-240
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    • 2009
  • Through the research, we found that the organizational systems of social enterprises in Europe have both properties of limited companies and stock companies in traditional organizational structures such as cooperatives, mutual companies and associations. However, social enterprises pursue interests of entire community, allowing the interested parties to join them in comparison with cooperatives. And for finance, most of the countries mainly use public fund such as national grants, but they are using more sales revenue. However, in our country the organizational systems of social enterprises have been introduced as the government and academic circles discussed expansion of social employment within a short period. So Korean enterprises tend to depend on national support rather than profitable activities for finance. Therefore, we need to develop a Korean convention or social agreement for the organizational systems of social enterprises. Furthermore, it is important for social enterprises to secure safe finance through development of social services and social cultures such as donation.

Evaluation of RF shielding materials to improve MR image of hybrid PET/MRI

  • Hyun Keong Lim;Yong Choi;Jin Ho Jung;Jiwoong Jung;Changheun Oh;Hyun-wook Park;Jong Guk Kim
    • Journal of the Korean Physical Society
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    • v.80
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    • pp.640-646
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    • 2022
  • Hybrid PET/MRI is a useful imaging system that can improve diagnostic accuracy by providing both functional and anatomical information. However, the combination of PET and MRI can lead to mutual interference, which can degrade the performances of both imaging systems. One of the methods that is capable of preserving the performance of both modalities is to apply RF shielding to PET detectors and electronics. The purpose of this study was to propose a new RF shielding method using Au-plated conductive fabric (PCF) tape that could not only minimize RF interference and eddy current, but that could also be applied to complex PET gantry and detector module structures more easily than thin Cu foils, which have been widely used as a shielding material for hybrid PET/MRI systems. To evaluate the performance of the proposed new RF shielding method, the effects of the two RF shield materials (Cu and Au) on the B1 + field generated by the RF head coil were estimated using a computer simulation method. The effects of the Au PCF tape and Cu foil on the homogeneity and SNR of the MR image were also experimentally evaluated using a commercial 3-T MRI. The uniformity of the B1 + field map was slightly decreased by the use of Cu and Au RF shields. The deterioration in the MR image quality caused by the Au PCF tape was less than that caused by Cu foil. The simulation and experimental results indicate that Au PCF tape can serve as an alternative shielding material that reduces RF interference and eddy current for hybrid PET/MRI systems.

A Mathematics Teacher's Reflective Practice as a Process of Professional Development (전문성 신장 과정으로서의 한 수학교사의 성찰적 실천)

  • Kim, Dong-Won
    • Communications of Mathematical Education
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    • v.23 no.3
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    • pp.735-760
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    • 2009
  • Most of every teachers' life is occupied with his or her instruction, and a classroom is a laboratory for mutual development between teacher and students also. Namely, a teacher's professionalism can be enhanced by circulations of continual reflection, experiment, verification in the laboratory. Professional development is pursued primarily through teachers' reflective practices, especially instruction practices which is grounded on $Sch\ddot{o}n's$ epistemology of practices. And a thorough penetration about situations or realities and an exact understanding about students that are now being faced are foundations of reflective practices. In this study, at first, we explored the implications of earlier studies for discussing a teacher's practice. We could found two essential consequences through reviewing existing studies about classroom and instructions. One is a calling upon transition of perspectives about instruction, and the other is a suggestion of necessity of a teachers' reflective practices. Subsequently, we will talking about an instance of a middle school mathematics teacher's practices. We observed her instructions for a year. She has created her own practical knowledges through circulation of reflection and practices over the years. In her classroom, there were three mutual interaction structures included in a rich expressive environments. The first one is students' thinking and justifying in their seats. The second is a student's explaining at his or her feet. The last is a student's coming out to solve and explain problem. The main substances of her practical know ledges are creating of interaction structures and facilitating students' spontaneous changes. And the endeavor and experiment for diagnosing trouble and finding alternative when she came across an obstacles are also main elements of her practical knowledges Now, we can interpret her process of creating practical knowledge as a process of self-directed professional development when the fact that reflection and practices are the kernel of a teacher's professional development is taken into account.

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Interlayered Structures of Talc and Chlorite in the Talc Deposits of the Yugu Area, Korea (충남 유구지역 활석광상에서 관찰되는 활석과 녹니석의 혼합층상 특성)

  • Kim Geon-Young;Kim Soo Jin;Koh Yong Kwon;Bae Dae Seok
    • Journal of the Mineralogical Society of Korea
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    • v.18 no.3 s.45
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    • pp.195-204
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    • 2005
  • Interlayered structures of talc and chlorite in the talc deposits of the Yugu area are studied using transmission electron microscope. Packets of chlorite-like layer in talcs or packets of talc-like layer in chlorites are commonly observed. Randomly interlayered features of talc and chlorite are locally observed in some specimens. Reactions observed in the present study include the addition or removal of a brucite-like layer in the interlayer region of the talc or chlorite resulting in the , transformation between a talc and a chlorite layers and breakdown or formation of a talc-like layer resulting in transformation between two talc layer and one chlorite layer. Both reactions are accompanied by a significant change in volume. In addition to these mechanisms, there are two volume conserving mechanisms; the combination of both mechanisms and mutual transformation in a complex manner. Reactions from 2 chlorite layers to 3 talc layers, from 2 chlorite layers + 1 talc layers to 1 chlorite layers + 3 talc layers, and from 3 chlorite layers to 5 talc layers are observed among the complex type mechanisms.

Development of Panel-Based Rapid Aerodynamic Analysis Method Considering Propeller Effect (프로펠러 효과를 반영 가능한 패널 기반 신속 공력 해석 기법 개발)

  • Tai, Myungsik;Lee, Yebin;Oh, Sejong;Shin, Jeongwoo;Lim, Joosup;Park, Donghun
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.49 no.2
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    • pp.107-120
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    • 2021
  • Electric-powered distributed propulsion aircraft possess a complex wake flow and mutual interference with the airframe, due to the use of many propellers. Accordingly, in the early design stage, rapid aerodynamic and load analysis considering the effect of propellers for various configurations and flight conditions are required. In this study, an efficient panel-based aerodynamic analysis method that can take into account the propeller effects is developed and validated. The induced velocity field in the region of propeller wake is calculated based on Actuator Disk Theory (ADT) and is considered as the boundary condition at the vehicle's surface in the three-dimensional steady source-doublet panel method. Analyses are carried out by selecting an isolated propeller of the Korea Aerospace Research Institute (KARI)'s Quad Tilt Propeller (QTP) aircraft and the propeller-wing configuration of the former experimental study as benchmark problems. Through comparisons with the results of computational fluid dynamics (CFD) based on actuator methods, the wake velocity of propeller and the changes in the aerodynamic load distribution of the wing due to the propeller operation are validated. The method is applied to the analysis of the Optional Piloted Personal Aerial Vehicle (OPPAV) and QTP, and the practicality and validity of the method are confirmed through comparison and analysis of the computational time and results with CFD.

Analysis of the Success Factors of Open Innovation fromthe Perspective of Cooperative Game Theory: Focusing on the Case of Collaboration Between Korean Large Company 'G' and Startup 'S' (협조적 게임이론 관점에서 본 대기업-스타트업 개방형 혁신 성공 요인 분석: 대기업 'G사'와 스타트업 'S사'의 협업 사례를 중심으로)

  • Jinyoung Kim;Jaehong Park;Youngwoo Sohn
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.19 no.2
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    • pp.159-179
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    • 2024
  • Based on the case of collaboration between large companies and startups, this study suggests the importance of establishing mutual cooperation and trust relationships for the success of open innovation strategy from the perspective of cooperative game theory. It also provides implications for how this can be implemented. Due to information asymmetry and differences in organizational culture and decision-making structures between large companies and startups, collaboration is likely to proceed in the form of non-cooperative games among players in general open innovation, leading to the paradox of open innovation, which lowers the degree of innovation. Accordingly, this study conducted a case study on collaboration between large company 'G' and startup 'S' based on the research question "How did we successfully promote open innovation through cooperative game-type collaboration?" The study found that successful open innovation requires (1) setting clear collaboration goals to solve the organizational problem between large companies and startups, (2) supporting human resources for qualitative growth of startups to solve reliability problems, (3) leading to strategic investment and joint promotion of new projects to solve the profit distribution problem. This study is significant in that it contributes to expanding the discussion of the success factors of open innovation to the importance of interaction and strategic judgment considering the organizational culture and decision-making structure among players, and empirically confirming the success conditions of open innovation from the perspective of cooperative game theory.

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Genetic Relationship and Structural Characteristics of the Fe-Ti Ore Body and the Sancheong Anorthosite, Korea (산청 회장암과 철-티탄 광체의 구조적 특징과 발생적 관계)

  • Kang, Ji-Hoon;Lee, Deok-Seon
    • Economic and Environmental Geology
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    • v.47 no.6
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    • pp.571-588
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    • 2014
  • It consists of the Precambrian Jirisan metamorphic complex and Sancheong anorthosite complex and the Mesozoic granitoids which intrude them in the Sancheong area, the Jirisan province of Yeongnam massif, Korea. The study area is located in the western part of the stock-type Sancheong anorthosite complex. We performed a detailed fieldwork on the Sancheong anorthosite (SA) and Fe-Ti ore body (FTO) which constitute the Sancheong anorthosite complex, and reinterpreted the origin of FTO foliation and the genetic relationship between them from the foliations, shear zones, occurrences of the SA and FTO. The new structural characteristics between them are as follows: the multilayer structures of FTO, the derived veins of straight, anastomosing uneven types and block structures related to the size reduction of SA, the gradual or irregular boundaries of SA blocks and FTO showing bulbous lobate margins and comb structures, the FTO foliation and linear arrangements of flow occurrence which is not ductile shear deformation, the discontinuous shear zone of SA, the orientation of FTO foliations parallel to the boundaries of SA blocks, the predominance of FTO foliations toward the boundaries of SA blocks and being proportional to the aspect ratio of plagioclase xenocrysts and SA xenoblocks, and the flow folding structures of FTO foliation. Such field evidences indicate that the SA is not fully congealed when the FTO is melt and the fracturing of partly congealed SA causes the derived veins of FTO and the size reduction of SA. Also the gradual or irregular boundaries of SA blocks and FTO result from the mutual reaction between the not fully congealed SA blocks and the FTO melt, and the FTO foliation is a magmatic foliation which was formed by the interaction between the FTO melt and the partly congealed SA blocks. Therefore, these suggest that the SA and FTO are not formed from the intrusion of different magmas in genesis and age but from a coeval and cogenetic magma through multiple fractionation. We predict that the FTO will show an very irregular occurrence injected along irregular fractures, not the regular occurrence like as the intrusive vein and dike. It can be applied to the designing of Fe-Ti mineral resource exploration in this area.

Virtuous Concordance of Yin and Yang and Tai-Ji in Joseon art: Focusing on Daesoon Thought (조선 미술에 내재한 음양합덕과 태극 - 대순사상을 중심으로 -)

  • Hwang, Eui-pil
    • Journal of the Daesoon Academy of Sciences
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    • v.35
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    • pp.217-253
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    • 2020
  • This study analyzes the principles of the 'Earthly Paradise' (仙境, the realm of immortals), 'Virtuous Concordance of Yin and Yang' (陰陽合德), and the 'Reordering Works of Heaven and Earth' (天地公事) while combining them with Joseon art. Therefore, this study aims to discover the context wherein the concept of Taiji in 'Daesoon Truth,' deeply penetrates into Joseon art. Doing so reveals how 'Daesoon Thought' is embedded in the lives and customs of the Korean people. In addition, this study follows a review of the sentiments and intellectual traditions of the Korean people based on 'Daesoon Thought' and creative works. Moreover, 'Daesoon Thought' brings all of this to the forefront in academics and art at the cosmological level. The purpose of this research is to vividly reveal the core of 'Daesoon Thought' as a visual image. Through this, the combination of 'Daesoon Thought' and Joseon art will secure both data and reality at the same time. As part of this, this study deals with the world of 'Daesoon Thought' as a cosmological Taiji principle. This concept is revealed in Joseon art, which is analyzed and examined from the viewpoint of art philosophy. First, as a way to make use of 'Daesoon Thought,' 'Daesoon Truth' was developed and directly applied to Joseon art. In this way, reflections on Korean life within 'Daesoon Thought' can be revealed. In this regard, the selection of Joseon art used in this study highlights creative works that have been deeply ingrained into people's lives. For example, as 'Daesoon Thought' appears to focus on the genre painting, folk painting, and landscape painting of the Joseon Dynasty, attention is given to verifying these cases. This study analyzes 'Daesoon Thought,' which borrows from Joseon art, from the perspective of art philosophy. Accordingly, attempts are made to find examples of the 'Virtuous Concordance of Yin and Yang' and Tai-Ji in Joseon art which became a basis by which 'Daesoon Thought' was communicated to people. In addition, appreciating 'Daesoon Thought' in Joseon art is an opportunity to vividly examine not only the Joseon art style but also the life, consciousness, and mental world of the Korean people. As part of this, Chapter 2 made several findings related to the formation of 'Daesoon Thought.' In Chapter 3, the structures of the ideas of 'Earthly Paradise' and 'Virtuous Concordance of Yin and Yang' were likewise found to have support. And 'The Reordering Works of Heaven and Earth' and Tai-Ji were found in depictions of metaphysical laws. To this end, the laws of 'The Reordering Works of Heaven and Earth' and the structure of Tai-Ji were combined. In chapter 4, we analyzed the 'Daesoon Thought' in the life and work of the Korean people at the level of the convergence of 'Daeesoon Thought' and Joseon art. The analysis of works provides a glimpse into the precise identity of 'Daesoon Thought' as observable in Joseon art, as doing so is useful for generating empirical data. For example, works such as Tai-Jido, Ssanggeum Daemu, Jusachaebujeokdo, Hwajogi Myeonghwabundo, and Gyeongdodo are objects that inspired descriptions of 'Earthly Paradise', 'Virtuous Concordance of Yin and Yang,' and 'The Reordering Works of Heaven and Earth.' As a result, Tai-Ji which appears in 'Daesoon Thought', proved the status of people in Joseon art. Given all of these statements, the Tai-Ji idea pursued by Daesoon Thought is a providence that follows change as all things are mutually created. In other words, it was derived that Tai-Ji ideology sits profoundly in the lives of the Korean people and responds mutually to the providence that converges with 'Mutual Beneficence.'