• Title/Summary/Keyword: Closed-Structure

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Building Index of Sustainability and Limits to Creating Shared Value in Vietnamese Coffee Industry (베트남 커피산업의 지속가능성 지표 구축과 공유가치창출의 한계)

  • Ji, Hochul;Lee, Sung-Cheol
    • Journal of the Economic Geographical Society of Korea
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    • v.21 no.4
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    • pp.289-302
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    • 2018
  • As business activities of firms for maximizing profits has resulted in increases in economic, social and environmental problems in regional geographies, they have stimulated some social activities through enhancing their public image and justifying their conducts. In fact, firms have been given concerned with a decrease in profits due to the promotion of their social activities required by local communities. However, firms are able to create shared value resulted in added value creation centering on shareholder as well as stakeholder by expanding increases in economic and social values. Therefore, the main purpose of this research is to draw an index which is able to evaluate the mechanism of virtuous circle resulted from creating shared value(hereafter CSV). At the same time, it has attempted to analyze some limits to and real effects of CSV by the index. The paper has analyzed the CSV of certificated coffee by using the index of sustainability in the Vietnamese coffee industry. The introduction of certificated coffee showed positive effects in the order of environmental, economic and social indicators. However, the structure of closed decision-making in Vinacafe, which is a state-firm, has not able to secure enough economic profits for CSV, leading to some limits to the formation of virtuous circles in the Vietnamese certificated coffee industry.

Seismic Performance Assessment of a Composite Modular System Considering Stiffness of Connections (접합부 강성을 고려한 합성 모듈러 시스템의 내진 성능평가)

  • Choi, Young-Hoo;Lee, Ho-Chan;Kim, Jin-Koo
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.23 no.1
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    • pp.9-18
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    • 2019
  • Modular system can be divided into two types based on the methods of resisting load. The one is the open-sided modular system composed of beams and columns. The other is the enclosed modular system composed of panels and studs. Of the Modular systems, the use of open-sided modular system is limited because it consists of closed member sections. In order to solve this problem, Choi et al.(2017) proposed a composite modular system with folded steel members filled with concrete. However, it was assumed in the previous study that the connections between modules are composed of rigid joint. Therefore it didn't identify the effect of connection behavior in structure. This study used finite element analysis to calculate stiffness of the connections in the proposed modular system. The linearization method presented in FEMA 440 is used for seismic performance assessment of structures, considering the connection stiffness computed in this study. The result of analysis shows that the capacity and story drift ratio obtained in the model considering stiffness of connection are less than those in the model not considering connection stiffness. Based on this observation, it is concluded that the stiffness of connection has a considerable effect on structural behavior.

A Study on the 3D Reconstruction and Historical Evidence of Recumbent Buddha Based on Fusion of UAS, CRP and Terrestrial LiDAR (UAS, CRP 및 지상 LiDAR 융합기반 와형석조여래불의 3차원 재현과 고증 연구)

  • Oh, Seong-Jong;Lee, Yong-Chang
    • Journal of Cadastre & Land InformatiX
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    • v.51 no.1
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    • pp.111-124
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    • 2021
  • Recently, Interest in the restoration and 3D reconstruction of cultural properties due to the fire of Notre Dame Cathedral on April 15, 2019 has been focused once again after the 2008 Sungnyemun fire incident in South Korea. In particular, research to restore and reconstruct the actual measurement of cultural properties using LiDAR(Light Detection and ranging) and conventional surveying, which were previously used, using various 3D reconstruction technologies, is being actively conducted. This study acquires data using unmanned aerial imagery of UAV(Unmanned Aerial Vehicle), which has recently established itself as a core technology in the era of the 4th industrial revolution, and the existing CRP(Closed Range Photogrammetry) and terrestrial LiDAR scanning for the Recumbent Buddha of Unju Temple. Then, the 3D reconstruction was performed with three fusion models based on SfM(Structure-from-Motion), and the reproducibility and accuracy of the models were compared and analyzed. In addition, using the best fusion model among the three models, the relationship with the Polar Star(Polaris) was confirmed based on the real world coordinates of the Recumbent Buddha, which contains the astronomical history of Buddhism in the early 11th century Goryeo Dynasty. Through this study, not only the simple external 3D reconstruction of cultural properties, but also the method of reconstructing the historical evidence according to the type and shape of the cultural properties was sought by confirming the historical evidence of the cultural properties in terms of spatial information.

A Study on the Application of a Drone-Based 3D Model for Wind Environment Prediction

  • Jang, Yeong Jae;Jo, Hyeon Jeong;Oh, Jae Hong;Lee, Chang No
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.39 no.2
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    • pp.93-101
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    • 2021
  • Recently, with the urban redevelopment and the spread of the planned cities, there is increasing interest in the wind environment, which is related not only to design of buildings and landscaping but also to the comfortability of pedestrians. Numerical analysis for wind environment prediction is underway in many fields, such as dense areas of high-rise building or composition of the apartment complexes, a precisive 3D building model is essentially required in this process. Many studies conducted for wind environment analysis have typically used the method of creating a 3D model by utilizing the building layer included in the GIS (Geographic Information System) data. These data can easily and quickly observe the flow of atmosphere in a wide urban environment, but cannot be suitable for observing precisive flow of atmosphere, and in particular, the effect of a complicated structure of a single building on the flow of atmosphere cannot be calculated. Recently, drone photogrammetry has shown the advantage of being able to automatically perform building modeling based on a large number of images. In this study, we applied photogrammetry technology using a drone to evaluate the flow of atmosphere around two buildings located close to each other. Two 3D models were made into an automatic modeling technique and manual modeling technique. Auto-modeling technique is using an automatically generates a point cloud through photogrammetry and generating models through interpolation, and manual-modeling technique is a manually operated technique that individually generates 3D models based on point clouds. And then the flow of atmosphere for the two models was compared and analyzed. As a result, the wind environment of the two models showed a clear difference, and the model created by auto-modeling showed faster flow of atmosphere than the model created by manual modeling. Also in the case of the 3D mesh generated by auto-modeling showed the limitation of not proceeding an accurate analysis because the precise 3D shape was not reproduced in the closed area such as the porch of the building or the bridge between buildings.

Development of jigs for planar measurement with DIC and determination of magnesium material properties using jigs (마그네슘 합금 판재의 평면 DIC 측정을 위한 지그 개발과 이를 활용한 단축 변형 특성 분석)

  • Kang, Jeong-Eun;Yoo, Ji-Yoon;Choi, In-Kyu;YU, Jae Hyeong;Lee, Chang-Whan
    • Design & Manufacturing
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    • v.15 no.2
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    • pp.23-29
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    • 2021
  • The specific strength of magnesium alloy is four times that of iron and 1.5 times that of aluminum. For this reason, its use is increasing in the transportation industry which is promoting weight reduction. At room temperature, magnesium alloy has low formability due to Hexagonal closed packed (HCP) structure with relatively little slip plane. However, as the molding temperature increases, the formability of the magnesium alloy is greatly improved due to the activation of other additional slip systems, and the flow stress and elongation vary greatly depending on the temperature. In addition, magnesium alloys exhibit asymmetrical behavior, which is different from tensile and compression behavior. In this study, a jig was developed that can measure the plane deformation behavior on the surface of a material in tensile and compression tests of magnesium alloys in warm temperature. A jig was designed to prevent buckling occurring in the compression test by applying a certain pressure to apply it to the tensile and compression tests. And the tensile and compressive behavior of magnesium at each temperature was investigated with the developed jig and DIC equipment. In each experiment, the strain rate condition was set to a quasi-static strain rate of 0.01/s. The transformation temperature is room temperature, 100℃. 150℃, 200℃, 250℃. As a result of the experiment, the flow stress tended to decrease as the temperature increased. The maximum stress decreased by 60% at 250 degrees compared to room temperature. Particularly, work softening occurred above 150 degrees, which is the recrystallization temperature of the magnesium alloy. The elongation also tended to increase as the deformation temperature increased and increased by 60% at 250 degrees compared to room temperature. In the compression experiment, it was confirmed that the maximum stress decreased as the temperature increased.

The Social Dilemma of Chinese Village Community: Focusing on the Film (중국 마을 공동체의 사회적 딜레마: 영화 <빈관>을 중심으로)

  • Sun, Ming-Yue;Lee, Hee-Seung
    • Journal of Digital Convergence
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    • v.19 no.5
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    • pp.375-381
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    • 2021
  • This study aimed to examine the dilemma of rural China under rapid urbanization process after economic reform, by paying attention to the problem of the order of village community and the expression of individual desires depicted in the film with a rural background. To this end, the narrative analysis, which is suitable for exploring the story structure and expression style of the text, was conducted to examine the community order and ethics, patriarchy and paternity, and the expression of desires of subject. In the film, closed space and villagers, who are disciplined by community customs, local culture, and formality of the rule of manners, are depicted. The film is covered in a form of mystery movie dealing with the deaths of members of the village community. However, the film talks about the rise of the Imaginary desire of subject against the symbolic rules of community order and ethics through the puzzle pieces story according to the perspectives of the characters. In conclusion, through the narrative analysis, it was possible to examine the implications of weakened communal discipline and paternity of the countryside by the rapid urbanization of China, and implications of the lethargy and neurosis of the subjects.

A Basic Study on the Generation of Tire & Road Wear Particles by Differences in Tire Wear Performance (타이어 마모성능 차이에 의한 타이어 마모입자 생성에 관한 기초 연구)

  • Kang, Tae-Woo;Kim, Hyeok-Jung
    • Journal of the Korean Recycled Construction Resources Institute
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    • v.9 no.4
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    • pp.561-568
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    • 2021
  • In this study, in order to observe the change in the amount of Tire and Road Wear Particles and the ratio of tire components in it according to the tire wear resistance performance, carried out the evaluation by varying the vulcanization reaction design of the tire tread rubber. In addition, in order to improve the reliability of the evaluation of Tire and Road Wear Particles, the evaluation was performed indoor laboratory test equipment that simulates the condition on real driving to exclude various environmental influences including minerals, driver's habits, road surface, weather, tire structure and pattern designs. After the evaluation in closed space, it is estimated that the amount of collected Tire and Road Wear Particles is 84% compared to 100% of the tire and road wear loss weight, of which 96.4~97.7% was around the road and 2.3~3.6% was in the air. As a result of analy sis of the collected Tire and Road Wear particles, the tire component existed 63~75% in the Tire and Road Wear Particles depending on the wear resistance performance of the tire.

Study on selection and basic specifications design of shield TBM for power cable tunnels (터널식 전력구 쉴드TBM 선정 및 기본설계 사양 제시에 관한 연구)

  • Jung Joo Kim;Ji Yun Lee;Hee Hwan Ryu;Ju Hwan Jung;Suk Jae Lee;Du San Bae
    • 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.

Reliability Estimation of Static Design Methods for Driven Steel Pipe Piles in Korea (국내 항타강관말뚝 설계법의 신뢰성평가)

  • Huh, Jung-Won;Park, Jae-Hyun;Kim, Kyung-Jun;Lee, Ju-Hyung;Kwak, Ki-Seok
    • Journal of the Korean Geotechnical Society
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    • v.23 no.12
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    • pp.61-73
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    • 2007
  • As a part of Load and Resistance Factor Design(LRFD) code development in Korea, in this paper an intensive reliability analysis was performed to evaluate reliability levels of the two static bearing capacity methods for driven steel pipe piles adopted in Korean Standards for Structure Foundations by the representative reliability methods of First Order Reliability Method(FORM) and Monte Carlo Simulation(MCS). The resistance bias factors for the two static design methods were evaluated by comparing the representative measured bearing capacities with the design values. In determination of the representative bearing capacities of driven steel pipe piles, the 58 data sets of static load tests and soil property tests were collected and analyzed. The static bearing capacity formula and the Meyerhof method using N values were applied to the calculation of the expected design bearing capacity of the piles. The two representative reliability methods(FORM, MCS) based computer programs were developed to facilitate the reliability analysis in this study. Mean Value First Order Second Moment(MVFOSM) approach that provides a simple closed-form solution and two advanced methods of FORM and MCS were used to conduct the intensive reliability analysis using the resistance bias factor statistics obtained, and the results were then compared. In addition, a parametric study was conducted to identify the sensibility and the influence of the random variables on the reliability analysis under consideration.

International Comparison of Decoupling of Greenhouse Gas Emissions in the Steel Industry (철강산업의 온실가스 배출 탈동조화 국제비교)

  • Kim, Dong Koo
    • Environmental and Resource Economics Review
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    • v.31 no.1
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    • pp.113-139
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    • 2022
  • The iron and steel industry is a manufacturing industry with the largest greenhouse gases emissions and has a great ripple effect on the national economy as a core material industry. This study internationally compared the decoupling patterns of greenhouse gases emissions in the iron and steel industry from 1990 to 2019, focusing on Korea, Japan, and Germany. In particular, unlike previous studies that considered only fuel combustion emissions, this study considered all fuel combustion emissions, industrial process emissions, and indirect emissions from the use of electricity and heat. As a result of the analysis, Korea is interpreted as expansive coupling, Japan as decoupling, and Germany as unclear. Therefore, the decoupling path that the Korean iron and steel industry should take should not be in Germany, but in the form of seeking a decoupling method similar to Japan or more effective than Japan. In addition, this study considered the characteristics of the iron and steel industry as much as possible and presented the causes of the decoupling analysis results and implications for the Korean iron and steel industry through comparison with Japan and Germany. In particular, four factors were suggested as factors which has promoted decoupling in Japan: high value-added of Japanese iron and steel products, development of energy efficiency technology in the Japanese iron and steel industry, strategic M&A of the Japanese iron and steel industry, and maintaining competitiveness according to the closed distribution structure of Japanese iron and steel products. The Korean iron and steel industry should also use the case of Japan as a benchmark to further increase added value through quality uprade and product diversification of iron and steel products, while at the same time making efforts to fundamentally reduce greenhouse gas emissions through the development of new technologies.