• Journal of the Earthquake Engineering Society of Korea
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• v.8 no.2
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• pp.73-81
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• 2004

In this study, experimental research was carried out to improve earthquake-resistant performance for the retrofitting of reinforced concrete beam-column joints using carbon fiber materials in existing reinforced concrete building. Six reinforced concrete beam-column joints were constructed and tested to evaluate the retrofitting effect of test variables, such as the retrofitting materials and retrofitting region(plastic hinge, beam-column joint) under load reversals. Test results show that retrofitting specimen(RPC-CP2, RPC-CR, RJC-CP, RJC-CR), using new materials(carbon fiber plate, carbon fiber rod and carbon fiber sheet), designed by the improvement of earthquake-resistant performance and ductility, attained more load-carrying capacity and stable hysteretic behavior.

• Advances in aircraft and spacecraft science
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• v.9 no.6
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• pp.525-536
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• 2022

The current state of telecommunications infrastructure in the Arctic does not allow providing a wide range of required services for people, businesses and other categories, which necessitates the use of non-traditional approaches to its organization. The paper proposes an innovative approach to building a combined communication network based on tethered high-altitude platform station (HAPS) located at an altitude of 1-7 km and connected via radio channels with terrestrial and satellite communication networks. Network configuration and composition of telecommunication equipment placed on HAPS and located on the terrestrial and satellite segment of the network was justified. The availability of modern equipment and the distributed structure of such an integrated network will allow, unlike existing networks (Iridium, Gonets, etc.), to organize personal mobile communications, data transmission and broadband Internet up to 100 Mbps access for mobile and fixed subscribers, rapid transmission of information from Internet of Things (IoT) sensors and unmanned aerial vehicles (UAV). A substantiation of the possibility of achieving high network capacity in various paths is presented: inter-platform radio links, subscriber radio links, HAPS feeder lines - terrestrial network gateway, HAPS radio links - satellite retransmitter (SR), etc. The economic efficiency of the proposed solution is assessed.

• Earthquakes and Structures
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• v.8 no.2
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• pp.305-377
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• 2015

The problem of earthquake induced torsion in buildings is quite old and although it has received a lot of attention in the past several decades, it is still open. This is evident not only from the variability of the pertinent provisions in various modern codes but also from conflicting results debated in the literature. Most of the conducted research on this problem has been based on very simplified, highly idealized models of eccentric one-story systems, with single or double eccentricity and with load bearing elements of the shear beam type, sized only for earthquake action. Initially, elastic models were used but were gradually replaced by inelastic models, since building response under design level earthquakes is expected to be inelastic. Code provisions till today have been based mostly on results from one-story inelastic models or on results from elastic multistory idealizations. In the past decade, however, more accurate multi story inelastic building response has been studied using the well-known and far more accurate plastic hinge model for flexural members. On the basis of such research some interesting conclusions have been drawn, revising older views about the inelastic response of buildings based on one-story simplified model results. The present paper traces these developments and presents new findings that can explain long lasting controversies in this area and at the same time may raise questions about the adequacy of code provisions based on results from questionable models. To organize this review better it was necessary to group the various publications into a number of subtopics and within each subtopic to separate them into smaller groups according to the basic assumptions and/or limitations used. Capacity assessment of irregular buildings and new technologies to control torsional motion have also been included.

• Structural Engineering and Mechanics
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• v.30 no.6
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• pp.733-761
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• 2008

The failure of reinforced concrete structures in recent earthquakes caused concern about the performance of beam column joints. Confinement of joint is one of the ways to improve the performance of beam column joints during earthquakes. This paper describes an experimental study of exterior beam-column joints with two non-conventional reinforcement arrangements. One exterior beam-column joint of a six story building in seismic zone III of India was designed for earthquake loading. The transverse reinforcement of the joint assemblages were detailed as per IS 13920:1993 and IS 456:2000 respectively. The proposed nonconventional reinforcement was provided in the form of diagonal reinforcement on the faces of the joint, as a replacement of stirrups in the joint region for joints detailed as per IS 13920 and as additional reinforcement for joints detailed as per IS 456. These newly proposed detailing have the basic advantage of reducing the reinforcement congestion at the joint region. In order to study and compare the performance of joint with different detailing, four types of one-third scale specimens were cast (two numbers in each type). The main objective of the present study is to investigate the effectiveness of the proposed reinforcement detailing. All the specimens were tested under reverse cyclic loading, with appropriate axial load. From the test results, it was found that the beam-column joint having confining reinforcement as per IS: 456 with nonconventional detailing performed well. Test results indicate that the non-conventionally detailed specimens, Type 2 and Type 4 have an improvement in average ductility of 16% and 119% than their conventionally detailed counter parts (Type1 and Type 3). Further, the joint shear capacity of the Type 2 and Type 4 specimens are improved by 8.4% and 15.6% than the corresponding specimens of Type 1 and Type 3 respectively. The present study proposes a closed form expression to compute the yield and ultimate load of the system. This is accomplished using the theory of statics and the failure pattern observed during testing. Good correlation is found between the theoretical and experimental results.

• Journal of the Korea Concrete Institute
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• v.15 no.1
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• pp.11-16
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• 2003

The objective of this study is to clarify the seismic capacity and the characteristics in the hysteretic behavior of RC structures with non-seismic detailing. To do this, an exterior beam-column subassemblage was selected from a ten story RC building and six 1/3-scale specimens were manufactured with three variables; (1) with and without slab, (2) upward and downward direction of anchorage for the bottom bar in beams, and (3) with and without hoop bars in the joint region. The test results have shown that (1) the existence of slab increased the strength in positive and negative moment, 25% and 52%, respectively; (2) the Korean practice of anchorage (downward and 25 $d_{b}$ anchorage length) caused the 8% reduction of strength and the early strength degradation in comparison with the case of seismic details; and (3) the existence of hoop bars in the joint region shows significant role in preventing the pull-out.t.

• Proceedings of the Korea Water Resources Association Conference
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• 2011.05a
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• pp.21-21
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• 2011

Many Asian countries are suffered from various problems on water, which include the need for increased access to improves water supplies and sanitation through investments in infrastructure and capacity building, the balances water management system between development and ecosystem, and the need to reduce the human populations'vulnerability to water-related disasters, in particular, from climate variability and evolution. Decison makers are the most influential people in policy making and solving global water problems is central issue in eradicating poverty and achieving sustainable development (MDG). They across the world form an integral part of the architecture of national or regional governance. Their role covers a range of decision-making processes including passing legislation, scrutinizing government policy, and representing citizen through the election. We must ensure that these quiet but important issues get the political space, financial priority and public attention they deserve. Regional bodies such as the EU have also enacted legislation which introduces rules on water quality and other enforceable mattera across state boundaries. With this growing body of laws and policies on water issues, the role of decision makers is growing. Recognizing this role, decison makers' platform is essential to provide an opportunity to discuss crucial water issues in each country or region and for the purpose "2010 Parliaments for Water in Asia" has planned and organized to investigate our common issues and goals. During the meeting, we have an opportunity to observe water policy of Bangladesh, Bhutan, China, Mongolia, New Zealand and the Philippines and share the views on what needs to be done to move forward by decision makers for the future of water. In conclusion, the process of developing the decision makers' platform in each region would be ultimately essential point to increase the awareness of the developed and developing countries' roles, knowledge to clarify roles and responsibilities of each stake holders and finally be a major actor for resolving not only water challenges also issues of human settlements.

• The Journal of the Korea Contents Association
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• v.21 no.8
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• pp.424-441
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• 2021

The research is to analyze current situation of the coordinated development of "5 Region" and "4 Road" in Henan Province and put forward problems about the coordinated development of the "5 Region" and "4 Road" with the inland geographical location in China by drawing on the experience of the coordinated development of related industries in developed countries and regions based on China's "One Belt And One Road". According to the problems, a plan for the promotion of opening up to the outside world is provided. Through research, the following problems are found: First, the superposition advantage of five districts' and "four roads' has not been fully brought into play. Second, the collaborative linkage mechanism is not sound. Third, modern comprehensive transportation hub facilities are not fully completed. Fourth, the industrial support capacity is insufficient. Fifth, basic support is difficult to meet the needs of future development. The plan is as follows: First, building a top-level strategic platform and improve the policy support system. Second, we need to enhance the advantages of the four Silk Roads and accelerate their interconnected development. Third, establishing a coordination and mutual assistance mechanism to stimulate the superposition effect of industrial clusters. The significance of this study is that it can be used as research data to predict the future direction of China's "One Belt and One Road" policy and enlightenment to stimulate the economic revitalization of inland provinces.

• Journal of Korea Water Resources Association
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• v.51 no.spc
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• pp.1105-1115
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• 2018

In Korea, there are only a few cases that quantitative evaluate the impacts of climate change on water supply. Therefore, to ensure stable water supply in the future, a water resources plan is needed to establish by analyzing the scenarios that take into consideration the various situations in the future. In this study, we analyzed the changes of various situations for the Nakdong River basin, and constructed it for the future scenario. The stability of the water supply was analyzed through the analysis of water supply and demand prospect for each scenario path. We selected the areas expected to experience difficulty in supplying water supply and analyzed the scenarios of future water shortage by region and water sector. Also, the effect of increasing water supply capacity through optimal integrated operation of water supply facilities was analyzed and presented. Analysis of the results shows that there is a difficulty in supplying water due to future climate change experienced in the Nakdong River basin. Therefore it is necessary to prepare various countermeasures in order to mitigate or solve this problem.

• Journal of Korean Library and Information Science Society
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• v.53 no.2
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• pp.215-239
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• 2022

All public libraries are local public goods and cultural infrastructures whose ideological pillars are publicly operated, free, and open to all. This identity is justified when the public library provides various knowledge information, various programs, and community space to local residents within the service area, and ultimately contributes to the cultural development of the nation and society. To this end, the country and local governments must expand the number of individuals that meet legal standards, deploy competent professionals, and provide facilities and spaces that are easy to access and use. However, if there is a gap in infrastructure and services between regional public libraries, it causes inequality in access and use of residents, which inevitably leads to information gap and cultural welfare gap. Therefore, this study was analyzed the relative gap using the location quotient, key infrastructure indicators and service indicators of public libraries of regional government in Korea and basic local government in the Chungnam region from the viewpoint that the balanced development and capacity building of public libraries must precede the establishment of a public library in Chungnam region as a life-friendly knowledge information service institution, culture enjoyment and lifelong learning space. Based on the results, a method to resolve the gap was suggested by dividing the elements of gaps in public libraries into accessibility, core infrastructure, and services, focusing on vulnerable cities and counties in the Chungnam region.

• Journal of the Korean Society for Library and Information Science
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• v.44 no.1
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• pp.267-295
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• 2010

The Library Act, which was revised in 2006, stipulates that systematical organizations should be established concentrating on the responsibilities and roles of the central government and local metropolitan municipalities in connection with the application of library policies. According to the Act, the Regional Central Library is supposed to apply the library policies covering all kinds of local libraries. Through trial cooperative operation led by the Regional Central Library and survey and discussion among staff, this study reviewed the possible alternatives for coordination in a region focusing on the Regional Central Library. The study proposed a 'Cooperative systematic model led by the Regional Central Library', an 'Operational model', and a 'Step-by-step execution plan' in consideration of the types of regions, the class of the libraries, and their fields. In addition, it presented a 'Scheme for the appointment, establishment, and coordination of the Regional Central Library', a 'Scheme for systematic enhancement', and a 'Scheme for the capacity building of respective libraries'.