• Journal of the Korea Organic Resources Recycling Association
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• v.31 no.1
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• pp.47-56
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• 2023

This study describes the successful synthesize strategy for the silica nanoparticles utilizing various water sources, including tap, industrial, and stream waters without using deionized water. Also, as-synthesized silica nanoparticles are employed as dispersive materials for the electro-responsive smart fluid application. Specifically, homogeneous silica nanoparticles with sizes of 500-700nm are successfully prepared in large scale at once (ca. 12.0 g) with the described experimental method and showing similar structural and chemical characteristics with silica nanoparticles synthesized using the deionized water. The size of silica nanoparticles are varied according to the ion conductivity differences of tap, industrial, stream water, and deionized water. The size of silica nanoparticles decresed with the increased ion conductivity, indicating the ion suppression of growth of silica nanoparticles. Moreover, as-synthesized silica nanoparticles from various water sources of electro-responsive characteristic are investigated by the smart fluid application. The smart fluids containing silica nanoparticles synthesized by tap, industrial, and stream water exhibited higher shear stress compared to the deionized water, owing to the more rigid fibril-like structures formed by the smaller silica nanoparticles. Conclusively, uniform silica nanoparticles from various water sources without any purification are able to successfully prepared without usage of deionized water and resulting silica nanoparticles manifested higher electro-responsive performance.

• Journal of Korea Water Resources Association
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• v.56 no.6
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• pp.403-417
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• 2023

In this research, a methodology was developed for constructing an appropriate rainfall image database for estimating rainfall intensity based on CCTV video. The database was constructed in the Large-Scale Climate Environment Chamber of the Korea Conformity Laboratories, which can control variables with high irregularity and variability in real environments. 1,728 scenarios were designed under five different experimental conditions. 36 scenarios and a total of 97,200 frames were selected. Rain streaks were extracted using the k-nearest neighbor algorithm by calculating the difference between each image and the background. To prevent overfitting, data with pixel values greater than set threshold, compared to the average pixel value for each image, were selected. The area with maximum pixel variability was determined by shifting with every 10 pixels and set as a representative area (180×180) for the original image. After re-transforming to 120×120 size as an input data for convolutional neural networks model, image augmentation was progressed under unified shooting conditions. 92% of the data showed within the 10% absolute range of PBIAS. It is clear that the final results in this study have the potential to enhance the accuracy and efficacy of existing real-world CCTV systems with transfer learning.

• Korean Journal of Ecology and Environment
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• v.55 no.1
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• pp.1-9
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• 2022

An estuary is an area where a freshwater river or stream meets the ocean. Even before the importance of the value of estuaries was recognized, the estuary was lost because of large-scale conversion by draining, filling, damming, and dredging. In South Korea, 643 estuaries are located, and the total area is 3,248,300 ha, accounting for 32.5% of the total area of South Korea. Over 35% of Korean estuaries are closed estuaries which are only temporally connected with the sea, either permanently or periodically. Since 2008, in order to preserve the estuary ecosystem and solve major issues in the estuary by accumulating knowledge about the estuarine ecosystem, the Ministry of Environment of Republic of Korea has been conducting the "Estuarine Ecosystem Monitoring and Assessment Project". At 668 sites of 325 estuaries, epilithic diatom, benthic macroinvertebrate, fish, and vegetation are investigated, and the habitat condition of each site is evaluated using the newly developed biotic index. More than 100 researchers annually record 2,097 species of estuaries according to the standardized survey guidelines over the past 14 years and provide strictly managed data necessary for establishing estuaries conservation policies. As a result of bibliometric analysis of 1,195 research articles related to the monitoring and assessment of the estuarine ecosystem, research on pollutants such as heavy metals and sediment control have recently been conducted. "Estuarine Ecosystem Monitoring and Assessment Project" is an ecological monitoring type of long-term mandated monitoring that is usually focused on identifying trends. Although it is difficult to identify the mechanism influencing a change in an ecosystem through long-term mandated monitoring, providing empirical data for supporting evidence-based policy, decision-making, and the management of ecosystems. In order to increase the efficiency of the project, research to investigate the relationship between sediments and pollutants and organisms can be conducted at specific estuaries or sites to compensate for the shortcomings of mandatory monitoring.

• Korean Journal of Heritage: History & Science
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• v.56 no.1
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• pp.182-205
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• 2023

The use of royal artificial flowers was finally found through schematics and records in Wonhaeng Eulmyojeongri Uigwe, which organized the procession to Hwaseong in 1795. The results of classifying the uses of artificial flowers in the brthday banquet at Bongsudang Hall in 1795 and considering the shape, user, and usage are as follows. According to literature records, artificial flowers were made with high-quality materials such as gold, silver, and silk thread in the early period, but were mainly made of paper in the later period. Artificial flowers were used for decorating official hats, Bongsudang Hall, and banquet tables. The Sagwonhwa was used for decoration of the official hats of members of the royal family, and the one on the top was called Eosam-Sagwonhwa. At the birthday banquet inBongsudang Hall, King Jeongjo and Hyegyeonggung used the Eosam-Sagwonhwa and put it on the right side of the official hats. Officials put peach blossom with two petals on the left side of the official hats for decoration. The artificial flowers for decoration of the official hats of musicians and dancers were more expensive and flashier than the officials' ones. Depending on the dance, several artificial flowers were inserted into the official hats. When measuring the size of artificial flowers, the scale used was when making a ceremonial article. For artificial flowers for decoration of the banquet hall, red and white peach blossoms were placed in two jars with dragons painted on them and them placed on two red-painted tables, respectively. The table and jar with flowers were tied together with a red cotton string and fixed so as not to fall over. The artificial flowers for decoration of the banquet table of King Jeongjo, Hyegyeonggung, and the king's sisters were a large lotus, medium-sized lotus, peony, rose, and specially made peach flowers. The artificial flowers for decoration of the banquet table of guests and officials were small lotuses and peach blossoms. The artificial flowers used in the birthday banquet at Bongsudang Hall the most were peach blossoms, and peaches had the meaning of longevity and exorcism. It is expected that the above research results will be helpful in understanding the characteristics and usage of artificial flowers in the period of King Jeongjo and use in reproducing royal feasts and producing traditional cultural contents.

• Journal of the Korean Institute of Landscape Architecture
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• v.51 no.3
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• pp.21-36
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• 2023

As a solution to environmental issues, such as climate change response, the carbon neutrality strategy, urban heat islands, fine dust, and biodiversity enhancement, the value of urban green spaces and trees are becoming important, and various studies dealing with the effects of trees for environmental improvement are being conducted. This study comprehensively considers the preceding studies on planting tree species, planting structure, planting density, and planting base to propose a direction for the planting renewal of green areas in urban parks and applies the findings to a renewal plan to improve the urban environment through landscaping trees. A field survey was conducted on the planting status of Seoul Children's Grand Park, a large-scale neighborhood park in Seoul, and based on the survey data, a planting function evaluation was conducted, and areas needing improvement in planting function were identified. The planting function evaluation was carried out considering the park function setting, planting concept according to spatial function, and planting status. As a result of the study, the direction of planting renewal according to functional change was derived for each stage of planting function evaluation. Increasing the green area ratio is a priority in setting up park functions, but user convenience should also be considered. As a concept of planting, visual landscape planting involves planting species with beautiful tree shapes, high carbon absorption, and fine dust reduction effects. Ecological landscape planting should create a multi-layered planting site on a slope. Buffer planting should be created as multi-layered forests to improve carbon absorption and fine dust reduction effects. Green planting should consist of broad-leaved trees and herbaceous layers and aim for the natural planting of herbaceous species. For plant species, species with high urban environment improvement effects, local native species, and wild bird preferred species should be selected. As for the planting structure, landscape planting sites and green planting sites should be composed of trees, shrubs, and trees and herbaceous layers that emphasize ecology or require multi-layered buffer functions. A higher standard is applied based on the planting interval for planting density. Installing a rainwater recycling facility and using soil loam for the planting base improves performance. The results of this study are meaningful in that they can be applied to derive areas needing functional improvement by performing planting function evaluation when planning planting renewal of aging urban parks and can suggest renewal directions that reflect the paradigm of functional change of created green areas.

• Korean Journal of Social Welfare Studies
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• v.42 no.4
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• pp.239-262
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• 2011

The Korean government's recent large-scale termination and modification of welfare benefits revealed a procedural problem under the National Basic Living Security Act. Under the Act, welfare recipients have a legal right to make complaints only after the termination or modification is enforced; the Act fails to provide the recipients with an opportunity for a hearing before termination or modification, and this creates serious threats to the recipients, whose livelihoods are dependent on welfare benefits. Korean jurisprudence has adopted the due process of law principle. The principle originated from the due process in US jurisprudence, and Korea has applied it broadly to any government actions that restrict individuals' constitutional or legal rights. This paper reviews the termination or modification procedure under the Act with the lens of the due process principle and criticizes that the current law is not in compliance with the principle. In supporting that such termination and modification procedure infringes on welfare recipients' protected rights, this paper discusses two theories as to what rights are protected. First, termination or modification of welfare benefits can be considered as deprivation of property. The 'property' theory may be weak under Korean jurisprudence, because the concept of property under the Korean Constitution is narrowly construed. Second, this paper relies on the constitutional provision that recognizes "the right to a life worthy of human beings," which requires the State to guarantee minimum standard of living for all. As welfare recipients are deemed to receive benefits as a right under the Constitution, any deviation from the minimum requirement would constitute a violation of constitutional rights. In any case, termination or modification of welfare benefits that are concretized under the Act should be protected under the due process principle, because the principle would cover any government actions that restrict established legal rights. This paper argues that the procedural due process requires the recipients be guaranteed an opportunity to have a hearing before the termination or modification is enforced. An independent decision-maker should hear the proceedings, and the recipients should have an option to orally present their opinions in front of the decision-maker. The hearing process under the Administrative Procedures Act of Korea offers elements that would satisfy these procedural requirements. Thus, this paper concludes that the National Basic Living Security Act should be amended to adopt the hearing process under the Administrative Procedures Act in its termination and modification procedure.

• Asia Marketing Journal
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• v.7 no.3
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• pp.53-76
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• 2005

With rapid technological and market change, new product development (NPD) complexity is a significant issue that organizations continually face in their development projects. There are numerous factors, which cause development projects to become increasingly costly & complex. A product is more likely to be successfully developed and marketed when the complexity inherent in NPD projects is clearly understood and carefully managed. Based upon the previous studies, this study examines the nature and importance of complexity in developing new products and then identifies several issues in managing complexity. Issues considered include: definition of complexity : consequences of complexity; and methods for managing complexity in NPD projects. To achieve high performance in managing complexity in development projects, these issues need to be addressed, for example: A. Complexity inherent in NPD projects is multi-faceted and multidimensional. What factors need to be considered in defining and/or measuring complexity in a development project? For example, is it sufficient if complexity is defined only from a technological perspective, or is it more desirable to consider the entire array of complexity sources which NPD teams with different functions (e.g., marketing, R&D, manufacturing, etc.) face in the development process? Moreover, is it sufficient if complexity is measured only once during a development project, or is it more effective and useful to trace complexity changes over the entire development life cycle? B. Complexity inherent in a project can have negative as well as positive influences on NPD performance. Thus, which complexity impacts are usually considered negative and which are positive? Project complexity also can affect the entire organization. Any complexity could be better assessed in broader and longer perspective. What are some ways in which the long-term impact of complexity on an organization can be assessed and managed? C. Based upon previous studies, several approaches for managing complexity are derived. What are the weaknesses & strengths of each approach? Is there a desirable hierarchy or order among these approaches when more than one approach is used? Are there differences in the outcomes according to industry and product types (incremental or radical)? Answers to these and other questions can help organizations effectively manage the complexity inherent in most development projects. Complexity is worthy of additional attention from researchers and practitioners alike. Large-scale empirical investigations, jointly conducted by researchers and practitioners, will help gain useful insights into understanding and managing complexity. Those organizations that can accurately identify, assess, and manage the complexity inherent in projects are likely to gain important competitive advantages.

• Economic and Environmental Geology
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• v.56 no.6
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• pp.781-797
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• 2023

Recently, there has been a rapid response from mineral-demanding countries for securing critical minerals in a high tech industries. Graphite, while overwhelmingly dominated by China in production, is changing in global supply due to the exponential growth in EV battery sector, with active exploration in East Africa. Rare earth elements are essential raw materials widely used in advanced industries. Globally, there are ongoing developments in the production of REEs from three main deposit types: carbonatite, laterite, and ion-adsorption clay types. While China's production has decreased somewhat, it still maintains overwhelming dominance in this sector. Recent changes over the past few years include the rapid emergence of Myanmar and increased production in Vietnam. Nickel has been used in various chemical and metal industries for a long time, but recently, its significance in the market has been increasing, particularly in the battery sector. Worldwide, nickel deposits can be broadly classified into two types: laterite-type, which are derived from ultramafic rocks, and ultramafic hosted sulfide-type. It is predicted that the development of sulfide-type, primarily in Australia, will continue to grow, while the development of laterite-type is expected to be promoted in Indonesia. This is largely driven by the growing demand for nickel in response to the demand for lithium-ion batteries. The global lithium ores are produced in three main types: brine lake (78%), rock/mineral (19%), and clay types (3%). Rock/mineral type has a slightly higher grade compared to brine lake type, but they are less abundant. Chile, Argentina, and the United States primarily produce lithium from brine lake deposits, while Australia and China extract lithium from both brine lake and rock/mineral sources. Canada, on the other hand, exclusively produces lithium from rock/mineral type. Vanadium has traditionally been used in steel alloys, accounting for approximately 90% of its usage. However, there is a growing trend in the use for vanadium redox flow batteries, particularly for large-scale energy storage applications. The global sources of vanadium can be broadly categorized into two main types: vanadium contained in iron ore (81%) produced from mines and vanadium recovered from by-products (secondary sources, 18%). The primary source, accounting for 81%, is vanadium-iron ores, with 70% derived from vanadium slag in the steel making process and 30% from ore mined in primary sources. Intermediate vanadium oxides are manufactured from these sources. Vanadium deposits are classified into four types: vanadiferous titanomagnetite (VTM), sandstone-hosted, shale-hosted, and vanadate types. Currently, only the VTM-type ore is being produced.

• Korea Trade Review
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• v.48 no.3
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• pp.217-242
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• 2023

This study aims to analyze the factors influencing the logistics demand of inland ports along the Yangtze River and predict future port logistics demand based on these factors. The logistics demand prediction using system dynamics techniques was conducted for a total of six ports, including Chongqing and Yibin ports in the upper reaches, Jingzhou and Wuhan ports in the middle reaches, and Nanjing and Suzhou ports in the lower reaches of the Yangtze River. The logistics demand for all ports showed an increasing trend in the mid-term prediction until 2026. The logistics demand of Chongqing port was mainly influenced by the scale of the hinterland economy, while Yibin port appeared to heavily rely on the level of port automation. In the case of the upper and middle reach ports, logistics demand increased as the energy consumption of the hinterland increased and the air pollution situation worsened. The logistics demand of the middle reach ports was greatly influenced by the hinterland infrastructure, while the lower reach ports were sensitive to changes in the urban construction area. According to the sensitivity analysis, the logistics demand of ports relying on large cities was relatively stable against the increase and decrease of influential factors, while ports with smaller hinterland city scales reacted sensitively to changes in influential factors. Therefore, a strategy should be established to strengthen policy support for Chongqing port as the core port of the upper Yangtze River and have surrounding ports play a supporting role for Chongqing port. The upper reach ports need to play a supporting role for Chongqing port and consider measures to enhance connections with middle and lower reach ports and promote the port industry. The development strategy for inland ports along the Yangtze River suggests the establishment of direct routes and expansion of the transportation network for South Korean ports and stakeholders. It can suggest expanding the hinterland network and building an efficient transportation system linked with the logistics hub. Through cooperation, logistics efficiency can be enhanced in both regions, which will contribute to strengthening the international position and competitiveness of each port.

• Journal of the Korea institute for structural maintenance and inspection
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• v.27 no.6
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• pp.152-161
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• 2023

In general, large-capacity hydrogen storage vessels, typically in the form of vertical cylindrical vessels, are constructed using steel materials. These vessels are anchored to foundation slabs that are specially designed to suit the environmental conditions. This anchoring method involves pre-installed anchors on top of the concrete foundation slab. However, it's important to note that such a design can result in concentrated stresses at the anchoring points when external forces, such as seismic events, are at play. This may lead to potential structural damage due to anchor and concrete damage. For this reason, in this study, it selected an vertical hydrogen storage vessel based on site observations and created a 3D finite element model. Artificial seismic motions made following the procedures specified in ICC-ES AC 156, as well as domestic recorded earthquakes with a magnitude greater than 5.0, were applied to analyze the structural behavior and performance of the target structures. Conducting experiments on a structure built to actual scale would be ideal, but due to practical constraints, it proved challenging to execute. Therefore, it opted for an analytical approach to assess the safety of the target structure. Regarding the structural response characteristics, the acceleration induced by seismic motion was observed to amplify by approximately ten times compared to the input seismic motions. Additionally, there was a tendency for a decrease in amplification as the response acceleration was transmitted to the point where the centre of gravity is located. For the vulnerable components, specifically the sub-system (support columns and anchorages), the stress levels were found to satisfy the allowable stress criteria. However, the concrete's tensile strength exhibited only about a 5% margin of safety compared to the allowable stress. This indicates the need for mitigation strategies in addressing these concerns. Based on the research findings presented in this paper, it is anticipated that predictable load information for the design of storage vessels required for future shaking table tests will be provided.