• Journal of the Korea Institute of Building Construction
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• v.7 no.2 s.24
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• pp.85-92
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• 2007

In the past, recycled aggregate was used very limitedly in low value-added areas such as the base layer of roads. However, in response to the shortage of natural aggregate, high consciousness of resource saving and changed idea on environment, the quality of recycled aggregate has been improved considerably, and the percentage of recycled construction waste is increasing every year compared to simple landfill or incineration. Recently the Act on the Promotion of Construction Waste Recycling was enacted on December 2003 for the efficient use of recycled aggregate, and the Standards for the Quality of Recycled Aggregate for Concrete (Proposal) were announced in order to use and manage recycled aggregate according to quality. According to the Standards for the Quality of Recycled Aggregate for Concrete (Proposal), it is recommended to substitute recycled coarse aggregate and fine aggregate below 30% each. However, compared to the trend of recycling, the recycling rate of aggregate is still quite low. It is because of low performance of recycled aggregate, users' lack of understanding, etc. These problems basically come from the decrease of strength of recycled concrete resulting from the use of recycled aggregate, and recycled aggregate is still considered not reliable because there have been not many cases of actual application. If the basic problem of strength decrease is solved and data on recycled aggregate is provided through actual field placing, we may maximize the use of recycled aggregate. Thus, in order to maximize the use of recycled aggregate that satisfy the recycled aggregate quality standards, the present study made a mock-up similar to real structures, evaluated its performance and examined the field applicability of recycled aggregate concrete.

• Natural Product Sciences
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• v.14 no.1
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• pp.21-26
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• 2008

The leaves of Acanthopanax species have traditionally been used as a tonic and a sedative as well as in the treatment of rheumatism and diabetes. Chiisanoside is the major active lupane triterpenoid of Acanthopanax leaves. To investigate the bioactivities of chiisanoside, which act on bone metabolism, the effects of chiisanoside on the function of osteoblastic MC3T3-E1 cells were studied. Chiisanoside $(0.02{\sim}20\;{\mu}M)$ significantly increased the growth of MC3T3-E1 cells and caused a significant elevation of alkaline phosphatase (ALP) activity, collagen content, and nodules mineralization in the cells (P < 0.05). The effect of chiisanoside (2 ${\mu}M$) in increasing ALP activity was completely prevented by the presence of tamoxifen, suggesting that the effect of chiisanoside might be partly estrogen receptor mediated. Moreover, cotreatment of p38 inhibitor SB203580 or JNK inhibitor SP600125 inhibited chiisanoside-mediated ALP upregulation, suggesting that the induction of differentiation by chiisanoside is associated with increased activation of p38 and JNK mitogen-activated protein kinases. Our data indicate that the enhancement of osteoblast function by chiisanoside may result in the prevention for osteoporosis.

• 한국방재학회:학술대회논문집
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• 2008.02a
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• pp.135-138
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• 2008

As the procedure of the close examination of disaster impact at the initial stage of the beginning of development plans, the newly extablished Pre Disaster Impact Assessment Review Deliberation (PDIARD) system which have been introduced through the revision of the Natural Disaster Countermeasure Act-revised at August, 2005 is enforced for the purpose of the disaster prevention which caused during a development projects. From that time down to this day, the PDIARD system have been reviewed about 6,000 cases totally. However, the current the PDIARD system at the uppermost limit in the aspect of every Acts and operational problems is in need of sustaining supplementation at the present situation. To cope with this operational remedy related to the PDIARD system, this study deals in 3 major concerns. First, it is required to fix a criterion in detail because of a wide range of the subject plans of deliberation. Second, there is some ambiguity according to the area or length of the subjected administrative and development plans. So it should be excepted of the targeted plans which has few probability in disaster potential or vulnerability. Finally, the subjected plans need to be added as to the continuous urbanization and industrialization and the enactment or revision of the Acts related. This study focuses on the investigation and analysis to find out the improvement way about the main problem pending of the PDIARD system, consequently suggests a effective remedy and new categories, including future directions and detailed plans for operation.

• Journal of the Architectural Institute of Korea Planning & Design
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• v.34 no.12
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• pp.145-156
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• 2018

This study explores changes of industrial scales and building activities in the semi-industrial area of Seoul's Seong-su, responding to the shifts of industrial structures and policies in the Korean society. The purpose of this study is to investigate patterns of construction activities of factory buildings in the Seong-su semi-industrial area by analyzing changes in industrial facilities. As a result of the analysis, the change of the factory building area come out from the recent survey implies the possibility of entrepreneurial inflow as much and the new constructions and some remodeling cases which are characterized by complexity seem to correspond to the industrial structure. However, it is unreasonable to believe that this phenomenon is a mainstream movement involving small-scale factory buildings and companies. This is because there are aspects that are not included in this movement, such as changing the use of buildings without accompanying physical changes. On the other hand, compared to various movements of individual companies in response to the industrial structure, the physical plan suggests a limited alternative centering on the floor area ratio and the building area ratio. This means that the efforts to attract and grow the power of knowledge based-industry through the designation of the Industrial Development Promotion District in part of the case sites, overlook the natural change through remodeling and reuse of existing buildings. In addition, considering the fact that the production space of industrial use can be greatly influenced by the behavior of users compared to general buildings such as residential and commercial, it is necessary to pay attention to various phenomena occurring in the area more locally than the uniform supply policy. Based on these findings, this study contributes to illuminate the legal system related to building act in the Seong-su semi-industrial area and the potential direction of architectural suggestions in related policies and researches.

• Journal of Industrial Convergence
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• v.19 no.6
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• pp.139-144
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• 2021

Since the human act to pursue beauty is the most natural desire and instinct, the demand for a new beauty trend in line with the 4th industrial revolution era, in which aesthetic interest in human appearance management along with the importance of appearance is increasing day by day is very necessary at this time. In order to derive the source from art, which is closely related to beauty studies, the shape and texture of women's hair design appearing in 'Chinoiserie' style Western paintings that were popular in Europe and France in the 18th century. As a result of the study, the hair design of women appearing in four Western paintings showed characteristics of each individual shape, texture, and color. Through this study, the foundation stone for the development of a new mode hairstyle for modern people living in a rapidly changing era while quarreling with the village, and the foundation stone for the development of various beauty contents.

• Journal of Preventive Medicine and Public Health
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• v.56 no.1
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• pp.1-11
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• 2023

In 1945, atomic bombs were dropped on Hiroshima and Nagasaki. Approximately 70 000 Koreans are estimated to have been exposed to radiation from atomic bombs at that time. After Korea's Liberation Day, approximately 23 000 of these people returned to Korea. To investigate the long-term health and hereditary effects of atomic bomb exposure on the offspring, cohort studies have been conducted on atomic bomb survivors in Japan. This study is an ongoing cohort study to determine the health status of Korean atomic bomb survivors and investigate whether any health effects were inherited by their offspring. Atomic bomb survivors are defined by the Special Act On the Support for Korean Atomic Bomb Victims, and their offspring are identified by participating atomic bomb survivors. As of 2024, we plan to recruit 1500 atomic bomb survivors and their offspring, including 200 trios with more than 300 people. Questionnaires regarding socio-demographic factors, health behaviors, past medical history, laboratory tests, and pedigree information comprise the data collected to minimize survival bias. For the 200 trios, whole-genome analysis is planned to identify de novo mutations in atomic bomb survivors and to compare the prevalence of de novo mutations with trios in the general population. Active follow-up based on telephone surveys and passive follow-up with linkage to the Korean Red Cross, National Health Insurance Service, death registry, and Korea Central Cancer Registry data are ongoing. By combining pedigree information with the findings of trio-based whole-genome analysis, the results will elucidate the hereditary health effects of atomic bomb exposure.

• Ecology and Resilient Infrastructure
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• v.7 no.3
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• pp.171-180
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• 2020

With the increase in industrialization and urbanization, scarcity of space for leisure life has become an important issue. Opportunities such as natural scenery and ecological experiences provided by waterfront spaces around streams are fundamental factors in the development of the community and creation of a hydrophilic park. In the past, on-site surveys have been conducted using human resources to quantify the number of river visitors, but the accuracy of the results was not sufficient owing to limitations in expenses, manpower, space, and time. In this study, to overcome this problem, we estimated the number of visitors using the location information related to hydrophilic parks. The study areas were Samrak Ecological Park and Daejeo Ecological Park located downstream of the Nakdong River. We compared and analyzed the pattern of the visitors by using the large communication data and the visiting pattern based on GPS location information. The GPS location information is based on Google Popular Times and Kakao visitor data. When the GPS location data were used, the pattern for weekday and weekend visitors was clearer than when the large communication data were used. Therefore, it is expected to be similar to the result of GPS location information if the number of visitors is extracted under the condition of precision of pCELL size and residence time of 30 minutes or more when using future communication big data. In addition, if revisions such as the Personal Information Protection Act are made to extract more accurate data, by estimating the number of visitors based on GPS data, more accurate indicators of the number of visitors can be derived.

• Korean Journal of Environment and Ecology
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• v.36 no.3
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• pp.318-326
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• 2022

The Convention on Biodiversity (CBD) recommends that 17% of the land be designated as a protected area to counter global environmental problems. Korea also realized a need to designate protected areas according to the international level and explain the significance of designating protected areas. Accordingly, studies on ecosystem services are required. In Korea, the protected areas are designated as national parks, provincial parks, and county parks by hierarchy under the Natural Parks Act. However, as priority was on political and administrative aspects, research on ecosystem service value evaluation and habitat management were concentrated in national parks, and provincial and county parks were relatively neglected. Therefore, more studies on provincial and county parks are necessary. In this study, habitat quality for Gajisan Provincial Park, where there were few studies on habitat management and ecosystem service valuation, was evaluated using the InVEST Habitat Quality model among the InVEST models. The analysis results were compared with 16 mountainous national parks. The results showed that the habitat quality value of Gajisan Provincial Park was 0.83, higher than that of the surrounding areas. The analysis of habitat quality in three districts showed 0,84 for the Tongdosa and Naewonsa districts and 0.83 for the Seoknamsa district. By use district, the nature conservation district, the natural environment district, the cultural heritage district, and the park village district had the highest habitat quality value in that order. Compared with the existing habitat quality analysis results of national parks, Gajisan Provincial Park showed naturalness at the level of Mudeungsan National Park. These results can be used as objective data for establishing policies and management plans to preserve biodiversity and promote ecosystem services in provincial parks.

• Journal of Korean Society of Forest Science
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• v.77 no.1
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• pp.17-22
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• 1988

Inhibitory effect of L. leptolepis fallen leaf extracts on the germination of Pinus densiflora, ${\times}$ Pinus rigitaeda, Pinus rigida, Pinus thunbergii and Larix leptolepis was investigated. Germination of those seeds in culture room and in pot at field showed the highly significant inhibitory effects by the aqueous extracts from L. leptolepis fallen leaves. Among them L. leptolepis was the most severely inhibited by the aqueous extracts used. To identify allelopathic substances, thin-layer chromatography was employed. Gallic, ferulic, t-cinnamic and vanillic acids were identified from fallen leaves of L. leptolepis. From the results, it is assumed that autotoxicity of L. leptolepis may act as inhibitory factors on germination of the species in natural stands.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.33 no.12
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• pp.1401-1409
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• 2009

All the forces in the real world act dynamically on structures. Design and analysis should be performed based on the dynamic loads for the safety of structures. Dynamic (transient or vibrational) responses have many peaks in the time domain. Topology optimization, which gives an excellent conceptual design, mainly has been performed with static loads. In topology optimization, the number of design variables is quite large and considering the peaks is fairly costly. Topology optimization in the frequency domain has been performed to consider the dynamic effects; however, it is not sufficient to fully include the dynamic characteristics. In this research, linear dynamic response topology optimization is performed in the time domain. First, the necessity of topology optimization to directly consider the dynamic loads is verified by identifying the relationship between the natural frequency of a structure and the excitation frequency. When the natural frequency of a structure is low, the dynamic characteristics (inertia effect) should be considered. The equivalent static loads (ESLs) method is proposed for linear dynamic response topology optimization. ESLs are made to generate the same response field as that from dynamic loads at each time step of dynamic response analysis. The method was originally developed for size and shape optimizations. The original method is expanded to topology optimization under dynamic loads. At each time step of dynamic analysis, ESLs are calculated and ESLs are used as the external loads in static response topology optimization. The results of topology optimization are used to update the design variables (density of finite elements) and the updated design variables are used in dynamic analysis in a cyclic manner until the convergence criteria are satisfied. The updating rules and convergence criteria in the ESLs method are newly proposed for linear dynamic response topology optimization. The proposed updating rules are the artificial material method and the element elimination method. The artificial material method updates the material property for dynamic analysis at the next cycle using the results of topology optimization. The element elimination method is proposed to remove the element which has low density when static topology optimization is finished. These proposed methods are applied to some examples. The results are discussed in comparison with conventional linear static response topology optimization.