• Ecology and Resilient Infrastructure
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• v.9 no.4
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• pp.228-236
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• 2022

Riverbank revetments are installed to increase the stability, while preventing scouring, and utilize the rivers; their construction is prioritized to secure dimensional safety that can withstand flooding. Existing revetment technologies employ use of rocks, gabions, and concrete. However, stone and gabions are easily erosion and destroyed by extensive flooding. Though the materials used in concrete technology possess strength and stability, the strong base adversely affects the aquatic ecosystem as components leach and remain in water for a long time. This serves as an environmental and ecological issue as vegetation does not grow on the concrete surface. This study introduces multi-layer porous riverbank revetment technology using biopolymer materials extracted from castor oil. Results obtained from this study suggest that this technology provides greater dimensional stability as compared to existing technologies. Moreover. it does not release toxic substances into the rivers. Multiple experiments conducted to review the application of this technology to diverse river environments confirm that stability is achieved at a flow velocity of 8.0 m/s and maximum tractive force of 67.25 kg_f/m² (659.05 N/m²).

• Journal of the Korean Society of Marine Environment & Safety
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• v.29 no.5
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• pp.505-511
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• 2023

In the present study, a deep learning model was established to predict the motion response of small fishing vessels. Hydrodynamic performances were evaluated for two small fishing vessels for the dataset of deep learning model. The deep learning model of the Long Short-Term Memory (LSTM) which is one of the recurrent neural network was utilized. The input data of LSTM model consisted of time series of six(6) degrees of freedom motions and wave height and the output label was selected as the time series data of six(6) degrees of freedom motions. The hyperparameter and input window length studies were performed to optimize LSTM model. The time series motion response according to different wave direction was predicted by establised LSTM. The predicted time series motion response showed good overall agreement with the analysis results. As the length of the time series increased, differences between the predicted values and analysis results were increased, which is due to the reduced influence of long-term data in the training process. The overall error of the predicted data indicated that more than 85% of the data showed an error within 10%. The established LSTM model is expected to be utilized in monitoring and alarm systems for small fishing vessels.

• Korean Security Journal
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• no.14
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• pp.465-484
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• 2007

Our society's modernization created many opportunities for us to need a private investigation service system. Variation of international environment due to joining in the OECD, opportunity of individual legal, collect evidence during judgement, prevention of damage criminal, security of business in company, free trade economy's system etc and don't need to enumerate how important of introduction of private investigation service system. In addition to there are lots of objection opinions, such as possibility of person's private life, invade of lawyer's area, confliction with investigation team, gap of wealth and poverty that make preponderance of information. So this research can be considerate from objective opinion, and can obtain conclusion just like below. First, private detective agencies that encroach on the individual rights will naturally deteriorate after the implementation of private investigation service system. Through this, the probability of civil rights encroachment will be lower, and for this to happen there needs to be a thorough maintenance of the system. Secondly, mutually beneficial solution should be found not by a conflict between two sides. Detective business sector should not cause social confusion from conflicts with other investigation organization such as police, or investigators, rather, it must get on the demand of the diversified citizen and maintain the diverse sector inter-cooperate right, and to do that law and institution must be made for the base. Thirdly, investigation used depending on the gap between wealth and poverty does not mean the actualization of the rights and interests of the citizen. If the duty of investigation sector is to find the evidence and collect or manufacture of the evidence, then the problems which the nation can't handle will be more enlarged and then finally end up with strengthening the capability of national public security demand.

• Land and Housing Review
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• v.3 no.2
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• pp.127-136
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• 2012

The Korean government designated 10 innovation cities throughout the country in 2005 in order to resolve concentration on the capital region and to promote balanced development of localities. An innovation city is a future-type city equipped with environment for innovation and high-quality settlement environment in terms of residence, education and culture by accommodating public institutions and facilitating close cooperation among companies, universities and research institutes. Thus, for the early settlement and activation of innovation cities, this study suggested a plan to operate the current innovation city business centers from a mid- and long-term viewpoint rather than for a limited time. Through this study, we attempt to establish the roles of the centers so that they can play central roles in the move of public institutions, the development of industry-university-research institute clusters, the creation of innovations, and the spread of innovations, which are the goals of the development of public institutions, after the sites have been prepared.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.33 no.6
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• pp.383-390
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• 2020

Since the dynamic behaviors of liquid storage tanks on flexible soil are significantly influenced by the fluid-structure-soil interaction (FSSI), its effects must be rigorously considered for accurate earthquake analysis and seismic design of the storage system. In this study, dynamic analysis is performed for a rectangular liquid storage tank on flexible soil, and its dynamic characteristics are examined by rigorously considering the effects of FSSI. The hydrodynamic force and the interaction force between the structure and soil are evaluated using the finite-element approach. In the evaluations, mid-point integrated finite elements and viscous dampers are considered for energy radiation into the infinite soil. The effective earthquake force is then obtained from free-field analysis. It is thus demonstrated that the earthquake responses of the rectangular liquid storage tank on flexible soil are significantly influenced by the FSSI.

• Membrane Journal
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• v.31 no.3
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• pp.212-218
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• 2021

It is inevitable to generate incomplete combustion gases when mankind utilizes fossil fuels. From this point of view, gas separation process of combustion gas suggests the possibility of recycling CO gas. In this study, we fabricated a facilitated transport polymeric composite membrane for CO separation using AgBF₄ and HBF₄. The copolymer was synthesized via free-radical polymerization of poly(vinyl alcohol) (PVA) as a main chain and acrylic acid (AA) monomer as a side chain. The polymer synthesis was confirmed by FT-IR and the interactions of graft copolymer with AgBF₄, and HBF₄ were characterized by TEM. PVA-g-PAA graft copolymer membranes showed good channels for facilitated CO transport. In this perspective, we suggest the novel approach in CO separation membrane area via combination of grafting and facilitated transport.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.49 no.1
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• pp.59-65
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• 2023

We validated the physiological activity of Syzygium claviflorum (Roxb.) Wall. ex A.M. Cowan & Cowan (S. claviflorum) extracts (leaves, stems, fruits, and flowers) as a cosmetic ingredient. Firstly, S. claviflorum extracts removed over 80% of free radicals at various concentrations in antioxidant experiments using the DPPH and ABTS assay. In cytotoxicity experiments using human epidermal keratinocytes, S. claviflorum extracts showed low cytotoxicity. In addition, S. claviflorum extracts significantly increased the expression of keratin (KRT)1, KRT2, KRT9, KRT10, which are differentiation markers of keratinocytes, as well as genes involved in the maintenance of skin barrier function, including involucrin (IVL), loricrin (LOR), filaggrin (FLG), and claudin1 (CLDN1). In particular, the expression of FLG protein, inhibited by interleukin (IL)-4/IL-13 in atopic dermatitis, was restored by S. claviflorum extracts in in vitro experiments. Therefore, S. claviflorum extracts with excellent antioxidant efficacy and skin barrier improvement function will be useful materials for the development of future atopic dermatitis treatments and cosmetics.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.37 no.1
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• pp.9-16
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• 2024

Using the proper orthogonal decomposition (POD) based intrusive reduced order model (ROM), the total degrees of freedom of the structural system can be significantly reduced and the critical time step satisfying the conditional stability increases in the explicit time integrations. In this study, therefore, the changes in the critical time step in the explicit time integrations are investigated using both the POD-ROM and Voronoi-cell lattice model (VCLM). The snapshot matrix is composed of the data from the structural response under the arbitrary dynamic loads such as seismic excitation, from which the POD-ROM is constructed and the predictive capability is validated. The simulated results show that the significant reduction in the computational time can be achieved using the POD-ROM with sufficiently ensuring the numerical accuracy in the seismic analyses. In addition, the validations show that the POD based intrusive ROM is compatible with the Voronoi-cell lattice based explicit dynamic analyses. In the future study, the research results will be utilized as an elemental technology for the developments of the real-time predictive models or monitoring system involving the high-fidelity simulations of structural dynamics.

• Journal of the Korean Society for Library and Information Science
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• v.48 no.2
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• pp.89-107
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• 2014

The purposes of this study are to analyze the effectiveness of public library reading programs for children in qualitative way and to apply the outcomes to identify areas to measure the success of library reading programs. Interviews were conducted with children who participated in '2013 Reading Books with Libraries' program and adults who were in charge of managing the program. Observations on the program were also conducted. The findings indicate that children who participated in '2013 Reading Books with Libraries' program positively changed in various aspects. Selected areas to measure the success of library reading programs include: reading behavior; attitude to books; awareness of libraries and librarians; participation of library reading programs; the ability to read aloud; the ability to comprehend stories by listening; aggression; the ability to express one's own feelings; speech ability; concentration power; and undiscovered potential. The elements that affect the success or failure of library reading programs include: librarian's enthusiasm on running the reading program; environmental condition of the community child care center; age differences between child participants; running style of the instructor's program; selection of books; child participants' reading abilities and interests in reading; available time for free voluntary reading.

• Vending industry
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• v.1 no.3 s.3
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• pp.96-99
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• 2001

사회생활을 하는 사람이라면 하루에 꼭 한번 정도는 하는 일이 있다. 출퇴근, 회의, 그리고 자판기 이용이 그것이다. 이른아침 출근을 위해 지하철 무인 패스 판매기를 이용하고 출근해서는 나른한 오후시간을 깨우기위해 으례 커피자판기를 이용하기 일수이고 여가시간을 이용해서는 친구들과 가벼운 스티커 사진촬영을 하는 등 우리의 자판기 이용 문화는 이미 현대인 너무나도 보편화되고 친숙해져버린 생활의 한 단면이 되어버렸다. 그렇다면 자판기는 언제쯤 인간의 일상사 속에 등장하기 시작했을까? 놀랍게도 자판기의 기원은 기원전 215년으로 거슬러 올라간다. 당시 이집트 사원에서 `성수(聖水)`를 판매하기 위해 만들어졌던 동전식 조작장치가 최초의 자판기라는게 정설로 받아들여온 사실로서 동전을 넣으면 투입된 동전이 받치고 있던 접시가 기울어져 그 기울기가 원래대로 돌아올 때까지 출구로 물이 나오는 원리를 이용한 것이다. 누가 만든것인지는 명확히 밝혀지지 않았으나 확실한 것은 자판기의 역사가 이미 기원전으로 거슬러 올라가고 인간생활에 뿌리내린 역사가 깊다는 것이다. 아무튼 이렇게 자판기가 나타난 이래로 17세기에 키산드리아 과학자 헤론이 쓴 책이 발견되기 이전까지 자판기는 잊혀진 발명품이었다. 그러나 그 책의 발견과 함께 사람들은 옛문헌 속의 발명품의 실용성에 관심을 기울이기 시작했고 차츰 영국의 선술집과 여관 담배 자판기가 등장하기 시작했으며 자판기는 식민지까지 보급될 정도로 선풍적인 인기를 끌었다. 19세기에 들어서는 담배 이외의 물건을 판매할 수 있는 자판기에 관심을 두기 시작했고, 자유주의 사상이 풍미하던 시절, 영국에서 나타난 금서(禁書)자판기에서부터 상업문화가 발달한 미국의 껌볼 자판기에 이르기까지 자판기는 점차로 그 영역을 넓혀갔고 또한 발전해 왔던 것이다. 그러나 자동판매기의 이러한 급속한 발전과 소비영역에서 역량의 강화는 비단 단순한 소비패턴의 변화에서 기인하는 것이라고는 보기 어렵다. 이는 노동집약적 산업구조에서 기술집약적 산업사회로의 전환에 따른 대량생산, 대량소비, 소비패턴 변화 등의 마케팅 환경의 변화에 따라 새로운 유통구조의 출현이 요망되었기 때문이었다. 따라서 슈퍼마켓, 쇼핑센터 등의 새로운 유통구조의 출현 외에도 인건비의 상승, 장소의 제한 및 구입의 편리성 등에 따라 무인 자동판매기의 등장은 필연적이었다고 볼수 있다. 이후 자판기의 판매상품의 범위는 더욱 넓어졌고 컵라면, 인형, 마음에 드는 음악만을 골라담는 CD,휴지,구두광택기,사진스티커,콘돔,장난감,담배,여행용품,스낵,아이스크림 등등 소액권과 손가락만 있으면 살 수 있는 물건의 가짓수는 헤아리기 어려울 정도가 되었으며, 그만큼 유통혁신의 기구로서 산업에 미치는 영향 역시 증대되고 있으며, 이러한 경향은 21세기 정보화,첨단화 경향에 발맞추어 더욱 진보된 형태로 발전해오고 있다.