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Acanthamoeba in Southeast Asia - Overview and Challenges

  • Bunsuwansakul, Chooseel;Mahboob, Tooba;Hounkong, Kruawan;Laohaprapanon, Sawanya;Chitapornpan, Sukhuma;Jawjit, Siriuma;Yasiri, Atipat;Barusrux, Sahapat;Bunluepuech, Kingkan;Sawangjaroen, Nongyao;Salibay, Cristina C.;Kaewjai, Chalermpon;Pereira, Maria de Lourdes;Nissapatorn, Veeranoot
    • Parasites, Hosts and Diseases
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    • v.57 no.4
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    • pp.341-357
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    • 2019
  • Acanthamoeba, one of free-living amoebae (FLA), remains a high risk of direct contact with this protozoan parasite which is ubiquitous in nature and man-made environment. This pathogenic FLA can cause sight-threatening amoebic keratitis (AK) and fatal granulomatous amoebic encephalitis (GAE) though these cases may not commonly be reported in our clinical settings. Acanthamoeba has been detected from different environmental sources namely; soil, water, hotspring, swimming pool, air-conditioner, or contact lens storage cases. The identification of Acanthamoeba is based on morphological appearance and molecular techniques using PCR and DNA sequencing for clinico-epidemiological purposes. Recent treatments have long been ineffective against Acanthamoeba cyst, novel anti-Acanthamoeba agents have therefore been extensively investigated. There are efforts to utilize synthetic chemicals, lead compounds from medicinal plant extracts, and animal products to combat Acanthamoeba infection. Applied nanotechnology, an advanced technology, has shown to enhance the anti-Acanthamoeba activity in the encapsulated nanoparticles leading to new therapeutic options. This review attempts to provide an overview of the available data and studies on the occurrence of pathogenic Acanthamoeba among the Association of Southeast Asian Nations (ASEAN) members with the aim of identifying some potential contributing factors such as distribution, demographic profile of the patients, possible source of the parasite, mode of transmission and treatment. Further, this review attempts to provide future direction for prevention and control of the Acanthamoeba infection.

A Study on the Improvement and the Survey Study on the Complaints of People with Disabilities in the Use of Disabled Car (복지차 이용 시 장애인의 불편사항 조사와 개선방안 연구)

  • Rhee, Kum Min;Kim, Dong Ok
    • 재활복지
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    • v.17 no.4
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    • pp.339-370
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    • 2013
  • This study is to suggest necessary improvements of inconvenient elements as well as the ergonomic design standard to develop disabled cars by evaluating the types of needs and observing the behavior characteristics on their car use and the survey on the complaints of the disabled drivers and their guardians in the use of disabled car. The results of this study are as follows. First, both the disabled drivers and their guardians are found to feel high inconvenience and low satisfaction with the cars they use now. Second, the disabled owner-drivers also answered in a same way as guardians. They find the most difficulty in moving the supporting equipment to get into and out of a car. Both the owner-drivers with disabilities and guardians complained of lack of handiness they face when they wear the seat belts and sitting on the seats. In view of this, a disabled car to be developed should have ergonomic design for its seats and the safety of the seatbelt as well as trouble-free supporting equipment helping them move. Third, rather than owner-drivers with handicaps, guardians expressed more difficulties and less contentment with the cars for the disabled, which is reckoned to lead to the changes of perspectives on development of cars for the disabled breaking away from existing viewpoints focusing on the accessibility to the vehicles. Fourth, both owner-drivers and guardians showed higher interests in driving and other safety and convenience measures than in using supporting equipment to get into and out of vehicles, implying that rather than the accessibility to get into and out of a car, convenience should primarily be taken into account for the design of the disabled car. Fifth, the auto-manufacturer is to give prior thought to user convenience when developing a car in practice. For this, the developer may have the disabled car users join the process of development as well as asking experts for help and participation.

Fabrication of Polymeric Blend Membranes Using PBEM-POEM Comb Copolymer and Poly(ethylene glycol) for CO2 Capture (PBEM-POEM 공중합체와 Poly(ethylene glycol)의 폴리머 블렌드를 이용한 이산화탄소 분리막 제조)

  • Moon, Seung Jae;Min, Hyo Jun;Kim, Na Un;Kim, Jong Hak
    • Membrane Journal
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    • v.29 no.4
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    • pp.223-230
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    • 2019
  • In this paper, we develop a polymeric blend membrane based on $CO_2$-philic poly(2-[3-(2H-benzotriazol-2-yl)-4-hydroxyphenyl] ethyl methacrylate)-poly(oxyethylene methacrylate) (PBEM-POEM) comb copolymer, which was synthesized by facile free radical polymerization. The PBEM-POEM (PBE) comb copolymer was blended with a commercial oligomer, low-molecular-weight poly(ethylene glycol) (PEG, $M_w=200gmol^{-1}$) with various ratios to prepare $CO_2/N_2$ separation membranes. From the result of $CO_2/N_2$ separation test of the PBE/PEG blend membranes with the various PEG contents, we could conclude that with increasing PEG content, the $CO_2/N_2$ selectivity significantly increased while the CO2 permeability decreased showing trade-off relationship. However, when comparing the performance of the PBE/PEG (9 : 1) with the PBE/PEG (7 : 3) membrane, the $CO_2$ permeance decreased by only 8.3%, while the $N_2$ permeance decreased by 69.1%. Therefore, the $CO_2/N_2$ selectivity dramatically increased from 33.8 to 100.3. This could be because the POEM chains, which account for 80% of the PBE copolymer, favorably interact with PEG and lead to a more compact chain structure, which was confirmed by FT-IR, XRD and SEM analysis. The PBE/PEG (7 : 3) blend membrane had the most optimal gas separation performance, showing a $CO_2$ permeance of 170.5 GPU and $CO_2/N_2$ selectivity of 100.3.

Expansion of the Value and Prospect of the Human Rights Documentary Heritage : Focusing on the 5·18 archives (인권기록유산 가치와 지평의 확산 5·18민주화운동기록물을 중심으로)

  • Lee, Jung Yeon
    • The Korean Journal of Archival Studies
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    • no.45
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    • pp.121-153
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    • 2015
  • Struggles to gain acknowledgement of identity have a characteristic of movement to recover human dignity. Participants in this movement come to confirm themselves as the subject of rights and communicate one another, free from oppression. Being guaranteed the opportunity to participate in the public opinion formation process is an indispensable element of human rights. In 1980, though it was short and incomplete, Gwangju experienced communal autonomy under the condition that state power was temporarily stopped. The contents and memories of the Gwangju Democratization Movement that intended to protect autonomy of civil society, resisting pillage of state power, remain intact in the 1980 Archives for the May 18th. The 5.18 archives were registered in UNESCO's Memory of the World in 2011, with its value of human rights and protection of democracy being acknowledged. The 5.18 archives have memories of resistance and struggles for justice, and sacrifices and pains of citizens under oppressive political authority in Gwangju, 1980. Thus, these archives are related to the historical struggles for democracy, and suggest a lesson on the transition process towards democracy to us. Preservation and utilization of the documentary heritage constantly lead the memories of historical events to the present, and enable exchanges of experiences and ideas between the present and the future. This study, through the process of UNESCO's Memory of the World registration and post-registration process, beyond the value of archives, tries to examine how historical events are led to the present, through the archives and to discuss the other values of archives.

An Exploration of IT Convergence Methods for School Forests Education (초, 중등 학교 숲 활용 교육을 위한 IT 융합 방안 탐색)

  • Kim, Sung-Ae
    • Journal of Convergence for Information Technology
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    • v.9 no.6
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    • pp.112-120
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    • 2019
  • The purpose of this study is to explore educational methods for elementary, middle and high schools using school forests via IT convergence. To this aim, we reviewed the previous literature on education using school forests to identify the problems with the existing education using school forests, and conducted interviews with experts to analyze the demands. we proposed an educational method that can utilize the school forests via IT convergence, and explored its validity through content reviews conducted by experts. The findings of this study are as follows. First, we proposed the IT convergence instruction focused on hands-on activities on top of the existing educational contents. Second, we proposed IT convergence instruction that incorporates diverse materials, physical computing tools, and programming tools. Third, we presented methods for utilizing such IT convergence instruction in connection with various elements of the 2015 Revised Curriculum as well as with various other activities such as middle school free semester activities and after-school activities. The school forest is a crucial learning space for the areas related to agriculture and biotechnology. Thus, we anticipate that the IT convergence instruction proposed in this study will lead to the re-discovery and re-evaluation of a value of school forests as an educational space that contributes to fulfilling the objective of the 2015 Revised Curriculum to nurture creative convergent talent.

A Study on the Development of 3D Virtual Reality Campus Tour System for the Adaptation of University Life to Freshmen in Non-face-to-face Situation - Autonomous Operation of Campus Surrounding Environment and University Information Guide Screen Design Using Visual Focus Movement - (비대면 상황에서 신입생 대학생활적응을 위한 3차원 가상현실 캠퍼스 투어시스템 개발연구 - 시야초점의 움직임을 활용한 캠퍼스주변 환경의 자유로운 이동과 대학정보안내화면 GUI설계 -)

  • Lim, Jang-Hoon
    • Journal of Information Technology Applications and Management
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    • v.28 no.3
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    • pp.59-75
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    • 2021
  • This study aims to establish a foundation for autonomous driving on campus and communication of abundant university information in the HCI environment in a VR environment where college freshmen can freely travel around campus facilities. The purpose of this study is to develop a three-dimensional VR-style campus tour system to establish a media environment to provide abundant university information guidance services to freshmen in non-face-to-face situations. This study designed a three-dimensional virtual reality campus tour system to solve the problem of discontinuity in which VR360 filming space does not lead to space like reality, and to solve many problems of expertise in VR technology by constructing an integrated production environment of tour system. We aim to solve the problem of inefficiency, which requires a large amount of momentum in virtual space, by constructing a GUI that utilizes the motion of the field of view focus. The campus environment was designed as a three-dimensional virtual reality using a three-dimensional graphic design. In non-face-to-face situations, college freshmen freely transformed the HMD VR device, smartphone, FPS operation mode of the gyroscope sensor. The design elements of the three-dimensional virtual reality campus tour system were classified as ①Visualization of factual experiences, ②Continuity of space movement, ③Operation, automatic operation mode, ④Natural landscape animation, ⑤Animation according to wind direction, ⑥Actual space movement mode, ⑦Informatization of spatial understanding, ⑧GUI by experience environment, ⑨Text GUI by building, ⑩VR360, 3D360 Studio Environment, ⑪Three-dimensional virtual space coupling block module, ⑫3D360-3D Virtual Space Transmedia Zone, ⑬Transformable GUI(VR Device Dual Viewer-Gyro Sensor Full Viewer-FPS Operation Viewer) and an integrated production environment was established with each element. It is launched online (http://vautu.com/u1) by constructing a GUI for free driving mode and college information screens to adapt to college life for freshmen, and designing an environment that can be used simultaneously by current media such as PCs, Android, and iPads. Therefore, it conducted user research, held a development presentation, a forum on excellence in university innovation support projects, and applied it as a system on the website of a particular university. College freshmen will be able to experience university information directly from the web and app to the virtual reality campus environment.

A Study on the Structural Stability and Effectiveness of Rope Cutter for Ship's Propeller (선박추진기용 로프절단장치의 구조 안정성 및 효용성에 관한 연구)

  • Kim, Jun-Soo;Seul, Youngyoon;Lee, Du-Yong;Park, Kitae;Kim, Tae Hun;Choi, Jae-Hyuk;Lee, Won-Ju
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.27 no.4
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    • pp.550-556
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    • 2021
  • The scissor-type rope cutter is the most widely used amongst all kinds of commercially available rope cutters in Korea. In this study, we performed finite element analysis on the scissor-type rope cutter. We determined the structure of the cutter that would ensure its stable operation in various situations involving rope entanglement, and verified its effectiveness by testing it in the lab and in an actual ship. These investigations revealed that when the propeller shaft was not rotated by rope entanglement, the constant torque generated by the engine resulted in the torsion of the rope cutter and maximum deformation in the lower blade, which was not restricted by finite element analysis. With increasing blade thickness, the maximum values of deformation and equivalent stress decreased, resulting in a rise in the safety factor. At the constant blade thickness, the effect of the torque variations on the maximum equivalent stress and the maximum deformation is independent of the position of the external force of the rope cutter and decreases in direct proportion. The results of this study confirmed that the rope-cutter structure determined by analysis could lead to a hassle-free removal of ropes and fishing nets under all conditions and environments.

A Study on the Effect of Returned Farming Infrastructure and Returned Farming Characteristics on the Satisfaction after Returning Farming (귀농 인프라와 귀농자의 특성이 귀농 후 만족에 미치는 영향에 관한 연구)

  • Lee, Ji-Hun;Kim, Myung-Soo
    • Journal of Korea Entertainment Industry Association
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    • v.14 no.3
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    • pp.139-148
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    • 2020
  • Through this study, the policy proposals were intended to be presented to the head of the farming policy. Therefore, the meaning of this study is as follows. First, rather than judging the returning farmer on his own, he should provide sufficient information to consult with his family and increase access to agriculture. Second, by opening up SNS and YouTube to returning farmers, they should instill confidence in rural areas by providing them with information about the joy of rural life and the success of farming so that they can easily access information about rural life through villages, youth associations and women's associations. Efforts should be made to create vibrant rural areas by providing infrastructure around farmland, providing various amenities for settling young people and forming a family farmers' association. Third, the head of the return farming policy should come up with customized support policies for the return farming (e.g., one-year farm support, free farm support, institutional sales guarantee, tourism in advanced countries, modernization of farmland facilities). Public relations strategies should also be strengthened so that such policies can lead to agriculture. Finally, the government should provide subsidized economic activities (e.g. Airbnb, donation of expertise and work-related personnel before returning home, rural experience, etc.).

A Block-based Uniformly Distributed Random Node Arrangement Method Enabling to Wirelessly Link Neighbor Nodes within the Communication Range in Free 3-Dimensional Network Spaces (장애물이 없는 3차원 네트워크 공간에서 통신 범위 내에 무선 링크가 가능한 블록 기반의 균등 분포 무작위 노드 배치 방법)

  • Lim, DongHyun;Kim, Changhwa
    • Journal of Korea Multimedia Society
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    • v.25 no.10
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    • pp.1404-1415
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    • 2022
  • The 2-dimensional arrangement method of nodes has been used in most of RF (Radio Frequency) based communication network simulations. However, this method is not useful for the an none-obstacle 3-dimensional space networks in which the propagation delay speed in communication is very slow and, moreover, the values of performance factors such as the communication speed and the error rate change on the depth of node. Such a typical example is an underwater communication network. The 2-dimensional arrangement method is also not useful for the RF based network like some WSNs (Wireless Sensor Networks), IBSs (Intelligent Building Systems), or smart homes, in which the distance between nodes is short or some of nodes can be arranged overlapping with their different heights in similar planar location. In such cases, the 2-dimensional network simulation results are highly inaccurate and unbelievable so that they lead to user's erroneous predictions and judgments. For these reasons, in this paper, we propose a method to place uniformly and randomly communication nodes in 3-dimensional network space, making the wireless link with neighbor node possible. In this method, based on the communication rage of the node, blocks are generated to construct the 3-dimensional network and a node per one block is generated and placed within a block area. In this paper, we also introduce an algorithm based on this method and we show the performance results and evaluations on the average time in a node generation and arrangement, and the arrangement time and scatter-plotted visualization time of all nodes according to the number of them. In addition, comparison with previous studies is conducted. As a result of evaluating the performance of the algorithm, it was found that the processing time of the algorithm was proportional to the number of nodes to be created, and the average generation time of one node was between 0.238 and 0.28 us. ultimately, There is no problem even if a simulation network with a large number of nodes is created, so it can be sufficiently introduced at the time of simulation.

Explanable Artificial Intelligence Study based on Blockchain Using Point Cloud (포인트 클라우드를 이용한 블록체인 기반 설명 가능한 인공지능 연구)

  • Hong, Sunghyuck
    • Journal of Convergence for Information Technology
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    • v.11 no.8
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    • pp.36-41
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    • 2021
  • Although the technology for prediction or analysis using artificial intelligence is constantly developing, a black-box problem does not interpret the decision-making process. Therefore, the decision process of the AI model can not be interpreted from the user's point of view, which leads to unreliable results. We investigated the problems of artificial intelligence and explainable artificial intelligence using Blockchain to solve them. Data from the decision-making process of artificial intelligence models, which can be explained with Blockchain, are stored in Blockchain with time stamps, among other things. Blockchain provides anti-counterfeiting of the stored data, and due to the nature of Blockchain, it allows free access to data such as decision processes stored in blocks. The difficulty of creating explainable artificial intelligence models is a large part of the complexity of existing models. Therefore, using the point cloud to increase the efficiency of 3D data processing and the processing procedures will shorten the decision-making process to facilitate an explainable artificial intelligence model. To solve the oracle problem, which may lead to data falsification or corruption when storing data in the Blockchain, a blockchain artificial intelligence problem was solved by proposing a blockchain-based explainable artificial intelligence model that passes through an intermediary in the storage process.