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Fine Dust Adsorption of Cement Matrix Using Sepiolite (세피올라이트를 활용한 시멘트 경화체의 미세먼지 흡착 특성 )

  • Jeon, Eun-Yeong;Lee, Sang-Soo
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2023.11a
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    • pp.71-72
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    • 2023
  • As industrialization and urbanization accelerate, environmental issues have moved from local concerns to global issues. Among them, air pollution is the most important issue. Modern people spend more than 88% of their day indoors, but the concentration of fine dust and pollutants flowing indoors is increasing. The indoor environment has its own complexity, and various substances used indoors, such as building materials, furniture, electronics, and cleaning agents, emit chemical substances and cause various diseases. Therefore, when selecting building materials and interior finishing materials, the pollutant emission and adsorption capacity must be greatly considered. These considerations will ensure the construction of a sustainable future environment and a healthy life within that environment. Therefore, in order to reduce the generation of indoor air pollutants, this study aims to examine the fine dust adsorption properties of cement hardening materials using sepiolite, which has a porous structure and high absorption power among clay minerals. As a result of the experiment, it was found that the concentration of fine dust decreased as the addition rate of sepiolite increased. It is believed that the fine dust concentration was reduced due to the high porosity due to the microfibrous structure and large specific surface area of sepiolite, which has a porous structure among clay minerals. It is believed that these experimental results can be used as basic research for future use of sepiolite as a construction material.

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A reduced order model for fission gas diffusion in columnar grains

  • D. Pizzocri;M. Di Gennaro;T. Barani;F.A.B. Silva;G. Zullo;S. Lorenzi;A. Cammi
    • Nuclear Engineering and Technology
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    • v.55 no.11
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    • pp.3983-3995
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    • 2023
  • In fast reactors, restructuring of the fuel micro-structure driven by high temperature and high temperature gradient can cause the formation of columnar grains. The non-spheroidal shape and the non-uniform temperature field in such columnar grains implies that standard models for fission gas diffusion can not be applied. To tackle this issue, we present a reduced order model for the fission gas diffusion process which is applicable in different geometries and with non-uniform temperature fields, maintaining a computational requirement in line with its application in fuel performance codes. This innovative application of reduced order models as meso-scale tools within fuel performance codes represents a first-of-a-kind achievement that can be extended beyond fission gas behaviour.

A Study on Improving License Plate Recognition Performance Using Super-Resolution Techniques

  • Kyeongseok JANG;Kwangchul SON
    • Korean Journal of Artificial Intelligence
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    • v.12 no.3
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    • pp.1-7
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    • 2024
  • In this paper, we propose an innovative super-resolution technique to address the issue of reduced accuracy in license plate recognition caused by low-resolution images. Conventional vehicle license plate recognition systems have relied on images obtained from fixed surveillance cameras for traffic detection to perform vehicle detection, tracking, and license plate recognition. However, during this process, image quality degradation occurred due to the physical distance between the camera and the vehicle, vehicle movement, and external environmental factors such as weather and lighting conditions. In particular, the acquisition of low-resolution images due to camera performance limitations has been a major cause of significantly reduced accuracy in license plate recognition. To solve this problem, we propose a Single Image Super-Resolution (SISR) model with a parallel structure that combines Multi-Scale and Attention Mechanism. This model is capable of effectively extracting features at various scales and focusing on important areas. Specifically, it generates feature maps of various sizes through a multi-branch structure and emphasizes the key features of license plates using an Attention Mechanism. Experimental results show that the proposed model demonstrates significantly improved recognition accuracy compared to existing vehicle license plate super-resolution methods using Bicubic Interpolation.

Research on Development of Magnetic Silicon Mold to Improve Free-form Concrete Panel Precision by Lateral Pressure

  • Jongyoung YOUN;Kyeongtae JEONG;Minje JO;Jihye KIM;Donghoon LEE
    • International conference on construction engineering and project management
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    • 2024.07a
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    • pp.186-192
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    • 2024
  • Free-form buildings are composed of different curved surfaces and panels with varying curvatures used for the exterior. Because free-form curved surfaces differ from those of conventional buildings, they serve as landmarks worldwide and generate economic and social profits. However, molds used to realize the curved surfaces of free-form buildings are typically single-use, resulting in construction waste and posing limitations such as environmental pollution and increased construction costs. To address this issue, current research is focused on developing reusable forms that precisely implement free-form curved surfaces. Among these approaches, the Free-form Concrete Panel (FCP) employs reusable silicone material as a mold. The silicone mold consists of a lower part and a side part, with both parts fixed together by friction due to the same material. However, during the concrete pouring process into the silicone mold, lateral pressure can cause shifting, reducing the precision of the FCP and resulting in defective panels. To address this challenge, this study introduces the use of iron powder in the lower part and magnets on the sides to secure the form using magnetic force.

A Study on the News Frames Represented in Dismissal Procedure of the Director General of the PSB (공영방송 사장의 해임 뉴스보도에 나타난 프레임 분석연구)

  • Choi, Sun-Wook;Yu, Hong-Sik
    • Korean journal of communication and information
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    • v.52
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    • pp.69-89
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    • 2010
  • We investigated the frames represented in the news media coverage in Korean daily newspapers during dismissal procedure of the director-general of the public service broadcaster, KBS. We analyzed 470 newspaper stories in the period surrounding the dismissal. The use of news frames in newspapers depended on the disposition of outlets, conservative or progressive. Conservative newspapers, ChoSun and DongA, described the dismissal of the director -general with a generally favorable or supportive view, but progressive outlets, Hankyoreh and KyeongHyang, reported more and non-favorable for the issue. Our results showed that conservative newspapers more often used episodic and cause for dismissal frame in the presentation of news, whereas progressive more often used thematic and media independence frames. Main frames commonly used in the news are the cause for dismissal, conflict, media independence, and regime maintenance, respectively, which are formed by 9 minor news frames. Conservative newspapers concentered on the cause attribution; management responsibility, conflicts, and dismissal procedures, but progressive focused on media independence and dismissal procedures. All newspapers selectively quoted groups, institutions and actors to enhance their messages and frames. Finally, there was significant difference between stories in each newspapers and the court's ruling for the dismissal.

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A Study on the Cause of Job Stress of Urban Railroad Drivers: Focused on Railroad Companies of Daejeon, Daegu, Incheon and Seoul Metro 9 (도시철도 기관사의 직무스트레스 원인 특성에 관한 연구: 대전, 대구, 인천, 서울9호선 운영회사를 대상으로)

  • Park, Taesoo;Lee, Jinsun;Kim, Hongki
    • Journal of the Korean Society for Railway
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    • v.16 no.4
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    • pp.340-347
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    • 2013
  • This paper studied the causes of job stress of driving crews working in Metropolitan Transit Authorities in Daejeon, Daegu, Seoul Metro Line 9, and Incheon, analyzing psychological, physical, and environmental factors, along withdriving crews' assignments. Regarding driving crews' assignments, it was found that driving crews had strong senses of obligation for their job, and hence their aptitude for their job was in accordance, and also it was found that most driving crews worked devotedly with a desirable occupational view and pride. However, psychological and physical factors that contributed to stress were identified: lack of sleep, high task burden, physical fatigue, and boring daily life. Furthermore, the driving crews' irregular working conditions and irregular meal time and burden related to on-time transit service with prolonged immobilization raised their stress levels. In terms of external environmental factors, it was found that driving crews' anxiety due to possible accidents caused a roughly four-fold increase in stress levels compared to other factors. Furthermore, personnel system and salary issue were also found to be closely related to the driving crews' job stress.

Systematic Review of the Cause of Drug-Induced Liver Injuries in Korean Literature (약인성 간손상의 원인물질에 관한 국내연구의 체계적 고찰)

  • Yun, Young-Ju;Shin, Byung-Cheul;Lee, Myeong-Soo;Cho, Sung-Il;Park, Jae-Hyeon;Lee, Hye-Jung
    • The Journal of Korean Medicine
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    • v.30 no.2
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    • pp.30-45
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    • 2009
  • Background: The safety of herbal products is an important issue in Korea. It is more complicated because of the concomitant use of conventional western drugs and herbal medicine, including prescribed medicine, folk herbs and food supplements. Although both western and traditional Korean medical doctors have studied on the safety of HMP, their results did not show relevant or consistent conclusions because of the poor quality of studies, including bias. Objectives: The aim of this study was to review the studies in Korea related to drug induced liver injury (DILI) systematically. We tried to estimate the proportion of causative materials of DILI and evaluate the clinical difference of DILIs from different materials. Methods: Systematic searches were performed on MedRIC and MEDLIS in Korea. The extraction of data as well as selective screening of the studies was carried out independently by two of the authors. There were no restrictions on the types of publication, including grey literature. Results: Twenty-one articles were included. Of them only 7 adapted prospective design and only 6 were published in peer-reviewed journals. The proportion of conventional drugs associated with hepatotoxic injuries in all DILI ranged from 15.8% to 83.3% and that of herbal medicine was from 28.9% to 44.7%. However, the criteria for herbal medicine were not clearly defined and concomitant medications were not fully investigated in most studies. There were limited objective data in the clinical differences of liver injuries from different materials and their results were conflicting. Conclusions: The causality assessments regarding DILI of herbal medicine were not performed properly and causative materials were misclassified in most of the studies published in Korea. These make the safety issue still ambiguous because of the limitations and lack of objectivity of the studies. More rigorous studies are required for clearly addressing these conflicting issues with cooperative investigation between traditional Korean and western medicine.

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An Experiential Analysis on Scolding behavior of Elementary School Teachers (꾸중에 대한 초등교사의 체험분석)

  • Kim, Jong-Sook
    • The Korean Journal of Elementary Counseling
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    • v.6 no.1
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    • pp.95-116
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    • 2007
  • This thesis is aimed to understand when and how elementary teachers scold their students and to explore any common psychological factors shown in the process. In order to produce the meaningful results of the research, applied is experience-based analysing method which expectedly leads to discovering psychological cause and effect occurring when school teachers scold students. 11 teachers of elementary school, including me the author, have joined as co-researchers to solve the next two issues and I made guidelines for the analysis. Given that co-researchers are locally scattered, they were grouped into three and in the mean time, analysis on scolding during 4 meeting sessions were made. The results of research problems are as follows. First issue: What common psychological factors exist in when and how teachers scold students? Common factors in 'when' part include three cases: teachers discovering the factors hindering student's desirable growth, noticing the class rules and peaceful communities are broken, or experiencing humiliating remarks and annoying behaviors and In "how' part, on the other hand, teachers speak up in a stronger voice or raise their tone to point out student's wrongdoing and give students a stoic and fierce look. Second issue: What psychological development takes place in scolding? Teachers who participated in this scolding experiment have experienced' feeling responsible and upset'. Feeling responsible is highly likely to be interpreted to result from the idea that teachers supposedly support students to grow into well-functional person in society. Meanwhile, feeling upset or even humiliated is caused by the frustration when they find their authority and dignity Ignored and damaged. The phases teachers go through during the scolding are: recognizing scold-inviting situation-> interpreting clues deserving enough to scold-> being aroused into the feelings-> deciding how to respond-> executing decision-> dealing with emotion. This thesis has distinctive qualities from existing ones in that the research focuses on agonies and conflicts faced with school teachers in class. On top of that, it is noted that this thesis meaningfully enables to realize teachers' psychological mechanism activated from scolding and to provide teachers with opportunities to see themselves more proper perspectives. However, there still remains some reservation since I had rather short period of time to collect data and we, co-researchers, had meeting sessions. To compensate for the possible shortcomings shown in this thesis, further research is expected to be followed to perform a practical analysis.

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Applying Novelty Detection for Checking the Integrity of BIM Entity to IFC Class Associations (Novelty detection을 이용한 BIM객체와 IFC 클래스 간 매핑의 무결성 검토에 관한 연구)

  • Koo, Bonsang;Shin, Byungjin
    • Korean Journal of Construction Engineering and Management
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    • v.18 no.6
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    • pp.78-88
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    • 2017
  • With the growing use of BIM in the AEC industry, various new applications are being developed to meet these specific needs. Such developments have increased the importance of Industry Foundation Classes, which is the international standard for sharing BIM data and thus ensuring interoperability. However, mapping individual BIM objects to IFC entities is still a manual task, and is a main cause for errors or omissions during data transfers. This research focused on addressing this issue by applying novelty detection, which is a technique for detecting anomalies in data. By training the algorithm to learn the geometry of IFC entities, misclassifications (i.e., outliers) can be detected automatically. Two IFC classes (ifcWall, ifcDoor) were trained using objects from three BIM models. The results showed that the algorithm was able to correctly identify 141 of 160 outliers. Novelty detection is thus suggested as a competent solution to resolve the mapping issue, mainly due to its ability to create multiple inlier boundaries and ex ante training of element geometry.

Nation-wide Interoperable transportation card X-CASH System and Settlement interface Development (전국호환 교통카드 X-CASH 시스템과 정산인터페이스 개발)

  • Lee, Ki-Han;Kim, Hye-Hyeon;Kim, Tae-Hee;Maeng, Jae-Hwan;Park, Ha-Na
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.9 no.5
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    • pp.14-24
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    • 2010
  • Although the existing X-CASH card system observes the KS standard for a transportation card system, there has been an issue for interoperability between X-CASH and other public transportation system due to the partially undefined part in the standard. This issue is followed by the inconvenience of the existing X-CASH users. If the existing X-CASH card user wants to get any other public transportations which are not interoperated with X-CASH, the user would have to buy other cards. Consequently, some users have to bring more than one card with them. In addition, it is almost impossible that the existing X-CASH system operator makes the X-CASH card available for the infrastructure built by other cards operators because their technologies are too much different. The X-CASH operator must construct its own infrastructure on the same route and it would cause an unnecessary loss of expense and labor. To solve these problems, We modified the existing X-CASH system and developed the Nation-wide Interoerable X-CASH system which lets both the existing X-CASH card and Nation-wide Interoperable X-CASH card work. This developed X-CASH system consists of the purchase SAM, the purchase terminal and the settlement. And The conformity test for it was successfully authorized. Also we, KORAIL NETWORKS, have done the test-bed on this Nation-wide interoperable X-CASH system in Gwangju for six months with Telecommunications & Clearings, the HiPlusCard Corporation. This test confirmed that the Nation-wide Interoperable X-CASH system would practically work well.