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Threshold Condition for Exclusion of Riprap into Bypass Pipe (저층수 배출관에 유입된 사석의 배제 한계조건)

  • Jeong, Seokil;Lee, Seung Oh
    • Journal of Korean Society of Disaster and Security
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    • v.12 no.1
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    • pp.57-66
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    • 2019
  • One of the most serious problems with concrete small dams or barriers installed in small/median rivers is the deposit of sediments, especially, in Korea. An effective way to discharge such sediments to downstream is to construct a bypass pipe under the river bed. However, efficiency may become lowered if ripraps are entered into the bypass pipe. Therefore, in this study, we derived the threshold condition for the exclusion of ripraps from the bypass pipe using 3D numerical analysis. Upstream flow of the small dam was assumed to be stationary, and the energy concept was applied to the control volume containing the bypass pipe and its periphery. As a result, when the ratio of the water level difference between upstream and downstream to the diameter of the riprap was approximately equal to 1.2, the threshold condition for exclusion of the stones or riprap from the bypass pipe was affirmatively determined. If the characteristics of the adsorptive sediment adversely affecting the river environment in the future would be taken into account, results from this study are expected to put to practical use in the management of concrete small dam with bypass pipe system.

Comparative Analysis on the Sound Characteristics of Riffles and Pools (여울과 소의 소리특성 비교 분석)

  • Kang, Su-Jin;Kang, Joon-Gu;Kim, Jong-Tae
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.12
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    • pp.878-886
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    • 2018
  • This study quantified the sounds of riffles and pools in natural rivers and conducted a comparative analysis of the frequency and sound pressure per flow velocity. The surveyed area was Namdaecheon basin in Yangyang-gun, Gangwon-do and the sounds of a total of 23 sites were analyzed. A hydro microphone was used to measure the sound and analyze the data using an acoustic analysis program. The location was also selected at places with minimal ambient noise and the measurement points were the depth of riffles and pools. The results revealed an average difference of 0.515 m/s for flow velocity at 8 riffles and 15 pools. The difference in sound pressure occurred due to the flow velocity. In the case of sound pressure, it was measured at an average of 176.8 dB for riffles and 168.2 dB for pools, demonstrating a difference of approximately 8.6 dB. Furthermore, in the case of maximum sound pressure, riffles showed a constant range between 200 Hz and 250 Hz, while the pools exhibited maximum sound pressure at various frequencies from 200 Hz to 1,000 Hz. This revealed the ecological stream reproduction, development of preferred sound sources for aquatic life, and design of structures.

Classification of Forest Vertical Structure Using Machine Learning Analysis (머신러닝 기법을 이용한 산림의 층위구조 분류)

  • Kwon, Soo-Kyung;Lee, Yong-Suk;Kim, Dae-Seong;Jung, Hyung-Sup
    • Korean Journal of Remote Sensing
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    • v.35 no.2
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    • pp.229-239
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    • 2019
  • All vegetation colonies have layered structure. This layer is called 'forest vertical structure.' Nowadays it is considered as an important indicator to estimate forest's vital condition, diversity and environmental effect of forest. So forest vertical structure should be surveyed. However, vertical structure is a kind of inner structure, so forest surveys are generally conducted through field surveys, a traditional forest inventory method which costs plenty of time and budget. Therefore, in this study, we propose a useful method to classify the vertical structure of forests using remote sensing aerial photographs and machine learning capable of mass data mining in order to reduce time and budget for forest vertical structure investigation. We classified it as SVM (Support Vector Machine) using RGB airborne photos and LiDAR (Light Detection and Ranging) DSM (Digital Surface Model) DTM (Digital Terrain Model). Accuracy based on pixel count is 66.22% when compared to field survey results. It is concluded that classification accuracy of layer classification is relatively high for single-layer and multi-layer classification, but it was concluded that it is difficult in multi-layer classification. The results of this study are expected to further develop the field of machine learning research on vegetation structure by collecting various vegetation data and image data in the future.

Relationship between the Ancient Silk Road and High-technology Machine in Producing Kyung-Geum (고대 실크로드와 고조선 경금 제직기의 연관성 고찰)

  • Kim, Ji-Su;Na, Young-Joo
    • Science of Emotion and Sensibility
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    • v.23 no.4
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    • pp.117-142
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    • 2020
  • This study aims to look for the main transport road of the ancient Silk Road and to add to the hidden history of silk, where little is known about the weaving technology of the beautiful silk of GoJoseon. The research was through the analysis of relics of empirical data and analyzed the secondary data collected from books, papers, and photos of artifacts. The research questions are as follows: First, investigates the environment of silk production for GoJoseon KyungGeum and the correlation between ancient Silk Road and the East region. Second, examines the advanced weaving technology of KyungGeum in GoJoseon. The findings of the study are as follows: It is possible to infer the production period of silk in GoJoseon through jade silkworms from the Hongsan Dong-Yi culture of 4500 BC. KyungGeum pieces were excavated in Louran, Astana and Niya of the Xinjiang Autonomous Region and Noin-Ula of Mongolia, and the oldest KyungGeum was found in JoYang, one of the capitals of GoJoseon near Balhae Bay. KyungGeum was invented in the 11th century BCE here. It became the brocade and damask of the West, which were delivered through steppe road before the 5~6th century BCE. The production of KyungGeum was possible through the advanced loom which is GoJoseon's horizontal square 'Jewharu' loom combined with a high level of weaving skill. This can't be made through the slant loom of China nor vertical loom of the West Asia. Based on these results, it is suggested to continue the research on the history of ancient silkroad.

A Knowledge Graph on Japanese "Comfort Women": Interlinking Fragmented Digital Archival Resources (일본군 '위안부' 지식그래프: 파편화된 디지털 기록의 연결)

  • Park, Haram;Kim, Haklae
    • Journal of Korean Society of Archives and Records Management
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    • v.21 no.3
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    • pp.61-78
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    • 2021
  • Records on Japanese "Comfort Women" have been individually managed by private sectors or institutions, and some are provided as digital archives on the Internet. However, records of digital archives differ in the composition and representation of metadata by individual institutions. Meanwhile, there is a lack of a consistent structure to describe the relationships between and among these records, leading to their fragmentation and disconnectedness. This paper proposes a knowledge model for interlinking the digital archival resources and builds a knowledge graph by integrating the records from distributed digital archives. It derives common elements by analyzing metadata from the diverse digital archives and expresses them in standard vocabularies to semantically describe multiple entities and relationships of the digital archival resources. In particular, the study includes the refinement of collected data to search and thread dispersed records and the enrichment of external data to provide significant contextual information of records. An evaluation of the knowledge graph is performed via a query measuring the (dis)connectivity between the distributed records. As a result, the knowledge graph is capable of interlinking and retrieving fragmented records, providing substantial contextual information on the records with external data enrichment, and searching accurately to match the user's intentions through semantic-based queries.

UX Design Proposal for Educational Software Service Middle-aged and Elderly (중·고령층 키오스크 교육용 소프트웨어 서비스를 위한 UX 디자인)

  • Yoon, Yea-Jin;Ha, Kwang-Soo
    • The Journal of the Korea Contents Association
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    • v.21 no.10
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    • pp.227-239
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    • 2021
  • The transition into a digital society has been accelerated in many aspects of our everyday social activities, and thereby, the unmanned order and payment system via kiosk has already has been seen commonly throughout the social community. Yet, the majority of the mid-to-elderly population have been experiencing difficulties utilizing this newly emerged unmanned system, resulting in the emergence of digital alienation among those age groups. In regard to this phenomenon, this study is intended to explore ways to improve the digital divide concerning the issues related to the unmanned order payment kiosks. In this process, the study involved close examination of various research perspectives on improving the digital divide and proceeded with the focus on both empirical and literature research on providing education on kiosk utilization. In addition, the study identified the limitations to the current kiosk education and proposed improved kiosk-education software UX that may help curtail the limitations. Through this, one was able to identify areas in which the efficacy of the education applied in kiosk usage and derived new measures that could improve the system. One anticipates having the results of this study put to use as research materials on educational service development to expand the opportunities of kiosk education for those mid-to-elderly age groups who experience a day-to-day digital alienation.

A Case Study of Spatial CAD Education in Blended Learning Environment (혼합형 학습(Blended Learning) 환경에서의 공간디자인 CAD 수업 사례연구)

  • Hwang, Ji Hyoun;Lim, Haewon
    • The Journal of the Korea Contents Association
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    • v.21 no.10
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    • pp.115-126
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    • 2021
  • The purpose of this study is to closely analyze the case of blended-learning in order to provide a diverse and flexible learning environment while maintaining the nature of face-to-face classes, and to identify the learning environment that supports blended-learning in each class step and the educational experience of students. The experience and satisfaction of blended learning were investigated in various ways: course evaluation, LMS activity evaluation, and questionnaire before and after the class. As a result, the blended-learning is better than the traditional face-to-face classes, in providing real-time feedback, opportunities for various interactions, and textual conversations, anytime and anywhere. In addition, as a result of the preliminary survey, as a measure to solve the opinion that concentration was reduced due to problems such as networks and felt uncomfortable in the communication part, the theory and lectures of the design practice class were conducted non-face-to-face. The individual Q&A and feedback were conducted face-to-face and non-face-to-face. As a result of the follow-up survey, it was found that concentration and efficiency could be improved. This opens up possibilities for active use of the online environment in design practice classes.

Development of an Inverted Y-Shaped Strip for the Detection of Organophosphorus and Carbamate Residual Pesticides (유기인계 및 카바메이트계 농약 신속 검출을 위한 역 Y자 스트립의 개발)

  • Lee, Jeong-Eun;Kim, Sol-A;Park, Hyun-Jin;Mun, Hyoyoung;Shim, Won-Bo
    • Journal of Food Hygiene and Safety
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    • v.36 no.1
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    • pp.1-8
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    • 2021
  • The inverted Y-shaped strip detection method based on acetylcholinesterase (AChE) was developed for the rapid detection of organophosphorus and carbamate pesticides. The inactivation of AChE by organophosphorus and carbamate pesticides has been well known. The AChE catalyzes acetylthiocholine into thiocholine having (-) and (+) charges, and the (+) charge results in aggregation of gold nanoparticle (GNP). Malaoxon and carbofuran were used as standard organophosphorus and carbamate for the development of the inverted Y-shaped strip, respectively. In order to optimize the method, various angles of the Y-shaped strip, different types of nitrocellulose membrane, and concentration of AChE were tested as key parameters. The detection limit of the method was 10 ng/mL for both malaoxon and carbofuran pesticides. No cross-reaction was observed to other pesticides such as atrazine, cyanazine, simazine, bifenthrin, boscalid, metalaxyl, and chlorobenzilate. Recoveries from lettuce spiked when known concentrations of malaoxon and carbofuran were found ranging from 96.4 to 100.7% and 81 to 112.7%, respectively. This study suggests that the inverted Y-shaped strip method based on AChE may be a useful tool for the sensitive, specific, rapid detection of organophosphorus and carbamate pesticides in agricultural products.

The Preventive Effect of Bacillus polyfermenticus KJS-2 and Bacillus mojavensis KJS-3 on Triton WR-1339-induced Hyperlipidemia (Triton WR-1339로 유도된 고지혈증에 대한 Bacillus polyfermenticus KJS-2와 Bacillus mojavensis KJS-3의 예방효과)

  • Lee, Jin Young;Lee, Seung Jae;Kim, Hyung Hoi;Kang, Jae Seon
    • Journal of Life Science
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    • v.31 no.3
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    • pp.346-355
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    • 2021
  • The purpose of this study was to evaluate the possibility that administration of Bacillus polyfermenticus KJS-2 (BP2), Bacillus mojavensis KJS-3 (Moja3), and their mixtures could control serum lipid levels. We observed changes in the blood cell level, metabolic function evaluation, and blood lipid levels after two weeks of oral administration of these microbial strains to hyperlipidemia-induced rats. Measurements of major cell changes in the white blood cells (WBC) indicated no significant effects due to the administration of the microbial strains. Platelet (PLT) levels decreased by 18.4% in the Triton WR-1339-treated group (NCON) and recovered to the control (CON) group levels in the positive control (PCON) group and the microbial strain-administered groups (p<0.05). No functional changes were observed in red blood cells (RBC) by Triton WR-1339-induced hyperlipidemia. The blood AST, ALT, BUN, and creatinine levels did not indicated effects on liver and kidney function, and all rats administered the microbial mixture recovered. The blood lipid levels in the microbe-treated groups indicated reduced levels of triglyceride (TG) and total cholesterol (TC), and increased levels of serum HDL cholesterol. The HMG-CoA inhibition rate of 7-O-succinyl macrolactin A (SMA) produced by BP2 showed similar activity at a concentration of 1,000 times lower than that achieved with atorvastatin. The administration of the microbial strains to the Triton WR-1339-induced rat model of hyperlipidemia resulted in reduced weight gain without affecting the food and water intake. Thus, blood circulation can be improved by controlling serum lipid levels by the combined administration of the BP2 and Moja3 microbial strains.

A Study on the Ideology Education of Children during the Asian Pacific War (아시아태평양전쟁기 아동의 사상교육에 관한 연구)

  • Kwon, Hee-Ju;Sung, Yun-A
    • Journal of the Korea Convergence Society
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    • v.11 no.12
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    • pp.225-232
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    • 2020
  • In This paper examines how "Kamishibai" was used for ideological education of children during the war. "Kamishibai" was proposed by the Ministry of Education as a methodology to "cultivate children's right concentricity. In particular, , which was produced based on a true story, highlights the father's love sent to children by obtaining chocolate wrappers from comrades, and the children's envy for chocolate. Kazuo's interview, saying, "I will succeed my father," showed that he has a continuous personality that comes with another sacrifice. After the Sino-Japanese War, the war situation intensified, and in 1940, a new edict decided to enact the "Army Support Corps". This is a measure to select eligible youth applicants from 15 to 17 years of age, after training for 4 years, and then appoint them to aviation soldiers and sergeants. This is a legal maintenance that can be put into the battlefield at any time according to the trend of the war. Just as Kazuo, a real character in "Chocolate and Soldiers", also became a "boy flight soldier" after his father's death, flying airplanes to boys at the time was also a dream that Japan's great citizens should have. In the , it is suggested that "the father enshrined in Yasukuni" is a great person, and that "I" will also grow and become a "good citizen". In particular, the two brothers in the work show the value of eternal sacrifices in Yasukuni as a typical model of the "great people".