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Exploring the power of physics-informed neural networks for accurate and efficient solutions to 1D shallow water equations (물리 정보 신경망을 이용한 1차원 천수방정식의 해석)

  • Nguyen, Van Giang;Nguyen, Van Linh;Jung, Sungho;An, Hyunuk;Lee, Giha
    • Journal of Korea Water Resources Association
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    • v.56 no.12
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    • pp.939-953
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    • 2023
  • Shallow water equations (SWE) serve as fundamental equations governing the movement of the water. Traditional numerical approaches for solving these equations generally face various challenges, such as sensitivity to mesh generation, and numerical oscillation, or become more computationally unstable around shock and discontinuities regions. In this study, we present a novel approach that leverages the power of physics-informed neural networks (PINNs) to approximate the solution of the SWE. PINNs integrate physical law directly into the neural network architecture, enabling the accurate approximation of solutions to the SWE. We provide a comprehensive methodology for formulating the SWE within the PINNs framework, encompassing network architecture, training strategy, and data generation techniques. Through the results obtained from experiments, we found that PINNs could be an accurate output solution of SWE when its results were compared with the analytical method. In addition, PINNs also present better performance over the Artificial Neural Network. This study highlights the transformative potential of PINNs in revolutionizing water resources research, offering a new paradigm for accurate and efficient solutions to the SVE.

Time-series Change Analysis of Quarry using UAV and Aerial LiDAR (UAV와 LiDAR를 활용한 토석채취지의 시계열 변화 분석)

  • Dong-Hwan Park;Woo-Dam Sim
    • Journal of the Korean Association of Geographic Information Studies
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    • v.27 no.2
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    • pp.34-44
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    • 2024
  • Recently, due to abnormal climate caused by climate change, natural disasters such as floods, landslides, and soil outflows are rapidly increasing. In Korea, more than 63% of the land is vulnerable to slope disasters due to the geographical characteristics of mountainous areas, and in particular, Quarry mines soil and rocks, so there is a high risk of landslides not only inside the workplace but also outside.Accordingly, this study built a DEM using UAV and aviation LiDAR for monitoring the quarry, conducted a time series change analysis, and proposed an optimal DEM construction method for monitoring the soil collection site. For DEM construction, UAV and LiDAR-based Point Cloud were built, and the ground was extracted using three algorithms: Aggressive Classification (AC), Conservative Classification (CC), and Standard Classification (SC). UAV and LiDAR-based DEM constructed according to the algorithm evaluated accuracy through comparison with digital map-based DEM.

Analysis of Heat-generating Performance, Flexural Strength and Microstructure of Conductive Mortar Mixed with Micro Steel Fiber and MWCNT (마이크로 강섬유와 MWCNT를 혼입한 전도성 모르타르의 발열성능, 휨강도 및 미세구조 분석 )

  • Beom-gyun Choi;Gwang-hee Heo
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.28 no.3
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    • pp.47-58
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    • 2024
  • This study were conduced experimentally to analyze the heat-generating performance, flexural strength, and microstructure of conductive mortar mixed with micro steel fiber and multi-wall carbon nanotube (MWCNT). In the conductive mortar heat-generating performance and flexural strength tests, the mixing concentration of MWCNT was selected as 0.0wt%, 0.5wt%, and 1.0wt% relative to the weight of cement, and micro steel fibers were mixed at 2.0vol% relative to the volume. The performance experiments were conducted with various applied voltages (DC 10V, 30V, 60V) and different electrode spacings (40 mm, 120 mm) as parameters, and the flexural strength was measured at the curing age of 28 days and compared and analyzed with the normal mortar. Furthermore, the surface shape and microstructure of conductive mortar were analyzed using a field emission scanning electron microscope (FE-SEM). The results showed that the heat-generating performance improved as the mixing concentration of MWCNT and the applied voltage increased, and it further improved as the electrode spacing became narrower. However, even if the mixing concentration of MWCNT was added up to 1.0 wt%, the heat-generating performance was not significantly improved. As a result of the flexural strength test, the average flexural strength of all specimens except the PM specimen and the MWCNT mixed specimens was 4.5 MPa or more, showing high flexural strength due to the incorporation of micro steel fibers. Through FE-SEM image analysis, Through FE-SEM image analysis, it was confirmed that a conductive network was formed between micro steel fibers and MWCNT particles in the cement matrix.

A Study on the Density Analysis of Multi-objects Using Drone Imaging (드론 영상을 활용한 다중객체의 밀집도 분석 연구)

  • WonSeok Jang;HyunSu Kim;JinMan Park;MiSeon Han;SeongChae Baek;JeJin Park
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.23 no.2
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    • pp.69-78
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    • 2024
  • Recently, the use of CCTV to prevent crowd accidents has been promoted, but research is needed to compensate for the spatial limitations of CCTV. In this study, pedestrian density was measured using drone footage, and based on a review of existing literature, a threshold of 6.7 people/m2 was selected as the cutoff risk level for crowd accidents. In addition, we conducted a preliminary study to determine drone parameters and found that the pedestrian recognition rate was high at a drone altitude of 20 meters and an angle of 60°. Based on a previous study, we selected a target area with a high concentration of pedestrians and measured pedestrian density, which was found to be 0.27~0.30 per m2. The study shows it is possible to measure risk levels by determining pedestrian densities in target areas using drone images. We believe drone surveillance will be utilized for crowd safety management in the near future.

Automation of Sampling for Public Survey Performance Assessment (공공측량 성과심사 표본추출 자동화 가능성 분석)

  • Choi, Hyun;Jin, Cheol;Lee, Jung Il;Kim, Gi Hong
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.44 no.1
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    • pp.95-100
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    • 2024
  • The public survey performance review conducted by the Spatial Information Quality Management Institute is conducted at the screening rate in accordance with the regulations, and the examiner directly judges the overall trend of the submitted performance based on the extracted sample. However, the evaluation of the Ministry of Land, Infrastructure and Transport, the evaluation trustee shall be specified by random extraction (Random Collection) is specified by the sample. In this study, it analyzed the details of the actual site and analyzed through securing actual performance review data. In addition, we analyzed considerations according to various field conditions and studied ways to apply the public survey performance review sampling algorithm. Therefore, detailed sampling criteria analysis by performance reviewers is necessary. A relative comparison was made feasible by comparing the data for which the real performance evaluation was performed with the outcomes of the Python automation program. This automation program is expected to be employed as a foundation program for the automated application of public survey performance evaluation sampling in the future.

A study of measures to improve the system for the construction of deep tunnels in urban area (도심지 대심도 터널 건설을 위한 제도개선 방안 연구)

  • Hoonki Moon;Joon-Shik Moon;Jongho Shin
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.25 no.6
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    • pp.469-478
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    • 2023
  • The deep tunnel in urban area is a future-oriented construction plan that allows the above-ground space to be used as an eco-friendly park and transportation infrastructure to be constructed in the underground space. However, tunnel construction is often depicted as to cause ground collapse in some media and movies. In fact, while the construction of a deep tunnel in the urban area is underway, the project face with difficulties due to opposition complaints from residents near the route. In this study, we sought to identify perceptions on deep space development and citizen concerns through a public opinion survey regarding deep tunnels. By analyzing laws relevant with the promotion of deep tunnel construction, we reviewed the possibility of public engagement at each stage of the construction and investigated separated surface rights related to compensation for underground space. Through the results of the public opinion survey, it was identified that the concerns of citizens were problems that current technology could solve. Citizen's concerns were improved into a system that confirmed the stability of tunnel construction through public participation, and improvement measures were presented to encourage cooperation from those concerned regarding the establishment of divided superficies.

Perception Survey for Demonstration Service using Drones (드론을 활용한 실증 서비스에 대한 인식 조사)

  • Jina Ok;Soonduck Yoo;Hyojin Jung
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.24 no.1
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    • pp.125-132
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    • 2024
  • The purpose of this study is to discover a drone utilization model tailored to local characteristics, propose directions for building a drone demonstration city based on demand surveys for drone activation, and suggest ways to utilize and support a drone application system. First, according to the survey results, there was a high understanding of and necessity for drone demonstration projects, particularly in addressing urban issues, which were deemed to have a significant impact. Second, based on the analysis of priorities and short- and long-term approaches, disaster-related tasks were evaluated as a priority, requiring an approach through medium- to long-term strategies. Third, it was noted that budgetary considerations emerged as the most critical issue during project implementation. Practitioners and experts expressed willingness to actively introduce drone-based technologies into their work when budget and technology were ready. Budgetary constraints were identified as the most significant obstacle to proper implementation, emphasizing the need for resolution. Fourth, the necessity of demand surveys during project development was identified in certain areas. Demand surveys were deemed essential for drone-based demonstration city construction, and a survey indicated that public leadership in this regard was also necessary. Fifth, concerning approaches in specific areas, the field of safety and disaster management was highlighted as the most crucial for application.

A Simulation of a Small Mountainous Chachment in Gyeoungbuk Using the RAMMS Model (RAMMS 모형을 이용한 경북 소규모 산지 유역의 토석류 모의)

  • Hyung-Joon Chang;Ho-Jin Lee;Seong-Goo Kim
    • Journal of Korean Society of Disaster and Security
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    • v.17 no.1
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    • pp.1-8
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    • 2024
  • In Korea, mountainous areas cover 60% of the land, leading to increased factors such as concentrated heavy rainfall and typhoons, which can result in debris flow and landslide. Despite the high risk of disasters like landslides and debris flow, there has been a tendency in most regions to focus more on post-damage recovery rather than preventing damage. Therefore, in this study, precise topographic data was constructed by conducting on-site surveys and drone measurements in areas where debris flow actually occurred, to analyze the risk zones for such events. The numerical analysis program RAMMS model was utilized to perform debris flow analysis on the areas prone to debris flow, and the actual distribution of debris flow was compared and analyzed to evaluate the applicability of the model. As a result, the debris flow generation area calculated by the RAMMS model was found to be 18% larger than the actual area, and the travel distance was estimated to be 10% smaller. However, the simulated shape of debris flow generation and the path of movement calculated by the model closely resembled the actual data. In the future, we aim to conduct additional research, including model verification suitable for domestic conditions and the selection of areas for damage prediction through debris flow analysis in unmeasured watersheds.

A Consideration on Creativity of the Unconscious: Focusing on a Series of Dreams (무의식의 창조성에 관한 하나의 고찰: 일련의 꿈을 중심으로)

  • Dukkyu Kim
    • Sim-seong Yeon-gu
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    • v.38 no.2
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    • pp.239-268
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    • 2023
  • Humanity has faced destruction(chaos) due to catastrophes (Covid-19, war, earthquake) and awaits a new restoration. For civilizations and individuals, creation or creativity is essential to psychic development. Creativity is the driving force that renews an individual when a new stance and attitude of consciousness or a new adaptation to reality is desperately needed in the depth of the human mind. This article is the result of an exploration of the nature and characteristics of creativity presented by a series of four dreams. First, the definition and form of creativity were explored in the context of religion, mythology, and history of Eastern and Western. While Western mythology refers to creation or creativity originating from God, ancient China viewed creativity as expressed through the interaction of yin and yang, the movement of Tao. In East and West, the form of creation is divided into creation from nothing, creation from matter, and creation through dissolution from the matrix, which psychologically suggests that creativity or creation originates from the unconscious, the seedbed of infinite potential and creative power. Next, with insights from the second dream, the characteristics of creativity were discussed. Creativity occurs through transcendent function and 'going beyond the frame of reference,' that is, 'transgressivity.' Third, the nature of creativity was explored as the creativity of the unconscious aims for regeneration and drives the renewal of Self archetypal images within the collective and individuals. Ultimately, the creativity of the unconscious is the goal of the whole psyche and aims for individuation to become the whole. Realizing the creativity of the unconscious is the fate of humans as the second creator.

Proposal for Research Model of High-Function Patrol Robot using Integrated Sensor System (통합 센서 시스템을 이용한 고기능 순찰 로봇의 연구모델 제안)

  • Byeong-Cheon Yoo;Seung-Jung Shin
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.24 no.3
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    • pp.77-85
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    • 2024
  • In this dissertation, a we designed and implemented a patrol robot that integrates a thermal imaging camera, speed dome camera, PTZ camera, radar, lidar sensor, and smartphone. This robot has the ability to monitor and respond efficiently even in complex environments, and is especially designed to demonstrate high performance even at night or in low visibility conditions. An orbital movement system was selected for the robot's mobility, and a smartphone-based control system was developed for real-time data processing and decision-making. The combination of various sensors allows the robot to comprehensively perceive the environment and quickly detect hazards. Thermal imaging cameras are used for night surveillance, speed domes and PTZ cameras are used for wide-area monitoring, and radar and LIDAR are used for obstacle detection and avoidance. The smartphone-based control system provides a user-friendly interface. The proposed robot system can be used in various fields such as security, surveillance, and disaster response. Future research should include improving the robot's autonomous patrol algorithm, developing a multi-robot collaboration system, and long-term testing in a real environment. This study is expected to contribute to the development of the field of intelligent surveillance robots.