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A Study on the Optimal Operation and Policy of the Boryeong Dam Diverion Pipe Line Using the SWAT Model (SWAT 모형을 이용한 보령댐 도수로 운영 방안 및 정책 연구)

  • Park, Bumsoo;Yoon, Hyo Jik;Hong, Yong Seok;Kim, Sung Pyo
    • Journal of Korean Society on Water Environment
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    • v.36 no.6
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    • pp.546-558
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    • 2020
  • While industrialization has provided in abundance, the pollution it creates has caused untold damage to the environment, increasing the frequency and severity of natural disasters through changes in global climate patterns. The World Risk Forum's (WEF) World Risk Report presented the results of a survey of experts from around the world detailing the most influential risk factors over the next decade. Notably, the failure to respond to climate change ranked first and the global water crisis third. The extreme drought in the western Chungnam province was unexpected in 2016. At the time, the water level of Boryeong Dam was drastically decreased due to receiving less than half the average recorded rainfall in the region that year. The Boryeong Dam diversion pipeline has the capacity to solve the water shortage problem between these two regions by providing water from Geumgang to the western part of Chungnam, including Boryeong City. Current weather trends suggest drought is likely to continue in western Chungnam, which uses the Boryeong Dam as an intake source. This makes it necessary to operate Boryeong Dam diversion pipeline in an efficient and effective manner. SWAT is a watershed scale model developed to predict the impact of land management practices on water. The SWAT model was used in this study to evaluate the adequacy of the Boryeong Dam diversion pipeline operational plan by comparing it to present Boryeong Dam diversion pipeline operation. By investigating the number of days required to reach each reservoir stage, we determined that the number of days required to reach the boundary stage was less than that of the current operation. This determination accounts for the caveats that the Boryeong Dam waterway was not operated and only one pump will be operated from October to May of next year. As our results suggest, the most stable operation scenario is to operate two pumps at all times. This can be accomplished by operating two pumps from the caution stage to increase the number of pumps whenever the stage is raised. In addition to the stable operation of the Boryeong Dam pipeline, policy considerations are required with regard to imposing a water use charge on users of the Boryeong Dam region.

Research on Design Capacity Evaluation of Low Impact Development according to Design Criteria (저영향개발 시설 설계 기준에 따른 용량 평가 방법 연구)

  • Im, Jiyeol;Gil, Kyungik
    • Journal of Wetlands Research
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    • v.24 no.1
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    • pp.59-67
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    • 2022
  • The interest in LID facilities is increasing worldwide for recovery of natural water cycle system to destroy by urbanization. However, problems are raised when installation of LID because comprehensive analysis about design capacity adequacy of LID facilities was not conducted completely. In this research, removal efficiency and design volume adequacy of LID facilities were analyzed based on rainfall monitoring data in four LID facilities(Vegetated Swale, Vegetative Filter Strip, Bio-Retention and Permeable Pavement). As a result, group of LID facility designed on WQV was shown higher flow(37%) and pollutants(TSS, BOD, TN and TP) removal efficiencies(20 ~ 37%) than group of LID facility designed on WQF. SA/CA graph was drawn for evaluation of design volume adequacy based on rainfall monitoring data. In this SA/CA graph, coefficient of determination show over 0.5 in all parameter, especially, Flow and TP were show over 0.95. And, 'SA/CA & L/CA' graph considering difference of structure mechanism in LID facility suggested in this research was confirmed that improved coefficient of determination in flow, TSS and TP than SA/CA graph. According to this research results, feasibility of applying 'SA/CA & L/CA' graph for evaluation of design volume adequacy in LID facility, and it is necessary to follow up research for generalization and normalization.

Protective Effects of Traditional Korean Medicine Preparations, Herbs, and Active Compounds on the Blood-brain Barrier in Ischemic Stroke Models (허혈성 뇌졸중 모델에서 혈액-뇌 장벽에 보호효과를 나타내는 한약처방, 한약재 및 활성화합물)

  • Shin, Su Bin;Jang, Seok Ju;Lee, Na Gyeong;Choi, Byung Tae;Shin, Hwa Kyoung
    • Journal of Life Science
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    • v.32 no.7
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    • pp.550-566
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    • 2022
  • Stroke is among the leading causes of death and long-term physical and cognitive disabilities worldwide, affecting an estimated 15 million people annually. The pathophysiological process of stroke is complicated by multiple and coordinated events. The breakdown of the blood-brain barrier (BBB) in people with stroke can significantly contribute to the development of ischemic brain injury. Therefore, BBB disruption is recognized as a hallmark of stroke; thus, it is important to develop novel therapeutic strategies that can protect against BBB dysfunction in ischemic stroke. Traditional medicines are composed of natural products, which represent a promising source of new ingredients for the development of conventional medicines. Indeed, several studies have shown the effectiveness of Korean medicine on stroke, highlighting the value of Korean medicinal treatment for ischemic stroke. This review summarizes the current information and underlying mechanisms regarding the ameliorating effects of the formula, decoction, herbs, and active components of traditional Korean medicine on cerebral ischemia-induced BBB disruption. These traditional medicines were shown to have protective effects on the BBB in many cellular and animal ischemia models of stroke, and experiments in various animal species, such as mice and rats. In addition, they showed brain-protective effects by protecting the BBB through the regulation of tight junction proteins and matrix metalloproteinase-9, reducing edema, neuroinflammation, and neuronal cell death. We hope that this review will help promote further investigation into the neuroprotective effects of traditional Korean medicines and stimulate the performance of clinical trials on Korean herbal medicine-derived drugs in patients with stroke.

Estimates on the Long-term Landform Changes Near Sinduri Beaches (신두리 해빈 장기해안지형변화 탐지 및 추정)

  • Yun, Konghyun;Lee, Chang Kyung;Kim, Gyung Soo
    • Korean Journal of Remote Sensing
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    • v.38 no.6_1
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    • pp.1315-1328
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    • 2022
  • Sinduri beach is a typical sedimentary landform that forms sand dunes due to the influence of the northwest wind in winter. Due to the its large scale and well-developed nature, it has been recognized for conservation value and is currently designated as Natural Monument No. 431, and continuous monitoring is required in terms of the preservation of topographical values. In this study, aerial images, drone images, and drone-based LiDAR data during 36 years were used for long-term topographical change observation of the Sinduri coastal sand dunes located in Taean-gun, Chungcheongnam-do. To implement this, the amount of change in elevation and volume for each period was calculated by applying the difference of Digital Elevation Model (DEM) based on raster calculation using the numerical elevation model generated from the raw data. Also, the amount of change in volume based on probability was calculated using the error propagation law for the intrinsic error of each data source. As a result, it can be seen that from 1986 to 2022, deposition of 35,119 m3 occurred in region of interest A (area: 17,960 m2) and 54,954 m3 of deposition occurred in region of interest B (area: 17,686 m2).

Revision of 22-year Records of Atmospheric Baseline CO2 in South Korea: Application of the WMO X2019 CO2 Scale and a New Baseline Selection Method (NIMS Filter) (지난 22년간 한반도 이산화탄소 배경농도 재산정 연구 - WMO/GAW 척도 변경과 NIMS 온실가스 배경농도 산출기법을 중심으로 -)

  • Seo, Wonick;Lee, Haeyoung;Kim, Yeon-Hee
    • Atmosphere
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    • v.31 no.5
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    • pp.593-606
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    • 2021
  • The Korea Meteorological Administration/National Institute of Meteorological Sciences (KMA/NIMS) has monitored atmospheric CO2 at Anmyeondo (AMY) World Meteorological Organization (WMO) Global Atmosphere Watch Programme (GAW) regional station since 1999, and expanded its observations at Jeju Gosan Suwolbong station (JGS) in the South and at Ulleungdo-Dokdo stations in the East (ULD and DOK) since 2012. Due to a recent WMO CO2 scale update and a new filter (NIMS) to select baseline levels at each station, the 22 years of CO2 data are recalculated. After correction for the new CO2 scale, we confirmed that those corrected records are reasonable within the compatibility goal (±0.1 ppm of CO2) between KMA/NIMS and National Oceanic and Atmosphereic Administration (NOAA) flask-air measurements with the new scale. With the new NIMS filter, CO2 baseline levels are now more representative of the large-scale background compared to previous values, which contained large CO2 enhancements. Atmospheric CO2 observed in South Korea is 4 to 8 ppm greater than the global average while the amplitude of seasonal variation is similar (10~13 ppm) to the amplitude averaged over a comparable latitude zone (30°N-60°N). Variations in CO2 growth rate are also similar, increasing and decreasing similar to global values, as it reflects the net balance between terrestrial respiration and photosynthesis. In 2020, atmospheric CO2 continued increasing despite the COVID-19 pandemic. Even though fossil emission was reduced (around -7% globally), we still emitted large amounts of anthropogenic CO2. Overall, since CO2 has large natural variations and its source was derived from not only fossil fuel but also biomass burning, the small fossil emission reduction could not affect the atmospheric level directly.

Deep Learning Based Rescue Requesters Detection Algorithm for Physical Security in Disaster Sites (재난 현장 물리적 보안을 위한 딥러닝 기반 요구조자 탐지 알고리즘)

  • Kim, Da-hyeon;Park, Man-bok;Ahn, Jun-ho
    • Journal of Internet Computing and Services
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    • v.23 no.4
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    • pp.57-64
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    • 2022
  • If the inside of a building collapses due to a disaster such as fire, collapse, or natural disaster, the physical security inside the building is likely to become ineffective. Here, physical security is needed to minimize the human casualties and physical damages in the collapsed building. Therefore, this paper proposes an algorithm to minimize the damage in a disaster situation by fusing existing research that detects obstacles and collapsed areas in the building and a deep learning-based object detection algorithm that minimizes human casualties. The existing research uses a single camera to determine whether the corridor environment in which the robot is currently located has collapsed and detects obstacles that interfere with the search and rescue operation. Here, objects inside the collapsed building have irregular shapes due to the debris or collapse of the building, and they are classified and detected as obstacles. We also propose a method to detect rescue requesters-the most important resource in the disaster situation-and minimize human casualties. To this end, we collected open-source disaster images and image data of disaster situations and calculated the accuracy of detecting rescue requesters in disaster situations through various deep learning-based object detection algorithms. In this study, as a result of analyzing the algorithms that detect rescue requesters in disaster situations, we have found that the YOLOv4 algorithm has an accuracy of 0.94, proving that it is most suitable for use in actual disaster situations. This paper will be helpful for performing efficient search and rescue in disaster situations and achieving a high level of physical security, even in collapsed buildings.

Performance Measurement of The Hybrid Sheet with Dual Function of Electromagnetic-Shielding and Heat-Dissipating (전자파차폐 및 방열 기능을 가지는 하이브리드시트 성능측정)

  • Ahn, Sung-Su
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.22 no.5
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    • pp.530-536
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    • 2021
  • This paper presents the performance measurement results of a hybrid sheet with both shielding and heat dissipation functions developed by laminating copper mesh sheets and natural graphite sheets, which are used widely as electromagnetic shielding and heat-dissipating materials in electronic devices, without a pressure-sensitive adhesive (PSA). The results were compared by measuring the vertical and horizontal thermal conductivity with two other products to confirm the heat dissipation performance. A radiation emission test confirmed the electromagnetic shielding performance using a 3m electromagnetic anechoic chamber according to the CISPR 11 standard. In the case of vertical thermal conductivity, the proposed hybrid sheet was approximately 8.63 times higher than that of an aluminum sheet with heat dissipation coating and 18.7 times higher than that of a copper sheet laminated with artificial graphite with PSA. The proposed hybrid sheet was approximately 0.64 times that of the sheet, and approximately 1.76 times that of the heat-dissipated aluminum sheet in case of horizontal thermal conductivity. Measurements after applying each sheet in the same heat source revealed the proposed hybrid sheet to have the best heat dissipation performance. The radiation emission test showed that significantly radiation noise had been removed.

Surface Wave Method II: Focused on Passive Method (표면파 탐사 II: 수동 탐사법을 중심으로)

  • Cho, Sung Oh;Joung, Inseok;Kim, Bitnarae;Jang, Hanna;Jang, Seonghyung;Hayashi, Koich;Nam, Myung Jin
    • Geophysics and Geophysical Exploration
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    • v.25 no.1
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    • pp.14-25
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    • 2022
  • The passive surface wave method measures seismic signals from ambient noises or vibrations of natural phenomena without using an artificial source. Since passive sources are usually in lower frequencies than artificial ones being able to ensure the information on deeper geological structures, the passive surface wave method can investigate deeper geological structures. In the passive method, frequency dispersion curves are obtained after data acquisition, and the dispersion curves are analyzed by assuming 1D-layered earth, which is like the method of active surface wave survey. However, when computing dispersion curves, the passive method first obtains and analyzes coherence curves of received signals from a set of receivers based on spatial autocorrelation. In this review, we explain how passive surface wave methods measure signals, and make data processing and interpretation, before analyzing field application cases.

Use of Digital Educational Resources in the Training of Future Specialists in the EU Countries

  • Plakhotnik, Olga;Zlatnikov, Valentyn;Matviienko, Olena;Bezliudnyi, Oleksandr;Havrylenko, Anna;Yashchuk, Olena;Andrusyk, Pavlo
    • International Journal of Computer Science & Network Security
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    • v.22 no.10
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    • pp.17-24
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    • 2022
  • The article proves that the main goal of informatization of higher education institutions in the EU countries is to improve the quality of education of future specialists by introducing digital educational resources into the education process. The main tasks of informatization of education are defined. Digital educational resources are interpreted as a set of data in digital form that is applicable for use in the learning process; it is an information source containing graphic, text, digital, speech, music, video, photo and other information aimed at implementing the goals and objectives of modern education; educational resources on the Internet, electronic textbooks, educational programs, electronic libraries, etc. The creation of digital educational resources is defined as one of the main directions of informatization of all forms and levels of Education. Types of digital educational resources by educational functions are considered. The factors that determine the effectiveness of using digital educational resources in the educational process are identified. The use of digital educational resources in the training of future specialists in the EU countries is considered in detail. European countries note that digital educational resources in professional use allow you to implement a fundamentally new approach to teaching and education, which is based on broad communication, free exchange of opinions, ideas, information of participants in a joint project, on a completely natural desire to learn new things, expand their horizons; is based on real research methods (scientific or creative laboratories), allowing you to learn the laws of nature, the basics of techniques, technology, social phenomena in their dynamics, in the process of solving vital problems, features of various types of creativity in the process of joint activities of a group of participants; promotes the acquisition by teachers of various related skills that can be very useful in their professional activities, including the skills of using computer equipment and various digital technologies.

Detailed Design of Power Conversion Device Hardware for Realization of Fuel Cell Power Generation System (연료전지 발전시스템 구현을 위한 전력변환장치 하드웨어 세부설계)

  • Yoon, Yongho
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.22 no.1
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    • pp.135-140
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    • 2022
  • In addition to the stack that directly generates electricity by the reaction of hydrogen and oxygen, the fuel cell power generation system has a reformer that generates hydrogen from various fuels such as methanol and natural gas. It also consists of a power converter that converts the DC voltage generated in the stack into a stable AC voltage. The fuel cell output of such a system is direct current, and in order to be used at home, an inverter device that converts it into alternating current through a power converter is required. In addition, a DC-DC step-up converter is used to boost the fuel cell voltage to about 30~70V, which is the inverter operating voltage, to about 380V. The DC-DC step-up converter is a DC voltage variable device that exists between the fuel cell output and the inverter. Accordingly, since a constant output voltage of the converter is generated in response to a change in the output voltage of the fuel cell, the inverter can receive constant power regardless of the voltage change of the fuel cell. Therefore, in this paper, we discuss the detailed hardware design of the full-bridge converter, which is the main power source of the inverter that receives the fuel cell output voltage (30~70V) as an input and is applied to the grid among the members of the fuel cell power generation system.