• Title/Summary/Keyword: Noncontact

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Study of Riverline Change around Sannam Wetland in the Hangang River Estuaty using LANDSAT Image Processing (LANDSAT 위성사진을 활용한 한강하구 산남습지 인근 하안선 변화 연구)

  • Youn, Sukzun;Lee, Samhee;Jang, Changhwan
    • Journal of Wetlands Research
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    • v.23 no.2
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    • pp.154-162
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    • 2021
  • The naturally opened Han river estuary is a place where the flows of the Han river, Imjin river, Yaesung river meet with West Sea of Korea, so the hydrodynamic mechanism(Impact-Response) structure of Han river estuary is complex. Continuous observation and measurement due to the morphological characteristics at the estuary are required to maintain the estuary environment and river management facilities. However, the Sannam wetland(the study area) is in the military operation area. Therefore, Sannam wetland has the limited access under the control from military office. In 2020, there had a natural disaster due to flooding in August and COVID-19, and it made a survey hard. The noncontact survey technique, the analysis of LANDSAT images at Sannam wetland, was applied to analyze riverbed fluctuation and morphological transformation around Sannam wetland. LANDSAT images obtained from EarthExplorer, USGS and analyzed by QGIS. The analysis was performed based on the area and the distance near Sannam wetland. As a result, an erosion was happened on the downstream of the study area, and the upstream of the study area did not have any serious sediment transport. Considering the resolution of LANDSAT images, this noncontect survey technique is applicable to manage the study area. From the analysis of LANDSAT images, it is assumed that the tidal effect is greater than the inflow from the upstream. The pattern change of tidal response causes the damage of the river facilities near the Hangang river estuary.

Development of Surface Velocity Measurement Technique without Reference Points Using UAV Image (드론 정사영상을 이용한 무참조점 표면유속 산정 기법 개발)

  • Lee, Jun Hyeong;Yoon, Byung Man;Kim, Seo Jun
    • Ecology and Resilient Infrastructure
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    • v.8 no.1
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    • pp.22-31
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    • 2021
  • Surface image velocimetry (SIV) is a noncontact velocimetry technique based on images. Recently, studies have been conducted on surface velocity measurements using drones to measure a wide range of velocities and discharges. However, when measuring the surface velocity using a drone, reference points must be included in the image for image correction and the calculation of the ground sample distance, which limits the flight altitude and shooting area of the drone. A technique for calculating the surface velocity that does not require reference points must be developed to maximize spatial freedom, which is the advantage of velocity measurements using drone images. In this study, a technique for calculating the surface velocity that uses only the drone position and the specifications of the drone-mounted camera, without reference points, was developed. To verify the developed surface velocity calculation technique, surface velocities were calculated at the Andong River Experiment Center and then measured with a FlowTracker. The surface velocities measured by conventional SIV using reference points and those calculated by the developed SIV method without reference points were compared. The results confirmed an average difference of approximately 4.70% from the velocity obtained by the conventional SIV and approximately 4.60% from the velocity measured by FlowTracker. The proposed technique can accurately measure the surface velocity using a drone regardless of the flight altitude, shooting area, and analysis area.

The Effect of Breathing Meditation Qigong Therapy on the Recovery of Olfactory Disorders and Voice Handicap Index in Parkinson's Disease Patients (호흡명상기공테라피가 파킨슨병 환자의 후각 및 음성 기능장애 개선에 미치는 효과)

  • So Jung An;Hun Mo Ahn
    • Journal of Korean Medical Ki-Gong Academy
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    • v.23 no.1
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    • pp.10-29
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    • 2024
  • Objective : The purpose of this study is to determine whether An's breathing meditation qigong therapy (ABMQT) delivers bioenergy to the frontal lobe, prefrontal lobe, the olfactory tract in the mesolimbic pathway, olfactory bulb, CV22, CV21, olfactory area and vocal-related areas in Parkinson's disease (PD) patients to help improve olfactory disorders (anosmia) and vocal functions. Methods : The subjects of this study were 4 patients with idiopathic PD (3 males/1 female, 65.0±NA/68.7±10.2 years old). ABMQT was applied once a week, 120 minutes per session for 12 weeks in a non-invasive and noncontact manner, and the test before and after ABMQT application included olfactory impairment test the Korean version of Sniffin' stick test (KVSS), voice acoustic test, aerodynamic test, vocal handicap index (VHI-30), and auditory perception scale test tools. The results before and after the experiment were analyzed assuming a normal distribution, and a chi-square test was performed using a continuity correction, and the significance level was set to p<0.05. And the medical diagnosis and findings of the examiner (doctor in charge) before and after the experiment were described. Results : KVSS was significant as 0.2±0.5 and 9.0±0.0 before and after the experiment. There was no significant difference between the voice acoustic test FO and Jitter, the vocal aerodynamic test MPT, SP, AE, the vocal disorder index test, and the auditory perception test. However, the medical diagnosis findings of four study subjects showed that olfactory disorders, voice disorders, and laryngeal function were improved before and after the application of ABMQT. Conclusions : The breathing meditation qigong program showed significant effects on improving the olfactory disorders (anosmia) and speech function of each study subject. However, to produce meaningful results, it is thought that experiments involving a larger number of research participants are necessary, and additional blood and FMRI tests are conducted to verify metabolic activities and the olfactory neuron signal transmission system.