This study applied a camera trapping method to investigate species diversity of birds and mammals in Jingwan-dong Wetland located in Bukhansan National Park, Seoul, Korea. The objectives of this study were to (1) verify the efficiency of the camera trapping method through a combination of literature and observation surveys, and to (2) propose it as an effective monitoring method to assessing changes in biodiversity. From February 2022 to June 2022, a total of six cameras were installed for 121 days to conduct camera trapping in three aquatic environments. As a result, a total of 14,742 videos were obtained with a data acquisition rate of 59.2%. Analysis of the data identified a total of 20 families and 47 species of birds with 7 families and 8 species of mammals. When previous field observation data compiled from the past 10 years starting from 2011 were analyzed, a total of 33 families and 90 species of birds with 5 families and 6 species of mammals were identified. Camera trapping in Jingwan-dong Wetland recorded species list, including 3 families and 3 species of bird and 2 families and 2 species of mammal not observed in the past decade. Thus, camera trapping, which complements temporal limitations of field survey, can be an effective monitoring method for rapidly changing biodiversity if spatial limitations are improved. Resulting species lists can serve as a basis for future restoration and management plans.
운량은 천체 관측을 지속하는 데에 중요한 요소 중 하나이다. 과거에는 관측자가 날씨를 직접 판단할 수밖에 없 었으나, 원격 및 자동 관측 시스템의 개발로 관측자의 역할이 상대적으로 줄어들었다. 또한 구름의 다양한 형태와 빠른 이동 때문에 자동으로 운량을 판단하는 것은 쉽지 않다. 이 연구에서는 기계학습 기반의 파이썬 모듈인 “cloudynight” 을 밀양아리랑우주천문대의 전천 영상에 적용하여 운량을 모니터링하는 프로그램을 개발하였다. 전천 영상을 하위 영역 으로 나누어 각 39,996개 영역의 16개의 특징을 학습하여 기계학습 모델을 생성하였다. 검증 표본에서 얻은 F1 점수는 0.97로, 기계학습 모델이 우수한 성능을 가짐을 보여준다. 운량(“Cloudiness”)은 전체 하위 영역 개수 중 구름으로 식별 된 하위 영역 개수의 비율로 계산하며, 운량이 지난 30분 동안 0.6을 초과할 때 관측을 중단하도록 자동 관측 프로그 램 규칙을 정하였다. 이 규칙을 따를 때, 기계학습 모델이 운량을 오판하여 관측에 영향을 미치는 경우는 거의 발생하 지 않았다. 본 기계학습 모델을 통하여, 밀양아리랑우주천문대 0.7 m 망원경의 성공적인 자동 관측을 기대한다.
In this paper, the key assembly of the recently developed light machine gun-Ⅱ sighting device was identified as prone to experiencing horizontal noise caused by unstable voltage fluctuations under high-temperature conditions during the defense environmental stress screening test. The primary objective ot this study is to address the issue of horizontal noise through circuit analysis and device parameter tuning, aiming to eliminate its presence.
The Wide-Angle Polarimetric Camera (PolCam) is installed on the Korea’s lunar orbiter, Danuri, which launched on August 5, 2022. The mission objectives of PolCam are to construct photometric maps at a wavelength of 336 nm and polarization maps at 461 and 748 nm, with a phase angle range of 0◦–135◦ and a spatial resolution of less than 100 m. PolCam is an imager using the push-broom method and has two cameras, Cam 1 and Cam 2, with a viewing angle of 45◦ to the right and left of the spacecraft’s direction of orbit. We conducted performance tests in a laboratory setting before installing PolCam’s flight model on the spacecraft. We analyzed the CCD’s dark current, flat-field frame, spot size, and light flux. The dark current was obtained during thermal / vacuum test with various temperatures and the flat-field frame data was also obtained with an integrating sphere and tungsten light bulb. We describe the calibration method and results in this study.
The GMT-Consortium Large Earth Finder (G-CLEF) is the first instrument for the Giant Magellan Telescope (GMT). G-CLEF is a fiber feed, optical band echelle spectrograph that is capable of extremely precise radial velocity measurement. G-CLEF Flexure Control Camera (FCC) is included as a part in G-CLEF Front End Assembly (GCFEA), which monitors the field images focused on a fiber mirror to control the flexure and the focus errors within GCFEA. FCC consists of an optical bench on which five optical components are installed. The order of the optical train is: a collimator, neutral density filters, a focus analyzer, a reimager and a detector (Andor iKon-L 936 CCD camera). The collimator consists of a triplet lens and receives the beam reflected by a fiber mirror. The neutral density filters make it possible a broad range star brightness as a target or a guide. The focus analyzer is used to measure a focus offset. The reimager focuses the beam from the collimator onto the CCD detector focal plane. The detector module includes a linear translator and a field de-rotator. We performed thermoelastic stress analysis for lenses and their mounts to confirm the physical safety of the lens materials. We also conducted the global structure analysis for various gravitational orientations to verify the image stability requirement during the operation of the telescope and the instrument. In this article, we present the opto-mechanical detailed design of G-CLEF FCC and describe the consequence of the numerical finite element analyses for the design.
By developing plasma torch melting technology in 1996, our company has developed the first generation 150 kW (’96~’02), the second generation 500 kW (’08~’12), and the third generation MW plasma torch melting facility (’14~’18), and completed facility upgrading (’20~’23). The MW plasma torch melting facility is equipped with CCTV to monitor waste input, melting, torch integrity, and melt discharge. The lens is installed inside a metal housing made of stainless steel to prevent damage caused by external impacts and high temperatures, and supplies nitrogen to prevent cooling and lens contamination. As a result of the demonstration test, as the temperature inside the melting furnace increased after starting the plasma torch, the resolution decreased along with noise in the CCTV, and facility monitoring was difficult due to high temperatures and foreign substances (fume). Based on the test results, CCTV was changed to a non-insertion type that was not directly exposed to high temperatures, and a filter (quartz) was additionally applied to monitor the melt smoothly. As a result of applying the newly manufactured CCTV to the demonstration test, smooth monitoring ability was confirmed even at normal operating temperature (above 1,500°C). Through this facility improvement, the operation convenience of the plasma torch melting facility has been secured, and it is expected that it will be able to operate stably during long-term continuous operation in the future.
Background: Virtual reality (VR) programs based on motion capture camera are the most convenient and cost-effective approaches for remote rehabilitation. Assessment of physical function is critical for providing optimal VR rehabilitation training; however, direct muscle strength measurement using camera-based kinematic data is impracticable. Therefore, it is necessary to develop a method to indirectly estimate the muscle strength of users from the value obtained using a motion capture camera.
Objects: The purpose of this study was to determine whether the pedaling speed converted using the VR engine from the captured foot position data in the VR environment can be used as an indirect way to evaluate knee muscle strength, and to investigate the validity and reliability of a camera-based VR program.
Methods: Thirty healthy adults were included in this study. Each subject performed a 15-second maximum pedaling test in the VR and built-in speedometer modes. In the VR speedometer mode, a motion capture camera was used to detect the position of the ankle joints and automatically calculate the pedaling speed. An isokinetic dynamometer was used to assess the isometric and isokinetic peak torques of knee flexion and extension.
Results: The pedaling speeds in VR and built-in speedometer modes revealed a significantly high positive correlation (r = 0.922). In addition, the intra-rater reliability of the pedaling speed in the VR speedometer mode was good (ICC [intraclass correlation coefficient] = 0.685). The results of the Pearson correlation analysis revealed a significant moderate positive correlation between the pedaling speed of the VR speedometer and the peak torque of knee isokinetic flexion (r = 0.639) and extension (r = 0.598).
Conclusion: This study suggests the potential benefits of measuring the maximum pedaling speed using 3D depth camera in a VR environment as an indirect assessment of muscle strength. However, technological improvements must be followed to obtain more accurate estimation of muscle strength from the VR cycling test.
Image-oriented information is becoming increasingly important on social networking services (SNS); the background of this trend is the popularity of selfies. Currently, camera applications using augmented reality (AR) and artificial intelligence (AI) technologies are gaining traction. An AR camera app is a smartphone application that converts selfies into various interesting forms using filters. In this study, we investigated the change of keywords according to the time flow of selfies in Goolgle News articles through semantic network analysis. Additionally, we examined the effects of using an AR camera app on appearance satisfaction and self-esteem when taking a selfie. Semantic network analysis revealed that in 2013, postings of specific people were the most prominent selfie-related keywords. In 2019, keywords appeared regarding the launch of a new smartphone with a rear-facing camera for selfies; in 2020, keywords related to communication through selfies appeared. As a result of examining the effect of the degree of use of the AR camera app on appearance satisfaction, it was found that the higher the degree of use, the higher the user’s interest in appearance. As a result of examining the effect of the degree of use of the AR camera app on self-esteem, it was found that the higher the degree of use, the higher the user’s negative self-esteem.
본 연구에서는 드론을 활용한 변위계측에서 드론의 회전진동 보정을 위해 드론 내부의 가속도계를 이용하는 방법 대신에 드 론 영상 내부의 변위가 발생하지 않는 고정점을 활용한 드론의 회전진동 보정방법을 제안하고자 한다. 영상 내부의 고정점을 활용한 드론 회전진동 보정을 위한 예비 연구로서, 카메라를 고정시킨 후 타겟을 회전하여 회전각도를 측정하는 실험과 회전하는 카메라를 통 해 변위가 발생하는 모형구조물의 변위를 계측하는 실험을 통해 카메라의 회전진동이 발생하는 경우 변위 계측정확도를 검증하였다. 변위가 3mm 이하로 발생 시 카메라 진동이 발생하였을 때 계측 신뢰도가 낮은 반면, 변위가 3mm를 초과하여 발생한 경우 비교적 정 확하게 계측되었다.
자율운항선박이 상용화되어 연안을 항해하기 위해서는 해상의 장애물을 탐지할 수 있어야 한다. 연안에서 가장 많이 볼 수 있 는 장애물 중의 하나는 양식장의 부표이다. 이에 본 연구에서는 YOLO 알고리즘을 이용하여 해상의 부표를 탐지하고, 카메라 영상의 기하 학적 해석을 통해 선박으로부터 떨어진 부표의 거리와 방위를 계산하여 장애물을 시각화하는 해상물체탐지시스템을 개발하였다. 1,224장 의 양식장 부표 사진으로 해양물체탐지모델을 훈련시킨 결과, 모델의 Precision은 89.0 %, Recall은 95.0 % 그리고 F1-score는 92.0 %이었다. 얻 어진 영상좌표를 이용하여 카메라로부터 떨어진 물체의 거리와 방위를 계산하기 위해 카메라 캘리브레이션을 실시하고 해상물체탐지시 스템의 성능을 검증하기 위해 Experiment A, B를 설계하였다. 해상물체탐지시스템의 성능을 검증한 결과 해상물체탐지시스템이 레이더보 다 근거리 탐지 능력이 뛰어나서 레이더와 더불어 항행보조장비로 사용이 가능할 것으로 판단된다.
Prior to dismantling a nuclear facility, full site characterization should be carried out to identify basic data for various stages of decommissioning, such as deregulation of sites and structures, selection of decontamination technology, decommissioning methods, and waste management and disposal. Radiological characterization is implemented through information collection, on-site measurement, sampling and analysis, and theoretical calculations and proven codes for radioactive material at the time of decommissioning of the nuclear facility. There are issues in that it takes a lot of time and money to collect and analyze samples for characterization of contaminated sites and radioactive structures. Therefore, in the entire process of decommissioning a nuclear facility, a technology that can quickly measure the radiological characteristics of various decommissioning objects and wastes on site is required. In this project, the utilization of gamma cameras that can be analyzed in the field for quick and accurate characteristic evaluation at the dismantling site was studied. A gamma camera, iPIX from Canberra (Now it became Mirion Technology), was tested in this study. It is a unique gamma imager, which have a CdTe sensor with TIMEPIX chip and a coded aperture collimator, quickly locates and identifies low to high level radioactive sources from a distance while estimating the dose rate at the measurement point in real time. It also can be combined with CZT sensor which called iPIX-NID (nuclide Identification) provides users with clear understanding of radionuclides presence with no need of any spectroscopic knowledge. iPIX with iPIX-NID convert the gamma camera into a hot-spot detector with radionuclide information. To verify the applicability of a gamma camera in Nuclear power plant, it was implemented to Kori unit-1 which was permanently shut down from 2017. Various Systems were observed at restricted area including reactor cooling system, boron recovery system, residual heat removal system, containment spray system, and etc. The locations of hot spots were clearly revealed by iPIX and these results can be used for selecting the locations of destructive samples and help to decide the conservative decision making. Condensate water systems in turbine building were also observed by a gamma camera and showed no nuclide. Based on this preliminary gamma camera applications, further investigation and tests will be carried out to Kori Unit-1.
본 논문은 선박 기관실 내의 효율적인 감시를 위한 팬-틸트-줌(PTZ) 카메라 기반의 모니터링 시스템의 설계 방법을 다룬다. 선
박 기관실에는 여전히 전통적인 아날로그 계기들을 사용하는 곳이 많고, 침수나 화재 등 안전과 밀접하게 관련된 사각지대들이 다수 존
재한다. 이러한 감시 개소들에 대하여 비교적 빠른 주기로 넓은 범위를 보장하는 카메라 기반 감시 시스템은 선박의 안전을 강화시킬 수
있는 효과적인 대안이 될 수 있다. 이에 본 연구에서는 기존 PTZ 카메라의 기능들을 소프트웨어적 방법으로 더욱 강화시킨 형태의 모니
터링 시스템을 제안한다. 보다 구체적으로는 카메라제어 모듈, 위치등록 모듈, 순회제어 모듈, 멀티뷰 영상재구성 모듈로 구성된 모니터
링 시스템의 설계 방법을 제안하고, 제안된 방법은 기관실 환경에서의 실험을 통해 그 효용성을 평가한다.