• 제목/요약/키워드: thermal extraction

검색결과 264건 처리시간 0.031초

열화상 이미지 히스토그램의 가우시안 혼합 모델 근사를 통한 열화상-관성 센서 오도메트리 (Infrared Visual Inertial Odometry via Gaussian Mixture Model Approximation of Thermal Image Histogram)

  • 신재호;전명환;김아영
    • 로봇학회논문지
    • /
    • 제18권3호
    • /
    • pp.260-270
    • /
    • 2023
  • We introduce a novel Visual Inertial Odometry (VIO) algorithm designed to improve the performance of thermal-inertial odometry. Thermal infrared image, though advantageous for feature extraction in low-light conditions, typically suffers from a high noise level and significant information loss during the 8-bit conversion. Our algorithm overcomes these limitations by approximating a 14-bit raw pixel histogram into a Gaussian mixture model. The conversion method effectively emphasizes image regions where texture for visual tracking is abundant while reduces unnecessary background information. We incorporate the robust learning-based feature extraction and matching methods, SuperPoint and SuperGlue, and zero velocity detection module to further reduce the uncertainty of visual odometry. Tested across various datasets, the proposed algorithm shows improved performance compared to other state-of-the-art VIO algorithms, paving the way for robust thermal-inertial odometry.

풀화재를 이용한 터널화재 부분배연 모델실험 (Reduced-Scale Experiments of the Partial Smoke Extraction System in Tunnel Fires)

  • 이의주;유용호
    • 한국화재소방학회논문지
    • /
    • 제20권4호
    • /
    • pp.58-64
    • /
    • 2006
  • 부분배연설비를 가지고 있는 침매터널에서 화재시 배연효율을 분석하기위해 풀화재를 이용하여 축소모형실험을 수행하였다. 화재가 발생하였을 때 주위 유동이 없는 경우인 자연배연과 임계속도로 제트팬을 가동하는 강제배연의 경우에 터널내의 온도와 연소가스 농도를 측정하였다. 자연배연에 비해 강제배연은 화재발생 초기에 화원과 터널 내 기류와의 급격한 혼합에 의해 성층화 정도가 미미해지고 보다 낮은 온도를 화원주위에서 얻을 수 있었다. 이러한 급격한 혼합은 터널 상부에 위치한 부분제연 갤러리의 효율을 변화시키는데, 자연배연인 경우에 약 30%의 배연효율이 증가되었다. 일산화탄소 농도계측으로 얻어진 배연효율은 등온기체모델을 사용한 선행연구와 비교하여 거의 일치하는 결과를 얻을 수 있었다. 이러한 결과는 침매터널 화재시 승객의 안전한 대피를 위한 부분배연설비의 최적 운전방안으로 제시된다.

Determination of Palladium in Water Samples Using Cloud Point Extraction Coupled with Laser Thermal Lens Spectrometry

  • Han, Quan;Huo, Yanyan;Yang, Na;Yang, Xiaohui;Zhai, Yunhui;Zhang, Qianyun
    • 대한화학회지
    • /
    • 제59권5호
    • /
    • pp.407-412
    • /
    • 2015
  • A preconcentration procedure for determination of palladium by laser thermal lens spectrometry (TLS) is proposed. It is based on cloud point extraction of palladium(II) ions as 2-(3,5-dichloro-2-pyridylazo)-5-dimethylaminoaniline (3,5-diCl-PADMA) complexes using octylphenoxypolyethoxyethanol (Triton X-114) as surfactant. The effects of various experimental conditions such as pH, concentration of ligand and surfactant, equilibration temperature and time on cloud point extraction were studied. Under the optimized conditions, the calibration graph was linear in the range of 0.15~6 ng mL−1, and the detection limit was 0.04 ng mL−1 with an enrichment factor of 22. The sensitivity was enhanced by 846 times when compared with the conventional spectrophotometric method. The recovery of palladium was in the range of 96.6%~104.0%. The proposed method was applied to the determination of palladium in water samples.

ICA based Thermal Source Extraction and Thermal Distortion Compensation for Machine Tools

  • Lee, Dong-Soo;Park, Jin-Young;Park, Doo-Hyun
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 제어로봇시스템학회 2002년도 ICCAS
    • /
    • pp.91.2-91
    • /
    • 2002
  • $\textbullet$ Machine tools $\textbullet$ Thermal distortion compensation $\textbullet$ Independent component analysis $\textbullet$ Temperature variable reduction $\textbullet$ Thermal distortion modeling $\textbullet$ Hardware Implementation $\textbullet$ Experiments

  • PDF

열영상 기반의 전력선검출 (Power Line Extraction based on thermal Image)

  • 김동욱
    • 한국전자통신학회논문지
    • /
    • 제5권3호
    • /
    • pp.245-250
    • /
    • 2010
  • 본 논문에서는 열영상 기반의 전력선 검출기법이 제안되었다. 전력선 검출 기법은 무인 항공기의 자율 운행을 위해 필요한 기술이다. 하프변환된 데이터를 바탕으로 각도별 분할 기법을 개발하였으며, 이를 바탕으로 그룹핑을 행하고, 마지막으로 전력선을 검출하는 기법을 개발하였다. 제시된 알고리듬에 대한 실험결과에서 다양한 직선성분이 존재하는 영상에서 전력선을 효과적으로 검출할 수 있음을 확인할 수 있었다.

A study of thermolysis of irradiated diamide-containing extraction systems with nitric acid

  • Srvortsov, I.V.;Belova, E.V.;Sokolov, I.P.;Rodin, A.V.;Stefanovsky, S.V.;Mysoedov, B.F.
    • Nuclear Engineering and Technology
    • /
    • 제50권8호
    • /
    • pp.1421-1425
    • /
    • 2018
  • The dynamics of gas release at thermal oxidation of extraction systems on the basis of diamides of dicarbonic acids in fluorinated sulphones with 14 mol/L $HNO_3$ was investigated. The effect of preirradiation of the mixtures with accelerated electrons on the kinetics of their thermolysis was determined. The mixtures were heated in an autoclave at temperatures of 170 and $200^{\circ}C$ and irradiated using an electron accelerator to absorbed doses of 0.1, 0.5, and 1.0 MGy. It has been shown that no conditions for autocatalytic oxidation at thermolysis of extraction mixtures irradiated up to a dose of 1 MGy were developed.

지중 열교환기 설계를 위한 화강암의 열물성 연구 (Thermal Properties of Granite for Installation of Underground Heat Exchanger)

  • 김종찬;이영민;구민호
    • 한국신재생에너지학회:학술대회논문집
    • /
    • 한국신재생에너지학회 2007년도 춘계학술대회
    • /
    • pp.456-459
    • /
    • 2007
  • Thermal conductivities (TC) of 57 Jurassic muscovitic granite samples (KIGAM) and 149 porphyritic granite samples (Yeonki: BE-2, BE-3) were measured with LFA-447. Ranges of TC values are $2.429{\sim}3.878$ W/mK (KIGAM), $2.220{\sim}3.767$ W/mK (Yeonki, BE-2) and $2.019{\sim}3.990$ W/mK (Yeonki, BE-3); arithmetic means are 2.924 W/mK (KIGAM), 2.907 W/mK (Yeonki, BE-2), and 2.881 W/mK (Yeonki, BE-3), respectively. In this study, harmonic mean values were calculated to estimate the average value of TC. Harmonic mean values are 2.883 W/mK (KIGAM), 2.886 W/mK (Yeonki, BE-2), and 2.866 W/mK (Yeonki, BE-3), respectively. Heat extraction rates of a borehole heat exchanger strongly depend on TC values. Heat-extraction rates from re values are expected to be a little lower than 84 W/m in all sites. However, considering ground water flow, it is expected that actual heat extraction rate would be higher than the expected value.

  • PDF

마이크로파에 의한 고무용 충전제로서의 Alumina Powder의 제조에 관한 연구 (Study on the Preparation of Alumina Powders used os a Rubber Filler with a Microwave Extraction System)

  • 박찬영;황은희;민성기
    • Elastomers and Composites
    • /
    • 제33권3호
    • /
    • pp.201-209
    • /
    • 1998
  • 고무배합물의 충진제로 사용되는 알루미나 분말의 제조에 있어서 재래식 및 마이크로파 에너지원에 의하여 황산용액중의 카올린으로 부터 알루미나를 얻는다. 이때 카올린으로부터 알루미나 분말의 최대 추출율은 각각 재래식의 경우는 $80^{\circ}C$, 1M 황산, 180분에서 72.8%이고, 마이크로파 추출 공정의 경우는 $90^{\circ}C$, 1m 황산, 60분에서 $99\%$였다. 또한 추출된 시료는 TG/DTA, XRD, SEM, Atomic Emission Spectroscopy 및 BET법에 의하여 분석하였다..

  • PDF

Hybrid feature extraction of multimodal images for face recognition

  • Cheema, Usman;Moon, Seungbin
    • 한국정보처리학회:학술대회논문집
    • /
    • 한국정보처리학회 2018년도 추계학술발표대회
    • /
    • pp.880-881
    • /
    • 2018
  • Recently technological advancements have allowed visible, infrared and thermal imaging systems to be readily available for security and access control. Increasing applications of facial recognition for security and access control leads to emerging spoofing methodologies. To overcome these challenges of occlusion, replay attack and disguise, researches have proposed using multiple imaging modalities. Using infrared and thermal modalities alongside visible imaging helps to overcome the shortcomings of visible imaging. In this paper we review and propose hybrid feature extraction methods to combine data from multiple imaging systems simultaneously.