• Title/Summary/Keyword: IR radiation

Search Result 361, Processing Time 0.027 seconds

Automatic Registration Method for EO/IR Satellite Image Using Modified SIFT and Block-Processing (Modified SIFT와 블록프로세싱을 이용한 적외선과 광학 위성영상의 자동정합기법)

  • Lee, Kang-Hoon;Choi, Tae-Sun
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
    • /
    • v.4 no.3
    • /
    • pp.174-181
    • /
    • 2011
  • A new registration method for IR image and EO image is proposed in this paper. IR sensor is applicable to many area because it absorbs thermal radiation energy unlike EO sensor does. However, IR sensor has difficulty to extract and match features due to low contrast compared to EO image. In order to register both images, we used modified SIFT(Scale Invariant Feature Transform) and block processing to increase feature distinctiveness. To remove outlier, we applied RANSAC(RANdom SAample Concensus) for each block. Finally, we unified matching features into single coordinate system and remove outlier again. We used 3~5um range IR image, and our experiment result showed good robustness in registration with IR image.

Automatic FOD Detection Test Using EO/ IR Laser Light Camera (EO / IR Laser Light 카메라를 이용한 FOD 자동탐지 시험)

  • Shin, Hyun-Sung;Hong, Gyo-Young;Hong, Jae-Beom;Choi, Young-Soo;Kim, Yun-Seob
    • Journal of Advanced Navigation Technology
    • /
    • v.21 no.6
    • /
    • pp.638-642
    • /
    • 2017
  • FOD is a generic term for substances with potential threats that can pose a fatal risk to aircraft. Therefore, FOD should be noted in all areas of the airport. Especially, the method of detecting and collecting FOD in runway and aircraft movements is very low efficiency and economical efficiency of airport operation, so it is essential to develop FOD automatic detection system suitable for domestic environment. As part of the aviation safety technology development project, the development of an automatic detection system for foreign matter in the moving area of the aircraft inside the airport is underway. In this paper, it is confirmed that EO / IR camera is used for detection of foreign objects at Taean Airfield of Hanseo University. EO camera is used during the day and IR camera is used at night.

Variation of Supersonic Aircraft Skin Temperature under Different Mach number and Structure (비행마하수와 형상에 따른 초음속 항공기 표면온도 변화)

  • Cha, Jong Hyun;Kim, Taehwan;Bae, Ji-Yeul;Kim, Taeil;Jung, Daeyoon;Cho, Hyung Hee
    • Journal of the Korea Institute of Military Science and Technology
    • /
    • v.17 no.4
    • /
    • pp.463-470
    • /
    • 2014
  • Stealth technology of combat aircraft is most significant capability in recent air battlefield. As the detector of IR missiles is being developed, IR stealth capability which is evaluated by IR signature level become more important than it was in previous generation. Among IR signature of aircraft from various sources, aerodynamic heating dominates in long-wavelength IR spectrum of $8{\sim}12{\mu}m$. Skin temperature change by aerodynamic heating which is derived by effects of Mach number and structure. The 4th and 5th generation aircraft are selected for calculation of the skin temperature, and its height and velocity in numerical conditions are 10,000 m and Ma 0.9~1.9 respectively. Aircraft skin temperature is calculated by computing convection of fluid and conduction, convection and radiation of surface. As the aircraft accelerates to higher Mach number, maximum skin temperature increases more rapidly than average temperature and temperature distribution changes in more sharp, interactive ways. The 4th generation aircraft whose shape is more complex than that of the 5th generation aircraft have complicated temperature distribution. On the other hand, the 5th generation aircraft whose shape is relatively simple shows plain temperature distribution and lower skin temperature in terms of both average and maximum value.

Image Quality and Lesion Detectability of Lower-Dose Abdominopelvic CT Obtained Using Deep Learning Image Reconstruction

  • June Park;Jaeseung Shin;In Kyung Min;Heejin Bae;Yeo-Eun Kim;Yong Eun Chung
    • Korean Journal of Radiology
    • /
    • v.23 no.4
    • /
    • pp.402-412
    • /
    • 2022
  • Objective: To evaluate the image quality and lesion detectability of lower-dose CT (LDCT) of the abdomen and pelvis obtained using a deep learning image reconstruction (DLIR) algorithm compared with those of standard-dose CT (SDCT) images. Materials and Methods: This retrospective study included 123 patients (mean age ± standard deviation, 63 ± 11 years; male:female, 70:53) who underwent contrast-enhanced abdominopelvic LDCT between May and August 2020 and had prior SDCT obtained using the same CT scanner within a year. LDCT images were reconstructed with hybrid iterative reconstruction (h-IR) and DLIR at medium and high strengths (DLIR-M and DLIR-H), while SDCT images were reconstructed with h-IR. For quantitative image quality analysis, image noise, signal-to-noise ratio, and contrast-to-noise ratio were measured in the liver, muscle, and aorta. Among the three different LDCT reconstruction algorithms, the one showing the smallest difference in quantitative parameters from those of SDCT images was selected for qualitative image quality analysis and lesion detectability evaluation. For qualitative analysis, overall image quality, image noise, image sharpness, image texture, and lesion conspicuity were graded using a 5-point scale by two radiologists. Observer performance in focal liver lesion detection was evaluated by comparing the jackknife free-response receiver operating characteristic figures-of-merit (FOM). Results: LDCT (35.1% dose reduction compared with SDCT) images obtained using DLIR-M showed similar quantitative measures to those of SDCT with h-IR images. All qualitative parameters of LDCT with DLIR-M images but image texture were similar to or significantly better than those of SDCT with h-IR images. The lesion detectability on LDCT with DLIR-M images was not significantly different from that of SDCT with h-IR images (reader-averaged FOM, 0.887 vs. 0.874, respectively; p = 0.581). Conclusion: Overall image quality and detectability of focal liver lesions is preserved in contrast-enhanced abdominopelvic LDCT obtained with DLIR-M relative to those in SDCT with h-IR.

Preparation of Poly(styrene-co-(trimethoxysilyl)propyl methacrylate)-grafted ETFE Films by a Simultaneous Irradiation Grafting Method (방사선을 이용한 스티렌-TMSPM 공중합체가 그래프트된 ETFE 필름의 제조)

  • Sung, Hae-Jun;Sohn, Joon-Yong;Song, Ju-Myung;Shin, Jun-Hwa;Nho, Young-Chang
    • Polymer(Korea)
    • /
    • v.35 no.5
    • /
    • pp.478-482
    • /
    • 2011
  • In this study, several poly(styrene-co-(trimethoxysilyl)propyl methacrylate)-grafted ETFE films were prepared by a simultaneous irradiation grafting method. After mixing of styrene/(trimethoxysilyl)propyl methacrylate(TMSPM) monomers with various solvents, the effects of various irradiation conditions such as total dose, dose rate and monomer concentration on the degree of grafting of the prepared membranes were investigated. Results indicated that the higher degree of grafting was obtained when acetone was used as a solvent. The formation of poly(styrene-co-TMSPM) grafts on the ETFE films was verified using FTIR spectrometry and the distribution of the poly(PTMSPM) graft polymer over the cross-section of the grafted film was confirmed using SEM-EDX instrument.

Evaluation of Absorbed Dose According to the Nanoparticle in Prostate Cancer Brachytherapy (전립선암의 근접치료 시 나노입자에 따른 흡수선량평가)

  • Park, Eun-tae;Lee, Deuk-hee;Im, In-chul
    • Journal of the Korean Society of Radiology
    • /
    • v.12 no.2
    • /
    • pp.167-172
    • /
    • 2018
  • This study evaluated absorbed dose of brachytherapy according to the nanoparticle in prostate cancer which many occurred in Korean man and provided basic data. Absorbed dose evaluation was using MCNPX program which was applied Monte Carlo simulation. Source was applied $^{192}Ir$ which was many using in Korean HDR machine and gold, ferric oxide, gadolinium and iodine nanoparticle were applied. Prostate absorbed dose result was increased when using nanoparticle, in particular gold nanoparticle was the highest result as $3.13E-03J/kg{\cdot}e$. Absorbed dose of surrounding organs and distance was similar between using nanoparticle and non-using nanoparticle. Therefore, brachytherapy was used nanoparticle was increased therapeutic ratio and efficiency of radiation therapy.

Postoperative radiotherapy for endometrial cancer

  • Choi, Eun Cheol;Kim, Jin Hee;Kim, Ok Bae;Byun, Sang Jun;Park, Seung Gyu;Kwon, Sang Hoon
    • Radiation Oncology Journal
    • /
    • v.30 no.3
    • /
    • pp.108-116
    • /
    • 2012
  • Purpose: To investigate the prognostic factors and effectiveness of postoperative radiotherapy alone for endometrial carcinoma. Materials and Methods: Sixty four patients with stage I-III endometrial cancer (EC) treated with postoperative radiotherapy alone between January 1989 and December 2008 at the Keimyung University Dongsan Medical Center were chosen for the present study. Typically, total hysterectomy, salpingo-oophorectomy and lymphadenectomy were performed on the patient's pelvis. Total dose from 50.4 Gy to 63 Gy was irradiated at pelvis or extended field. Thirteen patients were treated with Co-60 or Ir-192 intracavitary radiotherapy. Follow-up periods were from 7 to 270 months, with a median of 56 months. Results: Five year overall survival (OS) rate was 58.7%, respectively. Five year disease-free survival (DFS) rate was 59.2%, respectively. In univariate analysis for OS and DFS, stage, menopausal age, type of operation, serosal invasion, and lymph node involvement were found to be statistically significant. Histologic type was marginally significant. In multivariate analysis for OS and DFS, stage, types of operation, histologic type were also found to be statistically significant. Treatment failure occurred in 14 patients. The main pattern of failure was found to be distant metastasis. Time to distant metastasis was from 3 to 86 months (median, 12 months). There were no grade 3 or 4 complications. Conclusion: Stage, types of operation, and histologic type could be the predictive prognostic factors in patients. We contemplated postoperative radiation as effective and safe treatment method for EC. Additional treatment would be needed to reduce distant metastasis.

A Study on Prediction of Surface Temperature and Reduction of Infrared Emission from a Naval Ship by Considering Emissivity of Funnel in the Mid-Latitude Meterological Conditions (중위도 기상조건에서 함정의 연돌 방사율을 고려한 적외선 복사량 예측 및 감소방안 연구)

  • Gil, Tae-Jun;Choi, Jun-Hyuk;Cho, Yong-Jin;Kim, Tae-Kuk
    • Journal of the Society of Naval Architects of Korea
    • /
    • v.44 no.1 s.151
    • /
    • pp.40-47
    • /
    • 2007
  • This study is focused on developing a software that predicts the temperature distribution and infrared Emission from 30 objects considering the solar radiation through the atmosphere. The solar radiation through the atmosphere is modeled by using the well-known LOWTRAN7 code. Surface temperature information is essential for generating the infrared scene of the object. Predictions of the transient surface temperature and the infrared emission from a naval ship by using the software developed here show fairly good results by representing the typical temperature and emitted radiance distributions expected for the naval ship considered in mid latitude. Emissivity of each material is appeared to be an important parameter for recognizing the target in Infrared band region. The numerical results also show that the low emissivity surface on the heat source can be helpful in reducing the IR image contrast as compared to the background sea.

Synthesis and Biological Evaluation of Novel IM3829 (4-(2-Cyclohexylethoxy)aniline) Derivatives as Potent Radiosensitizers

  • Ahn, Jiyeon;Nam, Ky-Youb;Lee, Sae-Lo-Oom;Ryu, Hwani;Choi, Hyun Kyung;Song, Jie-Young
    • Bulletin of the Korean Chemical Society
    • /
    • v.35 no.12
    • /
    • pp.3623-3626
    • /
    • 2014
  • Nuclear factor-erythroid 2-related factor 2 (Nrf2) regulates the expression of over 200 genes of antioxidant and phase II drug-metabolizing enzymes, and is highly expressed in non-small cell lung cancer (NSCLC). Nine derivatives of 4-(2-cyclohexylethoxy)aniline were designed. Our previous study demonstrated that IM3829 increases radiosensitivity of several lung cancer cells in vitro and in vivo. Here, biological effects of IM3829 derivatives (2a-2i) were evaluated. Compound 2g derivative effectively inhibits mRNA and protein expression of Nrf2 and HO-1. In addition, we observed over two fold enhancement in IR-induced cell death, from $2.90{\pm}0.22$ to $6.02{\pm}0.87$, in H1299 cancer cell-line. Among the nine derivatives, compound 2g derivative exhibited the highest enhancement of radiosensitizing effect via inhibition of Nrf2 activity.

Radiation resistant Characteristics of Fiber Bragg Grating Sensors made with 800-nm femtosecond laser (800nm급 펨토초 레이저로 제작된 FBG 센서의 내방사선 특성)

  • Kim, Jong-Yeol;Lee, Nam-Ho;Jung, Hyun-Kyu;Sohn, Ik-Bu
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
    • /
    • 2017.10a
    • /
    • pp.711-713
    • /
    • 2017
  • Fiber Brag grating sensors were written in standard Ge-doped telecom optical fiber (Corning SMF-28) using an 800nm femtosecond laser and a phase mask. It were exposed to gamma-radiation up to a dose of 100 kGy to evaluate the radiation effect. The fs-FBG-2 sensor showed incomplete optical characteristics during irradiation, but the fs-FBG-1 sensor showed excellent radiation resistance with Bragg wavelength shift(BWS) of less than 10pm at a dose of 100 kGy.

  • PDF