• 한국군사과학기술학회지
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• 제5권3호
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• pp.113-119
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• 2002

A target adaptive guidance(TAG) algorithm is proposed employing the near-zone signal that can be measured from an infrared seeker. The guidance order is composed of a conventional PNG command and an additional command to be calculable from an additional LOS rate between a hot point of target and a required intercept point. The characteristic of the near-zone signal is similar to that of LOS rate that is inversely proportional to the square of time-to-go. Hence the proposed scheme can be applied to real systems with no estimator for time-to-go. From analysis results on the miss distance with perfect missile and perfect seeker, it follows that the proposed TAG algorithm guarantees missile to be ideally guided to the required intercept point. And it is less affected by the TAG start time and a proportional navigation ratio than other TAG schemes using a LOS rate such as a step bias or a ramp bias.

• 천문학회보
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• 제39권2호
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• pp.79.1-79.1
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• 2014

We present the result of near-infrared (near-IR) imaging polarimetry of star-forming regions in the Large Magellanic Cloud (LMC). We compiled near-IR photometric and polarimetric data of N159/160 regions. The photometric and polarimetric data were simultaneously obtained in J, H, and Ks bands using SIRPOL, an imaging polarimeter of the InfraRed Survey Facility (IRSF), in 2007 February. We measured Stokes parameters of point-like sources to derive their degree of polarization and polarization position angles. In this poster, we present polarization properties of these star-forming regions. We also discuss the polarization structure in these regions compared with mid-infrared dust emission structure from the Spitzer SAGE survey.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2012년도 제42회 동계 정기 학술대회 초록집
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• pp.127-127
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• 2012

We carried out the high-resolution dielectric mapping of graphenes on $SiO_2$/Si substrate, using the scattering Apertureless Near-Field Scanning Optical Microscopy (s-ANSOM) in both visible (633 nm) and infrared (3.6 um) wavelengths. In the visible wavelength, the dielectric contrasts are almost proportional to the number of the graphene layers, which indicates that the near-field interaction between the tip and individual graphene layers leads to an image charge oscillation in two-dimension. In the infrared region, on the other hand, we observe unique layer-specific contrasts that do not linearly increase with number of layers. It is attributed to the layer-dependent band- structure of graphenes.

• 한국초지조사료학회지
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• 제9권3호
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• pp.163-167
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• 1989

Near infrared reflectance spectroscopy(NIRS)로 포장를 평가하기 위하여 일건 알파파 건초 5점의 조단백질, NDF, ADF 함량을 측정하였으며 NIRS와 전통적인 문화저방법에 의한 분석치를 비교하였다. 조단백질과 ADF의 량은 NIRS와 화학분석 식간간에 차이가 없었으나 NDF의 함량은 시료번호 2, 4.5에서 유의착(P<0.05)가 있었다.)가 있었다.

• 우주기술과 응용
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• 제1권3호
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• pp.356-363
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• 2021

중적외선을 이용하여 획득한 영상은 상온 부근의 온도 측정에는 적당하지 않다는 것이 교과서적 상식이었으나, 최근 중적외선 센서를 이용한 위성 영상을 살펴보면 중적외선 센서를 이용하여 측정한 결과물도 상온 부근의 온도를 측정할 수 있다는 가능성을 보여주고 있다. 본 논문에서는 중적외선 센서를 가지는 위성영상의 상온 온도 정보 추출 가능성 및 정확도에 대해 살펴보고자 한다. 논문에서 검토된 중적외선 위성영상은 상온 부분의 온도를 잘 표시하였으며, 측정된 온도의 절대값으로서의 신뢰성에 관해서는, 태양광의 지표면 직접 반사에 의한 열전달량 영향과 대기에서 흡수되는 적외선 대기 흡수량의 영향은 비교적 작거나 일정한 값으로 볼 수 있지만, 비접촉식 온도계의 한계인 물성치의 의한 복사 계수(emissivity)의 불확실성 문제는 여전히 해결해야할 문제로 남아 있게 되었다.

• 천문학논총
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• 제27권4호
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• pp.161-164
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• 2012

We performed a spectroscopic survey for cometary volatiles with the Infrared Camera onboard the Japanese infrared satellite AKARI. The observations were carried out in the near-infrared wavelength range in the period from 2008 June to 2010 January. In this paper, we summarize the observations and results of the AKARI survey for the mixing ratios of major volatiles in comets. We derived the $2.5-5{\mu}m$ spectra of 18 comets including both Oort cloud comets and Jupiter-family comets. Prominent emission bands in the observed spectra are the fundamental vibrational bands of water ($H_2O$) at $2.7{\mu}m$ and carbon dioxide ($CO_2$) at $4.3{\mu}m$. The fundamental vibrational band of carbon monoxide (CO) at $4.7{\mu}m$ and the broad emission feature probably related to C-H bearing molecules can also be recognized around the $3.4-3.5{\mu}m$ region in some comets. We detect $CO_2$ in 17 out of 18 comets, and derived gas production rate ratios of $CO_2$ with respect to $H_2O$ in 17 comets. We detect a reliable CO emission band only in three of the comets. Our data set provides the largest homogeneous database of $CO_2/H_2O$ ratios in comets obtained so far.

• 천문학논총
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• 제27권4호
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• pp.181-182
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• 2012

Using the AKARI mid-infrared all-sky survey catalogue, we are searching for debris disks which are important objects as an observational clue to on-going planetary system formation. Debris disk candidates are selected through a significant excess of the measured flux over the predicted flux for the stellar photospheric emission at $18{\mu}m$. The fluxes were originally estimated based on the near-infrared spectral energy distributions (SEDs) of central stars constructed from the 2MASS J-, H-, and Ks-band fluxes. However, we found that in many cases the 2MASS photometry has large errors due to saturation in the central part of a star image. Therefore we performed follow-up observations with the IRSF 1.4m near-infrared telescope in South Africa to obtain accurate fluxes in the J-, H-, and Ks-bands. As a result, we have succeeded in improving the SEDs of the central stars. This improvement of the SEDs allows us to make more reliable selection of the candidates.

• 한국근적외분광분석학회:학술대회논문집
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• 한국근적외분광분석학회 2001년도 NIR-2001
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• pp.1531-1531
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• 2001

A novel technique has been developed to observe the three-dimensional (3-D) distribution of chemical components in biological materials using both automatic sectioning microtome and infrared microscope. The 3-D image was reconstructed based on the relationship between the content and the absorbancy of specified wavelength for chemical components. By using the automatic sectioning microtome, the kernel of rice sample fixed in paraffin was sequentially sliced with the thickness of $5\;\mutextrm{m}$ after pasting the sliced sectional specimens on an adhesive tape. The chemical components of the specimens, which are placed on the X-Y controlling stage with positioning accuracy of ${\pm}10\;\mutextrm{m}$, were analyzed by the infrared microscope. The 3-D images demonstrated that the zonal protein about $200\mutextrm{m}$ in width was observed mainly at the outer parts of a rice particle, and carbohydrates entirely. These images can be observed by choosing arbitrary observation angle. The result indicated that the developed technique could be applied 3-D information to investigate intrinsic chemical components but also residual pesticides as well as bacteria contamination for agricultural produce.

• 천문학논총
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• 제22권3호
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• pp.55-61
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• 2007

The KASINICS (Korea Astronomy and Space science Institute Near Infrared Camera System) is a ground-based near-infrared (NIR) imaging instrument. KASINICS has offner relay optics to reduce unwanted infrared light. For the offner optics, we adopted an ultra precision machining process which is installed at KBSI (Korea Basics Science research Institute). Since the offner relay optics is made of aluminum 6061 metal material, we did several tests to reach the specification. We found that a 0.497mm radius nose bite and 220m/min machining speed are best tool and condition to make this offner optics with the precision machine. In this paper, we report the technical method of ultra precision machining and results of the KASINICS offner optics.

• 천문학회보
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• 제40권1호
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• pp.54.3-54.3
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• 2015

To probe the star formation in local and early Universe, the NISS with a capability of imaging spectroscopy in the near-infrared is being developed by KASI. The main scientific targets are nearby galaxies, galaxy clusters, star-forming regions and low background regions. The off-axis optical design of the NISS with 15cm aperture was optimized to obtain a wide field of view (FoV) of $2deg.{\times}2deg.$ as well as a wide spectral coverage from 0.9 to $3.8{\mu}m$. The opto-mechanical structure was designed to be safe enough to endure in both the launching condition and the space environment. The dewar will operate $1k{\times}1k$ infrared sensor at 80K stage. The NISS will be launched in 2017 and explore the large areal near-infrared sky up to $200deg.^2$ in order to get both spatial and spectral information for astronomical objects. As an extension of the NISS, KASI is planning to participate in a new small space mission together with NASA. The promising candidate, SPHEREx (Spectro-Photometer for the History of the Universe Epoch of Reionization, and Ices Explorer) is an all-sky survey satellite designed to reveal the origin of the Universe and water in the planetary systems and to explore the evolution of galaxies. Though the survey concept is similar to that of the NISS, the SPHEREx will perform the first near-infrared all-sky imaging spectroscopic survey with the wider spectral range from 0.7 to $5{\mu}m$ and the wider FoV of $3.5deg.{\times}7deg.$ Here, we report the current status of the NISS and introduce new mission for the near-infrared imaging spectroscopic survey.