• Applied Science and Convergence Technology
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• v.24 no.6
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• pp.203-214
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• 2015

We have been developing a new label-free nanobio imaging platform using non-linear optics such as Coherent Anti-Stokes Raman Spectroscopy (CARS) and ion beam techniques based on sputtering and scattering such as Secondary Ion Mass Spectrometry (SIMS) and Medium Energy Ion Scattering Spectroscopy (MEIS), which have been widely used for atomic and molecular level analysis of semiconductors and nanomaterials. To apply techniques developed for semiconductors and nanomaterials for biomedical applications, the convergence of nano-analysis and biology were tried. Our activities on label-free nanobio imaging during the last decade are summarized in this review about non-linear optical 3D imaging, ellipsometric interface imaging, SIMS imaging, and TOF-MEIS nano analysis for cardiovascular tissues, collagen thin films, peptides on microarray, nanoparticles, and cell adhesion studies and finally the present snapshot of nanobio imaging and the future prospect are described.

• Investigative Magnetic Resonance Imaging
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• v.25 no.4
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• pp.218-228
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• 2021

Due to their high degree of freedom to transfer and acquire light, fiber optics can be used in the presence of strong magnetic fields. Hence, optical sensing and imaging based on fiber optics can be integrated with magnetic resonance imaging (MRI) diagnostic systems to acquire valuable information on biological tissues and organs based on a magnetic field. In this article, we explored the combination of MRI and optical sensing/imaging techniques by classifying them into the following topics: 1) functional near-infrared spectroscopy with functional MRI for brain studies and brain disease diagnoses, 2) integration of fiber-optic molecular imaging and optogenetic stimulation with MRI, and 3) optical therapeutic applications with an MRI guidance system. Through these investigations, we believe that a combination of MRI and optical sensing/imaging techniques can be employed as both research methods for multidisciplinary studies and clinical diagnostic/therapeutic devices.

• Journal of the Korean Magnetic Resonance Society
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• v.19 no.3
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• pp.124-131
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• 2015

Hyperpolarization methods are the most emerging techniques in the field of magnetic resonance (MR) researches since they make a contribution to overcoming sensitivity limitation of MR spectroscopy and imaging, leading to new fields of researches, real-time in vivo metabolic/molecular imaging and MR analysis of chemical/biological reactions in non-equilibrium conditions. Make use of enormous signal enrichments, it becomes feasible to investigate various chemical and biochemical systems with low ${\gamma}$ nuclei in real-time. This review deals with the theoretical principals of common hyperpolarization methods and their experimental features. In addition, more detailed theories, mechanisms, and applications of dissolution dynamic nuclear polarization (D-DNP) are discussed.

• Journal of Biosystems Engineering
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• v.39 no.3
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• pp.215-226
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• 2014

Recently, spectroscopy has emerged as a potential tool for quality evaluation of numerous food and agricultural products because it provides information regarding both spectral distribution and image features of the sample (i.e., hyperspectral imaging). Spectroscopic techniques reveal hidden information regarding the sample and do so in a non-destructive manner. This review describes the various approaches of spectroscopic modalities, especially hyperspectroscopy and vibrational spectroscopies (i.e., Raman spectroscopy and Fourier transform near infrared spectroscopy) combined with chemometrics for the non-destructive assessment of contaminations and defects in agro-food products.

• Proceedings of the KOSOMBE Conference
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• v.1989 no.05
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• pp.51-54
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• 1989

In last several years, a number of volume localization techniques, such as ISIS, VSE, SPARS and STEAM etc., have been developed for the MR spectroscopy. These localizing techniques, however, require application of several RF pulses for the 3-D volume selection and suffer from T1 and T2 decays due to relatively long RF excitation time. In this paper, we propose a single-shot RF pulse localization technique to achieve the localized 3-D volume selection. This technique combines the cylindrical volume selection technique with a radial gradient coil with single-shot RF pulse and the oscillating selection gradient technique, so thai it minimizes the volume selection time. We report some experimental results obtained with the proposed method which appears promising for 3-D volume imaging and localized spectroscopy.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2008.10a
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• pp.91-94
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• 2008

Newly developed Atom Probe Tomography (APT) technique can provide the highest available spatial resolution, 3D tomography imaging and quantitative chemical analysis in a sub-nm scale. As a complementary technique to APT, Nano-secondary ion Mass Spectroscopy (SIMS) also provides the boron distribution in micro-scale. Therefore, the exact behavior of boron at either grain boundary or grain interior in steels can be investigated by the combination of APT and SIMS techniques from the sub-nanometer scale to the micrometer scale. The results obtained by both APT and SIMS revealed that the boron atoms were mainly segregated to the grain boundaries rather than to the grain interior in the steels containing 50ppm and 100ppm boron. It also found that carbon atoms were segregated at the boron enriched regions, which were thought to be retained austenite phase due to the chemical composition of carbon atoms.

• Electronics and Telecommunications Trends
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• v.33 no.3
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• pp.59-69
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• 2018

Terahertz (THz) imaging and spectroscopy have been developed as non-destructive testing methods for various industrial applications. However, they have not been widely adopted in real applications owing to a high system price and the large size of conventional THz time-domain spectroscopy systems, which are based on ultrashort optical pulse lasers. Recently, various types of compact THz emitters and detectors have become available. As a result, THz non-destructive test (NDT) systems have become viable solutions. Herein, we briefly review the recent advances in THz NDT techniques adopting continuous-wave THz systems, including our recent results of a THz-based waterproof test system and an electrical connection inspection system for car manufacturing.

• Journal of Yeungnam Medical Science
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• v.4 no.1
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• pp.1-15
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• 1987

Magnetic Resonance (M.R.) is rapidly emerging technique that provides high quality images and potentially provides much more diagnostic information than do conventional imaging modalities. M.R.I. is conceptually quite different from currently used imaging methods. The complex nature of M.R.I. allows a great deal of flexibility in image product ion and available information, and key points are as follows. 1. M.R.I. offers a non-invasive technique with which to gene rate in vivo human images without ionizing radiation and with no known adverse biological effects. 2. Imaging mechanism of M.R.I. is quite different from conventional imaging modality and for more accurate diagnostic application, It is necessary for physician to understand imaging mechanism of M.R.I. 3. M.R. makes available basic chemical parameters that may provide to be useful for diagnostic medical imaging and more specific pathophysiologic information which are not available by alternate techniques. 4. M.R. can be produced by number of different methods. This flexibility allows the imaging technique to be applicated for particular clinical purpose. Multiplanar and three dimensional imaging may extend the imaging process beyond the single section available with current CT. 5. Future directions include efforts to; a. Further development of hard ware b. More fasternning scan time c. Respiratory and cardiac gated imaging d. Imaging of additional nuclei except hydrogen e. Further development of contrast media f. M.R. in vivo spectroscopy g. Real time M.R. imaging.

• Journal of Sensor Science and Technology
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• v.27 no.5
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• pp.317-327
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• 2018

Terahertz (THz) time-domain spectroscopy(TDS), imaging techniques, and related systems have become mature technologies, widely used in many universities and research laboratories. However, the development of creative technologies still requires improved THz application systems. A few key points are discussed, including the innovative advances of mode-locking energy-emitting semiconductor lasers and better photoconductive semiconductor quantum structures. To realize a compact, low cost, and high performance THz system, it is essential that THz spectroscopy and imaging technologies are better characterized by semiconductor and nano-devices, both static and time-resolved. We introduce the THz spectroscopy and imaging systems, the OSCAT(Optical Sampling by laser CAvity Tuning) system and the ASOPS(ASynchronous Optical Sampling) system, are constructed by our research team. We report on the THz images obtained from their use.

• Publications of The Korean Astronomical Society
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• v.32 no.1
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• pp.147-149
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• 2017

Since the launch of the Herschel Space Observatory, our understanding about the photo-dissociation regions (PDR) has taken a step forward. In the bandwidth of the Fourier Transform Spectrometer (FTS) of the Spectral and Photometric Imaging REceiver (SPIRE) on board Herschel, ten CO rotational transitions, including J = 4 - 3 to J = 13 - 12, and three fine structure lines, including [$C{\small{I}}$] 609, [$C{\small{I}}$] 370, and [$N{\small{II}}$] $205{\mu}m$, are covered. I present our findings from the FTS observations at the nuclear region of M83, based on the spatially resolved physical parameters derived from the CO spectral line energy distribution (SLED) map and the comparisons with the dust properties and star-formation tracers. This article discusses (1) the potential of using [$N{\small{II}$] 205 and [$C{\small{I}}$] $370{\mu}m$ as star-formation tracers; (2) the excitation mechanisms of warm CO in the nuclear region of M83.