• The Plant Pathology Journal
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• v.34 no.5
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• pp.381-392
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• 2018

Clavibacter michiganensis subsp. michiganesis (Cmm) is a quarantine-worthy pest in $M{\acute{e}}xico$. The implementation and validation of new technologies is necessary to reduce the time for bacterial detection in laboratory conditions and Raman spectroscopy is an ambitious technology that has all of the features needed to characterize and identify bacteria. Under controlled conditions a contagion process was induced with Cmm, the disease epidemiology was monitored. Micro-Raman spectroscopy ($532nm\;{\lambda}$ laser) technique was evaluated its performance at assisting on Cmm detection through its characteristic Raman spectrum fingerprint. Our experiment was conducted with tomato plants in a completely randomized block experimental design (13 plants ${\times}$ 4 rows). The Cmm infection was confirmed by 16S rDNA and plants showed symptoms from 48 to 72 h after inoculation, the evolution of the incidence and severity on plant population varied over time and it kept an aggregated spatial pattern. The contagion process reached 79% just 24 days after the epidemic was induced. Micro-Raman spectroscopy proved its speed, efficiency and usefulness as a non-destructive method for the preliminary detection of Cmm. Carotenoid specific bands with wavelengths at 1146 and $1510cm^{-1}$ were the distinguishable markers. Chemometric analyses showed the best performance by the implementation of PCA-LDA supervised classification algorithms applied over Raman spectrum data with 100% of performance in metrics of classifiers (sensitivity, specificity, accuracy, negative and positive predictive value) that allowed us to differentiate Cmm from other endophytic bacteria (Bacillus and Pantoea). The unsupervised KMeans algorithm showed good performance (100, 96, 98, 91 y 100%, respectively).

• Journal of Korean Society of Disaster and Security
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• v.11 no.2
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• pp.53-60
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• 2018

To diagnosis the local damages of the steel plates, magnetic flux leakage (MFL) method that is known as a adaptable non-destructive evaluation (NDE) method for continuum ferromagnetic members was applied in this study. To analysis the sensitivity according to thickness of steel plate in MFL method based damage diagnosis, several steel plate specimens that have different thickness were prepared and three depths of artificial damage were formed to the each specimens. To measured the MFL signals, a MFL sensor head that have a constant magnetization intensity were fabricated using a hall sensor and a magnetization yoke using permanent magnets. The magnetic flux signals obtained by using MFL sensor head were improved through a series of signal processing methods. The capability of local damage detection was verified from the measured MFL signals from each damage points. And, the peak to peak values (P-P value) extracted from the detected MFL signals from each thickness specimen were compared each other to analysis the MFL based local damage detection sensitivity according to the thickness of steel plate.

• The Korean Journal of Malacology
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• v.27 no.3
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• pp.247-252
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• 2011

The effect of ${\gamma}$-ray irradiation on the color of nucleus and cultured pearls was investigated. After ($^{60}Co$) ${\gamma}$-ray irradiation on the pearl nucleus, its color was altered from brownish to blackish brown or gray depending on irradiation dose. It was clearly found that the all samples are composed of aragonite. ESR spectra were based on the measurement of the paramagnetic species $CO_2$-radicals by the interaction with the ${\gamma}$-ray irradiation in $Mn^{2+}$ containing $CaCO_3$. In this study, we investigated optimal detection method of ${\gamma}$-ray irradiation to establish destructive or non-destructive test for pearl nucleus.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2017.04a
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• pp.156-156
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• 2017

Most crop damages have been occurred by vermin(e.g., wild birds and herbivores) during the period between seeding and the cotyledon level. In this study, to minimize the damage by vermin and acquire the benefits such as protection against weeds and maintenance of water content in soil, immediately vinyl mulching after seeding was devised. Vinyl mulching has been generally covered with black color vinyl, that crop seeding locations cannot be detected by visible light range. Before punching vinyl, non-contact and non-destructive methods that can continuously determine the locations are necessary. In this study, a crop position detection method was studied that uses infrared thermal image sensor to determine the cotyledon position under vinyl mulch. The moving system for acquiring image arrays has been developed for continuously detecting crop locations under plastic mulching on the field. A sliding mechanical device was developed to move the sensor, which were arranged in the form of a linear array, perpendicular to the array using a micro-controller integrated with a stepping motor. The experiments were conducted while moving 4.00 cm/s speed of the IR sensor by the rotational speed of the stepping motor based on a digital pulse width modulation signal from the micro-controller. The acquired images were calibrated with the spatial image correlation. The collected data were processed using moving averaging on interpolation to determine the frame where the variance was the smallest in resolution units of 1.02 cm. For this study, the spline method was relatively faster than the other polynomial interpolation methods, because it has a lower maximum order of formulation when using a system such as the tridiagonal linear equation system which provided the capability of real-time processing. The temperature distribution corresponding to the distance between the crops was 10 cm, and the more clearly the leaf pattern of the crop was visually confirmed. The frequency difference was decreased, as the number of overlapped pixels was increased. Also the wave pattern of points where the crops were recognized were reduced.

• Journal of the Korean Society for Nondestructive Testing
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• v.29 no.5
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• pp.485-492
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• 2009

The thermal fatigue crack(TFC) is one of the life-limiting mechanisms at the nuclear power plant operating conditions. In order to evaluate the structural integrity, various non-destructive test methods such as radiographic test, ultrasonic test and eddy current are used in the industrial field. However, these methods have restrictions that defect detection is possible after the crack growth. For this reason, acoustic emission testing(AET) is becoming one of powerful inspection methods, because AET has an advantage that possible to monitor the structure continuously. Generally, every mechanism that affects the integrity of the structure or equipment is a source of acoustic emission signal. Therefore the noise filtering is one of the major works to the almost AET researchers. In this study, acoustic emission signal was collected from the pipes which were in the successive thermal fatigue cycles. The data were filtered based on the results from previous experiments. Through the data analysis, the signal characteristics to distinguish the effective signal from the noises for the TFC were proven as the waveform difference. The experiment results provide preliminary information for the acoustic emission technique to the continuous monitoring of the structure failure detection.

• Journal of the Korean Society for Nondestructive Testing
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• v.27 no.5
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• pp.426-431
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• 2007

When a high-energy ultrasound propagates through a solid body that contains a crack or a delamination, the two faces of the defect do not ordinarily vibrate in unison, and dissipative phenomena such as friction, rubbing and clapping between the faces will convert some of the vibrational energy to heat. By combining this heating effect with infrared imaging, one can detect a subsurface defect in material in real time. In this paper a realtime detection of the brazing defect of thin Inconel plates using the UIR (ultrasonic infrared imaging) technology is described. A low frequency (23 kHz) ultrasonic transducer was used to infuse the welded Inconel plates with a short pulse of sound for 280 ms. The ultrasonic source has a maximum power of 2 kW. The surface temperature of the area under inspection is imaged by an infrared camera that is coupled to a fast frame grabber in a computer. The hot spots, which are a small area around the bound between the two faces of the Inconel plates near the defective brazing point and heated up highly, are observed. And the weak thermal signal is observed at the defect position of brazed plate also. Using the image processing technology such as background subtraction average and image enhancement using histogram equalization, the position of defective brazing regions in the thin Inconel plates can be located certainly.

• Journal of Korean Traditional Oncology
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• v.16 no.1
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• pp.41-53
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• 2011

Background and Objectives: Iodine is an essential constituent of the thyroid hormones associated with the growth and development of humans and animals as an inorganic nutrition. This element may be accumulated in human blood, tissues and body through the intake of foodstuffs, a beverage, a nutritional supplement and a medicine, among others. The aim of the research is to find out a better medicinal stuff for the thyroid cancer patient who required a low level of iodine diet. Methods: Neutron activation analysis (NAA) used for the iodine analysis is one of nuclear analytical techniques using radiation and radioisotopes and very useful as sensitive analytical technique for performing both qualitative and quantitative multi-elemental non-destructive analysis of major, minor and trace components in variety of environmental and biological materials. In this study, iodine contents in ten kinds of oriental herb medicinal products, which is frequently used to cancer patients are determined by using instrumental neutron activation analysis (INAA) at the HANARO research reactor. The samples prescribed are manufactured as powdered form for taking medicine easily. The analytical quality control is performed to assure an uncertainty of the measurement and to compensate the measured data using a biological certified reference material, NIST SRM 1572, Citrus Leaves. The measured value is $1.89{\pm}0.35mg/kg$, and the relative error is 2.88%, and relative standard deviation is 19 % due to high counting error by small counts of gamma ray spectrum. The standard deviations for other elements such as Cl, K, Mn and Na were in the range of 2 to 8%. Result: The level of iodine contents of Biki-huan, Chungryong-huan and Chungcho-huan, samples detected is less than 6 mg/kg except Hangam Plus sample (more than 210 mg/kg) and six samples were not detected. Iodine in the samples of Shoxiho-tang, Shopunghualhyl-tang, Shocungryong-tang, Banhasaxim-tang, Insampaedox-san and Myunyuk Plus were not measured, but possible level of content can be estimated from the detection limits. In addition, the concentrations of some major elements like Cl, K, Mn, Na, in the samples were determined with the detection limits. Conclusions: Most of samples showed low iodine contents of less than 6 mg/kg but it turned out that most of testing samples can be used to classify the level of iodine diet samples considering the recommended low level of iodine diet 50 ${\mu}g$/day, and a better medicinal stuff for the thyroid cancer patient can be found.

• Journal of the Korean Society of Radiology
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• v.11 no.5
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• pp.321-328
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• 2017

The purpose of the study is to provide basic data for the management of individual exposure and the monitoring of natural radiation dose using D-Shuttle dosimeter (Chiyoda Technol Corporation, Tokyo, Japan). The dose was calculated using D-Shuttle dosimeter. The dose was 1.346 mSv when exposed for 400 days, the annual dose per year was 1.228 mSv/year and the average dose per hour was $0.014{\mu}Sv/hr$. Domestic individual external dose (1.295 mSv/year = Korea average natural individual external dose) and domestic additional dose per year is -0.0663 mSv/year. D-Shuttle is a personal dosimeter for radiation monitoring. It can be used as a very useful dosimeter for ALARA because of its excellent detection capability of radiation, real-time radiation exposure management, alarm function of radiation work, and efficient and easy to use personal radiation dose management.. Radiation monitoring equipment for radiation workers and local residents can be used for radiation monitoring in hospitals, industry, medical sites, nuclear accident areas and hazardous areas in non-destructive areas.

• Corrosion Science and Technology
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• v.17 no.2
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• pp.60-67
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• 2018

The compounds associated with corrosion, in metallic archaeological samples of carbon steel of insular origin were evaluated to establish their degree of deterioration and structural damage against air pollution. The iron phases present in samples of archaeological artifacts were detected by Raman spectroscopy and confocal Raman microcopy. These samples mainly exhibited ing mainly ${\beta}$-FeO(OH) type goethite oxyhydroxides and small amounts of akaganeite ${\alpha}$-FeO(OH) lepidocrocite ${\gamma}$-FeO(OH) due to dominant chloride in a marine environment and non-stoichiometric oxyhydroxides Fe (II + / III +) as indicators of early corrosion. Some parts showed the presence of magnetic maghemite indicating high corrosion. ${\gamma}$-FeO(OH) is a precursor of phases associated with advanced marine corrosion. By studying its decomposition by Raman spectroscopy, it was synthesized with the following sequence: ${\gamma}-FeO(OH){\rightarrow}{\alpha}-FeO(OH)+{\gamma}-FeO(OH)$, ${\rightarrow}{\gamma}-Fe_2O_3+Fe_3O_4$. Ferric compounds provided evidence for the effect of intensity of laser on them, constituting a very useful input for the characterization of oxidation of iron in this type of artifacts. Thus, destructive analysis techniques should be avoided in addition to the use of small amounts of specimen.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2017.04a
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• pp.43-43
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• 2017

종자산업은 농작물 생산에 중요한 역할을 끼치는 좌우하는 요소 중에 하나로, 우량종자의 확보는 농작물 수급에 중요한 역할을 하는 농업부문의 원천산업이다. 오이 녹반 모자이크 바이러스(CGMMV)는 박과류에 가장 많은 피해를 끼치는 바이러스로 종자전염을 방지하고, 우량종자의 공급을 위해서는 감염종자와 비 감염종자의 판별은 필수적이다. 이에 본 연구에서는 초분광 영상 시스템을 이용하여 수박종자의 CGMMV의 감염 및 비 감염종자를 판별할 수 있는 기술을 개발하고자 하였다. 본 연구에서 사용된 바이러스 감염 종자는 CGMMV 바이러스 감염 수박종자를 사용하였으며, 생산된 종자를 초분광 영상 시스템을 통해 스크린 후, RNA를 추출하여 PCR분석법으로 바이러스의 감염유무를 확인하였으며, 이후 바이러스의 감염유무와 획득된 스펙트럼을 비교 분석하여 판별모델을 개발하고 이를 선별 시스템에 적용하였다. 모델개발에 사용된 초분광 영상 기술은 초분광 SWIR(Shortwave infraed : 1000-2500nm)영상 기술이 다. 획득된 초분광 SWIR 영상을 분석한 결과 바이러스 감염 종자가 유의미한 정확도로 판별이 되는 것으로 나타났다. 초분광 SWIR 영상기술이 바이러스 감염종자와 비감염종자를 비파괴적으로 선별하는데 효과적으로 적용이 가능할 것으로 판단된다.