• Nuclear Engineering and Technology
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• 제46권5호
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• pp.595-604
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• 2014

SILER (Seismic-Initiated event risk mitigation in LEad-cooled Reactors) is a Collaborative Project, partially funded by the European Commission in the $7^{th}$ Framework Programme, aimed at studying the risk associated to seismic-initiated events in Generation IV Heavy Liquid Metal reactors, and developing adequate protection measures. The project started in October 2011, and will run for a duration of three years. The attention of SILER is focused on the evaluation of the effects of earthquakes, with particular regards to beyond-design seismic events, and to the identification of mitigation strategies, acting both on structures and components design. Special efforts are devoted to the development of seismic isolation devices and related interface components. Two reference designs, at the state of development available at the beginning of the project and coming from the $6^{th}$ Framework Programme, have been considered: ELSY (European Lead Fast Reactor) for the Lead Fast Reactors (LFR), and MYRRHA (Multi-purpose hYbrid Research Reactor for High-tech Applications) for the Accelerator-Driven Systems (ADS). This paper describes the main activities and results obtained so far, paying particular attention to the development of seismic isolators, and the interface components which must be installed between the isolated reactor building and the non-isolated parts of the plant, such as the pipe expansion joints and the joint-cover of the seismic gap.

• Journal of Magnetics
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• 제21권1호
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• pp.57-60
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• 2016

Non Destructive Testing (NDT) methods that are capable of detecting the wall thinning and defects through insulation and cladding sheets are necessary. In this study we developed a Pulsed Eddy Current (PEC) system to detect wall thinning of ferro magnetic steel pipes covered with 95 mm thick fiber glass thermal insulator and shielded with aluminum plate of thickness 0.4 mm. In order to confirm the thickness change due to wall thinning, two different sensors, a hall sensor and a search coil sensor were used as a detecting element. In both the cases, the experimental data indicates a considerable change in the detected pulse corresponding to the change in sample thickness. The thickness of the tube was made to change such as 2.5 mm, 5 mm and 8 mm from the inner surface to simulate wall thinning. Fast Fourier Transform (FFT) was calculated using window approach and the results were summarized which shows a clear identification of thickness change in the test specimen by comparing the magnitude spectra.

• 한국군사과학기술학회지
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• 제21권6호
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• pp.744-751
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• 2018

In this paper, we propose a fast detection and identification algorithm of chemical gases with a passive FTIR spectrometer. We use a pre-detection algorithm that can reduce the spatial region effectively for gas detection and the candidates of the target. It is possible to remove background spectra effectively from measured spectra with the least-squares method. The CC(Correlation Coefficients) and the SNR(Signal-to-Noise Ratio) methods are used for the detection of target gases. The proposed pre-detection algorithm allows the total process of chemical gas detection to be performed with lower complexity compared with the conventional algorithms. This paper can help developing real-time chemical detection instruments and various applications of FTIR spectrometers.

• Nuclear Engineering and Technology
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• 제53권1호
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• pp.208-215
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• 2021

Cosmic-ray muon scattering tomography (MST) technology is a new radiation imaging technology with unique advantages. As the performance of its image reconstruction algorithm has a crucial influence on the imaging quality, researches on this algorithm are of great significance to the development and application of this technology. In this paper, a fast inspection algorithm based on clustering analysis for the identification of the existence of nuclear materials is studied and optimized. Firstly, the principles of MST technology and a binned clustering algorithm were introduced, and then several simulation experiments were carried out using Geant4 toolkit to test the effects of exposure time, algorithm parameter, the size and structure of object on the performance of the algorithm. Based on these, we proposed two optimization methods for the clustering algorithm: the optimization of vertical distance coefficient and the displacement of sub-volumes. Finally, several sets of experiments were designed to validate the optimization effect, and the results showed that these two optimization methods could significantly enhance the distinguishing ability of the algorithm for different materials, help to obtain more details in practical applications, and was therefore of great importance to the development and application of the MST technology.

• 대한의생명과학회지
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• 제23권2호
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• pp.96-103
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• 2017

Nocardia species (spp.) are opportunistic pathogen in immunocompromised hosts. The genus Nocardia contains more than 70 species. Nocardia takedensis has been recently reported as a new species of the genus Nocardia. In this study, we describes the first clinical isolate of N. takedensis from the skin lesion in Busan, Korea. For the identification of clinical isolate to the species level as N. takedensis, classical methods (colony morphology, biochemical characteristics, and antimicrobial susceptibility), molecular method (16S rRNA gene sequencing), and MS (mass spectrometry) analysis were conducted. Clinical isolates grew slowly on the culture media (5% sheep blood agar and chocolate agar) under 5% $CO_2$ condition. Especially, carotene pigmentation was detected well on the media. Using mass spectrometry, Nocardia isolate was not identified to the species level. However, molecular method based on 16S rRNA sequencing confirmed the isolate as N. takedensis correctly. N. takedensis isolate was partial positive for acid-fast bacilli on the Ziehl-Neelsen method. And it was observed to be resistance to amoxicillin/clavulanic acid and ciprofloxacin. Our results provide useful information to develop optimal identification protocol of N. takedensis in clinical diagnostic laboratories.

• 한국음향학회지
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• 제14권3호
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• pp.37-48
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• 1995

일반화된 완전최소자승법 (generalized total least squares method, GTLS)의 ARMA 시스템 식별에의 적용과 GTLS의 적응알고리듬에 대하여 논한다. 일반화된 완전최소자승법은 일별과 출력을 알고 있는 시스템식별 (system identification)문제에서, 출력이 잡음에 의하여 오염된 경우, 편이되지 않은 해를 구하기 위하여 사용되는 방법이다. 본 논문에서는 먼저 GTLS를 ARMA 시스템 식별에 적용하기 위한 formulation을 하고, 일반화된 완전최소자승법의 일반 해의 성질과 역행렬 정리 (matrix inverse lemma)를 이용하여 적응 GTLS 방법을 제안한다. 다음 제안된 방법을 통하여 시스템식별에 적용하여 그 성능을 평가한다. 또한 GTLS 알고리듬과 제안한 적응 GTLS 알고리듬의 성능을 수학적으로 해석하고 컴퓨터 시뮬레이션을 통하여 이를 검증한다.

• 정보처리학회논문지A
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• 제15A권5호
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• pp.287-294
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• 2008

RFID 시스템에서 리더와 태그는 단일 무선 공유 채널을 갖기 때문에 RFID 수동형 태그를 위한 태그 충돌 중재가 태그 인식을 위한 중요한 이슈이다. 본 논문에서는 태그 충돌 방지를 위한 하이브리드 하이퍼 쿼리 트리 알고리즘($H^{2}QT$, Hybrid Hyper Query Tree)을 제안한다. 제안된 알고리즘은 쿼리 트리를 기반으로 태그가 리더에게 ID를 전송하는 시점을 전송ID 상위 3비트 내의 '1'값을 이용하여 결정한다. 또한 전송 받은 Tag의 상위 3비트는 충돌이 발생하더라도 전송 슬롯에 따라 다르므로 제안한 알고리즘에서 예측이 가능하다. 시뮬레이션을 통한 성능 평가에서 다른 트리 기반 프로토콜에 비해 제안한 알고리즘이 쿼리 횟수에서 높은 성능을 갖는다는 것을 보여준다.

• Advances in nano research
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• 제9권2호
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• pp.113-122
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• 2020

Surface-Enhanced Raman Scattering (SERS) spectroscopy is a multifaceted surface sensitive methodology which exploits spectroscopy-based analysis for various applications. This technique is based on the massive amplification of Raman signals which were feeble previously in order to use them for appropriate identification at qualitative and quantitative in chemical as well as biological systems. This novel powerful technique can be utilized to identify pathogens such as bacteria and viruses. As far as SERS is concerned, one of the most studied problems has been functionalization of SERS active substrate. Metal colloids and nanostructures or microstructures synthesized using noble metals such as Au, Ag and Cu are considered to be SERS active. Silver and gold are extensively used as SERS active substrates due to chemical inertness and stability in air compare to copper. However, use of Cu as a suitable alternative has been taken into account as it is cheap. Herein, we have synthesized air-stable copper microstructures/nanostructures by chemical, electrochemical and microwave-assisted methods. In this paper, we have also discussed the use of as synthesized copper micro/nanostructures as inexpensive yet effective SERS active substrates for the fast identification of micro-organisms like Staphylococcus aureus and Escherichia coli.

• Asian-Australasian Journal of Animal Sciences
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• 제28권9호
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• pp.1235-1243
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• 2015

The goat Capra hircus is one of several economically important livestock in China. Advances in molecular genetics have led to the identification of several single nucleotide variation markers associated with genes affecting economic traits. Validation of single nucleotide variations in a whole-transcriptome sequencing is critical for understanding the information of molecular genetics. In this paper, we aim to develop a large amount of convinced single nucleotide polymorphisms (SNPs) for Cashmere goat through transcriptome sequencing. In this study, the transcriptomes of Cashmere goat skin at four stages were measured using RNA-sequencing and 90% to 92% unique-mapped-reads were obtained from total-mapped-reads. A total of 56,231 putative SNPs distributed among 10,057 genes were identified. The average minor allele frequency of total SNPs was 18%. GO and KEGG pathway analysis were conducted to analyze the genes containing SNPs. Our follow up biological validation revealed that 64% of SNPs were true SNPs. Our results show that RNA-sequencing is a fast and efficient method for identification of a large number of SNPs. This work provides significant genetic resources for further research on Cashmere goats, especially for the high density linkage map construction and genome-wide association studies.

• 한국방재학회 논문집
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• 제10권5호
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• pp.49-54
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• 2010

목조문화재의 화재특성을 보면 화재전파가 빠르고 화재가 발생하면 전소로 이어질 가능성이 큰 특징을 가지고 있다. 그러므로 화재의 예방과 초기 진압을 위해서는 상황을 정확히 인지할 수 있는 기술적인 대응과 더불어 인지된 문제를 조기에 대처할 수 있는 시스템이 필요하다. 이러한 기술을 첨단 유비쿼터스 기술에 의한 상황 감지, 그리고 상황에 따른 빠른 대처 즉, 진압에 활용하기 위해 본 연구에서는 유비쿼터스 센서 네트워크(USN) 기술, 불꽃감지기, 이미지 센서, USN 기반 문화재 방재 응용사례, 오작동 확인시스템 구현 등에 대해서 살펴보고 유비쿼터스형 문화재 방재시스템에 대해 불꽃감지기 오작동 확인시스템에 대해 실험하여 연구결과를 제시하였다.