• 분석과학
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• 제23권3호
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• pp.295-303
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• 2010

폐수 시료를 이용한 중금속분석용 수질표준물질을 제조하여, 납, 카드뮴, 크롬, 구리, 아연, 망간, 철 등 중금속 7 종에 대해 인증분석 및 불확도 등을 평가하고, 24 개 환경측정분석기관을 대상으로 실험실간 비교실험을 실시하였다. 폐수표준물질의 인증값 및 확장불확도는 KS A ISO 가이드 35(2005)에 의해 도출하였으며, 균질성에 기인한 표준불확도는 특성값의 0.43~2.67%로 나타났다. 환경측정분석기관간 비교실험에서 모든 항목의 비교실험 결과값이 정규분포를 따랐으며, 로버스트 평균값과 폐수표준물질의 인증값과 비교한 결과, 대부분의 항목에서 로버스트 평균값이 인증값보다 낮게 나타났다.

• 월간산업보건
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• 통권66호
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• pp.4-9
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• 1993

• Journal of Electrical Engineering and Technology
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• 제9권3호
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• pp.926-931
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• 2014

This paper presents the torque calculation and parametric analysis of synchronous permanent magnet couplings (SPMCs). Based on a magnetic vector potential, we obtained the analytical magnetic field solutions produced by permanent magnets (PMs). Then, the analytical solutions for a magnetic torque were obtained. All analytical results were extensively validated with the non-linear a two-dimensional (2D) finite element analysis (FEA). In particular, test results such as torque measurements are presented that confirm the analysis. Finally, using the derived analytical magnetic torque solutions, we carried out a parametric analysis to determine the influence of the design parameters on the SPMC's behavior.

• Clinical and Experimental Pediatrics
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• 제53권3호
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• pp.273-285
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• 2010

Completion of the human genome project has allowed a deeper understanding of molecular pathophysiology and has provided invaluable genomic information for the diagnosis of genetic disorders. Advent of new technologies has lead to an explosion in genetic testing. However, this overwhelming stream of genetic information often misleads physicians and patients into a misguided faith in the power of genetic testing. Moreover, genetic testing raises a number of ethical, legal, and social issues. Diagnostic genetic tests can be divided into three primary but overlapping categories: cytogenetic studies (including routine karyotyping, high-resolution karyotyping, and fluorescent in situ hybridization studies), biochemical tests, and DNA-based diagnostic tests. DNA-based testing has grown rapidly over the past decade and includes preandpostnatal testing for the diagnosis of genetic diseases, testing for carriers of genetic diseases, genetic testing for susceptibility to common non-genetic diseases, and screening for common genetic diseases in a particular population. Theoretically, once a gene's structure, function, and association with a disease are well established, the clinical application of genetic testing should be feasible. However, for routine applications in a clinical setting, such tests must satisfy a number of criteria. These criteria include an acceptable degree of clinical and analytical validity, support of a quality assurance program, possibility of modifying the course of the diagnosed disease with treatment, inclusion of pre-and postnatal genetic counseling, and determination of whether the proposed test satisfies cost-benefit criteria and should replace or complement traditional tests. In the near future, the application of genetic testing to common diseases is expected to expand and will likely be extended to include individual pharmacogenetic assessments.

• 분석과학
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• 제15권3호
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• pp.256-262
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• 2002

평균입자크기가 200 ${\mu}m$인 코디어라이트 분말을 사용하여 다공성 필터를 제조한 후, 진공함침법으로 $V_2O_5$, CuO, $LaCoO_3$ 촉매를 담지시킨 후 NO와 $SO_2$ 기체를 촉매 담지 세라믹필터에 동시 통과시키면서 NOx/SOx의 동시제거효율을 측정하였다. 제조된 다공성 필터의 기공률은 61.6%였고, 압축강도는 12.3 MPa이었으며, 면속도 5 cm/sec에서의 차압은 147 Pa이었다. NO와 $SO_2$의 동시제거효율을 분석해 본 결과, 페로브스카이트계 $LaCoO_3$ 촉매의 동시제거효율이 가장 우수함을 확인하였으며, $LaCoO_3$ 촉매의 NO에 대한 제거효율은 90% 이상, $SO_2$에 대해서는 80% 이상이었다.

• 분석과학
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• 제33권6호
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• pp.262-273
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• 2020

식품 중 대표적인 오일 제형인 크릴오일 중에 불소 시험법 개발을 위해 식약처 "식품등 시험법 마련 표준절차에 관한 가이드라인"에 따라서 연소-이온크로마토그래피를 사용하여 크릴오일 중 불소 시험법을 개발하였다. 기존 크릴오일 중 불소 시험법은 전통적인 습식 전위차법이 사용되었으나, 신뢰성이 높지 않았고 국내에서는 이러한 오일 제형에 대해서는 불소 시험을 하는 식품검사기관이 없는 상황이었다. 이에 할로젠 시험법 관련 국가 및 국제표준으로 개발된 시험규격을 확인하였으며, 이 중에 오일 제형에 충분히 적용 가능한 연소-이온크로마토그래프 장비를 선택하여 크릴오일에 적합한 시험법을 개발하였다. 오일 제형의 특성상 시료준비 및 도입 시에 손실 및 각종 방해 (interference) 관련 우려를 사전 검토하여 다양한 실험을 통해서 최적의 시험법을 확립하였다. 개발된 오일 중 불소 시험법을 활용하여 유통되는 크릴오일 제품 11 개를 구입하여 불소함량 시험을 하였으며, 1개 시료를 제외한 대부분 제품들은 시험법에서 제시한 보고서 검출한계 미만으로 불검출을 확인하였다. 또한 불소가 검출되는 부분을 확인하기 위해 진행한 크릴새우 자체 시험한 결과, 크릴 부위에 따라서 농도가 다르긴 하지만, 몸통을 제외한 크릴 껍질부는 약 2,000 mg/kg ~ 3,000 mg/kg의 높은 불소함량이 검출됨을 확인하였다. 이후 확립된 시험법을 국제공인 시험기관 (ISO/IEC 17025) 2 곳에 시료를 의뢰하여 본 수행기관과 시험결과를 비교해 본 결과, 3개 실험실 간에 분산분석 통계처리에서 결과의 유의차가 없음을 확인하였고, 이에 본 내용을 토대로 크릴오일 중 불소함량 분석법 관련 시험법으로 적합함을 확인하였다.

• Smart Structures and Systems
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• 제4권6호
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• pp.809-828
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• 2008

Real-time hybrid testing is an attractive method to evaluate the response of structures under earthquake loads. The method is a variation of the pseudodynamic testing technique in which the experiment is executed in real time, thus allowing investigation of structural systems with time-dependent components. Real-time hybrid testing is challenging because it requires performance of all calculations, application of displacements, and acquisition of measured forces, within a very small increment of time. Furthermore, unless appropriate compensation for time delays and actuator time lag is implemented, stability problems are likely to occur during the experiment. This paper presents an approach for real-time hybrid testing in which time delay/lag compensation is implemented using model-based response prediction. The efficacy of the proposed strategy is verified by conducting substructure real-time hybrid testing of a steel frame under earthquake loads. For the initial set of experiments, a specimen with linear-elastic behavior is used. Experimental results agree well with the analytical solution and show that the proposed approach and testing system are capable of achieving a time-scale expansion factor of one (i.e., real time). Additionally, the proposed method allows accurate testing of structures with larger frequencies than when using conventional time delay compensation methods, thus extending the capabilities of the real-time hybrid testing technique. The method is then used to test a structure with a rate-dependent energy dissipation device, a magnetorheological damper. Results show good agreement with the predicted responses, demonstrating the effectiveness of the method to test rate-dependent components.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 추계학술대회 논문집 전력기술부문
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• pp.101-105
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• 2001

Due to their elastic anisotropy, ultrasonic testing of austenitic welds, frequently used in nuclear power plants, is much more difficult than that of isotropic elements. For accurate testing of austenitic welds, ultrasonic wave phenomena therein must be full understood. This study uses an accurate and effective numerical model, the mass-spring lattice model, for such phenomena. By comparing the numerical results with the corresponding analytical results, it is shown that the model is capable of accurately predicting the generation, reflection, refraction, and scattering phenomena of ultrasonic waves in anisotropic austenite welds. Therefore, the mass-spring lattice model will provide a very useful tool for simulating ultrasonic testing of austenitic welds, and thus will contribute to the enhancement of reliability of such ultrasonic testing.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2001년도 추계학술대회논문집 II
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• pp.665-670
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• 2001

The purpose of this paper is to verify a finite element model of an automotive exhaust system using Modal testing. In general, a lot of finite element models are used in initial design step of automotive development. One of them is a finite element model of an exhaust system. Verification on the finite element model of an automotive exhaust system is indispensable. In this paper, a finite element analysis on the exhaust system using MSC/NASTRAN is carried out, and the results are compared with those obtained by modal testing. By comparing MAC values of the analytical modes with the experimental modes, the finite element model of the automotive exhaust system is verified.

• Steel and Composite Structures
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• 제5권4호
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• pp.259-269
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• 2005

Many slab-on-girder bridges around the world are being assessed because they are approaching the end of their anticipated design lives or codes are permitting higher allowable loads. Current analytical techniques assume that the concrete and steel components act independently, typically requiring full-scale load testing to more accurately predict the remaining strength or endurance of the structure. However, many of the load tests carried out on these types of bridges would be unnecessary if the degree of interaction resulting from friction at the steel-concrete interface could be adequately modeled. Experimental testing confirmed that interface friction has a negligible effect on the flexural capacity of a slab-on-girder beam however, it also showed that interface friction is significant under serviceability loading. This has led to the development of an improved analytical technique which is presented in this paper and referred to as the slab-on-girder mixed analysis service load assessment approach.