• Title/Summary/Keyword: reference materials

Search Result 1,962, Processing Time 0.034 seconds

Estimation of Pyrolysis Properties for Fire Propagation Analysis of Furniture Materials (가구소재의 화재전파해석을 위한 열해리 물성 평가)

  • Kim, Sung-Chan
    • Fire Science and Engineering
    • /
    • v.27 no.4
    • /
    • pp.41-46
    • /
    • 2013
  • The present study has been conducted to investigate the reaction kinetics and pyrolysis parameters for flame propagation analysis of furniture material components. TGA measurement for component materials such as MDF (medium density fiberboad) panel including coating material, synthetic leather and foam cushion are performed under maximum temperature of $600^{\circ}C$ and heating rate of $10^{\circ}C/min$. The results of TGA have shown that the peak temperature of MDF panel was $324^{\circ}C$ and the initial peak temperature of coating material decreased by $270{\sim}280^{\circ}C$. In the case of synthetic leather and foam materials, the reference temperature and reference rate depend on the type of polymer consisting the sample, the initial kinetic characteristics was classified into 2 categories of about $270^{\circ}C$ and $420^{\circ}C$ of reference temperature for the tested synthetic materials. The present study showed the pyrolysis parameters of reference temperature and reference rate proposed by Lyon to evaluate the pre-exponential factor and activation energy. The present study can contribute to improve the reliability of computational fire analysis and enhance the understanding of fire propagation phenomena based on the thermal properties study of material.

Construction of an ISO 15926-based Reference Data Server Using iRINGTools and Its Application (iRINGTools를 활용한 ISO 15926 기반 기자재 참조 데이터 서버의 구축과 활용)

  • Kim, Bongcheol;Park, Sangjin;Kwon, Soonjo;Byon, Su-jin;Mun, Duhwan;Han, Soonhung
    • Korean Journal of Computational Design and Engineering
    • /
    • v.22 no.2
    • /
    • pp.150-161
    • /
    • 2017
  • Effective data exchange among the diverse stakeholders participating in a process plant project is an important issue. ISO 15926 is an international standard to support sharing and integrating of process plant data. iRINGTools is an ISO 15926-based tool used to exchange plant data. To exchange plant data using iRINGTools, the mapping between the data model of a commercial system and ISO 15926 should be preceded. To accomplish this, types and properties of equipment and materials used for plant design should be predefined and these data should be represented as user-defined reference data complying with ISO 15926. Besides, the user-defined reference data should be serviced by a reference data server such that iRINGTools searches reference data from the server and utilizes the data for the model mapping. In this paper, we present a method to construct a reference data server and use it for the model mapping in iRINGTools. The proposed method is verified through experiments of exchanging specifications data of equipment and materials using iRINGTools.

Effect of Initial (Reference) Welding Current for Adaptive Control and It's Optimization to Secure Proper Weld Properties in Resistance Spot Welding

  • Ashadudzzaman, Md.;Choi, Il-Dong;Kim, Jae-Won;Nam, Dae-Geun;Park, Yeong-Do
    • Journal of Welding and Joining
    • /
    • v.33 no.6
    • /
    • pp.13-20
    • /
    • 2015
  • Many automotive companies are endeavoring to improve the quality of resistance spot welding by updating body-in-white (BIW) production line with adaptive control spot welding system to compensate the process disturbances such as gap, electrode wear, oxidized surfaces, poor fit up and adhesive etc. Most of the commercial adaptive weld controllers require proper "Initial Welding Schedule" or "Reference weld" to achieve compensation in welding parameters during real time welding. In this study, the compensation of a commercial adaptive weld controller had been observed and analyzed thoroughly for various process disturbances to find optimal initial welding schedule. It was observed that 90 percent of the expulsion current in constant current control as reference welding schedule conferred the maximum button diameter in adaptive control welding. Finally, effects of each disturbance in combined field disturbances system with adaptive control had also been confirmed with the design of experiment (DOE) by minitab(R)16 for combined disturbances situation and suitability of optimum initial weld current had also established with real body part validation test.

Evaluation of reference genes for RT-qPCR study in abalone Haliotis discus hannai during heavy metal overload stress

  • Lee, Sang Yoon;Nam, Yoon Kwon
    • Fisheries and Aquatic Sciences
    • /
    • v.19 no.4
    • /
    • pp.21.1-21.11
    • /
    • 2016
  • Background: The evaluation of suitable reference genes as normalization controls is a prerequisite requirement for launching quantitative reverse transcription-PCR (RT-qPCR)-based expression study. In order to select the stable reference genes in abalone Haliotis discus hannai tissues (gill and hepatopancreas) under heavy metal exposure conditions (Cu, Zn, and Cd), 12 potential candidate housekeeping genes were subjected to expression stability based on the comprehensive ranking while integrating four different statistical algorithms (geNorm, NormFinder, BestKeeper, and ${\Delta}CT$ method). Results: Expression stability in the gill subset was determined as RPL7 > RPL8 > ACTB > RPL3 > PPIB > RPL7A > EF1A > RPL4 > GAPDH > RPL5 > UBE2 > B-TU. On the other hand, the ranking in the subset for hepatopancreas was RPL7 > RPL3 > RPL8 > ACTB > RPL4 > EF1A > RPL5 > RPL7A > B-TU > UBE2 > PPIB > GAPDH. The pairwise variation assessed by the geNorm program indicates that two reference genes could be sufficient for accurate normalization in both gill and hepatopancreas subsets. Overall, both gill and hepatopancreas subsets recommended ribosomal protein genes (particularly RPL7) as stable references, whereas traditional housekeepers such as ${\beta}-tubulin$ (B-TU) and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) genes were ranked as unstable genes. The validation of reference gene selection was confirmed with the quantitative assay of MT transcripts. Conclusions: The present analysis showed the importance of validating reference genes with multiple algorithmic approaches to select genes that are truly stable. Our results indicate that expression stability of a given reference gene could not always have consensus across tissue types. The data from this study could be a good guide for the future design of RT-qPCR studies with respect to metal regulation/detoxification and other related physiologies in this abalone species.

Temperature Calibration of a Specimen-heating Holder for Transmission Electron Microscopy

  • Kim, Tae-Hoon;Bae, Jee-Hwan;Lee, Jae-Wook;Shin, Keesam;Lee, Joon-Hwan;Kim, Mi-Yang;Yang, Cheol-Woong
    • Applied Microscopy
    • /
    • v.45 no.2
    • /
    • pp.95-100
    • /
    • 2015
  • The in-situ heating transmission electron microscopy experiment allows us to observe the time- and temperature-dependent dynamic processes in nanoscale materials by examining the same specimen. The temperature, which is a major experimental parameter, must be measured accurately during in-situ heating experiments. Therefore, calibrating the thermocouple readout of the heating holder prior to the experiment is essential. The calibration can be performed using reference materials whose phase-transformation (melting, oxidation, reduction, etc.) temperatures are well-established. In this study, the calibration experiment was performed with four reference materials, i.e., pure Sn, Al-95 wt%Zn eutectic alloy, NiO/carbon nanotube composite, and pure Al, and the calibration curve and formula were obtained. The thermocouple readout of the holder used in this study provided a reliable temperature value with a relative error of <4%.

A Source-Related Approach for Discussion on Using Radionuclide-Contaminated Materials in Post-accident Rehabilitation

  • Kazuji Miwa;Takeshi Iimoto
    • Journal of Radiation Protection and Research
    • /
    • v.48 no.2
    • /
    • pp.68-76
    • /
    • 2023
  • Background: In the process of discussion on the possibility of using radionuclide-contaminated soil and debris generated by radiation disasters, a strategy for the proper management of radiation exposure protection while considering the source of the contaminated materials is necessary. Materials and Methods: The radiological protection criteria that are likely to be applied to the source-related approach based on the International Commission on Radiological Protection recommendations and the International Atomic Energy Agency safety standards are summarized. We proposed five interpretations of radiation protection to contribute to the promotion of discussion on the possibility of using a part of low-level-radionuclide-contaminated soil and debris in the post-accident rehabilitation. Interpretations I to III are based on the idea of "using a reference level to protect the public in post-accident rehabilitation," whereas IV and V are based on the idea of "using the dose constraint to protect the public in the post-accident rehabilitation when the sources are handled in a planned activity." The former idea is subdivided into three based on the definition of the source, which is managed by the reference level, and the latter idea is divided into two depending on whether or not additional dose from using contaminated materials is deemed acceptable. Results and Discussion: To confirm the applicability of the five interpretations presented, we suggested the concrete values of protection criteria via two feasible cases. In this case study, we proposed radiation protection by the dose constraint based on the Interpretation IV and chose 1 mSv/yr for the public and 20 mSv/yr for workers dealing with radionuclide-contaminated materials. Conclusion: We concretely and systematically demonstrated how the concept of radiation protection can be applied to the process of discussion on the possibility of using radionuclide-contaminated materials within the framework of an international system of protection. This study's findings can provide necessary information to discuss the possibility of using radionuclide-contaminated materials as an alternative option for recovery and reconstruction after a radiation disaster from the viewpoint of radiation protection.

A comparative analysis of reference education between the United States and Korea (미국과 한국의 참고봉사 교육의 비교분석)

  • 정춘화
    • Journal of Korean Library and Information Science Society
    • /
    • v.23
    • /
    • pp.253-284
    • /
    • 1995
  • The purpose of this paper is to analyse the current status of reference education and to suggest directions for reference education in America and in Korea. For this purpose, the historical developments of reference services, and the names, problems and changes of reference courses are studied. The findings of the study can be summarized as follows; 1. The names of reference courses are various. In America, On-Line Services or Information Services are used in general, but in Korea, Reference Services are widely used. 2. In America, some library schools have only subject literature courses including business, law, music, etc. instead of basic reference courses. 3. Only one reference course is given by most schools in America and in Korea. However, a few schools which have no graduate courses provide two reference courses in Korea. 4. Analysis of textbooks used in reference courses shows that Reference Research by Joon-Shik Park, Reference Services and Reference Sources by Ock-Soon Noh are used in general. In addition, Introduction to Reference Work by Katz is used. 5. Lecture methods are generally used in teaching reference courses, but reviews of reference materials in library, class presentation, and case study method are also used. It is desirable that role playing and pathfinders' used in U.S. are introduced to our schools. 6. Analysis of library user instruction courses in Korea shows that 7 of 11 universities have the courses,, only one university teaches library user instruction as a part of reference courses, 3 universities don't. 7. Analysis of opinions about the directions for reference education shows that changes of reference courses names, expansion of courses contents, emphasis on communication technique, changes of teaching methods, proper combination of theory vs. practice, an increase in electronic reference education and training of subject specialist are needed.

  • PDF

Quantification of urea in serum by isotope dilution HPLC/MS (동위원소 희석 HPLC/MS에 의한 혈청 내 urea의 정량)

  • Lee, Hwashim;Park, Sangryoul
    • Analytical Science and Technology
    • /
    • v.18 no.4
    • /
    • pp.271-277
    • /
    • 2005
  • Urea in blood has been measured as an effective marker for diagnosis of renal function. Urea which is e end-product of nitrogen containing metabolites such as proteins is filtered through glomeruli of kidneys and then excreted as urine. If the renal function is deteriorated, the urea concentration in blood will be increased, from which the healthiness of renal function is judged. In order to improve the confidence of diagnosis results, the results must keep traceability chain to certified reference materials, which was certified by primary reference method. In this study, we proposed isotope dilution-liquid chromatography/mass spectrometry (ID-LC/MS) as a candidate primary method, in which $15^N_2$-urea is used as an internal reference material. The developed method is highly accurate in principle and is convenient as it does not require cumbersome derivatization. 0.1 mmol/L ammonium chloride was selected as a mobile phase for HPLC because it provided low interference in MS analysis of relatively low molecular weighted urea. HPLC and MS were connected with an electrospray ionization (ESI) interface of positive mode, which provided high sensitivity and reproducibility. The developed method was validated with internationally recognized reference materials, and we have obtained satisfactory results in an international ring trial. The expanded uncertainty calculated according to ISO guide was 1.8% at 95% confidence interval. The developed method is being used as a primary reference measurement method such as for certification of serum certified reference materials (CRMs).

Active Vibration Control of a Opened Box Structure By a Model Reference Neuro-Controller (모델기반 신경망 제어기를 이용한 열린 박스 구조물의 진동제어)

  • Jang, Seung-Ik;Shen, Yun-De;Kee, Chang-Doo
    • Proceedings of the KSME Conference
    • /
    • 2003.11a
    • /
    • pp.1602-1607
    • /
    • 2003
  • Vibration causes noise and sometimes makes structure unstable. Especially, due to the efforts of lightening, deformation of flexible structure is increased in its shape. Just a little disturbance can cause vibration and low damping ratio makes residual vibration last long time. This research is concerned with the model reference neuro-controller design for the vibration suppression of smart structures. By using a model reference neurocontroller, which is one of the algorithms of adaptive control, we performed an adaptive control of flexible cantilever plate and opened box structure with piezoelectric materials. The proposed adaptive vibration control algorithm, a model reference neuro-controller, was proved in its effectiveness by applying to an opened box structure. The model reference neuro-controller is implemented with DSP, and the real-time adaptive vibration control experiment results confirm that the model reference neuro-controller is reliable.

  • PDF

Development of certified reference material (CRM)s for surface analysis I : alloy thin film for surface compositional analysis (표면분석용 인증표준물질의 개발 I : 표면조성분석용 합금박막 표준물질)

  • 김경중;박용섭;문대원
    • Journal of the Korean Vacuum Society
    • /
    • v.8 no.3B
    • /
    • pp.276-282
    • /
    • 1999
  • For the quantitative surface analysis of multicomponent materials, algorithms for the compensation of the matrix effect and surface compositional change by ion beam sputtering must be established and reference materials having certified compositions are necessary. These certified reference material (CRM)s are needed for the improvement of instrument performance, inter-laboratory comparison and quantitative surface analysis. Surface analysis group of KRISS developed alloy thin film CRMs by and ion beam sputter deposition system and in-situ surface analysis system to control the composition of alloy thin films The real compositions of the CRMs were certified by inductively coupled plasma-atomic emission spectroscopy (ICP-AES).

  • PDF