• Title/Summary/Keyword: Standard reference material

Search Result 239, Processing Time 0.031 seconds

A Study on the Development Type of Component Joint Design for Environment Friendly Multi Housing Remodeling (공동주택의 친환경 리모델링을 위한 부품접합부 개선방안의 유형화에 관한 연구 II;욕실 및 주방을 중심으로)

  • Lim, Seok-Ho;Kim, Soo-Am;Hwang, Eun-Kyoung;Yun, Mae-Han
    • Proceeding of Spring/Autumn Annual Conference of KHA
    • /
    • 2006.11a
    • /
    • pp.370-373
    • /
    • 2006
  • Lastly, the problem of filling occurs in the process of concealed joint of adjacent components and was seen in joints between the structure and an electrical or mechanical device. Therefore, the dry processing which replaces wet joint was seen in joints between the structure and a door, ones between the structure and a finishing materials, ones between a gypsum board and electrical device, and ones between a water pipe and a tile finishing. And a process of separating the area of jointed parts in order to eliminate the problem of overlap was seen in joints between a door and a finishing material and ones between a gypsum board on the ceiling and a light. Lastly, an analysis of a process of exposing concealed parts indicated that the problem of filling could be applied to joints between the structure and an electrical or mechanical device and ones between a finishing material and a mechanical device. This study sought out methods to apply Environment Friendly Multi Housing Remodeling that allow easy remodeling as part of environment- preserving policies. It also contains basic data useful to implement long-life houses in the future by presenting a comprehensive design standard for them

  • PDF

Prediction of Air Movement and Temperature Distribution at Different Store Methods Using 3-D CFD Simulation in Forced-Air Cooling Facility

  • Yang, G.M.;Koh, H.K.
    • Agricultural and Biosystems Engineering
    • /
    • v.3 no.2
    • /
    • pp.65-72
    • /
    • 2002
  • Temperature is the most influential environment parameter which affects the quality change of agricultural products in cold storage. Therefore, it is essential to keep the uniform temperature distribution in the storage room. This study was performed to analyze the air movement and temperature distribution in the forced recirculating cold storage facility and to simulate optimum storage method of green groceries using 3-D CFD(three dimensional computational fluid dynamics) computer simulation which applied the standard $textsc{k}$-$\varepsilon$ turbulence model and FVM(finite volume method). The simulation was validated by the experimental results for onion storage and the simulation model was used to simulate the temperature and velocity distribution in the storage room with reference to the change of storage method such as location of storage, no stores, bulk storage, and pallet storage. In case of no stores, internal airflow was circulated without stagnation and consequently air movement and temperature distribution were uniform. In case of bulk storage, air movement was stagnated so much and temperature distribution of onion was not uniform. Furthermore, the inner temperature of onion roses more than the initial temperature of storage. In case of pallet storage, air movement and temperature distribution of onion were so uniform that the danger of quality change was decreased.

  • PDF

STUDIES ON THE FRAGILITY OF TOBACCO RAW MATERIAL (잎담배의 부스러짐 특성에 관한 연구)

  • 김기환;유광근;주영석;최영현;김병구
    • Journal of the Korean Society of Tobacco Science
    • /
    • v.8 no.1
    • /
    • pp.13-21
    • /
    • 1986
  • The fragility, which express the fineness index, increased linearly with the moisture content for various tobacco shreds and showed a high correlation to the moisture content. Then, fineness index (FIs) at reference moisture content(l2.5%) was obtained by following equation. FIs=FIm+A(12.5-Mm) A" denote the gradient of simple linear regression equation between the fineness index and moisture content. FIm; the fineness index measured at the standard moisture content(12.5%). The characteristics of fragility concerning with some kinds of tobacco raw materials, stalk position, moisture content and storaged time were investigated. The following results were obtained. 1. The moisture content range of less fragile of tobacco raw material was from 16% to 20%. whereas the rolled process sheet tobacco was from 12% to 16%. 2. The Bright yellow and the paper process sheet tobacco were less fragile than that of the other tobacco raw materials. 3. The leaves were more distant from middle stalk position, and its become more fragile. 4. Physical properties of the storaged tobacco leaves were determined as a function of each storageunction of each storage time. The long-term storaged leaves(more than 3 years) were slightly lighter weight, more fragility and lower equilbrium moisture content than thos of the mid-term storaged leaves.(less than 3 years). 5. Contents of chemical component of the storaged leaves were determined every storage time. The long-term storaged leaves were slightly lower content of nicotine and chlorine than those of mid-term storaged leaves, but contents of crude fiber, total ash and calcium were increased significantly.

  • PDF

3D reconstruction of two-phase random heterogeneous material from 2D sections: An approach via genetic algorithms

  • Pizzocri, D.;Genoni, R.;Antonello, F.;Barani, T.;Cappia, F.
    • Nuclear Engineering and Technology
    • /
    • v.53 no.9
    • /
    • pp.2968-2976
    • /
    • 2021
  • This paper introduces a method to reconstruct the three-dimensional (3D) microstructure of two-phase materials, e.g., porous materials such as highly irradiated nuclear fuel, from two-dimensional (2D) sections via a multi-objective optimization genetic algorithm. The optimization is based on the comparison between the reference and reconstructed 2D sections on specific target properties, i.e., 2D pore number, and mean value and standard deviation of the pore-size distribution. This represents a multi-objective fitness function subject to weaker hypotheses compared to state-of-the-art methods based on n-points correlations, allowing for a broader range of application. The effectiveness of the proposed method is demonstrated on synthetic data and compared with state-of-the-art methods adopting a fitness based on 2D correlations. The method here developed can be used as a cost-effective tool to reconstruct the pore structure in highly irradiated materials using 2D experimental data.

Lead isotope measurement of geological reference materials using thermal ionization mass spectrometry (열이온화질량분석기를 이용한 암석표준시료에 대한 납 동위원소 분석)

  • Lee, Hyo Min;Jo, Hui Je;Kim, Taehoon
    • Analytical Science and Technology
    • /
    • v.33 no.6
    • /
    • pp.245-251
    • /
    • 2020
  • Lead (Pb) has been shown to be a useful tracer of contamination sources and geochemical processes such as age dating and crustal evolution. These studies require a chromatographic technique for Pb separation from geological samples. This paper presents a comparison study on the effect of eluent concentration between 6M HCl and 8M HCl on the separation of Pb from Pb resin. The results showed that the separation of Pb using 6M HCl as the eluent was not effective compared to the separation using 8M HCl. To verify this method, we measured the Pb isotopic compositions of the Pb isotopic standard (NIST NBS981) and geological reference materials (BCR-2, GSP-2, and JG-1a) using a thermal ionization mass spectrometer (TIMS). The results correspond well with the reported values within the error range, implying that this method can be useful.

Evaluation of analytical methods for several metals and fluoride by certified reference materials (인증표준물질을 이용한 중금속류와 플루오르화물 전처리방법 비교 연구)

  • Jeon, Tae Wan;Chung, David;Shin, Sun Kyoung;Choi, Hun Geun;Chung, Young Hee
    • Analytical Science and Technology
    • /
    • v.19 no.2
    • /
    • pp.172-180
    • /
    • 2006
  • This study was performed to establish new methods for hazardous substances and to develop an analytical method in specified wastes for preventing the environmental pollution caused by hazardous wastes. Therefore, the trends of international management, regulatory criteria, and items of hazardous wastes in various countries were investigated. Based on this study, target priority of new hazardous substances in specified wastes was established. An analytical method was developed using the waste standard reference materials of sludge, oil, bottom ash, etc., which contain the new hazardous substances (Ba, Be, Cr(VI), F, Ni, Sb, Se, and V). A total of 37 waste samples from the representative facilities, which are emitting new hazardous substances, were analyzed.

Evaluation of proficiency and improvement of accuracy on the analysis of brominated flame retardants (PBDEs) in ABS polymer (ABS수지 중 polybrominated diphenyl ether(PBDE)류 분석 숙련도 평가 및 정확도 향상)

  • Ryu, Jehoon;Kim, Dalho
    • Analytical Science and Technology
    • /
    • v.28 no.6
    • /
    • pp.446-452
    • /
    • 2015
  • In order to evaluate and improve the ability of Korean testing laboratories to measure Polybrominated diphenyl ethers in acrylonitrile-butadiene-styrene (ABS), a proficiency test was organised by Korea Research Institute of Standards and Science (KRISS) based on ISO/IEC 17043. The proficiency test material used was 10 g of a granular ABS fortified with a mixture of congeners of PBDE (BDE-154, 183, 206, 209). Homogeneity and stability were investigated to assess the adequacy of the test material. The certified value established by KRISS based on the national reference was used for assigned value of each PBDE. The test materials were distributed to the 16 participating laboratories. The participating laboratories were requested to analyse the samples employing the methods used in their routine analysis. Each laboratory was given it’s own code to secure the anonymity. Participants results were evaluated with z-scores according to ISO/IEC 17043. The standard deviation for proficiency assessment was set by standard deviation of the participants results except for outlier. The results, the laboratory's performance and improvement of accuracy were discussed.

Analysis of Butyltin Compounds(mono-, di-, and tributyltin) in Human Blood (혈액 중의 주석화합물(MBT, DBT, TBT)의 분석과 농도에 관한 연구)

  • Kim, Nam Sook;Park, Dong Uk;Oh, Jae Ryoung;Shim, Woon Joon
    • Analytical Science and Technology
    • /
    • v.14 no.2
    • /
    • pp.115-122
    • /
    • 2001
  • Butyltin compounds, including mono-(MBT), di-(DBT) and tributyltin(TBT) were analyzed in 44 human blood samples randomly collected from a hospital in "K" a city. Gas chromatograph equipped with flame photometric detector(FPD) was used to quantify the amounts of butylin compounds. Method detection limits(MDL) of this analytical method were 3.69ng Sn/g for MBT, 0.91ng Sn/g for DBT and 1.09ng Sn/g wet wt for TBT respectively. Standard reference material(SRM) containing of $1.3{\mu}g/g$ TBT as chloride was analyzed to check if this analytical results would be reliable. Recovery of about 90% was obtained through this analysis, indicating that the analytical method from butyltin compounds blood was reliable. The concentrations of butyltin compounds ranged MDL(<3.69) to 7.93ng Sn/g for MBT and 1.15 to 5.41ng Sn/g wet wt for DBT. Tributyltin was below detection limit in all samples. Detection limits of our results are lower than those reported by Kannan et al. who reported butyltin compounds in 33 human blood samples in the United States. Detection of MBT and DBT on blood sample implies that butyltin compounds could be absorbed through consumption of seafoods or exposure to food stuffs made of plastics and household items. Further study is needed to examine if butyltin compounds in blood can be reliably analyzed and used as intake index.

  • PDF

Effect of Zircon on Rare-Earth Element Determination of Granitoids by ICP-MS (ICP-MS를 이용한 화강암내 희토류원소 분석시 저어콘이 미치는 영향)

  • Lee, Seung-Gu;Kim, Taehoon;Han, Seunghee;Kim, Hyeon Cheol;Lee, Hyo Min;Tanaka, Tsuyoshi;Lee, Seung Ryeol;Lee, Jong Ik
    • The Journal of the Petrological Society of Korea
    • /
    • v.23 no.4
    • /
    • pp.337-349
    • /
    • 2014
  • We measured rare earth element and Zr concentrations of USGS granite standard material GSP-2 and GSJ granite standard material JG-1a to clarify the effect of zircon during rare earth element analysis using ICP-MS. We also measured rare-earth element and zirconium (Zr) contents of zircon from granite by acid-digestion methods using conventional teflon vial and pressure-bomb. The results show that acid-digestion using teflon vial dissolved ca. 50% of zircon compared to pressure-bomb method. The Zr contents of JG-1a and GSP-2 gave ca 50% of reference value. However, rare-earth element abundance of JG-1a and GSP-2 were similar to those of reference values. This suggests that the decomposition degree of zircon might give a negligible effect on a petrological and geochemical interpretation using chondritenormalized REE pattern.

A Study on Improvement and Change Properties of Landscape Construction Standard Specification - Focused on Planting - (조경공사 표준시방서 변화특성과 개선방향 연구 - 식재공사를 중심으로 -)

  • Yu, Joo-Eun;Jun, Jin-Wan;Lee, Sang-Suk
    • Journal of the Korean Institute of Landscape Architecture
    • /
    • v.41 no.1
    • /
    • pp.60-70
    • /
    • 2013
  • This study focused on analyzing classification system, technique methods, quality levels of periodic amendment characteristics in planting of standard specification. Through analyzing the above and comparing with foreign case study, this study suggests the improvement directions. The results improvement directions are as follows. 1. Many kinds of new construction were set up through the amendments of Landscape Standard Specification, but there are still needs to combine some construction categories because of mismatches between upper and lower categories. 2. Although the Landscape Standard Specification was revised to be more concrete, the contents there remains an ambiguous expression. So, standard specification is needed to revise a depth of earth ball or strength of support materials and quantify collect period of topsoil and application time. In addition, standards about following supervisor's instruction should be more detailed or deleted. 3. The standard specification has not been specified despite enactment and amendments reflecting the periodical paradigm and the needs of users, so it is still needed to revise. In addition, quality levels, planting periods, size of earth ball and performance criteria of tree materials are needed to revise. Each specific classification and construction methods were made by amendments of standard specification, but some standards are not clear and concrete. Therefore, the standard specification is needed to revise the classification system, technique methods, and problem deduction of quality levels and proposal of improvement. This study will be reference material when Landscape Standard Specification is revised.