• Title/Summary/Keyword: Inter-laboratory comparison

Search Result 39, Processing Time 0.023 seconds

Sea State Hindcast for the Korean Seas With a Spectral Wave Model and Validation with Buoy Observation During January 1997

  • Kumar, B. Prasad;Rao, A.D.;Kim, Tae-Hee;Nam, Jae-Cheol;Hong, Chang-Su;Pang, Ig-Chan
    • Journal of the Korean earth science society
    • /
    • v.24 no.1
    • /
    • pp.7-21
    • /
    • 2003
  • The state-of-art third generation wave prediction model WAM was applied to the Korean seas for a winter monsoon period of January 1997. The wind field used in the present study is the global NSCAT-ERS/NCEP blended winds, which was further interpolated using a bi-cubic spline interpolator to fine grid limited area shallow water regime surrounding the Korean seas. To evaluate and investigate the accuracy of WAM, the hindcasted wave heights are compared with observed data from two shallow water buoys off Chil-Bal and Duk-Juk. A detailed study has been carried with the various meteorological parameters in observed buoy data and its inter-dependency on model computed wave fields was also investigated. The RMS error between the observation and model computed wave heights results to 0.489 for Chil-Bal and 0.417 for Duk-Juk. A similar comparison between the observation and interpolated winds off Duk-Juk show RMS error of 2.28 which suggest a good estimate for wave modelling studies.

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

A Dynamic Offset and Delay Differential Assembly Method for OBS Network

  • Sui Zhicheng;Xiao Shilin;Zeng Qingji
    • Journal of Communications and Networks
    • /
    • v.8 no.2
    • /
    • pp.234-240
    • /
    • 2006
  • We study the dynamic burst assembly based on traffic prediction and offset and delay differentiation in optical burst switching network. To improve existing burst assembly mechanism and build an adaptive flexible optical burst switching network, an approach called quality of service (QoS) based adaptive dynamic assembly (QADA) is proposed in this paper. QADA method takes into account current arrival traffic in prediction time adequately and performs adaptive dynamic assembly in limited burst assembly time (BAT) range. By the simulation of burst length error, the QADA method is proved better than the existing method and can achieve the small enough predictive error for real scenarios. Then the different dynamic ranges of BAT for four traffic classes are introduced to make delay differentiation. According to the limitation of BAT range, the burst assembly is classified into one-dimension limit and two-dimension limit. We draw a comparison between one-dimension and two-dimension limit with different prediction time under QoS based offset time and find that the one-dimensional approach offers better network performance, while the two-dimensional approach provides strict inter-class differentiation. Furthermore, the final simulation results in our network condition show that QADA can execute adaptive flexible burst assembly with dynamic BAT and achieve a latency reduction, delay fairness, and offset time QoS guarantee for different traffic classes.

Exposure to low concentrations of mycotoxins triggers unique responses from the pig gut microbiome

  • Moon, Sung-Hyun;Koh, Sang-Eog;Oh, Yeonsu;Cho, Ho-Seong
    • Korean Journal of Veterinary Service
    • /
    • v.43 no.1
    • /
    • pp.39-44
    • /
    • 2020
  • The aim of this study is to investigate how the gut microbiome shifts when pigs were exposed with low concentrations of mycotoxins, deoxynivalenol (DON) and zearalenone (ZEN) in feed. Fifteen of pigs, 15 kg in weight which were negative for PRRSV and PCV2 were purchased, acclimatized until 20 kg in weight, and randomly divided into 3 groups; the DON group (DON treated), the ZEN group (ZEN treated) and the CTL (untreated negative control). DON and ZEN administered to each group for 30 days at 0.8 mg/kg (800 ppb) and 0.20 mg/kg (200 ppb) in feed, respectively. After extraction of microbial DNA from intestine and fecal samples, sequencing procedures were performed in the Ion PGM using an Ion 316 V2 chip and Ion PGM sequencing 400 kit. The results suggested that the bacterial communities in duodenum, jejunum and ileum of the DON and ZEN groups presented low-abundant OTUs compared with the CTL group. OTUs in cecum, colon and feces were determined more than in small intestine of all three groups. However, the CTL group yielded more OTUs than other two groups in inter-group comparison. It is not fully clarified how the richness and abundance in microbiome functions in the health condition of animals, however, the exposure to DON and ZEN has caused microbial population shifts representing microbial succession and changes following the diversity and abundance of porcine gut microbiome. The metabolomic analysis correlate with microbiome analysis is needed for further study.

Genetic characterization of microsporidians infecting Indian non-mulberry silkworms (Antheraea assamensis and Samia cynthia ricini) by using PCR based ISSR and RAPD markers assay

  • Hassan, Wazid;Nath, B. Surendra
    • International Journal of Industrial Entomology and Biomaterials
    • /
    • v.30 no.1
    • /
    • pp.6-16
    • /
    • 2015
  • This study established the genetic characterisation of 10 microsporidian isolates infecting non-mulberry silkworms (Antheraea assamensis and Samia cynthia ricini) collected from biogeographical forest locations in the State of Assam, India, using PCR-based markers assays: inter simple sequence repeat (ISSR) and random amplified polymorphic DNA (RAPD). A Nosema type species (NIK-1s_mys) was used as control for comparison. The shape of mature microsporidian spores were observed oval to elongated, measuring 3.80 to $4.90{\mu}m$ in length and 2.60 to $3.05{\mu}m$ in width. Fourteen ISSR primers generated reproducible profiles and yielded 178 fragments, of which 175 were polymorphic (98%), while 16 RAPD primers generated reproducible profiles with 198 amplified fragments displaying 95% of polymorphism. Estimation of genetic distance coefficients based on dice coefficients method and clustering with un-weighted pair group method using arithmetic average (UPGMA) analysis was done to unravel the genetic diversity of microsporidians infecting Indian muga and eri silkworm. The similarity coefficients varied from 0.385 to 0.941 in ISSR and 0.083 to 0.938 in RAPD data. UPGMA analysis generated dendrograms with two microsporidian groups, which appear to be different from each other. Based on Euclidean distance matrix method, 2-dimensional distribution also revealed considerable variability among different identified microsporidians. Clustering of these microsporidian isolates was in accordance with their host and biogeographic origin. Both techniques represent a useful and efficient tool for taxonomical grouping as well as for phylogenetic classification of different microsporidians in general and genotyping of these pathogens in particular.

Measurement of Soil CO2 Efflux Using a Closed Dynamic Chamber System (폐회로 역학 챔버 시스템을 이용한 토양 이산화탄소 플럭스 관측)

  • Chae, Nam-yi;Kim, Joon;Kim, Dong-gill;Lee, Do-won;Kim, Rae-Hyun;Ban, Ji-yeon;Son, Yo-whan
    • Korean Journal of Agricultural and Forest Meteorology
    • /
    • v.5 no.2
    • /
    • pp.94-100
    • /
    • 2003
  • Soil $CO_2$ emission is one of the primary components in carbon balance of terrestrial ecosystems. To accurately assess their net ecosystem exchange of $CO_2$ and net primary production, measurement of soil $CO_2$ efflux is required along with that of canopy $CO_2$ flux. In this paper, soil $CO_2$ flux measurement technique using closed dynamic chamber systems is briefly reviewed. Preliminary results on soil $CO_2$ exchange and inter-comparison of different measurement systems currently used in Korean regional network of tower flux measurement sites (KoFlux) are also reported.

Establishment of Test Conditions and Interlaboratory Comparison Study of Neuro-2a Assay for Saxitoxin Detection (Saxitoxin 검출을 위한 Neuro-2a 시험법 조건 확립 및 실험실 간 변동성 비교 연구)

  • Youngjin Kim;Jooree Seo;Jun Kim;Jeong-In Park;Jong Hee Kim;Hyun Park;Young-Seok Han;Youn-Jung Kim
    • Journal of Marine Life Science
    • /
    • v.9 no.1
    • /
    • pp.9-21
    • /
    • 2024
  • Paralytic shellfish poisoning (PSP) including Saxitoxin (STX) is caused by harmful algae, and poisoning occurs when the contaminated seafood is consumed. The mouse bioassay (MBA), a standard test method for detecting PSP, is being sanctioned in many countries due to its low detection limit and the animal concerns. An alternative to the MBA is the Neuro-2a cell-based assay. This study aimed to establish various test conditions for Neuro-2a assay, including cell density, culture conditions, and STX treatment conditions, to suit the domestic laboratory environment. As a result, the initial cell density was set to 40,000 cells/well and the incubation time to 24 hours. Additionally, the concentration of Ouabain and Veratridine (O/V) was set to 500/50 μM, at which most cells died. In this study, we identified eight concentrations of STX, ranging from 368 to 47,056 fg/μl, which produced an S-shaped dose-response curve when treated with O/V. Through inter-laboratory variability comparison of the Neuro-2a assay, we established five Quality Control Criteria to verify the appropriateness of the experiments and six Data Criteria (Top and Bottom OD, EC50, EC20, Hill slop, and R2 of graph) to determine the reliability of the experimental data. The Neuro-2a assay conducted under the established conditions showed an EC50 value of approximately 1,800~3,500 fg/μl. The intra- & inter-lab variability comparison results showed that the coefficients of variation (CVs) for the Quality Control and Data values ranged from 1.98% to 29.15%, confirming the reproducibility of the experiments. This study presented Quality Control Criteria and Data Criteria to assess the appropriateness of the experiments and confirmed the excellent repeatability and reproducibility of the Neuro-2a assay. To apply the Neuro-2a assay as an alternative method for detecting PSP in domestic seafood, it is essential to establish a toxin extraction method from seafood and toxin quantification methods, and perform correlation analysis with MBA and instrumental analysis methods.

Radiocarbon Analysis of water Using Direct $CO_2$ Absorption Method (이산화탄소 직접흡수법을 이용한 자연수의 방사성탄소동위원소분석)

  • 고용권;배대석;김천수;김성용
    • Journal of Soil and Groundwater Environment
    • /
    • v.6 no.2
    • /
    • pp.15-22
    • /
    • 2001
  • Radiocarbon ($^{14}C$) and tritium in water have been applied to hydrogeology as a tool for dating of groundwater. The long half-life of $^{14}C$(5,730 years) makes it useful for evaluation of residence time of groundwater, However, the $^{14}C$ has not been applied to groundwater studies in Korea, owing to the absence of preparation line for $^{14}C$ analysis. By this time $^{14}C$ of groundwater has been analyzed mainly using benzene synthesizer, which is so complicate and time-consuming that has been is limitedly applied to hydrogeology. Recently, the direct $CO_2$ absorption method for $^{14}C$ analysis was developed and introduced to KAERI for the evaluation of domestic groundwater system. The results of $^{14}C$ in groundwater would be usefully applied to hydrogeological studies such as the well understanding of groundwater flow system in depth. The reliability of our $^{14}C$ data was confirmed by inter-comparison with the qualified international isotope laboratory.

  • PDF

Quality Control on Neutron Activation Analysis for Urban Dust by the Proficiency Test (비교숙련도 시험을 통한 도시대기분진에 대한 중성자방사화분석법의 품질관리)

  • Moon, Jong-Hwa;Kim, Sun-Ha;Chung, Yong-Sam
    • Analytical Science and Technology
    • /
    • v.15 no.5
    • /
    • pp.433-438
    • /
    • 2002
  • Trace elements in two air filters (V-50, P-50) artificially loaded with urban dust provided from IAEA were determined non-destructively using instrumental neutron activation analysis. Standard reference material (Urban Particulate Matter, SRM 1648) of National Institute of Standard and Technology was used for analytical quality control. About 20 elements in both of loaded filter samples were determined. To evaluate inter-laboratory comparison and proficiency test, analytical data were statistically treated with the results which collected from 49 laboratories, 40 countries participated in this study using neutron activation analysis, particle induced X-ray emission, inductively coupled plasma mass spectroscopy, etc,. From the results of statistical treatment, Z-scores are within ${\pm}2$. Furthermore, accuracy and precision of obtained analytical values are passed according to the criteria of the proficiency test. Consequently, it was proved that analytical quality for air dust samples being performed has been controlled properly.

The Effect of Breathing Technique with Aerobic Exercise on the Respiratory Function of Adults (유산소 운동 시 호흡 기법에 따라 호흡 기능에 미치는 영향)

  • Ji-Won Han;Keon-Cheol Lee;In-Seob Kim
    • Journal of The Korean Society of Integrative Medicine
    • /
    • v.11 no.4
    • /
    • pp.135-145
    • /
    • 2023
  • Purpose : The purpose of this study was to discover which breathing technique is more effective in improving respiratory function by applying different breathing techniques-the chest expansion respiratory technique and the abdominal expansion respiratory technique-to adults in the same aerobic exercise situation. Methods : In this study, 30 people were randomly assigned to two groups: chest expansion respiratory technique with aerobic exercise (A group) and abdominal expansion respiratory technique with aerobic exercise (B group). Group A was asked to breathe after wrapping their rib cage with an elastic band, and Group B was asked to breathe after wrapping their abdomen with an elastic band. A total of 3 sets of 30 breaths were performed, 3 times a week for 6 weeks. For statistical processing, an independent t-test was used to verify homogeneity between the two groups, and a repeated measure analysis of variance (ANOVA) was used to compare differences according to the period for each group. Results : The changes in FVC and FEV1 for each group following 6 weeks of intervention are as follows. In comparison according to the intervention period, there was a significant increase in all groups depending on the timing of measurement (p<.05), and as a result of the inter-subject effect test, there was no significant difference between groups (p>.05). In addition, there was no interaction effect between period and group (p>.05). Conclusion : The conclusion of this study is that FVC and FEV1 values increased according to the intervention period in both groups; therefore, it can be suggested that flexible breathing techniques can be applied depending on the patient's physical situation when applying a breathing program to improve respiratory function.