• Title/Summary/Keyword: inter-laboratory study

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Evaluation of the Degradation of a 1300℃-class Gas Turbine Blade by a Coating Analysis (1300℃급 가스터빈 1단 블레이드의 코팅분석을 이용한 열화평가)

  • Song, Tae Hoon;Chang, Sung Yong;Kim, Beom Soo;Chang, Jung Chel
    • Korean Journal of Metals and Materials
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    • v.48 no.10
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    • pp.901-906
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    • 2010
  • The first stage blade of a gas turbine was operated under a severe environment which included both $1300^{\circ}C$ hot gas and thermal stress. To obtain high efficiency, a thermal barrier coating (TBC) and an internal cooling system were used to increase the firing temperature. The TBC consists of multi-layer coatings of a ceramic outer layer (top coating) and a metallic inner layer (bond coat) between the ceramic and the substrate. The top and bond coating layer respectively act as a thermal barrier against hot gas and a buffer against the thermal stress caused by the difference in the thermal expansion coefficient between the ceramic and the substrate. Particularly, the bondcoating layer improves the resistance against oxidation and corrosion. An inter-diffusion layer is generated between the bond coat and the substrate due to the exposure at a high temperature and the diffusion phenomenon. A thickness measurement result showed that the bond coat of the suction side was thicker than that of the pressure side. The thickest inter-diffusion zone was noted at SS1 (Suction Side point 1). A chemical composition analysis of the bond coat showed aluminum depletion around the inter-diffusion layer. In this study, we evaluated the properties of the bond coat and the degradation of the coating layer used on a $1300^{\circ}C$-class gas turbine blade. Moreover, the operation temperature of the blade was estimated using the Arrhenius equation and this was compared with the result of a thermal analysis.

An Empirical Study about the Impacts of Object-Oriented Diagrams On the Inter-Organizational Process Integration (객체지향 다이어그램을 이용한 기업간 프로세스의 통합에 관한 실증적 연구)

  • Nam, Jee-Won;Kim, Jin-Woo
    • Korean Management Science Review
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    • v.15 no.2
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    • pp.109-124
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    • 1998
  • Recently, as the importance placed on the design phase of system development has increased, the use of diagrams to design the overall system before implementing the actual program code has seen a proportionate increase. This study focuses on the diverse diagrams depicting organizational processes when integrating multiple processes of individual organizations to form an Inter-Organizational System(IOS). In this study, we attempt to identify the critical representation features of process diagrams that enable the effective integration of Inter-Organizational processes. In particular, the effect of the mapping relationship between the representation features of different diagrams to be integrated was tested empirically in a laboratory setting. The experimental task consisted of integrating the processes of two organization based upon the given process diagrams. Actual business processes were selected from real world cases and process diagrams were formulated based upon existing object-oriented notation. An analysis of the errors committed by the subjects during the integration process indicated that the mapping relationship between the diagram features representing the respective organizational processes had a significant impact upon the final integration outcome. Based upon these results, the present study provides a guideline for process diagrams that are crucial to effective Inter-Organizational process implementation and maintenance.

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A Study on Comparison Test of Disk Brake Lining for Rolling Stock (KRRI -CARS) (철도차량용 디스크 브레이크 라이닝의비교시험 연구)

  • Houg Yong-Ki;Kwon Sung-Tae;Chung Jong-Duk;Kim Jung-Nam
    • Proceedings of the KSR Conference
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    • 2004.10a
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    • pp.483-488
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    • 2004
  • The inter-laboratory comparison test which is demanded on the authorized test of ISO/IEC 17025 is the program to guarantee the confidence of test result. This paper, as a part of the inter-laboratory comparison test between South Korea and China, is refered to the characteristic of friction coefficient of disk brake lining for rolling stock according to disk type. Brake tests were carried out under constant brake force and operating sequence by using dynamo-tester according to disk and disk lining types. To establishing the confidence of test result, we calculated A type uncertainty about friction coefficient and investigated the factors about the variation of friction coefficient.

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Determiniation and Validation of Alibendol using High Pressure Liquid Chromatography in Human plasma (고속액체크로마토그라피법을 이용한 사람 혈장 중 알리벤돌(Alibendol)의 정량 및 검증)

  • Song, Hyun-Ho;Yu, Ji-Young;Kim, Bo-Gyeom;Park, Hyeon-Ju;Choi, Kwang-Sik;Kwon, Young-Ee
    • YAKHAK HOEJI
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    • v.54 no.4
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    • pp.295-299
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    • 2010
  • The aim of this study was to develop and validate for determination of alibendol in human plasma by HPLC method. After precipitation of 500 ${\mu}l$ plasma samples by 50% methanol 50 ${\mu}l$ and 60% perchloric acid 30 ${\mu}l$ and the supernatant 50 ${\mu}l$ was injected into HPLC. The assay was performed isocratically using 10 mM potassium phosphate (pH 3.0) and acetonitrile (80 : 20, v/v) as mobile phase. The $C_{18}$ column (particle size $3.5{\mu}m$, $4.6{\times}50$ mm, Zorbax Eclipse) was used as a solid phase. The mobile phase was delivered at a flow-rate of 1.7 ml/min, detection was by ultraviolet absorption at 232 nm and concentrations were calculated on the basis of peak areas. In these conditions, alibendol can be separated from ethylparaben, the internal standard, and endogenous substances. The retention times of alibendol and ethylparaben were just about 2.6 and 3.5 minutes, respectively. This rapid HPLC method was validated by examining the precision and accuracy for inter- and intra-day analysis. The standard curve was linear ($R^2$=1.0000) over the concentration range of 0.05~20 ${\mu}g$/ml. The inter-day relative standard deviation (R.S.D.) and accuracy were 0.2~12.2% and 94.4~101.2% (82.7% at the lower limit of quatitation). The intra-day R.S.D. and accuracy were 0.1~11.8% and 98.8~102.5%, respectively. The method was successfully applied to the determination of alibendol in plasma for a pharmacokinetic study.

Effects of inter-implant distance on the accuracy of intraoral scanner: An in vitro study

  • Thanasrisuebwong, Prakan;Kulchotirat, Tharathip;Anunmana, Chuchai
    • The Journal of Advanced Prosthodontics
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    • v.13 no.2
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    • pp.107-116
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    • 2021
  • PURPOSE. Several studies focused on the accuracy of intra-oral scanners in implant dentistry, but the data of inter-implant distances were not widely mentioned. Therefore, this study aimed to evaluate the effect of distance between two implants on the surface distortion of scanned models generated by intra-oral scanners. MATERIALS AND METHODS. Three models with the distances between two fixed scan bodies of 7, 14, and 21 mm were fabricated and scanned with a highly precise D900L dental laboratory scanner as reference models. Fifteen scans were performed with TRIOS3 and CEREC Omnicam intra-oral scanners. Trueness, precision, and angle deviation of the test models were analyzed (α=.05). RESULTS. There was a significant difference among inter-implant distances in both intraoral scanners (P<.001). The error of trueness and precision increased with the increasing inter-implant length, while the angle deviation did not show the same trend. A significant difference in the angle deviation was found among the inter-implant distance. The greatest angle deviation was reported in the 14-mm group of both scanners (P<.05). In contrast, the lowest angle deviation in the 21-mm group of the TR scanner and the 7-mm of the CR scanner was reported (P<.001). CONCLUSION. The inter-implant distance affected the accuracy of intra-oral scanner. The error of trueness and precision increased along with the increasing distance between two implants. However, the distortions were not clinically significant. Regarding angle deviation, the clinically significant angle deviation may be possible when using intra-oral scanners in the partially edentulous arch.

Preparation of a CRM for QA/QC in dioxin analysis and inter-laboratory study (다이옥신 정도 관리용 CRM 제조와 실험실간 비교평가)

  • Yu, Byeong-Woon;Moon, Young-Hoon;Kim, Min-Kwan;Kyoung, Jong-Dai;Chang, Yoon-Seok
    • Analytical Science and Technology
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    • v.17 no.2
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    • pp.153-162
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    • 2004
  • Dioxin CRM for QA/QC was prepared with fly ash collected from municipal waste incinerator. With that CRM inter-laboratory test was carried out. The collected fly ash was conducted several homogeneity steps including sievings and mixing. Homogeneity test and estimation of uncertainty was performed by one-way ANOVA based on ISO guide 35. Compared concentrations of fly ash of participants to CRM values, PCDDs value was lower than that of CRM in almost participants, and showed higher PCDFs concentration than that of CRM. Although there is a small difference in PCDD/Fs concentrations with congeners of extract, the result was close to mean value.

The effects of Inter-professional Patient Safety Education in clinical practice for healthcare college students (보건의료계열 대학생 대상 전문직 간 환자안전 교육프로그램이 임상실습에 미치는 효과)

  • Shin, Eunhee
    • Journal of Digital Convergence
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    • v.17 no.11
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    • pp.409-417
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    • 2019
  • This study was done to identify the effects of the inter-professional education program on the knowledge, attitude, and self-confidence of patient safety in the clinical practice of nursing, physical therapy and biomedical laboratory students. Each week for 6 weeks, a lecture and group discussion were given to twenty-nine students. Data were collected by self-administered questionnaire and interview. The knowledge and self-confidence were increased but the attitude was not changed. Students showed the increased their awareness of patient safety and the importance of collaboration with other occupational groups. It is necessary to establish a inter-professional education program between departments to enhance the ability to work collaboratively based on good communication along with knowledge, attitude in clinical settings.

Minimization of Energy Consumption for Amine Based CO2 Capture Process by Process Modification

  • Sultan, Haider;Bhatti, Umair H.;Cho, Jin Soo;Park, Sung Youl;Baek, Il Hyun;Nam, Sungchan
    • Journal of Energy Engineering
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    • v.28 no.4
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    • pp.13-18
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    • 2019
  • The high energy penalty in amine-based post-combustion CO2 capture process is hampering its industrial scale application. An advanced process is designed by intensive heat integration within the conventional process to reduce the stripper duty. The study presents the technical feasibility for stripper duty reduction by intensive heat integration in CO2 capture process. A rigorous rate-based model has been used in Aspen Plus® to simulate conventional and advanced process for a 300 MW coal-based power plant. Several design and operational parameters like split ratio, stripper inter-heater location and flowrate were studied to find the optimum values. The results show that advanced configuration with heat integration can reduces the stripper heat by 14%.

Epidemiological Studies of Avian Paramyxovirus Type 4 and 6 in Commercial Chicken Flocks in Korea

  • Lee, Hae Rim;Koo, Bon-Sang;Jeon, Eun-Ok;Han, Moo-Sung;Min, Kyung-Cheol;Lee, Seung Baek;Bae, Yeonji;Choi, Kang-Seuk;Shin, Jeong-Hwa;Mo, In-Pil
    • Korean Journal of Poultry Science
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    • v.40 no.4
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    • pp.379-388
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    • 2013
  • Avian paramyxovirus (APMV) type 4 and 6 were isolated during an avian influenza (AI) surveillance program of wild birds. This study also conducted experimental infection of wild-bird-origin APMV type 4 and 6 in specific pathogen free (SPF) chickens to study pathogenicity and transmission within domestic flocks. In addition, serological prevalence data of APMV type 4 and 6 in domestic fowls was conducted with chicken sera collected from 2007 to 2009 in order to understand infection status. The results of the animal experiment showed that APMV type 4 and 6 had the ability to infect chickens with sero-conversion and to transmit the virus from infected birds to contacted birds, but showed low pathogenicity. Serological tests revealed that APMV type 4 was widespread in the poultry industry, especially in layer flocks, but the positive rate for APMV type 6 was very low. This study concluded that wild bird-origin APMV type 4 and 6 could infect the chickens by inter-species transmission and the seroprevalence of APMV type 4 was quite high in Korean poultry. However, since almost all the chicken flocks had a high level of antibody titer against APMV type 1, there was possibility of cross reaction between APMV type 1 and 4, which made the interpretations more complicated. In order to understand infection status in the natural environment, additional study is necessary regarding the seroprevalence of APMV type 4 and 6 in the wild bird population.

An Analysis of Laboratory Instructions in Elementary School Science (초등학교 과학 실험 수업 분석)

  • Yang, Il-Ho;Jeong, Jin-Woo;Hur, Myung;Kim, Young-Shin;Kim, Jin-Soo;Cho, Hyun-Jun;Oh, Chang-Ho
    • Journal of Korean Elementary Science Education
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    • v.25 no.3
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    • pp.281-295
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    • 2006
  • The purpose of this study was to analyze laboratory instructions used in elementary school science lessons by utilizing an analysis instrument for science laboratory instruction(AISLI). This analysis instrument was comprised of 3 elements; the aim of the laboratory activity, the interaction generated, and the inquiry process. There were also a total of 20 sub-categories and its validity was identified at 0.89 by four science educators. For the purposes of this study, 90 laboratory instructions were video-recorded, then transcribed. Laboratory instructions were analyzed by three analyst teams, and the inter-rater reliability within teams was checked through Pearson correlation, with a score of 0.91. The results of this study were as follows: the two principle aims of laboratory activity, namely, to acquire declarative knowledge and to increase attitudes toward science, were observed to be in evidence in 98.9% and 92.2% in laboratory instructions, and the levels of categories of the interaction and inquiry processes were situated at level-1. The implications of these results are that laboratory instructions currently in use do not place sufficient demands upon students' scientific thinking and are not at all conducive to student-centered activities. Therefore in order to remedy this situation, the usefulness of current science laboratory instructions need to be re-evaluated.

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