• Title/Summary/Keyword: SEM evaluation

Search Result 950, Processing Time 0.027 seconds

Development of a Ride-comfort Model for Korea Train eXpress (KTX) Passengers (한국형 고속철도 승차감의 감성 모형 개발)

  • Lee, Joo-Hwan;Lee, Cheol;Kim, In-Ki;Yun, Myung-Hwan
    • Journal of the Ergonomics Society of Korea
    • /
    • v.26 no.1
    • /
    • pp.87-92
    • /
    • 2007
  • KTX (Korea Train eXpress) is launched as the $5^{th}$ develop a ride-comfort model for high-speed rail pasengers using structural equation model (SEM). Both qualitative and quantitative factors affecting ride-comfort were investigated, and employed to construct a comprehensive ride-comfort model. The SEM model was built with twenty measurement variables and seven latent variables for the evaluation of ride-comfort of high-speed train passenger. A total of six hundreds thirty two subjects participated in the evaluation using face-to-face survey method. As a result, the proposed SEM model model fitnes (GFI=0.93). According to the results, overall ride-comfort was significantly affected by the seat-, fatigue-, interior-related, and customer satisfaction variables such as fare. Among the engineering design variables of high-speed train, seat-related variables were identified as critical factors of the ride-comfort. It is expected that the result of this study could be useful for the enhancement of ride comfort in next generation KTX.

Evaluation of Microscopic Wear Characteristics for CVD TiN Coatings with SEM Tribosystem (SEM Tribosystem에 의한 CVD TiN막의 미시적 마모 특성 평가)

  • 문봉호
    • Journal of the Korean institute of surface engineering
    • /
    • v.37 no.3
    • /
    • pp.137-145
    • /
    • 2004
  • This study surveys the microscopic wear of CVD TiN coatings in repeated sliding, using the SEM Tribosystem as in-situ system. According to the research, the depth of wear groove and the specific wear amount are changed by the transition of the microscopic wear mode. This investigation leads to the fact that the change of wear characteristics produces the transition of the wear mode. In this survey, four modes are observed for CVD TiN coatings with the thickness of 1.6$\mu\textrm{m}$: ploughing, powder formation, flake formation and coating delimitation. The microscopic wear properties is quantitatively evaluated in terms with the microscopic wear mode and the specific wear amount. These relationships prove that the observation of wear modes with a SEM Tribosystem is useful to evaluate wear properties.

A Systemic Model for the Gifted Education (체제적인 영재교육을 위한 Renzulli의 전교 심화학습 모형(SEM)의 개성방안)

  • Park, Eun-Young
    • Journal of Gifted/Talented Education
    • /
    • v.10 no.2
    • /
    • pp.1-23
    • /
    • 2000
  • The Schoolwide Enrichment Model(SEM) is a representative model for the gifted education. As the model seems to be more conceptual in nature, it is hard to respond to the different interests and changing needs of the gifted learners. Also it does not provide specific procedures and prescriptions in teaching-learning processes for the teachers. Therefore, SEM needs to be modified into a Systemic Model that is more flexible and procedural. The paper proposes an Instructional Systems Design(ISD) model for SEM. The Systemic Model for SEM consists of 5 major steps. These are as follows: Planning, Diagnosis, Prescription, Implementation, Evaluation. In Planning step, there is a six-stage procedure for initiating the implementation of the SEM. In Diagnosis step, there are two-phases in identifying students for participation in the SEM and assessing strengths, interests, and talents of the learners and recording in The Total Talent Portfolio(TTP). In Prescription step, Curriculum Compacting is administered as a systematic procedure for modifying thecurriculum for above-average ability students. In Implementation step, Enrichment Learning and Teaching is an instructional strategy designed to promote active engagement in learning for teachers and students. Whenever each step has completed, Evaluation step should be followed. These 5 steps are repetitive, cycling and interactive. That is, each one becomes input for the next step, process for itself, and output for the previous step. Each step is monitored through the process of Review and Revision step. In conclusion, the paper suggests six strengths of the Systemic Model for SEM; The Model (1) provides the specific procedure in teaching-learning process; 92) has interactive relations with each component; (3) can be revised continuously for creation of the most effective system; (4) can be implemented more flexibly; (5) can be developed as an unique system for each school; (6) facilitates communications between teachers and students.

  • PDF

Skin Improvement Effect of Mask Pack with Snail Fermented Extract (달팽이 발효 추출물을 이용한 마스크 팩의 피부개선효과)

  • Zhoh, Choon-Koo;Lee, Min-Hee;Kim, In-Young;Shin, Ji-Young
    • Journal of the Korean Applied Science and Technology
    • /
    • v.33 no.1
    • /
    • pp.30-40
    • /
    • 2016
  • This study related to get skin improvement effect of sheet mask pack using 5% of $2^{nd}$ fermented snail extract. To the scientific study of the skin, it was used for this sheet mask of 100% cotton as cutting face shape. We reported the results of measurement of skin improvement effect with the placebo and Gene-SEM (general snail extract mask). First; moisturizing effect of 2F-SEM ($2^{nd}$ fermented snail extract mask) has been increased about 11% than the PM and Gene-SEM was improved about 4.7% more than the PM (placebo mask). Second; elasticity of the mask pack containing $2^{nd}$ fermented snail extract was 13.8% better than PM and Gene-SEM was improved about 6.7 % more than PM. Third; Skin roughness of 2F-SEM has improved 6.80% than PM and Gene-SEM was improved about 2.3% more than PM. Fourth; melanin reductive effect of 2F-SEM was improved about15.0% more than PM and Gene-SEM was improved about 8.7% more than PM. Fifth; fine wrinkle decline effect of 2F-SEM was about 8.0% better than PM and Gene-SEM was improved with 5.1% more than PM. Sixth; sensorial evaluation of 2F-SEM using $2^{nd}$ fermented snail extract was significantly showed difference merits regarding softness, moisture, fine-wrinkle improvement.

Carbon Nano Tube Dispersion Evaluation in B-stage Resin Films (B-stage 레진 필름의 카본나노튜브 분산도 평가 및 제조공정 최적화)

  • Oh, Young-Seok;Park, Tea-Hoon;Byun, Joon-Hyung;Yi, Jin-Woo;Kim, Byung-Sun;Joe, Chee-Ryong
    • Composites Research
    • /
    • v.29 no.6
    • /
    • pp.353-357
    • /
    • 2016
  • An appropriate way to fabricate a hybrid composite containing evenly dispersed carbon nano tubes(CNTs) is to stacking B-stage resin films that contain evenly dispersed CNTs and various reinforcing fiber layers alternatively. In the present study, B-stage resin films are manufactured via shear mixing and three-roll milling. CNT dispersion in resin via these two processes are evaluated by SEM on their fracture surfaces. For more efficient process, the dispersivities are evaluated according to the number of calendering passes. Samples are made for different number of passes during calendering, and their dispersions are evaluated via SEM fractographs as well as by measuring their electrical conductivities. Additionally, the optimal process conditions are obtained by measuring the electrical conductivity and evaluating their dispersivity of the samples prepared by gap mode and force mode.

Cleanliness Test by Spray-Type Cleaning Agent for Electronic and Semiconductor Equipment (전자·반도체용 스프레이 분사형 세정제에 대한 청정도 평가)

  • Heo, Hyo Jung;Row, Kyung Ho
    • Korean Chemical Engineering Research
    • /
    • v.47 no.6
    • /
    • pp.688-694
    • /
    • 2009
  • A spray-type cleaning agent in utilizing dust-remover on PCB was chosen to study the cleanliness test and efficiency. In order to choose alternative environmental-friendly cleaning agents, it is important that the systematic selection procedures should be introduced and applied through the evaluation of their cleaning ability, environmental characteristics, and economical factors, and that the objective and effective evaluation methods of cleanliness should be established for the industry. A novel cleaning evaluation method with scanning electron microscopy/energy-dispersive X-ray analysis of surface observation evaluation method and an infra-red thermography camera(THERMOVISION A20 model) was studied in this work. The sound card(CT-2770 model) cut by $2{\times}2cm$ size was used as a part, and before and after the spray cleaning, the cleanliness was observed by the image analyzer of SEM and further the removal efficiency of dust was quantitatively evaluated by the component analysis of EDX. For the parts of P4TE model motherboard and IPC-A-36 PCB plate, before and after the spray cleaning, temperature differences were measured and compared at room temperature and 50 oven temperature by an infra-red thermography camera in the contaminants of dust and iron powder.

Physico-chemical characterization of individual particles emitted from the air pollution point sources (대기 점오염원에서 배출되는 개별입자상물질의 물리화학적 특성)

  • Park Jeong-Ho;Suh Jeong-Min
    • Journal of Environmental Science International
    • /
    • v.14 no.8
    • /
    • pp.761-770
    • /
    • 2005
  • Scanning electron microscopy / energy dispersive X-ray analyzer(SEM/EDX) has played an important role for evaluation the source of atmospheric particle because it is a powerful tool for characterizing individual particles. The SEM/EDX system provides various physical parameters like optical diameter, as well as chemical information for a particle-by-particle basis. The purpose of the study was to classify individual particle emitted from the point sources based on clustering analysis and physico-chemical analysis by SEM/EDX. The total of 490 individual particle were analyzed at 8 point sources including coal-fired power plant, incinerator, H-C oil boiler, and metal manufacturing industry. The main components were Si and AI in the coal-fired power plant, Cl and Na in the domestic waste Incinerator, S in the H-C oil boiler and S and Fe in the metal manufactory industry, respectively.

Isotopic Analysis of NUSIMEP-6 Uranium Particles using SEM-TIMS

  • Park, Jong-Ho;Park, Sujin;Song, Kyuseok
    • Mass Spectrometry Letters
    • /
    • v.4 no.3
    • /
    • pp.51-54
    • /
    • 2013
  • Isotopic analysis using thermal ionization mass spectrometry coupled with scanning electron microscopy (SEM-TIMS) was performed to determine the isotopic ratios of uranium contained in micro-particles in the 6th Nuclear Signatures Interlaboratory Measurement Evaluation Programme (NUSIMEP-6) sample. Elemental analysis by energy dispersive X-ray spectroscopy (EDS) was conducted on uranium-bearing mirco-particles, which were transferred to rhenium filaments for TIMS loading using a micromanipulation system in a SEM. A multi-ion-counter system was utilized to detect the ion signals of the four isotopes of uranium simultaneously. The isotope ratios of uranium corrected by bracketing using a reference material showed excellent agreement with the certified values. The measurement accuracy for $n(^{234}U)/n(^{238}U)$ and (b) $n(^{235}U)/n(^{238}U)$ was 10% and 1%, respectively, which met the requirements for qalification for the NetWork of Analytical Laboratories (NWAL).

Ultrasonic evaluation of small surface fatigue cracks initiating in residual stress zone (잔류응력 영역에서 발생한 작은 피로균열의 초음파 평가)

  • Kang Kae-Myung;Kim Jin-Yeon
    • Journal of the Korean Institute of Gas
    • /
    • v.4 no.1 s.9
    • /
    • pp.55-62
    • /
    • 2000
  • A surface acoustic wave method for the evaluation of small fatigue crack initiated from a pit-type surface flaw is presented. In-situ ultrasonic experiments are performed for aluminum 2024-T3 alloy samples under the fatigue test. During the fatigue test, the surface acoustic wave reflection signal from the pit and crack is measured under different hold-stress levels. From the measured and predicted surface wave reflections the depths of fully and partially open cracks are determined and results are verified by comparing with SEM fractography The crack opening behavior of the fatigue crack is evaluated from the predicted effective crack depths. The method developed in this study can be applied to monitor and characterize crack initiation and propagation from pit-type surface flaws in the early stage of fatigue life.

  • PDF

Effects of POS System and Its Information Quality on POS Information Use and Marketing Performance (POS 시스템품질 및 정보의 질적 특성이 POS 정보활용과 마케팅성과에 미치는 영향 -슈퍼 체인을 중심으로-)

  • Kim Hyang-Ran;Lim Chae-Kwan
    • Management & Information Systems Review
    • /
    • v.7
    • /
    • pp.187-210
    • /
    • 2001
  • The purpose of this study is to develop an framework for the marketing performance evaluation of POS system by the theoretical model for evaluation of information system and the empirical data of Super-chains. This study were empirically examined an effect of POS system and its information quality on POS information use and another effect of POS information use on marketing performances of firms using POS system. Also, in order to achieve this purpose, a literature survey on MIS and marketing was conducted. In this study, the structural equation model(SEM) was established for verifying the relationship of above variables. And, several hypothesis were established and examined empirically from that SEM. In conclusion POS system and its information quality influenced positively on POS information use, and that information use influenced on marketing performance as the effectiveness of POS system operations.

  • PDF