• Title/Summary/Keyword: Scientific technique

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Facile Electrodeposition Technique for the Fabrication of MoP Cathode for Supercapacitor Application

  • Samanta, Prakas;Ghosh, Souvik;Murmu, Naresh Chandra;Lee, Joong Hee;Kuila, Tapas
    • Composites Research
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    • v.34 no.6
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    • pp.345-349
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    • 2021
  • The continued environmental pollution caused by fossil fuel consumption has prompted researchers around the world to develop environmentally friendly energy technologies. Electrochemical energy storage is the significant area of research in this development process, and the research significance of supercapacitors in this field is increasing. Herein, a simple electrodeposition synthetic route was explored to develop the MoP layered cathode material. The layered structure provided a highly ion-accessible surface for smooth and faster ion adsorption/desorption. After Fe was doped into MoP, the morphology of MoP changes and the electrochemical performance was significantly improved. Specific capacitance value of the binder-free FeMoP electrode was found to be 269 F g-1 at 2 A g-1 current density in 6 M aqueous KOH electrolyte. After adding Fe to MoP, an additional redox contribution was observed in the redox conversion from Fe3+ to Fe2+ redox pair, and the charge transfer kinetics of MoP was effectively improved. This research can provide guidance for the development of supercapacitor electrode materials through simple electrodeposition technology.

Development and Application of MEA(Model-Eliciting Activities) Program Applying the Invention Technique(TRIZ): Focus on Students' Conceptual Change (발명기법(TRIZ)을 적용한 MEA(Model-Eliciting Activities) 프로그램 개발 및 적용 -학생들의 개념 변화를 중심으로-)

  • Kang, Eunju
    • Journal of The Korean Association For Science Education
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    • v.42 no.1
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    • pp.161-176
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    • 2022
  • This study developed an MEA program to which the invention technique was applied and analyzed the conceptual change of students. The MEA activity applying the invention technique (TRIZ) was composed of the topic of making a paper electric circuit in the section 'Using electricity' presented in the 6th grade textbook. As a way to materialize ideas for problem solving, among the TRIZ techniques, division, integration, multi-purpose, overlapping, subtraction, and converse techniques were extracted and applied. The devised program consists of examining invention techniques (1st session), problem-solving (2nd and 3rd sessions), and expressing the problem-solving process (4th session). As a result of applying to 6th grade elementary school students, it was confirmed that the scientific concept of the experimental group participating in the MEA class to which the invention technique was applied was improved compared to the control group participating in the general class. As a result of calculating the scientific concept improvement index, the control group showed a low educational effect of 0.15, and the experimental group showed an intermediate educational effect of 0.69. This study is meaningful in that it suggests a specific way to graft invention education into science subjects.

Detection of flaw in steel anchor-concrete composite using high-frequency wave characteristics

  • Rao, Rajanikant;Sasmal, Saptarshi
    • Steel and Composite Structures
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    • v.31 no.4
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    • pp.341-359
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    • 2019
  • Non-monolithic concrete structural connections are commonly used both in new constructions and retrofitted structures where anchors are used for connections. Often, flaws are present in anchor system due to poor workmanship and deterioration; and methods available to check the quality of the composite system afterward are very limited. In case of presence of flaw, load transfer mechanism inside the anchor system is severely disturbed, and the load carrying capacity drops drastically. This raises the question of safety of the entire structural system. The present study proposes a wave propagation technique to assess the integrity of the anchor system. A chemical anchor (embedded in concrete) composite system comprising of three materials viz., steel (anchor), polymer (adhesive) and concrete (base) is considered for carrying out the wave propagation studies. Piezoelectric transducers (PZTs) affixed to the anchor head is used for actuation and the PZTs affixed to the surrounding concrete surface of the concrete-anchor system are used for sensing the propagated wave through the anchor interface to concrete. Experimentally validated finite element model is used to investigate three types of composite chemical anchor systems. Studies on the influence of geometry, material properties of the medium and their distribution, and the flaw types on the wave signals are carried out. Temporal energy of through time domain differentiation is found as a promising technique for identifying the flaws in the multi-layered composite system. The present study shows a unique procedure for monitoring of inaccessible but crucial locations of structures by using wave signals without baseline information.

Biopuncture, A Multitarget Therapy in the Treatment of Individuals with Knee Osteoarthritis: state of the art

  • Pedro Ivan Arias-Vazquez;Maria Antonieta Ramirez-Wakamatzu;Blanca Gabriela Legorreta-Ramirez
    • Journal of Pharmacopuncture
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    • v.27 no.3
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    • pp.190-198
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    • 2024
  • Background: Biopuncture is a described technique that consists in subcutaneous injection of antihomotoxic drugs (homeopathic compounds) mixed with other substances such as local anesthetics or dextrose; This has been proposed as a treatment option to reduce musculoskeletal pain in various locations, including knee osteoarthritis. Objectives: The objective of this manuscript was to carry out a comprehensive review of the published information on the use of Biopuncture in patients with knee osteoarthritis. Methods: A scientific search was performed using online databases following the terms (Biopuncture) and (Knee Osteoarthritis) to identify scientific manuscripts that were related to the use of Biopuncture in the treatment of individuals with knee osteoarthritis. Results: With the information found, a theoretical framework was integrated that describes the components of Biopuncture, its mechanism of action and practical topics for the application of the technique. Conclusion: Biopuncture appears to be a potential, simple and low-risk therapeutic strategy in the treatment of knee osteoarthritis, which is applied through periarticular subcutaneous injections, with multitarget mechanisms of action at various physiopathological levels such as the modulation of the inflammatory process, decreased peripheral sensitization, and stimulation of antidegenerative and trophic mechanisms. Perhaps it can be part of the integrative treatments for knee osteoarthritis.

A Study on the Landscape Analysis and Evaluation Method : A Phenomenological Approach (경관분석 및 평가방법에 관한 연구 - 현상학적 접근 -)

  • 임승빈
    • Journal of the Korean Institute of Landscape Architecture
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    • v.16 no.1
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    • pp.43-51
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    • 1988
  • Phenomenological approach suggests a new dimension in landscape evaluation, which is a contrast to the existing scientific evaluation methods. The characteristics of the phenomenological approach is qualitative, holistic, open, and experiential, whereas that of the scientific approach is quantitative, reductive, closed, and experimental. In phenomenological approach, the average response of a group is not considered as meaningful in landscape evaluation. Instead, the individual response, experience, and feeling are considered as important. In phenomenological approach, people try to see the real world as it is, while scientists tend to simplify the real world in order to handle the complex Phenomena easily. Due to its holistic and qualitative nature, the phenomenological approach has limitations to be a practical landscape evaluation technique. However, recent research demonstrate the possibility of practical phenomenological landscape evaluation technique which is able to satisfy the criteria scientific methods should meet.

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Automated Scoring of Scientific Argumentation Using Expert Morpheme Classification Approaches (전문가의 형태소 분류를 활용한 과학 논증 자동 채점)

  • Lee, Manhyoung;Ryu, Suna
    • Journal of The Korean Association For Science Education
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    • v.40 no.3
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    • pp.321-336
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    • 2020
  • We explore automated scoring models of scientific argumentation. We consider how a new analytical approach using a machine learning technique may enhance the understanding of spoken argumentation in the classroom. We sampled 2,605 utterances that occurred during a high school student's science class on molecular structure and classified the utterances into five argumentative elements. Next, we performed Text Preprocessing for the classified utterances. As machine learning techniques, we applied support vector machines, decision tree, random forest, and artificial neural network. For enhancing the identification of rebuttal elements, we used a heuristic feature-engineering method that applies experts' classification of morphemes of scientific argumentation.

Analysis of Automotive Paints using Pyrolysis-Gas Chromatography (열분해-가스크로마토그라피에 의한 자동차 페인트 분석)

  • Shon, Sung-Kun;Park, Ha-Sun;Lee, Jin-Sook;Hong, Sung-Wook;Park, Sung-Woo;Cho, Sung-Hye
    • Analytical Science and Technology
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    • v.13 no.1
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    • pp.101-107
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    • 2000
  • The automotive paints could be generally differentiated by color, layer sequence and chemistry of the paint layers comprising each of the topcoat and the primer system. The successful identification of hit-andrun a and traffic accidental vehicles from evidential paint fiagments is greatly facilitated with a comprehensive laboratory collection of reference paint samples and the technique for direct analysis without sample preparation. The Pyrolysis-Gas Chromatography(PGC) is a precise and reliable method for performing both quantitative and qualitative analysis of polymeric materials and forensic samples. Our Forensic Laboratory is conducting the examination and identification of 73 reference paint samples; 4 colors of each domestic automotive make that is popular in Korea, by Curie Point Pyrolyzer(JHP-3) and GC with capillary column(ultra alloy-5). This method can be used not only to compare paint traces with their suspected sources, but also to identify the type, make and model of the automotive car.

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A Study of Conservation treatment and Scientific Analysis for Gilt-bronze ornament Excavated from DeokCheon-Ri, Gyeong Ju (경주 덕천리 유적 출토 금동장식의 보존처리 및 과학적 분석 연구)

  • Seo, Jung-eun;Han, Min-su;Ham, Chul-hee
    • 보존과학연구
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    • s.27
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    • pp.23-42
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    • 2006
  • This study is about gilt bronze ornament, that is from Deok Cheon-Ri in Gyeong Ju, of conservation treatment process and of scientific analysis. This relic gathered with soil around the relic by Polyurethane foam. While the relic got rid of soil, Took X-rays. As the result, we decided to process reconstruction as condition that the relic was dug up. After the conservation treatment processed, we made a frame to display the relic. Investigated manufacture techniques of the relic after the conservation treatment processed, and thenexecuted scientific analysis of the relic for a chemical experiment. A analysis of the results of components for composition layers using the SEM-EDS can be briefly summarized as below; Firstly, the average contents of outer, inner and body corrosion layer have a Cu-60.9~39.3wt% and analyzed a little impurities material which is Fe-0.5wt%.Secondly, the average contents of body have a Cu-99.7wt% which was using manufactured by pure copper. Thirdly, gold layer have a mercury of 9.5wt% which indicate that layer was manufactured by mercury amalgam gilding technique.

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Sliding Wear of Alumina-silicon Carbide Nanocomposites

  • Kim, Seung-Ho;Lee, Soo-Wohn;Kim, Yun-Ho;Riu, Doh-Hyung;Tohru Sekino;Koichi Niihara
    • Journal of the Korean Ceramic Society
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    • v.38 no.12
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    • pp.1080-1084
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    • 2001
  • Alumina-based nanocomposites have improved mechanical properties such as hardness, fracture toughness and fracture strength compared to monolithic ceramics. In this study, alumina with 5 vol% of nanosized SiC was sintered by a hot pressing technique at 1600$\^{C}$, 30 MPa for 1h in an argon gas atmosphere. Microstructures and mechanical properties in alumina-SiC nanocomposite were investigated. Moreover, tribological properties in air and water were compared each other. Relationships of wear properties with mechanical properties such as hardness, strength, and fracture toughness as well as microstructure were studied. Based on experimental results it was found that nanosized SiC retarded grain growth of matrix alumina. Mechanical properties such as hardness, fracture toughness and strength were improved by the addition of nanosized SiC in alumina. Improved mechanical properties resulted in increased sliding wear resistance. Tribological behavior of nanocomposites in water seemed to be governed by abrasive wear.

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