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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

Standardization of Buckypaper Composite Actuator Fabrication Process and Improvement of Force Generation

Unknown Date (has links)
The Buckypaper/Nafion composite actuator (BCA) is promising for lightweight and micro-robotic system applications. Lightweight BCA provides an energy-efficient and flexible design to achieve muscle-like actuation for micro-actuator applications. The BCA encompasses of a solid Nafion electrolyte stacked between two conductive carbon nanotube thin thins or Buckypaper (BP) sheets. As an ionic electro-active polymer (iEAP), Nafion's response to an electrical signal is similar to the electrochemical response of biological muscles. The adhesion between the electrolyte film and the electrode materials is critical to the actuator performance. BCA manufacturing avoids the complexities of repetitive metallic plating, as BP supplies a high surface area film of conductive carbon nanotubes. Since the actuator's charging occurs where the constituent materials come in contact, a standard manufacturing process needs to be developed to ensure repeatability. This research includes two focuses. The first focus pertains to optimizing the ion-exchange processes that improve Nafion's ionic transport properties. The second focus is to strengthening the interaction between Nafion and Buckypaper, which will ensure effective charge accumulation at the interface and improve the BCA's mechanical properties relevant to force exertion. The research presents a novel BCA manufacturing approach to achieve excellent repeatability and significantly improves the BCA's mechanical properties / A Thesis submitted to the Department of Industrial and Manufacturing Engineering in partial fulfillment of the requirements for the degree of Master of Science. / Spring Semester, 2014. / April 18, 2014. / Includes bibliographical references. / Zhiyong Liang, Professor Directing Thesis; Arda Vanli, Committee Member; Chad Zeng, Committee Member.
52

A Study of Nanostructure and Properties of Mixed Nanotube Buckypaper Materials: Fabrication, Process Modeling Characterization, and Property Modeling

Unknown Date (has links)
Single-walled carbon nanotube buckypaper (SBP) is a thin film of preformed nanotube networks that possesses many excellent properties. SBP is considered to be very promising in the development of high-performance composite materials; however, the high cost of single-walled nanotubes (SWNTs) limits industrial applications of SBP materials. Mixed buckypaper (MBP) is a more affordable alternative that combines SWNTs with low-cost multi-walled nanotubes (MWNTs) or carbon nanofibers (CNFs) to retain most of the excellent properties of SBP while significantly reducing the cost. This study proposes a manufacturing process of MBPs. The process parameters were studied through experimental design and statistical analysis. The parameters included mixing material type, mixing ratio, sonication effect, surfactant amount, and cleaning effect. The effects of the parameters on nanostructure uniformity, purity, Brunauer-Emmett-Teller (BET) surface area and electrical conductivity of the resultant MBPs were revealed. Results of the study show that all those parameters and their interactions are influential to the dispersion and uniformity of nanostructure and purity, but only mixing material type and ratio are influential to the BET surface area and electrical conductivity. To systematically reveal the process-nanostructure-property relationship of SBP and MBP materials, the nanostructures of the buckypapers were characterized as rope size, length and pore size distributions of the nanomaterials in resultant buckypapers. These distributions featured bimodal phenomenon due to different material mixtures; therefore, the distributions were further separated into two individual ones and fitted into Weibull distributions. Two nanostructure-property models of buckypaper materials were developed. The specific surface area model was built upon the characterization and analysis of buckypaper nanostructures. The model showed that rope size distribution and mixed ratio of nanomaterials are governing factors for the resultant specific surface area of buckypaper. The electrical conductivity model captured multiscale electrical transport phenomenon of nanotube networks in buckypapers. The model considered chirality, contact area, contact type, diameter, length and orientation distributions of nanotubes in buckypapers. The proposed models not only can predict property trends correctly, but can also reveal the critical process-nanostructure-property relationships of buckypaper materials. The results are important for the further tailoring and optimization of the manufacturing process and properties of nanotube buckypapers. / A Dissertation submitted to the Department of Industrial and Manufacturing Engineering in partial fulfillment of the requirements for the degree of Doctor of Philosophy. / Degree Awarded: Fall Semester, 2007. / Date of Defense: November 14, 2007. / Carbon Nanotubes, Buckypaper Statistical Analysis, Uniformity, Surface Area, Electrical Conductivity / Includes bibliographical references. / Zhiyong Liang, Professor Directing Dissertation; Jim P. Zheng, Outside Committee Member; Ben Wang, Committee Member; Chuck Zhang, Committee Member; David Jack, Committee Member.
53

A distribution system simulation for companies with production to order or engineering to order characteristics

Lueken, Markus 08 1900 (has links)
No description available.
54

A quantification of the economic value of flexibility

Laengle, Karl 05 1900 (has links)
No description available.
55

The development of systematic controllability assessment for process control designs /

Ekawati, Estiyanti. January 2003 (has links)
Thesis (Ph.D.) --Murdoch University, 2003. / Thesis submitted to the Division of Science and Engineering. Includes bibliographical references.
56

Optimizing usage of recycled material in a remanufacturing environment

Shah, Purvin. January 2005 (has links) (PDF)
Thesis (M.Sc.)--State University of New York at Buffalo, 2005. / Includes bibliographical references.
57

The evaluation of a production scheduling heuristic for production lines with changeover costs and dependent parallel processors

Dai, Bin. January 1990 (has links)
Thesis (M.S.)--Ohio University, November, 1990. / Title from PDF t.p.
58

Analytical approach to feature based process analysis and design

Lee, Jae-Woo. January 1996 (has links)
Thesis (M.S.)--Ohio University, August, 1996. / Title from PDF t.p.
59

Optimization of a face milling cutter using response surface methods

Doolan, Patrick, January 1970 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1970. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
60

Factors affecting industrial learning on interrupted production schedules

Daniels, Roger Warren. January 1966 (has links)
LD2668 .T4 1966 D35 / Master of Science

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