Three-dimensional femtosecond laser processing for lab-on-a-chip applications

AbstractThe extremely high peak intensity associated with ultrashort pulse width of femtosecond laser allows us to induce nonlinear interaction such as multiphoton absorption and tunneling ionization with materials that are transparent to the laser wavelength. More importantly, focusing the femtosecond laser beam inside the transparent materials confines the nonlinear interaction only within the focal volume, enabling three-dimensional (3D) micro- and nanofabrication. This 3D capability offers three different schemes, which involve undeformative, subtractive, and additive processing. The undeformative processing preforms internal refractive index modification to construct optical microcomponents including optical waveguides. Subtractive processing can realize the direct fabrication of 3D microfluidics, micromechanics, microelectronics, and photonic microcomponents in glass. Additive processing represented by two-photon polymerization enables the fabrication of 3D polymer micro- and nanostructures for photonic and microfluidic devices. These different schemes can be integrated to realize more functional microdevices including lab-on-a-chip devices, which are miniaturized laboratories that can perform reaction, detection, analysis, separation, and synthesis of biochemical materials with high efficiency, high speed, high sensitivity, low reagent consumption, and low waste production. This review paper describes the principles and applications of femtosecond laser 3D micro- and nanofabrication for lab-on-a-chip applications. A hybrid technique that promises to enhance functionality of lab-on-a-chip devices is also introduced

Enabling Non-Professional Users To Bring Physical Processes Into The Industrial Metaverse

Augmented reality is essential for the Metaverse because, with this technology, people, spaces, and things can be digitally and physically intertwined. But the creation of AR content is a very complex process carried out by technically skilled developers. For the Metaverse, it is necessary to enable non-professional users to create AR content. We, therefore, want to study the challenges that non-professional users face while creating AR content for process guidance systems that represents a physical process. For this reason, we conducted an exploratory analysis using ten AR authoring experts and arranged a focus group with domain experts and AR authoring experts. As a result, we identified four fundamental design requirements on how an AR authoring tool must be designed to bring physical processes into the Metaverse. Thus, we contribute to understanding AR-based process guidance systems and enable the instantiation and evaluation of an AR authoring tool in large DSR project

Degradation modeling and degradation-aware control of power electronic systems

The power electronics market is valued at $23.25 billion in 2019 and is projected to reach$ 36.64 billion by 2027. Power electronic systems (PES) have been extensively used in a wide range of critical applications, including automotive, renewable energy, industrial variable-frequency drive, etc. Thus, the PESs\u27 reliability and robustness are immensely important for the smooth operation of mission-critical applications. Power semiconductor switches are one of the most vulnerable components in the PES. The vulnerability of these switches impacts the reliability and robustness of the PES. Thus, switch-health monitoring and prognosis are critical for avoiding unexpected shutdowns and preventing catastrophic failures. The importance of the prognosis study increases dramatically with the growing popularity of the next-generation power semiconductor switches, wide bandgap switches. These switches show immense promise in the high-power high-frequency operations due to their higher breakdown voltage and lower switch loss. But their wide adaptation is limited by the inadequate reliability study. A thorough prognosis study comprising switch degradation modeling, remaining useful life (RUL) estimation, and degradation-aware controller development, is important to enhance the PESs\u27 robustness, especially with wide bandgap switches. In this dissertation, three studies are conducted to achieve these objectives- 1) Insulated Gate Bipolar Transistor (IGBT) degradation modeling and RUL estimation, 2) cascode Gallium Nitride (GaN) Field-Effect Transistor (FET) degradation modeling and RUL estimation, and 3) Degradation-aware controller design for a PES, solid-state transformer (SST). The first two studies have addressed the significant variation in RUL estimation and proposed degradation identification methods for IGBT and cascode GaN FET. In the third study, a system-level integration of the switch degradation model is implemented in the SST. The insight into the switch\u27s degradation pattern from the first two studies is integrated into developing a degradation-aware controller for the SST. State-of-the-art controllers do not consider the switch degradation that results in premature system failure. The proposed low-complexity degradation-aware and adaptive SST controller ensures optimal degradation-aware power transfer and robust operation over the lifetime

Tailoring the properties of PECVD deposited terpinen-4ol thin films

Polymer thin films have been of significant research interest in the field of, mechanics, optics, electronics and medicine. Bioactive coatings are extensively used in marine and medical field for the prevention of biofouling which is colonization of any wetted surface by flora and fauna. Fouling of the surfaces has severe implications for the performance of the material and biocide based coating have been used in the prevention of marine fouling. However, these coatings have adverse environmental effects. Natural antifouling products derived from organisms have been found to be an excellent alternative to biocide based strategies. Terpinen-4-ol derived from Australian Tea tree oil has antimicrobial properties. The Plasma enhanced chemical vapor deposition (PECVD) method has been used to develop environmentally friendly antifouling coating from Terpinen-4-ol. The effect of Process variables such as substrate temperature have been investigated on the PECVD of terpinen-4-ol. The influence of surface functionalization and the deposition mode of terpinen-4-ol plasma polymer on its antibacterial property has been studied. Coating created in the form of bilayer are tested for their marine antifouling behavior. The substrate temperature was found to influence the deposition mechanism of Terpinen-4-ol plasma polymers. Hydro Stable terpinen-4-ol plasma polymers were found to be formed at higher substrate temperature. Pulse plasma deposited films exhibited enhanced antibacterial performance. Grafting of ZnO nanoparticles onto the surface of the terpinen-4-ol polymer boosted the antibacterial and UV absorbing properties. The deposited bilayer coatings were effective in preventing the primary stage of marine biofouling. The bilayer acted as biocidal self-polishing coating

NASA SBIR abstracts of 1990 phase 1 projects

The research objectives of the 280 projects placed under contract in the National Aeronautics and Space Administration (NASA) 1990 Small Business Innovation Research (SBIR) Phase 1 program are described. The basic document consists of edited, non-proprietary abstracts of the winning proposals submitted by small businesses in response to NASA's 1990 SBIR Phase 1 Program Solicitation. The abstracts are presented under the 15 technical topics within which Phase 1 proposals were solicited. Each project was assigned a sequential identifying number from 001 to 280, in order of its appearance in the body of the report. The document also includes Appendixes to provide additional information about the SBIR program and permit cross-reference in the 1990 Phase 1 projects by company name, location by state, principal investigator, NASA field center responsible for management of each project, and NASA contract number

Feasibility of remotely manipulated welding in space. A step in the development of novel joining technologies

In order to establish permanent human presence in space technologies of constructing and repairing space stations and other space structures must be developed. Most construction jobs are performed on earth and the fabricated modules will then be delivered to space by the Space Shuttle. Only limited final assembly jobs, which are primarily mechanical fastening, will be performed on site in space. Such fabrication plans, however, limit the designs of these structures, because each module must fit inside the transport vehicle and must withstand launching stresses which are considerably high. Large-scale utilization of space necessitates more extensive construction work on site. Furthermore, continuous operations of space stations and other structures require maintenance and repairs of structural components as well as of tools and equipment on these space structures. Metal joining technologies, and especially high-quality welding, in space need developing

Feasibility study of an Integrated Program for Aerospace-vehicle Design (IPAD) system. Volume 6: Implementation schedule, development costs, operational costs, benefit assessment, impact on company organization, spin-off assessment, phase 1, tasks 3 to 8

A baseline implementation plan, including alternative implementation approaches for critical software elements and variants to the plan, was developed. The basic philosophy was aimed at: (1) a progressive release of capability for three major computing systems, (2) an end product that was a working tool, (3) giving participation to industry, government agencies, and universities, and (4) emphasizing the development of critical elements of the IPAD framework software. The results of these tasks indicate an IPAD first release capability 45 months after go-ahead, a five year total implementation schedule, and a total developmental cost of 2027 man-months and 1074 computer hours. Several areas of operational cost increases were identified mainly due to the impact of additional equipment needed and additional computer overhead. The benefits of an IPAD system were related mainly to potential savings in engineering man-hours, reduction of design-cycle calendar time, and indirect upgrading of product quality and performance

Fabrication of nanostructured free-standing Fresnel zone plate for neutral matter-waves microscopy

Masteroppgave i fysikkPHYS399MAMN-PHY

Space benefits: The secondary application of aerospace technology in other sectors of the economy

Benefit cases of aerospace technology utilization are presented for manufacturing, transportation, utilities, and health. General, organization, geographic, and field center indexes are included